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101.
Mechanisms by which Wnt pathways integrate the organization of receptors, organelles, and cytoskeletal proteins to confer cell polarity and directional cell movement are incompletely understood. We show that acute responses to Wnt5a involve recruitment of actin, myosin IIB, Frizzled 3, and melanoma cell adhesion molecule into an intracellular structure in a melanoma cell line. In the presence of a chemokine gradient, this Wnt-mediated receptor-actin-myosin polarity (W-RAMP) structure accumulates asymmetrically at the cell periphery, where it triggers membrane contractility and nuclear movement in the direction of membrane retraction. The process requires endosome trafficking, is associated with multivesicular bodies, and is regulated by Wnt5a through the small guanosine triphosphatases Rab4 and RhoB. Thus, cell-autonomous mechanisms allow Wnt5a to control cell orientation, polarity, and directional movement in response to positional cues from chemokine gradients. 相似文献
102.
Curcumin dye in methanol solution was treated in 100°C oven (OV) and H2O2/UV/O2 (PER) conditions and the degradation products were examined using gas chromatography mass spectrometry (GC-MS). Curcumin
itself was not detected from either the OV or PER degraded samples. From OV degradation samples curcumene1, o-coumaric acid2, vanillin3, 2,4-di-tert-butylphenol4, benzene, 1-(3-cyclopentylpropyl)-2,4-dimethyl-45, 1-(4-hydroxy-benzylidene) acetone6, feruloylmethane7, and 2-propenoic acid, 3-[4-(acetyloxy)-3-methoxy phenyl]-, methyl ester8 were detected. From PER degraded samples new products benzoic acid9 and vanillic acid10 were detected additionally. Under the same GC-MS instrumental condition, it is possible that the burial degraded curcumin
dye or curcumin dyed textile will exhibit area peaks around 6.2∼6.5 min and 8.3∼8.4 min retention times, which have the mass
spectrum matching closely with products3, 4, 7, 8 or9, 10. 相似文献
103.
Cheunsoon Ahn Hye-Ja Yoo Hye Ja Lee Jung Hee Kim Kyung-Hun Song Jeon Sook Rhie 《Fibers and Polymers》2005,6(1):28-34
The purpose of the research was to examine the effect of three different levels of enzyme treatment on the physical characteristics
and the end-use suitability of the lyocell fabrics made with four different types of commercial wood pulp. The appropriate
enzyme concentration for obtaining an optimum as well as consistent physical characteristics and fabric hand trait was 3 g/l for the concentration levels tested in the present investigation. Weight loss was more affected by higher enzyme concentration
than other physical properties. H2 was least affected by enzyme treatment for all three physical properties and fabric hand.
5 g/l concentration exhibited little difference from 3 g/l in the physical characteristics, whereas the KES-FB values indicated a significant loss of fabric hand in most PHVs with
the 5 g/l concentration level. Among different garment parameters, all four fabric types were relatively inappropriate for the men’s
slacks (MS) fabric due to the lower hand value of koshi required by the MS parameter. However, despite the relatively low
koshi values, high fukurami values required for men’s dress shirt (MWDS) resulted in the highest THV among the four garment
parmeters. The four fabric types, which represent the usage of four different wood pulps, in general seem to exhibit a higher
applicability to women’s winter thin dress (WWTD) than women’s winter suit (WWS) garment parameter. 相似文献
104.
Seung Jae Ahn Moo Sung Lee Dae Young Lim Jung Nam Im Seung Goo Lee Ji Ho Youk Han-Yong Jeon 《Fibers and Polymers》2013,14(12):2191-2196
The permeability defined by Darcy’s law indicates the degree of ability that a fluid can flow through nonwoven media under a differential pressure in laminar flow. The permeability generally indicates the specific permeability or absolute permeability. On the other hand, if the fluid is water, the permeability indicates the hydraulic conductivity or permeability coefficient. The permeability is one of the important properties for nonwoven media and a prediction of the permeability acts as a bridge between the manufacturing technology and performance requirements. Because capillary channel theory aims to make the flow of fluid easier and more understandable, many models are based on capillary channel theory. On the other hand, the theory has a limitation in that it is unsuitable for high porosity media. In this study, a very thin downstream layer, which was suggested by Lifshutz [9], was introduced to derive a prediction model of hydraulic permeability. Needle-punched and spunbonded nonwoven fabrics with various basis weights were used in the cross-plain water permeability test. From this ‘thin layer’ model, reasonable agreement between the predicted and experimental results was obtained. 相似文献
105.
106.
