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Soyoung Kim Jaeseok Han Young-Ho Ahn Chang Hoon Ha Jung Jin Hwang Sang-Eun Lee Jae-Joong Kim Nayoung Kim 《Molecules and cells》2022,45(6):403
Hypoxia leads to significant cellular stress that has diverse pathological consequences such as cardiovascular diseases and cancers. MicroRNAs (miRNAs) are one of regulators of the adaptive pathway in hypoxia. We identified a hypoxia-induced miRNA, miR-34c, that was significantly upregulated in hypoxic human umbilical cord vein endothelial cells (HUVECs) and in murine blood vessels on day 3 of hindlimb ischemia (HLI). miR-34c directly inhibited BCL2 expression, acting as a toggle switch between apoptosis and autophagy in vitro and in vivo. BCL2 repression by miR-34c activated autophagy, which was evaluated by the expression of LC3-II. Overexpression of miR-34c inhibited apoptosis in HUVEC as well as in a murine model of HLI, and increased cell viability in HUVEC. Importantly, the number of viable cells in the blood vessels following HLI was increased by miR-34c overexpression. Collectively, our findings show that miR-34c plays a protective role in hypoxia, suggesting a novel therapeutic target for hypoxic and ischemic diseases in the blood vessels. 相似文献
24.
A recombinant plasmid pβCBD was constructed for immobilization of Cellulomonas fimi β-glucosidase (Cbg) using the cellulose-binding
domain (CBD) of Bacillus subtilis BSE 616 endo-β-1,4-glucanase (Beg). The Cbg-CBD Beg fusion protein, 80 kDa, was expressed in Escherichia coli and immobilized to Avicel. Cellobiose was completely hydrolyzed
with the immobilized fusion protein. The fusion protein bound to Avicel retained full activity during continuous operation
for 24 h at 4°C.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
25.
Tsoyi K Kim HJ Shin JS Kim DH Cho HJ Lee SS Ahn SK Yun-Choi HS Lee JH Seo HG Chang KC 《Cellular signalling》2008,20(10):1839-1847
We found that CKD712, an S enantiomer of YS49, strongly inhibited inducible nitric oxide synthase (iNOS) and NO induction but showed a weak inhibitory effect on cyclooxygenase-2 (COX-2) and PGE(2) induction in LPS-stimulated RAW 264.7 cells. We, therefore, investigated the molecular mechanism(s) responsible for this by using CKD712 in LPS-activated RAW264.7 cells. Treatment with either SP600125, a specific JNK inhibitor or TPCK, a NF-kappaB inhibitor, but neither ERK inhibitor PD98059 nor p38 inhibitor SB203580, significantly inhibited LPS-mediated iNOS and COX-2 induction. CKD712 inhibited NF-kappaB (p65) activity and translocation but failed to prevent JNK activation. However, AG490, a specific JAK-2/STAT-1 inhibitor, efficiently prevented LPS-mediated iNOS induction but not the induction of COX-2, and CKD712 completely blocked STAT-1 phosphorylation by LPS, suggesting that the NF-kappaB and JAK-2/STAT-1 pathways but not the JNK pathway are important for CKD712 action. Interestingly, CKD712 induced heme oxygenase 1 (HO-1) gene expression in LPS-treated cells. LPS-induced NF-kappaB and STAT-1 activation was partially prevented by HO-1 overexpression. Furthermore, HO-1 siRNA partly reversed not only the LPS-induced NF-kappaB activation and STAT-1 phosphorylation but also inhibition of these actions by CKD 712. Additionally, silencing HO-1 by siRNA prevented CKD712 from inhibiting iNOS expression but not COX-2. When examined plasma NO and PGE(2) levels and iNOS and COX-2 protein levels in lung tissues of mice injected with LPS (10 mg/kg), pretreatment with CKD712 greatly prevented NO and iNOS induction in a dose-dependent manner and slightly affected PGE(2) and COX-2 production as expected. Taken together, we conclude that inhibition of JAK-2/STAT-1 pathways by CKD 712 is critical for the differential inhibition of iNOS and COX-2 by LPS in vitro and in vivo where HO-1 induction also contributes to this by partially modulating JAK-2/STAT-1 pathways. 相似文献
26.
Alkaline-oxidative (A/O) pretreatment and enzymatic saccharification were optimized for bioethanol fermentation from water hyacinth by Saccharomyces cerevisiae. Water hyacinth was subjected to A/O pretreatment at various NaOH and H(2)O(2) concentrations and reaction temperatures for the optimization of bioethanol fermentation by S. cerevisiae. The most effective condition for A/O pretreatment was 7% (w/v) NaOH at 100 °C and 2% (w/v) H(2)O(2). The carbohydrate content was analyzed after reaction at various enzyme concentrations and enzyme ratios using Celluclast 1.5 L and Viscozyme L to determine the effective conditions for enzymatic saccharification. After ethanol fermentation using S. cerevisiae KCTC 7928, the concentration of glucose, ethanol and glycerol was analyzed by HPLC using a RI detector. The yield of ethanol in batch fermentation was 0.35 g ethanol/g biomass. Continuous fermentation was carried out at a dilution rate of 0.11 (per h) and the ethanol productivity was 0.77 [g/(l h)]. 相似文献
27.
