• Korean journal of applied entomology
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• v.34 no.1
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• pp.20-32
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• 1995

Adult diapause in insects is characterized by suppression of reproductive development. It is induced by environmental cues such as photoperiod, temperature, food availability, and other conditions Diapause-inducing environment is recognized and analyzed by the brain of the insects. The interpreted information is conveyed via endocrine system to target tissues such as ovaries, fat body, and other tissues. From this signal hierarchy of a brain-endocrine-target tissue axis, several factors are involved to express a diapause trait in a quantitative mode, even though the insects show a binomial phenotye between being in diapause or not. Recent works estimated that the number of the factors is relatively small by a series of crossing trials between high and low diapause lines. Heritability of the diapause is quite high (ca. 70%) in some species. Epistasis, sex-linkage, pleiotropism, and other nongenetic components also affect diapause inheritance. Most physiological studies have been focused on control mechanisms of the juvenile hormone (JH) synthesis in corpora allata (CA) because JH level in hemolymph of teneral adults is critical to decide a later developmental mode. Allatostatin, an antagonizer of JH synthesis, has been believed to be a potent brain message to CA for adult diapause induction.

• Journal of Dairy Science and Biotechnology
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• v.34 no.2
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• pp.75-82
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• 2016

Members of the genus Bifidobacterium are prevalent in the human colon and represent up to 90% of all bacteria in fecal samples of breast-fed infants, and 3~5% of adult fecal microbiota. Bifidobacteria produce organic acids, thus reducing the colon pH to a level inhibitory for pathogenic bacteria. They can also detoxify a number of toxic compounds and adhere to the colon mucosa, thus preventing the adherence of pathogens and induction of colon cancer. Recently, we identified a novel Bifidobacterium longum subsp. longum strain, KACC 91563, in a fecal sample of a Korean neonate, and demonstrated its functional properties. We showed that B. longum KACC 91563 alleviates food allergy through mast cell suppression and produces antioxidative and antihypertensive peptides by casein hydrolysis. Dairy products are considered as an ideal food system for the delivery of probiotic cultures to the human gastrointestinal tract. Cheese affords protection to probiotic microbes during gastric transit due to its relatively high pH, more solid consistency, higher fat content, and higher buffering capacity. Incorporation of B. longum KACC 91563 into cheese making is currently under study.

• Natural Product Sciences
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• v.29 no.2
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• pp.91-97
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• 2023

Mangosteen peel extract is a xanthone group, that plays an important role in anti-angiogenesis. This study investigated mangosteen peel extract on cerebral neovascularization in type 2 diabetes mellitus (DM) rats. This study used 36 rats, randomized into six groups: C1 (negative control); C2 (high fat diet (HFD) and mangosteen peel extract at 200 mg/kg BW); C3 (HFD and diabetic); E1, E2, and E3 (HFD, diabetic, and extract at 100, 200, and 400 mg/kg BW respectively). All groups were measured body mass index (BMI), homeostasis model assessment-insulin resistance (HOMA-IR) and β cell function (HOMA-B), and histopathological feature of cerebral vascular (CV). There were significant differences in BMI, HOMA-IR, HOMA-B, and the mean number of CV (all p < 0.05) among treatment groups. E1-3 groups had a significantly lower level of blood glucose and HOMA-IR, and a higher level of HOMA-B and BMI (all p < 0.05) which tends to reduce cerebral neovascularization. HOMA-IR independently had a positive effect to induce neovascularization of CV (p < 0.05, R² = 26.8%). These findings suggested that mangosteen peel extract increased β-cell function sensitivity, and effectively suppressed insulin resistance, BMI, and cerebral neovascularization process in type 2 DM rats.

