• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.30.1-30.13
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• 2023

Background: Dysmenorrhea and menstrual cycle changes occur in women working shifts. Circadian rhythm disruption and sleep disturbances associated with shift work leads to health problems. We identified chronotypes and the occurrence of insomnia among newly employed university hospital nurses and investigated the association of these factors with menstrual problems. Methods: We conducted pre-placement health examinations for shift workers using self-reported questionnaires between 2018 and 2020. A total of 463 nurses were included in the study. Sociodemographic data, shift work experience, and information on insomnia were collected from health examination data. In addition, details regarding chronotype, dysmenorrhea, irregular and abnormal menstrual cycles, amenorrhea, and contraceptive use were obtained from the questionnaire. Multiple logistic regression analysis was performed to study the association between chronotype, insomnia, and menstrual problems after controlling for age, body mass index, contraceptive use, amenorrhea, and prior shift work. Results: The prevalence rates of dysmenorrhea, irregular menstrual cycles, and longer menstrual cycles were 23.8%, 14.9%, and 4.1%, respectively. The risk of dysmenorrhea increased in the evening-type (odds ratio [OR]: 3.209; 95% confidence interval [CI]: 1.685-6.113) and those with insomnia (OR: 1.871; 95% CI: 1.074-3.261). Additionally, the risk of an irregular menstrual cycle (OR: 2.698; 95% CI: 1.167-6.237) increased in the evening-type, and the risk of a longer menstrual cycle (OR: 4.008; 95% CI: 1.354-11.864) increased in individuals with insomnia. Conclusions: Our findings suggest that dysmenorrhea is promoted in the evening-type and insomnia individuals. There may be an increased risk of irregular menstrual cycles among evening-type nurses and an increased risk of longer menstrual cycles among those with insomnia. Therefore, factors such as evening-type and insomnia should be considered for the prevention of menstrual problems in women performing shift work.

• Korean Journal of Radiology
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• v.20 no.5
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• pp.749-758
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• 2019

Objective: To investigate whether a computer-aided diagnosis (CAD) system based on a deep learning framework (deep learning-based CAD) improves the diagnostic performance of radiologists in differentiating between malignant and benign masses on breast ultrasound (US). Materials and Methods: B-mode US images were prospectively obtained for 253 breast masses (173 benign, 80 malignant) in 226 consecutive patients. Breast mass US findings were retrospectively analyzed by deep learning-based CAD and four radiologists. In predicting malignancy, the CAD results were dichotomized (possibly benign vs. possibly malignant). The radiologists independently assessed Breast Imaging Reporting and Data System final assessments for two datasets (US images alone or with CAD). For each dataset, the radiologists' final assessments were classified as positive (category 4a or higher) and negative (category 3 or lower). The diagnostic performances of the radiologists for the two datasets (US alone vs. US with CAD) were compared Results: When the CAD results were added to the US images, the radiologists showed significant improvement in specificity (range of all radiologists for US alone vs. US with CAD: 72.8-92.5% vs. 82.1-93.1%; p < 0.001), accuracy (77.9-88.9% vs. 86.2-90.9%; p = 0.038), and positive predictive value (PPV) (60.2-83.3% vs. 70.4-85.2%; p = 0.001). However, there were no significant changes in sensitivity (81.3-88.8% vs. 86.3-95.0%; p = 0.120) and negative predictive value (91.4-93.5% vs. 92.9-97.3%; p = 0.259). Conclusion: Deep learning-based CAD could improve radiologists' diagnostic performance by increasing their specificity, accuracy, and PPV in differentiating between malignant and benign masses on breast US.

• Journal of Microbiology and Biotechnology
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• v.33 no.12
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• pp.1635-1647
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• 2023

Muscle atrophy, which is defined as a decrease in muscle mass and strength, is caused by an imbalance between the anabolism and catabolism of muscle proteins. Thus, modulating the homeostasis between muscle protein synthesis and degradation represents an efficient treatment approach for this condition. In the present study, the protective effects against muscle atrophy of ethanol extracts of Morus alba L. (MA) and Angelica keiskei Koidz. (AK) leaves and their mixtures (MIX) were evaluated in vitro and in vivo. Our results showed that MIX increased 5-aminoimidazole-4-carboxamide ribonucleotide-induced C2C12 myotube thinning, and enhanced soleus and gastrocnemius muscle thickness compared to each extract alone in dexamethasone-induced muscle atrophy Sprague Dawley rats. In addition, although MA and AK substantially improved grip strength and histological changes for dexamethasone-induced muscle atrophy in vivo, the efficacy was superior in the MIX-treated group. Moreover, MIX further increased the expression levels of myogenic factors (MyoD and myogenin) and decreased the expression levels of E3 ubiquitin ligases (atrogin-1 and muscle-specific RING finger protein-1) in vitro and in vivo compared to the MA- and AK-alone treatment groups. Furthermore, MIX increased the levels of phosphorylated phosphoinositide 3-kinase (PI3K), protein kinase B (Akt), and mammalian target of rapamycin (mTOR) that were reduced by dexamethasone, and downregulated the expression of forkhead box O3 (FoxO3a) induced by dexamethasone. These results suggest that MIX has a protective effect against muscle atrophy by enhancing muscle protein anabolism through the activation of the PI3K/Akt/mTOR signaling pathway and attenuating catabolism through the inhibition of FoxO3a.

