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31.
Adhesion molecules such as ICAM-1 are important in the infiltration of leukocytes into the site of inflammation. In this study, we investigated the inhibitory effects of curcumin on ICAM-1 expression and monocyte adhesiveness as well as its underlying action mechanism in the TNF-α-stimulated keratinocytes. Curcumin induced expression of heme oxygenase-1 (HO-1) in the human keratinocyte cell line HaCaT. In addition, curcumin induced Nrf2 activation in dose- and time-dependent manners in the HaCaT cells. Curcumin suppressed TNF-α- induced ICAM-1 expression and subsequent monocyte adhesion, which were reversed by the addition of tin protoporphyrin IX (SnPP), a specific inhibitor of HO-1, or HO-1 knockdown using siRNA. Furthermore, Nrf2 knockdown using siRNA reversed the inhibitory effect of curcumin on the TNF-α-induced ICAM-1 expression and adhesion of monocytes to keratinocytes. These results suggest that curcumin may exert its anti-inflammatory activity by suppressing the TNF-α-induced ICAM-1 expression and subsequent monocyte adhesion via expression of HO-1 in the keratinocytes. [BMB Reports 2013;46(8): 410-415] 相似文献
32.
Ji-Hyuk Park Hwa Jung Kim Geun-Yong Kwon Jin Gwack Young-Joon Park Seung-Ki Youn Jun-Wook Kwon Byung-Guk Yang Moo-Song Lee Miran Jung Hanyi Lee Byung-Yool Jun Hyun-Sul Lim 《PloS one》2016,11(3)
Backgrounds
An outbreak of lung injury among South Korean adults was examined in a hospital-based case-control study, and the suspected cause was exposure to humidifier disinfectant (HD). However, a case-control study with community-dwelling controls was needed to validate the previous study’s findings, and to confirm the exposure-response relationship between HD and lung injury.Methods
Each case of lung injury was matched with four community-dwelling controls, according to age (±3 years), sex, residence, and history of childbirth since 2006 (for women). Environmental risk factors, which included type and use of humidifier and HD, were investigated using a structured questionnaire during August 2011. The exposure to HD was calculated for both cases and controls, and the corresponding risks of lung injury were compared.Results
Among 28 eligible cases, 16 patients agreed to participate, and 60 matched controls were considered eligible for this study. The cases were more likely to have been exposed to HD (odds ratio: 116.1, 95% confidence interval: 6.5–2,063.7). All cases were exposed to HDs containing polyhexamethyleneguanidine phosphate, and the risk of lung injury increased with the cumulative exposure, duration of exposure, and exposure per day.Conclusions
This study revealed a statistically significant exposure-response relationship between HD and lung injury. Therefore, continuous monitoring and stricter evaluation of environmental chemicals’ safety should be conducted. 相似文献33.
随着全球建造业向数字化全面转型,建筑信息模型(BIM)的教学将是未来几年风景园林设计与实施的重要主题。介绍了风景园林专业BIM的教学方法和数字化竖向设计及其应用在BIM场地设计项目中的重要性。数字化竖向设计是实现BIM的途径。风景园林教育必须在其教学中讲解BIM建模方法和过程。 相似文献
34.
35.
Jeyun Jo Heegyu Kim Ji Youn Oh Soyeong Kim Yeong Hye Park Hyeonjin Choi Jee-Yeong Jeong Young-Suk Jung Hwayoung Yun 《Bioorganic & medicinal chemistry letters》2019,29(24):126752
Triple-negative breast cancers (TNBCs) account for approximately 15% of breast cancer cases and exhibit an aggressive clinical behavior. In this study, we designed and synthesized two series of 2-anilinopyrimidines based on the structure of our previously reported compound 1 that act as a selective inhibitor of the basal-like TNBC cell line MDA-MB-468. Through the fine-tuning of 1, cyclic and acyclic amines at 4-position of the pyrimidine core were turned out to be crucial for the selectivity. An extensive analysis of structure-activity relationships of the analogs revealed that aminoalkyl groups at the end of the propyl chain are amenable to modification. Among the newly synthesized analogs, compound 38, bearing 4-chloropiperidinyl and cyclohexyl groups, was found to be the most potent and selective, and was about three times more potent and selective than 1 was against the TNBC cells. 相似文献
36.
