• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.25 no.2
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• pp.483-499
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• 1995

Mandibular first molars of the rats were undertaken to observe the radiosensitivity of amelogenesis. Twenty four Sprague-Dawley rats received 396cGy radiation with the MK Cell irradiator using Cs-137, and twenty four rats served as control. They were devided into two groups; Group 1 which received radiation at the 14th day after gestation and group 2 which received radiation at the 19th day after gestation. Light Microscopy and Transmitted Electron Microscopy investigation was undertaken in the group 1 at the 15th, 18th, 20th, 22nd(2 days after birth), and 25th day(5 days after birth) after gestation, and in the group 2 at the 21th(birth day), 22nd(2 days after birth), and 25th(5 days after birth) day after gestation. The following histopathologic findings were obtained. 1. Compared with control group, experimental group showed a delayed formation of enamel and dentin due to slow rate of differentiation of undifferentiated mesenchymal cells. 2. In the experimental groups, the arrangement of the inner enamel epithelium was irregular and there were many vacuoles in the cytoplasm. There were dilated rER and mitochondria, increase of the intercellular space, and loss of the cellular polarity. 3. In the group 1, early enamel without Tomes' process, and early organic matrix was observed at the 25th day after gestation. 4. In the group 2, histopathologic changes were similar to those of the group 1, but the degree of changes was more severe than that of the group 1.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.8B
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• pp.1426-1437
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• 1999

The introduction of fast packet switching networks such as the ATM leads to the possibility of video services with constant quality. However, the fixed traffic descriptor(TD), which is defined by ATM Forum and ITU-T, can not simultaneously satisfy network efficiency and video quality. This paper presents fast resource reallocation protocol (FRRP) which can provide an effective compromise between network efficiency and video quality. This protocol reallocates the network resources and then adapts the traffic to the reallocated resources. In the proposed method, a video session is divided into several time-intervals according to its generated traffic and TD is calculated which well characterizes the traffic during the specific subdivided interval. In addition, a system model, where MPEG coding algorithm and network control are unified, is proposal and the performance of the FRRP in terms of cell loss rate(CLR) is evaluated though the simulation using real video traffic(Star Wars). Simulation results show that the FRRP has only 5 ~35% CLR of the fixed TD.

• Korean Journal of Medicinal Crop Science
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• v.25 no.6
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• pp.404-410
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• 2017

Background: Hair loss related syndromes are increasing due to environmental pollution and stress. Hair care products are mainly prepared by mixing chemicals and natural extracts, such as those obtained from medicinal plants. The purpose of this study was to investigate the effects of 70% ethanol extracts from the flowers of Calendula officinalis, fruit body of Phellinus linteus, and the whole plant of Houttuynia cordata on the growth of CCD-986 cells, hair follicle dermal papilla cells (HFDPC), and 3T3-L1 cells. Methods and Results: All sample extracts at all concentrations, except for that from P. linteus fruit body at $500{\mu}g/m{\ell}$, were cytotoxic to CCD-986 cells. However, none of the sample extracts were cytotoxic to HFDPC. The lipid differentiation of 3T3-L1 cells regulates hair regeneration via secretion of platelet derived growth factor. The 70% ethanol extract of H. cordata whole plant promoted hair growth. Adipogenesis rate significantly increased in a treatment concentration-dependent manner. Conclusions: These results suggest that 70% ethanol extracts of C. officinalis flower, P. linteus fruit body and H. cordata could be used for the development of hair care products.

• Journal of Korean Medicine for Obesity Research
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• v.19 no.1
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• pp.1-11
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• 2019

Objectives: The purpose of the present study was to evaluate the preventive effects of ethanol extract of Polygalae radix (EEPR) against oxidative stress (hydrogen peroxide, $H_2O_2$)-induced DNA damage and apoptosis in Chang liver cells. Methods: Chang liver cells were pretreated with various concentrations of EEPR and then challenged with 0.5 mM $H_2O_2$. The cell viability and apoptosis were assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and flow cytometry analysis, respectively. The levels of reactive oxygen species (ROS), mitochondrial membrane potentials (MMPs) and adenosine tri-phosphate (ATP) contents were measured. Expression levels of Bcl-2 and Bax were also determined using Western blot analysis. Results: The results showed that the decreased survival rate induced by $H_2O_2$ could be attributed to the induction of DNA damage and apoptosis accompanied by the increased production of ROS, which was remarkably protected by EEPR. In addition, the loss of $H_2O_2$-induced MMPs and ATP contents was significantly attenuated in the presence of EEPR. The inhibitory effect of EEPR on $H_2O_2$-induced apoptosis was associated with up-regulation of Bcl-2 and down-regulation of Bax, thus reducing the Bax/Bcl-2 ratio. Conclusions: Our data prove that EEPR protects Chang liver cells against $H_2O_2$-induced DNA damage and apoptosis by scavenging ROS and thus suppressing the mitochondrial-dependent apoptosis pathway.

