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We have investigated the properties of InGaZn6O9 thin films fabricated by radio frequency (RF) magnetron sputtering for the application to the electrodes in transparent thin film transistor (TTFT)....

The primary synchronization signal (PSS) and secondary synchronization signal (SSS) transmitted in the 5G are used to perform a synchronization procedure. This paper proposes an effective residual frequency offset (RFO) estimation method in a 5G new radio (NR) system. The proposed RFO estimation method applies two branches correlation using PSS and SSS sequence. This paper shows via the simulation results that the inherent property of the PSS and SSS signals is exploited for a robust RFO estimation at various delay spread of wireless environments. It is demonstrated that the proposed RFO estimation scheme is efficient for the 5G NR system.

During a Cooperation Centre for Scientific Research Relative to Tobacco (CORESTA) meeting, the in vitro toxicity testing Sub-Group (IVT SG) met to discuss the evolving field of aerosol exposure research. Given the diversity of exposure parameters and biological endpoints being used, it was considered a high priority to investigate and contextualise the responses obtained. This is particularly driven by the inability to compare between studies on different exposure systems due to user preferences and protocol differences. Twelve global tobacco and contract research companies met to discuss this topic and formulate an aligned approach on how this diverging field of research could be appropriately compared. Something that is becoming increasingly important, especially in the light of more focused regulatory scrutiny. A detailed and comprehensive survey was conducted on over 40 parameters ranging from aerosol generation, dilution and data analysis across eight geographically independent laboratories. The survey results emphasise the diversity of in vitro exposure parameters and methodologies employed across the IVT SG and highlighted pockets of harmonisation. For example, many of the biological protocol parameters are consistent across the Sub-Group. However, variables such as cell type and exposure time remain largely inconsistent. The next steps for this work will be to map parameters and system data against biological findings and investigate whether the observed inconsistencies translate into increased biological variability. The results from the survey provide improved awareness of parameters and nuances, that may be of substantial benefit to scientists in intersecting fields and in the development of harmonised approaches.

Fine dust (PM2.5) is generated from various sources, and many studies have reported on the sources of PM2.5. However, the current research on PM2.5 toxicity based on its sources is insufficient. In this study, we developed a framework for the prioritization of fine dust (PM2.5) sources on the basis of the multi-endpoint toxicities using the multi-criteria decision-making method (MCDM). To obtain the multi-endpoint toxicities of PM2.5 sources, cell mortality, reactive oxygen species (ROS), inflammation and mutagenicity were measured for diesel exhaust particles (DEP), gasoline exhaust particles (GEP), rice straw burning particles (RBP), coal combustion particles (CCP) and tunnel dust particles (TDP). The integrative toxicity score (ITS) of the PM2.5 source was calculated using MCDM, which consist of four steps: (1) defining the decision-making matrix, (2) normalization and weighting, (3) calculating the ITS (linear aggregation) and (4) a global sensitivity analysis. The indicator of cell mortality had the highest weight (0.3780) followed by inflammation (0.2471), ROS (0.2178) and mutagenicity (0.1571). Additionally, the ITS based on the sources contributing to PM2.5 resulted in the following order: DEP (0.89), GEP (0.44), RBP (0.40), CCP (0.23) and TDP (0.06). The relative toxicity index (RTI), which represents the ratio of toxicity due to the difference in sources, increases as the contribution of the highly toxic sources increases. The RTI over 1 is closely associated with an increased contribution from highly toxic sources, such as diesel exhaust, gasoline exhaust and biomass burning. It is necessary to investigate the toxicity of various PM2.5 sources and PM2.5 risk based on the sources.