• Korean Journal of Radiology
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• v.24 no.11
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• pp.1114-1130
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• 2023

Magnetic resonance neurography (MRN) is increasingly used to visualize peripheral nerves in vivo. However, the implementation and interpretation of MRN in the brachial and lumbosacral plexi are challenging because of the anatomical complexity and technical limitations. The purpose of this article was to review the clinical context of MRN, describe advanced magnetic resonance (MR) techniques for plexus imaging, and list the general categories of utility of MRN with pertinent imaging examples. The selection and optimization of MR sequences are centered on the homogeneous suppression of fat and blood vessels while enhancing the visibility of the plexus and its branches. Standard 2D fast spin-echo sequences are essential to assess morphology and signal intensity of nerves. Moreover, nerve-selective 3D isotropic images allow improved visualization of nerves and multiplanar reconstruction along their course. Diffusion-weighted and diffusion-tensor images offer microscopic and functional insights into peripheral nerves. The interpretation of MRN in the brachial and lumbosacral plexi should be based on a thorough understanding of their anatomy and pathophysiology. Anatomical landmarks assist in identifying brachial and lumbosacral plexus components of interest. Thus, understanding the varying patterns of nerve abnormalities facilitates the interpretation of aberrant findings.

• Investigative Magnetic Resonance Imaging
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• v.1 no.1
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• pp.135-141
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• 1997

Purpose: To assess the usefulness of breath-hold fast MR imaging of liver with fat suppression (FS) by application of chemical saturation technique in the diagnosis of regional fatty changes suspected in sonography. Materials and Methods: Thirteen patients who had focal lesions with diffuse, homogeneous signal changes after FS through chemical saturation technique without additional changes of imaging parameter during MR imaging of liver were selected. T1-weighted fast low-angle shot and T2-weighted turbo spin-echo sequences were obtained with or without FS during each single breath-holding session. Subjective changes of signal intensity between the pre-FS and the FS images were compared with the sonographic findings in each lesion. Results: Seven lesions of decreased signal intensity after FS on T1 or T2-weighted images, including three lesions only at FS T1 images, were regarded as focal fat infiltration. All seven lesions had compatible sonographic findings as homogenously echogenic areas. Another six lesions of subjectively increased signal intensity including two lesions only at FS T2 images were regarded as focal fat sparing. All six lesions had sonographic findings as homogenous echo poor areas suggesting focal fat sparing. In cases regarded as fat infiltration, score changes were more prominent at FS T1 images than FS T2 images(p=0.0002). In cases regarded as fat sparing, score changes were more prominent at FS T2 images than FS T1 images(p=0.042). Conclusion: Breath-hold fast T1 and T2-weighted MR imaging with and without chemical saturation pre-pulse may be sufficient for characterization of regional fatty changes in the differential diagnosis of focal hepatic lesion found at sonography.

• Journal of Nutrition and Health
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• v.52 no.6
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• pp.529-539
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• 2019

Purpose: Sprouts of evening primrose (Oenothera laciniata, OL) were reported to have high contents of flavonoids and potent antioxidant activity. This study examined the antioxidant and antiobesity activities of OL sprouts to determine if they could be a natural health-beneficial resource preventing obesity and oxidative stress. Methods: OL sprouts were extracted with 50% ethanol, evaporated, and lyophilized (OLE). The in vitro antioxidant activity of OLE was examined using four different tests. The antiobesity activity and in vivo antioxidant activity from OLE consumption were examined using high fat diet-induced obese (DIO) C57BL/6 mice. Results: The IC₅₀ for the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging and superoxide dismutase (SOD)-like activities of OLE were 26.2 ㎍/mL and 327.6 ㎍/mL, respectively. OLE exhibited the ferric reducing antioxidant power (FRAP) activity of 56.7 ㎍ ascorbic acid eq./mL at 100 ㎍/mL, and an increased glutathione level by 65.1% at 200 ㎍/mL compared to the control in the hUC-MSC stem cells. In an animal study, oral treatment with 50 mg or 100 mg of OLE/kg body weight for 14 weeks reduced the body weight gain, visceral fat content, fat cell size, blood leptin, and triglyceride levels, as well as the atherogenic index compared to the high fat diet control group (HFC) (p < 0.05). The blood malondialdehyde (MDA) level and the catalase and SOD-1 activities in adipose tissue were reduced significantly by the OLE treatment compared to HFC as well (p < 0.05). In epididymal adipose tissue, the OLE treatment reduced the mRNA expression of leptin, PPAR-γ and FAS significantly (p < 0.05) compared to HFC while it increased adiponectin expression (p < 0.05). Conclusion: OLE consumption has potent antioxidant and antiobesity activities via the suppression of oxidative stress and lipogenesis in DIO mice. Therefore, OLE could be a good candidate as a natural resource to develop functional food products that prevent obesity and oxidative stress.

