• The Korean Journal of Physiology and Pharmacology
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• v.22 no.2
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• pp.173-182
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• 2018

Recent studies have provided several lines of evidence that peripheral administration of oxytocin induces analgesia in human and rodents. However, the exact underlying mechanism of analgesia still remains elusive. In the present study, we aimed to identify which receptor could mediate the analgesic effect of intraperitoneal injection of oxytocin and its cellular mechanisms in thermal pain behavior. We found that oxytocin-induced analgesia could be reversed by $d(CH_2)_5[Tyr(Me)^2,Dab^5]$ AVP, a vasopressin-1a (V1a) receptor antagonist, but not by $desGly-NH_2-d(CH_2)_5[D-Tyr^2,Thr^4]OVT$, an oxytocin receptor antagonist. Single cell RT-PCR analysis revealed that V1a receptor, compared to oxytocin, vasopressin-1b and vasopressin-2 receptors, was more profoundly expressed in dorsal root ganglion (DRG) neurons and the expression of V1a receptor was predominant in transient receptor potential vanilloid 1 (TRPV1)-expressing DRG neurons. Fura-2 based calcium imaging experiments showed that capsaicin-induced calcium transient was significantly inhibited by oxytocin and that such inhibition was reversed by V1a receptor antagonist. Additionally, whole cell patch clamp recording demonstrated that oxytocin significantly increased potassium conductance via V1a receptor in DRG neurons. Taken together, our findings suggest that analgesic effects produced by peripheral administration of oxytocin were attributable to the activation of V1a receptor, resulting in reduction of TRPV1 activity and enhancement of potassium conductance in DRG neurons.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.12 s.91
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• pp.1152-1160
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• 2004

OFDM technique was adopted as the standard of IEEE 802.1 la and it has been widely used for wireless LAN, European DVB/DAB system, Korean DMB system. In the standard of IEEE 802.11a the data packet is composed of two parts, preamble and data. Preamble is composed of short pilots and long pilots, which are used for synchronization and estimation of frequency offset and channel. We can also compensate phase noise effect in the transceiver by using above pilots. The phase noise is more complicate than frequency offset and seriously affects system performance. In this paper, we newly propose CPE and ICI simultaneous compensation method to compensate phase noise generated by transceiver oscillator and compare with previous studies. As results, phase noise effect can be significantly compensated by CPE cancellation method, PNS algorithm and our proposed CPE and ICI compensation method. Especially, the proposed CPE and ICI compensation method can achieve the best BER performance compared with original OFDM, CPE cancellation method and PNS algorithm.

• Journal of Plant Biotechnology
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• v.36 no.1
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• pp.59-63
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• 2009

Calcium ion ($Ca^{2+}$) is thought to play the important role as a second messenger for signal transduction that results in various physiological responses to cope with developmental programs and environmental changes in plant. In plant cells, the central vacuole functions as a major calcium store, which is important for both signal transduction and preventing cytotoxicity. Although there is evidence for the biochemical characterizations of a calmodulin-regulated $Ca^{2+}$-ATPase (ACA11) localized to vacuole membrane, the biological function to ACA11 in plant has not been verified. In this study, we show that the cell death as the hypersensitive response (HR) in mature leaves is induced in transgenic plant of a vacuole ACA-type $Ca^{2+}$-ATPase, ACA11. Evidence that cell death phenotype is the result of ACA11 gene silencing is provided by Western blot assay using membrane fraction proteins extracted from transgenic plant. The 3, 3'-diaminobenzidine (DAB) staining study provides that the cell death is caused by the increase of reactive oxygen species (ROS) in mature leaves of transgenic plants.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.3
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• pp.297-302
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• 2006

We investigated gonadal development and sex ratio of artificial seedlings of the oblong rockfish Sebastes oblongus, based on samplings for 370 days just after parturition. The primordial germ cells and genital ridge appeared separately under the mesentery in the yolk-sac stage larva (total length: 7.10-7.77 mm) just after parturition. The primordial germ cells and genital ridge integrated to form primordial gonad in 5-day-old larvae (7.12-9.68 mm), and then proliferation of somatic cell and germ cell occurred in the gonad, which was maintained undifferentiated until 45-days after parturition (18.6-20.4 mm). The ovarian differentiation began in the larva of 50-days old (dab) after parturition (dap) (20.0-24.5 mm). The somatic tissues elongated from the both opposite end-sites of undifferentiated gonad were consequently fused and formed a complete ovarian cavity at 60-days old dap (25.5-32.0 mm). In 80-days old dap (37.3-47.2 mm), meiosis of oogonia occurred to be chromatin nucleolus stage oocyte. The perinucleolus stage oocytes appeared at in 130-days old dap (68.0-86.0 mm), and previtellogenic stage oocytes appeared in 370-days old dap (101.0-116.0 mm). Only female was observed in the artificially produced oblong rockfish in the present study. This result revealed the effect of higher temperature on the sex determination of the oblong rockfish..