Keun Soo Ahn Sung-Tae Hong Yu Na Kang Jung Hyeok Kwon Mi Jeong Kim Tae Jun Park Yong Hoon Kim Tae Jin Lim Koo Jeong Kang 《The Korean journal of parasitology》2012,50(4):357-360
A 25-year-old Uzbek male presented with right upper abdominal pain for 20 days. On radiologic studies, a huge cystic mass was noticed in the right liver which was suspected as parasitic. The patient received right hepatic segmentectomy (segment 7), and the surgically resected mass was confirmed as cystic echinococcosis (CE), measuring 10.5 cm in its diameter. The inner surface of the cyst was bile-stained. The patient was discharged on the 8th hospital day, and was rechecked 6 months after the surgical intervention without any evidence of recurrence. The present report describes findings of an imported case of CE which represented ultrasound images of the ''ball of wool''. 相似文献
28.
Simulation of sequential batch reactor (SBR) operation for simultaneous removal of nitrogen and phosphorus 总被引:3,自引:0,他引:3
Ho Nam Chang Ra Kyung Moon Byung Geon Park Seong-Jin Lim Dong Won Choi Woo Gi Lee Seok Lyong Song Yong Hee Ahn 《Bioprocess and biosystems engineering》2000,23(5):513-521
Modeling of the operation of sequential batch reactor (SBR) was performed to find out optimum design parameters for simultaneous removal of nitrogen and phosphorus in a small-scale wastewater treatment plant. The models were set up with material balances on SBR operation and Monod kinetics. The model parameters were obtained to best fit the experimental results in a small scale SBR. The models were useful in optimizing hydraulic retention time (HRT) and successfully simulated operations of SBR in a larger scale. Especially the model predicted well the reactions occurring in the filling period as well as the effect of dilution, and evaluated the performance of SBR process under diverse operating conditions. 相似文献
29.
Hye Soo Kim Bong-Gyu Kim Suhyun Sung Mihyang Kim Hyejung Mok Youhoon Chong Joong-Hoon Ahn 《Planta》2013,238(4):683-693
Flavonoids are predominantly found as glycosides in plants. The glycosylation of flavonoids is mediated by uridine diphosphate-dependent glycosyltransferases (UGT). UGTs attach various sugars, including arabinose, glucose, galactose, xylose, and glucuronic acid, to flavonoid aglycones. Two UGTs isolated from Arabidopsis thaliana, AtUGT78D2 and AtUGT78D3, showed 89 % amino acid sequence similarity (75 % amino acid sequence identity) and both attached a sugar to the 3-hydroxyl group of flavonols using a UDP-sugar. The two enzymes used UDP-glucose and UDP-arabinose, respectively, and AtUGT78D2 was approximately 90-fold more efficient than AtUGT78D3 when judged by the k cat/K m value. Domain exchanges between AtUGT78D2 and AtUGT78D3 were carried out to find UGTs with better catalytic efficiency for UDP-arabinose and exhibiting dual sugar selectivity. Among 19 fusion proteins examined, three showed dual sugar selectivity, and one fusion protein had better catalytic efficiency for UDP-arabinose compared with AtUGT78D3. Using molecular modeling, the changes in enzymatic properties in the chimeric proteins were elucidated. To the best of our knowledge, this is the first report on the construction of fusion proteins with expanded sugar-donor range and enhanced catalytic efficiencies for sugar donors. 相似文献
30.
Gye Sun Jeon Jee-Eun Kim Suk-Won Ahn Kyung-Seok Park Yoon-Ho Hong In-Hae Ye Ji-Seon Park Seung Hyun Kim Kwang-Woo Lee Sung-Min Kim Jung-Joon Sung 《Biochemical and biophysical research communications》2013
Glycogen synthase kinase-3β (GSK-3β) has been identified as one of the important pathogenic mechanisms in motor neuronal death. GSK-3β inhibitor has been investigated as a modulator of apoptosis and has been shown to confer significant protective effects on cell death in neurodegenerative diseases. However, GSK-3β is known to have paradoxical effects on apoptosis subtypes, i.e., pro-apoptotic in mitochondrial-associated intrinsic apoptosis, but anti-apoptotic in death receptor-related extrinsic apoptosis. In this study, we evaluated the effect of a new GSK-3β inhibitor (JGK-263) on motor neuron cell survival and apoptosis, by using low to high doses of JGK-263 after 48 h of serum withdrawal, and monitoring changes in extrinsic apoptosis pathway components, including Fas, FasL, cleaved caspase-8, p38α, and the Fas–Daxx interaction. Cell survival peaked after treatment of serum-deprived cells with 50 μM JGK-263. The present study showed that treatment with JGK-263 reduced serum-deprivation-induced motor neuronal apoptosis by inactivating not only the intrinsic, but also the extrinsic apoptosis pathway. These results suggest that JGK-263 has a neuroprotective effect through effective modulation of the extrinsic apoptosis pathway in motor neuron degeneration. 相似文献