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The demand for aquaculture is increasing, but production is declining due to high feed costs and disease outbreaks. Viral hemorrhagic septicemia (VHS) is a viral disease that seriously affects seawater and freshwater fish in aquaculture, including the olive flounder (Paralichthys olivaceus), a major aquaculture fish in Korea. However, very few vaccines are currently available for viral hemorrhagic septicemia virus (VHSV). The nutrient-rich microalga Chlorella vulgaris has been used as a feed additive in aquaculture and as a host for the industrial production of recombinant VHSV glycoprotein as an oral vaccine. In this study, VHSV glycoprotein was cloned with a salt-inducible promoter, and high levels of expression up to 41.1 mg/g wet C. vulgaris, representing 27.4% of total extracted soluble protein, were achieved by growing the transformed C. vulgaris for 5 days in the presence of 250 mM NaCl. The production of a neutralizing antibody was detected in the serum of fish given feed containing 9% VHSV glycoprotein-expressing C. vulgaris. Furthermore, relative survival rates of 100% and 81.9% were achieved following challenges of these fish with VHSV at 106 and 107 pfu/fish, respectively, indicating that C. vulgaris could be used as a platform for the production of recombinant proteins for use as oral vaccines in the control of viral diseases in aquaculture. [ABSTRACT FROM AUTHOR]

Sex disparities have been reported in the prehospital and in-hospital care among patients with out-of-hospital cardiac arrest (OHCA). The aim of this study was to investigate the association between sex and prehospital advanced cardiac life support (ACLS) interventions provided by emergency medical services (EMS). This was a cross-sectional observational study using a nationwide OHCA registry in South Korea. The study included adult OHCAs with presumed cardiac etiology from January 2016 to December 2019. The main exposure was the sex of the victim, and the primary outcomes were prehospital ACLS interventions, including advanced airway management (AAM), intravenous access (IV), and epinephrine (EPI) administration. Multivariable logistic regression analysis accounted for age group, health insurance, comorbidities, place of arrest, urbanization level, witness status, bystander CPR and initial rhythm was performed to calculate adjusted odds ratios (AORs) with 95% confidence intervals (95% CIs). Among 71,154 eligible patients, females with OHCA received less prehospital ACLS interventions than males: risk difference, (95% CIs) −2.76 (-3.41;-2.11) for AAM, −6.03 (-6.79;-5.27) for IV, and −3.81 (-4.37;-3.25) for EPI. In multivariable logistic regression analysis, female sex was significantly associated with a lower probability of prehospital ACLS provision: AOR, (95% CIs) 0.87 (0.84-0.91) for AAM, 0.85 (0.82-0.88) for IV, and 0.81 (0.77-0.84) for EPI. Compared to male patients, female patients were less likely to receive prehospital ACLS. This offers opportunities for EMS systems to reduce disparities and to improve compliance with OHCA resuscitation guidelines and outcomes through quality improvement and educational interventions. [ABSTRACT FROM AUTHOR]

Objective: Spontaneous hemorrhagic stroke is a devastating disease with high mortality and grave neurological outcomes worldwide. This study aimed to evaluate the association between the elapsed time from emergency department (ED) visit to emergency neurosurgery and clinical outcomes in patients with spontaneous hemorrhagic stroke. Methods: A nationwide cross-sectional study was conducted using the nationwide emergency database in Korea. Spontaneous hemorrhagic stroke patients who received neurosurgery within 12 hours of ED visit between January 2018 and December 2019 were enrolled. The main exposure was time to neurosurgery and the primary outcome was in-hospital mortality. Multivariable logistic regression was conducted. Results: Among 2,602 study populations (incidence rate: 2.5 per 100,000 person-years, 15.8% of SAH, 78.6% of ICH, and 5.6% of mixed type), 525 (20.2%) patients received surgery in the ultra-early (0–2 hours) group, 1,093 (42.0%) in the early (2–4 hours) group, and 984 (37.8%) in the late (4–12 hours) group. The early group showed better survival outcomes than the ultra-early and late group (in-hospital mortality 22.2% vs. 26.5% and 26.1%, p = 0.06). Compared to the late group, adjusted OR (95% CI) for in-hospital mortality was 0.78 (0.63–0.96) for the early group, while there was no significant difference in the ultra-early group (0.90 (0.69–1.16)). Conclusions: Early neurosurgery within 2–4 hours of the ED visit was associated with favorable survival outcomes in patients with spontaneous hemorrhagic stroke. [ABSTRACT FROM AUTHOR]

