• Nano
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• v.13 no.11
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• pp.1850131.1-1850131.19
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• 2018

In this paper, an electrochemical sensor for epinephrine (EP), a neurotransmitter was developed by anchoring molecularly imprinted polymeric matrix (MIP) on the surface of gold-coated quartz crystal electrode of electrochemical quartz crystal microbalance (EQCM) using starch nanoparticles (Starch NP) - reduced graphene oxide (RGO) nanocomposite as polymeric format for the first time. Use of EP in therapeutic treatment requires proper dose and route of administration. Proper follow-up of neurological disorders and timely diagnosis of them has been found to depend on EP level. The MIP sensor was developed by electrodeposition of starch NP-RGO composite on EQCM electrode in presence of template EP. As the imprinted sites are located on the surface, high specific surface area enables good accessibility and high binding affinity to template molecule. Differential pulse voltammetry (DPV) and piezoelectrogravimmetry were used for monitoring binding/release, rebinding of template to imprinted cavities. MIP-coated EQCM electrode were characterized by contact angle measurements, AFM images, piezoelectric responses including viscoelasticity of imprinted films, and other voltammetric measurements including direct (DPV) and indirect (using a redox probe) measurements. Selectivity was assessed by imprinting factor (IF) as high as 3.26 (DPV) and 3.88 (EQCM). Sensor was rigorously checked for selectivity in presence of other structurally close analogues, real matrix (blood plasma), reproducibility, repeatability, etc. Under optimized conditions, the EQCM-MIP sensor showed linear dynamic ranges ($1-10{\mu}M$). The limit of detection 40 ppb (DPV) and 290 ppb (EQCM) was achieved without any cross reactivity and matrix effect indicating high sensitivity and selectivity for EP. Hence, an eco-friendly MIP-sensor with high sensitivity and good selectivity was fabricated which could be applied in "real" matrices in a facile manner.

• Earthquakes and Structures
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• v.17 no.2
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• pp.143-162
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• 2019

Motivated by a simpler and more compact hybrid active tuned mass damper (ATMD) system with wide frequency spacing (i.e., high robustness) but not reducing the effectiveness using the least number of ATMD units, the active tuned tandem mass dampers (ATTMD) have been proposed to attenuate undesirable oscillations of structures under the ground acceleration. Likewise, it is expected that the frequency spacing of the ATTMD is comparable to that of the active multiple tuned mass dampers (AMTMD) or the multiple tuned mass dampers (MTMD). In accordance with the mode generalised system in the specific vibration mode being controlled (simply referred herein to as the structure), the closed-form expression of the dimensionless displacement variances has been derived for the structure with the attached ATTMD. The criterion for the optimum searching may then be determined as minimization of the dimensionless displacement variances. Employing the gradient-based optimization technique, the effects of varying key parameters on the performance of the ATTMD have been scrutinized in order to probe into its superiority. Meanwhile, for the purpose of a systematic comparison, the optimum results of two active tuned mass dampers (two ATMDs), two tuned mass dampers (two TMDs) without the linking damper, and the TTMD are included into consideration. Subsequent to work in the frequency domain, a real-time Simulink implementation of dynamic analysis of the structure with the ATTMD under earthquakes is carried out to verify the findings of effectiveness and stroke in the frequency domain. Results clearly show that the findings in the time domain support the ones in the frequency domain. The whole work demonstrates that ATTMD outperforms two ATMDs, two TMDs, and TTMD. Thereinto, a wide frequency spacing feature of the ATTMD is its highlight, thus deeming it a high robustness control device. Furthermore, the ATTMD system only needs the linking dashpot, thus embodying its simplicity.

• Parasites, Hosts and Diseases
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• v.59 no.2
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• pp.167-171
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• 2021

Haemonchosis remains a significant problem in small ruminants. In this study, the assay of recombinase polymerase amplification (RPA) combined with the lateral flow strip (LFS-RPA) was established for the rapid detection of Haemonchus contortus in goat feces. The assay used primers and a probe targeting a specific sequence in the ITS-2 gene. We compared the performance of the LFS-RPA assay to a PCR assay. The LFS-RPA had a detection limit of 10 fg DNA, which was 10 times less compared to the lowest detection limit obtained by PCR. Out of 24 goat fecal samples, LFS-RPA assay detected H. contortus DNA with 95.8% sensitivity, compared to PCR, 79.1% sensitivity. LFS-RPA assay did not detect DNA from other related helminth species and demonstrated an adequate tolerance to inhibitors present in the goat feces. Taken together, our results suggest that LFS-RPA assay had a high diagnostic accuracy for the rapid detection of H. contortus and merits further evaluation.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.8 no.2
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• pp.63-70
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• 2022