Air pollution is increasing, along with consumption of fossil fuels such as coal and diesel gas. Air pollutants are known to be a major cause of respiratory-related illness and death, however, there are few reports on the genotoxic characterization of diverse air pollutants in Korea. In this study, we investigated the mutagenic activity of various particles such as diesel exhaust particles (DEP), combustion of rice straw (RSC), pine stem (PSC), and coal (CC), tunnel dust (TD), and road side dust (RD). Ultra-fine particles (UFPs) were collected by the glass fiber filter pad. Then, we performed a chemical analysis to see each of the component features of each particulate matter. The mutagenicity of various UFPs was determined by the Ames test with four Salmonella typhimurium strains with or without metabolic activation. The optimal concentrations of UFPs were selected based on result of a concentration decision test. Moreover, in order to compare relative mutagenicity among UFPs, we selected and tested DEP as mutation reference. DEP, RSC, and PSC induced concentration-dependent increases in revertant colony numbers with TA98, TA100, and TA1537 strains in the absence and presence of metabolic activation. DEP showed the highest specific activity among the particulate matters. In this study, we conclude that DEP, RSC, PSC, and TD displayed varying degrees of mutagenicity, and these results suggest that the mutagenicity of these air pollutants is associated with the presence of polycyclic aromatic hydrocarbons (PAHs) in these particulate matters.

We investigated the influence of substrate surface energy before seed layer formation on hydrothermally grown zinc oxide (ZnO) nanowires (NWs). The qualities of ZnO NWs prepared by the surface-enhanced growth method with ultraviolet ozone (UVO) treatment were analyzed in terms of crystalline morphology and surface defect density, and were compared with those of ZnO NWs prepared by the conventional bulk-enhanced growth method adopting polyethyleneimine (PEI) as the surfactant in an aqueous growth solution. In both cases, a positive effect on the morphological properties and crystallinity of ZnO NWs was observed; however, the surface-enhanced growth method was more efficient for obtaining hydrothermally grown ZnO NWs with higher aspect ratios and larger surface areas. The ZnO NW growth rate in the surface-enhanced growth method was two times faster than in the conventional bulk-enhanced growth method. Photoluminescence (PL) spectra and time-resolved PL (TR-PL) responses indicated that a high density of oxygen vacancies on ZnO NW surfaces was produced by the surface-enhanced growth method, because highly oriented ZnO NWs can be grown without surface passivation effect, on the contrary with the bulk-enhanced growth method.

Regulatory T cells play an important role in autoimmunity and have been shown to exert anti-inflammatory effects in allergic asthma. Mouse model of airway inflammation was used to examine the suppressive activity of luteolin-induced CD4+CD25+ regulatory T cells (Tregs) in vivo. In this study, BALB/c mice were sensitized with ovalbumin antigen (OVA) by aerosol challenge. Then, various biological processes were examined, including airway eosinophilia; mucus hypersecretion; elevation of OVA-specific IgE, expression of Th2 cytokines and chemokine levels; expression of eotaxin 2 and CCR3; and airway hyper responsiveness (AHR). Luteolin significantly inhibited OVA-induced increase in immune cell and eosinophil counts as well as IL-4, IL-5, IL-13, and eotaxin levels in bronchoalveolar lavage fluid (BAL Fluid). Luteolin and cyclosporine A (CsA) which was a positive control also substantially reduced OVA-specific IgE levels, eotaxin 2 levels, and CCR3 expression in BAL Fluid. In contrast, luteolin significantly increased IL-10 and IFN-γ protein levels, as well as IL-10 and TGF-β1 mRNA expression in the lung. In vitro studies showed that the number of luteolin-induced CD4+CD25+ Treg (iTreg) cells was higher, with elevated levels of TGF-β1 and foxp3 mRNA expression in lungs tissue. Transfer of iTreg cells into OVA-sensitized mice reduced AHR, eosinophil recruitment, eotaxin, IgE, and Th2 cytokine expressions, and increased IFN-γ production in BAL Fluid after allergen challenge. Furthermore, adoptive transfer of iTreg cells prevented disease in a CD25-depleted mouse asthma model. Luteolin via induction of foxp3 and CD4+CD25+ Treg cells may represent a new strategy in the development of therapies for managing asthma.

