Objective: This study evaluates the impact of the coronavirus disease 2019 (COVID-19) pandemic on emergency medical service (EMS) responses and out-of-hospital cardiac arrest (OHCA) outcomes. Methods: This is a retrospective comparison study analyzing the OHCA data of a university medical center in Seoul during the COVID-19 pandemic period (January 2020-January 2021) and non-pandemic period (January 2019-January 2020). The EMS response time and OHCA outcomes were compared between both periods. Based on the weekly mean number of confirmed cases and their EMS response time, patients were classified into six groups and OHCA outcomes were compared. Results: This study evaluated 309 OHCA patients (non-pandemic period of 146, pandemic period of 163). Significant delays in the EMS response and transport time were observed during the pandemic period. However, no significant differences were obtained in the rate of return of spontaneous circulation (ROSC) and survival at discharge (12.4% in pandemic vs. 13.8% in non-pandemic; P=0.722). According to the weekly mean COVID-19 incidence when patients were over 100, there was a significant increase in the EMS response and transport time, whereas ROSC and survival rate were dramatically decreased. Conclusion During the pandemic, the EMS service for OHCA patients was worse than before, with delayed and reduced survival for OHCA patients. We further determined that an increase in the number of COVID-19 cases (especially when weekly mean numbers were over 100) dramatically delayed the EMS response time. This resulted in a very low survival rate of OHCA patients.

Objective: Acute renal infarction is a rare and easily misdiagnosed disease. Scarce research has been conducted on the predictive factors and prognosis of acute renal infarction due to its rarity. In this study, we analyzed the clinical and laboratory findings of a patient diagnosed with renal infarction to predict clinical outcomes. Methods: In this retrospective clinical study, we collected and analyzed the medical records data of 61 acute renal infarction patients diagnosed in the emergency department (ED) of Konkuk University Hospital, Seoul, South Korea from January 2007 to December 2020. Results: Lactate dehydrogenase (LDH; 93.3%, 28 of 30 patients) and D-dimer (77.8%, 28 of 36 patients) levels of the acute renal infarction patients were higher than the normal. Proteinuria was found in 26 of 47 patients. The only significant prognostic factor for the occurrence of acute kidney injury (AKI) in acute renal infarction is the ratio of the infarction volume to the total renal volume. Age, occurrence of AKI, and proteinuria were correlated with the progression of chronic kidney disease (CKD). Conclusion The ratio of the infarction volume to the total renal correlated with occurance of AKI. Age, AKI, and proteinuria were correlated with the progression of CKD.

The programmed cell death ligand 1 (PD-L1) and its receptor programmed cell death 1 (PD-1) deliver inhibitory signals to regulate immunological tolerance during immune-mediated diseases. However, the role of PD-1 signaling and its blockade effect on human dental pulp stem cells (hDPSCs) differentiation into the osteo-/odontogenic lineage remain unknown. We show here that PD-L1 expression, but not PD-1, is downregulated during osteo-/odontogenic differentiation of hDPSCs. Importantly, PD-L1/PD-1 signaling has been shown to negatively regulate the osteo-/odontogenic differentiation of hDPSCs. Mechanistically, depletion of either PD-L1 or PD-1 expression increased ERK and AKT phosphorylation levels through the upregulation of Ras enzyme activity, which plays a pivotal role during hDPSCs osteo-/odontogenic differentiation. Treatment with nivolumab (a human anti-PD-1 monoclonal antibody), which targets PD-1 to prevent PD-L1 binding, successfully enhanced osteo-/odontogenic differentiation of hDPSCs through enhanced Ras activity-mediated phosphorylation of ERK and AKT. Our findings underscore that downregulation of PD-L1 expression accompanies during osteo-/odontogenic differentiation, and hDPSCs-intrinsic PD-1 signaling inhibits osteo-/odontogenic differentiation. These findings provide a significant basis that PD-1 blockade could be effective immunotherapeutic strategies in hDPSCs-mediated dental pulp regeneration.
B7-H1 Antigen/metabolism* ; Dental Pulp/metabolism* ; Humans ; Programmed Cell Death 1 Receptor/metabolism* ; Regeneration ; Stem Cells

