• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.11
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• pp.15-22
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• 2016

In satellite communication, transmission performance is degraded due to long propagation delay and relatively high data loss compared to terrestrial network. In this paper, We propose Hybrid TCP PEP scheme with XOR coding and Hybla TCP, which reduces the transmission performance degradation due to the transmission delay time. Experimental results show that the proposed method improves the file transfer rate by more than 10% in the environment with high channel error rate. Therefore, Hybrid TCP, which is a mixture of XOR coding method and TCP Hybla, is considered to contribute to the improvement of transmission speed in satellite communication when applied to connection split PEP.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.1
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• pp.58-65
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• 2016

Satellite communication is a wide area network (WAN) which provides communication service worldwide. However, the performance of TCP can be seriously degraded in the satellite networks due to limited bandwidth, long round-trip time (RTT) and high bit error rate (BER) over satellite links. In order to improve the performance of TCP, this paper proposes cross-layer Performance Enhancing Proxy (PEP) in digital video broadcasting-return channel via satellite (DVB-RCS) networks. The proposed protocol sets TCP Congestion Window (CWND) size by using satellite resource allocation information exchanged between TCP and the link-layer. we implement PEP testbed based on Linux to evaluate the performance of the proposed protocol. The simulation results show that the proposed protocol performs better than standard TCP both in single and multiple sessions in variant BER, because the proposed protocol sets TCP CWND size by using satellite resource allocation.

• Journal of Microbiology and Biotechnology
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• v.16 no.3
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• pp.457-464
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• 2006

Three extracellular proteases (Vpr, peptidase T, and subtilisin) were identified from the culture supernatant of Bacillus subtilis KCTC 3014. All the proteins were partially purified as a mature form by using a DEAE-cellulose ion-exchange column chromatography. Their activities were determined by using zymography and densitometry. The relative molecular masses of Vpr and peptidase T (PepT) were determined to be 68 and 48 kDa by SDS-PAGE and zymography, respectively. However, subtilisin formed a 'binding mode' at the top of the separating gel. After denaturation by boiling at $100^{\circ}C$ for 5 min, its molecular mass was determined to be 29 kDa, whereas its activity was lost. The optimal pH of Vpr, PepT, and subtilisin were 9.0, 6.0-7.0, and 7.0-8.0, respectively. The optimal temperature of Vpr, PepT, and subtilisin was 40, 50, and $40^{\circ}C$, respectively. Inhibitor test revealed that Vpr and subtilisin were serine proteases and that PepT was a metalloprotease. Interestingly, we found that Vpr showed no enzyme activity on a 2DE zymogram gel. Three genes, vpr, pepT, and apr (encoding subtilisin protein), were cloned and their nucleotide and deduced amino acid sequences were determined.

• The Plant Pathology Journal
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• v.24 no.2
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• pp.152-158
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• 2008

A peculiar virus-like disease of tomato showing yellow mosaic and necrotic spots on leaves and necrosis on veins, petioles and stems was observed at the Tomato Experimental Station (TES), Buyeo, Chungcheongnamdo, Korea. The disease incidence at TES fields ranged from 21 to 35% infecting different tomato cultivars. For this reason, to identify the virus infecting tomato and to characterize the virus based on biology, serology, cytology and at molecular level. Here, leaf samples were randomly collected from different infected tomato cultivars at TES fields and greenhouses and tested by ELISA using Pepper mottle virus (PePMoV) and Tomato mosaic virus (ToMV) antisera. Infected saps were mechanically inoculated in different host plants to test for pathogenicity, symptomatology and host ranges. Infected tissues and ultrathin sections were examined by electron microscopy. Finally, putative coat protein and 3'-untranslated region (CP/3'-UTR) fragment was amplified and cloned for sequence determination and analyzed its genetic relationship to existing PepMoV and PVY sequences at the Genbank. Results showed 69% of the samples were positive with PepMoV, 13% with ToMV and 19 % were doubly infected with PepMoV and ToMV. Symptoms greatly varied from different host plants inoculated with tomato leaf sap infected with PepMoV alone and discussed in detailed in this paper. Electron microscopy from infected tissues showed filamentous particles of 720-750nm in length, a typical morphology and size of PepMoV. In addition, cylindrical inclusion bodies, pinwheels, scrolls and laminates with masses of fibrillar inclusions were also found in ultrathin sections. Alignment of the sequences of the CP/3'-UTR revealed >96% sequence identity with PepMoV and only <61% with PVY. Taken together, all these evidences presented clearly indicated that the causal agent infecting tomato at TES was PepMoV and we designated this PepMoV infecting tomato as Tom-sd2 strain in this study.