Accumulating epidemiological evidence indicates that exposure to fine air pollution particles (APPs) is associated with a variety of adverse health effects. However, the exact physiochemical properties and biological toxicities of fine APPs are still not well characterized. We collected four types of fine particle (FP) (diesel exhaust particles [DEPs], natural organic combustion [NOC] ash, synthetic organic combustion [SOC] ash, and yellow sand dust [YSD]) and investigated their physicochemical properties and in vitro biological toxicity. DEPs were almost entirely composed of ultrafine particles (UFPs), while the NOC, SOC, and YSD particles were a mixture of UFPs and FPs. The main elements in the DEPs, NOC ash, SOC ash, and YSD were black carbon, silicon, black carbon, and silicon, respectively. DEPs exhibited dose-dependent mutagenicity even at a low dose in Salmonella typhimurium TA 98 and 100 strains in an Ames test for genotoxicity. However, NOC, SOC, and YSD particles did not show any mutagenicity at high doses. The neutral red uptake assay to test cell viability revealed that DEPs showed dose-dependent potent cytotoxicity even at a low concentration. The toxicity of DEPs was relatively higher than that of NOC, SOC, and YSD particles. Therefore, these results indicate that among the four FPs, DEPs showed the highest in vitro biological toxicity. Additional comprehensive research studies such as chemical analysis and in vivo acute and chronic inhalation toxicity tests are necessary to determine and clarify the effects of this air contaminant on human health.

We discuss the effects of surface energy and seed layer annealing temperature (Tannealing) on seed layer growth and hydrothermally-grown zinc oxide (ZnO) nanowires (NWs). In this work, by varying the ultraviolet ozone (UVO) treatment times on a silicon surface, the surface energy conditions for the seed layer formation changed and the seed layer was annealed under different Tannealing conditions. Under a lower surface energy condition of the substrate, with increasing Tannealing, the coverage density and the average thickness of the seed layer increased, but island-like growth was observed. This case was inevitably accompanied by an increase in surface roughness, which resulted in agglomerated low density growth of ZnO NWs. After sufficient UVO treatment, hydroxyl groups on the silicon surface activated the ZnO seed layer formation in the chemical reaction and increased the bonding energy between the active nucleation sites of the seed layer and the substrate surface. This ensured higher coverage density of the seed layer with lower surface roughness under the same Tannealing condition, thereby providing the ZnO NW growth with an enhanced density and aspect ratio as well as good crystallinity.

In this research, we developed a wearable temperature-sensing element by dip dyeing threads in poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) (p-type conducting polymer) solution. The PEDOT:PSS was used to dye the textile and it exhibited negative temperature coefficient characteristics in which the resistance decreases as the temperature increases. The fabricated temperature-detection thread achieved a sensitivity of 167.1 &Omega, /&deg, C with 99.8% linearity in the temperature range of &minus, 50 &deg, C to 80 &deg, C. We anticipate that temperature sensors that apply our technology will be made as stitch- or textile-type for wearable devices, and they will be widely adopted for different applications such as in fitness, leisure, healthcare, medical treatment, infotainment, industry, and military applications, among others.

Herein, the toxicity of particles generated from the complete combustion of 1 g coal at 500, 700, and 900 °C were compared, and combustion at 700 °C generated the most toxins. Chemical analyses revealed that all components except catechol, resorcinol, and aromatic amines were most abundant at 700 °C. Toxicity results confirmed that the relative mutagenicity, cytotoxicity, redox cycling, and production of reactive oxygen species was highest for particles generated at 700 °C. Particles generated during combustion at 700 °C exhibited higher toxicity toward biological systems due to a higher content of toxic compounds.

