• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.374-377
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• 2001

We have synthesized poly(3-hexylthiophene)(P3HT), which is the most famous conducting polymer and studied the optical properties of P3HT. And then fabricated the device using P3HT as an emitting layer. For the improve of hole injection from ITO electrode to P3HT emitting layer, we use transparent polyaniline(PANI) electrode. In the voltage-current-luminance characteristics of ITO/PANI/P3HT/LiF/Al device which use the PANI film synthesised during 5 cycle, the device turn on at the 2V and the luminance of 218 nW/$\textrm{cm}^2$ obtained at 12V. External quantum efficiency of ITO/PANI/P3HT/LiF/Al increased at 8V than that of ITO/P3HT/LiF/Al device.

• Animal cells and systems
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• v.2 no.4
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• pp.471-476
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• 1998

The G protein-activated inwardly rectifying $K^＋$ channel (GIRK1) was coex-pressed in Xenopus oocytes along with the $5-HT_{1A}$ receptor, a 7-helix receptor known to be coupled to $K^＋$ channels in many neural tissues. Thus, the activation of the $5-HT_{1A}$ receptor by its agonist leads to the opening of GIRK1. The GIRK1 current was measured using the two electrode voltage clamp technique with bath application of 5-HT in the presence of various external potassium concentrations $[K^＋]_0$. GIRK1 showed a strong inward rectification since only hyperpolarizing voltages evoked inward currents. $K^{+}$ was the major ion carrier as evidenced by about 44㎷ voltage shift corresponding to a 10-fold external 〔$K^＋$〕 change. 5-HT induced a concentration-dependent inward $K^＋$ current ($EC_{50}{\equation omitted}10.7nM$) which was blocked by $Ba^{2＋}$. Pertussis toxin (PTX) pre-treatment reduced the $K^＋$ current by as much as about 70%, suggesting that PTX-sensitive G protein ($G_i or G_o$ type) are involved in the $5-HT_{1A}$ receptor-GIRK1 coupling in Xenopus oocytes.

• Composites Research
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• v.36 no.5
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• pp.349-354
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• 2023

Poly(3-hexylthiophene) (P3HT) is a conjugated polymer that is highly soluble in organic solvents and is readily available. However, its electrical properties as an active channel in electronic devices are not enough for practical applications, necessitating further improvement in the properties. In this study, we demonstrate that the blending of two P3HT polymers (i.e., regio-regular (RR) P3HT and regio-random (RRa) P3HT) with different regioregularities can significantly improve charge transport characteristics of the blend films. The morphological and electrical properties of the blend films were systematically investigated by varying the ratio between two P3HT polymers. Atomic force microscopy (AFM), X-ray diffraction (XRD), and UV-visible absorption spectroscopy (UV-vis) were employed to evaluate the morphological and optoelectronic properties of the blend films. The crystallinity of the blend films increased with increasing the content of RRa-P3HT to 20 wt% and gradually decreased as the content increased to 80%. Consistently, the highest charge carrier mobility was obtained from the blend films containing 20 wt% RRa-P3HT, which value was measured to be 0.029 cm²/V·s. The values gradually decreased to 0.0007 cm²/V·s with increasing the content of RRa-P3HT to 80 wt%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.1
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• pp.31-35
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• 2010

This study was designed to evaluate anti-diabetes effect of Helianthus tuberosus extract (HT) in HIT-T15 cells. There were 5 experimental groups according to treatment NC (0 ${\muL/mL$), HT2 (1.1 ${\muL/mL$), HT3 (1.5 ${\muL/mL$), IN2 (1.8 ${\muL/mL$), IN3 (2.5 ${\muL/mL$). Inulin (IN) was used as a positive control for the Helianthus tuberosus extract groups. Cell viability was significantly increased in the HT3 (1.5 ${\muL/mL$), IN2 (1.8 ${\muL/mL$), IN3 (2.5 ${\muL/mL$) groups, compared with the NC group. There was no significant difference in cytotoxicity among all groups. Cell survival by MTT assay with alloxan was significantly increased in the HT2 (1.1 ${\muL/mL$), HT3 (1.5 ${\muL/mL$) groups, compared with the NC group. Insulin secretion and NAD+/NADH ratio were significantly increased in the HT3 group, compared with the NC group. We found that Helianthus tuberosus extract increased cell viability, had a protective effect on $\beta$-cells, and increased insulin secretion level and $NAD^+$/NADH ratio in HIT-T15 cells. These results suggest that Helianthus tuberosus extract improves the diabetes-related factors.

