Akio Urabe

A sensitive sandwich ELISA for measuring thrombopoietin in human serum: serum thrombopoietin levels in healthy volunteers and in patients with haemopoietic disorders

A sensitive sandwich enzyme‐linked immunosorbent assay (ELISA) has been established to estimate serum thrombopoietin (TPO) concentrations in healthy volunteers and patients with haemopoietic disorders. The ELISA uses a mouse monoclonal antibody (Ab) as the capture Ab and a biotinylated rabbit polyclonal Ab as the detector. The ELISA was reproducible, highly sensitive and specific for human TPO. The coefficients of intra‐ and inter‐assay variation were from 3.0% to 4.9% and from 5.9% to 6.1%, respectively. The quantitative limit of the ELISA was 0.09 fmol/ml in serum. The quantitative limit was lower than the normal level. The dose–response curves of serum samples from healthy volunteers and patients with haemopoietic disorders were parallel to the standard curves. The ELISA did not cross‐react with a variety of blood components and cytokines to produce false‐positive results.

A Multicenter, Open-Label Clinical Study of Micafungin (FK463) in the Treatment of Deep-seated Mycosis in Japan

The efficacy and safety of micafungin (FK463), which is a new lipopeptide antifungal agent of the echinocandin class and is active against both Aspergillus and Candida species, were investigated in patients with deep-seated mycosis in this study. 70 patients were treated with micafungin 12.5–150 mg/d intravenously for up to 56 d. The overall clinical response rates were 60% (6/10) in invasive pulmonary aspergillosis, 67% (6/9) in chronic necrotizing pulmonary aspergillosis, 55% (12/22) in pulmonary aspergilloma, 100% (6/6) in candidemia, and 71% (5/7) in esophageal candidiasis. The response rates for patients with prior antifungal treatment which was considered ineffective or toxic, were similar to rates for patients without prior treatment. Mycological eradication was observed in patients infected with Aspergillus fumigatus, Aspergillus flavus, Aspergillus terreus, Aspergillus niger, Candida albicans, Candida glabrata, or Candida krusei. Adverse events related to micafungin were reported in 21 patients (30%), and there was no dose-related occurrence of any adverse event. It is concluded that treatment with micafungin as monotherapy seems to be effective and safe in patients with deep-seated mycosis.

Treatment of Myelodysplastic Syndromes with Recombinant Human Granulocyte Colony-Stimulating Factor: A Preliminary Report

PURPOSE The expansion of an abnormal hemopoietic stem cell line is responsible for the myelodysplastic syndromes, which are characterized by pancytopenias, often resulting in lethal infections. Cloned granulocyte colony-stimulating factor (G-CSF) was recently shown to enhance the growth and differentiation of normal granulocyte progenitor cells in vitro. The aim of our study was to examine the effects of recombinant human G-CSF in patients with myelodysplastic syndromes. PATIENTS AND METHODS Four patients with myelodysplastic syndromes and one patient with smoldering acute myelogenous leukemia following the occurrence of a myelodysplastic syndrome received recombinant human G-CSF by intravenous infusion for six days. Patients received different dosage levels (50 to 1,600 micrograms/m2). RESULTS A response was seen in all patients, with an increase in both immature myeloid cells in the bone marrow and mature granulocytes in the peripheral blood. The dose levels that could stimulate granulocytopoiesis differed among patients. CONCLUSION These results suggest that, at least in some cases of myelodysplastic syndromes, granulocytopenia can be improved by G-CSF, although it still remains to be determined whether the increase in the number of granulocytes is due to the differentiation and maturation of the myelodysplastic clone or restoration of a residual normal clone.

Helicobacter pylori infection is significantly associated with metabolic syndrome in the Japanese population.

