• Korean Journal of Radiology
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• v.20 no.8
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• pp.1266-1274
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• 2019

Objective: To determine whether radiologic extranodal extension (ENE) appearing on pretreatment CT and MRI could predict the prognosis in patients with human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (OPSCC). Materials and Methods: The study population was obtained from a historical cohort diagnosed with HPV-related OPSCC. A total of 134 OPSCC patients who had a metastatic lymph node on pretreatment CT or MRI were included, and radiologic ENE was evaluated by two experienced head and neck radiologists. Kaplan-Meier and multivariate Cox regression analyses were performed to evaluate the impact of radiologic ENE on progression-free survival (PFS). The diagnostic performance of CT and MRI for the diagnosis of ENE was also evaluated in patients who underwent neck dissection. Results: Seventy patients (52.2%) showed radiologic ENE-positive findings. Although patients showing radiologic ENE had a worse 3-year PFS (83.7% vs. 95.3%, p = 0.023), the association between radiologic ENE and PFS was not statistically significant on multivariate analysis (p = 0.141; hazard ratio, 2.68; 95% confidence interval, 0.72-9.97). CT or MRI had a sensitivity of 62%, specificity of 77.8%, and accuracy of 71.9% for predicting pathologic ENE. Conclusion: Radiologic ENE on CT or MRI did not predict poor PFS in patients with HPV-related OPSCC, although there was a trend towards worse PFS. Further studies are warranted to determine whether radiologic ENE is a useful imaging biomarker to risk-stratify patients with HPV-related OPSCC.

• The Korean Journal of Physiology and Pharmacology
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• v.28 no.1
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• pp.21-30
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• 2024

The challenging clinical outcomes associated with advanced cervical cancer underscore the need for a novel therapeutic approach. Monensin, a polyether antibiotic, has recently emerged as a promising candidate with anti-cancer properties. In line with these ongoing efforts, our study presents compelling evidence of monensin's potent efficacy in cervical cancer. Monensin exerts a pronounced inhibitory impact on proliferation and anchorage-independent growth. Additionally, monensin significantly inhibited cervical cancer growth in vivo without causing any discernible toxicity in mice. Mechanism studies show that monensin's anti-cervical cancer activity can be attributed to its capacity to inhibit the Wnt/β-catenin pathway, rather than inducing oxidative stress. Monensin effectively reduces both the levels and activity of β-catenin, and we identify Akt, rather than CK1, as the key player involved in monensin-mediated Wnt/β-catenin inhibition. Rescue studies using Wnt activator and β-catenin-overexpressing cells confirmed that β-catenin inhibition is the mechanism of monensin's action. As expected, cervical cancer cells exhibiting heightened Wnt/β-catenin activity display increased sensitivity to monensin treatment. In conclusion, our findings provide pre-clinical evidence that supports further exploration of monensin's potential for repurposing in cervical cancer therapy, particularly for patients exhibiting aberrant Wnt/β-catenin activation.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.27 no.2
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• pp.166-171
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• 2023

Backgrounds/Aims: Routine execution of intraoperative cholangiography (IOC) in laparoscopic cholecystectomy (LC) is considered a good practice to help early identification of biliary duct injuries (BDIs) or common bile duct (CBD) stones. This study aimed to determine the impact of IOC during LC. Methods: This is a retrospective, monocentric study, including patients with a LC performed from January 2020 to December 2021. Results: Of 303 patients, 215 (71.0%) were in the IOC group and 88 (29.0%) in the no-IOC group. IOC was incomplete or unclear in 10.7% of patients, with a failure rate of 14.7%. Operating time was 15 minutes longer in the IOC group (p = 0.01), and postoperative complications were higher (5.1% vs. 0.0%, p = 0.03). There were three BDIs (0.99%), all included in the IOC group; only one was diagnosed intraoperatively, and the other two were identified during the postoperative course. Regarding identifying CBD stones, IOC showed a sensitivity of 77%, a specificity of 98%, an accuracy of 97.2%, a positive predictive value of 63% and a negative predictive value of 99%. Conclusions: Systematic IOC has shown no specific benefits and prolonged operative duration. IOC should be performed on selected patients or in situations of uncertainty on the anatomy.

