• Fisheries and Aquatic Sciences
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• v.18 no.2
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• pp.131-135
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• 2015

Two new bitter-tasting cyclic peptides comprising six amino acids, namely gamakamide C and D, were isolated from cultured oysters Crassostrea gigas. Dimethylaminoazobenzene sulfonyl-amino acid analysis detected Val and Leu in gamakamide C and Ile and Leu in gamakamide D. The molecular formula of gamakamide C was determined as $C_{43}H_{60}N_{7}O_8S$ by high-resolution fast atom bombardment mass spectroscopy (HR FAB-MS) ($[M+H]^+m/z822.4200{\Delta}-2.4mmu$), and that of gamakamide D was determined as $C_{43}H_{62}N_7O_8S$ by HR FAB-MS ($[M+H]^+m/z836.4379{\Delta}-2.0mmu$). Comparison of amino acid analyses and fragment ions by MS/MS among gamakamide C, D, and E (known), the structures of gamakamide C and D were confirmed $as-{\small{L}}-Val-{\small{L}}-Met(SO)-{\small{L}}-NMe-Phe-{\small{L}}-Leu-{\small{D}}-Lys-{\small{L}}-Phe-$ and $-{\small{L}}-Ile-{\small{L}}-Met(SO)-{\small{L}}-NMe-Phe-{\small{L}}-Leu-{\small{D}}-Lys-{\small{L}}-Phe-$, respectively.

• Journal of Sensor Science and Technology
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• v.26 no.4
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• pp.245-250
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• 2017

A novel method to implement a birdcage-type receiving coil sensor for use in a magnetic resonance imaging(MRI) system has been demonstrated employing a flexible printed circuit board (FPCB) fabrication technique. Unlike the conventional methods, the two-dimensional shape of the coil sensor is first implemented as a FPCB and then it is attached to the surface of a cylindrical supporting structure to implement the three-dimensional birdcage-type coil sensor. The proposed method is very effective to implement object-specific MRI coil sensors especially for small animal measurements in research and preclinical applications since the existing well-developed FPCB-based techniques can easily meet the requirements on accuracies and costs during coil implement process. The performances of the coil sensor verified through $^1H$ 1.5T MRI measurements for small animals and it showed excellent characteristics by providing a high spatial precision and a high signal-to-noise ratio.

• Journal of Veterinary Clinics
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• v.25 no.1
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• pp.19-22
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• 2008

Adenomyosis is a nonneoplastic proliforation of uterine glands characterized by multicentric infiltration of endometrial tissues into the myometrium. A female domestic short hair cat with unknown age was referred to local animal hospital in Busan for ovariohysterectomy to prevent the unwanted offspring. At the time of surgery, the uterus was enlarged with multiple nodular protrusion on the serosa. On the cut surface of uterus, elevation of the endometrium and hypertrophied myometrium were observed. Microscopically, the uterus was characterized by severe proliforation of endometrial glands into the lumen and within the myometrium. The intra-myometrial endometrium is circumferentially surrounded by bundles of hypertrophic smooth muscle cells. These endometrial glands had tall columnar epithelium lacking nuclear atypia and mitoses. In our best knowledge, this is the first report of feline adenomyosis in Korea.

• Toxicological Research
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• v.35 no.1
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• pp.65-74
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• 2019

Tetrahydrocurcumin (THC) is a major metabolite of curcumin, which is obtained from Curcuma longa. THC has various benefits and overcomes the bioavailability issue of curcumin. To establish it as a pharmacologically active molecule, its safety profile has to be determined. Thus, the present study aimed to determine the preclinical safety profile of THC in a 90-day subchronic and reproductive/developmental toxicity study in Wistar rats. THC at oral doses of 100, 200, and 400 mg/kg was administered daily for 90 days. Rats in the recovery group were kept for 14 days after treatment termination. The animals were observed for treatment-related morbidity, mortality, and changes in clinical signs, clinical pathology, and histopathology. In the reproductive/developmental toxicity study, THC at 100, 200, and 400 mg/kg was administered orally to rats and the reproductive/developmental parameters in adult male and female rats and pups were observed. THC at up to 400 mg/kg/day of did not have any significant effect on all parameters in male and female rats in both toxicity studies. Thus, 400 mg/kg/day can be considered as the no-observed-adverse-effect-level of THC in rats.

