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Abstract: Dual two-phase intermetallic alloy that has an alloy composition of Ni75Al9V13Nb3 and is composed of geometrically close packed (GCP) Ni3Al (L12) and Ni3V (D022) phases was studied, focusing on the effect of NbC addition on high-temperature tensile properties. The two-phase microstructures defined by primary Ni3Al precipitates and eutectoid region consisting of Ni3Al and Ni3V phases were kept and were dispersed by Nb2C particles regardless of NbC content. EPMA analysis showed that alloy compositions in matrix of the NbC added alloy were different from those in the base alloy. The positive temperature dependence of flow strength was observed for all NbC added alloys. In low temperature range the maximum strengthening took place at 1at.% NbC content. On the other hand, tensile elongation increased with increasing NbC content up to 1at.% NbC content and gradually decreased at NbC content over 1at.% content in whole temperature ranges. Also, the NbC addition resulted in change of the fracture mode from brittle transgranular fracture to ductile transgranular fracture in low temperature range, and from brittle intergranular fracture to ductile transgranular in high temperature range. Possible mechanisms responsible for the strengthening and ductilization by NbC addition were discussed, based on the behavior of C solutes in the matrix, which were released from the charged NbC carbides. [Copyright &y& Elsevier]

Abstract: Dual two-phase intermetallic alloy that has an alloy composition of Ni75Al9V13Nb3 and is composed of geometrically close packed (GCP) Ni3Al (L12) and Ni3V (D022) phases was studied, focusing on the effect of TiC addition on high-temperature tensile properties. The two-phase microstructures defined by primary Ni3Al precipitates and eutectoid region consisting of Ni3Al and Ni3V phases were kept and were dispersed by TiC particles. EPMA analysis showed that alloy compositions in matrix of the TiC added alloy were different from those in the base alloy. The positive temperature dependence of flow strength was observed for all TiC added alloys. In low temperature range the maximum strengthening took place at 1at.% TiC content. On the other hand, tensile elongation increased with increasing TiC content up to 1at.% TiC content and was independent of TiC content over 1at.% in whole temperature ranges. Also, the TiC addition resulted in change of the fracture mode from brittle transgranular fracture to ductile transgranular fracture in low temperature range, and from brittle intergranular fracture to ductile transgranular fracture in high-temperature range. Possible mechanisms responsible for the strengthening and ductilization by TiC addition were interpreted, based on the behavior of C and Ti solutes, and Nb solute in the matrix, which were decomposed from TiC and affected by TiC addition, respectively. [Copyright &y& Elsevier]

Idiopathic dilated cardiomyopathy (IDC) is a myocardial disease characterised by ventricular dilatation, impaired contractility, and the symptoms of congestive heart failure. Although the causes of IDC remain uncertain, much interest has been focused on the enteroviral infection in the myocardium in the pathogenesis of this disease. Enteroviral RNA has been demonstrated in the myocardium at all stages of IDC. Recent studies using sequence analysis of enteroviral polymerase chain reaction (PCR) products have shown that the viruses detected in hearts of patients with IDC are coxsackie B. In addition, active coxsackieviral RNA replication in the myocardium has been demonstrated by strand-specific detection of viral RNA. Viral antigen has also been found in hearts with IDC by immunohistochemical techniques. In tissue culture experiments and transgenic mice, it has been shown that restricted coxsackieviral RNA replication, and not infectious virus progeny, in the myocardium can impair cardiac contractile function and lead to dilated cardiomyopathy. Coxsackieviral RNA in the myocardium can be a marker of a poor clinical outcome after partial left ventriculectomy, and might influence prognosis after heart transplantation. Therefore, there is a therapeutic need to detect replicating coxsackieviral RNA in the myocardium, and a specific therapy for coxsackie B viruses is indicated in the management of patients with virus-positive IDC. [ABSTRACT FROM AUTHOR]

An abstract of the article "Intranasala Administration of atrial natriutetic peptide attenuates left ventricular remodeling and dysfunction associated with acute myocardial infarction in rats," by T. Kono and colleagues is presented.

Abstract: Objective: To determine the electrophysiological characteristics of frontotemporal dementia (FTD) and the distinction with Alzheimer’s disease (AD). Methods: We performed analyses of global field power (GFP) which is a measure of whole brain electric field strength, and EEG neuroimaging analyses with sLORETA (standardized low resolution electromagnetic tomography), in the mild stages of FTD (n =19; mean age=68.11±7.77) and AD (n =19; mean age=69.42±9.57) patients, and normal control (NC) subjects (n =22; mean age=66.13±6.02). Results: In the GFP analysis, significant group effects were observed in the delta (1.5–6.0Hz), alpha1 (8.5–10.0Hz), and beta1 (12.5–18.0Hz) bands. In sLORETA analysis, differences in activity were observed in the alpha1 band (NC>FTD) in the orbital frontal and temporal lobe, in the delta band (AD>NC) in widespread areas including the frontal lobe, and in the beta1 band (FTD>AD) in the parietal lobe and sensorimotor area. Conclusions: Differential patterns of brain regions and EEG frequency bands were observed between the FTD and AD groups in terms of pathological activity. Significance: FTD and AD patients in the early stages displayed different patterns in the cortical localization of oscillatory activity across different frequency bands. [Copyright &y& Elsevier]

