Cytomegalovirus-associated hemophagocytic syndrome with clonal cytogenetic abnormalities in an elderly male.
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Aged↗
Biomedical subjects
Yasuo Ikeda
Publications and source records attributed to Yasuo Ikeda.
Reactive oxygen species act through p38 MAPK to limit the lifespan of hematopoietic stem cells.
Hematopoietic stem cells (HSCs) undergo self-renewing cell divisions and maintain blood production for their lifetime. Appropriate control of HSC self-renewal is crucial for the maintenance of hematopoietic homeostasis. Here we show that activation of p38 MAPK in response to increasing levels of reactive oxygen species (ROS) limits the lifespan of HSCs in vivo. In Atm(-/-) mice, elevation of ROS levels induces HSC-specific phosphorylation of p38 MAPK accompanied by a defect in the maintenance of HSC quiescence. Inhibition of p38 MAPK rescued ROS-induced defects in HSC repopulating capacity and in the maintenance of HSC quiescence, indicating that the ROS-p38 MAPK pathway contributes to exhaustion of the stem cell population. Furthermore, prolonged treatment with an antioxidant or an inhibitor of p38 MAPK extended the lifespan of HSCs from wild-type mice in serial transplantation experiments. These data show that inactivation of p38 MAPK protects HSCs against loss of self-renewal capacity. Our characterization of molecular mechanisms that limit HSC lifespan may lead to beneficial therapies for human disease.
Animals↗
Fludarabine-associated autoimmune hemolytic anemia occurring in B-cell chronic lymphocytic leukemia.
Autoimmune phenomena are reported to occur frequently in B-cell chronic leukemia (B-CLL). Fludarabine, one of the most effective chemotherapeutic agents for CLL, may increase the risk of these phenomena and may be life-threatening. Here we present a case of an 80-year-old man with B-CLL who developed autoimmune hemolytic anemia (AIHA), associated with one cycle of fludarabine treatment, and who was successfully treated with rituximab and prednisolone.
Aged, 80 and over↗
N-terminal region of CCAAT/enhancer-binding protein epsilon is critical for cell cycle arrest, apoptosis, and functional maturation during myeloid differentiation.
CCAAT/enhancer-binding protein epsilon (C/EBPepsilon) plays a critical role in terminal myeloid differentiation. Differentiation is an integrated process of cell cycle arrest, morphological change, functional maturation, and apoptosis. However, the molecular networks underlying these events in C/EBPepsilon-induced differentiation remain poorly understood. To reveal these mechanisms, we performed a detailed molecular analysis of C/EBPepsilon-induced differentiation using an inducible form of C/EBPepsilon. The activation of C/EBPepsilon induced growth arrest, morphological differentiation, the expression of CD11b and secondary granule proteins, and apoptosis in myeloid cell lines. Unlike C/EBPalpha, C/EBPepsilon dramatically up-regulated p27 with a concomitant down-regulation of cdk4/6 and cyclin D2/A/E. Moreover, the anti-apoptotic proteins Bcl-2 and Bcl-x were down-regulated, whereas pro-apoptotic protein Bax remained unchanged. Using a variety of mutants, we revealed that these events were all regulated by the N-terminal activation domain of C/EBPepsilon. Interestingly, some of the differentiation processes such as the induction of secondary granule protein genes were clearly inhibited by c-Myc; however, inhibition of apoptosis by Bcl-x did not affect the entire differentiation processes. These data indicate the N terminus of C/EBPepsilon to be solely responsible for most aspects of myeloid differentiation, and these events were differentially affected by c-Myc.
Animals↗
A novel nonpeptidyl human c-Mpl activator stimulates human megakaryopoiesis and thrombopoiesis.