Fine particulate matters less than 2.5 µm (PM2.5) in the ambient atmosphere are strongly associated with adverse health effects. However, it is unlikely that all fine particles are equally toxic in view of their different sizes and chemical components. Toxicity of fine particles produced from various combustion sources (diesel engine, gasoline engine, biomass burning (rice straw and pine stem burning), and coal combustion) and non-combustion sources (road dust including sea spray aerosols, ammonium sulfate, ammonium nitrate, and secondary organic aerosols (SOA)), which are known major sources of PM2.5, was determined. Multiple biological and chemical endpoints were integrated for various source-specific aerosols to derive toxicity scores for particles originating from different sources. The highest toxicity score was obtained for diesel engine exhaust particles, followed by gasoline engine exhaust particles, biomass burning particles, coal combustion particles, and road dust, suggesting that traffic plays the most critical role in enhancing the toxic effects of fine particles. The toxicity ranking of fine particles produced from various sources can be used to better understand the adverse health effects caused by different fine particle types in the ambient atmosphere, and to provide practical management of fine particles beyond what can be achieved only using PM mass which is the current regulation standard.

We propose a design for a highly sensitive volatile organic compounds (VOCs) sensor based on evanescent wave coupling of a side-polished optical fiber. The surface of the side-polished optical fiber coupled with a coated solvatochromic dye has charge-transfer (CT) properties. In the proposed model, the application of these optical properties and the novel solvatochromic dye helped overcome problems caused by limited sensitivity, selectivity, and dynamic range that are encountered in typical gas sensors. The different polarities of the VOCs cause changes in the effective refractive index of the sensing membrane owing to CT properties. This can lead to a change in the resonance wavelength of the side-polished optical fiber. To ascertain the effectiveness of the sensor, five VOCs dimethylamine, acetic acid, toluene, benzene, and ethanol were tested, and the enhance in sensitivity was analyzed for varying concentrations. According to the results, the proposed gas sensor showed high sensitivity and resolution.

This paper presents the inkjet-printed flexible temperature and humidity sensor(F-TH sensor) using PEDOT:PSS. The series, meshand parallel type sensing element using PEDOT:PSS ink was printed on the overhead projector(OHP) film. The fabricated sensor ofeach structure has the temperature sensitivity of 140 Ω/ o C, 29 Ω/ o C and 1.4 Ω/ o C with linearity, respectively. Also the fabricated sensorwas not only possible to measure a temperature, but also to detect humidity. The humidity sensitivity of 400 Ω/%RH, 3.4 Ω/%RH and3 Ω/%RH with linearity, respectively. The fabricated F-TH sensor is expected for the various applications such as electronic devices,bio-healthcare, industrial field.Keywords: Inkjet print, Flexible sensor, Temperature sensing, Humidity sensing 1. 서론 최근 유연한 전자기기에 대한 관심이 높아지고 있으며, 이애 따라 유연성 기판의 사용이 용이한 인쇄 전자 산업 및 인쇄 전자 기술에 대한 관심도 함께 높아지고 있다[1-6]. 잉크젯 프린팅은 비접촉식 프린팅 기술로써 노즐로부터 액적(drop)을 분사하여 기판위에 패턴을 직접 인쇄하는 기술이다. 기존의 포토리소그래피 기술과 비교하였을 때 빠른 패턴 제작이 가능하고, 공정과정이 줄어시간과 공정비용을 절감할 수 있으며, 재료의 낭비가 적어 전자기기, 의료·바이오, 산업 분야 등에서 유용한 기술이다. 현재 잉크젯 프린팅 공정을 이용하여 인쇄 전자 소자 제작 및 유연성 회로,디스플레이, 센서, 배터리 등의 인쇄 전자 기기에 적용하기 위한연구가 많이 진행되고 있다[7,8]. 잉크젯 프린팅 기술은 대부분 전도성 잉크를 이용하여 프린트회로기판(PCB), RFID, 전극 및 배선등의 소자분야에 적용[9-12]뿐만 아니라, LCD 칼라필터 공정 등에 적용되고 있다[13]. 이러한 잉크젯 프린팅 기술로 제작하는 센서의 경우 가볍고, 공정이 간단하며, 저렴한 공정비용, 유연성 기판 적용이 가능하고, 상온 공정 등의 장점이 있어 유연성 전자기기의 구동 소자로서 각광받고 있다. 잉크젯 프린팅 기술을 이용한유연성 센서의 개발은 경량화, 간편화, 휴대성 등의 강점을 가지고 있어서 유비쿼터스 시대에 활용하기 위한 유용한 소자이다. 본 연구에서는 유연한 기판 위에 유기태양전지에 주로 사용되는 P형 전도성 고분자 물질인 PEDOT:PSS 잉크를 이용하여,잉크젯 프린팅 기법으로 유연성 온·습도 감지 소자를 개발하고, 구조 별 소자의 특성을 비교했다.

