National cohort data collected during the coronavirus disease 2019 (COVID-19) delta and omicron periods in Korea revealed a lower risk of severe infection in recipients of three doses of the COVID-19 vaccine (adjusted odds ratio [aOR], 0.05–0.08). The risk of death was reduced during the omicron period compared to the delta period (aOR, 0.75; 95% confidence interval, 0.67–0.84).

Objectives: : We estimated the overall and age-specific percentages of the Korean population with presumed immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as of April 2022 using the national registry. Methods: : We used the national coronavirus disease 2019 (COVID-19) infection and vaccination registry from South Korea, as described to define individuals with a previous history of COVID-19 infection, vaccination, or both, as persons with presumed immunity. Results: : Of a total of 53,304,627 observed persons, 24.4% had vaccination and infection, 58.1% had vaccination and no infection, 7.6% had infection and no vaccination, and 9.9% had no immunity. The SARS-CoV-2 Omicron variant emerged at a time when the presumed population immunity ranged from 80% to 85%; however, nearly half of the children were presumed to have no immunity. Conclusion : We report a gap in population immunity, with lower presumed protection in children than in adults. The approach presented in this work can provide valuable informed tools to assist vaccine policy-making at a national level.

Background/Aims: Direct‐acting antivirals (DAAs) have been approved for hepatitis C virus (HCV) treatment in patients with end-stage renal disease (ESRD) on hemodialysis. Nevertheless, the complicated comedications and their potential drug-drug interactions (DDIs) with DAAs might limit clinical practice in this special population. Methods: The number, class, and characteristics of comedications and their potential DDIs with five DAA regimens were analyzed among HCV-viremic patients from 23 hemodialysis centers in Taiwan. Results: Of 2,015 hemodialysis patients screened in 2019, 169 patients seropositive for HCV RNA were enrolled (mean age, 65.6 years; median duration of hemodialysis, 5.8 years). All patients received at least one comedication (median number, 6; mean class number, 3.4). The most common comedication classes were ESRD-associated medications (94.1%), cardiovascular drugs (69.8%) and antidiabetic drugs (43.2%). ESRD-associated medications were excluded from DDI analysis. Sofosbuvir/velpatasvir/voxilaprevir had the highest frequency of potential contraindicated DDIs (red, 5.6%), followed by glecaprevir/pibrentasvir (4.0%), sofosbuvir/ledipasvir (1.3%), sofosbuvir/velpatasvir (1.3%), and elbasvir/grazoprevir (0.3%). For potentially significant DDIs (orange, requiring close monitoring or dose adjustments), sofosbuvir/velpatasvir/voxilaprevir had the highest frequency (19.9%), followed by sofosbuvir/ledipasvir (18.2%), glecaprevir/pibrentasvir (12.6%), sofosbuvir/velpatasvir (12.6%), and elbasvir/grazoprevir (7.3%). Overall, lipid-lowering agents were the most common comedication class with red-category DDIs to all DAA regimens (n=62), followed by cardiovascular agents (n=15), and central nervous system agents (n=10). Conclusions HCV-viremic patients on hemodialysis had a very high prevalence of comedications with a broad spectrum, which had varied DDIs with currently available DAA regimens. Elbasvir/grazoprevir had the fewest potential DDIs, and sofosbuvir/velpatasvir/voxilaprevir had the most potential DDIs.

The heterogeneity of cancer makes it difficult to predict the prognosis of treatment. There is still a lack of preclinical model systems that reflect the clinical characteristics of patients who have heterogenetic tumors. Advances in 3-dimentional (3D) cell culture are leading to discoveries that occur in the development and progression of cancer that has not been known. There are many models including patient-derived xenograft, patient-derived organoid and spheroid, patient-derived explant, scaffold-based model, and system-based model. Each 3D model has its strengths and limitations. One model cannot answer every question, so it seems most reasonable to approach multiple models when studying cancer heterogeneity. Hopefully, 3D tumor modeling will make tremendous progress on this path by fusion of innovative biomaterials and advanced modeling techniques that can partially mimic the heterogeneous environment of real tumors.

In November 2021, 14 international travel-related severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B.1.1.529 (omicron) variant of concern (VOC) patients were detected in South Korea. Epidemiologic investigation revealed community transmission of the omicron VOC. A total of 80 SARS-CoV-2 omicron VOC-positive patients were identified until December 10, 2021 and 66 of them reported no relation to the international travel.There may be more transmissions with this VOC in Korea than reported.

Objectives: . The loss of signal during intraoperative neuromonitoring (IONM) using electromyography (EMG) in thyroidectomy is one of the biggest problems. We have developed a novel IONM system with an endotracheal tube (ETT) with an attached pressure sensor instead of EMG to detect laryngeal twitching. The aim of the present study was to investigate the feasibility and reliability of this novel IONM system using an ETT with pressure sensor during thyroidectomy in a porcine model. Methods: . We developed an ETT-attached pressure sensor that uses the piezoelectric effect to measure laryngeal muscle twitching. Stimulus thresholds, amplitude, and latency of laryngeal twitching evaluated using the pressure sensor were compared to those measured using transcartilage needle EMG. The measured amplitude changes by EMG and the pressure sensor during recurrent laryngeal nerve (RLN) traction injury were compared. Results: . No significant differences in stimulus threshold intensity between EMG and the pressure sensor were observed. The EMG amplitude detected at 0.3 mA, increased with increasing stimulus intensity. When the stimulus was more than 1.0 mA, the amplitude showed a plateau. In a RLN traction injury experiment, the EMG amplitude did not recover even 20 minutes after stopping RLN traction. However, the pressure sensor showed a mostly recovery. Conclusion . The change in amplitude due to stimulation of the pressure sensor showed a pattern similar to EMG. Pressure sensors can be feasibly and reliably used for RLN traction injury prediction, RLN identification, and preservation through the detection of laryngeal muscle twitching. Our novel IONM system that uses an ETT with an attached pressure sensor to measure the change of surface pressure can be an alternative to EMG in the future.

