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991.
Ga Young Park Hye Min Lee Hyun Jin Yu Jee Soo Son Sang Joon Park Kyoung Seob Song 《Genes & genomics.》2018,40(12):1383-1388
The development of therapeutic bacteriophages will provide several benefits based on an understanding the basic physiological dynamics of phage and bacteria interactions for therapeutic use in light of the results of antibiotic abuse. However, studies on bacteriophage therapeutics against microbes are very limited, because of lack of phage stability and an incomplete understanding of the physiological intracellular mechanisms of phage. The major objective of this investigation was to provide opportunity for development of a novel therapeutic treatment to control respiratory diseases in swine. The cytokine array system was used to identify the secreted cytokines/chemokines after Bordetella bronchiseptica infection into swine nasal turbinate cells (PT-K75). We also performed the real-time quantitative PCR method to investigate the gene expression regulated by B. bronchiseptica infection or bacteriophage treatment. We found that B. bronchiseptica infection of PT-K75 induces secretion of many cytokines/chemokines to regulate airway inflammation. Of them, secretion and expression of IL-1β and IL-6 are increased in a dose-dependent manner. Interestingly, membrane-bound mucin production via expression of the Muc1 gene is increased in B. bronchiseptica-infected PT-K75 cells. However, cytokine production and Muc1 gene expression are dramatically inhibited by treatment with a specific B. bronchiseptica bacteriophage (Bor-BRP-1). The regulation of cytokine profiles in B. bronchiseptica-induced inflammation by B. bronchiseptica bacteriophage is essential for avoiding inappropriate inflammatory responses. The ability of bacteriophages to downregulate the immune response by inhibiting bacterial infection emphasizes the possibility of bacteriophage-based therapies as a novel anti-inflammatory therapeutic strategy in swine respiratory tracts. 相似文献
992.
Hae Sook Noh Il Woo Shin Ji Hye Ha Young-Sool Hah Seon Mi Baek Deok Ryong Kim 《Molecules and cells》2010,30(5):455-460
Autophagy has been implicated in cardiac cell death during ischemia/reperfusion (I/R). In this study we investigated how propofol,
an antioxidant widely used for anesthesia, affects the autophagic cell death induced by the myocardial I/R injury. The infarction
size in the myocardium was dramatically reduced in rats treated with propofol during I/R compared with untreated rats. A large
number of autophagic vacuoles were observed in the cardiomyocytes of I/R-injured rats but rarely in I/R-injured rats treated
with propofol. While LC3-II formation, an autophagy marker, was up-regulated in the I/R-injured myocardium, it was significantly
down-regulated in the myocardial tissues of I/R-injured and propofol-treated rats. Moreover, propofol inhibited the I/R-induced
expression of Beclin-1, and it accelerated phosphorylation of mTOR during I/R and Beclin-1/Bcl-2 interaction in cells, which
indicates that it facilitates the inhibitory pathway of autophagy. These data suggest that propofol protects the autophagic
cell death induced by the myocardial I/R injury. 相似文献
993.
Kim SJ Cho HH Kim YJ Seo SY Kim HN Lee JB Kim JH Chung JS Jung JS 《Biochemical and biophysical research communications》2005,329(1):25-31
Human mesenchymal stem cells (hMSC), that have been reported to be present in bone marrow, adipose tissues, dermis, muscles, and peripheral blood, have the potential to differentiate along different lineages including those forming bone, cartilage, fat, muscle, and neuron. Therefore, hMSC are attractive candidates for cell and gene therapy. The optimal conditions for hMSC expansion require medium supplemented with fetal bovine serum (FBS). Some forms of cell therapy will involve multiple doses, raising a concern over immunological reactions caused by medium-derived FBS proteins. In this study, we cultured human adipose stromal cells (hADSC) and bone marrow stroma cells (HBMSC) in human serum (HS) during their isolation and expansion, and demonstrated that they maintain their proliferative capacity and ability for multilineage differentiation and promote engraftment of peripheral blood-derived CD34(+) cells mobilized from bone marrow in NOD/SCID mice. Our results indicate that hADSC and hBMSC cultured in HS can be used for clinical trials of cell and gene therapies, including promotion of engraftment after allogeneic HSC transplantation. 相似文献
994.
Seung Gon Wi Byung Yeoup Chung Jin-Hong Kim Myung-Hwa Baek Dae Hwa Yang Ju-Woon Lee Jae-Sung Kim 《Journal of Plant Biology》2005,48(2):195-200
We examined ultrastructural changes of the cell organelles ofArabidopsis stems in response to gamma irradiation. Seedlings treated with 0 to 5 Gy developed normally, while height growth in plants
exposed to 50 Gy was significantly inhibited. Based on TEM observations, the chloroplasts were extremely sensitive to such
irradiation. In particular, the thylakoids were heavily swollen, some portions of the mitochondria and endoplasmic reticulum
were structurally altered, and the plasmalemma had pulled away from the cell wall in places. However, no ultrastructural changes
in cell organelles occurred at doses of 0 to 5 Gy. 相似文献
995.
996.