Objectives: The case volume effects of ambulance stations on the survival of out-of-hospital cardiac arrest (OHCA) patients are uncertain. This study was conducted to evaluate the association between the case volume of ambulance stations and clinical outcomes in OHCAs by the number of emergency medical services (EMS) providers at the scene.Methods: Adult cardiac EMS-treated OHCAs between 2015 and 2018 were enrolled. The main exposure was the annual OHCA case volumes of 204 ambulance stations in Korea, which were categorized into three groups; low-volume (<100), moderate-volume (100-159) and high-volume (≥160). The primary and secondary outcomes were good neurological recovery and survival to discharge. Multilevel multivariable logistic regression analysis was conducted to calculate adjusted odds ratios (AORs). Interaction analysis between the number of EMS providers at the scene and the exposure variable was performed.Results: A total of 92,534 patients were enrolled. OHCAs in the low-volume group tended to be arrest in a public place or a non-metropolitan area, less prehospital administration of an advanced airway and intravenous management. Significant differences were found the main analysis: AORs (95% CIs) compared to the low-volume group were 1.15 (1.03-1.29) and 1.14 (1.03-1.27) in the high-volume and moderate-volume groups for good neurological recovery and 1.19 (1.07-1.33) and 1.14 (1.04-1.25) in the high-volume and moderate-volume groups for survival to discharge. Significant interaction effects between the number of EMS providers at the scene and case volume on clinical outcomes were found.Conclusion: OHCA case volumes of ambulance stations are associated with clinical outcomes after cardiac arrest. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to examine whether county socioeconomic status (SES) is associated with emergency medical service (EMS) response time and dual dispatch response of out-of-hospital cardiac arrest (OHCA) patients using county property tax per capita in Korea.Methods: All EMS-treated adults who suffered OHCAs were enrolled between 2015 and 2017, excluding cases witnessed by EMS providers. The main exposure was property tax per capita in the county where the OHCA occurred. The primary outcome was response time interval, with a secondary outcome of dual dispatch response. Negative binomial regression analysis to calculate incidence rate ratio (IRR) with a 95% confidence interval (CI) was conducted for EMS response time. A multivariable logistic regression analysis for response time interval (<8 min) and dual dispatch response was also conducted.Results: A total of 71,326 patients in 228 counties were enrolled. Compared to the lowest SES quartile, OHCA patients in the highest SES quartile had shorter median (interquartile range [IQR]) response time intervals (9.5 [5.9] minutes vs. 7.6 [4.2] minutes, IRR [95% CI] 0.95 [0.94-0.96], respectively). The AOR (95% CI) for response time within 8 min was 1.07 (1.01-1.13) for the highest SES quartile compared to the lowest SES quartile. Those in the highest SES quartile also had higher rates of dual dispatch response compared to those in the lowest quantile (50.9% vs 26.6%; AOR [95% CI]: 2.16 [2.03-2.30]).Conclusion: In OHCA patients, those in a lower SES are associated with longer response times and lower dual dispatch response. [ABSTRACT FROM AUTHOR]

Aims. High-risk carotid plaque remains an important risk factor for atherosclerotic cardiovascular disease (ASCVD). We sought to evaluate the characteristics of carotid plaque and to find out the predictors for high-risk carotid plaque in asymptomatic Koreans. Methods. Subjects (n = 801) without a history of ASCVD from 12 university hospitals in Korea underwent carotid ultrasound. The images were standardized at core laboratory. Morphologic characteristics of plaque were analyzed with laboratory and clinical characteristics. High-risk carotid plaque features included the highest quartile of carotid plaque score (cPS), irregular plaque surface, and hypoechoic and ulcerated plaque. Results. The carotid plaque prevalence was 22.1% (177/801 persons, 293 plaques). The plaque was increased with age (p < 0.001) and conventional ASCVD risk estimator (p < 0.001) and the most frequently found in bulb (n = 190 , 64.8%). The number of the highest quartile of cPS was 44/177 (24.9%). Irregular plaque was seen in 20.8% out of total plaque (61/293) and was more frequent in the high-risk 10-year ASCVD risk group than in the low-risk group (36.1% vs. 15.8%, p = 0.023). Hypoechoic and ulcerated plaques were seen in 14.3% (42/293) and 2% (6/293), respectively. The independent predictors for high-risk plaque were age (β = 0.052 , p < 0.001), HbA1c (β = 0.182 , p = 0.004), male (β = 0.118 , p = 0.006), hypertension (β = 0.090 , p = 0.032), and multiple plaques (OR: 4.810 (two plaques) and 8.621 (three plaques), all p < 0.001). Conclusions. This study suggests that high-risk carotid plaque was seen in 12.4% (99/801). The high-risk plaque was associated with diabetes control status reflected by the HbA1c level as well as traditional risk factors in asymptomatic Korean population. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to investigate the association between coronary angiography (CAG) with and without percutaneous coronary intervention (PCI) after out-of-hospital cardiac arrest (OHCA) and neurological recovery and to determine the influence of primary electrocardiogram or patient age on the effects of CAG. Methods: Adult patients with OHCA with cardiac etiology who were admitted to PCI-capable hospitals from 2016 to 2017 were enrolled in this study from the nationwide OHCA registry of Korea. Coronary intervention was categorized into three groups: No CAG, CAG without PCI, and CAG with PCI. The endpoint was good neurological recovery. Multivariable logistic regression and interaction analyses (intervention × electrocardiogram and intervention × age) were conducted by calculating adjusted odds ratios (aORs) and 95% confidence intervals (CI). Results: Of a total of 6,802 eligible OHCA patients, 1,218 (17.9%) underwent CAG without PCI and 1,136 (16.7%) underwent CAG with PCI. The CAG without PCI and CAG with PCI groups were more likely to have good neurological recovery than the No CAG group (57.4% vs. 61.6% vs. 16.3%; 3.39 [2.83–4.06] for CAG without PCI and 3.32 [2.74–4.01] for CAG with PCI). Interaction analysis showed that although the effect size differed according to patient characteristics, both CAG groups were associated with an increased likelihood of good neurological recovery, regardless of primary electrocardiogram and age group. In younger patients, CAG with PCI had greater outcome benefits than CAG without PCI (8.54 [4.31–16.95] vs. 4.10 [2.69–6.24]), whereas CAG without PCI had a larger effect size than CAG with PCI in elderly patients (4.46 [2.59–7.68] vs. 2.92 [1.80–4.73]) (p value for interaction 0.02). Conclusions: Post-resuscitation CAG with and without PCI are associated with better neurological recovery in patients with OHCA, regardless of primary electrocardiogram and patient age. [ABSTRACT FROM AUTHOR]

