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121.
Astaxanthin (AST) is a product made from marine organisms that has been used as an anti-cancer supplement. It reduces pontin expression and induces apoptosis in SKBR3, a breast cancer cell line. Using Western blotting and qRT-PCR analyses, this study revealed that in the T47D and BT20 breast cancer cell lines, AST inhibits expression of pontin and mutp53, as well as the Oct4 and Nanog cancer stem cell (CSC) stemness genes. In addition, we explored the mechanism by which AST eradicates breast cancer cells using pontin siRNAs. Pontin knockdown by pontin siRNA reduced proliferation, Oct4 and Nanog expression, colony and spheroid formation, and migration and invasion abilities in breast cancer cells. In addition, reductions in Oct4, Nanog, and mutp53 expression following rottlerin treatment confirmed the role of pontin in these cells. Therefore, pontin may play a central role in the regulation of CSC properties and in cell proliferation following AST treatment. Taken together, these findings demonstrate that AST can repress CSC stemness genes in breast cancer cells, which implies that AST therapy could be used to improve the efficacy of other anti-cancer therapies against breast cancer cells. 相似文献
122.
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
123.
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
124.
Hyeong Rok Yun Sang Woo Ahn Bomin Seol Elena A. Vasileva Natalia P. Mishchenko Sergey A. Fedoreyev Valentin A. Stonik Jin Han Kyung Soo Ko Byoung Doo Rhee Jung Eun Seol Hyoung Kyu Kim 《Marine drugs》2021,19(11)
Atopic dermatitis (AD) is a chronic inflammatory skin disease in which skin barrier dysfunction leads to dryness, pruritus, and erythematous lesions. AD is triggered by immune imbalance and oxidative stress. Echinochrome A (Ech A), a natural pigment isolated from sea urchins, exerts antioxidant and beneficial effects in various inflammatory disease models. In the present study, we tested whether Ech A treatment alleviated AD-like skin lesions. We examined the anti-inflammatory effect of Ech A on 2,4-dinitrochlorobenzene (DNCB)-induced AD-like lesions in an NC/Nga mouse model. AD-like skin symptoms were induced by treatment with 1% DNCB for 1 week and 0.4% DNCB for 5 weeks in NC/Nga mice. The results showed that Ech A alleviated AD clinical symptoms, such as edema, erythema, and dryness. Treatment with Ech A induced the recovery of epidermis skin lesions as observed histologically. Tewameter® and Corneometer® measurements indicated that Ech A treatment reduced transepidermal water loss and improved stratum corneum hydration, respectively. Ech A treatment also inhibited inflammatory-response-induced mast cell infiltration in AD-like skin lesions and suppressed the expression of proinflammatory cytokines, such as interferon-γ, interleukin-4, and interleukin-13. Collectively, these results suggest that Ech A may be beneficial for treating AD owing to its anti-inflammatory effects. 相似文献
125.
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
126.
Information was stored as quantum phase in an N-state Rydberg atom data register. One or more flipped states stored in an eight-state atomic wave packet could be retrieved in a single operation, in agreement with a recent proposal by Grover. 相似文献
127.
Ahn Huijeong Kim Jeongeun Lee Hansae Lee Eunsong Lee Geun-Shik 《Veterinary research communications》2020,44(2):51-59
Veterinary Research Communications - Inflammasome, a cytosolic multi-protein complex, assembly is a response to sensing intracellular pathogenic and endogenic danger signals followed by caspase-1... 相似文献
128.
Hyo-Jin Ahn Hyun Yang Beum-Soo An Kyung-Chul Choi Eui-Bae Jeung 《Journal of veterinary science (Suw?n-si, Korea)》2011,12(4):379-385
Ectonucleotide pyrophosphatase/phosphodiestrase 2 (Enpp2) isolated from the supernatant of human melanoma cells is a lysophospholipase D that transforms lysophosphatidylcholine into lysophospatidic acid. Although multiple analyses have investigated the function of Enpp2 in the hypothalamus, its role in the uterus during the estrous cycle is not well understood. In the present study, rat uterine Enpp2 was analyzed by RT-PCR, Western blotting, and immunohistochemistry. Quantitative PCR analysis demonstrated that uterine Enpp2 mRNA was decreased during estrus compared to proestrus and diestrus. To determine whether uterine Enpp2 expression is affected by sex steroid hormones, immature rats were treated with 17β-estradiol (E2), progesterone, or both on postnatal days 14 to 16. Interestingly, the expression of Enpp2 mRNA and protein were down-regulated by E2 in the uterus during estrus but not during proestrus or diestrus, suggesting that Enpp2 may play a role in uterine function during estrus. Enpp2 is primarily localized in the stromal cells of the endometrium during proestrus and estrus. During diestrus, Enpp2 was highly expressed in the epithelial cells of the endometrium. Taken together, these results suggest that uterine Enpp2 may be regulated by E2 and plays a role in reproductive functions during female rat development. 相似文献
129.
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
130.
Sung-Taek Ahn Sang-Il Suh Hyeongsun Moon Changbaig Hyun 《Canadian journal of veterinary research》2016,80(1):90-92
Growth differentiation factor 11 (GDF11) regulates cell growth and differentiation in both embryonic and adult tissues. Circulating GDF11 levels have recently been reported to be significantly lower in aging mice and restoration of GDF11 reversed age-related cardiac hypertrophy in old mice. Here, we evaluated the potential of serum levels of GDF11 as a circulating biomarker in dogs at different stages of heart failure, due to chronic mitral valve insufficiency (CMVI). We found no significant differences in serum GDF11 levels between dogs at different stages of CMVI-associated heart failure. Furthermore, the circulating levels of GDF11 did not correlate with age, body weight, echocardiographic variables, and the severity of CMVI-induced heart failure in dogs. 相似文献