• Microbiology and Biotechnology Letters
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• v.32 no.1
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• pp.11-15
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• 2004

Embryonic stem (ES) cells are derived from the inner cell mass of the blastocyst-stage embryos that can be propagated indefinitely and, at the same time, can be differentiated into all the cell types that constitute the body. Current research using ES cells is mainly focused on the efficient generation of specific cell types by employing optimal differentiation conditions, which often requires the genetic manipulation of ES cells. As a way of developing an efficient system to regulate foreign gene expression in ES cells, we have inserted the gene encoding Corynebacterium diphtheria toxin-A (DTA) into an autonomously induced plasmid under positive doxycycline control ('Tet-on' system). In this study, we demonstrate that this system can lead to the cell death of mouse ES cells by the induction of DTA expression when exposed to the tetracycline derivative, doxycycline. MTT assay showed that this induction resulted in the apoptosis of ES cells.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.1
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• pp.59-68
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• 2016

For comparison of tetracycline-resistant ($Tc^R$) genes, we obtained 21 and 14 $Tc^R$ Staphylococcus spp. from marine environment and human patient, respectively. Although all isolates from human were identified as Staphylococcus aureus, higher proportion of $Tc^R$ isolates (12 out of 14) from human were utilizing tet(M) gene compared to that of $Tc^R$ isolates (6 out of 21) from marine environment. Additionally, collaborated utilization of tet(M) and erm(A) in $Tc^R-Em^R$ S. aureus in human patient, but not in $Tc^R$ Staphylococcus spp. isolates from marine environment was also characterized. Based on the nucleotide sequence of transposon related to $Tc^R$ gene, we confirmed the origin of tet(M) gene in $Tc^R$ Staphylococci isolated from marine environments and human are derived from Tn916/1545-like and Tn5801 transposon, respectively. It is the first report showing the presence of Tn5801 in all $Tc^R$ S. aureus carrying tet(M) in human patient. Alignment of the fully sequenced tet(M) from marine environmental isolates was also agreed with the determined transposons by showing the genomic mosaic structure composed with three genomic parts from Tn916/1545 and unknown transposons. Genetic characteristics of these tet(M) in environmental isolates were similar to each other but different from those in isolates from human showing only tet(M) from Tn916/5801 type. It may imply the presence of less dramatic communication of antibiotic resistant genes between Staphylococci isolated from marine environment and human.

• Annals of Rehabilitation Medicine
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• v.42 no.6
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• pp.846-853
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• 2018

Objective To compare the effects of low intensity ultrasound (LIUS), traditional exercise therapy (TET), low level laser therapy (LLLT) and TET on temporomandibular joint (TMJ) pain and trismus following recovery from head and neck cancer (HNC). Methods Sixty participants following, who had experienced HNC, were randomly allocated to three groups of 20 people each. Each group received different therapy. Group A received LIUS and TET; group B received LLLT and TET; while group C received TET. All 60 participants were evaluated under the visual analog scale (VAS), the University of Washington Quality of Life questionnaire (UW-QOL) and the Vernier caliper scale (VCS) at the beginning of the therapies and after 4 weeks. Results ANOVA test revealed significant improvements across all three groups with outcomes of p<0.05. The results of the UW-QOL questionnaire showed a significant difference between groups A, B and C in favor of group A (p<0.05). The VAS results showed a more improvement in group A as compared to group B (p<0.05), while there was no statistical difference between groups B and C (p>0.05). The VCS results showed more improvement for the individuals in group B as compared to those in group C (p<0.05), while there was minimal difference between groups A and B (p>0.05). Conclusion The LIUS and TET are more effective than LLLT and/or TET in reducing TMJ pain and trismus following HNC.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.177-177
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• 1998

In the previous report, tetrandrine (TET) and fangchinoline (FAN) showed antithrombotic and antiplatelet aggregation activities. The present study was undertaken to investigate the effects of tetrandrine and fangchinoline on human platelet aggregation, formation of thromboxane B$_2$ and coagulation of platelet poor plasma. TET and FAN inhibited platelet activating factor (PAF) induced human platelet aggregation, but didn't inhibit the specific binding of PAF to its receptor. Meanwhile, TET and FAN also inhibited PAF, thrombin and arachidonic acid induced thromboxane B$_2$ formation in human washed platelets. In addition, neither TET nor FAN showed any anticoagulation activities in the measurement of the activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time (TT) using human platelet poor plasma. These results suggest that antithrombotic effects of TET and FAN in mice may be mainly related to the antiplatelet aggregation activities, and the antiplatelet aggregation effects may be related to the intracellular messenger system such as TXA$_2$ formation etc., but not to the binding of PAF to PAF-receptor on the platelet membrane directly.

