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Macrophage inhibitory cytokine 1 (MIC-1), which is overproduced in various human cancers and associated with cachexia, acts on the hypothalamus to suppress appetite and reduce body weight. We investigated the mechanisms through which MIC-1 affects bile acid metabolism and gallstone formation, which are poorly understood. Over 6 weeks, male C57BL/6 mice fed either standard chow or a lithogenic diet were intraperitoneally injected with phosphate-buffered saline (PBS) or MIC-1 (200 μg/kg/week). Among lithogenic diet-fed mice, MIC-1 treatment resulted in increased gallstone formation compared with PBS treatment. Compared with PBS treatment, MIC-1 treatment decreased hepatic cholesterol and bile acid levels and reduced expression of HMG-CoA reductase (HMGCR), the master cholesterol metabolism regulator sterol regulatory element-binding protein 2, cholesterol 7α-hydroxylase (CYP7A1), mitochondrial sterol 27-hydroxylase, and oxysterol 7α-hydroxylase. Compared with PBS treatment, MIC-1 treatment had no effect on small heterodimer partner, farnesoid X receptor, or pregnane X receptor expression, and extracellular signal-related kinase and c-Jun N-terminal kinase phosphorylation decreased, suggesting that these factors do not contribute to the MIC-1-induced reduction in CYP7A1 expression. Compared with PBS treatment, MIC-1 treatment increased AMP-activated protein kinase (AMPK) phosphorylation. Treatment with the AMPK activator 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR) reduced CYP7A1 and HMGCR expression, whereas the AMPK inhibitor Compound C reversed MIC-1-induced reductions in CYP7A1 and HMGCR expression. Furthermore, in MIC-1-treated mice, total biliary cholesterol levels increased together with increased ATP-binding cassette subfamily G (ABCG)5 and ABCG8 expression. Compared with PBS treatment, MIC-1 treatment did not affect expression of liver X receptors α and β, liver receptor homolog 1, hepatocyte nuclear factor 4α, or NR1I3 (also known as constitutive androstane receptor), which are upstream of ABCG5/8; however, MIC-1 treatment increased ABCG5/8 expression and promoter activities. Our study indicates that MIC-1 influences gallstone formation by increasing AMPK phosphorylation, reducing CYP7A1 and HMGCR expression, and increasing ABCG5 and ABCG8 expression.

Phosphate overload contributes to mineral bone disorders that are associated with crystal nephropathies. Phytate, the major form of phosphorus in plant seeds, is known as an indigestible and of negligible nutritional value in humans. However, the mechanism and adverse effects of high-phytate intake on Ca2+ and phosphate absorption and homeostasis are unknown. Here, we show that excessive intake of phytate along with a low-Ca2+ diet fed to rats contributed to the development of crystal nephropathies, renal phosphate wasting, and bone loss through tubular dysfunction secondary to dysregulation of intestinal calcium and phosphate absorption. Moreover, Ca2+ supplementation alleviated the detrimental effects of excess dietary phytate on bone and kidney through excretion of undigested Ca2+-phytate, which prevented a vicious cycle of intestinal phosphate overload and renal phosphate wasting while improving intestinal Ca2+ bioavailability. Thus, we demonstrate that phytate is digestible without a high-Ca2+ diet and is a risk factor for phosphate overloading and for the development of crystal nephropathies and bone disease.

This paper proposes a quasi-resonant boost half-bridge dc–dc converter with high power conversion efficiency and a wide input voltage range for a photovoltaic micro-inverter. The proposed converter has a combined structure of a boost-integrated half-bridge converter on the primary side of the transformer and a voltage doubler with a snubber capacitor on the secondary side. By using the quasi-resonance techniques, it achieves zero-voltage switching (ZVS) turn-on and low turn-off losses for the switches, as well as ZVS turn-on for the diodes. In addition, the proposed converter has no dc-magnetizing current for the transformer due to the dc-blocking capacitor, and it doubles the voltage gain with half the voltage stress of diodes through the voltage doubler. The effectiveness of the converter was verified with a 300-W prototype with an input voltage range of 13–50 V, an output voltage of 400 V, and a switching frequency of 50 kHz. The experimental results show that the converter had more than 90.0% power conversion efficiency for the output power range of ∼300 W, and its maximum power conversion efficiency was 97.5% for an output power of 160 W. [ABSTRACT FROM AUTHOR]

