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191.
Eun Hyun Seo Dong Young Lee Jong-Min Lee Jun-Sung Park Bo Kyung Sohn Young Min Choe Min Soo Byun Hyo Jung Choi Jong Inn Woo 《PloS one》2013,8(12)
This study aimed to investigate the influence of apolipoprotein E (APOE) ε4 allele on whole-brain functional networks in cognitively normal (CN) elderly by applying graph theoretical analysis to brain glucose metabolism. Eighty-six CN elderly [28 APOE ε4 carriers (ε4+) and 58 non-carriers (ε4-)] underwent clinical evaluation and resting [18F] fluorodeoxyglucose positron emission tomography scan. Whole-brain functional networks were constructed from correlations of the 90 regions of interest using the automated anatomical labeling template, and analyzed using graph theoretical approaches. The overall small-world property seen in ε4- was preserved in ε4+. However, both local clustering and path length were lower in ε4+ compared to ε4-. In terms of the hubs of functional networks, ε4+ showed decreased centrality of the right hippocampus but increased centrality of several brain regions associated with the default mode network compared to ε4-. Our results indicate that genetic vulnerability to Alzheimer’s disease may alter whole-brain functional networks even before clinical symptoms appear. 相似文献
192.
193.
Young-Mo Ryu Young-Sool Hah Bong-Wook Park Deok Ryong Kim Gu Seob Roh Jong-Ryoul Kim Uk-Kyu Kim Gyu-Jin Rho Geun-Ho Maeng June-Ho Byun 《Molecular biology reports》2011,38(5):2887-2894
This study examined the osteogenic differentiation of cultured human periosteal-derived cells grown in a three dimensional
collagen-based scaffold. Periosteal explants with the appropriate dimensions were harvested from the mandible during surgical
extraction of lower impacted third molar. Periosteal-derived cells were introduced into cell culture. After passage 3, the
cells were divided into two groups and cultured for 28 days. In one group, the cells were cultured in two-dimensional culture
dishes with osteogenic inductive medium containing dexamethasone, ascorbic acid, and β-glycerophosphate. In the other group,
the cells were seeded onto a three-dimensional collagen scaffold and cultured under the same conditions. We examined the bioactivity
of alkaline phosphatase (ALP), the RT-PCR analysis for ALP and osteocalcin, and measurements of the calcium content in the
periosteal-derived cells of two groups. Periosteal-derived cells were successfully differentiated into osteoblasts in the
collagen-based scaffold. The ALP activity in the periosteal-derived cells was appreciably higher in the three-dimensional
collagen scaffolds than in the two-dimensional culture dishes. The levels of ALP and osteocalcin mRNA in the periosteal-derived
cells was also higher in the three-dimensional collagen scaffolds than in the two-dimensional culture dishes. The calcium
level in the periosteal-derived cells seeded onto three-dimensional collagen scaffolds showed a 5.92-fold increase on day
7, 3.28-fold increase on day 14, 4.15-fold increase on day 21, and 2.91-fold increase on day 28, respectively, compared with
that observed in two-dimensional culture dishes. These results suggest that periosteal-derived cells have good osteogenic
capacity in a three-dimensional collagen scaffold, which provides a suitable environment for the osteoblastic differentiation
of these cells. 相似文献
194.
195.
Suk J Kwak SS Lee JH Choi JH Lee SH Lee DH Byun B Lee GH Joe CO 《Journal of cellular biochemistry》2011,112(9):2566-2573
The activation of autophagic pathway by alkaline stress was investigated. Various types of mammalian cells were subjected to alkaline stress by incubation in bicarbonate buffered media in humidified air containing atmospheric 0.04% CO(2) . The induction of autophagy following alkaline stress was evaluated by assessing the conversion of cytosolic LC3-I into lipidated LC3-II, the accumulation of autophagosomes, and the formation of autolysosomes. Colocalization of GFP-LC3 with endolysosomal marker in HeLa GFP-LC3 cells undergoing autophagic process by alkaline stress further demonstrates that autophagosomes triggered by alkaline stress matures into autolysosomes for the lysosome dependent degradation. We found that the inactivation of mTORC1 is important for the pathway leading to the induction of autophagy by alkaline stress since the expression of RhebQ64L, a constitutive activator of mTORC1, downregulates the induction of autophagy after alkaline stress in transfected human 293T cells. These results imply that activation of autophagic pathway following the inactivation of mTORC1 is important cellular events governing alkaline stress-induced cytotoxicity and clinical symptoms associated with alkalosis. 相似文献
196.
197.