Regulatory T cells play an important role in autoimmunity and have been shown to exert anti-inflammatory effects in allergic asthma. Mouse model of airway inflammation was used to examine the suppressive activity of luteolin-induced CD4

Accumulating epidemiological evidence indicates that exposure to fine air pollution particles (APPs) is associated with a variety of adverse health effects. However, the exact physiochemical properties and biological toxicities of fine APPs are still not well characterized. We collected four types of fine particle (FP) (diesel exhaust particles [DEPs], natural organic combustion [NOC] ash, synthetic organic combustion [SOC] ash, and yellow sand dust [YSD]) and investigated their physicochemical properties and in vitro biological toxicity. DEPs were almost entirely composed of ultrafine particles (UFPs), while the NOC, SOC, and YSD particles were a mixture of UFPs and FPs. The main elements in the DEPs, NOC ash, SOC ash, and YSD were black carbon, silicon, black carbon, and silicon, respectively. DEPs exhibited dose-dependent mutagenicity even at a low dose in Salmonella typhimurium TA 98 and 100 strains in an Ames test for genotoxicity. However, NOC, SOC, and YSD particles did not show any mutagenicity at high doses. The neutral red uptake assay to test cell viability revealed that DEPs showed dose-dependent potent cytotoxicity even at a low concentration. The toxicity of DEPs was relatively higher than that of NOC, SOC, and YSD particles. Therefore, these results indicate that among the four FPs, DEPs showed the highest in vitro biological toxicity. Additional comprehensive research studies such as chemical analysis and in vivo acute and chronic inhalation toxicity tests are necessary to determine and clarify the effects of this air contaminant on human health.

We have studied the lifetime improvement of organic solar cells (OSCs) based on the conjugated polymer:fullerene blends using an ultra-violet (UV) blocking transparent conducting oxide (TCO). Without additional passivation films/layers or changing of structure, the performance of the OSC using UV blocking TCO was comparatively stable under the strong UV exposure. When 30 mW/cm2 of UV was irradiated for 300 seconds, the VOC and FF of the OSC without UV blocking TCO decreased to 87% and 64%, respectively. As a result, power conversion efficiency (PCE) decreased to 54%. However, the VOC and FF of OSC with UV blocking TCO slightly decreased to 96% and 87%, respectively.

Background The roots of Korean red ginseng (Panax ginseng C.A.Mey.; KGC) have been used as an herbal supplement to enhance vital energy and immune capacity. Salvia plebeia R.Br. has been used to treat inflammatory diseases. Purpose The aim of this study was to examine the anti-asthmatic effects of a mixture of Korean red ginseng and Salvia plebeia R.Br. (KGC3P), its component nepetin, and their modes of action in alleviating ovalbumin (OVA)-induced asthma in mice. Method BALB/c mice were sensitized with OVA then subjected to intratracheal, intraperitoneal, and aerosol challenges. KGC3P and nepetin were administered orally for four weeks. Airway hyperresponsiveness (AHR), OVA-specific IgE levels, and Th2 cytokine- and gene expression levels in bronchoalveolar lavage fluid (BALF) and splenocytes were measured. Histological and immune cell subtype analyses were performed. PTEN and Akt phosphorylation levels were also evaluated. Results KGC3P reduced OVA-induced AHR, serum IgE levels, histological changes, and eosinophils infiltration but also the absolute number of immune cell subtypes including CD3+/CD4+, CD3+/CD8+, CD4+/CD69+, and Gr-1+/CD11b+ in the lungs, BALF, and mesenteric lymph nodes (MLN). KGC3P also lowered the Th2 cytokines IL-4, IL-5, and IL-13 in the BALF and splenocytes and downregulated the IL-4, IL-13, IL-17, TNF-α, and MUC5AC genes in the lung. KGC3P upregulated the peroxisome proliferator-activated receptor (PPAR)γ gene but downregulated the p-Akt and p-PTEN phosphorylation. Similar results were obtained with nepetin treatment. Conclusion KGC3P and nepetin are anti-asthmatic because they reduce various immune cells such as eosinophils and Th2 cell as well as Th2 cytokines. These mechanisms may be accompanied by the regulation of PPARγ expression and the PTEN pathway. Taken together, our results indicate that KGC3P and nepetin may potentially prevent and treat asthma.