Viral hemorrhagic septicemia virus (VHSV) has been a main cause of morbidity and mortality in cultured olive flounder (Paralichthys olivaceus) in Korea. The aim of the present study was to construct recombinant baculovirus-based VHSV G protein delivery tools for the immunization of olive flounder. We rescued recombinant A. californica multiple nucleopolyhedrovirus (AcMNPV) i) displaying VHSV G protein on the viral envelop, ii) harboring a CMV promoter-driven VHSV G protein gene cassette, or iii) having a bicistronic construct equipped with both envelope-spiked G protein and a CMV promoter driven G protein cassette. In the immunization experiment, groups of olive flounder immunized with recombinant baculoviruses carrying VHSV G protein on the envelope showed significantly higher survival rates than groups of fish in the control group (medium only) and the control recombinant baculovirus (expressing green florescent protein) immunized group, suggesting the possible use of recombinant baculoviruses carrying foreign antigens on the envelope for the development of fish vaccines. The survival rate of fish immunized with a recombinant baculovirus having a CMV-driven VHSV G protein expressing cassette was higher than that of fish immunized with a baculovirus having a reporter protein-expressing cassette, but was much lower compared to previously reported results of VHSV G protein-based DNA vaccines, suggesting that the delivery efficiency of the present baculovirus-mediated VHSV G protein gene into olive flounder cell's nucleus might not be high compared to plasmid-based DNA vaccines. Although the group of fish immunized with the recombinant baculovirus equipped with both envelope-spiked G protein and a CMV promoter driven G protein cassette showed the highest survival rate against VHSV challenge, further elaborate studies are needed to uncover the synergic effect of the two forms of VHSV G protein delivered by recombinant baculoviruses. • Recombinant baculoviruses harboring or expressing VHSV G protein were rescued. • Baculovirus with VHSV G protein on envelope induced higher protection in olive flounder. • Baculovirus with CMV promoter-driven VHSV G protein induced a weak protection. • Baculovirus can be used as a delivery vehicle of antigens or genes for fish vaccination. [ABSTRACT FROM AUTHOR]

Early risk stratification of out-of-hospital cardiac arrest (OHCA) patients with insufficient information in emergency departments (ED) is difficult but critical in improving intensive care resource allocation. This study aimed to develop a simple risk stratification score using initial information in the ED. Adult patients who had OHCA with medical etiology from 2016 to 2020 were enrolled from the Korean Cardiac Arrest Research Consortium (KoCARC) database. To develop a scoring system, a backward logistic regression analysis was conducted. The developed scoring system was validated in both external dataset and internal bootstrap resampling. A total of 8240 patients were analyzed, including 4712 in the development cohort and 3528 in the external validation cohort. An ED-PLANN score (range 0–5) was developed incorporating 1 point for each: P for serum pH ≤ 7.1, L for serum lactate ≥ 10 mmol/L, A for age ≥ 70 years old, N for non-shockable rhythm, and N for no-prehospital return of spontaneous circulation. The area under the receiver operating characteristics curve (AUROC) for favorable neurological outcome was 0.93 (95% CI, 0.92–0.94) in the development cohort, 0.94 (95% CI, 0.92–0.95) in the validation cohort. Hosmer–Lemeshow goodness-of-fit tests also indicated good agreement. The ED-PLANN score is a practical and easily applicable clinical scoring system for predicting favorable neurological outcomes of OHCA patients. [ABSTRACT FROM AUTHOR]