• Journal of Plant Biotechnology
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• v.38 no.1
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• pp.22-29
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• 2011

Although reactive oxygen species (ROS) are inevitable by-products of many redox reactions in eukaryotic cells, they play a crucial role as signaling molecules in many cellular processes for development and defense response to abiotic stresses. The biphasic ROS production which was peaked twice in a first transient phase and a second massive phase was occurred after treatment of abiotic stress such as oxidative stress, high salinity. This biphasic generation of ROS was followed by the biphasic production of stress hormone, ethylene. The mechanism of interactions between ROS and ethylene biosynthesis is studied in tobacco (Nicotiana tabaccum L.) plants under the abiotic stresses. The stress-induced ethylene production was significantly inhibited in RbohD-AS and RbohF-AS, in which antisense expression of NADPH oxidase genes was performed. The accumulation of ROS, which was determined by DAB and DCFH-DA staining, was significantly decreased after abiotic stresses in transgenic plants. The suppression of signaling with ethylene and ROS induced more tolerance in response to abiotic stress. The transgenic plants were more tolerant in MS medium supplemented with salinity stress in contrast with wild-type. Stress-induced cell damage determined by DNA fragmentation was decreased at phase II in those transgenic plants. Therefore, the first burst of ROS is more responsible for making a role as a signaling molecule during stress-induced response. These results suggested that ethylene and ROS act in a positive feedback cycle that results in mutual enhancement of ethylene and ROS production during stress-induced cell death.

• Journal of the Korean Society for Railway
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• v.19 no.5
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• pp.617-628
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• 2016

This paper proposes the structure of a smart transformer to improve the performance of the 60Hz main power transformer for rolling stock. The proposed smart transformer is a kind of solid state transformer that consists of semiconductor switching devices and high frequency transformers. This smart transformer would have smaller size than the conventional 60Hz main transformer for rolling stock, making it possible to operate AC electrified track efficiently by power factor control. The proposed structure employs a cascade H-Bridge converter to interface with the high voltage AC single phase grid as the rectifier part. Each H-Bridge converter in the rectifier part is connected by a Dual-Active-Bridge (DAB) converter to generate an isolated low voltage DC output source of the system. Because the AC voltage in the train system is a kind of medium voltage, the number of the modules would be several tens. To control the entire smart transformer, the inner DC voltage of the modules, the AC input current, and the output DC voltage must be controlled instantaneously. In this paper, a control algorithm to operate the proposed structure is suggested and confirmed through computer simulation.

• International Journal of Industrial Entomology and Biomaterials
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• v.27 no.2
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• pp.237-242
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• 2013

We investigated the 1-deoxynojirimycin (1-DNJ) content of extracts from silkworm larvae at each developmental stage within three silkworm varieties. We also compared the content of the following polyhydroxylated alkaloids in the silkworm extracts: 1-DNJ, fagomine, and 1,4-dideoxy-1,4-imino-d-arabinitol (DAB). In addition, we evaluated the glucose-lowering effects of silkworm extract powder in db/db mice. The 1-DNJ content was the highest in Yeonnokjam $5^{th}$ instar $3^{rd}$ d larvae and Hansaengjam $5^{th}$ instar $3^{rd}$ d larvae, which contained 18.4 mg/100 g dry weight and 18.3 mg/100 g dry weight, respectively. The $5^{th}$ instar $3^{rd}$ d larvae exhibited a higher content of 1-DNJ than that of $5^{th}$ instar $5^{th}$ d larvae among all varieties. The glucose-lowering effects of silkworm extracts and Yeonnokjam powder were tested on db/db mice, and the blood glucose levels were found to decrease significantly in the YR70 group. Silkworm extracts (180 mg/kg, 90 mg/kg, 45 mg/kg, and 22.5 mg/kg) and acarbose (50 mg/kg) were administered orally for 4 wk. Changes in water intake were not statistically significant between control and silkworm extract-treated groups. Compared to the control group, blood glucose levels in the silkworm extract powder-treated group decreased in the 22.5 mg/kg/d group after being administered for 4 wk. This decrease was statistically significant. Furthermore, biochemical changes in the AST(Aspartate aminotransferase), ALT(Alanine aminotransferase), TCHO(Total Cholesterol), TG(Triglyceride), LDL(Low density lipoprotein), and HDL(High density lipoprotein) levels in blood were not observed. However, statistically significant decreases in blood GLU in the 22.5 mg/kg/d group compared to that of the control group occurred. In addition, the epididymal fat weight of the silkworm extract powder-treated group decreased significantly in both the 22.5 mg/kg/d group and 180 mg/kg/d group compared to that of the control group, but there were no statistically significant changes in perirenal fat weight. These results demonstrate that silkworm extracts inhibit changes in blood glucose levels in model diabetic mice.