• Journal of Preventive Medicine and Public Health
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• v.50 no.3
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• pp.210-216
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• 2017

Objectives: One way to prevent deaths due to rabies is the timely utilization of post-exposure prophylaxis (PEP). Therefore, in addition to an understanding of the epidemiological distribution of animal bites, it is necessary to explore the factors leading to delays in PEP initiation. Methods: This cross-sectional study was conducted in Iran in 2011, and included 7097 cases of animal bites recorded at the Rabies Treatment Center of the Shiraz University of Medical Sciences using the census method. Logistic regression was used to identify factors associated with delays in PEP. Results: Among the patients studied, 5387 (75.9%) were males. The prevalence of animal bites in Fars province was 154.4 per 100 000 people. Dogs were the most frequent source of exposure (67.1%), and the most common bitten part of the body was the hands (45.5%). A delay in the initiation of PEP was found among 6.8% of the studied subjects. This delay was more likely in housewives (odds ratio [OR], 4.66; 95% confidence interval [CI], 2.12 to 10.23) and less likely in people with deep wounds (OR, 0.65; 95% CI, 0.43 to 0.97). Conclusions: Although all animal bite victims received complete PEP, in some cases, there were delays. Further, the type of animal involved, the depth of the bite, and the patient's occupation were the major factors associated with a delay in the initiation of PEP for rabies prevention.

• Clinical Endoscopy
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• v.56 no.2
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• pp.214-220
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• 2023

Background/Aims: This study aimed to determine whether vitamin C in addition to indomethacin decreases the occurrence and severity of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) occurrence and severity. Methods: This randomized clinical trial included patients undergoing ERCP. The participants were administered either rectal indomethacin (100 mg) plus an injection of vitamin C (500 mg) or rectal indomethacin (100 mg) alone just before ERCP. The primary outcomes were PEP occurrence and severity. The secondary amylase and lipase levels were determined after 24 hours. Results: A total of 344 patients completed the study. Based on intention-to-treat analysis, the PEP rates were 9.9% for indomethacin plus vitamin C plus indomethacin and 15.7% for indomethacin alone. Regarding the per-protocol analysis, the PEP rates were 9.7% and 15.7% in the combination and indomethacin arms, respectively. There was a remarkable difference between the two arms in PEP occurrence and severity on intention-to-treat and per-protocol analyses (p=0.034 and p=0.031, respectively). The post-ERCP lipase and amylase concentrations were lower in the combination arm than in the indomethacin alone arm (p=0.034 and p=0.029, respectively). Conclusions: Vitamin C injection in addition to rectal indomethacin reduced PEP occurrence and severity.

• BMB Reports
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• v.41 no.5
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• pp.408-413
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• 2008

Pyridoxal-5'-phosphate phosphatase (PLPP) catalyzes the dephosphorylation of pyridoxal-5'-phosphate (PLP). A human brain PLPP gene was fused with a PEP-1 peptide and produced a genetic in-frame PEP-1-PLPP fusion protein. The purified PEP-1-PLPP fusion protein was efficiently transduced into PC12 cells in a time- and dose-dependent manner when added exogenously to culture media. Once inside the cells, the transduced PEP-1-PLPP fusion protein was stable for 36 h. The concentration of PLP was markedly decreased by the addition of exogenous PEP-1-PLPP to media pretreated with the vitamin $B_6$ precursors; pyridoxine, pyridoxal kinase and pyridoxine-5'-phosphate oxidase into cells. The results suggest that the transduction of the PEP-1-PLPP fusion protein can be one mode of PLP level regulation, and to replenish this enzyme in the various neurological disorders related to vitamin $B_6$.

