OBJECTIVES: We estimated the population prevalence of antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including unreported infections, through a Korea Seroprevalence Study of Monitoring of SARS-CoV-2 Antibody Retention and Transmission (K-SEROSMART) in 258 communities throughout Korea. METHODS: In August 2022, a survey was conducted among 10,000 household members aged 5 years and older, in households selected through two stage probability random sampling. During face-to-face household interviews, participants self-reported their health status, COVID-19 diagnosis and vaccination history, and general characteristics. Subsequently, participants visited a community health center or medical clinic for blood sampling. Blood samples were analyzed for the presence of antibodies to spike proteins (anti-S) and antibodies to nucleocapsid proteins (anti-N) SARS-CoV-2 proteins using an electrochemiluminescence immunoassay. To estimate the population prevalence, the PROC SURVEYMEANS statistical procedure was employed, with weighting to reflect demographic data from July 2022. RESULTS: In total, 9,945 individuals from 5,041 households were surveyed across 258 communities, representing all basic local governments in Korea. The overall population-adjusted prevalence rates of anti-S and anti-N were 97.6% and 57.1%, respectively. Since the Korea Disease Control and Prevention Agency has reported a cumulative incidence of confirmed cases of 37.8% through July 31, 2022, the proportion of unreported infections among all COVID-19 infection was suggested to be 33.9%. CONCLUSIONS The K-SEROSMART represents the first nationwide, community-based seroepidemiologic survey of COVID-19, confirming that most individuals possess antibodies to SARS-CoV-2 and that a significant number of unreported cases existed. Furthermore, this study lays the foundation for a surveillance system to continuously monitor transmission at the community level and the response to COVID-19.

Objective: The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are frequently prescribed medications worldwide for the treatment of hypercholesterolemia. Statins are considered to be well tolerated; however, they have a potential for myotoxicity. Concomitant drugs that inhibit cytochrome P450 3A4 can increase the concentration of statins and thus the risk of developing myotoxicity. The purpose of this study was to evaluate risk factors associated with potential drug-drug interactions in patients receiving statins. Methods: The subjects of this study were patients aged more than 18 years who received at least one prescription of statins in a general hospital located in Chuncheon-si, Korea, between January 1, 2018, and March 31, 2018. Data regarding statin use and baseline characteristics was collected from the computerized hospital database. Logistic regression analysis was used to identify risk factors associated with potential drug-drug interactions. Results: A total of 1061 patients were finally included in the study. The incidence of potential drug-drug interactions was 45% in all subjects. According to the results of the multivariate logistic regression analysis, myocardial infarction as the indication of statin, arrhythmia or heart failure as a comorbidity, and aspartate aminotransferase levels higher than 40 IU/L were significant risk factors for potential drug-drug interactions in study subjects. Diltiazem was the most commonly co-prescribed drug that caused potential drug-drug interactions with statins. Conclusion There was a considerable rate of potential drug-drug interactions in patients receiving statins. Health care professionals should attempt to reduce potential drug-drug interactions during statin administration.

Objective: The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are frequently prescribed medications worldwide for the treatment of hypercholesterolemia. Statins are considered to be well tolerated; however, they have a potential for myotoxicity. Concomitant drugs that inhibit cytochrome P450 3A4 can increase the concentration of statins and thus the risk of developing myotoxicity. The purpose of this study was to evaluate risk factors associated with potential drug-drug interactions in patients receiving statins. Methods: The subjects of this study were patients aged more than 18 years who received at least one prescription of statins in a general hospital located in Chuncheon-si, Korea, between January 1, 2018, and March 31, 2018. Data regarding statin use and baseline characteristics was collected from the computerized hospital database. Logistic regression analysis was used to identify risk factors associated with potential drug-drug interactions. Results: A total of 1061 patients were finally included in the study. The incidence of potential drug-drug interactions was 45% in all subjects. According to the results of the multivariate logistic regression analysis, myocardial infarction as the indication of statin, arrhythmia or heart failure as a comorbidity, and aspartate aminotransferase levels higher than 40 IU/L were significant risk factors for potential drug-drug interactions in study subjects. Diltiazem was the most commonly co-prescribed drug that caused potential drug-drug interactions with statins. Conclusion There was a considerable rate of potential drug-drug interactions in patients receiving statins. Health care professionals should attempt to reduce potential drug-drug interactions during statin administration.

BACKGROUND: Alopecia areata (AA) is an autoimmune skin disease difficult to manage and treat. The pathogenesis of AA features a T-cell-associated autoimmune process, and systemic immunosuppressive therapy is prescribed widely for AA. OBJECTIVE: To evaluate the efficacy and tolerance of systemic low-dose methotrexate (LD-MTX) therapy in treatment of recalcitrant AA multiplex. METHODS: In a retrospective, non-controlled study, we evaluated 29 patients with recalcitrant AA treated with LD-MTX and assessed the therapeutic response according to severity of disease, disease duration, cumulative dose of MTX, and drug safety. RESULTS: MTX was administered twice weekly, and the mean maximum weekly dose was 14.48 mg. The response was A5 (regrowth=100.0%) in 14 (48.3%) patients and A4 (regrowth of 75%~90%) in 12 (41.4%) patients. Three patients had poor response to LD-MTX treatment (A2: n=2 [6.9%], A1: n=1 [3.4%]). All three of the patients showing a poor response had disease durations exceeding 24 months. Relapse was observed in 31% of patients with more than 75% regrowth. Common side-effects were elevated liver enzyme levels and gastrointestinal discomfort. CONCLUSION: LD-MTX appears to be an effective and well-tolerated treatment for recalcitrant AA multiplex.
Alopecia Areata* ; Alopecia* ; Humans ; Liver ; Methotrexate* ; Recurrence ; Retrospective Studies ; Skin Diseases