NIP-004 is a novel synthetic compound developed to display human thrombopoietin (TPO) receptor (c-Mpl) agonist activity. NIP-004 displays species specificity, stimulating proliferation or differentiation of human c-Mpl-expressing cells such as UT-7/TPO and human CD34(+) cells but not murine c-Mpl-expressing cells or cynomolgus monkey cells. To test the mechanism of its action, we constructed mutant forms of c-Mpl; murine c-Mpl(L490H) dis-played a response to NIP-004, whereas human c-Mpl(H499L) lost this response, indicating that histidine in the transmembrane domain of c-Mpl is essential for its activity. Because histidine is not present in the c-Mpl transmembrane domain of rats, hamsters, rhesus macaques, and cynomolgus monkeys, we examined the in vivo efficacy of NIP-004 using mice that received xenotransplants. In immunodeficient nonobese diabetic (NOD)/Shi-scid, IL-2Rgamma(null) (NOG) mice receiving transplants of umbilical cord blood-derived CD34(+) cells, NIP-004 increased human megakaryoblasts, mature megakaryocytes, and circulating human platelets 6-fold, the latter being morphologically and functionally indistinguishable from normal human platelets. These observations indicate that NIP-004 is a novel human c-Mpl activator and induces human thrombopoiesis.
Animals↗
Protein S-K196E mutation as a genetic risk factor for deep vein thrombosis in Japanese patients.
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Adult↗
Brief oral cryotherapy for the prevention of high-dose melphalan-induced stomatitis in allogeneic hematopoietic stem cell transplant recipients.
We previously reported the efficacy of oral cryotherapy for the prevention of high-dose melphalan-induced stomatitis. The purpose of this study was to evaluate whether the further shortening of the duration of oral cryotherapy could minimize its side effects while sparing its efficacy. Seventeen consecutive recipients of allogeneic hematopoieic stem cell transplant conditioned with high-dose melphalan in combination with fludarabine alone or with fludarabine and additional radiation were enrolled in the study. The severity of stomatitis was graded according to the National Cancer Institute-Common Toxicity Criteria. Patients were kept on oral cryotherapy shortly before, during, and for additional 30 min after the completion of melphalan administration (60-min oral cryotherapy). Patients who were also enrolled in our previous study received the same type of oral cryotherapy but for additional 90 min after the completion of melphalan administration (120-min oral cryotherapy), and they served as controls. Only 2 (11.8%) of 17 patients receiving 60-min oral cryotherapy and 2 (11.1%) of 18 patients receiving 120-min oral cryotherapy developed grade 2 or 3 stomatitis, respectively. The difference between groups was not statistically significant (P = 0.677). The incidence of unpleasant symptoms such as chills and nausea during oral cryotherapy decreased significantly with 60-min oral cryotherapy, as compared with that associated with 120-min oral cryotherapy (P < 0.01). These results suggest that 60-min oral cryotherapy is as effective as 120-min oral cryotherapy at preventing high-dose melphalan-induced stomatitis, and shorter treatment might have contributed to relieve patient discomfort during oral cryotherapy.
Administration, Oral↗
Resveratrol induces apoptosis of human malignant B cells by activation of caspase-3 and p38 MAP kinase pathways.
Red wine polyphenol, trans-resveratrol (trans-3,4',5-trihydroxy stilbene), has potent chemopreventive effects against various tumors. In this study, we found for the first time that resveratrol rapidly induces S phase cell cycle arrest of human malignant B cells including myeloma cells in dose- and time-dependent manners, followed by S phase cell cycle arrest through ATM/Chk pathway. Resveratrol-induced apoptosis occurs in association with the activation of caspase-3 and the loss of mitochondrial transmembrane potentials. In addition, resveratrol induces the phosphorylation of p38 MAP kinase, and specific inhibition of p38 MAP kinase abolishes the resveratrol-induced apoptosis, indicating that activation of the p38 MAP kinase pathway is required for inducing apoptosis in malignant B cells. These results suggest that resveratrol may have potential as a novel therapeutic agent for the patients with B cell malignancies including multiple myeloma.
Antineoplastic Agents, Phytogenic↗
International prevalence, recognition, and treatment of cardiovascular risk factors in outpatients with atherothrombosis.