Toxic solvent and strong acid catalysts causing environmental issues have been mainly used for ring-opening of epoxidized oleochemicals. Here, we demonstrated that magnesium stearate (Mg-stearate) was a high efficient catalyst for solvent-free ring-opening of epoxidized methyl oleate, a model compound of midchain epoxide. Mg-stearate resulted in the highest yield (95%) and conversion rate (99%) toward midchain alkoxyesters under the same conditions (160 °C, 12 h) superior to other fatty acid derivatives such as a Lewis acid (lithium and sodium stearate) and Br?nsted acid (stearic acid). Based on this chemical study, we synthesized biogrease and thermoplastic using epoxidized soybean oil (ESO) and Mg-stearate via one-pot, solvent-free, and purification-free process. Mg-stearate played a significant role as a reactant for epoxide ring-opening and as a thickener when excess loading rate was used; viscosity increased from 1800 to 4500 Pa·s at 25 °C when ESO:Mg-stearate increased from 1:1 equiv to 1:2, then behaved like thermoplastics (T(g) = -27 °C, T(m) = 90 °C) with 1:4. 相似文献
107.
McCoy MR Yang Z Fu X Ahn KC Gee SJ Bom DC Zhong P Chang D Hammock BD 《Journal of agricultural and food chemistry》2012,60(20):5065-5070
Pyrethroids are a class of insecticides that are becoming increasingly popular in agricultural and home use applications. Sensitive assays for pyrethroid insecticides in complex matrices are difficult with both instrumental and immunochemical methods. Environmental analysis of the pyrethroids by immunoassay requires either knowing which pyrethroids contaminate the source or the use of nonspecific antibodies with cross-reactivities to a class of compounds. We describe an alternative method that converts the type II pyrethroids to a common chemical product, 3-phenoxybenzoic acid (3-PBA), prior to analysis. This method is much more sensitive than detecting the parent compound, and it is much easier to detect a single compound rather than an entire class of compounds. This is useful in screening for pyrethroids as a class or in situations where a single type of pyrethroid is used. We demonstrated this technique in both citrus oils and environmental water samples with conversion rates of the pyrethroid to 3-PBA that range from 45 to 75% and methods that require no extraction steps for either the immunoassay or the liquid chromatography-tandem mass spectrometry (LC-MS/MS) techniques. Limits of detection for this technique applied to orange oil are 5 nM, 2 μM, and 0.8 μM when detected by LC-MS/MS, gas chromatography-mass spectrometry, and immunoassay, respectively. The limit of detection for pyrethroids in water when detected by immunoassay was 2 nM. 相似文献
108.
109.
This study presents a meta-analysis of studies that investigate the effectiveness of chitosan administration on lifestyle-related disease in murine models. A total of 34 published studies were used to evaluate the effect of chitosan supplementation. The effect sizes for various items after chitosan administration were evaluated using the standardized mean difference. Using Cochran’s Q test, the heterogeneity of effect sizes was assessed, after which a meta-ANOVA and -regression test was conducted to explain the heterogeneity of effect sizes using the mixed-effect model. Publication bias was performed using Egger’s linear regression test. Among the items evaluated, blood triglyceride and HDL-cholesterol showed the highest heterogeneity, respectively. Other than blood HDL-cholesterol, total cholesterol, and triglyceride in feces, most items evaluated showed a negative effect size with high significance in the fixed- and random-effect model (p < 0.0001). In the meta-ANOVA and -regression test, administering chitosan and resistant starch was revealed to be most effective in lowering body weight. In addition, chitosan supplementation proved to be an effective solution for serum TNF-α inhibition. In conclusion, chitosan has been shown to be somewhat useful in improving symptoms of lifestyle-related disease. Although there are some limitations in the results of this meta-analysis due to the limited number of animal experiments conducted, chitosan administration nevertheless shows promise in reducing the risk of cholesterol related metabolic disorder. 相似文献
110.
Since the oxidation of low-density lipoprotein (LDL) is one of the main causes of atherosclerosis, Cu2+-induced LDL oxidation and conjugated diene formation is currently being explored for the development of pharmaceutical drugs or functional foods for the treatment of atherosclerosis. The present work investigated the inhibitory effects on in vitro Cu2+-induced human LDL oxidation and conjugated diene formation of the methanol (MeOH) extract of the edible brown alga (Ecklonia stolonifera) and its different solvent-soluble fractions, as well as the phlorotannins isolated from them. The most active ethyl acetate fraction was selected for chromatographic separation to isolate six phlorotannins: phloroglucinol (1), dioxinodehydroeckol (2), eckol (3), phlorofucofuroeckol A (4), dieckol (5), and 7-phloroeckol (6). Compounds 3?C6 showed potent inhibitory activity against Cu2+-induced LDL oxidation as compared with probucol, a well-known clinical therapeutic agent for hypercholesterolemia. Moreover, when compound 5 (at levels of 9 and 4.5???M) was used in combination with probucol (4.5???M), they additively inhibited Cu2+-induced LDL oxidation. In addition, 3?C5 significantly prolonged the lag time of conjugated diene formation at 10???M. These results suggest that the potent antiatherosclerotic effects of E. stolonifera and its isolated phlorotannins may be partly attributed to the inhibition of Cu2+-induced LDL oxidation and conjugated diene formation. 相似文献