This paper proposes a new bidirectional buck–boost converter, which is a key component in a photovoltaic and energy storage system (ESS). Conventional bidirectional buck–boost converters for ESSs operate in discontinuous conduction mode (DCM) to achieve zero-voltage switching turn-on for switches. However, operation in DCM causes high ripples in the output voltage and current, as well as low power-conversion efficiency. To improve the performance of the conventional converter, the proposed converter has a new combined structure of a cascaded buck–boost converter and an auxiliary capacitor. The combined structure of the proposed converter reduces the output current ripple by providing a current path and the efficiency is increased. A prototype was built and tested to verify the effectiveness of the converter. The proposed converter has a maximum efficiency of 98%, less than ${\text{5.14}}{\ \text{V}}_{{\text{p.p}}}$ of output voltage ripple, and less than ${\text{7.12}}{\ \text{A}}_{{\text{p.p}}}$ of output current ripple. These results were obtained at an input voltage of 160 V, switching frequency of 45 kHz, output voltage of 80–320 V, and output power of 16–160 W. The experimental results show that the proposed converter has improved performance compared to the conventional converter. [ABSTRACT FROM AUTHOR]

Tourmaline is a kind of borosilicatemineral and has spontaneous polarization property. Due to this property, it can generate a feeble current around 0.06 mA[1]. We fabricated the TiO2photoanode with different wt.% ratio of tourmaline and investigated the effect of tourmaline additive on dye sensitized solar cells (DSSCs). We carried out electrochemical impedance spectroscopy (EIS) and current density-voltage (J-V) measurement. The results showed that the electron lifetime and the power conversion efficiency of the DSSCs with TiO2photoanode containing 3wt% tourmaline were enhanced by about 42% and 20%, respectively, as compared to the DSSCs using pristine TiO2photoanode. [ABSTRACT FROM AUTHOR]

To improve performance of dye-sensitized solar cell(DSSC), thermally reduced graphene oxide(rGO) was investigated as Pt-free counter electrodes(CE) material. The DSSCs with rGO were fabrcated by simple spin coating method under different temperature and ambient atmospheres like Ar, N2and air. When the rGO CE was reduced at 450°C under the Ar atmosphere, it was obtained the power conversion efficiency of 6.02%, which showed the high catalytic activity and performance of DSSC as much as Pt. This value means the thermally reduced rGO CEs under the Ar gas will be suitable as a substitute for Pt CEs. [ABSTRACT FROM AUTHOR]

We successfully fabricated the TiO2-based photoelectrode doped with reduced graphene oxide (rGO) to improve the power conversion efficiency of dye-sensitized solar cells (DSSCs). The ratio of rGO was 0.3∼1.5 wt%. The DSSCs with the TiO2photoanode incorporated 0.3 wt% rGO showed a maximum power conversion efficiency of 6.26% which is 44% higher than the pristine TiO2photoelectrode. We concluded the introduction of rGO doped at 0.3 wt% ratio contributed to reducing the resistance of the surface and the interface of the photoelectrode from the observation of electrochemical impedance spectroscopy(EIS). [ABSTRACT FROM AUTHOR]

This paper proposes a method of improving the power-conversion efficiency of a direct-current–direct-current boost converter. The proposed method uses a passive snubber circuit, which consists of two inductors, a capacitor, and a diode, to reduce switching loss. The proposed boost converter was built and tested on 42-, 47-, and 55-in edge-lit light-emitting-diode (LED) backlight units (BLUs). The power-conversion efficiency for an input voltage of 24 V was measured as 96%, 95.1%, and 93.7% for the 42-, 47-, and 55-in edge-lit LED BLUs, respectively; these values were 2.3%, 2.2%, and 2% higher than those of the conventional boost converters in the corresponding BLUs. The proposed boost converter ensured reliable operation and high-power efficiency under a \pm10% variation of input voltage and a \pm20% variation of the passive snubber component values. [ABSTRACT FROM AUTHOR]

