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1.
To explore a novel method using liposomes to suppress macrophages, we screened food constituents through cell culture assays. Curcumin was one of the strongest compounds exhibiting suppressive effects on macrophages. We subsequently tried various methods to prepare liposomal curcumin, and eventually succeeded in preparing liposomes with sufficient amounts of curcumin to suppress macrophages by incorporating a complex of curcumin and bovine serum albumin. The diameter of the resultant nanoparticles, the liposomes containing curcumin, ranged from 60 to 100 nm. Flow cytometric analyses revealed that after intraperitoneal administration of the liposomes containing curcumin into mice, these were incorporated mainly by macrophages positive for F4/80, CD36, and CD11b antigens. Peritoneal cells prepared from mice injected in vivo with the liposomes containing curcumin apparently decreased interleukin-6-producing activities. Major changes in body weight and survival rates in the mice were not observed after administrating the liposomes containing curcumin. These results indicate that the liposomes containing curcumin are safe and useful for the selective suppression of macrophages in vivo in mice.  相似文献   
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Saito  On  Kobayashi  Tatsuya  Hiroi  Maiko  Kawatsu  Masayuki  Takagi  Shun  Nishihiro  Jun  Kagami  Maiko 《Limnology》2019,20(1):21-28
Limnology - Trapa spp. dominate many shallow eutrophic lakes in Japan, which must affect the nutrient dynamics in lakes. Trapa spp. are utilized by several animals, in particular the leaf beetle,...  相似文献   
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Due to the ubiquity of epoxy resin compounds and their potential role in increasing the risk for reproductive dysfunction and cancer, the need for an assessment of human exposure is urgent. Therefore, we developed a method for measuring bisphenol A (BPA) and bisphenol A diglycidyl ether (BADGE) metabolites in human blood samples using high-performance liquid chromatography–electrospray ionization mass spectrometry (LC–MS). Human blood samples were processed using enzymatic deconjugation of the glucuronides followed by a novel sample preparation procedure using a solid-phase-cartridge column. This selective analytical method permits rapid detection of the metabolites, free BPA and a hydrolysis product of BADGE (BADGE-4OH) with detection limits in the low nanogram per milliliter range (0.1 ng ml−1 of BPA and 0.5 ng ml−1 of BADGE-4OH). The sample extraction was achieved by Oasis HLB column on gradient elution. The recoveries of BPA and BADGE-4OH added to human plasma samples were above 70.0% with a standard deviation of less than 5.0%. This selective, sensitive and accurate method will assist in elucidating potential associations between human exposure to epoxy-based compounds and adverse health effects.  相似文献   
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Abstract

Pummerer-type rearrangement of uracil nucleosides having a phenylseleno group in the 2′-, 3′-, and 5′-positions took place upon oxidation with MCPBA in CH2Cl2 followed by treatment with acid anhydrides to yield α-acyloxyselenides.  相似文献   
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Hemin, having two carboxyl groups, was coupled with alpha-(3-aminopropyl)-omega-methoxypoly(oxyethylene) through the acid-amide bond formed with carbodiimide. The modified hemin catalyzed the peroxidase reaction in 1,1,1-trichloroethane using benzoyl peroxide or peroxides in unsaturated fatty acids as the hydrogen acceptor and leuco crystal violet as the hydrogen donor. A basic study on quantitative microanalysis of the lipid peroxides was attempted.  相似文献   
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