BACKGROUND:Metabolic syndrome comprises a cluster of metabolic abnormalities leading to insulin resistance and atherosclerosis, and Helicobacter pylori is thought to be a contributing factor.AIM:We examined the association between H. pylori infection and metabolic syndrome in a large Japanese population.METHOD:Consecutive asymptomatic subjects that underwent a complete medical survey in our institute between April 2006 and March 2007 were recruited, and a total of 5,488 men and 1,906 women were cross-sectionally studied. The association of H. pylori serostatus with traditional atherosclerosis risk factors was investigated by multiple linear regression analysis. Independent and significant factors affecting metabolic syndrome were determined by multiple logistic regression analysis.RESULTS:H. pylori seropositivity significantly increased with age in both men and women. H. pylori seropositivity was significantly higher in cases with metabolic syndrome compared with those without metabolic syndrome (P < 0.001). There was a significant and independent association between H. pylori seropositivity and metabolic syndrome (OR 1.39, 95% CI 1.18–1.62, P < 0.001) by multiple logistic regression analysis. H. pylori seropositivity was significantly associated with higher systolic blood pressure (β coefficient = 1.03, P = 0.014), lower high-density lipoprotein (HDL)-cholesterol level (β coefficient = −2.00, P < 0.001), and higher LDL-cholesterol level (β coefficient = 2.21, P = 0.005) by multiple linear regression analysis.CONCLUSION:In a large Japanese population, H. pylori infection was significantly associated with metabolic syndrome.

Light and Moderate Alcohol Consumption Significantly Reduces the Prevalence of Fatty Liver in the Japanese Male Population

OBJECTIVES:The effect of alcohol consumption on the liver is controversial. Recent reports have suggested that moderate alcohol consumption decreases the prevalence of elevated alanine aminotransferase levels. The role of alcohol consumption in the development of fatty liver (FL), however, has not been studied definitively. The aim of this study was to examine the association between alcohol consumption and FL in a large Japanese population.METHODS:A total of 7,431 asymptomatic male subjects who underwent a complete medical survey in our institute between May 2007 and July 2008 were recruited. Cases positive for hepatitis B or C viruses, potential hepatotoxic drug intake, or under treatment for metabolic disorders were excluded. FL was defined by ultrasonography. Visceral and subcutaneous adipose tissues (VAT and SAT) were measured by computed tomography. Independent and significant predictors associated with FL were determined by multiple logistic regression analysis.RESULTS:Of the initial study candidates, 130 (1.7%) were positive for hepatitis B and 66 (0.8%) were positive for hepatitis C. On the basis of the inclusion and exclusion criteria, 5,599 men (50.9±8.1 years) were studied cross-sectionally. Light (40–140 g/week) and moderate (140–280 g/week) alcohol consumption significantly and independently reduced the likelihood of FL (odds ratio=0.824 and 0.754, 95% confidence interval=0.683–0.994 and 0.612–0.928, P=0.044 and 0.008, respectively) by multivariate analysis after adjusting for potential confounding variables. VAT, SAT, low-density lipoprotein, triglycerides, and fasting blood glucose were significant predictors of the increased prevalence of FL, whereas age was a predictor of the decreased prevalence of FL.CONCLUSIONS:The prevalence of FL was significantly and independently decreased by light and moderate alcohol consumption in men of an asymptomatic Japanese population.

Helicobacter pylori infection significantly increases insulin resistance in the asymptomatic Japanese population.

Background:  Helicobacter pylori infection has been shown to contribute to atherosclerosis and cardiovascular diseases. Insulin resistance is the pathophysiologic background of the clinical features of atherosclerosis and cardiovascular diseases. We examined the association between H. pylori infection and insulin resistance in a large Japanese population.

Efficacy of granulocyte colony‐stimulating factor in the treatment of acute myelogenous leukaemia: a multicentre randomized study