CONTEXT: Atherothrombosis is the leading cause of cardiovascular morbidity and mortality around the globe. To date, no single international database has characterized the atherosclerosis risk factor profile or treatment intensity of individuals with atherothrombosis. OBJECTIVE: To determine whether atherosclerosis risk factor prevalence and treatment would demonstrate comparable patterns in many countries around the world. DESIGN, SETTING, AND PARTICIPANTS: The Reduction of Atherothrombosis for Continued Health (REACH) Registry collected data on atherosclerosis risk factors and treatment. A total of 67,888 patients aged 45 years or older from 5473 physician practices in 44 countries had either established arterial disease (coronary artery disease [CAD], n = 40,258; cerebrovascular disease, n = 18,843; peripheral arterial disease, n = 8273) or 3 or more risk factors for atherothrombosis (n = 12,389) between 2003 and 2004. MAIN OUTCOME MEASURES: Baseline prevalence of atherosclerosis risk factors, medication use, and degree of risk factor control. RESULTS: Atherothrombotic patients throughout the world had similar risk factor profiles: a high proportion with hypertension (81.8%), hypercholesterolemia (72.4%), and diabetes (44.3%). The prevalence of overweight (39.8%), obesity (26.6%), and morbid obesity (3.6%) were similar in most geographic locales, but was highest in North America (overweight: 37.1%, obese: 36.5%, and morbidly obese: 5.8%; P<.001 vs other regions). Patients were generally undertreated with statins (69.4% overall; range: 56.4% for cerebrovascular disease to 76.2% for CAD), antiplatelet agents (78.6% overall; range: 53.9% for > or =3 risk factors to 85.6% for CAD), and other evidence-based risk reduction therapies. Current tobacco use in patients with established vascular disease was substantial (14.4%). Undertreated hypertension (50.0% with elevated blood pressure at baseline), undiagnosed hyperglycemia (4.9%), and impaired fasting glucose (36.5% in those not known to be diabetic) were common. Among those with symptomatic atherothrombosis, 15.9% had symptomatic polyvascular disease. CONCLUSION: This large, international, contemporary database shows that classic cardiovascular risk factors are consistent and common but are largely undertreated and undercontrolled in many regions of the world.
Aged↗
Telomere length of normal leukocytes is affected by a functional polymorphism of hTERT.
Transcriptional regulation of human telomerase reverse transcriptase (hTERT), a catalytic subunit of telomerase, is essential for telomerase activity associated with telomere length. In this study, we investigated the effects of a (-1327)T/C polymorphism within the hTERT promoter region on the hTERT promoter activity and leukocyte telomere length in normal individuals. The promoter activity in the (-1327)T-sequence was significantly higher than that in the (-1327)C-sequence (p = 0.0004). For leukocyte telomere length, the (-1327)T-allele carriers had significantly longer than the (-1327)T-allele non-carriers (p = 0.0007). Also, there was no age-related shortening in leukocyte telomere length in the (-1327)T/T (p = 0.6633) and (-1327)T/C subjects (p = 0.1691), whereas there was clear age-related telomere shortening in the (-1327)C/C subjects (p = 0.0117). These findings suggest that the functional (-1327)T/C polymorphism of hTERT is associated with leukocyte telomere length in normal individuals.
Base Sequence↗
Increase in circulating endothelial precursors by atorvastatin in patients with systemic sclerosis.
