• Journal of Yeungnam Medical Science
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• v.35 no.2
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• pp.156-164
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• 2018

Environmental contaminants are one of the important causal factors for development of various human diseases. In particular, the perinatal period is highly vulnerable to environmental toxicants and resultant dysregulation of fetal development can cause detrimental health outcomes potentially affecting life-long health. Perfluoroalkyl compounds (PFCs), emerging environmental pollutants, are man-made organic molecules, which are widely used in diverse industries and consumer products. PFCs are non-degradable and bioaccumulate in the environment. Importantly, PFCs can be found in cord blood and breast milk as well as in the general population. Due to their physicochemical properties and potential toxicity, many studies have evaluated the health effects of PFCs. This review summarizes the epidemiological and experimental studies addressing the association of PFCs with neurotoxicity and immunotoxicity. While the relationships between PFC levels and changes in neural and immune health are not yet conclusive, accumulative studies provide evidence for positive associations between PFC levels and the incidence of attention deficit hyperactivity disorder and reduced immune response to vaccination both in children and adults. In conclusion, PFCs have the potential to affect human health linked with neurological disorders and immunosuppressive responses. However, our understanding of the molecular mechanism of the effects of PFCs on human health is still in its infancy. Therefore, along with efforts to develop methods to reduce exposure to PFCs, studies on the mode of action of these chemicals are required in the near future.

• Journal of Yeungnam Medical Science
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• v.35 no.2
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• pp.213-218
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• 2018

Background: Body fats, especially both of abdominal fat pad mass and skeletal muscle fat content, are inversely related to insulin action. Therefore, methods for decreasing visceral fat mass and muscle triglyceride content may be helpful for the prevention of insulin resistance. Methods: Thalidomide, used for its anti-angiogenic and anti-inflammatory properties, was administered to rats for 4 weeks. A 10% solution of thalidomide in dimethyl sulfoxide was injected daily into the peritoneal cavity as much as 100 mg/kg of body weight. Results: The total visceral fat pad mass in the thalidomide-treated group was 11% lower than in the control group. The size of adipocytes of the epididymal fat pad mass in the thalidomide-treated group was smaller than in the control group. The intraperitoneal thalidomide treatment increased triglyceride concentrations by 16% in the red muscle, but not in the white muscle. Conclusion: The results suggested that intraperitoneal thalidomide treatment inhibited abdominal fat accumulation, and that the free fatty acids in the blood were preferentially accumulated in the red muscle rather than in the white muscle.

• Medical Lasers
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• v.10 no.3
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• pp.123-131
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• 2021

Optical imaging modalities with properties of real-time, non-invasive, in vivo, and high resolution for image-guided surgery have been widely studied. In this review, we introduce two optical imaging systems, that could be the core of image-guided surgery and introduce the system configuration, implementation, and operation methods. First, we introduce the optical coherence tomography (OCT) system implemented by our research group. This system is implemented based on a swept-source, and the system has an axial resolution of 11 ㎛ and a lateral resolution of 22 ㎛. Second, we introduce a fluorescence imaging system. The fluorescence imaging system was implemented based on the absorption and fluorescence wavelength of indocyanine green (ICG), with a light-emitting diode (LED) light source. To confirm the performance of the two imaging systems, human malignant melanoma cells were injected into BALB/c nude mice to create a xenograft model and using this, OCT images of cancer and pathological slide images were compared. In addition, in a mouse model, an intravenous injection of indocyanine green was used with a fluorescence imaging system to detect real-time images moving along blood vessels and to detect sentinel lymph nodes, which could be very important for cancer staging. Finally, polarization-sensitive OCT to find the boundaries of cancer in real-time and real-time image-guided surgery using a developed contrast agent and fluorescence imaging system were introduced.

