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61.
Jin-Ha Yoon Sung-Kyung Kim Ho-June Choi Soo-In Choi So-Youn Cha Sang-Baek Koh Hee-Taik Kang Song Vogue Ahn 《PloS one》2013,8(10)
Background
This study evaluated the relation between adiponectin and atherosclerosis in both genders, and investigated whether adiponectin provides useful additional information for assessing the risk of atherosclerosis.Methods
We measured serum adiponectin levels and other cardiovascular risk factors in 1033 subjects (454 men, 579 women) from the Korean Genomic Rural Cohort study. Carotid intima–media-thickness (CIMT) was used as measure of atherosclerosis. Odds ratios (ORs) with 95% confidence intervals (95% CI) were calculated using multiple logistic regression, and receiver operating characteristic curves (ROC), the category-free net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were calculated.Results
After adjustment for conventional cardiovascular risk factors, such as age, waist circumference, smoking history, low-density and high-density lipoprotein cholesterol, triglycerides, systolic blood pressure and insulin resistance, the ORs (95%CI) of the third tertile adiponectin group were 0.42 (0.25–0.72) in men and 0.47 (0.29–0.75) in women. The area under the curve (AUC) on the ROC analysis increased significantly by 0.025 in men and 0.022 in women when adiponectin was added to the logistic model of conventional cardiovascular risk factors (AUC in men: 0.655 to 0.680, p = 0.038; AUC in women: 0.654 to 0.676, p = 0.041). The NRI was 0.32 (95%CI: 0.13–0.50, p<0.001), and the IDI was 0.03 (95%CI: 0.01–0.04, p<0.001) for men. For women, the category-free NRI was 0.18 (95%CI: 0.02–0.34, p = 0.031) and the IDI was 0.003 (95%CI: −0.002–0.008, p = 0.189).Conclusion
Adiponectin and atherosclerosis were significantly related in both genders, and these relationships were independent of conventional cardiovascular risk factors. Furthermore, adiponectin provided additional information to conventional cardiovascular risk factors regarding the risk of atherosclerosis. 相似文献62.
Sung-Min Kim Heejaung Kim Jeong-Seon Lee Kyung Seok Park Gye Sun Jeon Jeeheun Shon Suk-Won Ahn Seung Hyun Kim Kyung Min Lee Jung-Joon Sung Kwang-Woo Lee 《PloS one》2013,8(11)
Background
Patients with ALS may be exposed to variable degrees of chronic intermittent hypoxia. However, all previous experimental studies on the effects of hypoxia in ALS have only used a sustained hypoxia model and it is possible that chronic intermittent hypoxia exerts effects via a different molecular mechanism from that of sustained hypoxia. No study has yet shown that hypoxia (either chronic intermittent or sustained) can affect the loss of motor neurons or cognitive function in an in vivo model of ALS.Objective
To evaluate the effects of chronic intermittent hypoxia on motor and cognitive function in ALS mice.Methods
Sixteen ALS mice and 16 wild-type mice were divided into 2 groups and subjected to either chronic intermittent hypoxia or normoxia for 2 weeks. The effects of chronic intermittent hypoxia on ALS mice were evaluated using the rotarod, Y-maze, and wire-hanging tests. In addition, numbers of motor neurons in the ventral horn of the spinal cord were counted and western blot analyses were performed for markers of oxidative stress and inflammatory pathway activation.Results
Compared to ALS mice kept in normoxic conditions, ALS mice that experienced chronic intermittent hypoxia had poorer motor learning on the rotarod test, poorer spatial memory on the Y-maze test, shorter wire hanging time, and fewer motor neurons in the ventral spinal cord. Compared to ALS-normoxic and wild-type mice, ALS mice that experienced chronic intermittent hypoxia had higher levels of oxidative stress and inflammation.Conclusions
Chronic intermittent hypoxia can aggravate motor neuronal death, neuromuscular weakness, and probably cognitive dysfunction in ALS mice. The generation of oxidative stress with activation of inflammatory pathways may be associated with this mechanism. Our study will provide insight into the association of hypoxia with disease progression, and in turn, the rationale for an early non-invasive ventilation treatment in patients with ALS. 相似文献63.