• Oral Biology Research
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• v.42 no.4
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• pp.235-240
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• 2018

Standard oral and maxillofacial three-dimensional model was developed with patients' medical data while virtual reality (VR) simulator was developed in conjunction with head mount display (HMD) and Haptic device. The objective of this study was to evaluate the preclinical use of a VR training simulator in tooth preparation practice. Eighty-nine dental students were trained how to operate the simulator. The participants were then given sufficient time on the simulator to practice dental preparation. The students experience and opinion was then taken in through filling of questionnaires. On average content received 1.8 points, anatomy had 2.5 points, 2.6 points for the applicability, and 2.0 for the usability. As for the detailed items scores, queries about the possible development of the simulator and the interest of the learning process through the simulator were the highest at 3.1 and 3.0 points, respectively. Question about the benefit of the HMD and the haptic device during the practice had 1.5 and 1.6 points, respectively. The average total score was 2.2 points. VR tooth preparation simulator in the field of clinical dental education has powerful potential in regard to realistic models, environments, vision, posture, and economical efficiency.

• Medical Lasers
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• v.10 no.2
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• pp.82-89
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• 2021

Background and Objectives Due to changes in diet and lifestyle, the number of obese people worldwide is steadily increasing. Obesity has an adverse effect on a healthy life, so it needs treatment and improvement. Research related to this is continuously being conducted. Materials and Methods The laser system to compact designed using 808 nm laser diode and Neodymium Yttrium orthovanadate generates a 1064 nm wavelength, the periodically polarized nonlinear crystal pumping laser beam. The pulsed 1064 nm wavelength beam passing through the AO Q-switch is used as the pumping light of the nonlinear optical crystal and is irradiated to the periodic polarized nonlinear optical crystal with a quasi-phase matching period. Nonlinear optical crystals use an oven to control the temperature to generate the desired 1980 nm and 2300 nm wavelengths. Results The 1980 nm and 2300 nm wavelengths generated by temperature control of nonlinear optical crystals are effective for lipolysis. A fiber catheter was used so that the laser could be directly irradiated to the fat cells. In particular, the new wavelength (1980 nm, 2300 nm) can increase the fat reduction effect with low energy (1.3 W). When a laser with a combination wavelength of 1980 nm and 2300 nm was used, an average lipolysis effect of 20% was obtained. Conclusion A mid-infrared lipolysis laser system with excellent absorption of fat and water has been developed. We conducted a princlinical study to confirm the efficacy and safety of the lipolysis laser system, and obtained good results for lipolysis with low energy.

• Journal of Ginseng Research
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• v.46 no.2
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• pp.206-213
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• 2022

Ginsenoside Rb2 is an active protopanaxadiol-type saponin, widely existing in the stem and leave of ginseng. Rb2 has recently been the focus of studies for pharmaceutical properties. This paper provides an overview of the preclinical and clinical pharmacokinetics for Rb2, which exhibit poor absorption, rapid tissue distribution and slow excretion through urine. Pharmacological studies indicate a beneficial role of Rb2 in the prevention and treatment of diabetes, obesity, tumor, photoaging, virus infection and cardiovascular problems. The underlying mechanism is involved in an inhibition of oxidative stress, ROS generation, inflammation and apoptosis via regulation of various cellular signaling pathways and molecules, including AKT/SHP, MAPK, EGFR/SOX2, TGF-β1/Smad, SIRT1, GPR120/AMPK/HO-1 and NF-κB. This work would provide a new insight into the understanding and application of Rb2. However, its therapeutic effects have not been clinically evaluated. Further studies should be aimed at the clinical treatment of Rb2.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.8 no.2
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• pp.113-118
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• 2022

