Step-like dependence of memory function on pulse width in spintronics reservoir computing.

Physical reservoir computing is a type of recurrent neural network that applies the dynamical response from physical systems to information processing. However, the relation between computation performance and physical parameters/phenomena still remains unclear. This study reports our progress regarding the role of current-dependent magnetic damping in the computational performance of reservoir computing. The current-dependent relaxation dynamics of a magnetic vortex core results in an asymmetric memory function with respect to binary inputs. A fast relaxation caused by a large input leads to a fast fading of the input memory, whereas a slow relaxation by a small input enables the reservoir to keep the input memory for a relatively long time. As a result, a step-like dependence is found for the short-term memory and parity-check capacities on the pulse width of input data, where the capacities remain at 1.5 for a certain range of the pulse width, and drop to 1.0 for a long pulse-width limit. Both analytical and numerical analyses clarify that the step-like behavior can be attributed to the current-dependent relaxation time of the vortex core to a limit-cycle state.

Five-day regimen of azacitidine for lower-risk myelodysplastic syndromes (refractory anemia or refractory anemia with ringed sideroblasts): A prospective single-arm phase 2 trial.

Although azacitidine is the first-line drug for higher-risk myelodysplastic syndrome (MDS) patients, its efficacy for lower-risk MDS remains unestablished. Therefore, we conducted a prospective study to examine the efficacy and safety of a 5-day regimen of azacitidine (AZA-5) for lower-risk MDS. The primary endpoint was hematological improvement (HI) after 4 courses of therapy. A total of 51 patients with lower-risk MDS based on the French-American-British (FAB) classification (44 patients with refractory anemia [RA] and 7 patients with refractory anemia with ringed sideroblasts [RARS]) were enrolled from 6 centers in Japan. The median age was 75 years (range: 51-88). These patients received AZA-5 (75 mg/m2 ; once daily for 5 sequential days). The median number of AZA-5 courses was 8 (range: 1-57), and 45 patients (88.2%) received more than 4 courses. HI and transfusion independency were seen in 24 patients (47.1%) and 11 patients (39.2%), respectively. A total of 11 patients (21.6%) achieved complete remission or marrow remission. WT1 mRNA levels were not significantly correlated with therapy response. Grade 3 or 4 neutropenia and thrombocytopenia occurred in 26 (51.0%) and 11 (21.5%) patients, respectively. Nonhematological grade 3 or 4 adverse events were observed in 9 patients (17.6%). Together, these results indicate that AZA-5 is feasible and effective for lower-risk MDS patients as well as for higher-risk MDS patients.

A case of secondary leukemia subsequent to myelodysplastic syndromes successfully treated with azacitidine.

Elderly patients with secondary acute myeloid leukemia (AML) following myelodysplastic syndrome (MDS) are often medically unfit for or resistant to chemotherapy, and their prognosis is dismal. In the present paper, we reported a case of secondary leukemia following MDS in an 80-year-old male patient who was deemed unfit for chemotherapy owing to his old age and poor physical condition. Despite a high tumor burden, treatment with AZA exerted a remarkable response, leading to an immediate cytoreduction in our case. Our results suggest that AZA can be an attractive therapeutic option for elderly MDS or AML patients, offering adequate efficacy and high tolerability.

Clinical importance of human herpes virus-8 and human immunodeficiency virus infection in primary effusion lymphoma.

Primary effusion lymphoma (PEL) is a rare type of non-Hodgkin lymphoma that usually develops in immunosuppressed patients infected with human herpes virus-8 (HHV-8) in conjunction with human immunodeficiency virus (HIV) infection. However, there are several reports of HHV-8-related HIV-negative cases and HHV-8-unrelated HIV-negative cases, mainly in immunodeficient and elderly patients. Here, we report one case of HHV-8-related HIV-negative PEL with gastric cancer (case 1) and one case of HHV-8-unrelated HIV-negative effusion-based lymphoma (case 2), both in elderly men. A 73-year-old man and a 79-year-old man were admitted because of lymphomatous effusions, and no mass was detectable in both cases. They were diagnosed as having malignant effusion lymphoma on the basis of cytological findings indicating atypical lymphoid cells and the expression of CD20 and CD79a. To detect evidence of HHV-8 infection in neoplastic cells, immunocytochemical staining for ORF73/ latent nuclear antigen-1 (LNA-1) was performed. The results revealed that case 1 was ORF73-positive, and case 2 was ORF73-negative. Rituximab-based chemotherapy (R-THPCOP: rituximab, pirarubicin, cyclophosphamide, vincristine, prednisolone) was administered to both patients and complete remission was achieved in both. Compared to most HIV-positive PEL cases, these two cases showed a good response to chemotherapy. In cases of PEL, we should focus on HHV-8 infection and HIV status for determining prognosis.