• Investigative Magnetic Resonance Imaging
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• v.18 no.2
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• pp.87-106
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• 2014

Purpose : To describe how a robust implementation of a radial 3D gradient-echo sequence with stack-of-stars sampling can be achieved, to review the imaging properties of radial acquisitions, and to share the experience from more than 5000 clinical patient scans. Materials and Methods: A radial stack-of-stars sequence was implemented and installed on 9 clinical MR systems operating at 1.5 and 3 Tesla. Protocols were designed for various applications in which motion artifacts frequently pose a problem with conventional Cartesian techniques. Radial scans were added to routine examinations without selection of specific patient cohorts. Results: Radial acquisitions show significantly lower sensitivity to motion and allow examinations during free breathing. Elimination of breath-holding reduces failure rates for non-compliant patients and enables imaging at higher resolution. Residual artifacts appear as streaks, which are easy to identify and rarely obscure diagnostic information. The improved robustness comes at the expense of longer scan durations, the requirement for fat suppression, and the nonexistence of a time-to-center value. Care needs to be taken during the configuration of receive coils. Conclusion: Routine clinical use of radial stack-of-stars sequences is feasible with current MR systems and may serve as substitute for conventional fat-suppressed T1-weighted protocols in applications where motion is likely to degrade the image quality.

• Journal of Physiology & Pathology in Korean Medicine
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• v.32 no.1
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• pp.43-50
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• 2018

Korean Red Ginseng (RG) are used as a traditional treatment for improve blood circulation. This experimental study was designed to investigate the inhibitory effects of Korean red ginseng on lipid metabolism in high fat/cholesterol diet (HFCD)-induced hypertriglyceridemia. Sprague Dawley rats were fed the HFCD diet with/without fluvastatin (Flu, positive control) 3 mg/kg/day, and RG 125 or 250 mg/kg/day, respectively. All groups received regular diet or HFCD diet, respectively, for 13 weeks. The last three groups treatment of Flu and RG 125, and RG 250 orally for a period of 9 weeks. Group 1, reular diet; group 2, HFCD diet; group 3, Flu + HFCD diet; group 4, RG 125 + HFCD diet; group 5, RG 250 + HFCD diet. As a result, treatment with low or high doses of RG markedly attenuated plasma levels of triglycerides and augmented plasma levels of high-density lipoprotein (HDL) in HFCD-fed rats. RG and Flu also led to an increase in lipoprotein lipase activity in the HFCD group. On the other hand, RG and Flu led to an decrease in fatty acid synthase and free fatty acid activity in the HFCD group. Treatment with RG suppressed increased expressions of $PPAR-{\alpha}$ and AMPK in HFCD rat liver or muscle. In addition, the RG attenuated triglyceridemia by inhibition of $PPAR-{\gamma}$ and FABP protein expression levels and LXR and SREBP-1 gene expression in liver or muscle. The RG significantly prevented the development of the metabolic disturbances such as hypertriglyceridemia and hyperlipidemia. Taken together, the administration of RG improves hypertriglyceridemia through the alteration in suppression of triglyceride synthesis and accentuated of triglyceride decomposition. These results suggested that RG is useful in the prevention or treatment of hypertriglyceridemia.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.1
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• pp.52-59
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• 2015