• Journal of Cardiovascular Imaging
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• v.31 no.4
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• pp.159-168
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• 2023

BACKGROUND: The gold standard for diagnosis of cardiac tumours is histopathological examination. Cardiovascular magnetic resonance (CMR) is a valuable non-invasive, radiation-free tool for identifying and characterizing cardiac tumours. Our aim is to understand CMR diagnosis of cardiac tumours by distinguishing benign vs. malignant tumours compared to the gold standard. METHODS: A systematic search was performed in the PubMed, Web of Science, and Scopus databases up to December 2022, and the results were reviewed by 2 independent investigators. Studies reporting CMR diagnosis were included in a meta-analysis, and pooled measures were obtained. The risk of bias was assessed using the Quality Assessment Tools from the National Institutes of Health. RESULTS: A total of 2,321 results was obtained; 10 studies were eligible, including one identified by citation search. Eight studies were included in the meta-analysis, which presented a pooled sensitivity of 93% and specificity of 94%, a diagnostic odds ratio of 185, and an area under the curve of 0.98 for CMR diagnosis of benign vs. malignant tumours. Additionally, 4 studies evaluated whether CMR diagnosis of cardiac tumours matched specific histopathological subtypes, with 73.6% achieving the correct diagnosis. CONCLUSIONS: To the best of our knowledge, this is the first published systematic review on CMR diagnosis of cardiac tumours. Compared to histopathological results, the ability to discriminate benign from malignant tumours was good but not outstanding. However, significant heterogeneity may have had an impact on our findings.

• Steel and Composite Structures
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• v.51 no.5
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• pp.509-527
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• 2024

Bonding carbon fiber-reinforced polymer (CFRP) laminates have been extensively employed in the restoration of steel constructions. In addition to the mechanical properties of the CFRP, the bond strength (P_U) between the CFRP and steel is often important in the eventual strengthened performance. Nonetheless, the bond behavior of the CFRP-steel (CS) interface is exceedingly complicated, with multiple failure causes, giving the P_U challenging to forecast, and the CFRP-enhanced steel structure is unsteady. In just this case, appropriate methods were established by hybridized Random Forests (RF) and support vector regression (SVR) approaches on assembled CS single-shear experiment data to foresee the P_U of CS, in which a recently established optimization algorithm named Aquila optimizer (AO) was used to tune the RF and SVR hyperparameters. In summary, the practical novelty of the article lies in its development of a reliable and efficient method for predicting bond strength at the CS interface, which has significant implications for structural rehabilitation, design optimization, risk mitigation, cost savings, and decision support in engineering practice. Moreover, the Fourier Amplitude Sensitivity Test was performed to depict each parameter's impact on the target. The order of parameter importance was t_c> L_c > E_A > t_A > E_c > b_c > f_c > f_A from largest to smallest by 0.9345 > 0.8562 > 0.79354 > 0.7289 > 0.6531 > 0.5718 > 0.4307 > 0.3657. In three training, testing, and all data phases, the superiority of AO - RF with respect to AO - SVR and MARS was obvious. In the training stage, the values of R² and VAF were slightly similar with a tiny superiority of AO - RF compared to AO - SVR with R² equal to 0.9977 and VAF equal to 99.772, but large differences with results of MARS.

• Journal of Microbiology and Biotechnology
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• v.34 no.6
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• pp.1222-1228
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• 2024

Protein-specific antibodies are essential for various aspects of protein research, including detection, purification, and characterization. When specific antibodies are unavailable, protein tagging is a useful alternative. Small epitope tags, typically less than 10 amino acids, are widely used in protein research due to the simple modification through PCR and reduced impact on the target protein's function compared to larger tags. The 2B8 epitope tag (RDPLPFFPP), reported by us in a previous study, has high specificity and sensitivity to the corresponding antibody. However, when attached to the C-terminus of the target protein in immunoprecipitation experiments, we observed a decrease in detection signal with reduced immunity and low protein recovery. This phenomenon was not unique to 2B8 and was also observed with the commercially available Myc tag. Our study revealed that C-terminal tagging of small epitope tags requires the addition of more than one extra amino acid to enhance (restore) antibody immunities. Moreover, among the amino acids we tested, serine was the best for the 2B8 tag. Our findings demonstrated that the interaction between a small epitope and a corresponding paratope of an antibody requires an extra amino acid at the C-terminus of the epitope. This result is important for researchers planning studies on target proteins using small epitope tags.

• Journal of Microbiology and Biotechnology
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• v.34 no.6
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• pp.1229-1238
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• 2024

This study aimed to develop and assess a chitosan biomedical antibacterial gel ZincOxide-GrapheneOxide/Chitosan/β-Glycerophosphate (ZnO-GO/CS/β-GP) loaded with nano-zinc oxide (ZnO) and graphene oxide (GO), known for its potent antibacterial properties, biocompatibility, and sustained drug release. ZnO nanoparticles (ZnO-NPs) were modified and integrated with GO sheets to create 1% and 3% ZnO-GO/CS/β-GP thermo-sensitive hydrogels based on ZnO-GO to Chitosan (CS) mass ratio. Gelation time, pH, structural changes, and microscopic morphology were evaluated. The hydrogel's antibacterial efficacy against Porphyromonas gingivalis, biofilm biomass, and metabolic activity was examined alongside its impact (MC3T3-e1). The findings of this study revealed that both hydrogel formulations exhibited temperature sensitivity, maintaining a neutral pH. The ZnO-GO/CS/β-GP formulation effectively inhibited P. gingivalis bacterial activity and biofilm formation, with a 3% ZnO-GO/CS/β-GP antibacterial rate approaching 100%. MC3T3-e1 cells displayed good biocompatibility when cultured in the hydrogel extract.The ZnO-GO/CS/β-GP thermo-sensitive hydrogel demonstrates favorable physical and chemical properties, effectively preventing P. gingivalis biofilm formation. It exhibits promising biocompatibility, suggesting its potential as an adjuvant therapy for managing and preventing peri-implantitis, subject to further clinical investigations.