For improving the thermal conductivity of carbon nanotube-epoxy composite, we have performed the chemical surface pre-treatment of multi-walled carbon nanotube (MWCNT) and investigated its effects. In the experiments, the mixtures of nitric and sulfuric acid have been used as the surface modifier for MWCNT. The chemical surface pre-treatments by acid mixtures lead to the production of oxygen-containing functional groups on the surfaces of MWCNT. Also, the surface area and pore volume of acid-treated MWCNT (AT-MWCNT) become larger than those of pristine MWCNT. By actions of the chemical pre-treatment, AT-MWCNT is well dispersed and forms the heat flow network in epoxy matrix, resulting in higher thermal conductivity of carbon nanotube-epoxy composite.

For the application to transparent electrode in flexible dye-sensitized solar cells (DSSCs), Zn-doped In2O3 (In2O3:Zn) thin films have been fabricated on polyethylene naphthalate (PEN) substrate by the radio frequency facing target sputtering method, and their characteristics have been investigated as a function of deposition pressure. X-ray diffraction study reveal that the structure of In2O3:Zn thin films is amorphous nature. The film morphology is slightly sensitive to the deposition pressure. At the sputtering pressure of 0.40 Pa, In2O3:Zn thin film on PEN exhibits a sheet resistance of about 12.4 Ω/□ and average transmittance of about 85% at 550 nm wavelength, resulting in the highest value for figure of merit. The flexible DSSC device with the In2O3:Zn electrode shows the efficient solar-to-electrical power conversion efficiency (η), which is the maximum η value of 4.6% under simulated air mass 1.5 irradiation (100 mW/cm2).

In this study, we have investigated the effect of panaxatriol (PT) on phosphoinositides (PIS) breakdown and Ca 2+ -elevation in thrombin-induced platelet aggregation. Thrombin (5U/ml), a potent platelet agonist which activates phospholipase C β via protease activated receptor (PAR), hydrolyzed PIS in platelet membrane. The phosphatidylinositol 4, 5-bisphosphate (PIP₂) was hydrolyzed after 10 sec of the thrombin-stimulation, and both the phosphatidylinositol 4-monophosphate (PIP) and phosphatidylinositol (PI) were brokendown after 30 sec of the thrombin-stimulation. However, PT inhibited the thrombin-stimulated hydrolysis of PIP₂, PIP, and PI. On the other hand, thrombin increased the level of phosphatidic acid (PA) which is phosphorylated from diacylglycerol (DG) generated by PIS-hydrolysis. However, PT inhibited the thrombin-increased PA level non-significantly. Thrombin increased cytosolic free Ca 2+ [Ca 2+ ] i ) up to 72% as compared with control (30.8±0.9 nM) in intact platelet. However, PT (100 ㎍/ml) inhibited the thrombin-elevated [Ca 2+ ] i to 100%. These results suggest that PT may have a beneficial effect on platelet aggregation-mediated thrombotic disease by inhibiting thrombin-induced platelet aggregation via suppression of the [Ca 2+ ] i level and PIS breakdown.