• International Journal of Industrial Entomology and Biomaterials
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• v.45 no.2
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• pp.70-77
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• 2022

Wet-spun regenerated silk fibroin (RSF) fibers have been extensively studied owing to their 1) useful properties as biomaterials, including good blood compatibility and cyto-compatibility; 2) the various methods available to control the structural characteristics and morphology of the fiber, and 3) the possibility of fabricating blended fibers and new material-embedded fibers. In this study, silk nanofibrils prepared using a new method were embedded in RSF to fabricate wet-spun silk nanofibril/RSF composite fibers. Up to 2% addition of silk nanofibril, the silk nanofibril/RSF dope solution showed slight shear thinning, and the G' and G" of the dope solution were similar. However, above 3% silk nanofibril content, the viscosity of the dope solution significantly increased. In addition, shear thinning was remarkably evident, and the G' of the dope solution was much higher than the G", indicating a very elastic state. As the silk nanofibril content was increased, the wet-spun silk nanofibril/RSF composite fiber became uneven, with a rough surface, and more beaded fibers were produced. Scanning electron microscopy observations revealed that the beaded fibers were attributed to the inhomogeneous dispersion and presence of agglomerates of the silk nanofibrils. As the silk nanofibril content and RSF concentration increased, the maximum draw ratio decreased, indicating the deterioration of the wet spinnability and post-drawing performance of silk nanofibril/RSF.

• International Journal of Industrial Entomology and Biomaterials
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• v.44 no.2
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• pp.37-43
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• 2022

Silkworm food has been found to be effective for dementia, liver function, lowering blood sugar, and possesses antioxidant properties, which has been attracting attention as a health functional food. In this study, methods for enhancing the functionality of silkworms were explored and the production potential of high-functional silkworms was analyzed. For enhancing antioxidant activity, ascorbic acid, caffeic acid, laminarin, and glutathione were injected or fed to 5th instar silkworms, and the antioxidant activity of silkworm extract was comparatively analyzed. There was no significant change in polyphenol and flavonoid content, but it was confirmed that 2,2-diphenyl-1-picrylhydrazyl radical scavenging ability, superoxide dismutase-like activity, and reducing power were slightly increased after injection of ascorbic acid, caffeic acid, and glutathione. To confirm the increase in antioxidant efficacy through feeding, an inducer was mixed with sucrose and sprayed on mulberry leaves. As a result, the growth rate of silkworms improved and all indicators of antioxidant activity were improved in silkworms fed with ascorbic acid and glutathione. Considering these results, producing high-functional silkworms was deemed possible.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.6
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• pp.894-902
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• 2022

This study investigated the effects of photoperiod (NL 12L:12D and LL 24L:0D) and body sizes (30 g and 50 g) on parr-smolt transformation, post-smolt growth and blood properties in the off-season parr-smolt stage of Atlantic salmon reared in a recirculating aquaculture system (RAS). Potential off-season salmon smolt were reared in a freshwater RAS for 80 days and then all experimental fish were transferred to seawater. In both LL groups (LL-30 and LL-50), we recorded and increase in specific growth rate and reduction in feed conversion, although there were no significant difference in body size. The values of osmolality, and serum Na⁺, Cl^- and cortisol concentrations in the LL groups were maintained at lower levels than in NL group fish, and LL group fish were observed to recover to the pre-seawater adaptation state more rapidly than those in the NL group. ID chips were inserted in all smolts reared in freshwater. These fish were subsequently transferred to full-strength seawater and thereafter individual growth rates were monitored for 120 days. The results indicated that compared with smolt reared under natural photoperiodic condition, 24 h lighting in freshwater contributed to enhancing post-smolt specific growth rate in seawater.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.2
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• pp.79-86
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• 2022

Numerous fabrication techniques have been used to mimic cylindrical natural tissues, such as blood vessels, tendons, ligaments, and skeletal muscles. However, most processes have limitations in achieving the biomimetic properties of multilayered and porous architectures. In this study, to embrace both features, a novel self-assembly method was proposed using electrospun microfibrous sheets. A bilayer microfibrous structure, comprising two sheets with different internal stresses, was fabricated by electrospinning a polycaprolactone (PCL) sheet on a uniaxially stretched thermoplastic polyurethane (TPU) sheet. Then, by removing the stretching tension, the sheet was rolled into a hollow cylindrical structure with a specific internal diameter. The internal diameter could be quantitatively controlled by adjusting the thickness of the PCL sheet against that of the TPU sheet. Through this self-assembly method, biomimetic cylindrical structures with multilayer and porous features can be manufactured in a stable and controllable manner. Therefore, the resulting structures may be applied to various tissue engineering scaffolds, especially vascular and connective tissues.

