• YAKHAK HOEJI
• /
• v.52 no.6
• /
• pp.466-470
• /
• 2008

Human cytomegalovirus expresses an unusual protein kinase UL97, a member of ${H_V}{U_L}$ family of protein kinase. UL97 can phosphorylate nucleoside analogs such as ganciclovir as well as protein/peptide. It has previously been reported that UL97 is able to phosphorylate a KESYSVYVYKV peptide and that P+5 position (K) is important. We examined the extent of contribution of other positions (P-4 through P+6) of the peptide to be substrate of UL97 using alanine substituted peptides (Ala scanning) and deleted peptides. The result suggested that the E (P-2) is negative effect and P+5 (K) is still important. The peptide YSVYVYK is the shortest substrate enough to show high activity, which could be a starting point to develop peptidomimetic drug. This study would give important information to deeply understand the substrate specificity of UL97 and develop an antiviral drug using the small peptide identified here.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.11 no.2
• /
• pp.79-92
• /
• 2003

This study is to identify the hazard of ozone and to evaluate ozone effect that is flowed into the cabin when the airplane is flying at high altitude. For this purpose, it is studied that how ozone is generated in the air, what the effect on human body is due to the cabin ozone and what the design criteria is considering or preventing the ozone hazard. And, finally the regulations and means of compliance are studied and introduced to assure that the aircraft satisfies the design criteria related to ozone.

• Nutrition Research and Practice
• /
• v.7 no.2
• /
• pp.89-95
• /
• 2013

Dietary inorganic sulfur is the minor component in our diet, but some studies suggested that inorganic sulfur is maybe effective to treat cancer related illness. Therefore, this study aims to examine the effects of inorganic sulfur on cell proliferation and gene expression in MDA-MB-231 human breast cancer cells. MDA-MB-231 cells were cultured the absence or presence of various concentrations (12.5, 25, or 50 ${\mu}mol/L$) of inorganic sulfur. Inorganic sulfur significantly decreased proliferation after 72 h of incubation (P < 0.05). The protein expression of $ErbB_2$ and its active form, $pErbB_2$, were significantly reduced at inorganic sulfur concentrations of 50 ${\mu}mol/L$ and greater than 25 ${\mu}mol/L$, respectively (P < 0.05). The mRNA expression of $ErbB_2$ was significantly reduced at an inorganic sulfur concentration of 50 ${\mu}mol/L$ (P < 0.05). The protein expression of $ErbB_3$ and its active form, $pErbB_3$, and the mRNA expression of $pErbB_3$ were significantly reduced at inorganic sulfur concentrations greater than 25 ${\mu}mol/L$ (P < 0.05). The protein and mRNA expression of Akt were significantly reduced at an inorganic sulfur concentration of 50 ${\mu}mol/L$ (P < 0.05), but pAkt was not affected by inorganic sulfur treatment. The protein and mRNA expression of Bax were significantly increased with the addition of inorganic sulfur concentration of 50 ${\mu}mol/L$ (P < 0.05). In conclusion, cell proliferation was suppressed by inorganic sulfur treatment through the ErbB-Akt pathway in MDA-MB-231 cells.

• Journal of Korean Neurosurgical Society
• /
• v.37 no.2
• /
• pp.89-95
• /
• 2005

Objective: The biomechanical stabilities between the anterior plate fixation after anterior discectomy and fusion (ACDFP) and the posterior transpedicular fixation after ACDF(ACDFTP) have not been compared using human cadaver in bilateral cervical facet dislocation. The purpose of this study is to compare the stability of ACDFP, a posterior wiring procedure after ACDFP(ACDFPW), and ACDFTP for treatment of bilateral cervical facet dislocation. Methods: Ten human spines (C3-T1) were tested in the following sequence: the intact state, after ACDFP(Group 1), ACDFPW(Group 2), and ACDFTP(Group 3). Intervertebral motions were measured by a video-based motion capture system. The range of motion(ROM) and neutral zone(NZ) were compared for each loading mode to a maximum of 2.0Nm. Results: ROMs for Group 1 were below that of the intact spine in all loading modes, with statistical significance in flexion and extension, but NZs were decreased in flexion and extension and slightly increased in bending and axial rotation without significances. Group 2 produced additional stability in axial rotation of ROM and in flexion of NZ than Group 1 with significance. Group 3 provided better stability than Group 1 in bending and axial rotation, and better stability than Group 2 in bending of both ROM and NZ. There was no significant difference in extension modes for the three Groups. Conclusion: ACDFTP(Group 3) demonstrates the most effective stabilization followed by ACDFPW(Group 2), and ACDFP(Group 1). ACDFP provides sufficient strength in most loading modes, ACDFP can provide an effective stabilization for bilateral cervical facet dislocation with a brace.