Low power bridge type micro gas sensors were fabricated by micro machining technology with TMAH (Tetra Methyl Ammonium Hydroxide) solution. The sensing devices with different heater materials such as metal and poly-silicon were obtained using CMOS (Complementary Metal Oxide Semiconductor) compatible process. The tellurium films as a sensing layer were deposited on the micro machined substrate using shadow silicon mask. The low power micro gas sensors showed high sensitivity to NO with high speed. The pure tellurium film used micro gas sensor showed good sensitivity than transition metal (Pt, Ti) used tellurium film.

The characteristic of tellurium thin films was studied for detecting nitrogen dioxide gas at room temperature. The film was deposited on substrate by using thermal evaporator. The subsequent process was heat treatment by several conditions. (temperature, flowed gases) Surface and grain boundary was investigated using SEM. The results showed that resistance of the tellurium film decreases reversibly in the presence of nitrogen dioxide. The sensitivity of this device depends on the gas concentration and detect lower concentrations less than 10 ppm.

We presented improved density and aspect ratio of ZnO nanowires which were hydrothermally grown on spin coated ZnO seed layer. After UVO treatment on silicon surface, spin coated ZnO seed layer showed a high coverage density due to increased surface wettability without forming island like growth in conventional method. ZnO active nucleation sites showed a positive increasing relation with increase in coverage density. Whereas, increased spin coating time had risen surface roughness with rise in coverage area, UVO treated surface wettability change had showed lower surface roughness. Moreover, seed layer thickness remained unaffected for surface wettability changing effect. This let ZnO nanowires grow on the increased ZnO active nucleation sites without hindrance of other nanowires. Hence, higher density and aspect ratio ZnO nanowires were achieved by controlling surface wettability via UVO treatment.

Macrophages activated by microbial lipopolysaccharides (LPS) produce bursts of nitric oxide and reactive oxygen species (ROS). Redox protection systems are essential for the survival of the macrophages since the nitric oxide and ROS can be toxic to them as well as to pathogens. Using suppression subtractive hybridization (SSH) we found that cytosolic NADP(+)-dependent isocitrate dehydrogenase (IDPc) is strongly upregulated by nitric oxide in macrophages. The levels of IDPc mRNA and of the corresponding enzymatic activity were markedly increased by treatment of RAW264.7 cells or peritoneal macrophages with LPS or SNAP (a nitric oxide donor). Over-expression of IDPc reduced intracellular peroxide levels and enhanced the survival of H2O2- and SNAP-treated RAW264.7 macrophages. IDPc is known to generate NADPH, a cellular reducing agent, via oxidative decarboxylation of isocitrate. The expression of enzymes implicated in redox protection, superoxide dismutase (SOD) and catalase, was relatively unaffected by LPS and SNAP. We propose that the induction of IDPc is one of the main self-protection mechanisms of macrophages against LPS-induced oxidative stress.

We have studied the effects of ginsenoside Rb1 (GRb1) on the change in lipid contents in rat liver. When GRb1 was administered intraperitoneally to rats, liver microsomal cytochrome P-450 content and NADPH-cytochrome P-450 reductase activity were lower than those in control rats. The contents of triglyceride (TG) and cholesterol were decreased, but those of total phospholipid, phosphatidylcholine, and phosphatidylethanolamine were increased in the GRb1-treated group compared with controls. These results indicate that GRb1 might be involved in lipid metabolism by regulating the activity of microsomal cytochrome P-450 monooxygenase. Although liver TG levels were reduced by GRb1, the levels of TG and beta-lipoprotein in serum from the GRb1-treated group did not change as compared with those in controls. Thus we suggest that the decrease in liver TG levels with GRb1-treatment is not associated with the secretion of TG-rich very low-density lipoprotein. Furthermore, the level of cAMP was also significantly increased in the GRb1-treated group as compared with that in controls. Additionally, the cAMP level was more markedly increased as compared with that in the GRb1-treated group or control group when GRb, was exogenously added to the reaction system for measuring cAMP production in homogenates from control group liver. Accordingly, these results demonstrate that GRb1 might lower TG levels via cAMP-production in the liver, and GRb1 might be an interesting candidate to for a modulator of cAMP-mediated effects, especially within the liver steatosis system.