• Journal of the Korean Institute of Gas
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• v.28 no.2
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• pp.47-55
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• 2024

More than 100 liquefied hydrogen tanks are expected to be introduced in Korea by 2030. Since liquefied hydrogen is stored in a vacuum insulation structure tank at -253℃, there is a possibility of a major disaster in which the tank bursts if there is a problem with insulation. Therefore, the law stipulates that PRV should be installed as the last bastion. It is important to note that in the case of liquefied hydrogen, it becomes useless if the pressure drop of the pipe is ignored and the capacity is calculated incorrectly. In CGA S-1.3, the pressure drop rate of the PRV inlet and outlet pipes is set to less than 3% and less than 10%, respectively. However, there is an interdependence between the amount of pressure drop and the flow rate of the pipe, making it impossible to calculate these values at once. Therefore, we developed a simulator that calculates the pressure loss rate of PRV system using MATLAB/Simulink and evaluated the sensitivity of the pressure drop rate to design elements.

• Nutrition Research and Practice
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• v.18 no.4
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• pp.498-510
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• 2024

BACKGROUND/OBJECTIVES: Obesity, characterized by abnormal fat accumulation and metabolic disturbances, presents a significant health challenge. Opuntia humifusa Raf., commonly known as Korean Cheonnyuncho, is rich in various beneficial compounds and has demonstrated antioxidant and anti-inflammatory effects. However, its potential impact on glucose and lipid metabolism, particularly in obese rats, remains unexplored. We aimed to investigate whether O. humifusa stems and fruits could beneficially alter glucose metabolism and lipid profiles in a rat model of high-fat diet (HFD)-induced obesity. MATERIALS/METHODS: Thirty-two rats were allocated into 4 groups: normal diet (NF), HFD control (HF), HFD treated with 2% O. humifusa stems (HF-OS), and HFD treated with 2% O. humifusa fruits (HF-OF). Experimental diets were administered for 6 weeks. At the end of the treatment, liver and fat tissues were isolated, and serum was collected for biochemical analysis. The major flavonoid from O. humifusa stems and fruits was identified and quantified. RESULTS: After 6 weeks of treatment, the serum fasting glucose concentration in the HF-OS group was significantly lower than that in the HF group. Serum fasting insulin concentrations in both HF-OS and HF-OF groups tended to be lower than those in the HF group, indicating a significant improvement in insulin sensitivity in the HF-OS group. Additionally, the HF-OS group exhibited a tendency towards the restoration of adiponectin levels to that of the NF group. CONCLUSION: The 2% O. humifusa stems contain abundant quercetin and isorhamnetin, which alter fasting blood glucose levels in rats fed a HFD, leading to a favorable improvement in insulin resistance.

• Coupled systems mechanics
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• v.13 no.4
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• pp.293-310
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• 2024

This paper investigates the dynamic response of structures during earthquakes and provides a clear understanding of soil-structure interaction phenomena. It analyses various parameters, comprising ground shear wave velocity and structure properties. The effect of soil impedance function form on the structural response of the system through the use of springs and dashpots with two frequency cases: independent and dependent frequencies. The superstructure and the ground were modeled linearly. Using the substructure method, two different approaches are used in this study. The first is an analytical formulation based on the dynamic equilibrium of the soil-structure system modeled by an analog model with three degrees of freedom. The second is a numerical analysis generated with 2D finite element modeling using ABAQUS software. The superstructure is represented as a SDOF system in all the SSI models assessed. This analysis establishes the key parameters affecting the soil-structure interaction and their effects. The different results obtained from the analysis are compared for each studied case (frequency-independent and frequency-dependent impedance functions). The achieved results confirm the sensitivity of buildings to soil-structure interaction and highlight the various factors and effects, such as soil and structure properties, specifically the shear wave velocity, the height and mass of the structure. Excitation frequency, and the foundation anchoring height, also has a significant impact on the fundamental parameters and the response of the coupled system at the same time. On the other hand, it have been demonstrated that the impedance function forms play a critical role in the accurate evaluation of structural behavior during seismic excitation. As a result, the evaluation of SSI effects on structural response must take into account the dynamic properties of the structure and soil accordingly.