• Parasites, Hosts and Diseases
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• v.27 no.2
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• pp.109-118
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• 1989

Production of circulating specific antibodies to the lung fluke (Paragenimus westermani) by its host is well known and used in various kinds of immunodiagnostic methods, However, it has not been well documented which compartments (or structures) of the lung fluke are most responsible for the production of specific antibodies. The present immunohistochemical study was undertaken to demonstrate the antigenicity of each body compartment of p. westermani such as suckers, tegument, spines, vitelline glands, intestine, reproductive organs(male and female), and eggs. Indiret immunoperoxidase(IP) stain technique was applied, using formalin-fked, paraffin- embedded lung tissues of P westermani-infected cats sectioned in 4 Um thickness as the antigen and cat antisera (11~20 weeks of infection) as the primary antibody. Peroxidase-conjugated goat anti-cat IgG was used as the secondary antibody and diaminobensidine(DAB) as the coloring agent. Strong yellow or yellowish brown staining was regarded positive. The primary and secondary antibody dilutions were made at 1 : 500~1 : 2, 000 and 1 : 200~1 : 500 respectively, and IP stain was repeated 10 times for each dilution. A consistent result obtained was that the intestinal epithelial border, intestinal content, vitelline glands, and eggs scattered around the worm capsule showed strong positive staining, while uterine eggs and some parenchymal portions showed weak positive reaction. On the other hand, the suckers, tegument, spines, subtegumental cells, cytoplasm of intestinal epithelial cells, male reproductive organs, and ovary revealed negative staining. The body compartments showing higher antigenicity were, in the decreasing order, the intestinal epithelial border, intestinal content, eggs in the worm capsule, vitelline glands, uterine eggs, and parenchymatous portions. The intestinal epithelial border and luminal contents revealed positive staining even at a few concentration of 1 : 4, 000 primary antibody(secondary ab., 1 : 200) whereas the parenchymatous portion showed positive reaction only at higher concentrations than 1'500 (secondary ab., 1 : 200). The results suggest that the specific antibody responses of the host to p. westermani occur most strongly upon the excretes from the intestinal epithelium of the worm and e99s Produced around the worm capsule,

• The Korean Journal of Zoology
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• v.31 no.2
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• pp.111-121
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• 1988

This study was attempted to investigate the regional distribution and shapes of pancreatic endocrifle cells in the hedgehog, Erinaceus koneanus by the immunocytochemical PAP methods (Nalane, 1968; Stemberger, 1979). The tissue specimen taken from the splenic and duodenal regions of pancreas(proximai, middle and distal portions, respectively) were fixed with Bouin solution and the sections(5$\mu$ m) were followed by simple and double staining with 2 substrates, DAB and 4-CI-1-naphthol. The results were as following: Glucagon(A) cells, 13 $\mu$ m x 9.5 $\mu$ m in size, were found in the islets periphery and among the exocrine parenchyma. A cells were abundant in all the portions of splenic region and distal portion of duodenal region in contrast to a few in the proximal and middle portion of duodenal region. The shapes of the A cells were round, oval and pyramidal types. Insulin(B) cells, 11.6$\mu$m x 9.4$\mu$m in sise, were round or oval in shape and located throughout the islets. B cells were the most numerous cell types in all portions of splenic region and distal protion of duodenal region as compared with the other portions. Somatostatin(D) cells, 12.6$\mu$m x 9.1 $\mu$m in size, were round or oval in shape and found in the islets periphery and scattered in the exocrine parenchyma. These cells were rare in all the portions of splenic and duodenal region. Pancreatic polypeptide(PP) cells of various type, 12.8$\mu$ m x 8.5 $\mu$ m in size, were found in the islets periphery and among the exocrine parenchyma. PP cells were numerous in the proximal and middle portion of duodenal region, but rarely scattered in the other portions.