Interleukin-8 in the pathogenesis of primary central nervous system lymphoma in association with HIV infection.

The pathogenesis of acquired immunodeficiency syndrome-associated primary central nervous system lymphoma (AIDS-associated PCNSL) remains unclear. However, cell adhesion molecules have been reported to be strongly associated with PCNSL. In this study, we established Epstein-Barr virus (EBV)-transformed lymphoblastoid cell lines (LCLs) from HIV-positive patients (LCL(HIV)) and normal individuals (LCL(N)). The expression of CD18 antigen by LCL(HIV) was stronger than that by LCL(N). We performed a cell adhesion assay using ISO-HAS, which is the human hemangiosarcoma cell line and expresses intercellular adhesion molecule 1 (CD54). The binding rates of LCL(HIV) and ISO-HAS without stimulation were higher than those of LCL(N). Further, we demonstrated that azidothymidine or simvastatin inhibited the binding rates of LCL(HIV) and ISO-HAS more significantly than those of LCL(N). Further, the levels of interleukin (IL)-8, a CD18 inducer, were higher in LCL(HIV) than in LCL(N). We conclude that interaction between IL-8 and CD18 may be critical to AIDS-related PCNSL.

A case of chronic myelomonocytic leukemia who developed pericardial effusion during stably controlled leukocytosis.

We report a rare case of chronic myelomonocytic leukemia (CMML) with pericardial effusion. After receving the diagnosis of CMML, she had been successfully treated with hydroxycarbamide (HU). However, she was admitted to our hospital due to pericardial effusion. The majority of the cells in the pericardial fluid were monocytes. We made the diagnosis of pericardial involvement with CMML cells and intravenously administered etoposide (100 mg/body daily for 5 days). Although CMML cells disappeared from the peripheral blood, the pericardial effusion still persisted. This case indicates that pericardial effusion is a possible and life-threatening complication in CMML patients despite stably controlled leukocytes.

Efficacy of rituximab monotherapy for an elderly hemodialysis patient with primary cardiac lymphoma.

We report a case of primary cardiac lymphoma (PCL) occurring in a 76-year-old man during maintenance hemodialysis. Chest computed tomography (CT) revealed a tumor with pericardial effusion in the left ventricular posterior wall. Cytological examination of the pericardial fluid revealed monotonous lymphoid cells positive for B-cell markers, and clonal immunoglobulin heavy chain gene rearrangement was detected, indicating B-cell lymphoma. Rituximab monotherapy was administered biweekly at the therapeutic level on hemodialysis. The follow-up chest CT showed tumor disappearance with pericardial fluid after two courses of therapy. Rituximab monotherapy was effective for an elderly hemodialysis patient with PCL.

Relationship between expression of mutant type glutathione S-transferase theta-1 gene and reactivity of rapamycin in myelodysplastic syndrome.

We previously reported mRNA expression of glutathione S-transferases theta (GSTT)-1, wild type (623 bp) and mutant (500 bp), in patients with myelodysplastic syndrome (MDS). The deletion of 123 bp creates a sequence that is homologous to the mammalian target of rapamycin (mTOR). To analyze the function of mutant GSTT-1 gene, stable transformants for the mutant and wild-type GSTT-1 gene, respectively, were established. In this study, the expression of the wild and mutant type of the GSTT-1 gene of those stable transformants in cell lines and in bone marrow cells from MDS patients by reverse-transcription polymerase chain reaction (RT-PCR) was observed in the presence or absence of rapamycin. Significant growth inhibition by rapamycin was observed among stable transformants for the mutant GSTT-1 gene, but not wild type GSTT-1 gene, and was indicative of typical apoptosis.

Influence of Epstein-Barr virus infection in adult T-cell leukemia.