Background aims. Graft-versus-host disease (GvHD) remains a major complication after allogeneic hematopoietic cell transplantation (HCT). Recent literature demonstrates a potential benefit of human mesenchymal stromal cells (MSC) for the treatment of refractory GvHD; however, the optimal dose remains uncertain. We set out to develop an animal model that can be used to study the effect of MSC on GvHD. Methods. A GvHD mouse model was established by transplanting C3H/he donor bone marrow (BM) cells and spleen cells into lethally irradiated BALB/c recipient mice. MSC were obtained from C3H/he mice and the C3H/10T1/2 murine MSC line. Results. The mRNA expression of Foxp3 in regional lymph nodes (LN) localized with T cells was markedly increased by the addition of C3H10T1/2 cells in a real-time polymerase chain reaction (PCR). Using a mixed lymphocyte reaction, we determined the optimal splenocyte proliferation inhibition dose (MSC:splenocyte ratios 1:2 and 1:1). Three different C3H10T1/2 cell doses (low, 0.5 × 106, intermediate, 1 × 106, and high, 2 × 106) with a consistent splenocyte dose (1 × 106) were evaluated for their therapeutic potential in an in vivo GvHD model. The clinical and histologic GvHD score and Kaplan–Meier survival rate were improved after MSC transplantation, and these results demonstrated a dose-dependent inhibition. Conclusions. We conclude that MSC inhibit GvHD in a dose-dependent manner in this mouse model and this model can be used to study the effects of MSC on GvHD. [ABSTRACT FROM AUTHOR]

The article presents a study which examined the effects of various parameters such as pH, osmolarity, temperature and cations that are known to cause cell volume changes on reticulocyte enrichment, after defining a criterion for fair comparison of the experimental conditions. It was found that human factors, aside from the in vitro factors studied, can also affect reticulocyte enrichment. The best buffer composition for reticulocyte enrichment is noted.

The antibody levels against the C-terminal region of the merozoite surface protein 1 of Plasmodium vivax (PvMSP1c) were measured in 276 patients with P. vivax malaria (patient group), 320 malaria-naïve healthy individuals (control group 1), and 70 malaria-naïve individuals with various disorders (control group 2) using the immunoglobulin M (IgM) capture enzyme-linked immunosorbent assay (ELISA) and the direct sandwich ELISA. To evaluate the antibody response during relapse, 5 relapsed patients were tested using the IgM capture ELISA. The IgM antibodies were negative in 99.7% of control group 1 and in 100% of control group 2; they were positive in 90.6% of the patient group. The total antibody levels were positive in 88.4% of the patient group with the direct sandwich ELISA. The sera from the second malaria episode, i.e., relapsed patients, were 100% positive on the IgM capture ELISA. The results of this study suggest that the IgM capture ELISA may be a useful diagnostic method for P. vivax malaria for both primary infection and relapse. [ABSTRACT FROM AUTHOR]

Abstract  The magnetic method has been previously utilized to concentrate Plasmodium-infected erythrocytes without any significant influence on the viability of the parasite. We attempted, in this study, to concentrate and synchronize cultivated P. falciparum via the magnetic method. The results of this study showed that the magnetic method effectively synchronized and concentrated P. falciparum with finer demarcation capacity in the erythrocytic asexual cycle of the parasite than currently available synchronization methods. Concentration and synchronization by the magnetic method proved most effective when schizonts were dominant. Therefore, it proved necessary to enhance the synchronization efficiency of the magnetic method by first applying the method currently in use, which renders schizonts dominant. Our study also showed that the intrinsic life cycle of erythrocytic P. falciparum was slightly longer than 48 h observed in natural infection cases, and that the length of the intrinsic life cycles between various P. falciparum strains differed slightly. [ABSTRACT FROM AUTHOR]

The article provides information on a study which analyzed the erythropoietin (EPO)-independent and dependent processes to optimize the timing of EPO addition during in vitro erythropoiesis. The study used umbilical cord blood obtained from the placenta under asceptic condition in vaginal deliver with informed consent of 8 mothers from Weha Women's University in Seoul, South Korea. The research also analyzed the production efficiency of glycophorin A (GPA)-expressing cells according to the timing of EPO addition.

In a previous study, we determined the gene expression profile of both megakaryocytic and non-megakaryocytic lineage cells via serial analysis of gene expression and microarray methods, and demonstrated that Pim-1 was expressed more abundantly in megakaryocytic lineage cells. In this study, we knocked down Pim-1 in K562 cells, as well as in CD34+ cells from cord blood, via RNA interference, in order to analyze the effects of Pim-1 expression on the megakaryocytic differentiation of these cells. We then additionally overexpressed the Pim-1 genes in K562 cells, and conducted a comparison of these effects with those of RNAi cells on the course of megakaryocytic differentiation. The results of this study revealed that Pim-1 knockdown exerted no effects on commitment or differentiation toward megakaryocytic lineage, as evidenced by the detected CD41+ or CD61+ cells, or on the number of megakaryocytic colony forming units. However, Pim-1 knockdown was found to elicit a reduction in CD41+ cells with >4 n DNA content, and a concomitant increase in the fraction of cells achieving a ploidy of >4 n in the Pim-1 overexpressing population of K562 cells. Collectively, the findings of these studies indicate that the expression of Pim-1 expression is both necessary and sufficient for polyploidization, but is not critical to cytoplasmic differentiation on megakaryopoiesis. [ABSTRACT FROM AUTHOR]

