• International Journal of Oral Biology
• /
• v.39 no.2
• /
• pp.107-114
• /
• 2014

Taste is an important sense in survival and growth of animals. The growth and maintenance of taste buds, the receptor organs of taste sense, are under the regulation of various neurotrophic factors. But the distribution aspect of neurotrophic factors and their receptors in distinct taste cell types are not clearly known. The present research was designed to characterize mRNA expression pattern of neurotrophic factors and their receptors in distinct type of taste cells. In male 45-60 day-old Sprague-Dawley rats, epithelial tissues with and without circumvallate and folliate papillaes were dissected and homogenized, and mRNA expressions for neurotrophic factors and their receptors were determined by RT-PCR. The mRNA expressions of brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT3), receptor tyrosine kinase B (TrkB), exclusion of nerve growth factor (NGF), neurotrophin-4/5 (NT4/5), receptor tyrosine kinase A (TrkA), receptor tyrosine kinase C (TrkC), and p75NGFR were observed in some population of taste cell. In support of this result and to characterize which types of taste cells express NT3, BDNF, or TrkB, we examined mRNA expressions of NT3, BDNF, or TrkB in the $PLC{\beta}2$ (a marker of Type II cell)-and/or SNAP25 (a marker of Type III cell)-positive taste cells by a single taste cell RT-PCR and found that the ratio of positively stained cell numbers were 17.4, 6.5, 84.1, 70.3, and 1.4 % for $PLC{\beta}2$, SNAP25, NT3, BDNF, and TrkB, respectively. In addition, all of $PLC{\beta}2$-and SNAP25-positive taste cells expressed NT3 mRNA, except for one taste bud cell. The ratios of NT3 mRNA expressions were 100% and 91.7% in the SNAP25-and $PLC{\beta}2$-positive taste cells, respectively. However, two TrkB-positive taste cells co-expressed neither $PLC{\beta}2$ nor SNAP 25. The results suggest that the most of type II or type III cells express BDNF and NT3 mRNA, but the expression is shown to be less in type I taste cells.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.19 no.6
• /
• pp.1085-1094
• /
• 1994

We propose a traffic flow control scheme of B-NT with temporary cell buffering and selective cell discarding to prevent congestion state of the network nodes in B-ISDN systems to reduce or suppress output cell strams towards T interface. We define the states of the network nodes as normal, pre-congestion, and congestion. In a pre-congestion state, the loss-sensitive traffic is temporarily buffered to slow down the rate of the output traffic streams. In a congestion state, the delay-sensitive traffic is selectively discarded to suppress the output traffic streams as possible in addition to the cell buffering. We model the input cell streams and the states of the network nodes with Interrupted Bernoulli Process and 3-state Markov chain to analyze the performance of the proposed scheme in the B-NT system. The appropriate size of the cell buffer is explored by means of simulation and the influence on the performance of the proposed scheme by the network node state is discussed. As results, more than 2,00 cells of buffer size is needed for the control of medium of lower than the medium, degree of congestion occurrence in the network node while the control of high degree of congestion occurrence is nearly impossible.

• Journal of Genetic Medicine
• /
• v.14 no.1
• /
• pp.1-7
• /
• 2017

Purpose: The aim of this study was to assess the diagnostic efficacy of noninvasive prenatal screening for trisomy 18 by assessing the levels of unmethylated-maspin (U-maspin) and fetal nuchal translucency (NT) thickness during the first trimester of pregnancy. Materials and Methods: A nested case-control study was conducted using maternal plasma samples collected from 65 pregnant women carrying 11 fetuses with trisomy 18 and 54 normal fetuses. We compared the U-maspin levels, NT thicknesses, or a combination of both in the first trimester between the case and control groups. Results: U-maspin levels and NT thickness were significantly elevated in the first trimester in pregnant women carrying fetuses with trisomy 18 when compared to those carrying normal fetuses (27.2 vs. 6.6 copies/mL, P<0.001 for U-maspin; 5.9 vs. 2.0 mm, P<0.001 for NT). The sensitivities of the U-maspin levels and NT thickness in prenatal screening for fetal trisomy 18 were 90.9% and 90.9%, respectively, with a specificity of 98.1%. The combined U-maspin levels and NT thickness had a sensitivity of 100% in prenatal screening for fetal trisomy 18, with a specificity of 98.1%. Conclusion: A combination of U-maspin levels and NT thickness is highly efficacious for noninvasive prenatal screening of fetal trisomy 18 in the first trimester of pregnancy.