• Molecules and Cells
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• v.46 no.11
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• pp.688-699
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• 2023

We set up this study to understand the underlying mechanisms of reduced ceramides on immune cells in acute rejection (AR). The concentrations of ceramides and sphingomyelins were measured in the sera from hepatic transplant patients, skin graft mice and hepatocyte transplant mice by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Serum concentrations of C24 ceramide, C24:1 ceramide, C16:0 sphingomyelin, and C18:1 sphingomyelin were lower in liver transplantation (LT) recipients with than without AR. Comparisons with the results of LT patients with infection and cardiac transplant patients with cardiac allograft vasculopathy in humans and in mouse skin graft and hepatocyte transplant models suggested that the reduced C24 and C24:1 ceramides were specifically involved in AR. A ceramide synthase inhibitor, fumonisin B₁ exacerbated allogeneic immune responses in vitro and in vivo, and reduced tolerogenic dendritic cells (tDCs), while increased P3-like plasmacytoid DCs (pDCs) in the draining lymph nodes from allogeneic skin graft mice. The results of mixed lymphocyte reactions with ceranib-2, an inhibitor of ceramidase, and C24 ceramide also support that increasing ceramide concentrations could benefit transplant recipients with AR. The results suggest increasing ceramides as novel therapeutic target for AR, where reduced ceramides were associated with the changes in DC subsets, in particular tDCs.

• The Journal of the Convergence on Culture Technology
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• v.10 no.1
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• pp.345-352
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• 2024

K-Pop Square Media, located at COEX in Samseong-dong, has gained public attention and mass media focus by showcasing various three-dimensional videos on a large LED display. The video content on the distinctive large curved LED display utilizes a form of media façade technique, establishing itself as a new landmark and attraction within the spatial characteristics of the COEX Plaza. This study aims to examine the characteristics of media facades used in outdoor advertising in urban spaces, focusing on K-Pop Square Media. The approach for this research involves three aspects: Firstly, examining the 'spatial characteristics' of urban public spaces by referencing Kevin Lynch's five elements constituting urban space and William J. Mitchell's exploration of smart spaces and changes in spatial paradigms. Secondly, analyzing the 'digital nature' of outdoor advertising through an examination of three types of Digital Out-Of-Home (DOOH) Media. Thirdly, exploring the 'technological advancements and content composition of media facades' by investigating types of display media (projection, LED screens), the inception of media facades, and the latest display technology like Anamorphic displays. Through this research, it becomes evident that K-Pop Square Media exhibits characteristics of publicness, communicativeness, artistry, and placemaking through the spatial characteristics of smart spaces, the media-specific aspects of Digital Out-Of-Home advertising, and the content composition of media facades.

• Journal of Korean Tunnelling and Underground Space Association
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• v.26 no.4
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• pp.327-344
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• 2024

In general tunnel design and analysis, rock masses are often assumed to be isotropic. Under isotropic conditions, material properties are uniform in all directions, leading to a higher evaluation of tunnel stability. However, actual rock masses exhibit anisotropic characteristics due to discontinuities such as joints, bedding planes, and faults, which cause material properties to vary with direction. This anisotropy significantly affects the stress distribution during tunnel excavation, leading to non-uniform deformation and increased risk of damage. Therefore, thorough pre-analysis is essential. This study analyzes the displacement and stress changes occurring during tunnel excavation based on rock anisotropy. A three-dimensional numerical analysis was performed, selecting anisotropy index and dip angles as variables. The results showed that as the anisotropy index increased, the displacement in the tunnel increased, and stress concentration became more pronounced. The maximum displacement and shear stress were observed where the dip planes met the tunnel.

• Journal of Cardiovascular Imaging
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• v.30 no.3
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• pp.153-168
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• 2022

Recent studies have shown that sodium/glucose cotransporter 2 (SGLT2) inhibitors might exert favourable changes on cardiac parameters as observed on cardiovascular imaging. We conducted a systematic review and meta-analysis to determine the effects of SGLT2 inhibitors on cardiac imaging parameters. Four electronic databases (PubMed, Embase, Cochrane, Scopus) were searched for studies in which the effects of SGLT2 inhibitors on cardiac imaging parameters were examined. Studies in which a population was administered SGLT2 inhibitors and analysed by echocardiography and/or cardiac magnetic resonance (CMR) imaging were included. Random-effects pair-wise meta-analysis models were utilized to summarize the studies. A total of 11 randomized controlled trials was included with a combined cohort of 910 patients. Comparing patients receiving SGLT2 inhibitors with subjects receiving placebo, the mean change in CMR-measured left ventricular mass (LVM) was -3.87 g (95% confidence interval [CI], -7.77 to 0.04), that in left ventricular end-systolic volume (LVESV) was -5.96 mL (95% CI, -10.52 to -1.41) for combined LVESV outcomes, that in left atrial volume index (LAVi) was -1.78 mL/m² (95% CI, -3.01 to -0.55) for combined LAVi outcomes, and that in echocardiography-measured E/e' was -0.73 (95% CI, -1.43 to -0.03). Between-group differences were not observed in LVM and LVESV after indexation. The only between-group difference that persisted was for LAVi. Treatment with SGLT2 inhibitors resulted in reduction in LAVi and E/e' on imaging, indicating they might have an effect on outcomes associated with LV diastolic function.

