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1.
Earlier study showed that glucocorticoid induced tumor necrosis factor receptor (GITR), a new TNFR family, activated murine macrophages to express inducible nitric oxide synthase (iNOS) and to generate nitric oxide (NO). A possible involvement of pro-inflammatory cytokines on NO production by GITR was investigated in vitro systems and signaling molecules contributing to sGITR-induced iNOS production are determined in Raw 264.7 cells, a murine macrophage cell line. The result showed that the synergy was afforded by the combination of GITR with IFN-g in a dose-dependent manner but IFN-gamma alone was not able to induce NOS. No effects were observed with TNF-alpha, IL-1beta, or IL-6 co-treated with GITR. To determine signaling molecules contributing to sGITR-induced iNOS production, a specific inhibitor for signal pathway proteins tested showed that PDTC (NF-kappaB) and genistein (tyrosine kinase) inhibited NOS induction significantly, while sodium orthovanadate (tyrosine phosphatase) potentiated NOS expression. These results suggest that activations of NF-kappaB were involved in induction of iNOS by GITR and IFN-gamma priming caused earlier and stronger NF-kappaB activation.  相似文献   
2.
Lim  Hyun-Hee  Choi  Kyeong-Yun  Shin  Ho-Sang 《Chromatographia》2022,85(8):699-717
Chromatographia - Optimal derivatization conditions were established for the simultaneous determination of 12 aliphatic saturated aldehydes, 8 aliphatic saturated ketones, 4 cyclic ketones, 3...  相似文献   
3.
Biophoton emissions from three healthy human subjects were measured for 52 weeks. The active nature of dorsal hands and personal discernable patterns in palmar hands were investigated through frequency count analysis of biophoton emission rates. Also, the seasonal dependency of biophoton emission rates from human hands was studied and we found that emission rates were lowest in autumn. There was a reversion of relative emission rates from the palms and the dorsa depending upon the season. The emission rates from the palms remain rather stable throughout the year, but those from the dorsa vary widely depending upon the season. These features of biophoton emission rates were considered in light of the diagnostic view of traditional Chinese medicine.  相似文献   
4.
This paper deals with the approximate controllability for the semilinear retarded control system. We will also derive the equivalent relation between controllability and stabilizability of the solution for the corresponding linear control system.  相似文献   
5.
Tobacco flavors increase the attractiveness of a tobacco brand and ultimately promote addiction. Information about what flavor and how much flavor is in flavor capsules can provide an effective way to regulate tobacco flavor. In this study, 128 flavor chemicals were identified and quantified by gas chromatography–mass spectrometry using libraries and authentic standards. Validation of the developed method was performed for interference, detection limits, calibration curves, accuracy, and precision. Menthol was the main ingredient in all capsules, and the carcinogenic pulegone was detected. Detected menthofuran, benzyl alcohol, geraniol, and eugenol cause toxic or severe irritation, and detected lactones can increase nicotine addiction by inhibiting nicotine metabolism in smokers. Margin of exposures for carcinogenic pulegone and non-carcinogenic menthol were well below safety thresholds, indicating a significant risk of inhalation exposure. It is desirable to prohibit the use of flavor capsules in consideration of human risk.  相似文献   
6.
A simple method to detect 4-methylimidazole in soft drinks is described. This method is based on headspace solid-phase micro-extraction and gas chromatography–mass spectrometry (HS-SPME GC–MS). The HS-SPME parameters (selection of fiber, extraction temperature, heating time, and pH) were optimized and selected. Under the established condition, the detection and the quantification limit were 1.9 and 6.0 μg L?1 using 4 mL of the liquid sample, respectively. The relative standard deviation for five independent determinations at 100.0 and 500.0 μg L?1 was less than 8 %. The calibration curve was y = 0.6027x–0.0033 with a linearity of r 2 = 0.997. Using the proposed method, the levels of 4-MEI were detected in a range from 94.0 to 324.8 μg L?1. The comparison of liquid chromatography tandem mass spectrometry (LC–MS/MS) with the proposed method was performed and the agreement with LC–MS/MS for all samples was acceptable.  相似文献   
7.