• Journal of Acupuncture Research
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• v.21 no.1
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• pp.33-50
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• 2004

Objective: The aim of this study was to investigate anti-ischemic effect of LR1 HT8 Reduction in Acupuncture Methods: I designed to investigate whether LR1 HT8 Reduction in Acupuncture affects cerebral hemodynamics [regional cerebral blood flow(rCBF), pial arterial diameter(PAD), mean arterial blood pressure(MABP)] in normal rats and to make manifest whether LR1 HT8 Reduction in Acupuncture is mediated by cyclooxygenase or guanylate cyclase. The changes of rCBF and MABP were determinated by laser-doppler flowmetry(LDF), and the change of PAD was de terminated by video microscope and width analyzer. Results: The results were as follows; 1. LR1 Reduction in Acupuncture was increased rCBF and PAD, but decreased MABP. 2. HT8 Reduction in Acupuncture was significantly increased rCBF, but decreased MABP, and increased PAD. 3. LR1 HT8 Reduction in Acupuncture was significantly increased rCBF, PAD, but decreased MABP after withdrawing of the needle. This results suggest that LR1 HT8 Reduction in Acupuncture increased significantly rCBF by dilating PAD. 4. Pretreatment with indomethacin(1mg/kg, i,v.) was significantly inhibited LR1 HT8 Reduction in Acupuncture induced increase of rCBF and PAD, but increased LR1 HT8 Reduction in Acupuncture induced decrease of MABP after withdrawing of the needle. 5. Pretreatment with methylene blue($10{\mu}g/kg$, i,v.) was decreased LR1 HT8 Reduction in Acupuncture induced increase of rCBF and PAD, but accelerated LR1 HT8 Reduction in Acupuncture induced decrease of MABP. Conclusions: I suggest that LR1 HT8 Reduction in Acupuncture has an anti-ischemic effect through the improvement of cerebral hemodynamics, and the mechanism is mediated by cyclooxygenase.

• YAKHAK HOEJI
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• v.56 no.2
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• pp.86-91
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• 2012

The objective of this study is to examine how different concentration of neurotransmitters in plasma between patients with dementia and normal people regarding the inhalation of lavender oil. This study subjects were 9 elderly patients with dementia who live in nursing home and 9 normal women. Before and after inhalation, they were collected blood sample. Norepinephrine (NE), serotonin (5-HT), dopamine (DA), and r-aminobutyric acid (GABA) concentration analysis were performed. Before inhalation, dementia patients were significantly different with the normal group in GABA and DA, NE. Following inhalation in experimental group, dementia patients and normal group were only significantly increased in 5-HT. But it did not significantly change in the other neurotransmitters. After inhalation, dementia patients were significantly different with the normal group in GABA and 5-HT. This result suggests that the increase of 5-HT release by the inhalation of lavender oil related to reduce the behavioral and psychological symptoms of dementia.

• Korean Journal of Veterinary Research
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• v.35 no.1
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• pp.39-44
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• 1995

Using immunohistochemical technique, three endocrine cell types were observed in the GIT of the Korean salamander, Hynobius leechii. BPP-immunoreactive cells were distributed from the pyloric region to the small intestine. A moderated number of somatostatin-immunoreactive cells were restricted to the pyloric region. 5-HT-immunoreactive cells were demonstrated throughout the GIT, reaching a peak in the pyloric region. The presence of BPP- and 5-HT-immunoreactive cells are identified for the first time in Hynobius leechii.