Jong-Hyun Jung Dong-Ho Seo Suk-Jin Ha Myoung-Chong Song Jaeho Cha Sang-Ho Yoo Tae-Jip Kim Nam-In Baek Moo-Yeol Baik Cheon-Seok Park 《Carbohydrate research》2009,344(13):1612-1619
Amylosucrase (ASase, EC 2.4.1.4) is a member of family 13 of the glycoside hydrolases that catalyze the synthesis of an α-(1→4)-linked glucan polymer from sucrose instead of an expensive activated sugar, such as ADP- or UDP-glucose. Transglycosylation reactions mediated by the ASases of Deinococcus geothermalis (DGAS) and Neisseria polysaccharea (NPAS) were applied to the synthesis of salicin glycosides with sucrose serving as the glucopyranosyl donor and salicin as the acceptor molecule. Two salicin glycoside transfer products were detected by TLC and HPLC analyses. The synthesis of salicin glycosides was very efficient with NPAS with a yield of over 90%. In contrast, DGAS specifically synthesized only one salicin transglycosylation product. The transglycosylation products were identified as α-d-glucopyranosyl-(1→4)-salicin (glucosyl salicin) and α-d-glucopyranosyl-(1→4)-α-d-glucopyranosyl-(1→4)-salicin (maltosyl salicin) by NMR analysis. The ratio between donor and acceptor had a significant effect on the type of product that resulted from the transglycosylation reaction. With more acceptors present in the reaction, more glucosyl salicin and less maltosyl salicin were synthesized. 相似文献
997.
Singaravelu G Song HO Ji YJ Jee C Park BJ Ahnn J 《Biochemical and biophysical research communications》2007,352(1):29-35
Calcineurin is a Ca2+/Calmodulin activated Ser/Thr phosphatase that is well conserved from yeast to human. In Caenorhabditis elegans, tax-6 and cnb-1 encode catalytic and regulatory subunits of calcineurin, respectively. We performed yeast two-hybrid screening using TAX-6 as a bait to identify calcineurin interacting proteins. KIN-29 is one of proteins that specifically interacted with TAX-6. KIN-29 is a Ser/Thr kinase previously shown to be involved in regulating gene expression of a subset of chemoreceptors in specific neurons. Both TAX-6 and KIN-29 are expressed in hypodermis, muscles, and neurons. Moreover, both calcineurin and kin-29 mutants exhibit similar phenotypes, namely small body size, small brood size, and slow growth. Here we describe specific genetic interaction between tax-6 and kin-29 in regulating body size, serotonin mediated egg laying, and chemoreceptor expression. 相似文献
998.
We characterized the effect of histone acetylation on the structure of a nucleosome and the interactions between two nucleosomes. In this study, nucleosomes reconstituted with the Selex "Widom 601" sequence were acetylated with the Piccolo NuA4 complex, which acetylates mainly H4 N-terminal tail lysine residues and some H2A/H3 N-terminal tail lysine residues. Upon the acetylation, we observed directional unwrapping of nucleosomal DNA that accompanies topology change of the DNA. Interactions between two nucleosomes in solution were also monitored to discover multiple transient dinucleosomal states that can be categorized to short-lived and long-lived (~1 s) states. The formation of dinucleosomes is strongly Mg(2+)-dependent, and unacetylated nucleosomes favor the formation of long-lived dinucleosomes 4-fold as much as the acetylated ones. These results suggest that the acetylation of histones by Piccolo NuA4 disturbs not only the structure of a nucleosome but also the interactions between two nucleosomes. Lastly, we suggest a structural model for a stable dinucleosomal state where the two nucleosomes are separated by ~2 nm face-to-face and rotated by 34° with respect to each other. 相似文献
999.
1000.
Meegun Hong Seung Woo Kim Sang Hak Han Dong Joon Kim Ki Tae Suk Yeon Soo Kim Myong Jo Kim Moon Young Kim Soon Koo Baik Young Lim Ham 《PloS one》2015,10(2)
ObjectiveThe role of lipopolysaccharide (LPS) and toll-like receptor 4 (TLR 4) in the pathogenesis of alcoholic liver disease (ALD) has been widely established. We evaluated the biological effects of probiotics (Lactobacillus rhamnosus R0011 and acidophilus R0052), KRG (Korea red ginseng), and urushiol (Rhus verniciflua Stokes) on ALD, including their effects on normal and high-fat diet in mice.MethodsOne hundred C57BL/6 mice were classified into normal (N) and high-fat diet (H) groups. Each group was divided into 5 sub-groups: control, alcohol, alcohol+probiotics, alcohol+KRG, and alcohol+urushiol. A liver function test, histology, electron-microscopy, interleukin (IL)-1β, tumor necrosis factor (TNF)-α, IL-6, and IL-10, and TLR 4 were evaluated and compared.ResultsIn the N group, probiotics, KRG, and urushiol significantly reduced levels of TNF-α (12.3±5.1, 13.4±3.9, and 12.1±4.3 vs. 27.9±15.2 pg/mL) and IL-1β (108.4±39.4, 75.0±51.0, and 101.1±26.8 vs. 162.4±37.5 pg/mL), which were increased by alcohol. Alcohol-induced TLR 4 expression was reduced by probiotics and urushiol (0.7±0.2, and 0.8±0.1 vs. 1.0±0.3, p<0.001). In the H group, IL-10 was significantly increased by probiotics and KRG, compared with alcohol (25.3±15.6 and 20.4±6.2 vs. 7.6±5.6 pg/mL) and TLR 4 expression was reduced by probiotics (0.8±0.2 vs. 1.0±0.3, p = 0.007).ConclusionsAlcohol-induced TLR 4 expression was down-regulated by probiotics in the normal and high-fat diet groups. Probiotics, KRG, and urushiol might be effective in the treatment of ALD by regulating the gut-liver axis. 相似文献