• Nuclear Engineering and Technology
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• v.53 no.1
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• pp.216-233
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• 2021

In this work, Rhizophora spp. particleboard phantoms were made using SPI-based adhesives, modified with sodium hydroxide and itaconic acid polyamidoamine-epichlorohydrin (0, 5, 10, and 15 wt%). An X-ray computed tomography (CT) imaging system was used to ascertain the CT numbers and density distribution profiles of the particleboards. The SPI-based/NaOH/IA-PAE/Rhizophora spp. particleboard phantoms with 15 wt% IA-PAE addition level had the highest solid content, flexural strength, flexural modulus, and internal bonding strength of 36.06 ± 1.08%, 18.61 ± 0.38 Nmm^-2, 7605.76 ± 0.89 Nmm^-2, and 0.463 ± 0.053 Nmm^-2, respectively. The moisture content, mass density, water absorption, and dimensional stability were 6.93 ± 0.27%, 0.962 ± 0.037 gcm^-3, 22.36 ± 2.47%, and 10.90 ± 0.86%, respectively. The results revealed that the mass attenuation coefficients and effective atomic number values within the 16.59-25.26 keV photon energy region, were close to the calculated XCOM values in water, with a p-value of 0.077. Moreover, the CT images showed that the dissimilarities in the discrepancy of the profile density decreased as the IA-PAE concentrations increased. Therefore, these results support the appropriateness of the SPI-based/NaOH/IA-PAE/Rhizophora spp. particleboard with 15 wt% IA-PAE adhesive as a suitable tissue-equivalent phantom material for medical health applications.

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.244-254
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• 2018

Surface modified poly ${\text\tiny{L}}$-lactic acid (PLLA) samples with hydroxyapatite (HA), heparin and bone morphogenetic protein-2 (BMP-2) mediated by polydopamine (pDA) coating (PLLA/pDA/HA/Hep/BMP-2) were prepared, and their effects on the enhancements of bone formation and osseointegration were evaluated in vitro and in vivo as compared to PLLA, PLLA/pDA/HA, and PLLA/pDA/Hep/BMP-2. The changes in surface chemical compositions, morphologies and wettabilities were observed by X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM) and water contact angle measurements. Pre-coating of HA particles with pDA provided uniform and homogeneous anchoring of particles to PLLA surface. In addition, the strong ionic interaction between heparin and pDA led PLLA surface readily heparinized for loading of BMP-2. In vitro experiments revealed that the levels of alkaline phosphatase (ALP) activity, calcium deposition, and osteocalcin (OCN) gene expression were higher in MG-63 human osteosarcoma cell lines grown on PLLA/pDA/HA/Hep/BMP-2 than on control PLLA, PLLA/pDA/HA, and PLLA/pDA/Hep/BMP-2. In vivo studies using micro-computed tomography (micro-CT) also showed that PLLA/pDA/HA/Hep/BMP-2 screw exhibited greatest value of bone volume (BV) and bone volume/tissue volume (BV/TV) among samples. Histological evaluations with H&E and Von Kossa staining demonstrated that a combination of HA and BMP-2 contributed to the strong osseointegration.

• Pediatric Infection and Vaccine
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• v.28 no.2
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• pp.124-131
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• 2021

Cryptococcus neoformans is a fungus that primarily causes opportunistic infections in immunocompromised hosts. It can also cause various infections in immunocompetent patients. Pulmonary cryptococcosis involving the lymph node is relatively rare in immunocompetent patients. In this report, a previously healthy 17-year-old girl presented with high-grade fever and persistent cough. Chest X-ray and computed tomography (CT) scan revealed an anterior mediastinal conglomerate mass that expanded to the right supraclavicular area. Ultrasound-guided gun biopsy revealed histological evidence of cryptococcosis. Immunological screening tests did not identify immunodeficiency. She recovered completely with a combination therapy of amphotericin B and flucytosine for 2 weeks, followed by fluconazole for 8 months. The characteristics of cryptococcosis involving the mediastinal lymph node and the lung should be understood, and the possibility of cryptococcosis even in immunocompetent hosts should be considered.