Aims: S100A8/A9 is expressed in activated monocytes/macrophages and assumed to be heavily involved in the pathogenesis of acute inflammation. Although several studies have asserted that S100A8/A9 has a proinflammatory function, the exact biological function of S100A8/A9 is yet to be described. We examined the anti-inflammatory effects of S100A8/A9 on experimental autoimmune myocarditis (EAM) in rats.Methods and Results: Experimental autoimmune myocarditis was induced in Lewis rats by immunization with porcine cardiac myosin. The recombinant (R-) S100A8/A9 was injected intraperitoneally into EAM rats. R-S100A8/A9 attenuated the severity of myocarditis, as evidenced by echocardiographic and histological findings. In addition, we found that not only the mRNA expression of proinflammatory cytokines [interleukin (IL)-1beta, IL-6, and tumour necrosis factor (TNF)-alpha] in the myocardium, but also their serum concentrations were suppressed in EAM rats treated with R-S100A8/A9. Nuclear factor-kappa B expression in inflammatory cells was also suppressed in the treated rats. To elucidate the mechanistic function of S100A8/A9 on proinflammatory cytokines in vivo, we used an ELISA on the supernatant of homogenized heart tissue treated with R-S100A8/A9. The findings revealed high-affinity binding of R-S100A8/A9 with IL-1beta, IL-6, and TNF-alpha in the myocardium, suggesting the trapping of proinflammatory cytokines by R-S100A8/A9.Conclusion: S100A8/A9 attenuates EAM through modulation of the proinflammatory cytokine network. [ABSTRACT FROM AUTHOR]

To better define the reported increased digitalis-like immunoreactive substances (DLIS) in neonatal plasma, we studied the relation among plasma DLIS level, blank intensity (BLK-I) value at FPIA measurement and plasma total bilirubin level.The DLIS levels were measured in 10 neonates with or without jaundice and 10 infants in good health, using fluorescence polarization immunoassay (FPIA) and microparticle enzyme immunoassay (MEIA). BLK-I value and plasma total bilirubin level were also measured simultaneously.In neonates with jaundice, DLIS using FPIA, BLK-I and total bilirubin level were 0·58 ±0·13 ng/mL, 2598 ± 408, and 17·98 ± 1·13 mg/dL, respectively, before phototherapy, and 0·33 ±0·06 ng/mL, 1886 ± 237, and 15·16 ± 2·07 mg/dL after phototherapy. Corresponding values in neonates without jaundice were (DLIS: 0·34 ±0·04 ng/mL; BLK-I: 1,764 ± 278; total bilirubin: 10·37 ± 4·54 mg/dL); in healthy infants (0·12 ±0·06 ng/mL, 400·7 ± 4·6 and 0·42 ± 0·13 mg/dL, respectively) and in healthy volunteers (0·10 ±0·07 ng/mL, 403·1 ± 8·4, and 0·58 ± 0·30 mg/dL, respectively). Using MEIA, DLIS was not detected in 10 neonates, 10 infants and 20 healthy volunteers.A fluorescent compound related to bilirubin increased the BLK-I value in the measurement of neonatal plasma using FPIA. The fluorescence was not the result of endogenous digitalis-like factors. [ABSTRACT FROM AUTHOR]

An abstract of the article "Low-dose rather than high-dose erythropoietin may be effective in a rat model of dilated cardiomyopathy that is not anaemic," by T. Kono and colleagues is presented

BACKGROUND: Cardiac microangiopathy may be involved in the development of heart failure in diabetes mellitus. OBJECTIVE: To evaluate the effect of angiotensin II receptor blockade on cardiac function and fine structures in diabetes. METHODS: Male Otsuka Long-Evans Tokushima Fatty (OLETF) rats (n = 30), a model of spontaneously developing diabetes mellitus, and their diabetes resistant counterparts (n = 20) were used. At 30 weeks of age, when the OLETF rats show hyperglycaemic obesity with hyperinsulinaemia, the animals were divided into two groups and given candesartan, an angiotensin II receptor blocker, 0.2 mg/kg/day, or vehicle for six weeks. Capillary density was evaluated in the left ventricular myocardium by electron microscopy, matrix metalloproteinase (MMP) activity by zymography, and cytokines by reverse transcriptase polymerase chain reaction. RESULTS: Compared with the control rats, the OLETF rats at 36 weeks showed decreased peak negative dP/dt (mean (SD): 2350 (250) v 3492 (286) mm Hg/s) and increased cardiomyocyte diameter (24.3 (0.6) v 18.9 (0.6) microm) (both p < 0.05). Thickening of the capillary basement membranes and decreased capillary density were observed. Angiotensin receptor blockade improved almost all the haemodynamic variables, and the histological findings became similar to those of the controls. Angiotensin receptor blockade also activated MMP-2 and prevented an increase of inflammatory cytokines, especially interleukin (IL)-1beta and IL-6, in the diabetic heart. CONCLUSIONS: Angiotensin II receptor blockade preserved left ventricular diastolic function. It was also potent at improving cardiomyocyte diameter and the thickening of the capillary basement membrane, increasing MMP-2 activity, and decreasing inflammatory cytokines. With all these changes, candesartan could contribute to cardioprotection in diabetes mellitus. [ABSTRACT FROM AUTHOR]