The development of myocardial perfusion imaging (MPI) agents has been motivated because coronary artery disease has been one of the leading causes of death worldwide since the 1960s. Several positron emission tomography (PET) MPI agents were developed, and ¹⁸F-labeled phosphonium cations were reported actively among them. In this study, we synthesized novel ¹⁸F-labeled phosphonium cations, (5-[¹⁸F]fluoropentyl)diphenyl(pyridin-2-yl)phosphonium and (2-(2-[¹⁸F]fluoroethoxy)ethyl)diphenyl(pyridin-2-yl)phosphonium, and evaluated potential as MPI agents. Two labeled compounds were synthesized via nucleophilic substitution reactions of ¹⁸F-fluoride with the appropriate tosylate precursor in the presence of Kryptofix 2.2.2 and K₂CO₃. MicroPET studies were performed in normal rats to evaluate in vivo distribution of radiolabeled phosphonium cations for 60 min. The radiolabeled compounds were synthesized with 5%-10% yield. The radiochemical purity of labeled compounds was > 98% by analytical HPLC, and the specific activity was > 11.8 GBq/µmol. The result of microPET studies of these labeled compounds in rats showed intense uptake in the myocardium at 30 and 60 min. The results suggest that these ¹⁸F-labeled novel phosphonium cations would have potential as promising candidates for myocardial perfusion imaging.

• Journal of Ginseng Research
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• v.48 no.1
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• pp.103-111
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• 2024

Background: Ginseng (Panax ginseng Mayer) is an important natural medicine. However, a long culture period and challenging quality control requirements limit its further use. Although artificial cultivation can yield a sustainable medicinal supply, research on the association between the transplantation and chaining of metabolic networks, especially the regulation of ginsenoside biosynthetic pathways, is limited. Methods: Herein, we performed Liquid chromatography tandem mass spectrometry based metabolomic measurements to evaluate ginsenoside accumulation and categorise differentially abundant metabolites (DAMs). Transcriptome measurements using an Illumina Platform were then conducted to probe the landscape of genetic alterations in ginseng at various ages in transplantation mode. Using pathway data and crosstalk DAMs obtained by MapMan, we constructed a metabolic profile of transplantation Ginseng. Results: Accumulation of active ingredients was not obvious during the first 4 years (in the field), but following transplantation, the ginsenoside content increased significantly from 6-8 years (in the wild). Glycerolipid metabolism and Glycerophospholipid metabolism were the most significant metabolic pathways, as Lipids and lipid-like molecule affected the yield of ginsenosides. Starch and sucrose were the most active metabolic pathways during transplantation Ginseng growth. Conclusion: This study expands our understanding of metabolic network features and the accumulation of specific compounds during different growth stages of this perennial herbaceous plant when growing in transplantation mode. The findings provide a basis for selecting the optimal transplanting time.

• Journal of Genetic Medicine
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• v.21 no.1
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• pp.22-30
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• 2024

Purpose: Neurofibromatosis 1 (NF1) is one of the most common autosomal dominant diseases caused by heterozygous mutation in the NF1 gene. Mutation detection is complex owing to the large size of the NF1 gene, the presence of a high number of partial pseudogenes, and the great variety of mutations. We aimed to study the mutation spectrum of NF1 gene in Korean patients with NF1. Materials and Methods: We have analyzed total 69 unrelated patients who were clinically diagnosed with NF1. PCR and sequencing of the NF1 gene was performed in all unrelated index patients. Additionally, multiplex ligation-dependent probe amplification (MLPA) test of the NF1 and SPRED1 gene analysis (sequencing and MLPA test) were performed in patients with negative results from NF1 gene sequencing analysis. Results: Fifty-five different variants were identified in 60 individuals, including six novel variants. The mutations included 36 single base substitutions (15 missense and 21 nonsense), eight splicing mutations, 13 small insertion or deletions, and three gross deletions. Most pathogenic variants were unique. The mutations were evenly distributed across exon one through 58 of NF1, and no mutational hot spots were found. When fulfilling the National Institutes of Health criterion for the clinical diagnosis of NF1, the detection rate was 84.1%. Cafe-au-lait macules were observed in all patients with NF1 mutations. There is no clear relationship between specific mutations and clinical features. Conclusion: This study revealed a wide spectrum and genetic basis of patients with NF1 in Korea. Our results aim to contribute genetic management and counseling.

• Journal of Radiation Protection and Research
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• v.25 no.4
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• pp.223-232
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• 2000

Comparative study was performed for the assessment of DNA damage and Chromosomal aberration in human lymphocyte exposed to low dose radiation using fluorescence in situ hybridization(FISH) and single cell gel electrophoresis(SCGE). Chromosomal aberrations in human lymphocytes exposed to radiation at doses of 5, 10, 30 and 50cGy were analysed with whole chromosome-specific probes by human chromosome 1, 2 and 4 according to PAINT system. FISH with chromosome-specific probe has been used to be a valid and rapid method fer detection of chromosome rearrangements induced by low dose radiation. The frequencies of stable translocation per cell equivalents were 0.0116, 0.0375, 0.040f, 0.0727 and 0.0814 for 0, 5, 10, 30 and 50cGy, respectively, and those of dicentric were 0.00, 0.0125, 0.174, 0.0291 and 0.0407 respectively. Radiation induced DNA damage in human lymphocyte in a dose-dependent manner at low doses from 5cGy to 50cGy, which were analysed by single tell gel electrophoresis(SCGE). From above results, FISH seemed to be useful for radiation biodosimetry by which the frequencies of stable aberrations in human lymphocyte can be observed more easily than by conventional method and SCGE also seemed to be sensitive method f9r detecting DNA damage by low dose radiation exposure, so that those methods will improve our technique to perform meaningful biodosimetry for radiation at low doses.