Glucocorticoid-induced TNF receptor (GITR) was a new member of the TNF/nerve growth factor receptor (TNFR/ NGFR) family and induced in murine T cells by dexamathasone. Recombinant soluble GITR (sGITR) induced an inflammation in peritoneal membrane and changes in spleen after i.p. injection of 3 mg/kg in C57BL/6 mice. Spleen was enlarged and percentage of neutrophils and monocytes were increased. The area of red pulp in spleen was increased, while that of white pulp was decreased after GITR injection. The thickening of membrane and neutrophil infiltration was observed in peritoneal membrane with increased myeloperoxidase activity. At later time, neutrophil infiltration moved to inside the tissue with tissue damage. GITR ligand and GITR were expressed constitutively on the surface of spleen cells and cells from peritoneal fluid. In contrast, no significant change in the spleen and in peritoneal membrane was observed in mice treated with LPS. GITR may play a role in body's inflammatory processes.  相似文献   
8.
Single-walled carbon nanotubes (SWCNTs), multiwalled carbon nanotubes (MWCNTs), and oxidized MWCNTs (O-MWCNTs) were studied for the adsorption of ibuprofen (IBU) and triclosan (TCS) as representative types of pharmaceutical and personal care products (PPCPs) under different chemical solution conditions. A good fitting of sorption isotherms was obtained using a Polanyi-Manes model (PMM). IBU and TCS sorption was stronger for SWCNTs than for MWCNTs due to higher specific surface area. The high oxygen content of O-MWCNT further depressed PPCP sorption. The sorption capacity of PPCPs was found to be pH-dependent, and more adsorption was observed at pHs below their pK(a) values. Ionic strength was also found to substantially affect TCS adsorption, with higher adsorption capacity observed for TCS at lower ionic strength. In the presence of a reference aquatic fulvic acid (FA), sorption of IBU and TCS was reduced due to the competitive sorption of FA on carbon nanotubes (CNTs). Sorption isotherm results with SWCNTs, MWCNTs and O-MWCNTs confirmed that the surface chemistry of CNTs, the chemical properties of PPCPs, and aqueous solution chemistry (pH, ionic strength, fulvic acid) all play an important role in PPCP adsorption onto CNTs.  相似文献   
9.
A robotic method has been established for the determination of bromate in sea water and drinking deep-sea water. Bromate in water was converted into volatile derivative, which was measured with headspace solid-phase micro extraction and gas chromatography–mass spectrometry (HS-SPME GC–MS). Derivatization reagent and the HS-SPME parameters (selection of fibre, extraction/derivatization temperature, heating time and; the morality of HCl) were optimized and selected. Under the established conditions, the detection and the quantification limits were 0.016 μg L−1 and 0.051 μg L−1, respectively, and the intra- and inter-day relative standard deviation was less than 7% at concentrations of 1.0 and 10.0 μg L−1. The calibration curve showed good linearity with r2 = 0.9998. The common ions Cl, NO3, SO42−, HPO42−, H2PO4, K+, Na+, NH4+, Ca2+, Mg2+, Ba2+, Mn4+, Mn2+, Fe3+ and Fe2+ did not interfere even when present in 1000-fold excess over the active species. The method was successfully applied to the determination of bromate in sea water and drinking deep-sea water.  相似文献   
10.
2-Methyl pyrazine (2MP) has led to significant interest for its industrial and pharmaceutical uses. The new vapor–liquid equilibria (VLE) at 353.15 K and excess molar volumes (VE) at 298.15 K over the whole mole fraction range for seven binaries (water, n-hexane, cyclohexane, n-heptane, methylcyclopentane (MCP), methylcyclohexane (MCH) and ethyl acetate (EA) with 2MP) have been measured. VLE were measured by using headspace gas chromatography and VE were determined using precision density meter. The water+2MP system has only the minimum boiling azeotrope. The experimental VLE and VE data were well correlated in terms of common gE models and Redlich–Kister equation, respectively.  相似文献   
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