• BMB Reports
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• v.44 no.5
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• pp.329-334
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• 2011

Many proteins with poor transduction efficiency were reported to be delivered to cells by fusion with protein transduction domains (PTDs). In this study, we investigated the effect of levosulpiride on the transduction of PEP-1 ribosomal protein S3 (PEP-1-rpS3), and examined its influence on the stimulation of the therapeutic properties of PEP-1-rpS3. PEP-1-rpS3 transduction into HaCaT human keratinocytes and mouse skin was stimulated by levosulpiride in a manner that did not directly affect the cell viability. Following 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation in mice, levosulpiride alone was ineffective in reducing TPA-induced edema and in inhibiting the elevated productions of inflammatory mediators and cytokines, such as cyclooxygenase-2, inducible nitric oxide synthase, interleukin-6 and -1${\beta}$, and tumor necrosis factor-${\alpha}$. Anti-inflammatory activity by PEP-1-rpS3 + levosulpiride was significantly more potent than by PEP-1-rpS3 alone. These results suggest that levosulpiride may be useful for enhancing the therapeutic effect of PEP-1-rpS3 against various inflammatory diseases.

• Clinical Endoscopy
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• v.57 no.2
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• pp.226-236
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• 2024

Background/Aims: This study aimed to compare the safety of the double-guidewire technique (DGT) with that of the conventional single-guidewire technique (SGT) in real-world situations. Methods: A total of 240 patients with naïve papilla who underwent endoscopic retrograde cholangiopancreatography (ERCP) at Daegu Catholic University Medical Center between January 2021 and December 2021 were included. The primary outcome was the rate of post-ERCP pancreatitis (PEP) in the SGT and DGT groups. Results: A total of 163 patients (67.9%) belonged to the SGT group, and 77 (32.1%) belonged to the DGT group. The rates of successful biliary cannulation were 95.7% and 83.1% in the SGT and DGT groups, respectively (p=0.002). In the study group, PEP occurred in 14 patients (5.8%). The PEP rates were not significantly different between the SGT and DGT groups (4.3% vs. 9.1%, p=0.150). In the multivariate analysis, the age of <50 years (odds ratio [OR], 9.305; 95% confidence interval [CI], 1.367-63.358; p=0.023) and hyperlipidemia (OR, 7.384; 95% CI, 1.103-49.424; p=0.039) were significant risk factors for PEP in the DGT group. Conclusions: DGT did not increase the PEP rate in patients with naïve papilla. In addition, the age of <50 years and hyperlipidemia were significant risk factors for PEP in the DGT group.

• BMB Reports
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• v.40 no.2
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• pp.189-195
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• 2007

Although the incidence and severity of atopic dermatitis (AD) is steadily increasing at an alarming rate, its pathogenic mechanisms remain poorly understood yet. Recently, we found that the expression of Grb7 protein was markedly decreased in AD patients using proteomic analysis. In the present study, human Grb7 gene was fused with PEP-1 peptide in a bacterial expression vector to produce a genetic in-frame PEP-1-Grb7 fusion protein. The expressed and purified PEP-1-Grb7 fusion proteins transduced efficiently into skin cells in a time- and dose-dependent manner when added exogenously in culture media. Once inside the cells, the transduced PEP-1-Grb7 protein was stable for 48 h. In addition, transduced PEP-1-Grb7 fusion protein markedly increased cell viability in macrophage RAW 264.7 cells treated with LPS by inhibition of the COX-2 expression level. These results suggest that the PEP-1-Grb7 fusion protein can be used in protein therapy for inflammatory skin disorders, including AD.