The involvement of adult T-cell leukemia (ATL) cells in organs such as the skin and lymph nodes is observed in about 50% of cases of ATL. Epstein-Barr virus (EBV) infection has often been observed in the clinical course of ATL. In this study, we established two B-cell lines from peripheral blood of patients with ATL. EBV DNA, proviral DNA for HTLV-1 and Tax mRNA were detected in both lines. As part of the characterization of these cells, an enhanced expression of intercellular adhesion molecule-1 (ICAM-1) (CD54) or ICAM-3 (ICAM-3) (CD50), lymphocyte function-1 (LFA-1) (CD11a/CD18), and Mac-1 (CD11b/CD18) was observed. To investigate the role of the interaction of these viruses, we transfected EBV and/or HTLV-1 into a healthy donor's lymphocytes, an EBV-infected B cell line, Raji, and a HTLV-1 negative T-cell line, Jurkat. Enhanced expression of adhesion molecules was also observed in double transfectants (EBV and HTLV-1). In the clinical course of ATL, LMP-1, EBNA-2, CD50 and CD54 were detected in lymph nodes and skin specimens by immunohistochemical staining. Furthermore, high levels of interleukin-4 (IL-4) were detected in these cell lines and transfectants. The results indicated that coinfection with HTLV-1 and EBV may induce aggressive organ involvement through the enhanced expression of adhesion molecules via IL-4 signaling. A new mechanism of ATL involvement is discussed.

Clinical efficacy of all-trans retinoic acid for treating adult T cell leukemia.

PURPOSE: We previously reported that all-trans retinoic acid (ATRA) inhibited growth in human T-cell leukemia virus type I (HTLV-I)-positive T-cell lines and in fresh cells from patients with adult T cell leukemia (ATL). Here, we confirmed the clinical effects of ATRA in 20 patients with ATL. MATERIALS AND METHODS: The 20 patients (n = 20) with a median age of 56 (range 35-73) years who were diagnosed with ATL received ATRA orally. RESULTS: The efficacy of treatment was as follows: no complete response (CR), a partial response (PR) in 40% of the patients, no change (NC) in 45% of the patients, and a progressive disease (PD) in 15% of the patients. In seven acute-type ATL patients, a PR was achieved in two (28.5%), NC was observed in two (28.5%), and a PD was observed in three (42.8%). In three lymphoma-type ATL patients, a PR (100%) was achieved. Among four chronic-type ATL patients, a PR was achieved in one (25%) and NC was observed in the remaining three (75%). In six smoldering-type ATL patients, a PR was achieved in two (33.3%) and NC was observed in four (66.6%). The major side effects were headache (n = 5), transient liver dysfunction (n = 2), hyperlipidemia (n = 2), and anorexia (n = 1). CONCLUSION: These results indicated that ATRA might be a useful agent for the safe treatment of ATL.

Partial restoration of immunoglobulin production by cytokines in common variable immunodeficiency.

We describe a 26-year-old female referred to us because of recurrent bacterial pneumonia. Her immunoglobulin profile on admission was; IgG 1920 mg/l, IgA 60 mg/l, IgM 260 mg/l, IgD below 20 mg/l, IgE below 1 kU/l. Antinuclear antibodies, EBV VCA IgM, anti-parvovirus B19 IgM antibodies and hepatitis infection markers were all negative. Bone marrow aspiration revealed normal cellularity without abnormal cells, especially plasma cell proliferation. No rearrangement for IgH and TCR was observed as determined by Southern blot analysis. By the given data, a diagnosis of common variable immunodeficiency (CVID) was made. The genesis of this disease remained unclear. In this study, proliferation and immunoglobulin production with or without several stimulators were examined. Proliferation stimulated by PHA, Con-A, LPS, or IL-2 was decreased compared to that of healthy individuals. Immunoglobulin production after stimulation with several agents was quite low. Interestingly, however, IL-2 or IL-4 could increase IgM production on 6 days culture significantly. These results indicate that IL-2 or IL-4 possibly restore T cell responses to several antigens and induce B cell differentiation.

All-trans retinoic acid attacks reverse transcriptase resulting in inhibition of HIV-1 replication.

We previously reported that all-trans retinoic acid (ATRA) inhibited growth in HTLV-1-positive T-cell lines and fresh cells from patients with adult T-cell leukemia. Interestingly, ATRA significantly inhibited reverse transcriptase (RT) activity similar to azidothimidine (AZT) in HTLV-1-positive T-cell lines. To clarify whether ATRA has an inhibitory effect on the replication of HIV, we examined HIV proviral DNA in a HIV-1-positive cell line (8E5) using real time PCR. ATRA as well as AZT reduced the proviral DNA load of 8E5 in a dose-dependent manner. These results suggest that there is a common element of ATRA signaling in both HTLV-1 and HIV. Furthermore, we examined the effects of ATRA on viral replication in primary lymphocytes of three individuals infected with HIV. ATRA reduced viral replication significantly similar to AZT. These findings suggested that ATRA acts as a RT inhibitor, reducing the HIV-1 proviral DNA load. Finally, we conclude that ATRA may be a potential therapeutic agent for HIV infection.