• Fisheries and Aquatic Sciences
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• v.12 no.1
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• pp.24-28
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• 2009

A tetracycline resistant Vibrio parahaemolyticus, capable of growing on TCBS medium containing tetracycline, was isolated from cultivated fishes. A gene responsible for the tetracycline resistance was cloned from chromosomal DNA of the V. parahaemolyticus strain using Escherichia coli KAM3, which lacks major multi-drug efflux pumps (${\Delta}acrB$) as host cells. The nucleotide sequence and homology analysis revealed an open reading frame (ORF) for tetracycline resistance protein (TetB). In order to characterize the antibiotic resistance of TetB originated from the V. parahaemolyticus strain, the gene was sub cloned into plasmid pSTV28. The resulting plasmid was designated as pSTVTetB and transformated into E. coli KAM3. E. coli KAM3 cells harboring the recombinant plasmid pSTVTetB are able to grow on plates containing tetracycline and oxytetracycline but not doxycycline, indicating that the tetB gene confers the tetracycline- and oxytetracycline-resistance to the host cell.

• Reproductive and Developmental Biology
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• v.31 no.3
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• pp.153-159
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• 2007

In this study, using FIV-based lentivirus vector system, we tried to express hG-CSF in tetracycline-controllable manner. hG-CSF influences the proliferation, differentiation, and survival of cells in the neutrophil lineage. To enhance stability and translation of hG-CSF transcript, WPRE sequence was also introduced into FIV-Tet-On vector at downstream region of either the hG-CSF gene or the sequence encoding rtTA. Primary culture cells (CEF, chicken embryonic fibroblast; PFF, procine fetal fibroblast) infected with the recombinant FIV were cultured in the medium supplemented with or without doxycycline for 48 hours, and induction efficiency was measured by comparing the hG-CSF gene expression level using quantitative real-time PCR, Western blot and ELISA. Higher hG-CSF expression and tighter expression control were observed from the vector in which the WPRE sequence was placed at downstream of the hG-CSF (in CEF) or rtTA (in PEE) gene. This FIV-Tet-On vector system may be helpful in solving serious physiological disturbance problems which has continuously hampered successful production of transgenic animals and gene therapy.

• Progress in Medical Physics
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• v.33 no.4
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• pp.172-179
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• 2022

Recently, tetrahedral phantoms have been newly adopted as international standard mesh-type reference computational phantoms (MRCPs) by the International Commission on Radiological Protection, and a program has been developed to convert them to computational tomography images and DICOM-RT structure files for application of radiotherapy. Through this program, the use of the tetrahedral standard phantom has become available in clinical practice, but utilization has been difficult due to various library dependencies requiring a lot of time and effort for installation. To overcome this limitation, in this study a newly developed TET2DICOM-GUI, a TET2DICOM program based on a graphical user interface (GUI), was programmed using only the MATLAB language so that it can be used without additional library installation and configuration. The program runs in the same order as TET2DICOM and has been optimized to run on a personal computer in a GUI environment. A tetrahedron-based male international standard human phantom, MRCP-AM, was used to evaluate TET2DICOM-GUI. Conversion into a DICOM-RT dataset applicable in clinical practice in about one hour with a personal computer as a basis was confirmed. Also, the generated DICOM-RT dataset was confirmed to be effectively implemented in the radiotherapy planning system. The program developed in this study is expected to replace actual patient data in future studies.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1613-1616
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• 2008