• The Korea Journal of Herbology
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• v.33 no.4
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• pp.9-18
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• 2018

Objectives : This study aimed to investigate the anti-ulcer effect of an standardized herbal extracts mixture of Inulae Flos and Paeoniae Radix (HT074) on acidified ethanol induced gastric injury and its potential mechanisms. Methods : Antioxidant activities of HT074 and its constituents were measured by DPPH (2,2-Diphenyl-1-picrylhydrazyl) and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging capacity. After the oral administration of HT074 at doses of 100, 300 mg/kg twice per day for 14 days, Gastric lesions were induced by oral administration of acidified ethanol in Sprague Dawley rats. Oxidative stress markers, such as super oxide dismutase (SOD) activity, concentrations of catalase (CAT) and glutathione (GSH) were measured in gastric mucosal tissues. Additionally, the expression of human mucin gene, Mucin 5AC (MUC5AC) mRNA in gastric mucosal tissues was measured. Results : HT074 showed dose dependent radical scavenging activities against DPPH and ABTS radicals. Oral administration of HT074 300 mg/kg for 14 consecutive days significantly decreased gastric lesions and histological damages induced by HCl/EtOH in rats. HT074 treatment significantly increased the activity of SOD (300 mg/kg) and concentration of GSH (100 and 300 mg/kg), however catalase concentration was not significantly increased. MUC5AC mRNA expression was significantly increased by HT074 100, 300 mg/kg treatment. Conclusions : HT074 protects the gastric mucosa from oxidative stress caused by acidified ethanol by increasing the activity of SOD, concentration of GSH and mucin biosynthesis. These findings suggest that HT074 could be an effective candidate for prevention and treatment of gastritis and gastric ulcer.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.51-51
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• 2001

Cocaine and amphetamine-regulated transcript (CART) is a satiety factor that is regulated by leptin. It was reported that the mice intracerebroventricularly injected with CART showed behavioral changes resembled with the typical behavioral alterations found in the mice carrying disorders in the brain serotonergic (5-HT) system. Hence, this study was conducted to find out the relationships between CART and 5-HT. We first examined the mRNA levels of CART after the injections of para-chlorophenylalanine (pCPA, 300 mg/kg i.p., single injection or daily for three consecutive days) in the rat brains by in situ hybridization using the mouse CART cDNA probe cloned in our laboratory. Systemic administrations of pCPA, a potent inhibitor of tryptophan hydroxylase, the rate limiting enzyme of 5-HT biosynthesis, acutely depletes the brain 5-HT transporter (5-HTT) in the dorsal raphe nucleus (DRN), which reuptakes terminal 5-HT. Results indicated that the mRNA level of CART significantly decreased in the arcuate nucleus, paraventricular nucleus, and lateral hypothalamic nucleus by three days of daily injection with pCPA with no noticeable change detected 24 hrs after the single injection. The message levels of 5-HTT in DRN decreased in both single and three days of injections. Secondly, to investigate whether CART affect to 5-HT, mouse genomic CART gene, which is consist of 3 exons and 2 introns and mouse neurofilament light (NF-L) chain promoter were cloned. Then, we constructed neuron specific expression vector, which was transfected into HeLa cell using lipid-mediated transfection system. Expression of GFP and CART linked to NF-L-chain promoter in the transfected HeLa cell were detected by using fluorescent microscope and RT-PCR. These results confirmed normal expression of DNA constructs in vitro. Then, to increase brain specific expression of CART in vivo transgenic mice carrying CART gene controlled the deleted NF-L-chain promoter were generated by the DNA microinjection into pronuclei of fertilized embryos. Transgenic mice were detected by Southern blot. Further study is necessary to examine CART expression and 5-HTT in these transgenic mice. Therefore, these results suggest that there maybe a positive molecular correlation between CART and 5-HT in responding to the stimuli.

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.6
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• pp.293-297
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• 2002

The role of 5-hydroxytryptamine $(5-HT)_1A$ receptor activity in prenatal ischemia was studied, by injecting 8-hydroxy-dipropylaminotetraline (8-OH-DPAT; $50{\mu}g/kg,$ s.c.), a $5-HT_1A$ agonist on gestation day 17, and 30 min later inducing transient ischemia by ligating the uterine vessels for 30 min. On postnatal day 95, rats that had experienced prenatal ischemia showed impaired motor coordination and reduced concentration of 5-HT in the cerebellum compared with Sham-operated controls. In addition, they showed increased $5-HT_1A$ receptor densities in the cerebral cortex. Pretreatment with 8-OH-DPAT ameliorated the behavioral and neurochemical sequelae measured in the present study. The results suggest that $5-HT_1A$ receptors protect the brain from ischemic insult and/or facilitate recovery after prenatally experienced ischemia.