Introduction: Alcohol intake is one of the triggers of out-of-hospital cardiac arrest (OHCA) and is associated with survival outcomes due to its relationship with cardiovascular conditions such as variant angina and arrhythmias. The aim of this study was to evaluate the association between alcohol intake shortly before cardiac arrest and survival outcomes after OHCA.Methods: This observational study was conducted using a nationwide OHCA registry database in Korea. All adult OHCA patients with presumed cardiac etiology from 2016 to 2019 were analyzed. The primary outcome was survival to hospital discharge. Secondary outcomes included coronary angiography (CAG), percutaneous coronary intervention (PCI), and implantable cardioverter-defibrillator (ICD) implantation. Groups with and without alcohol intake shortly before cardiac arrest were compared using propensity score matching and conditional logistic regression analysis.Results: Among the study population of 83,087, 1,777 (2.1%) patients consumed alcohol shortly before OHCA. In the propensity score-matched population, the group with alcohol intake showed significantly higher odds of survival to hospital discharge compared to the group without alcohol intake (OR (95% CI): 1.33 (1.15-1.53)). The odds of receiving CAG without PCI and ICD implantation were significantly higher in the group with alcohol intake compared to the group without alcohol intake (OR (95% CI): 1.60 (1.34-1.92) and 1.74 (1.28-2.37), respectively), while the odds of receiving CAG with PCI were significantly lower (OR (95% CI): 0.75 (0.59-0.95)).Conclusion: In OHCA patients with presumed cardiac etiology, alcohol intake shortly before arrest was associated with higher odds of survival outcomes. [ABSTRACT FROM AUTHOR]

Abstract Rhabdoviral G protein-based DNA vaccines have been recognized as a useful way to protect cultured fish from rhabdoviral diseases. In Korea, viral hemorrhagic septicemia virus (VHSV) genotype IVa has been the primary culprit of high mortalities of cultured olive flounder (Paralichthys olivaceus). In this study, we inserted a miR-155-expressing cassette into the VHSV's G protein-based DNA vaccine, and analyzed the effects of miR-155 on the antiviral activity and on the vaccine efficacy in olive flounder. Olive flounder fingerlings were intramuscularly (i.m.) immunized with 10 μg/fish (1st experiment) or 1 μg/fish (2nd experiment) of DNA vaccine plasmids. However, there were no significant differences in mortalities and serum neutralization titers between fish immunized with 1 μg and 10 μg plasmids/fish, suggesting that i.m. injection with 1 μg plasmids/fish would be enough to induce effective adaptive immune responses in olive flounder fingerlings. In survival rates, as fish immunized with just G protein expressing plasmids showed no or too low mortalities, the adjuvant effect of miR-155 was not discernible. Also, in the serum neutralization activities, although G gene or G gene plus miR-155 expressing DNA vaccines induced significantly higher activities than control vaccines (PBS and vacant vector), no significant differences were found between G gene alone and G gene plus miR-155 expressing DNA vaccines. In the serum virucidal activity, fish immunized with G gene plus miR-155 expressing DNA vaccine showed significantly higher activity against hirame rhabdovirus (HIRRV) at 3 days post-immunization (d.p.i.) compared to other groups, suggesting that miR-155 produced from the vector can enhance innate immune responses in olive flounder. The significantly enhanced serum virucidal activities against VHSV especially at 28 d.p.i. in the groups immunized with G gene alone and G gene plus miR-155 expressing DNA vaccines reflect the increased antibodies against G protein, which could activate the classical complement pathway and subsequent viral inactivation. As the available information on the DNA vaccines in olive flounder is not sufficient, more diverse researches on the protective efficacy of DNA vaccines are needed to make more practical use of DNA vaccines in olive flounder farms. Highlights • The potential of miR-155 as a molecular adjuvant for VHSV DNA vaccine was assessed. • Adjuvant effect of miR-155 was not discernible due to too low mortalities in immunized groups. • Significantly higher serum virucidal activity against HIRRV was induced by pFC-vG-miR155. • Immunization with 1 μg plasmids/fish was enough to induce effective adaptive immune responses. [ABSTRACT FROM AUTHOR]