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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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1. 1. The objective of this paper is to investigate the indoor environment from the viewpoint of interaction between physical environment and the human responses. The field survey has been conducted over 1 year.

2. 2. A continuous measurement has been carried out for 1 week and distribution of variables have been measured for 1 day.

3. 3. The attitude of workers was investigated by a questionnaire.

4. 4. As the result, average luminance represented more than 1000 lx in the new building, in contrast with less tha 300 lx in the existing building.

5. 5. There was a significant difference of the occupants' response to the light environment between the two buildings.

6. 6. Measured thermal conditions are on the edge of the ASHRAE comfort envelope in summer, and in the neighborhood of the lower dry limit of the envelope in spring.

7. 7. The occupants' evaluations were remarkably changed before and after the moving. The office environment is better than that of the factory.

Author Keywords: Office; post occupancy evaluation; physical environmental condition; occupants' evaluation  相似文献   

4.
A series of naphthoquinones based on the naphtho[2,3-b]furan-4,9-dione skeleton such as (−)-5-hydroxy-2-(1′-hydoxyethyl)naphtho[2,3-b]furan-4,9-dione (1) and its positional isomer, (−)-8-hydroxy-2-(1′-hydoxyethyl)naphtho[2,3-b]furan-4,9-dione (2), which are secondary metabolites found in the inner bark of Tabebuia avellanedae, were stereoselectively synthesized and their biological activities were evaluated in conjunction with those of their corresponding enantiomers. Compound 1 exhibited potent antiproliferative effect against several human tumor cell lines, but its effect against some human normal cell lines was much lower than that of mitomycin. On the other hand, its enantiomer (R)-1 was less active toward the above tumor cell lines than 1. The antiproliferative effect of 2 against all tumor cell lines was significantly reduced. These results indicated the presence of the phenolic hydroxy group at C-5 is of great important for increasing antiproliferative effect. In addition, 1 also showed higher cancer chemopreventive activity than 2, while there were no significant differences between 1 and 2 in antimicrobial activity. Both compounds displayed modest antifungal and antibacterial activity (Gram-positive bacteria), whereas they were inactive against Gram-negative bacteria.  相似文献   
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Based on 2-(4-phenoxybenzoyl)-5-hydroxyindole (2), a novel structural class of CaMKII inhibitors were synthesized and further optimized. The strong acidity of the hydroxyl group and the lipophilic group at the 4 and 6-positions were found to be necessary for strong CaMKII inhibition. Compound 25 was identified as a promising compound with 50-fold more potent inhibitory activity for CaMKII than 2. Compound 25 also showed high selectivity for CaMKII over off-target kinases.  相似文献   
7.
To estimate the water status of Hinoki cypress (Chamaecyparis obtusa) under reduced hydraulic conductance, we measured diurnal changes in the trunk diameter of two 20-year-old trees during a hot dry summer. One tree showed a greatly reduced water-transport area in its trunk cross-section and leaf specific hydraulic conductivity. Diurnal changes in trunk diameter were measured at the xylem surface using a strain-gauge method. At the start of the experiment, the diurnal changes in trunk diameter were similar in both trees with shrinking during the day and swelling at night. However, in the trunk of the tree with reduced hydraulic conductance, the maxima and minima decreased rapidly as days passed. These differences in trunk diameter changes might be caused by the differences in the leaf-specific hydraulic conductance.  相似文献   
8.
Stereochemical properties of the glycosidic linkage have been studied by the quantum-chemical PCILO method, using 2-methoxytetrahydropyran as a model. Calculations of the two-dimensional, conformational (Φ, Ψ) maps showed that the rotation around the C-1---O-1 bond is more hindered than that around the O-1---C-6 bond, and that there are differences in the shape of the energy curve for the axial and equatorial forms of 2-methoxytetrahydropyran. The observed population of the five stable conformers at equilibrium (GG:GT:TG1:TG2:TT = 70.8:6.0:19.9:2.0:1.3) is consistent with the prediction of the anomeric and exo-anomeric effects. The calculated abundance (76.8%) of the axial form of 2-methoxytetrahydropyran is comparable with experimental results (77–80%) obtained by n.m.r. measurements in non-polar solvents. The energies found for individual conformers made it possible to calculate the magnitude of the anomeric effect (3 kJ/mol) and to determine, for the first time, the values of the exo-anomeric effect for axial (6 kJ/mol) and equatorial 2-methoxytetrahydropyran (7 kJ/mol). The calculated variations of the geometry arising from rotation around the C-1---O-1 bond are consistent with results obtained by statistical analysis of experimental data for - and β-glycosides. The results obtained, indicating that the energy, geometry, and electronic structure of glycosides are largely affected by the conformation of the acetal segment, are discussed from the point of view of conformational analysis of oligo- and poly-saccharides.  相似文献   
9.
Rational design by the MO calculation disclosed 5,6-dihydrovaltrate (2) as the bioisostere of valtrate (1), the Rev-export inhibitor with anti-HIV activity. The synthesis of 2 was accomplished by ingenious use of asymmetric Diels–Alder reaction and stereoselective epoxidation associated with the adjacent hydroxyl group. Because of similar biological potency to 1, the analog 2 should be recognized as a promising scaffold for new anti-HIV agents with an unprecedented mechanism of action, inhibition for nuclear export of Rev protein, in the conventional remedy.  相似文献   
10.
Human chorionic gonadotropins (hCGs) highly purified from the urine of patients with trophoblastic diseases and of healthy pregnant women contain approximately four mucin-type sugar chains in one molecule. The structures of these sugar chains were studied comparatively by using a new sensitive method to obtain mucin-type sugar chains quantitatively as radioactive oligosaccharides from a small amount of glycoproteins. The mucin-type sugar chains of all hCGs include sialylated and nonsialylated Gal beta 1----3GalNAc and Gal beta 1----4GlcNAc beta 1----6(Gal beta 1----3)GalNAc. In the case of normal hCG and hydatidiform mole hCG, oligosaccharides containing the tetrasaccharide core occupy approximately 10% of the total mucin-type sugar chains. The ratio of the tetrasaccharide containing oligosaccharides is increased prominently to approximately 60% in choriocarcinoma hCG. The proportion in invasive mole hCG was also increased, but less than the proportion of choriocarcinoma hCG.  相似文献   
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