Maitra D Byun J Andreana PR Abdulhamid I Diamond MP Saed GM Pennathur S Abu-Soud HM 《Free radical biology & medicine》2011,51(2):374-386
Hypochlorous acid (HOCl) is generated by myeloperoxidase using chloride and hydrogen peroxide as substrates. HOCl and its conjugate base (OCl−) bind to the heme moiety of hemoglobin (Hb) and generate a transient ferric species whose formation and decay kinetics indicate it can participate in protein aggregation and heme destruction along with subsequent free iron release. The oxidation of the Hb heme moiety by OCl− was accompanied by marked heme destruction as judged by the decrease in and subsequent flattening of the Soret absorbance peak at 405 nm. HOCl-mediated Hb heme depletion was confirmed by HPLC analysis and in-gel heme staining. Exposure of Hb to increasing concentrations of HOCl produced a number of porphyrin degradation products resulting from oxidative cleavage of one or more of the carbon-methene bridges of the tetrapyrrole ring, as identified by their characteristic HPLC fluorescence and LC-MS. A nonreducing denaturing SDS-PAGE showed several degrees of protein aggregation. Similarly, porphyrin degradation products were identified after exposure of red blood cells to increasing concentrations of HOCl, indicating biological relevance of this finding. This work provides a direct link between Hb heme destruction and subsequent free iron accumulation, as occurs under inflammatory conditions where HOCl is formed in substantial amounts. 相似文献
198.
Subin Lee Badriah Alkathiri Dongmi Kwak Sang-Myeong Lee Wan-Kyu Lee Jae-Won Byun Seung-Hun Lee 《The Korean journal of parasitology》2022,60(3):207
This study aimed to examine the distribution of gastrointestinal parasitic infections in domestic pigs in the Republic of Korea. From May 2020 to October 2021, 364 pig fecal samples were collected from 75 farms in 7 Provinces and microscopically examined. A total of 170 (46.7%) pigs were infected with at least one of the following parasites: Balantioides coli, strongyles, Ascaris suum, Trichuris suis, and coccidia. By parasite species, B. coli, strongyles, A. suum, T. suis, and coccidia oocysts or eggs were detected in 144 (39.6%), 24 (6.6%), 14 (3.8%), 4 (1.1%), and 1 (0.3%) samples, respectively. One hundred fifty-four, 15, and 1 cases showed single, double, and triple infections, respectively. Of the swine fecal samples from 75 farms, 69 specimens (92.0%) were infected with 1 or more parasites. All surveyed farms across the country exhibited a positive rate of over 30%, among which the highest positive rate was 65.0% in Chungcheongnam-do, and Jeollabuk-do was followed by 61.9%. Winter showed a statistically lower prevalence than other seasons. This study showed that gastrointestinal parasites are prevalent in pigs in Korea, although the diversity of parasites is low. 相似文献
199.
Recent studies have shown DAPk as a molecular modulator induced by the second messenger, responsible for controlling cell destiny decisions, but the detailed mechanism mediating the role of DAPk1 during cell death is still not fully understood. In this present report, we attempted to characterize the effects of TNF-α and INF-γ on DAPk1 in human ovarian carcinoma cell lines, OVCAR-3. Both TNF-α and INF-γ significantly induce DAPk1 levels in a time-dependent manner. At the same time, they both arrested cell cycle progression in the G(0)-G(1) and G2/M phase, down-regulated cyclin D1, CDK4 and NF-κB expression, while also up-regulating p27 and p16 expression. Subsequently, the efficacy of the combined treatment with DAPk1 was investigated. In the presence of DAPk1, TNF-α or INF-γ-induced apoptosis was additively increased, while TNF-α or INF-γ-induced NF-κB activity was inhibited. Conversely, TNF-α or INF-γ-dependent NF-κB activity was further enhanced by the inhibition of DAPk1 with its specific siRNA. The activity of NF-κB was dependent on the level of DAPk1, indicating the requirement of DAPk1 for the activation of NF-κB. Low levels of DAPk1 expression were frequently observed in different human patient's tissue and cancer cell lines compared to normal samples. In addition, over-expression of DAPk1 from either TNF-α or INF-γ-treatment cells suppressed the anti-apoptosis protein XIAP as well as COX-2 and ICAM-1, more than control. Taken together, our data findings suggest that DAPk1 can mediate the pro-apoptotic activity of TNF-α and INF-γ via the NF-κB signaling pathways. 相似文献
200.
Sangchul Lee Seong Jin Jeong Sung Il Hwang Sung Kyu Hong Hak Jong Lee Seok Soo Byun Gheeyoung Choe Sang Eun Lee 《PloS one》2015,10(4)