Summary. To investigate the efficacy and safety of granulocyte colony‐stimulating factor (G‐CSF) in patients with acute myelogenous leukaemia, a multicentre randomized study was performed. From October 1993 to September 1996, 270 patients with newly diagnosed acute myelogenous leukaemia were randomized to G‐CSF or control groups after remission induction therapy. The G‐CSF group received G‐CSF (Filgrastim) from 48 h after the completing chemotherapy until the absolute neutrophil count exceeded 1·5 × 109/l. The control group did not receive G‐CSF unless severe infection occurred. There were 245 evaluable patients (120 and 125 in the G‐CSF and control groups respectively). The complete remission rate was similar in the G‐CSF and control groups (80·8% versus 76·8%), as was the 5‐year probability of disease‐free survival (34·5% versus 33·6%) and overall survival (42·7% versus 35·6%). Neutrophil recovery was significantly faster in the G‐CSF group than in the control group (12 d versus 18 d, P = 0·0001). The median duration of febrile neutropenia was significantly shorter in the G‐CSF group than in the control group (3 d versus 4 d, P = 0·0001). In conclusion, prophylactic administration of G‐CSF after remission induction therapy for acute myelogenous leukaemia is safe and useful even in patients without infection on completing chemotherapy.

Randomized Trial of Cefepime Monotherapy or Cefepime in Combination with Amikacin as Empirical Therapy for Febrile Neutropenia

A multicenter open randomized trial was conducted to compare cefepime monotherapy with cefepime/amikacin combination (dual) therapy in treating febrile neutropenic patients with hematologic disorders. Among the 189 evaluable patients, 5.8% had microbiologically and 10.6% had clinically documented infections. Excellent response was seen in 32.6% and 45.7% of monotherapy and dual therapy recipients, respectively, at day 3 (P=.065). At day 3, patients with neutrophil counts of <500/ mu L receiving dual therapy had a better response than did those receiving monotherapy (45% vs. 27.6%; P=.024). The same was true for patients with leukemia. Adverse events were minimal, and early death was observed in 7 patients in the dual therapy group and 5 patients in the monotherapy group. Overall, cefepime monotherapy is as effective as dual therapy for the initial treatment of febrile neutropenic patients. Further study is warranted for patients with severe neutropenia and leukemia who may benefit from dual therapy.

Effects of type β transforming growth factors on haematopoietic progenitor cells

The effects of type β transforming growth factors (TGF‐βs) on normal human and murine haematopoietic progenitor cells were examined using bone marrow colony assays. In erythroid colony assays, TGF‐β1 inhibited human CFU‐E derived colony formation, BFU‐E derived burst formation, and murine BFU‐E derived burst formation in a dose dependent manner between 0.1 and 5.0 ng/ml. However, murine CFU‐E derived colony formation was unaffected even at a concentration of 5.0 ng/ml TGF‐β1. In myeloid colony assays, different sensitivity of progenitor cells to the inhibitory effects of TGF‐βs was observed between both species. TGF‐β1 inhibited murine granulocyte‐macrophage colony (GM‐colony) formation and granulocyte colony (G‐colony) formation in a dose dependent manner between 0.1 and 5.0 ng/ml, but had no remarkable effects on human GM‐colony and G‐colony formation. TGF‐β2 also had similar inhibitory effects on haematopoietic progenitor cells, while its inhibitory effect was less potent than that of TGF‐β1. Thus our data suggest that TGF‐β may be involved in negative regulation of haematopoiesis and that its inhibitory action may be restricted in lineage and/or species specific manner.

1α,25-Dihydroxy vitamin D3 (calcitriol) stimulates proliferation of human circulating monocytes in vitro

Previous studies demonstrated that human circulating monocytes can proliferate in vitro when incubated with lectin‐induced factor(s) from lymphocytes [(1985) Biochem. Biophys. Res. Commun., in press]. This study shows that human monocytes were induced to proliferate when incubated with 1α,25‐dihydroxy vitamin D3 (calcitriol) at physiological concentrations. The optimal dose was about 10 nM. Proliferative activity was examined both by measuring the [su3H]thymidine incorporation and by counting cell nuclei. Among other derivatives of vitamin D3, 1α,24 R‐dihydroxyvitamin D3 and 1α,24R,25‐trihydroxyvitamin D3 stimulated mitotic activity of monocytes. Addition of both calcitriol and lectin‐stimulated lymphocyte‐conditioned medium to the monocyte culture had an additional effect on the mitotic activity of monocytes.