Objective: In the coronavirus disease 2019 pandemic, virus transmission via exposal to arrest victims infected can be a huge risk to rescuers during cardiopulmonary resuscitation (CPR). We hypothesized that using a mechanical chest compression device can reduce the rescuer’s exposure to cardiac arrest patients during CPR. Methods: This is a retrospective clinical study that compared CPRs using a mechanical chest compression device (mCPR) with CPRs with manual chest compression (c-CPR). All CPR data were obtained by analyzing recorded video clips and the medical charts. The primary outcome was the number of rescuers who participated in CPR. In addition, the length of time rescuers’ staying around the arrested victim and some procedure time were evaluated. Results: There was no significant difference in baseline data of CPR between the m-CPR (n=28) and c-CPR (n=25) groups. The m-CPR group showed a significantly reduced mean number of rescuers (4.4±0.5 vs. 5.5±0.5) and mean total time of rescuer’s staying (2,609.9±315.4 seconds vs. 3,286.0±329.9 seconds) comparing with the c-CPR group (P<0.05). The m-CPR group showed a delay in the first rhythm analysis compared with the c-CPR group (40.0 seconds [30.0-57.5] vs. 27.0 seconds [25.0-43.5]) Conclusion The usage of a mechanical compression device can reduce the number of rescuers and the length of time staying around the victim. However, a delay in rhythm analysis can occur in the m-CPR group.

Objective: This study aimed to evaluate the effectiveness of video laryngoscopy (VL; Glidescope) compared to direct laryngoscopy (DL) when performing endotracheal intubation (ETI) in trauma patients with cervical spine immobilization. Methods: This was a retrospective clinical study. A total of 98 trauma patients with cervical spine immobilization were included. These patients underwent intubation using VL and DL from 2009 to 2014 in the emergency department. All data were collected through electronic medical records. The primary outcome was the first-attempt intubation success rate of ETI. Secondary outcomes were complications of ETI, including esophageal intubation and tooth injuries. We compared the outcomes of the two devices. Results: VL showed higher first-attempt ETI success rates compared to DL (94.0% vs. 74.5%, P=0.011). There were no statistically significant differences in the ETI complication rates between VL and DL such as esophageal intubation (2.0% vs. 4.3%, P=0.610) and tooth injuries (6.0% vs. 10.6%, P=0.478). The multivariate analysis showed that VL was an independent factor for predicting higher first-attempt intubation success with an odds ratio of 4.538 (95% confidence interval, 1.084-18.988; P=0.038) Conclusion For patients with cervical spine immobilization, VL could provide a higher first-attempt ETI success rate compared to DL in a real clinical setting.

Objectives: . Thyroid cancer is the most common endocrine tumor, with rapidly increasing incidence worldwide. However, its transcriptomic characteristics associated with immunological signatures, driver fusions, and recurrence markers remain unclear. We aimed to investigate the transcriptomic characteristics of advanced papillary thyroid cancer. Methods: . This study included 282 papillary thyroid cancer tumor samples and 155 normal samples from Chungnam National University Hospital and Seoul National University Hospital. Transcriptomic quantification was determined by high-throughput RNA sequencing. We investigated the associations of clinical parameters and molecular signatures using RNA sequencing. We validated predictive biomarkers using the Cancer Genome Atlas database. Results: . Through a comparison of differentially expressed genes, gene sets, and pathways in papillary thyroid cancer compared to normal tumor-adjacent tissue, we found increased immune signaling associated with cytokines or T cells and decreased thyroid hormone synthetic pathways. In addition, patients with recurrence presented increased CD8+ T-cell and Th1-cell signatures. Interestingly, we found differentially overexpressed genes related to immune-escape signaling such as CTLA4, IDO1, LAG3, and PDCD1 in advanced papillary thyroid cancer with a low thyroid differentiation score. Fusion analysis showed that the PI3K and mitogen-activated protein kinase (MAPK) signaling pathways were regulated differently according to the RET fusion partner genes (CCDC6 or NCOA4). Finally, we identified HOXD9 as a novel molecular biomarker that predicts the recurrence of thyroid cancer in addition to known risk factors (tumor size, lymph node metastasis, and extrathyroidal extension). Conclusion . We identified a high association with immune-escape signaling in the immune-hot group with aggressive clinical characteristics among Korean thyroid cancer patients. Moreover, RET fusion differentially regulated PI3K and MAPK signaling depending on the partner gene of RET, and HOXD9 was found to be a recurrence marker for advanced papillary thyroid cancer.