• Journal of the korean academy of Pediatric Dentistry
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• v.49 no.1
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• pp.57-64
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• 2022

Additional dentition images are needed because the dentitions are distorted in cone-beam computed tomography (CBCT) due to streak artifacts and non-uniformity of the x-ray beam. The purpose of this study is to evaluate the feasibility of improving the dentition image of CBCT scan with intraoral scanner instead of plaster models. Maxilla images from plaster models, two intraoral scanners, and CBCT of 20 patients aged 12 to 18 were used in this study. With one of the intraoral scanners, the full arch was scanned by three segments and combined into a complete full arch. Virtual skull-dentition hybrid images from intraoral scanners were superimposed with the images from plaster models to evaluate the coordinate value difference and distance at reference points. The results showed that the coordinate value difference and distance were smallest with segmented intraoral scan, which showed only 2 ㎛ distance. Intraoral scan may provide good dentition images for virtual skull-dentition images.

• Journal of radiological science and technology
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• v.45 no.4
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• pp.313-320
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• 2022

Both angiography and interventional procedures accompanied by angiography provide many diagnostic and therapeutic benefits to patients and are rapidly increasing. However, unlike general radiography or computed tomography using the same X-ray, the amount of radiation is quite high, but the dose range can vary considerably for each patient and operator. The high sensitivity of the lens to radiation during cerebral angiography and neurointervention is already well known, and although there are many related studies, it is insufficient to easily reduce radiation in diagnosis and treatment. In this situation, in particular, by adding three-dimensional rotational angiography (3D-RA) to the existing two-dimensional (2D) angiography, it is now possible to make an accurate diagnosis. However, since this 3D-RA acquires images through projection of more radiation than before, the exposure dose of the lens may be higher. Therefore, we tried to analyze whether the radiation dose of the lens can be reduced by moving the lens out of the field range by adjusting the table height and magnification ratio during the examination using 3D-RA. The surface dose was measured using a rando phantom and a radiophotoluminescent glass dosimeter (PLD) and the radiation dose was compared by adjusting the table height and magnification ratio based on the central point. As a result, it was found that the radiation dose of the lens decreased as the table height increased from the central point, that is, as the lens was out of the field of view. In conclusion, in 3D-RA, moving the table position of about 2 cm in height will make a significant contribution to the dose reduction of the lens, and it was confirmed that adjusting the magnification ratio can also reduce the surface dose of the lens.

• The Journal of Internal Korean Medicine
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• v.43 no.3
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• pp.477-484
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• 2022

Objective: The purpose of this study was to report the improvement effect of symptoms of integrative cancer treatment (ICT) on recurrent gallbladder cancer patients. Methods: A 73-year-old patient with recurrent gallbladder cancer visited the Daejeon Korean Medicine Hospital of Daejeon University East West Cancer Center (EWCC) on February 2022. After the diagnosis of gallbladder cancer, the patient underwent cholecystectomy and relapsed during follow-up. After the operation, the cancer recurred during follow-up, and after radiation treatment, she had been receiving ICT since February 2022. The clinical outcomes were measured by X-ray, computed tomography (CT), laboratory findings, including tumor markers (CEA, CA19-9), and numeric rating scales (NRS). Results: After treatment, abdominal pain was relieved from NRS 5 to 2, and abdominal circumference decreased from 74.5 to 67. During and after treatment, we found neither hepatotoxicity nor nephrotoxicity in the laboratory findings. Conclusion: This case study suggests that ICT may improve symptoms in patients with gallbladder cancer.

• Journal of Trauma and Injury
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• v.35 no.4
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• pp.248-254
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• 2022

Purpose: To analyze the data of trauma patients with undetected injuries at the time of initial resuscitation during the primary and secondary surveys. Methods: We retrospectively reviewed the medical records of 807 patients who were hospitalized at the National Trauma Center, Seoul, Korea from June 1, 2019 to June 30, 2021. Results: In trauma patients with an Injury Severity Score ≥16 accounted for 27.5% in the non-missed injury group (non-MIG), but this rate was considerably higher at 71.2% in MIG. The mean hospitalization longer in MIG (50.90±39.56) than in non-MIG (24.74±26.11). The proportion of patients with missed injuries detected through tertiary trauma survey (TTS) was 28 patients (23.5%) within 24 hours, 90 patients (75.6%) after 24 hours to before discharge. The majority of missed injuries were fractures (82.4%) and ligament tears (8.4%), which required consultation with the orthopedic department. The final diagnoses of missed injuries were confirmed by computed tomography (44.5%), magnetic resonance imaging (19.3%), X-ray (19.3%), bone scan (11.8%), and physical examination (5.0%). Conclusions: TTS is considered a useful process for detecting missed injuries that were not identified at the time of initial resuscitation in the primary and secondary surveys. In the future, to detect missed injuries quickly, it is necessary to develop a suitable TTS program for each trauma center. In addition, further research is needed to verify the effectiveness of the protocolized TTS and survey chart to improve the effectiveness of TTS.