• Annual Conference on Human and Language Technology
• /
• 2004.10d
• /
• pp.240-247
• /
• 2004

The purpose of this study was to investigate the role of phonology in lexical access of bilingual processing for Korean-English bilinguals. Four experiments have been conducted in order to adjudicate the nonselective lexical access hypothesis, which argues simultaneous phonological activation of two bilingual languages, and the selective lexical access hypothesis, which argues phonological activation of only one bilingual language. The results showed that the Korean target word processing was significantly affected by the phonological manipulation of the English prime word(Exp. 2). Similarly, the English target word processing showed the tendencies that it is affected by the phonological manipulation of the Korean prime word(Exp. 2). This results indicates that the phonological information of another bilingual language is automatically activated when we process one of bilingual languages, and the process of English, which is the second language for most Korean, is phonologically activated.

• Food Science and Preservation
• /
• v.31 no.1
• /
• pp.99-111
• /
• 2024

The antioxidant potentials of ethanolic extracts derived from Aster yomena (A. yomena) were evaluated by assessing their total phenolic and flavonoid contents and radical scavenging activities. Our findings revealed that the 60% ethanolic extract of A. yomena exhibited the most robust antioxidant properties among all extracts tested. Specifically, the IC₅₀ values for the 2,2'-azino-bis (3-ethyl benzothiazoline-6-sulfonic acid) and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activities of the 60% ethanolic extract from A. yomena were determined to be 1,640.30 ㎍/mL and 2,655.10 ㎍/mL, respectively. Moreover, the inhibitory effect on malondialdehyde increased with the 60% ethanolic extract from A. yomena. To assess the neuroprotective effects, we examined the impact of the 60% ethanolic extract from A. yomena against H₂O₂-induced cytotoxicity in HT-22 (mouse hippocampal neuronal cell line) and SK-N-MC (human neuroblastoma cell line) cells. The results demonstrated a significant improvement in cell viability and reduced intracellular oxidative stress. Furthermore, the major bioactive compounds present in the 60% ethanolic extract from A. yomena were identified as chlorogenic acid and rutin through high-performance liquid chromatography (HPLC) analysis.

• Bulletin of the Korean Chemical Society
• /
• v.34 no.11
• /
• pp.3243-3248
• /
• 2013

The tissue inhibitor of metalloproteinase-2 (TIMP-2) inhibits matrix metalloproteinases activity and modulates cellular proliferation and apoptosis. The human serum albumin-TIMP-2 with folic acid conjugate (termed HT2-folate) was synthesized to promote uptake through folate receptors (FRs), and a corresponding radio-labeled compound was prepared for tumor diagnosis by positron emission tomography (PET). $^{68}Ga$-NOTA-HT2-folate was synthesized from $^{68}Ga$ and the NOTA chelator with HT2-folate. The fusion protein was identified using MALDI-TOF mass spectrometry. The radioligand was prepared with a high radiochemical yield. Cell-surface association of $^{68}Ga$-NOTA-HT2-folate significantly increased over time in FR-positive tumor cells. In animal PET and biodistribution studies, tumor uptake was very high as early as 1 h after radioligand injection. Folate conjugation enhanced the selective receptor-targeting efficacy of HT2 in FRexpressing tumors, and its radioligand will be useful as an in vitro tool and for in vivo tumor diagnosis by PET imaging.

