Objective: The 2020 Cardiopulmonary Resuscitation (CPR) guidelines recommend the use of feedback devices during CPR training and do not limit their use in actual CPR. Although there have been various studies on metronome-assisted CPR that use a metronome as a feedback device, there are no research results to determine a specific metronome setting rate. We analyzed the quality of CPR and the effectiveness of the metronome feedback according to the metronome setting rate within the recommended chest compression rate range. Methods: Fifty healthcare providers who had received CPR training or had performed CPR in the previous 2 years participated, and all of them performed CPR at three rates (100/min, 110/min, and 120/min). The CPR was performed for 2 minutes with only chest compressions. The smartphone metronome (Metronome version 13.0 Android, KHTSXR, Seoul, Korea) application was used for the rate setting, and Resusci Anne QCPR Mk II (Laerdal Medical, Stavanger, Norway) was used to measure the CPR quality. The difference in the CPR quality according to the setting rate was analyzed. Results: There was no significant difference in the “average compression depth (mm),” “adequate compression depth ratio (%),” and “adequate release ratio (%)” at the three set rates. The “adequate compression rate ratio (%)” was 98.48±5.27% at 110/min, which was higher than that at 120/min or 100/min, and this was a statistically significant difference (P=0.000). There was no significant difference in the “adequate compression site ratio (%).” Conclusion When performing metronome-assisted CPR, setting the rate to 110/min can more appropriately maintain the recommended chest compression rate range and can result in high-quality CPR.

Background: Although an inverse association between the N-terminal prohormone brain natriuretic peptide (NT-proBNP) and obesity exists, only few major studies have assessed the association between NT-proBNP levels and skeletal muscle mass in asymptomatic healthy adults. Therefore, this cross-sectional study was conducted. Methods: We assessed participants who underwent health examinations at Kangbuk Samsung Hospital in South Korea from January 2012 to December 2019. Appendicular skeletal muscle mass was measured using a bioelectrical impedance analyzer, and the skeletal muscle mass index (SMI) was calculated. Participants were divided into the control, mildly low skeletal muscle mass (LMM) (−2 standard deviation [SD] < SMI ≤−1 [SD]), and severely LMM groups (SD ≤−2) based on their SMI. The association between elevated NT-proBNP level (≥125 pg/mL) and skeletal muscle mass was assessed using multivariable logistic regression analysis with adjustment for confounding factors. Results: This study enrolled 15,013 participants (mean age, 37.52±9.52; men, 54.24%; control, n=12,827; mildly LMM, n=1,998; severely LMM, n=188). Prevalence of elevated NT-proBNP was higher in mildly and severely LMM groups than in the control group (control, 1.19%; mildly LMM, 1.4%; severely LMM, 4.26%; P=0.001). The adjusted odds ratio (OR) of elevated NT-proBNP was significantly higher in severely LMM (OR, 2.87; 95% confidence interval [CI], 1.3 to 6.37) than in control (OR, 1.00; reference) or mildly LMM groups (OR, 1.24; 95% CI, 0.81 to 1.89). Conclusion Our results showed that NT-proBNP elevation were more prevalent in participants with LMM. In addition, our study showed an association between skeletal muscle mass and NT-proBNP level in a relatively young and healthy adult population.

In this study, the Ti6Al4V specimens were fabricated using selective laser melting (SLM) method (Ti6Al4V-AS group). These specimens were performed to heat treatment at 950℃ and 550℃ using vacuum electric furnace (Ti6Al4V-HT group). The mechanical properties, metallographic shape, crystalline structure, and chemical compositions of the alloy specimens before and after heat treatment were analyzed. The Ti6Al4V-AS group showed ultimate tensile strength (UTS) and low elongation values. Acicular crystal grains were observed in metallographic image and the α'-Ti phase was dominant. After heat treatment (Ti6Al4V-HT group), the UTS was lowered and the elongation was increased. In addition, a lamellar structure in which columnar crystal grains are arranged was observed, α+β-Ti phase was formed, and crystallinity increased. As a result of analyzing the chemical composition, the Ti6Al4V-AS specimen contained a higher carbon content than the Ti6Al4V-HT specimen. This high carbon content could be related to the formation of α'-phase, high strength and low elongation of the Ti6Al4V-AS specimen. Ti6Al4V-HT specimen showed that the overall carbon content was low, but the carbon content was locally high in the α-Ti phase region. Therefore, it is necessary to control effectively the incorporation of carbon gas in the production of Ti6Al4V specimens using SLM.