• Clinics in Shoulder and Elbow
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• v.25 no.4
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• pp.288-295
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• 2022

Background: There is no standardized therapeutic strategy for locked posterior shoulder fracture-dislocation (PSFD), and no consensus exists on the analysis of preoperative factors. This retrospective study aimed to evaluate functional results and complications in a series of PSFD cases managed with open surgical treatment. Methods: Patients diagnosed with locked PSFD who underwent open surgical treatment with reduction and osteosynthesis between April 2016 and March 2020 were included. All participants were treated with open reduction and internal fixation. Functional assessment used the modified University of California, Los Angeles (UCLA) mod scale, American Shoulder and Elbow Surgeons (ASES) questionnaire, subjective shoulder value (SSV), and visual analog scale (VAS). Complications were evaluated clinically and radiologically by X-ray and computed tomography. Results: Twelve shoulders were included (11 patients; mean age, 40.6 years; range, 19- 62 years). The mean follow-up duration was 23.3 months (range, 12-63 months). The UCLA mod, ASES, SSV, and VAS scores were 29.1±3.7, 81.6±13.5, 78±14.8, and 1.2±1.4 points, respectively. The overall complication rate was 16.6%, with one case of post-traumatic stiffness, 1 case of chronic pain, and no cases of avascular necrosis. Conclusions: Open surgical treatment of locked PSFD can achieve good functional results. A correct understanding of these injuries and good preoperative planning helped us to achieve a low rate of complications.

• Journal of Periodontal and Implant Science
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• v.53 no.4
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• pp.248-258
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• 2023

Purpose: This study aimed to characterize the early stages of periodontal disease and determine the optimal period for its evaluation in a mouse model. The association between the duration of ligation and its effect on the dentogingival area in mice was evaluated using micro-computed tomography (CT) and histological analysis. Methods: Ninety mice were allocated to an untreated control group or a ligation group in which periodontitis was induced by a 6-0 silk ligation around the left second maxillary molar. Mice were sacrificed at 1, 2, 3, 4, 5, 8, 11, and 14 days after ligature placement. Alveolar bone destruction was evaluated using micro-CT. Histological analysis was performed to assess the immune-inflammatory processes in the periodontal tissue. Results: No significant difference in alveolar bone loss was found compared to the control group until day 3 after ligature placement, and a gradual increase in alveolar bone loss was observed from 4 to 8 days following ligature placement. No significant between-group differences were observed after 8 days. The histological analysis demonstrated that the inflammatory response was evident from day 4. Conclusions: Our findings in a mouse model provide experimental evidence that ligature-induced periodontitis models offer a consistent progression of disease with marginal attachment down-growth, inflammatory infiltration, and alveolar bone loss.

• Restorative Dentistry and Endodontics
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• v.46 no.4
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• pp.56.1-56.11
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• 2021

Objectives: This study evaluated 2 nickel-titanium rotary systems and a complementary protocol with an ultrasonic tip and a small-diameter instrument in flattened root canals. Materials and Methods: Thirty-two human maxillary second premolars with flattened canals (buccolingual diameter ≥4 times larger than the mesiodistal diameter) at 9 mm from the radiographic apex were selected. The root canals were prepared by ProDesign Logic (PDL) 30/0.01 and 30/0.05 or Hyflex EDM (HEDM) 10/0.05 and 25/0.08 (n = 16), followed by application of the Flatsonic ultrasonic tip in the cervical and middle thirds and a PDL 25/0.03 file in the apical third (FPDL). The teeth were scanned using micro-computed tomography before and after the procedures. The percentage of volume increase, debris, and uninstrumented surface area were analyzed using the Kruskal-Wallis, Dunn, Wilcoxon, analysis of variance/Tukey, and paired and unpaired t-tests (α = 0.05). Results: No significant difference was found in the volume increase and uninstrumented surface area between PDL and HEDM (p > 0.05). PDL had a higher percentage of debris than HEDM in the middle and apical thirds (p < 0.05). The FPDL protocol resulted in less debris and uninstrumented surface area for PDL and HEDM (p < 0.05). This protocol, with HEDM, reduced debris in the middle and apical thirds and uninstrumented surface area in the apical third (p < 0.05). Conclusions: High percentages of debris and uninstrumented surface area were observed after preparation of flattened root canals. The HEDM, Flatsonic tip, and 25/0.03 instrument protocol enhanced cleaning in flattened root canals.