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991.
Young Rae Ji Hei Jung Kim Dong Hun Yu Ki Beom Bae Seo Jin Park Si Jun Park Woo Young Jang Min-Cheol Kang Jain Jeong Yong Hun Sung Minjee Choi Taejun Park Taesun Park Jong Won Yun Hyun-Shik Lee Sanggyu Lee Myoung Ok Kim Zae Young Ryoo 《Biochemical and biophysical research communications》2014
Chronic hepatitis is a major cause of liver cancer, so earlier treatment of hepatitis might be reducing liver cancer incidence. Hepatitis can be induced in mice by treatment with Concanavalin A (Con A); the resulting liver injury causes significant CD4+ T cell activation and infiltration. In these T cells, Roquin, a ring-type E3 ubiquitin ligase, is activated. To investigate the role of Roquin, we examined Con A-induced liver injury and T cell infiltration in transgenic (Tg) mice overexpressing Roquin specifically in T cells. In Roquin Tg mice, Con A treatment caused greater increases in both the levels of liver injury enzymes and liver tissue apoptosis, as revealed by TUNEL and H&E staining, than wild type (WT) mice. Further, Roquin Tg mice respond to Con A treatment with greater increases in the T cell population, particularly Th17 cells, though Treg cell counts are lower. Roquin overexpression also enhances increases in pro-inflammatory cytokines, including IFN-γ, TNF-α and IL-6, upon liver injury. Furthermore, Roquin regulates the immune response and apoptosis in Con A induced hepatitis via STATs, Bax and Bcl2. These findings suggest that over-expression of Roquin exacerbates T-cell mediated hepatitis. 相似文献
992.
Kwon Jeong Seong-Jin Kim Yoojung Oh Hunsung Kim Young-Seok Lee Byung-Su Kwon Sanghyun Park Key-Chung Park Kyung-Sik Yoon Sung Soo Kim Joohun Ha Insug Kang Wonchae Choe 《Biochemical and biophysical research communications》2014
Accumulating evidence suggests that endoplasmic reticulum (ER) stress plays a major role in the development of many diseases. A previous study indicated that the apoptotic regulator p53 is significantly increased in response to ER stress and participates in ER stress-induced apoptosis. However, the regulators of p53 expression during ER stress are still not fully understood. Here, we investigated whether p53 contributes to the impairment of Pin1 signaling under ER stress. We found that treatment with thapsigargin, a stimulator of p53 expression and an inducer of ER stress, decreased Pin1 expression in HCT116 cells. Also, we identified functional p53 response elements (p53REs) in the Pin1 promoter. Overexpression of p53 significantly decreased Pin1 expression in HCT116 cells while abolition of p53 gene expression induced Pin1 expression. Pin1 expression was significantly increased by treatment with the p53 inhibitor pifithrin-α or down-regulation of p53 expression. Taken together, ER stress decreased Pin1 expression through p53 activation, and this mechanism may be associated with ER stress-induced cell death. These data reported here support the importance of Pin1 as a potential target molecule mediating tumor development. 相似文献
993.
994.
Mao S Lee SJ Hwangbo H Kim YW Park KH Cha GS Park RD Kim KY 《Current microbiology》2006,53(5):358-364
A new antagonistic Burkholderia strain, designated MP-1 and producing antifungal activities against various filamentous plant pathogenic fungi, was isolated
from the rhizoshere in the Naju area. Cultural characteristic studies strongly suggested that this strain belongs to the genus
Burkholderia. The nucleotide sequence of the 16S rRNA gene (1491 pb) of strain MP-1 exhibited close similarity (99% to 100%) with other
Burkholderia 16S rRNA genes. Extraction of fermentation broth of Burkholderia sp. MP-1 and various separations and purification steps led to isolation of four pure active molecules. The chemical structure
of these four compounds—named phenylacetic acid, hydrocinnamic acid, 4-hydroxyphenylacetic acid, and 4-hydroxyphenylacetate
methyl ester—was established on the basis on their gas chromatography–electron impact–mass spectrometry (GC-EI-MS) and trimethylsilation
GC-EI-MS data. The four isolated compounds inhibited filamentous fungal growth on potato dextrose agar medium supplemented
with 100 mg/L of phenylacetic acid, hydrocinnamic acid, 4-hydroxyphenylacetic acid and 4-hydroxyphenylacetate methyl ester
individually. 相似文献
995.