Objective: The assessment of cortical integrity following renal injuries with planar Tc-99m dimercaptosuccinic acid (DMSA) scintigraphy depends on measuring relatively decreased cortical uptake (i.e., split renal function [SRF]). We analyzed the additive values of the volumetric and quantitative analyses of the residual cortical integrity using single-photon emission computed tomography (SPECT) compared to the planar scintigraphy. Materials and Methods: This prospective study included 47 patients (male:female, 32:15; age, 47 ± 22 years) who had nonoperatively managed renal injuries and underwent DMSA planar and SPECT imaging 3–6 months after the index injury. In addition to planar SRF, SPECT SRF, cortical volume, and absolute cortical uptake were measured for the injured kidney and both kidneys together. The correlations of planar SRF with SPECT SRF and those of SRF with volumetric/quantitative parameters obtained with SPECT were analyzed. The association of SPECT parameters with renal function, grades of renal injuries, and the risk of renal failure was also analyzed. Results: SPECT SRF was significantly lower than planar SRF, with particularly higher biases in severe renal injuries. Planar and SPECT SRF (dichotomized with a cutoff of 45%) showed 19%–36% of discrepancies with volumetric and quantitative DMSA indices (when dichotomized as either high or low). Absolute cortical uptake of the injured kidney best correlated with glomerular filtration rate (GFR) at follow-up (ρ = 0.687, P < 0.001) with significant stepwise decreases by GFR strata (90 and 60 mL/min/1.73 m2 ). Total renal cortical uptake was significantly lower in patients with moderate-to-high risk of renal failure than those with low risk. However, SRF did not reflect GFR decrease below 60 mL/min/1.73 m2 or the risk of renal failure, regardless of planar or SPECT (count- or volume-based SRF) imaging. Conclusion Quantitative measurements of renal cortical integrity assessed with DMSA SPECT can provide more clinically relevant and comprehensive information than planar imaging or SRF alone.

While the coronavirus disease 2019 pandemic is ongoing, monkeypox has been rapidly spreading in non-endemic countries since May 2022. Accurate and rapid laboratory tests are essential for identifying and controlling monkeypox. Korean Society for Laboratory Medicine and the Korea Disease Prevention and Control Agency have proposed guidelines for diagnosing monkeypox in clinical laboratories in Korea. These guidelines cover the type of tests, selection of specimens, collection of specimens, diagnostic methods, interpretation of test results, and biosafety. Molecular tests are recommended as confirmatory tests. Skin lesion specimens are recommended for testing in the symptomatic stage, and the collection of both blood and oropharyngeal swabs is recommended in the presymptomatic or prodromal stage.

Objective: Easy-to-understand information on emergency patient transportation and emergency medical resources is required to operate emergency medical resources appropriately. This study evaluated emergency patient transport routes using a geographic information system (GIS) and converted them into visual information to understand the current status of emergency medical resource use in the region. Methods: The basic data used in this study were collected from the 119 safety centers in Gangwon-do, South Korea, under the fire-fighting headquarters in Gangwon-do from January 2017 to December 2020. The data were analyzed using the geographic information system and converted to visual information. Results: The number of patients with cardiovascular disease, cerebrovascular disease, and traffic accidents was 12,944. Of these, 9,393 patients (72.6%) were transported from Chuncheon city, and 3,551 patients (27.4%) were transported out of Chuncheon city. The number of patients with cardiovascular diseases during the study period was 1,219 (9.4%); 782 patients (64.2%) were transported to the K-EMC (emergency medical center), and 437 patients (35.8%) were transported to the H-EMC. For cerebrovascular disease, 913 patients (7.1%) were transported to the EMC of Chuncheon city, with 585 (64.1%) K-EMC and 328 (35.9%) H-EMC patients. The number of traffic accident patients was 1,266 (9.8%). Five hundred and forty (42.7%) and 726 (57.3%) patients were transported to the K-EMC and H-EMC, respectively. Conclusion The adequacy of facilities, equipment, and human resources required to treat cardiac and cerebrovascular diseases in K-EMC and severe trauma in H-EMC needs to be reviewed.

The targeting of DNA methylation in cancer using DNA hypomethylating drugs has been well known to sensitize cancer cells to chemotherapy and immunotherapy by affecting multiple pathways. Herein, we investigated the combinational effects of DNA hypomethylating drugs and ionizing radiation (IR) in human sarcoma cell lines both in vitro and in vivo. Clonogenic assays were performed to determine the radiosensitizing properties of two DNA hypomethylating drugs on sarcoma cell lines we tested in this study with multiple doses of IR. We analyzed the effects of 5-aza-dC or SGI-110, as DNA hypomethylating drugs, in combination with IR in vitro on the proliferation, apoptosis, caspase-3/7 activity, migration/invasion, and Western blotting using apoptosis- or autophagy-related factors. To confirm the combined effect of DNA hypomethylating drugs and IR in our in vitro experiment, we generated the sarcoma cells in nude mouse xenograft models. Here, we found that the combination of DNA hypomethylating drugs and IR improved anticancer effects by inhibiting cell proliferation and by promoting synergistic cell death that is associated with both apoptosis and autophagy in vitro and in vivo. Our data demonstrated that the combination effects of DNA hypomethylating drugs with radiation exhibited greater cellular effects than the use of a single agent treatment, thus suggesting that the combination of DNA hypomethylating drugs and radiation may become a new radiotherapy to improve therapeutic efficacy for cancer treatment.