A Transcutaneous Energy Transmission System (TET) has been developed for the wireless energy transmission with two magnetically coupled coils. A resonance circuit is used to raise the induced voltage and current of the secondary coil. Its resonance frequency depends on the internal resistance of circuit and the transferred energy. Because the transferred energy usually changes in wide range, the output voltage is unstable and the energy transferring efficiency decrease. A push-pull class E amplifier is usedto generate high frequency AC voltage. To maintain proper resonance frequency, the voltage output of the amplifier was continuously monitored and adjusted to the optimized resonance frequency. Because of its high frequency (370 kHz), a phase lockedloop circuit and a comparator are used to monitor the output waveform. The results of experimentaldata show that the PLL circuit can increase the transmission efficiency and stabilize the output voltage of TET.

• Journal of Pharmacopuncture
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• v.18 no.4
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• pp.20-25
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• 2015

Objectives: Recently, thread-embedding therapy (TET) has been widely applied in Korean medicine for cosmetic purposes such as reducing skin wrinkles. An inserted thread was reported to have induced continuous stimulation, followed by support for connective tissue regeneration. However, the potential role of TET in hair-growth has not yet been reported. Methods: We designed this study to evaluate whether TET has a hair-growth-promoting effect. C57 black 6 (C57BL/6) mice were divided into three groups: normal saline-treated, minoxidil-treated, and thread-embedded groups. Normal saline or 5% minoxidil was topically sprayed on the dorsal skin of the mice once a day for 16 days. Medical threads were embedded into the dorsal skin of the mice in a single application. Hair growth activity was evaluated by using dermoscopic and microscopic observations. Sections of the dorsal skin were stained with hematoxylin and eosin. Expressions of bromodeoxyuridine (BrdU), proliferating cell nuclear antigen (PCNA), fibroblast growth factor-7 (FGF-7), and fibroblast growth factor-5 (FGF-5) were detected by using immunohistochemical staining. A reverse transcription-polymerase chain reaction (RT-PCR) analysis was adopted to measure the messenger RNA (mRNA) expressions of FGF-7 and FGF-5. Results: TET enhanced anagen development in the hair follicles of C57BL/6 mice. The expressions of BrdU and PCNA, both of which imply active cellular proliferation, were increased by using TET. Moreover, TET increased the expression of FGF-7, an anagen-inducing growth factor, while decreasing the expression of FGF-5, an anagen-cessation growth factor, both at the protein and the mRNA levels. Conclusion: TET enhanced hair re-growth in C57BL/6 mice. TET regulated the expressions of anagen-associated growth factors and activated the proliferation of hair follicular cells in depilated skin lesions. Considering its long-lasting effect, TET may be a good alternative therapeutic for the treatment of alopecia.

• Journal of Embryo Transfer
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• v.23 no.2
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• pp.81-86
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• 2008

This study compared the pregnancy rates of Korean native donor cattle after either a timed artificial insemination (TAI) or embryo transfer (TET) following the synchronization of ovulation using a controlled internal drug release (CIDR) device together with estradiol benzoate (EB) and prostaglandin $F_{2{\alpha}}$ ($PGF_{2{\alpha}}$). Fifty five cows and 8 heifers which had been previously used for embryo production were assigned to two treatments: (1) Thirty-two cattle received a CIDR device and 2 mg EB (Day 0), 25 mg $PGF_{2{\alpha}}$ injection at the time of CIDR removal on Day 7, and 1 mg EB injection on Day 8. All of the cattle received a TAI 30 h (Day 9) after the second EB injection (TAI group). (2) Thirty-one cattle received the same hormonal treatments as in the TAI group. The cattle with corpus luteum (CL) received a TET on Day 16 using frozen-thawed embryos (TET group). Ultrasonographic observations demonstrated that the proportion of cattle with synchronized ovulation on Day 10 and the concomitant formation of new CL on Day 13 did not differ between groups (p>0.05); the overall mean rates were 65.1 and 73.0%, respectively. The conception and pregnancy rates did not differ (p>0.05) between the TAI (12.5% and 12.5%) and TET groups (13.0% and 9.7%), respectively. We conclude that the pregnancy rate following TAI or TET in Korean native donor cattle was poor, which might be due in part to a poor synchrony of ovulation and concomitant CL formation.