• Journal of Food Hygiene and Safety
• /
• v.34 no.5
• /
• pp.495-501
• /
• 2019

Aloin [1,8-Dihydroxy-10-(${\beta}$-D-glucopyranosyl)-3-(hydroxymethyl)-9(10H)-anthracenone], is a natural anthraquinone from aloe. It has been shown to have antioxidant and anticancer effects in various types of human cancer cells, but the anticancer effects of aloin in human colorectal cancer cells HT-29 have not been elucidated. In this study, possible mechanisms by which aloin exerts its apoptotic action in cultured human colorectal cancer HT-29 cells were investigated. The results of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay shows that treatment with aloin (0, 100, 200, 300 and $400{\mu}M$) reduced cell viability in a concentration-dependent manner in HT-29 and showed no effects on cell proliferation in A375SM and AGS cells. In addition, it was confirmed that apoptotic body was significantly increased as shown by 4',6-diamidino-2-phenylindole (DAPI) staining, and increased apoptosis rate by flow cytometry in HT-29 cells treated with aloin (0, 200 and $400{\mu}M$). We confirmed by western blotting that aloin activated Bax (pro-apoptotic), cleaved-poly (ADP-ribose) polymerase (PARP) and caspase-3, -8 and Bcl-2 (anti-apoptotic) were not changed compared with the control. Aloin induced up-regulation of phospho-p38 and down-regulation of phospho-extracellular signal-regulated kinase (ERK)1/2. Therefore, aloin suppressed the growth inhibitory effects by the induction of apoptosis in human colorectal cancer cells and has potential as a cancer preventive medicine.

• Journal of Life Science
• /
• v.23 no.1
• /
• pp.137-142
• /
• 2013

Human adipose-derived mesenchymal stem cells (hMSCs) are highly useful for vascular regeneration of injured or inflamed tissue. Lipopolysaccharide (LPS) is a potent activator of macrophages and stimulates macrophages to release inflammatory cytokines. In the present study, we explored the role of LPS-activated macrophages in the differentiation of hMSCs to smooth muscle cells (SMCs). We demonstrated that conditioned medium from LPS-induced macrophages (LPS CM) stimulates differentiation of hMSCs to SMCs, as evidenced by increased expression of smooth muscle-specific markers, including alpha-smooth muscle actin (${\alpha}$-SMA), smooth muscle-myosin heavy chain, and calponin. LPS induced the secretion of $PGF2{\alpha}$ from macrophages, and $PGF2{\alpha}$ treatment stimulated expression levels of SMC-specific markers in hMSCs. Furthermore, small interfering RNA-mediated silencing of the $PGF2{\alpha}$ receptor inhibited LPS CM-stimulated ${\alpha}$-SMA expression. These results suggest that LPS-activated macrophages promote differentiation of hMSCs to SMCs through a $PGF2{\alpha}$-dependent mechanism.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.4
• /
• pp.1551-1556
• /
• 2014

Background: Transient receptor potential melastatin 8 (TRPM8), a principle membrane receptor involved in calcium ion influx and cell signal transduction, has been found to be up-regulated in some cancer types, including melanomas. Efficiency of menthol, an agonist of TRPM8, in killing melanoma cancer cells has been reported previously, but the mechanisms remain unclear. We here determined whether in vitro cytotoxic effects of menthol on A-375 human malignant melanoma cells might be related to TRPM8 transcript expression. Materials and Methods: The $PrestoBlue^{(R)}$ cell viability assay was used to assess the in vitro cytotoxic effect of menthol after 24h of treatment. RT-PCR was used to quantify TRPM8 transcript expression levels in normal and menthol-treated cells. Cell morphology was observed under inverted phase contrast light microscopy. Results: TRPM8 transcript expression was found at low levels in A-375 cells and down-regulated in a potentially dose-dependent manner by menthol. Menthol exerted in vitro cytotoxic effects on A-375 cells with an $IC_{50}$ value of 11.8 ${\mu}M$, which was at least as effective as 5-fluorouracil ($IC_{50}=120{\mu}M$), a commonly applied chemotherapeutic drug. Menthol showed no dose-dependent cytotoxicity on HeLa cells, a TRPM8 non-expressing cell line. Conclusions: The cytotoxic effects on A-375 cells caused by menthol might be related to reduction of the TRPM8 transcript level. This suggests that menthol might activate TRPM8 to increase cytosolic $Ca^{2+}$ levels, which leads to cytosolic $Ca^{2+}$ imbalance and triggers cell death.