Hyeong-Geug Kim Jung-Hyo Cho Sa-Ra Yoo Jin-Seok Lee Jong-Min Han Nam-Hun Lee Yo-Chan Ahn Chang-Gue Son 《PloS one》2013,8(4)
The present study investigated the antifatigue effects of Panax ginseng C.A. Meyer in 90 subjects (21 men and 69 women) with idiopathic chronic fatigue (ICF) in a randomised, double-blind, placebo-controlled and parallel designed trial. A bespoke 20% ethanol extract of P. ginseng (1 g or 2 g day–1) or a placebo was administered to each group for 4 weeks, and then fatigue severity was monitored using a self-rating numeric scale (NRS) and a visual analogue scale (VAS) as a primary endpoint. Serum levels of reactive oxygen species (ROS), malondialdehyde (MDA), total glutathione (GSH) contents and glutathione reductase (GSH-Rd) activity were determined. After 4-week, P. ginseng administration decreased the total NRS score, but they were not statistically significant compared with placebo (P>0.05). Mental NRS score was significantly improved by P. ginseng administrations as 20.4±5.0 to 15.1±6.5 [95% CI 2.3∼8.2] for 1 g and 20.7±6.3 to 13.8±6.2 [95% CI −0.1∼4.2] for 2 g compared with placebo 20.9±4.5 to 18.8±2.9 [95% CI 4.1∼9.9, P<0.01]. Only 2 g P. ginseng significantly reduced the VAS score from 7.3±1.3 to 4.4±1.8 [95% CI 0.7∼1.8] compared with the placebo 7.1±1.0 to 5.8±1.3 [95% CI 2.2 ∼3.7, P<0.01]. ROS and MDA levels were lowered by P. ginseng compared to placebo. P. ginseng 1 g increased GSH concentration and GSH-Rd activity. Our results provide the first evidence of the antifatigue effects of P. ginseng in patients with ICF, and we submit that these changes in antioxidant properties contribute in part to its mechanism.
Trial Registration
Clinical Research Information Service (CRIS) KCT0000048 相似文献64.
Kyong-Hoon Ahn Seok-Kyun Kim Jong-Min Choi Sung-Yun Jung Jong-Hoon Won Moon-Jung Back Zhicheng Fu Ji-Min Jang Hae-Chan Ha Dae-Kyong Kim 《PloS one》2013,8(6)
Activation of sphingomyelinase (SMase) by extracellular stimuli is the major pathway for cellular production of ceramide, a bioactive lipid mediator acting through sphingomyelin (SM) hydrolysis. Previously, we reported the existence of six forms of neutral pH–optimum and Mg2+-dependent SMase (N-SMase) in the membrane fractions of bovine brain. Here, we focus on N-SMase ε from salt-extracted membranes. After extensive purification by 12,780-fold with a yield of 1.3%, this enzyme was eventually characterized as N-SMase2. The major single band of 60-kDa molecular mass in the active fractions of the final purification step was identified as heat shock protein 60 (Hsp60) by matrix-assisted laser desorption/ionization time-of-flight mass spectrometric analysis. Proximity ligation assay and immunoprecipitation study showed that Hsp60 interacted with N-SMase2, prompting us to examine the effect of Hsp60 on N-SMase2 and ceramide production. Interestingly, Hsp60 siRNA treatment significantly increased the protein level of N-SMase2 in N-SMase2-overexpressed HEK293 cells. Furthermore, transfection of Hsp60 siRNA into PC12 cells effectively increased both N-SMase activity and ceramide production and increased dopamine re-uptake with paralleled increase. Taken together, these results show that Hsp60 may serve as a negative regulator in N-SMase2-induced dopamine re-uptake by decreasing the protein level of N-SMase2. 相似文献
65.
Sangheun Lee Beom Kyung Kim Seung Up Kim Yehyun Park Sooyun Chang Jun Yong Park Do Young Kim Sang Hoon Ahn Chae Yoon Chon Kwang-Hyub Han 《PloS one》2013,8(10)
Background
Although sorafenib is accepted as the standard of care in advanced hepatocellular carcinoma (HCC), its therapeutic benefit is marginal. Here, we aimed to compare the efficacy and safety of sorafenib monotherapy (S-M) and sorafenib-based loco-regional treatments (S-LRTs) in advanced HCC.Methods
From 2007 to 2012, 290 patients with advanced HCC (Barcelona Clinic Liver Cancer stage C) with S-M (n = 226) or S-LRTs (n = 64) were reviewed retrospectively. Survival outcomes and treatment-related toxicities between two groups were analyzed.Results
Variables related to tumor burden and liver function were similar between the groups (all P > 0.05). Within the entire population, the S-LRTs group had both longer median overall survival (OS) (8.5 vs 5.5 months, P = 0.001) and progression-free survival (PFS) (5.3 vs 3.0 months, P = 0.002) than the S-M group. Furthermore, the S-LRTs group had longer Os than the S-M group in a subgroup with neither extrahepatic spread (EHS) nor regional nodal involvement (RNI) (18.0 vs 7.8 months, P = 0.019) and in a subgroup with EHS and/or RNI (8.3 vs 4.8 months, P = 0.028). In addition, the S-LRTs group had longer PFS than the S-M group in the subgroup with neither EHS nor RNI (9.6 vs 3.2 months, P = 0.027).Treatment
Related toxicity was similar between two groups.Conclusion
Combined use of sorafenib and LRTs may provide better treatment outcomes without significantly increasing treatment-related toxicities, even in patients with EHS and/or RNI. Therefore, addition of active LRTs might be considered, if feasible. 相似文献66.
Jun-Young Ahn Joon-Yeop Lee Eun-Ju Yang Young-Jin Lee Kyung-Bon Koo Kyung-Sik Song Kyeong-Yeoll Lee 《Journal of Asia》2013,16(3):317-320
Two anthraquinones were isolated from the symbiotic bacteria Photorhabdus temperata of entomopathogenic nematodes Heterorhabditis spp. by repeated column chromatography. They were abundantly present in the culture medium and identified as 1,3-dimethoxy-8-hydroxy-9,10-anthraquinone and 3-methoxychrysazine by spectral analysis. The isolated anthraquinones were highly lethal to larvae of Culex pipiens pallens. Our results suggest that anthraquinones might be useful as biopesticides for the biological control of mosquitoes. 相似文献
67.