OBJECTIVE: To evaluate whether atorvastatin can increase bone marrow-derived circulating endothelial precursors (CEPs) and improve the vascular symptoms in patients with systemic sclerosis (SSc; scleroderma). METHODS: The study was designed as an open-label, prospective study involving 14 patients with SSc who received 10 mg/day of atorvastatin for 12 weeks and were followed up for the subsequent 4 weeks. CEPs were quantified at weeks 0 (pretreatment), 4, 8, 12 (during treatment), and 16 (posttreatment) by cell sorting followed by 3-color flow cytometry. Raynaud's phenomenon variables, global measures, and psychological scales as well as circulating angiogenic factors and endothelial activation/injury markers were serially assessed. The potential of CEPs to differentiate into mature endothelial cells was examined in cultures with angiogenic stimuli. RESULTS: None of the patients experienced an adverse event, but 1 dropped out because of an excessive decrease in serum total cholesterol. Atorvastatin treatment resulted in a 1.7- to 8.0-fold increase in CEPs from baseline levels (P < 0.0001), but the numbers returned to within baseline levels at posttreatment. However, 8 patients (62%) experienced a gradual decrease in the number of CEPs, even while taking atorvastatin. Variables indicating the extent of Raynaud's phenomenon improved significantly, and up-regulated levels of angiogenic factors and vascular endothelial activation/injury markers decreased significantly during atorvastatin treatment. These variables returned to within baseline levels after discontinuation of the drug. In contrast, atorvastatin failed to improve the in vitro maturation potential of CEPs. CONCLUSION: The results of this pilot study suggest that atorvastatin treatment can increase CEPs and may be effective in improving Raynaud's phenomenon, even in SSc patients who have CEP dysfunction intrinsically.
Adult↗
Pneumocystis jiroveci pneumonia associated with low-dose methotrexate treatment for rheumatoid arthritis: report of two cases and review of the literature.
Low-dose methotrexate (MTX) therapy is widely used for rheumatoid arthritis (RA) because of its favorable efficacy and toxicity profile. Although Pneumocystis jiroveci pneumonia (PCP) is most often seen in severely immunosuppressed patients, PCP complicating low-dose MTX therapy for RA has been reported to sometimes occur. We herein report two cases of patients who developed PCP during treatment with low-dose MTX, and discuss the importance of prophylaxis for this opportunistic infection.
Aged↗
Lineage-specific expression of granulocyte colony-stimulating factor and thrombopoietin receptors in terminally differentiated hematopoietic cells.
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Blood Platelets↗
Successful management of liver injury caused by imatinib mesylate in a patient with previously untreated chronic myelogenous leukemia in the chronic phase.
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Antineoplastic Agents↗
Excretion of cytosine arabinoside in saliva after its administration at high doses.
High-dose cytosine arabinoside (cytarabine) is widely used, either alone or in combination with other chemotherapeutic agents, for the treatment of refractory hematological malignancies. Its pharmacology in plasma and cerebrospinal fluid has been extensively examined. In this study, we measured the concentration of cytarabine in saliva of nine patients with hematological malignancies who received high-dose cytarabine. Cytarabine at a dose of 3 g/m was administered i.v. over 2 h. Saliva samples were collected before initiating cytarabine infusion, within 15 min after the completion of infusion and 2 or 4 h after infusion. The concentration of cytarabine was measured by HPLC methods. All nine patients showed a detectable level of cytarabine in saliva within 15 min after the completion of infusion (0.58+/-0.48 microg/ml), which was equivalent to 5% of its plasma concentration; however, the drug was no longer detectable in saliva thereafter. These findings suggest that cytarabine is excreted in saliva during and shortly after its administration at a high dose.
Adult↗
Gorog Thrombosis Test: analysis of factors influencing occlusive thrombus formation.
We used the Gorog Thrombosis Test to analyze the factors influencing the occlusion time, which represents platelet activation and subsequent occlusive thrombus formation, in 132 healthy Japanese volunteers (116 men, 16 women; mean age, 45.0 +/- 12.0 years). The Gorog Thrombosis Test was designed to evaluate platelet aggregation and thrombolytic activity under a high shear stress condition (175 dynes/cm) in a native blood sample in vitro. The mean +/- SD occlusion time was 154.8 +/- 64.7 s (men, 153.4 +/- 64.2 s and women, 165.4 +/- 56.5 s). The occlusion time was inversely correlated with von Willebrand factor ristocetin cofactor activity (VWF:Rco) (r = -0.242, P = 0.0055) and von Willebrand factor antigen (r = -0.230, P = 0.0080). The mean occlusion time in the group with VWF:Rco of at least 170% (137 s) was significantly shorter than that in the group with VWF:Rco less than 170% (156 s, P < 0.05). Platelet counts, other coagulation markers and smoking showed no significant correlations with occlusion time. Red blood cells (r = -0.177, P = 0.0365), hemoglobin (r = -0.191, P = 0.0245) and hematocrit (r = -0.182, P = 0.0329) also showed inverse correlations with the occlusion time. This report is the first to clearly demonstrate the role of von Willebrand factor in the formation of occlusive thrombi in the Gorog Thrombosis Test.