The effects of an acidic polysaccharide isolated from the ethanol-insoluble and water-soluble fraction of Panax ginseng C. A. Meyer on immunomodulating activities were investigated. A high output nitric oxide synthase (iNOS) was shown in female BALB/c mice administered intraperitoneally with the acidic polysaccharide from ginseng. Newly synthesized iNOS protein was also observed in peritoneal macrophages cultured with interferon-gamma and the acidic polysaccharide. Spleen cells from acidic polysaccharide-treated mice did not proliferate in response to concanavalin A, but restored the responsiveness by the cotreatment of NG-monomethyl-L-arginine (NMMA) with concanavalin A. The treatment of mice with aminoguanidine, a specific iNOS inhibitor, alleviated the acidic polysaccharide-induced suppression of antibody response to sheep red blood cells. Present results suggest that the immunomodulating activities of the acidic polysaccharide were mediated by the production of nitric oxide.

TLR4 together with CD14 and MD-2 forms a pattern recognition receptor that plays an initiating role in the innate immune response to Gram-negative bacteria. Here, we employed the surface plasmon resonance technique to investigate the kinetics of binding of LPS to recombinant CD14, MD-2 and TLR4 proteins produced in insect cells. The dissociation constants (KD) of LPS for immobilized CD14 and MD-2 were 8.7 microM, and 2.3 microM, respectively. The association rate constant (Kon) of LPS for MD-2 was 5.61 x 10(3) M-1S-1, and the dissociation rate constant (Koff) was 1.28 10 2 S 1, revealing slow association and fast dissociation with an affinity constant KD of 2.33 x 10-6 M at 25 degreesC. These affinities are consistent with the current view that CD14 conveys LPS to the TLR4/MD-2 complex.

We have recently reported that red ginseng acidic polysaccharide (RGAP), isolated from Korean red ginseng (Panax ginseng C.A. Meyer), shows immunomodulatory and antitumor activities, mainly mediated by the nitric oxide (NO) production of macrophages. This compound may be used in cancer therapy alone or in combination with other chemotherapeutic agents. The synergistic effect of RGAP and paclitaxel (taxol) was evaluated to develop new biological response modifiers in cancer therapy. The present study demonstrates a synergistic antitumor effect of RGAP and paclitaxel in mice transplanted with sarcoma 180 and B16 melanoma. Combined treatment with paclitaxel (5 or 15 mg/kg) and RGAP (25 mg/kg) resulted in a 28.6 or 42.8 % increase in the life span of ICR mice bearing sarcoma 180 tumor cells, while no obvious effect was seen on sole paclitaxel treatment. When a combination of paclitaxel (10 mg/kg) and RGAP (100 mg/kg) was administered to C57BL/6 mice implanted with B16 melanoma, the tumor weight per mouse also decreased by 76.3 %, suggesting that RGAP may be used as an adjuvant in medicinal applications of paclitaxel. The augmented antitumor effect of paclitaxel is supposed to be the result of the immunomodulating antitumor effect of RGAP. RGAP, having B cell specific mitogenic activity, induced the secretion of interleukin-6 (IL-6) in spleen cells in a concentration-dependent manner (5 to 500 microg/microL). RGAP also restored the proliferation of splenocytes and NK cell activity suppressed by paclitaxel. Flow cytometric analysis of splenocytes in mice treated with paclitaxel showed a significant increase of CD11b+ cells. Additionally, a synergistic effect of RGAP and paclitaxel was found to effect an increased tumoricidal activity of macrophages. The above results suggest that clinical trials of RGAP as an adjuvant in cancer chemotherapy of paclitaxel are highly feasible.