PURPOSE: To investigate the care patterns for radiation therapy and to determine inter-hospital differences for patients with laryngeal carcinoma in Korea. MATERIALS AND METHODS: A total of 237 cases of laryngeal carcinoma (glottis, 144; supraglottis, 93) assembled from 23 hospitals, who underwent irradiation in the year of 1998 and 1999, were retrospectively analyzed to investigate inter-hospital differences with respect to radiotherapy treatment. We grouped the 23 hospitals based on the number of new patients annually irradiated in 1998; and designated them as group A (> or =900 patients), group B (> or =400 patients and <900 patients), and group C (<400 patients). RESULTS: The median age of the 237 patients was 62 years (range, 25 to 88 years), of which 216 were male and 21 were female. The clinical stages were distributed as follows: for glottis cancer, I; 61.8%, II; 21.5%, III; 4.2%, IVa; 11.1%, IVb; 1.4%, and in supraglottic cancer, I; 4.3%, II; 19.4%, III; 28.0%, IVa; 43.0%, IVb; 5.4%, respectively. Some differences were observed among the 3 groups with respect to the dose calculation method, radiation energy, field arrangement, and use of an immobilization device. No significant difference among 3 hospital groups was observed with respect to treatment modality, irradiation volume, and median total dose delivered to the primary site. CONCLUSION: This study revealed that radiotherapy process and patterns of care are relatively uniform in laryngeal cancer patients in Korean hospitals, and we hope this nationwide data can be used as a basis for the standardization of radiotherapy for the treatment of laryngeal cancer.
Female ; Glottis ; Humans ; Immobilization ; Korea ; Laryngeal Neoplasms ; Male ; Retrospective Studies

Splenic infarction caused by malaria is a rare complication and this is mostly caused by plasmodium falciparum. We report here on a 38 year-old female patient who developed symptomatic splenic infarction that was caused by vivax malaria. She presented with fever and left upper quadrant pain. Computed tomography showed multiple low density areas in the spleen, and the peripheral blood smear revealed plasmodium vivax infestation. We examined for other causes of splenic infarction, but all were negative. This is just the second report of symptomatic splenic infarction that was caused by vivax malaria only. Unlike the previous case, the levels of D-dimer and fibrinogen degradation factor were elevated. This may be related with the hypercoagulable state caused by malaria. Treatment was conservative and the further course was uneventful.
Female ; Fever ; Fibrin Fibrinogen Degradation Products ; Fibrinogen ; Humans ; Malaria ; Malaria, Vivax ; Plasmodium falciparum ; Plasmodium vivax ; Spleen ; Splenic Infarction

We evaluated on the calculation accuracy of treatment planning system (TPS) with phantom having convex and concave surface. The TPS is Eclipse (Varian, USA) using both algorithms AAA and PBC for photon dose calculations. PBC algorithms have three corrections of Batho, modified Batho (M-Batho), and equivalent TAR (E-TAR). The field sizes were 10x10 cm2 and 20x20 cm2, and MLC-shaped fields for these fields. We measured doses at three depths 5, 10 and 15 cm in phantom of SSD=90 cm in the condition of inserted farmer chamber. For given conditions, we have calculated dose with these algorithms and compared them with measured doses. In AAA the calculated doses (dose/MU) were agreed to measured doses within +/-1% in flat and convex surface and were under estimated with -1.9% maximum in concave surface. In PBC the calculated doses were over estimated with +1.7% and +4.1% respectively in flat and convex surface and the differences were from -3.1% to +2.1% in concave surface. In comparison of criteria from AAPM and IAEA reports, and statistical analysis for these results, it is found that the AAA's results are in good agreement with measured values and the M-Batho's results are generally good agreed with measured values among PBC algorithms.
Water

Stent thrombosis (ST) is one of the major complications that occur in percutaneous coronary interventions (PCIs) with stents. Various factors have been attributed to the development of ST, and several strategies have been recommended for its management. We report the case of a patient suffering from recurrent subacute STs after recurrent PCIs. The patient was treated by coronary artery bypass graft (CABG).
Coronary Artery Bypass ; Humans ; Percutaneous Coronary Intervention ; Stents ; Stress, Psychological ; Thrombosis ; Transplants

Monte Carlo calculations were performed to demonstrate the dose modulation with dynamic magnetic fields in phantom. The goal of this study is to obtain the uniform dose distributions at a depth region as a target on the central axis of photon beam under moving transverse magnetic field. We have calculated the depth dose curves for two cases of moving magnetic field along a depth line, constant speed and optimal speed. We introduced step-by-step shift and time factor of the position of the electromagnet as an approximations of continuous moving. The optimal time factors as a function of magnetic field position were calculated by least square methods using depth dose data for static magnetic field. We have verified that the flat depth dose is produced by varying the speed of magnetic field as a function of position as a results of Monte Carlo calculations. For 3 T magnetic field, the dose enhancement was 10.1% in comparison to without magnetic field at the center of the target.
Axis, Cervical Vertebra ; Magnetic Fields* ; Magnets ; Time Factors

In this work we have measured the dose distribution and the percent depth dose of 20 MeV electron beam using the X-OMAT films in order to verify the effects of transverse magnetic field on high energy elecrtron beam in a phantom. The result shows about 30% increase of the percent depth dose at 4.5 cm depth under the transverse magnetic field of 1.5 Tesla at 7.5 cm depth. We have verified that these were in an agreement with other theoretical results.
Magnetic Fields*