Gadolinium neutron capture therapy (Gd-NCT) is a precision radiation therapy that kills cancer cells using the neutron capture reaction that occurs when ¹⁵⁷Gd hits thermal neutrons. ¹⁵⁷Gd has the highest thermal neutron capture cross section of 254,000 barns among stable isotopes in the periodic table. Another stable isotope, ¹⁵⁵Gd, also has a high thermal neutron trapping area (~ 60,700 barns), so gadolinium that exists in nature can be used as a Gd-NCT drug. Gd-NCT is a mixed kinetic energy of low-energy and high-energy ionizing particles, which can be uniformly distributed throughout the tumor tissue, thereby solving the disadvantage of heterogeneous dose distribution in tumor tissue. The Gd complexes of small-sized molecule are widely used as contrast agents for magnetic resonance imaging (MRI) in clinical practice. Therefore, these compounds can be used not only for diagnosis but also therapy when considering the concept of Gd-NCT. This multifunctional trial can look forward to new medical advance into NCT clinical practices. In this review, we introduce gadolinium compounds suitable for Gd-NCT and describe the necessity of image guided Gd-NCT.

• Biomedical Science Letters
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• v.29 no.2
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• pp.53-57
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• 2023

The main objective of pathologists is to achieve accurate lesion diagnoses, which has become increasingly challenging due to the growing number of pathological slides that need to be examined. However, using digital technology has made it easier to complete this task compared to older methods. Digital pathology is a specialized field that manages data from digitized specimen slides, utilizing image processing technology to automate and improve analysis. It aims to enhance the precision, reproducibility, and standardization of pathology-based researches, preclinical, and clinical trials through the sophisticated techniques it employs. The advent of whole slide imaging (WSI) technology is revolutionizing the pathology field by replacing glass slides as the primary method of pathology evaluation. Image processing technology that utilizes WSI is being implemented to automate and enhance analysis. Artificial intelligence (AI) algorithms are being developed to assist pathologic diagnosis and detection and segmentation of specific objects. Application of AI-based digital pathology in biomedical researches is classified into four areas: diagnosis and rapid peer review, quantification, prognosis prediction, and education. AI-based digital pathology can result in a higher accuracy rate for lesion diagnosis than using either a pathologist or AI alone. Combining AI with pathologists can enhance and standardize pathology-based investigations, reducing the time and cost required for pathologists to screen tissue slides for abnormalities. And AI-based digital pathology can identify and quantify structures in tissues. Lastly, it can help predict and monitor disease progression and response to therapy, contributing to personalized medicine.

• Journal of Digestive Cancer Research
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• v.6 no.2
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• pp.64-68
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• 2018

Pancreatic ductal adenocarcinoma is a dismal prognosis and 5^th leading cause of cancer related death in Korea. A large proportion of patients are diagnosed at advanced or metastatic stage. Therefore systemic chemotherapy has become the mainstay of treatment for pancreatic cancer. For most patients advanced or metastatic pancreatic cancer that has a good Eastern Cooperative Oncology Group performance status (ECOG PS) 0 or 1, we can recommend for FOLFIRINOX (leucovorin, 5-fluorouracil [5-FU], irinotecan and oxaliplatin) and gemcitabine plus nanoparticle albumin-bound paclitaxel (nab-paclitaxel). Currently, steps towards improved therapeutic efficacy of palliative chemotherapy have been made by introducing these regimens. For patients with an ECOG PS of 2, gemcitabine monotherapy or S1 alone is recommended. The second-line therapy for patients initially treated with gemcitabine-based chemotherapy includes provide FOLFOX (leucovorin, 5-FU, and oxaliplatin), capecitabine plus oxaliplatin, and 5-FU plus liposomal irinotecan. The gemcitabine-based chemotherapy is a reasonable choice for patients treated with FOLFIRINOX. Currently, studies on selecting patients for biomarkers related to molecular biologic features of tumors are underway for the realization of precise medicine, and the development and verification of preclinical models for the development of new therapeutic agents are being carried out continuously.