Jong Wan Park Ho Sub Jung Hea Yeon Lee Tomoji Kawai 《Biotechnology and Bioprocess Engineering》2005,10(6):505-509
For the purpose of developing a direct label-free electrochemical detection system, we have systematically investigated the
electrochemical signatures of each step in the preparation procedure, from a bare gold electrode to the hybridization of label-free
complementary DNA, for the streptavidin-modified electrode. For the purpose of this investigation, we obtained the following
pertinent data; cyclic voltammogram measurements, electrochemical impedance spectra and square wave voltammogram measurements,
in Fe(CN)6
3−/Fe(CN)6
4− solution (which was utilized as the electron transfer redox mediator). The oligonucleotide molecules on the streptavidin-modified
electrodes exhibited intrinsic redox activity in the ferrocyanide-mediated electrochemical measurements. Furthermore, the
investigation of electrochemical electron transfer, according to the sequence of oligonucleotide molecules, was also undertaken.
This work demonstrates that direct label-free oligonucleotide electrical recognition, based on biofunctional streptavidin-modified
gold electrodes, could lead to the development of a new biosensor protocol for the expansion of rapid, cost-effective detection
systems. 相似文献
996.
Kang HW Park JY Jeong SW Kim JA Moon HJ Perez-Reyes E Lee JH 《The Journal of biological chemistry》2006,281(8):4823-4830
Molecular cloning studies have revealed that heterogeneity of T-type Ca2+ currents in native tissues arises from the three isoforms of Ca(v)3 channels: Ca(v)3.1, Ca(v)3.2, and Ca(v)3.3. From pharmacological analysis of the recombinant T-type channels, low concentrations (<50 microM) of nickel were found to selectively block the Ca(v)3.2 over the other isoforms. To date, however, the structural element(s) responsible for the nickel block on the Ca(v)3.2 T-type Ca2+ channel remain unknown. Thus, we constructed chimeric channels between the nickel-sensitive Ca(v)3.2 and the nickel-insensitive Ca(v)3.1 to localize the region interacting with nickel. Systematic assaying of serial chimeras suggests that the region preceding domain I S4 of Ca(v)3.2 contributes to nickel block. Point mutations of potential nickel-interacting sites revealed that H191Q in the S3-S4 loop of domain I significantly attenuated the nickel block of Ca(v)3.2, mimicking the nickel-insensitive blocking potency of Ca(v)3.1. These findings indicate that His-191 in the S3-S4 loop is a critical residue conferring nickel block to Ca(v)3.2 and reveal a novel role for the S3-S4 loop to control ion permeation through T-type Ca2+ channels. 相似文献
997.
Metabolic acids produced by oral pathogens demineralize tooth surfaces, leading to dental caries. Glucosyltransferases are the key factor in this process. We synthesized various modified oligosaccharides and tested them for their inhibitory effects on glucosyltransferase activity. Oligosaccharides were produced using a mixed-culture fermentation of Lipomyces starkeyi and Leuconostoc mesenteroides and then further modified as iron- and sulfate-oligosaccharides. Iron- and sulfate-oligosaccharides reduced glucosyltransferase activity of Streptococci from 17% to 43% and prevented the formation of insoluble biomass on the surface of glass vials or stainless steel wires in the presence of sucrose. They also reduced the growth and acid productions of oral pathogens including S. mutans, S. sobrinus, Eikenella corrodens, Prevotella intermedia, and Actinobacillus actinomycetemcmitans. 相似文献
998.
999.
Ultrafine oxidized cellulose (OC) mats were prepared by oxidation of ultrafine cellulose mats produced by electrospinning and subsequent deacetylation of cellulose acetate for potential applications in nonwoven adhesion barriers. When ultrafine cellulose mats were oxidized with a mixture of HNO3/H3PO4 - NaNO2 (2/1/1.4 v/v/wt %), their ultrafine mat structure remained unchanged. The yield and carboxyl content of OC mats were 86.7% and 16.8%, respectively. OC showed lower crystallinity than cellulose because the oxidation of cellulose proceeded via disruption of hydrogen bonds between cellulose chains. The swelling behaviors of ultrafine OC mats were dependent on the type of swelling solution. In a physiological salt solution, their degree of swelling was approximately 230%. 相似文献
1000.