Recently the dairy cow industry have faced environmental issues such as eutrophication, global warming, etc. An LCA was used to quantify the environmental impact of a dairy cow system and to identify key issues contributing to the impact. The system boundary crop cultivation for feeding dairy cow, feed production, rearing and manure management (cradle-to-gate). The functional unit was 1 kg of milk (fat protein corrected milk, FPCM) produced. Rearing and cultivation of feed crops stages in system boundary to the environmental impact of the domestic dairy cow system were dominant issues. Techniques such as suppression of enteric fermentation, improvement of the energy efficiency of farm equipment and apparatuses, management of leachate generated during the crop cultivation, and development of controling the loss of fertilizer during crop production would be necessary for the improvement of the environmental key issues of the dairy cow system.

• Korean Journal of Exercise Nutrition
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• v.16 no.2
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• pp.65-71
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• 2012

Oxygen is the final acceptor of electron transport from fat and carbohydrate oxidation, which is the rate-limiting factor for cellular ATP production. Under altitude hypoxia condition, energy reliance on anaerobic glycolysis increases to compensate for the shortfall caused by reduced fatty acid oxidation [1]. Therefore, training at altitude is expected to strongly influence the human metabolic system, and has the potential to be designed as a non-pharmacological or recreational intervention regimen for correcting diabetes or related metabolic problems. However, most people cannot accommodate high altitude exposure above 4500 M due to acute mountain sickness (AMS) and insulin resistance corresponding to a increased levels of the stress hormones cortisol and catecholamine [2]. Thus, less stringent conditions were evaluated to determine whether glucose tolerance and insulin sensitivity could be improved by moderate altitude exposure (below 4000 M). In 2003, we and another group in Austria reported that short-term moderate altitude exposure plus endurance-related physical activity significantly improves glucose tolerance (not fasting glucose) in humans [3,4], which is associated with the improvement in the whole-body insulin sensitivity [5]. With daily hiking at an altitude of approximately 4000 M, glucose tolerance can still be improved but fasting glucose was slightly elevated. Individuals vary widely in their response to altitude challenge. In particular, the improvement in glucose tolerance and insulin sensitivity by prolonged altitude hiking activity is not apparent in those individuals with low baseline DHEA-S concentration [6]. In addition, hematopoietic adaptation against altitude hypoxia can also be impaired in individuals with low DHEA-S. In short-lived mammals like rodents, the DHEA-S level is barely detectable since their adrenal cortex does not appear to produce this steroid [7]. In this model, exercise training recovery under prolonged hypoxia exposure (14-15% oxygen, 8 h per day for 6 weeks) can still improve insulin sensitivity, secondary to an effective suppression of adiposity [8]. Genetically obese rats exhibit hyperinsulinemia (sign of insulin resistance) with up-regulated baseline levels of AMP-activated protein kinase and AS160 phosphorylation in skeletal muscle compared to lean rats. After prolonged hypoxia training, this abnormality can be reversed concomitant with an approximately 50% increase in GLUT4 protein expression. Additionally, prolonged moderate hypoxia training results in decreased diffusion distance of muscle fiber (reduced cross-sectional area) without affecting muscle weight. In humans, moderate hypoxia increases postprandial blood distribution towards skeletal muscle during a training recovery. This physiological response plays a role in the redistribution of fuel storage among important energy storage sites and may explain its potent effect on changing body composition. Conclusion: Prolonged moderate altitude hypoxia (rangingfrom 1700 to 2400 M), but not acute high attitude hypoxia (above 4000 M), can effectively improve insulin sensitivity and glucose tolerance for humans and antagonizes the obese phenotype in animals with a genetic defect. In humans, the magnitude of the improvementvaries widely and correlates with baseline plasma DHEA-S levels. Compared to training at sea-level, training at altitude effectively decreases fat mass in parallel with increased muscle mass. This change may be associated with increased perfusion of insulin and fuel towards skeletal muscle that favors muscle competing postprandial fuel in circulation against adipose tissues.