• Journal of Life Science
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• v.26 no.8
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• pp.875-880
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• 2016

The plasma membrane plays a crucial role in relaying signals from the outside environment to the inside of the cells. In eukaryotic cells, the inner leaflets of the plasma membrane are composed mostly of phospholipids, including phosphatidylethanolamine (PE), phosphatidylserine (PS), and phosphatidylinositides (PIs). In this study, we tried to analyze the morphological changes induced by EGFP-fused membrane binding proteins, which are targeted to the plasma membrane via specific phospholipids binding. As a result, we found that overexpression of EGFP-P4M-SidM, a specific PI4P binding protein, or EGFP alone, did not induce any morphological changes. On the other hand, overexpression of EGFP-PLCδ1(PH), which is a specific PI(4,5)P₂ binding protein, EGFP-AKT1(PH) which binds to PI(3,4,5)P₃, or EGFP-OSH2(PH)×2 which binds to PI4P and PI(4,5)P₂, could induce the filopodia and lamilapodia formation as well as cell shrinkage. Overexpression of Lact-C2-EGFP which is a specific PS-binding probe, EGFP fused Aplysia phosphodiesterase 4 (ApPDE4) long-form (L(N20)-EGFP) which is localized to the plasma membrane via hydrophobic interaction, or EGFP fused Aplysia PDE4 short-form (S(N-UCR1-2)-EGFP) which is localized to the plasma membrane via electrostatic interaction, could induce cell shrinkage, but not filopodia or lamilapodia formation. Taken together, our data support that the different phospholipid bindings in the plasma membrane could induce different characteristic morphological changes. Thus, we can analyze, characterize, and classify the cellular morphological changes induced by the various phospholipid binding proteins.

• Research in Plant Disease
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• v.17 no.3
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• pp.358-363
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• 2011

Dapple fruits of plum cv. Oiishiwase (Prunus salicina L.) were occurred at Gyeonggi-do and Gyeongsangbukdo. The symptoms resembled the dapple fruit disease caused by Hop stunt viroid (HSVd). To identify the causal disease agents, RT-PCR was performed with the specific primers of HSVd. RT-PCR analysis showed that HSVd variants (DP1, DP2) were detected from dapple fruits. HSVd detection was also confirmed by the dot blot hybridization using a DIG-probe specific to HSVd. Nucleotide sequences of DP1 and DP2 had the identities of 94-100% with those of other 7 variants of HSVd in Genbank database. DP1 and DP2 were different in two nucleotides of CG and AA at position of 59 and 60, orderly. Based on nucleotide sequences at position of 59 and 60, HSVd variants associated with plum dapple fruits could be divided mainly into three groups as CG, AA and TG.

• IMMUNE NETWORK
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• v.3 no.2
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• pp.103-109
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• 2003

Background: As all HLA class II genes, the DQ genes show their polymorphic variation mainly in the second exon, which encodes the first extracellular domain of the molecule. PCR-SSOP (Polymerase chain reaction-Sequence specific oligonucleotide probe) techniques were frequently used for HLA-DQA1 and DQB1 typing but certain alleles, $DQA1^*0101/0104/0105$, $^*302/0303$, $*0501/0505$ and $DQB1^*0201/^*0202$ which differ from each other in segment other than exon 2, could not be unequivocally assigned. Methods: To overcome this problem, we applied additional PCR-SSP (PCR-Sequence specific primer) method to analyze DQA1 exons 1, 3 and 4 and DQB1 exon 3. And we investigated the distributions and haplotypes of HLA-DRB1, DQA1 and DQB1 alleles in 406 unrelated Korean healthy individuals. Results: Using this method the indistinguishable alleles of DQA1 and DQB1 in PCR-SSOP were typed definitively. We also found several important associations between DQA1 and DQB1 alleles in the Korean population; $DQA1^*0101-DQB1^*0501$, $DQA1^*0104-DQB1^*0502$ or $-^*0503$, $DQA1^*0105-DQB1^*0501$, $DQA1^*0302-DQB1^*0303$, $DQA1^*0303-DQB1^*0401$ or $-^*0402$, $DQA1^*0501-DQB1^*0201$, $DQA1^*0505-DQB1^*0301$, and $DQA1^*0201-DQB1^*0202$. The haplotypes of DRB1-DQA1-DQB1 associated with $DQA1^*01$, $^*03$, $^*05$, and $DQB1^*02$ subtypes were investigated. Several haplotypes associated with these alleles were observed in the Korean population. Conclusion: Our results can be helpful to find potential unrelated donors for bone marrow registries and study the HLA-associated disease and anthropology at high-resolution allelic level.