• Proceedings of the Korean Society of Developmental Biology Conference
• /
• 2003.10a
• /
• pp.109-109
• /
• 2003

Even though success in birth of live offspring from nuclear transfer(NT) using somatic cells in many species, detailed information on processes or mechanisms of development are not well known. Cytoplasm of bovine oocyte has been known to support the development of nuclear transferred embryos using nuclear donor cells from different species. Therefore, interspecies NT might be used to find answers of some questions in basic aspect of nuclear transfer In this study, we examined the developmental potential of reconstructed embryos when bovine oocyte as a cytoplasm recipient and mouse embryonic fibroblast as a nuclear donor were used. The nuclear transfer units were aliocated in Group 1 (murine block media and normal media) and Group 2. (bovine block media and normal media). NT units were not blocked at 2-cell stage regardless of types of medium. On mouse media, poor development of interspecies NT units was observed compared to bovine media. However, as NT units cultured in bovine normal medium, embryos developed over 8-cell stage. Further studies performed to increase the developmental rate in condition of antioxidant treatment. Despite low development, bovine-murine interspecies nuclear transferred embryos could develop to blastocysts and they showed that blastocyts rate of antioxidant group was superior to those of non-antioxidant group. Next, we investigated gene expression pattern which is carried out for zygotic activation. The Xist gene is expressed in female mouse embryo after zygotic activation of 4-cell stage. But interspecies nuclear transferred embryos do not express Xist gene at 4-cell stage. As a result, it is suggested that the bovine cytoplasm controls the early preimplantation development in interspecies NT However, the development of later stages might require genomic control from transferred donor nucleus. Therefore, even though the involvement of several other factors such as mitochondrial incompatibility, effective development of embryos produced by interspecies NT requires proper genomic activation of donor nucleus after overcoming the cytoplasmic control of recipient oocytes.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.314-314
• /
• 2017

Anthropogenic activities have increased the concentrations of greenhouse gases, such as $CO_2$, $CH_4$, $N_2O$, HFCs, $SF_6$, and PFCs, in the atmosphere. Among others, $N_2O$ is well known as an important greenhouse gas accounting for 7.9% of the total greenhouse effect and the effect of its emission is 310 times greater than that of $CO_2$. Agricultural $N_2O$ emissions are now thought to contribute to about 60% of the global anthropogenic $N_2O$ emission, which have been increased primarily due to fertilizer N consumption and manure management. Therefore, the reduction of $N_2O$ emissions in agriculture is being required. This study was conducted to determine the variation of $N_2O$ emissions by no-tillage (NT) and conventional tillage (CT) practices in the cultivation of soybean from the sandy loam soils under the different kinds of fertilizer treatments June through September 2016 in Cheong-ju, Republic of Korea. An experimental plot, located in the temperate climate zone, was composed of two main plots that were NT and CT, and were divided into four plots, respectively, in accordance with types of fertilizers (chemical fertilizer, liquid pig manure, hairy vetch and non-fertilizer). Among all the treatments, $N_2O$ emission was the highest in August and the lowest in June. When $N_2O$ emissions were evaluated during the growing season (June to September) in all fertilizer treatments, NT with hairy vetch treatment emitted the highest $N_2O$ emission in August, whereas, $N_2O$ emissions was the lowest in NT with non-fertilizer treatment in June, respectively (p = 0.05). Based on the cumulative amount of $N_2O$ emissions during the growing season of soybean, NT had lower $N_2O$ emission than CT by 0.01 - 0.02 kg $N_2O$, although NT had higher $N_2O$ emission than CT by 0.03 kg $N_2O$ in only the chemical fertilizer treatments. As a result, it seems that the applications of liquid pig manure and hairy vetch rather than chemical fertilizer could decrease the $N_2O$ emission in NT, compared to CT.

• Korean Journal of Animal Reproduction
• /
• v.27 no.4
• /
• pp.339-347
• /
• 2003

The purpose of this study was to investigate the development of bovine nuclear transfer (NT) embryos cultured in serum-free conditions. Bovine NT embryos cultured in various culture conditions were compared blastocyst development, total cell number and apoptosis using TUNEL assay. In experiment 1, blastocyst rates of NT embryos were significantly higher (P<0.01) in FBS (22.0％) and BSA (26.6％) groups than in PVA (6.3％) group. Total cell number was significantly higher in FBS (78.4$\pm$19.4) and BSA (90.9$\pm$29.1) groups than in PVA group (46.0$\pm$0.0). Apoptotic cell number was significantly fewer in FBS (3.1$\pm$1.4) and BSA (1.7$\pm$1.4) groups than in PVA group (7.0$\pm$20.0) However, all of results were not different between the FBS and BSA group. In experiment 2, blastocyst rates of NT embryos were significantly higher (P<0.05) in fatty acid free-BSA (FAF-BSA) group (26.8％) than in fraction V-BSA group (11.2％). Total cell number were somewhat higher in FAF-BSA group (89.8$\pm$30.7) than in fraction V-BSA group (88.1$\pm$19.3). Apoptotic cell number were somewhat fewer in FAF-BSA (1.7$\pm$1.5) group than in fraction V-BSA group (4.2$\pm$2.9). These findings suggest that serum free condition were effective for the in vitro development of bovine NT embryos. Therefore, we concluded that fatty acid free-BSA has beneficial effect in development bovine NT embryos and can be use as a serum substitute.