Purpose: Erlotinib has been the only targeted agent to show significantly improved outcomes in pancreatic adenocarcinoma when combined with gemcitabine. We aimed to evaluate whether the addition of oxaliplatin to a combination gemcitabine/erlotinib treatment conferred a clinical benefit in patients with locally advanced unresectable or metastatic pancreatic cancer. Materials and Methods: Chemotherapy-naïve patients with locally advanced or metastatic pancreatic cancer were randomly assigned to receive GEMOX-T [gemcitabine 1000 mg/m2 and oxaliplatin 50 mg/m2 on day 1 (D1) and D8 plus erlotinib 100 mg daily for 3 weeks] or GT (gemcitabine 1000 mg/m2 on D1 and D8 plus erlotinib 100 mg daily for 3 weeks). The primary endpoint was the overall response rate (ORR). Results: Between 2013 and 2016, 65 patients were assigned to a treatment group (33 in the GEMOX-T arm, 32 in the GT arm). The ORR was 18.2% [95% confidence interval (CI), 8.82–27.58] in the GEMOX-T arm and 6.2% (95% CI, 0.34–12.06) in the GT arm (p=0.051). The disease control rate was significantly superior in the GEMOX-T arm compared to the GT arm (72.7% vs. 43.8%, p=0.019). After a median follow-up of 19.7 months, the median progression-free survival (PFS) was 3.9 months for the GEMOX-T arm and 1.4 months for the GT arm (p=0.033). However, this did not translate to an improvement in overall survival. The most common grade 3 or higher hematologic adverse events were neutropenia (16.9%) and anemia (13.8%). Conclusion The addition of oxaliplatin to a first-line gemcitabine/erlotinib regimen demonstrated higher response rates and significantly improved PFS in patients with locally advanced or metastatic pancreatic cancer.

Objective: The number of elderly patients in Korea has been on the rise recently, and hence the number of out-of-hospital cardiac arrest (OHCA) elderly patients is also rising. The causes of cardiac arrest for the elderly vary, and, it is difficult to predict the recovery of spontaneous circulation (ROSC) in OHCA patients. Therefore, the purpose of this study was to ascertain the predictive value of arterial blood gas analysis (ABGA) results in achieving ROSC in the elderly. Methods: A retrospective analysis of emergency department patients with OHCA was performed at the Kangwon National University Hospital, Korea from 1 January 2016 to 31 December 2019. The initial ABGA results were compared between two patient groups, those who had achieved a return of spontaneous circulation and those who had not. Univariate and multivariable analyses were performed to elucidate the factors associated with ROSC. Results: Overall, 229 OHCA patients were included in the final analysis. The lactate level was independently related to ROSC. A receiver operating characteristics (ROC) curve was plotted to obtain the best cutoff value. The lactate level <9.85 mmol/L showed the largest area under the ROC curve (AUC) to predict ROSC (AUC, 0.666; 95% confidence interval, 0.588-0.743). Multiple regression analysis was performed using the cutoff value, which was a lactate level of 9.85 (odds ratio, 2.907; 95% confidence interval, 1.432-5.902; P=0.003). Conclusion The ABGA results during the cardiopulmonary resuscitation of OHCA patients, showed that the lactate level was an independent factor associated with ROSC. The lactate cutoff value was 9.85 mmol/L.

Objective: The number of elderly patients in Korea has been on the rise recently, and hence the number of out-of-hospital cardiac arrest (OHCA) elderly patients is also rising. The causes of cardiac arrest for the elderly vary, and, it is difficult to predict the recovery of spontaneous circulation (ROSC) in OHCA patients. Therefore, the purpose of this study was to ascertain the predictive value of arterial blood gas analysis (ABGA) results in achieving ROSC in the elderly. Methods: A retrospective analysis of emergency department patients with OHCA was performed at the Kangwon National University Hospital, Korea from 1 January 2016 to 31 December 2019. The initial ABGA results were compared between two patient groups, those who had achieved a return of spontaneous circulation and those who had not. Univariate and multivariable analyses were performed to elucidate the factors associated with ROSC. Results: Overall, 229 OHCA patients were included in the final analysis. The lactate level was independently related to ROSC. A receiver operating characteristics (ROC) curve was plotted to obtain the best cutoff value. The lactate level <9.85 mmol/L showed the largest area under the ROC curve (AUC) to predict ROSC (AUC, 0.666; 95% confidence interval, 0.588-0.743). Multiple regression analysis was performed using the cutoff value, which was a lactate level of 9.85 (odds ratio, 2.907; 95% confidence interval, 1.432-5.902; P=0.003). Conclusion The ABGA results during the cardiopulmonary resuscitation of OHCA patients, showed that the lactate level was an independent factor associated with ROSC. The lactate cutoff value was 9.85 mmol/L.