• Clinical and Experimental Pediatrics
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• v.50 no.11
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• pp.1091-1096
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• 2007

Purpose : The of common carotid artery intima media thickness (IMT) is an acknowledged noninvasive marker for early atherosclerotic changes. We investigate whether common carotid IMT is different between obese and normal-weight children and also evaluate the relationships IMT with cardiovascular risk factors. Methods : We collected the clinical data (age, sex, pubertal stage, body mass index) and measured blood pressure, glucose, insulin, lipid profiles and adiponectin in 49 obese children (mean age, 12 years) and 24 nonobese children as controls. The control group was composed of 24 nonobese children of the same age, sex and pubertal stage. We measured the carotid IMT of all subjects by B-mode ultrasound with a 7.5-MHz linear transducer and analyzed. Results : Obese children demonstrated a significantly thicker intima media (mean, 0.34 mm, peak, 0.42 mm) compared to the control group (mean, 0.31 mm, peak, 0.38 mm, P<0.01). IMT was significantly correlated to the BMI (r=0.431, P<0.01), age (r=0.317, P<0.01), total cholesterol (r=0.377, P< 0.01), triglyceride (r=0.253, P<0.05) and low-density lipoprotein cholesterol (r=0.289, P<0.05). Serum adiponectin was significantly lower in obese children than in controls (11.2 ng/mL vs. 14.7 ng/mL, P<0.05) and negatively related with IMT (r=-0.267, P<0.05). Conclusion : Obesity is associated with increased carotid artery IMT in children. Our results suggest vascular changes in obesity seem to occur already in childhood and vascular ultrasonography may helpful for screening cardiovascular complications in obese children.

• Tuberculosis and Respiratory Diseases
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• v.63 no.3
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• pp.242-250
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• 2007

Background: Abnormal angiogenesis can induce hypoxia within a highly proliferating tumor mass, and these hypoxic conditions can in turn create clinical problems, such as resistance to chemotherapy. However, the mechanism by which hypoxia induces these changes has not yet been determined. Therefore, this study was conducted to determine how hypoxia induces changes in cell viability and extracellular microenvironments in an in vitro culture system using non-small cell lung cancer cells. Methods: The non-small cell lung cancer cell line, A549 was cultured in DMEM or RPMI-1640 media that contained fetal bovine serum. A decrease in the oxygen tension of the media that contained the culture was then induced in a hypoxia microchamber using a $CO_2-N_2$ gas mixture. A gas analysis and an MTT assay were then conducted. Results: (1) The decrease in oxygen tension was checked the anaerobic gas mixture for 30 min and then reoxygenation was induced by adding a 5% $CO_2-room$ air gas mixture to the chamber. (2) Purging with the anaerobic gas mixture was found to decrease the further oxygen tension of cell culture media. (3) The low oxygen tension resulted in a low pH, lactic acidosis and a decreased glucose concentration in the media. (4) The decrease in glucose concentration that was observed as a result of hypoxia was markedly different when different types of media were evaluated. (5) The decrease in oxygen tension inhibited proliferation of A549 cells. Conclusion: These data suggests that tumor hypoxia is associated with acidosis and hypoglycemia, which have been implicated in the development of resistance to chemotherapy and radiotherapy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5254-5260
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• 2012

The purpose of this study is to find the relationship between lumber Herniated Nuclesus Pulposus of specific part and fat infiltration in paraspinal muscle. Also we intended to find the relationship between Body Mass Index(BMI) and fat infiltration ratio in the lumber paraspinal muscle based on the sexes of patients. We conducted this study of patients who visited our hospital from May, 2010 to May, 2012. The subjects are composed of 40 patients(20 females and 20 males), who are 30 to 50 years old suffering from severe lumber herniated nuclesus pulposus, who had or were going to have operation treatment. BMI is measured through anthropometry of each patient and fat infiltration inside the muscle is estimated by measuring the cross section area of lumbar paraspinal muscle from mid-cross section of disc(L2-S1) and fat infiltration ratio. The data of this study are analyzed by independent t-test to figure out the difference of fat infiltration between male and female, and by paired sample T-test after getting mean and standard deviation to find the changes of fat infiltration of lumbar on each level. Also correlation analysis is done by setting age as a control variable to find the correlation between BMI and fat infiltration of the whole lumbar. As a result, we could get only the meaningful difference between the sexes on upper lumber part(L2-L3) while we couldn't find any significant difference in the rest of lumbar(L3-S1). Besides, the changes of fat infiltration ratio on each lumbar level increased rapidly from lumbar 3,4 to lumbar 4,5. We also found that there is no correlation between fat infiltration ratio of lumbar paraspinal muscle(L2-S1) and BMI.