• Journal of Gastric Cancer
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• v.19 no.1
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• pp.111-120
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• 2019

Background: Billroth I anastomosis is one of the most common reconstruction methods after distal gastrectomy for gastric cancer. Intracorporeal Billroth I (ICBI) anastomosis and extracorporeal Billroth I (ECBI) anastomosis are widely used in laparoscopic surgery. Here we compared ICBI and ECBI outcomes at a major gastric cancer center. Methods: We retrospectively analyzed data from 2,284 gastric cancer patients who underwent laparoscopic distal gastrectomy between 2009 and 2017. We divided the subjects into ECBI (n=1,681) and ICBI (n=603) groups, compared the patients' clinical characteristics and surgical and short-term outcomes, and performed risk factor analyses of postoperative complication development. Results: The ICBI group experienced shorter operation times, less blood loss, and shorter hospital stays than the ECBI group. There were no clinically significant intergroup differences in diet initiation. Changes in white blood cell counts and C-reactive protein levels were similar between groups. Grade II-IV surgical complication rates were 2.7% and 4.0% in the ECBI and ICBI groups, respectively, with no significant intergroup differences. Male sex and a body mass index (BMI) ${\geq}30$ were independent risk factors for surgical complication development. In the ECBI group, patients with a BMI ${\geq}30$ experienced a significantly higher surgical complication rate than those with a lower BMI, while no such difference was observed in the ICBI group. Conclusion: The surgical safety of ICBI was similar to that of ECBI. Although the chosen anastomotic technique was not a risk factor for surgical complications, ECBI was more vulnerable to surgical complications than ICBI in patients with a high BMI (${\geq}30$).

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.4
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• pp.1317-1341
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• 2021

Nowadays, the Internet of Things (IoT) is adopted to enable effective and smooth communication among different networks. In some specific application, the Wireless Sensor Networks (WSN) are used in IoT to gather peculiar data without the interaction of human. The WSNs are self-organizing in nature, so it mostly prefer multi-hop data forwarding. Thus to achieve better communication, a cross-layer routing strategy is preferred. In the cross-layer routing strategy, the routing processed through three layers such as transport, data link, and physical layer. Even though effective communication achieved via a cross-layer routing strategy, energy is another constraint in WSN assisted IoT. Cluster-based communication is one of the most used strategies for effectively preserving energy in WSN routing. This paper proposes a Bio-inspired cross-layer routing (BiHCLR) protocol to achieve effective and energy preserving routing in WSN assisted IoT. Initially, the deployed sensor nodes are arranged in the form of a grid as per the grid-based routing strategy. Then to enable energy preservation in BiHCLR, the fuzzy logic approach is executed to select the Cluster Head (CH) for every cell of the grid. Then a hybrid bio-inspired algorithm is used to select the routing path. The hybrid algorithm combines moth search and Salp Swarm optimization techniques. The performance of the proposed BiHCLR is evaluated based on the Quality of Service (QoS) analysis in terms of Packet loss, error bit rate, transmission delay, lifetime of network, buffer occupancy and throughput. Then these performances are validated based on comparison with conventional routing strategies like Fuzzy-rule-based Energy Efficient Clustering and Immune-Inspired Routing (FEEC-IIR), Neuro-Fuzzy- Emperor Penguin Optimization (NF-EPO), Fuzzy Reinforcement Learning-based Data Gathering (FRLDG) and Hierarchical Energy Efficient Data gathering (HEED). Ultimately the performance of the proposed BiHCLR outperforms all other conventional techniques.