Changon Seo Yun-Hyeok Choi Jong Seog Ahn Joung Han Yim Hong Kum Lee 《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):1133-1137
The selective inhibition of PTP1B has been widely recognized as a potential drug target for the treatment of type 2 diabetes and obesity. In the course of screening for PTP1B inhibitory natural products, the MeOH extract of the dried sample of the Antarctic lichen Umbilicaria antarctica was found to exhibit significant inhibitory effect, and the bioassay-guided fractionation and purification afforded three related lichen metabolites 1-3. Compounds 1-3 were identified as gyrophoric acid (1), lecanoric acid (2), and methyl orsellinate (3) mainly by analysis of NMR and MS data. These compounds inhibited PTP1B activity with 50% inhibitory concentration values of 3.6 ± 0.04 μM, 31 ± 2.7 μM, and 277 ± 8.6 μM, respectively. Furthermore, the kinetic analysis of PTP1B inhibition by compound 1 suggested that the compound inhibited PTP1B activity in a non-competitive manner. 相似文献
68.
Ahmed K. Farag Ahmed H. E. Hassan Byung Sun Ahn Ki Duk Park 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):311-324
Abstract Hybridization of reported weakly active antiproliferative hit 5-amino-4-pyrimidinol derivative with 2-anilino-4-phenoxypyrimidines suggests a series of 2,5-diamino-4-pyrimidinol derivatives as potential antiproliferative agents. Few compounds belonging to the proposed series were reported as CSF1R/DAPK1 inhibitors as anti-tauopathies. However, the correlation between CSF1R/DAPK1 signalling pathways and cancer progression provides motives to reprofile them against cancer therapy. The compounds were synthesised, characterized, and evaluated against M-NFS-60 cells and a kinase panel which bolstered predictions of their antiproliferative activity and suggested the involvement of diverse molecular targets. Compound 6e, the most potent in the series, showed prominent broad-spectrum antiproliferative activity inhibiting the growth of hematological, NSCLC, colon, CNS, melanoma, ovarian, renal, prostate and breast cancers by 84.1, 52.79, 72.15, 66.34, 66.48, 51.55, 55.95, 61.85, and 60.87%, respectively. Additionally, it elicited an IC50 value of 1.97?µM against M-NFS-60 cells and good GIT absorption with Pe value of 19.0?±?1.1?×?10?6?cm/s (PAMPA-GIT). Molecular docking study for 6e with CSF1R and DAPK1 was done to help to understand the binding mode with both kinases. Collectively, compound 6e could be a potential lead compound for further development of anticancer therapies. 相似文献
69.
Woong-Hee Kim Pyeonghwa Jeong Seon-Wook Kim Haaglim Cho Jeong-min Lee Shinae Seo Haihong Shen Youngkeun Ahn Da-Woon Jung Yong-Chul Kim Darren R. Williams 《Bioorganic & medicinal chemistry》2019,27(13):2923-2934
Indirubin-based compounds affect diverse biological processes, such as inflammation and angiogenesis. In this study, we tested a novel indirubin derivative, LDD-1819 (2-((((2Z,3E)-5-hydroxy-5′-nitro-2′-oxo-[2,3′-biindolinylidene]-3-ylidene)amino)oxy)ethan-1-aminium chloride) for two major biological activities: cell plasticity and anti-cancer activity. Biological assays indicated that LDD-1819 induced somatic cell plasticity. LDD-1819 potentiated myoblast reprogramming into osteogenic cells and fibroblast reprogramming into adipogenic cells. Interestingly, in an assay of skeletal muscle dedifferentiation, LDD-1819 induced human muscle cellularization and blocked residual proliferative activity to produce a population of mononuclear refractory cells, which is also observed in the early stages of limb regeneration in urodele amphibians. In cancer cell lines, LDD-1819 treatment inhibited cell invasion and selectively induced apoptosis compared to normal cells. In an animal tumor xenograft model, LDD-1819 reduced human cancer cell metastasis in vivo at doses that did not produce toxicity. Biochemical assays showed that LDD-1819 possessed inhibitory activity against glycogen synthase kinase-3β, which is linked to cell plasticity, and aurora kinase, which regulates carcinogenesis. These results indicate that novel indirubin derivative LDD-1819 is a dual inhibitor of glycogen synthase kinase-3β and aurora A kinase, and has potential for development as an anti-cancer drug or as a reprogramming agent for cell-therapy based approaches to treat degenerative diseases. 相似文献
70.
Cho Bumrae Lee Eun-Jin Ahn Sun Mi Kim Ghangyong Lee Sang Hoon Ji Dal-Young Kang Jung-Taek 《Transgenic research》2019,28(5-6):549-559
Transgenic Research - Islet xenotransplantation is a promising treatment for type I diabetes. Numerous studies of islet xenotransplantation have used pig-to-nonhuman primate transplantation models.... 相似文献