This paper presents a highly efficient three-port converter to integrate energy storage (ES) and wireless power transfer (WPT) systems. The proposed converter consists of a bidirectional DC-DC converter and an AC-DC converter with a resonant capacitor. By sharing an inductor and four switches in the bidirectional DC-DC converter, the bidirectional DC-DC converter operates as a DC-DC converter for ES systems and simultaneously as a DC-AC converter for WPT systems. Here, four switches are turned on under the zero voltage switching conditions. The AC-DC converter for WPT system achieves high voltage gain by using a resonance between the resonant capacitor and the leakage inductance of a receiving coil. A 100-W prototype was built and tested to verify the effectiveness of the converter; it had a maximum power-conversion efficiency of 95.9% for the battery load and of 93.8% for the wireless charging load. [ABSTRACT FROM AUTHOR]

The basic and adaptive maximum power point tracking algorithms have been studied for distributed photovoltaic systems to maximize the energy production of a photovoltaic (PV) module. However, the basic maximum power point tracking algorithms using a fixed step size, such as perturb and observe and incremental conductance, suffer from a trade-off between tracking accuracy and tracking speed. Although the adaptive maximum power point tracking algorithms using a variable step size improve the maximum power point tracking efficiency and dynamic response of the basic algorithms, these algorithms still have the oscillations at the maximum power point, because the variable step size is sensitive to external factors. Therefore, this paper proposes an enhanced maximum power point tracking algorithm that can have fast dynamic response, low oscillations, and high maximum power point tracking efficiency. To achieve these advantages, the proposed maximum power point tracking algorithm uses two methods that can apply the optimal step size to each operating range. In the operating range near the maximum power point, a small fixed step size is used to minimize the oscillations at the maximum power point. In contrast, in the operating range far from the maximum power point, a variable step size proportional to the slope of the power-voltage curve of PV module is used to achieve fast tracking speed under dynamic weather conditions. As a result, the proposed algorithm can achieve higher maximum power point tracking efficiency, faster dynamic response, and lower oscillations than the basic and adaptive algorithms. The theoretical analysis and performance of the proposed algorithm were verified by experimental results. In addition, the comparative experimental results of the proposed algorithm with the other maximum power point tracking algorithms show the superiority of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Eosinophils are abundant in the lamina propria of the small intestine, but they rarely show degranulation in situ under steady-state conditions. In this study, using two novel mAbs, we found that intestinal eosinophils constitutively expressed a high level of an inhibitory receptor signal regulatory protein α (SIRPα)/CD172a and a low, but significant, level of a tetraspanin CD63, whose upregulation is closely associated with degranulation. Cross-linking SIRPα/CD172a on the surface of wild-type eosinophils significantly inhibited the release of eosinophil peroxidase induced by the calcium ionophore A23187, whereas this cross-linking effect was not observed in eosinophils isolated from mice expressing a mutated SIRPα/CD172a that lacks most of its cytoplasmic domain (SIRPα Cyto-/-). The SIRPα Cyto-/- eosinophils showed reduced viability, increased CD63 expression, and increased eosinophil peroxidase release with or without A23187 stimulation in vitro. In addition, SIRPα Cyto-/- mice showed increased frequencies of Annexin V-binding eosinophils and free MBP+CD63+ extracellular granules, as well as increased tissue remodeling in the small intestine under steady-state conditions. Mice deficient in CD47, which is a ligand for SIRPα/CD172a, recapitulated these phenomena. Moreover, during Th2-biased inflammation, increased eosinophil cell death and degranulation were obvious in a number of tissues, including the small intestine, in the SIRPα Cyto-/- mice compared with wild-type mice. Collectively, our results indicated that SIRPα/CD172a regulates eosinophil homeostasis, probably by interacting with CD47, with substantial effects on eosinophil survival. Thus, SIRPα/CD172a is a potential therapeutic target for eosinophil-associated diseases. [ABSTRACT FROM AUTHOR]