• Journal of Korean Medical classics
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• v.35 no.3
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• pp.91-106
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• 2022

Objectives : To examine the developmental process of the Pi-Yin theory since the Huangdineijing to Miu Xiyong. Methods : Related contents since the Huangdineijing to Miu Xiyong was searched to examine the development of the Pi-Yin theory. Results & Conclusions : In the Huangdineijing and Shanghanzabinglun, the origin of the Pi's body fluids that nurtures everywhere is explained to be the Wei, which limited the development of the Pi-Yin theory. Liu Wansu understood tonification of the Pi by means of moistening medicinals to mean adding Pi-Yin based on the manifestation of dryness in the case of dampness deficiency which is the main Qi of the Pi and Wei. Zhu Danxi understood adding Pi-Yin as accomplished by supplementing Blood. The understanding of the nature of Pi to be 'likes dryness and hates dampness' leading to thinking that drying dampness tonifies the Pi was the reason why the Pi-Yin theory could not develop fully. Miu Xiyong accepted theories of both Li Dongyuan and Zhu Danxi, and constructed the Pi-Yin theory to bring caution to the unwanted effects of using Baizhu wrongly. Through examination of the developmental process of the Pi-Yin theory, it could be understood that rather than focusing on the physiological function of the Pi-Yin and ways of maintaining its proper functioning, the theory was developed to bring caution to using medicinals with dry and hot properties that could dry the Pi-Yin.

• BMB Reports
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• v.56 no.4
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• pp.246-251
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• 2023

Obesity increases the risk of mortality and morbidity because it results in hypertension, heart disease, and type 2 diabetes. Therefore, there is an urgent need for pharmacotherapeutic drugs to treat obesity. We performed a screening assay using natural products with anti-adipogenic properties in 3T3-L1 cells and determined that tschimganidine, a terpenoid from the Umbelliferae family, inhibited adipogenesis. To evaluate the anti-obesity effects of tschimganidine in vivo. Mice were fed either a normal chow diet (NFD) or a high-fat chow diet (HFD) with or without tschimganidine for 12 weeks. Treatment with tschimganidine decreased lipid accumulation and adipogenesis, accompanied by reduced expression of adipogenesis and lipid accumulation-related factors. Tschimganidine significantly increased the phosphorylation of AMP-activated protein kinase (AMPK) and decreased that of AKT. Depletion of AMPK relieved the reduction in lipid accumulation resulting from tschimganidine treatment. Moreover, tschimganidine administration drastically reduced the weight and size of both gonadal white adipose tissue (WAT) and blood glucose levels in high-fat diet-induced obese mice. We suggest that tschimganidine is a potent anti-obesity agent, which impedes adipogenesis and improves glucose homeostasis. Tschimganidine can then be evaluated for clinical application as a therapeutic agent.

• Nutrition Research and Practice
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• v.17 no.4
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• pp.698-716
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• 2023

BACKGROUND/OBJECTIVES: The aim of this study was to evaluate the sensory properties of antioxidant-rich bread made by adding pomegranate peels and their effects on anthropometric measurements and metabolic and oxidative parameters of individuals with type 2 diabetes after consumption. SUBJECTS/METHODS: This randomized, double-blind, placebo-controlled study was conducted with 22 individuals aged between 19 and 64 years who had been diagnosed with type 2 diabetes for at least 5 years, used only metformin, did not lose more than 10% of their body weight in the last 6 months, and had a body mass index of ≥ 25.0 kg/m². While the study group (n = 11) consumed bread containing 500 mg pomegranate peel daily for 8 wk, the control group (n = 11) consumed standard bread. Anthropometric measurements and metabolic and oxidative parameters of individuals were evaluated at the beginning and end of the study. RESULTS: Decreases were detected in the waist circumference, waist/hip and waist/height ratios, body fat percentages, blood pressure, and serum insulin, triglyceride, and total cholesterol levels in the individuals in the treatment group, compared with those in the control group (P < 0.05). CONCLUSIONS: Pomegranate peel consumption by individuals with type 2 diabetes may have positive effects on anthropometric measurements and glycemic and lipid parameters.