Lee Jun-Won Oh Ji Eun Rhee Ki-Jong Yoo Byung-Su Eom Young Woo Park Sang Wook Lee Ji Hyun Son Jung-Woo Youn Young Jin Ahn Min-Soo Ahn Sung-Gyun Kim Jang-Young Lee Seung-Hwan Yoon Junghan 《Molecular and cellular biochemistry》2019,453(1-2):197-203
Molecular and Cellular Biochemistry - Electron transfer occurs through heme-Fe across the cytochrome c protein. The current models of long range electron transfer pathways in proteins include... 相似文献
37.
38.
An in situ calibration of an ultrasound transducer: a potential application for an ultrasonic indentation test of articular cartilage 总被引:5,自引:0,他引:5
A change in mechanical properties of articular cartilage would be considered one of the most reliable signs of cartilage degeneration. While an indentation method has the potential to measure the cartilage properties in vivo, an accurate measurement of cartilage thickness in situ is technically difficult. An ultrasound transducer has often been used to measure the cartilage thickness. However, its accuracy is limited by the lack of an accurate measurement of the ultrasound speed of cartilage, for the ultrasound speed varies according to the pathological conditions of the tissue. Therefore, the objective of this study is to develop an in situ calibration method of predicting the true ultrasound speed of cartilage and thus allow the ultrasound transducer to measure the thickness of the tissue with great accuracy. By simultaneously implementing an indentation testing protocol using the ultrasound transducer as an indenter, this method can also provide an indentation stiffness measurement of cartilage.The feasibility of the proposed method was examined using normal and proteoglycan-depleted cartilage specimens. It was found that the true ultrasound speed measured by the in situ calibration method was sensitive to the proteoglycan depletion (1735+/-35 m/s for normal, and 1598+/-28 m/s for proteoglycan-depleted cartilage), and that the measured cartilage thickness was consistently accurate regardless of the tissue condition. The measured indentation stiffness of articular cartilage was also sensitive to the tissue condition. Thus, this study demonstrates that the proposed ultrasonic indentation technique can be used to accurately identify the abnormality of articular cartilage in situ. 相似文献
39.
Salsolinol (SAL) is a tetrahydroisoquinoline neurotoxin that has been speculated to contribute to pathophysiology of Parkinson's disease and chronic alcoholism. The compound is also found in certain beverages and food stuffs, including soy sauce, beer and bananas. Despite potential human exposure to SAL and its endogenous formation, little is known about the genotoxic or carcinogenic potential of this substance. In the present investigation, SAL induced DNA damage in cultured Chinese hamster lung (CHL) fibroblasts as assessed by single cell gel electrophoresis (Comet). CHL cells treated with SAL also exhibited higher frequencies of chromosomal aberrations than did vehicle-treated controls. Our recent study has revealed that SAL in combination with Cu(II) causes the strand scission in phiX174 supercoiled DNA [Neurosci. Lett. 238 (1997) 95]. In line with this notion, addition of cupric ion potentiated the DNA damaging and clastogenic activity of SAL. Antioxidant vitamins, such as Vitamin C and Vitamin E, and reduced glutathione inhibited clastogenicity of SAL, suggesting the involvement of reactive oxygen species (ROS) in SAL-induced DNA damage and genotoxicity in CHL cells. 相似文献
40.
Park IY Eidsness MK Lin IJ Gebel EB Youn B Harley JL Machonkin TE Frederick RO Markley JL Smith ET Ichiye T Kang C 《Proteins》2004,57(3):618-625
Understanding the structural origins of differences in reduction potentials is crucial to understanding how various electron transfer proteins modulate their reduction potentials and how they evolve for diverse functional roles. Here, the high-resolution structures of several Clostridium pasteurianum rubredoxin (Cp Rd) variants with changes in the vicinity of the redox site are reported in order to increase this understanding. Our crystal structures of [V44L] (at 1.8 A resolution), [V44A] (1.6 A), [V44G] (2.0 A) and [V44A, G45P] (1.5 A) Rd (all in their oxidized states) show that there is a gradual decrease in the distance between Fe and the amide nitrogen of residue 44 upon reduction in the size of the side chain of residue 44; the decrease occurs from leucine to valine, alanine or glycine and is accompanied by a gradual increase in their reduction potentials. Mutation of Cp Rd at position 44 also changes the hydrogen-bond distance between the amide nitrogen of residue 44 and the sulfur of cysteine 42 in a size-dependent manner. Our results suggest that residue 44 is an important determinant of Rd reduction potential in a manner dictated by side-chain size. Along with the electric dipole moment of the 43-44 peptide bond and the 44-42 NH--S type hydrogen bond, a modulation mechanism for solvent accessibility through residue 41 might regulate the redox reaction of the Rds. 相似文献