Adult↗
Possible involvement of allogeneic antigens recognised by donor-derived CD4 cytotoxic T cells in selective GVL effects after stem cell transplantation of patients with haematological malignancy.
Cytotoxic T lymphocyte (CTL) lines specific for allogeneic antigens were generated by in vitro stimulation of donor-derived peripheral blood mononuclear cells obtained from patients who received human leucocyte antigen (HLA)-matched allogeneic haematopoietic stem cell transplantation (HSCT). One of the allogeneic antigen-specific CD4+ CTL lines, CTL-A, generated from a patient with T cell acute lymphoblastic leukaemia, recognised HLA-DPB1*0501-positive Epstein-Barr virus-immortalised human B cell line (EBV-B cells), phytohaemagglutinin blasts and leukaemia cells, but not interferon-gamma (IFN-gamma) treated HLA-DPB1*0501-positive fibroblasts, indicating that this CD4+ T-cell line recognised a minor histocompatibility antigen (mHa) that is preferentially expressed in haematopoietic cells in an HLA-DPB1*0501-restricted manner. The other CD4+ CTL line, CTL-B, generated from a patient with chronic myeloid leukaemia, recognised mismatched HLA-DQB1*0303 on EBV-B cells and phytohaemagglutinin (PHA) blasts. Interestingly, this CTL line did not recognise IFN-gamma-treated recipient's skin fibroblasts, as HLA-DQ was merely upregulated even after IFN-gamma stimulation in non-haematopoietic cells including fibroblasts, endothelial cells and hepatocytes. These results suggest that these CD4 positive CTLs, specific for mismatch HLA-DQ and mHa that are preferentially expressed on haematopoietic cells, may play an important role in induction of selective graft-versus-leukaemia effect without development of graft-versus-host disease after allogeneic HSCT.
CD4-Positive T-Lymphocytes↗
Neurogenic potential of progenitors derived from human circulating CD14+ monocytes.
We previously reported a primitive cell fraction derived from human circulating CD14+ monocytes, named monocyte-derived multipotential cells (MOMC), that can differentiate along mesenchymal lineages, including bone, cartilage, fat, skeletal muscle and cardiac muscle. In this study, we investigated whether MOMC can differentiate into the neuronal lineage. MOMC were fluorescently labelled and cocultivated with a primary culture of rat neurons for up to 4 weeks. The protein and gene expressions of neuron-specific markers in the human MOMC were evaluated over time using immunohistochemistry, in situ hybridization and reverse transcription followed by PCR. Shortly after cocultivation with rat neurons, nearly all the MOMC expressed early neuroectodermal markers, Mash1, Neurogenin2 and NeuroD, together with nestin, an intermediate filament expressed in neurogenesis. After 14 days of coculture, a subpopulation of MOMC displayed a multipolar morphology with elongated neurites and expressed mature neuron-specific markers, including neurofilament, microtubule-associated protein type 2, beta3-tubulin, NeuN and Hu. Transdifferentiation of monocytes into the neuroectodermal lineage was shown by the simultaneous expression of proneural markers and CD45/CD14 early in the differentiation process. The cocultivated MOMC retained their proliferative capacity for at least 16 days. Finally, the neuronal differentiation of MOMC was observed when they were cultured with neurons without cell-to-cell contact. The capacity of MOMC to differentiate into both mesodermal and neuroectodermal lineages suggests that circulating CD14+ monocytes are more multipotential than previously thought.
Animals↗