• Korean Journal of Materials Research
• /
• v.14 no.11
• /
• pp.764-768
• /
• 2004

Perovskite Pb(Mn_{1/3}Sbu_{2/3})O_2-Pb(Zr,Ti)O_3\;(PMS-PZT) was prepared and ZnO doping effects on its piezoelectric properties were investigated. Pyrochlore phase was not identified in the PMS-PZT ceramics with $0\sim5\;mol\%$ ZnO sintered at $1100^{\circ}C$ for 2 hrs, and maximum sintered density of $7.92 g/cm^3$ was obtained. Piezoelectric charge constant and voltage constant increased to $359{\times}10^{-12}\;C/N\;and\;22.5{\times}10^{-13}\;Vm/N$, respectively, with increasing ZnO content. Mechanical quality factor reduced considerably with increasing ZnO content. When the ZnO content was 3 $mol\%$, electromechanical coupling factor and relative dielectric constant showed maximum values of $56\%$ and 1727, respectively. This should be evaluated by complicated variations of sintered density, tetragonality of lattice, grain size, and A-site vacancy generated by ZnO addition and $Zn^{2+}$ substitution.

• The Journal of Korean Physical Therapy
• /
• v.16 no.2
• /
• pp.63-71
• /
• 2004

Denervated skeletal muscle produces muscle atrophy as well as changes at the neuromuscular junction which leads to terminal axonal sprouting and an ultrastructural remodeling. NT-3 is expressed in adult muscle and motoneurons. Normally NT-3 has a potential role in regulating adult neuromuscular jungtion and recovering following muscle atrophy. Also, it could influence synaptic neurotransmission between motoneurons and skeletal muscle cells. The purpose of this study was to investigate the effect of electrical stimulation therapy(EST) on NT-3 expression in neuromuscular junction following sciatic nerve transsection in rats. After EST application during 7 days, the immunoreactivity of NT-3 was increased in neuromuscular junction

• Journal of Food Hygiene and Safety
• /
• v.31 no.2
• /
• pp.74-84
• /
• 2016

Literacy on food additives of elementary school teachers (ET) and nutrition teachers (NT) could be influential factor on safe dietary education for school children. Therefore, the perceptions and information needs on food additives were surveyed from 351 elementary school teachers and nutrition teachers in metropolitan area of Korea, and the basic data for the promotion of risk communication on food additives among them were obtained. Compared to ET who consider 'taste' (39.1%) as the most important factor while purchasing food, NT considered 'safety' (68.1%) first (p < 0.001). Among the food labelling items, the level of understanding on food additives was the lowest both in ET (3.53) and NT (4.17), and NT showed better levels of understanding overall on food labels. Both ET and NT regarded hazardous factors of food as environmental pollutants, foodborne pathogens, and food additives in order, and tended to select 'no additives' or 'no artificial color' products while purchasing processed food. Although NT answered that they know all food additives had been passed the evaluation of safety and effectiveness tests (100%) and have standards of use (81.9%), majority of them (87.5%) believed the consumption of food additives are harmful on human health. ET (75.2%) also regarded food additives as dangerous materials. Above results suggested the necessity of proper and enough risk communication for both ET and NT. Both ET and NT wanted to have information on the safety or hazard of food additives. Most preferred media to get the information on food additives was TV (3.80) among ET and lecture (3.65) among NT. ET and NT trusted hospital, research institution/universities or the personnels working in these institutions as the provider of information on food additives. The result that the trust levels of ET and NT on government were relative low suggested the weakness of risk communication in Korean government. Although ET and NT answered that they do not trust mass media, their behaviors were affected by them such as reading food labels in ET (39.4%) and reducing the consumption of food additives in NT (50%). They also indicated mass media's problem of sensitive approach on food additives and asked the urgent reaction of government by providing sound information through experts on food additives. Above results revealed that ET and NT have different perceptions and information needs on food additives, therefore, proper risk communication should be provided for them to serve as dietary educators for elementary school children.

• Journal of the East Asian Society of Dietary Life
• /
• v.15 no.2
• /
• pp.194-199
• /
• 2005

This study was conducted to investigate the effect of blanching on the quality characteristics of dandelion Kimchi. Experimental groups were divided BT-group (dandelion was blanched in the $3\%$ brine for 15 seconds at $100^{\circ}C$, then salted in $8\%$ brine for 5 hours) and NT-group (dandelion was salted at $8\%$ brine for 5 hours). Changes in pH, acidity, color, number of total microbe and lactic acid bacteria, antioxidant activity and sensory quality were investigated during the fermentation at $10^{\circ}C$. The pH of the BT- and NT-Kimchi maintained higher than 4.1 for 21-days fermentation, but that of BT-Kimchi was lower than that of NT-Kimchi. And also, the titrable acidity of BT-Kimchi was maintained higher than that of NT-Kimchi. $L^\ast\;value\;and\;b^\ast$ value of BT-Kimchi were higher, while $a^\ast$ value of BT-Kimchi was lower than that of NT-Kimchi. There was no significantly difference in total microbial count between BT- and NT-Kimchi, while number of the lactic acid bacteria in the BT-Kimchi was higher than that of BT-Kimchi. There was no significant difference in the antioxidant activity between BT- and NT-group during the fermentation. In the results of sensory evaluation of the dandelion Kimchi, toughness, color, flavor and overall quality were good in the BT-Kimchi, while the bitter taste showed relatively strong in the NT-Kimchi.