• BMB Reports
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• v.55 no.7
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• pp.348-353
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• 2022

Gastrointestinal cancer is associated with a high mortality rate. Here, we report that the splice variant of NRP/B contributes to tumorigenic activity in highly malignant gastric cancer through dissociation from the tumor repressor, HDAC5. NRP/B mRNA expression is significantly higher in the human gastric cancer tissues than in the normal tissues. Further, high levels of both the NRP/B splice variant and Lgr5, but not the full-length protein, are found in highly tumorigenic gastric tumor cells, but not in non-tumorigenic cells. The loss of NRP/B markedly inhibits cell migration and invasion, which reduces tumor formation in vivo. Importantly, the inhibition of alternative splicing increases the levels of NRP/B-1 mRNA and protein in AGS cells. The ectopic expression of full-length NRP/B exhibits tumor-suppressive activity, whereas NRP/B-2 induces the noninvasive human gastric cancer cells tumorigenesis. The splice variant NRP/B-2 which loses the capacity to interact with tumor repressors promoted oncogenic activity, suggesting that the BTB/POZ domain in the N-terminus has a crucial role in the suppression of gastric cancer. Therefore, the regulation of alternative splicing of the NRP/B gene is a potential novel target for the treatment of gastrointestinal cancer.

• Clinical and Experimental Reproductive Medicine
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• v.49 no.1
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• pp.62-69
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• 2022

Objective: This study aimed to describe a distinct subpopulation of azoospermic patients with isolated elevation of follicle-stimulating hormone (iFSH) and poor outcomes of microdissection testicular sperm extraction (microTESE). Methods: A retrospective analysis of microTESE outcomes was conducted among 565 patients with non-obstructive azoospermia (NOA). Testicular pathology was assessed by the dominant histological pattern and Bergmann-Kliesch score (BKS). Descriptive statistics were presented for the iFSH subgroup. Inhibin B levels, the sperm retrieval rate (SRR), and BKS were compared in iFSH patients and other NOA patients. Results: The overall SRR was 33.3% per microTESE attempt. The median BKS was 0.6 (interquartile range, 0-2). Of all NOA patients, 132 had iFSH, and microTESE was successful only in 11 of those cases, with an SRR of 8.3%, while the total SRR in other NOA patients was 38.1% (p<0.001). iFSH had a sensitivity of 32.1% (95% confidence interval [CI], 27.4%-36.8%) and specificity of 94.1% (95% CI, 90.8-97.5%) as a predictor of negative microTESE outcomes. Conclusion: Patients with iFSH may harbor a distinct testicular phenotype with total loss of the germ cell population and poor outcomes of surgical sperm retrieval.

• Journal of Animal Science and Technology
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• v.64 no.4
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• pp.707-716
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• 2022

The core intention to undertake this experiment for a period of 21 days is to evaluate the effect of salicylic acid (SA) supplemented diet on the performance and blood metabolites of sows and their litters. Sows weighing 208.5 ± 18.34kg and their neonates were used. From day 114 of gestation to 21st day of lactation(weaning), ten multiparous sows (n = 5/treatment) (Landrace × Yorkshire) were assigned randomly into one of two treatments: CON (basal diet) and TRT (CON + 0.05% SA). There was no significant difference in the body weight, backfat thickness, backfat loss, and body condition score in SA treated sows compared to sows fed the CON diet. However, the bodyweight of sow was dramatically reduced by an average of 16kg from farrowing to weaning time. The dietary inclusion of SA in the sow diet slightly improved the survival rate (p = 0.065) and showed a higher body weight (p = 0.009) in piglets. However, there was no significant difference in red blood cell, Fe, Hematocrit, and Hb concentrations between CON and TRT sows' groups, but the total iron-binding capacity (TIBC) was significantly reduced in sows from the TRT group compared with the CON group from the beginning to weaning. The outcome of this trial shows that dietary addition of SA on sows diet from early lactation could increase the birth weight and TIBC of neonates at the end of the trial.

• IMMUNE NETWORK
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• v.21 no.1
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• pp.8.1-8.17
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• 2021

The global crisis caused by the coronavirus disease 2019 (COVID-19) led to the most significant economic loss and human deaths after World War II. The pathogen causing this disease is a novel virus called the severe acute respiratory syndrome coronavirus 2 (SARSCoV-2). As of December 2020, there have been 80.2 million confirmed patients, and the mortality rate is known as 2.16% globally. A strategy to protect a host from SARS-CoV-2 is by suppressing intracellular viral replication or preventing viral entry. We focused on the spike glycoprotein that is responsible for the entry of SARS-CoV-2 into the host cell. Recently, the US Food and Drug Administration/EU Medicines Agency authorized a vaccine and antibody to treat COVID-19 patients by emergency use approval in the absence of long-term clinical trials. Both commercial and academic efforts to develop preventive and therapeutic agents continue all over the world. In this review, we present a perspective on current reports about the spike glycoprotein of SARS-CoV-2 as a therapeutic target.