Objective: : Osteoporosis result from age-related decline in the number of osteoblast progenitors in the bone marrow. Probiotics have beneficial effects on the host, when administered in appropriate amounts. This study investigated the effects of probiotics expressing specific genes, especially the effects of genetically modified bone morphogenetic protein (BMP)-2-expressing Lactobacillus plantarum CJNU 3003 (LP) on ovariectomized rats. Methods: : Twenty-eight female Wistar rats (250–300 g, 12 weeks old) were divided into four groups : the sham (control), the ovariectomy (OVX)-induced osteoporosis group (OVX), the OVX and LP (OVX/LP), OVX and genetically modified BMP-2-expressing LP (OVX/LP with BMP) groups. The three groups underwent bilateral OVX and two of these groups were administered two different types of LP via oral gavage daily. At 16 weeks post-OVX, blood was collected from the heart and the bilateral tibiae were extracted and were scanned by ex-vivo micro-computed tomography and stained with hematoxylin-and-eosin (H&E) and Masson’s trichrome stain for pathological assessment. The serum levels of osteocalcin (OC), rat C-telopeptide of type I collagen (CTX-I), BMP-2, and receptor activator of nuclear factor-ĸB ligand (RANKL) were measured. Results: : The 3D-micro-computed tomography images showed that the trabecular structure in the OVX/LP with BMP group was maintained compared with OVX and OVX/LP groups. No significant differences were detected in trabecular thickness (Tb.Th) between control and OVX/LP with BMP groups (p>0.05). Furthermore, a tendency toward increased BMD, trabecular bone volume, Tb.Th, and trabecular number and decreased trabecular separation was found in rats in the OVX/LP with BMP groups when compared with the OVX and OVX/LP groups (p>0.05). The H&E and Masson’s trichrome stained sections showed a thicker trabecular bone in the OVX/LP with BMP group compared with the OVX and OVX/LP groups. There was no difference in serum levels of OC, CTX and RANKL control and OVX/LP with BMP groups (p>0.05). In contrast, significant differences were found in OC and CTX-1 levels between the OVX and OVX/LP with BMP groups (p<0.05). Conclusion : Our results showed that the expression of genetically modified BMP-2 showed inhibition effect for bone loss in a rat model of osteoporosis.

Objective: The study compared the first-attempt success and complication rates of endotracheal intubation (ETI) using video laryngoscopy (VL; GlideScope) with those of direct laryngoscopy (DL) in the emergency department (ED). Methods: This was a retrospectively clinical study of adult patients who underwent intubation using from 2010 to 2014 in the ED. All data were collected from the electronic medical records. The primary outcome was the first-attempt intubation success of ETI. The secondary outcomes were occurrences of desaturation, hypotension, oesophageal intubation, dental injuries, and cardiac arrest. The between-device differences in outcome risks were examined. Results: A total of 431 emergency ETIs were included. The first-attempt intubation success rate was higher in the VL than DL (93.8% vs. 74.8%, P<0.001). The non-expert emergency physicians (first and second-year residents) showed a higher first-attempt intubation success rate in VL than DL, but there was no difference in the first-attempt intubation success rate between the two devices between experts (third and fourth-year residents). The use of VL was associated with a lower rate of desaturation (0.0% vs. 5.0%) and tooth injuries (0.0% vs. 2.7%) compared to the DL. Conclusion The use of VL was associated with a higher first-attempt success rate compared to DL, particularly in inexperienced intubators. For complications related to ETI, VL showed a lower rate of desaturation and dental injuries in the ED than the DL.