PURPOSE: Wide-neck aneurysms (WNAs) associated with a dilated parent artery (PA) are not uncommon morphological abnormalities and usually cause inappropriate wall apposition and incomplete neck coverage of a tubular stent in stent-assisted coiling of aneurysms. We aimed to introduce a fusiform-shaped stent (FSS) and test its effectiveness in treating intracranial WNAs associated with a dilated PA using a three-dimensional (3D) model. MATERIALS AND METHODS: Two FSS types were designed with the middle one-third segment dilated by 10% (FSS10) and 20% (FSS20) and were compared with the tubular-shaped stent (TSS). A patient-specific 3D WNA model was prototyped and produced, and in vitro stent placement was performed. Angiographic images of the three stent types were analyzed and compared using predetermined parameters. RESULTS: The stent lumens were significantly larger in FSS10 and FSS20 than in TSS in the middle segments (P=0.046), particularly FSS20 (P=0.018). The non-covered area at the ostium tended to be smaller in FSS10 and FSS20 than in TSS, but the difference was not significant (P>0.05). The stent length was significantly longer in FSS10 and FSS20 than in TSS. The stent cell size was significantly larger in FSS than in TSS. CONCLUSION: Better vessel wall apposition and aneurysmal neck coverage was observed for FSS than for TSS. No significant difference was observed between FSS10 and FSS20.
Aneurysm ; Arteries ; Cell Size ; Endovascular Procedures ; Humans ; In Vitro Techniques* ; Intracranial Aneurysm* ; Neck ; Parents ; Stents*

Methanol poisoning results in neurological complications including visual disturbances, bilateral putaminal hemorrhagic necrosis, parkinsonism, cerebral edema, coma, or seizures. Almost all reported cases of methanol poisoning are caused by oral ingestion of methanol. However, recently there was an outbreak of methanol poisoning via non-oral exposure that resulted in severe neurological complications to a few workers at industrial sites in Korea. We present 3 patients who had severe neurological complications resulting from non-oral occupational methanol poisoning. Even though initial metabolic acidosis and mental changes were improved with hemodialysis, all of the 3 patients presented optic atrophy and ataxia or parkinsonism as neurological complications resulting from methanol poisoning. In order to manage it adequately, as well as to prevent it, physicians should recognize that methanol poisoning by non-oral exposure can cause neurologic complications.
Acidosis ; Ataxia ; Brain Diseases, Metabolic ; Brain Edema ; Coma ; Eating ; Humans ; Korea ; Methanol* ; Necrosis ; Neurologic Manifestations ; Optic Atrophy ; Parkinsonian Disorders ; Poisoning* ; Renal Dialysis ; Seizures

BACKGROUND: Flecainide is an antiarrhythmic agent that is used primarily in the treatment of cardiac arrhythmias. Some evidences also suggest that flecainide can participate in alveolar fluid clearance and inflammatory responses. This experiment was aimed to evaluate the effects of flecainide on sepsis induced acute lung injury in a rat model. METHODS: Rats were treated with subcutaneous infusion of saline or flecainide (0.1 or 0.2 mg/kg/hr) by a mini-osmotic pump. Subcutaneous infusion was started 3 hours before and continued until 8 hours after intraperitoneal injection of saline or endotoxin. Animals were sacrificed for analyses of severity of acute lung injury with wet to dry (W/D) ratio and lung injury score (LIS) in lung and inflammatory responses with level of leukocyte, polymorphonuclear neutrophils (PMNs) and inteleukin-8 (IL-8) in bronchoalveolar lavages fluid (BALF). RESULTS: Flecainide markedly improved dose dependently sepsis induced acute lung injury as analysed by W/D ratio (from 2.24 ± 0.11 to 1.76 ± 0.09, p < 0.05) and LIS (from 3 to 1, p < 0.05), and inflammatory response as determined by leukocyte (from 443 ± 127 to 229 ± 95, p < 0.05), PMNs (from 41.43 ± 17.63 to 2.43 ± 2.61, p < 0.05) and IL-8 (from 95.00 ± 15.28 to 40.00 ± 10.21, p < 0.05) in BALF. CONCLUSIONS: Flecanide improve sepsis induced acute lung injury in rats by controlling inflammatory responses.
Acute Lung Injury* ; Animals ; Arrhythmias, Cardiac ; Bronchoalveolar Lavage ; Flecainide* ; Infusions, Subcutaneous ; Injections, Intraperitoneal ; Interleukin-8 ; Leukocytes ; Lung ; Lung Injury ; Models, Animal ; Neutrophils ; Rats ; Sepsis*