Downregulation of TASK-3 Channel Induces Senescence in Granulosa Cells of Bovine Cystic Ovarian Follicles.

Ovarian cysts are linked to hormone imbalances and altered gene expressions, but the connection between cysts and ion channel expression is understudied. This study explored the role of TWIK-related acid-sensitive K+ (TASK) channels in bovine ovarian cyst formation. The ovarian follicles were split into small (5 to 10 mm in diameter) and large (>25 mm in diameter) groups. Among the measured K+, Na+, and Cl- concentrations in follicular fluid (FF) obtained from small-sized follicles (SFs) and large-sized follicles (LFs), the K+ concentration was significantly lower in LFFF. Quantitative PCR, Western blot, and immunocytochemistry data revealed that TASK-3 expression levels significantly decreased by approximately 50% in LFs and granulosa cells obtained from LFs (LFGCs) compared to the corresponding controls. The TASK-3 protein was localized to the plasma membranes of GCs. The diameters of LFGCs were larger than those of SFGCs. The cell swelling response to exposure to a hypotonic solution (200 mOsm/L) was highly reduced in TASK-3-overexpressing cells compared to vector-transfected cells. TASK-3-knockdown cells showed arrested growth. Senescence markers were detected in LFGCs and TASK-3-knockdown cells. These findings suggest that reduced TASK-3 expression in LFs is associated with the inhibition of GC growth, leading to senescence and cyst formation.

Pathogenicity of Highly Pathogenic Avian Influenza A(H5N1) Viruses Isolated from Cats in Mice and Ferrets, South Korea, 2023.

The prevalence of highly pathogenic avian influenza (HPAI) A(H5N1) viruses has increased in wild birds and poultry worldwide, and concomitant outbreaks in mammals have occurred. During 2023, outbreaks of HPAI H5N1 virus infections were reported in cats in South Korea. The H5N1 clade 2.3.4.4b viruses isolated from 2 cats harbored mutations in the polymerase basic protein 2 gene encoding single amino acid substitutions E627K or D701N, which are associated with virus adaptation in mammals. Hence, we analyzed the pathogenicity and transmission of the cat-derived H5N1 viruses in other mammals. Both isolates caused fatal infections in mice and ferrets. We observed contact infections between ferrets, confirming the viruses had high pathogenicity and transmission in mammals. Most HPAI H5N1 virus infections in humans have occurred through direct contact with poultry or a contaminated environment. Therefore, One Health surveillance of mammals, wild birds, and poultry is needed to prevent potential zoonotic threats.

Dynamics of SARS-CoV-2 variants during the XBB wave in the Republic of Korea.

As COVID-19 has become endemic, SARS-CoV-2 variants are becoming increasingly diverse, underscoring the escalating importance of global genomic surveillance. This study analyzed 86,762 COVID-19 samples identified in the Republic of Korea from September 2022 to November 2023. The results revealed a consistent increase in the prevalence of the XBB variants following the dominance of BN.1, with various XBB sub-lineages co-circulating in the Republic of Korea. The overall nucleotide diversity (π) among the SARS-CoV-2 genomes was 0.00155. Evolutionary analysis revealed that the average time interval between the first detection and estimated date of the most recent common ancestor of Korean XBB sub-lineages was 47 d, suggesting that the novel variants were efficiently identified in the Korean surveillance system. The mutation rate was determined to be in the range of 5.6 × 10-4 to 9.1 × 10-4 substitutions/site/year. In conclusion, this study provides insights into the genetic diversity and evolutionary interpretation of the XBB sub-lineages during the XBB wave in the Republic of Korea, highlighting the importance of continued genomic surveillance for emerging variants.

The Effectiveness of Herbal Medicine on Feeding Intolerance in Preterm Infants: A Systematic Review and Meta-Analysis.

Background: Feeding intolerance (FI) refers to frequent feeding disruptions, that can adversely affect the growth, nutritional status, and long-term neurodevelopmental outcomes of preterm infants (born at 37 ≤ weeks of gestation). This review evaluated the efficacy of herbal medicine (HM) for FI compared to conventional treatments. Methods: An extensive search across 11 databases was conducted, including English, Chinese, and Korean databases, from August 1 to December 7, 2023. Our inclusion criteria were randomized clinical trials (RCTs) that compared the efficacy of HM with conventional treatments against conventional treatments alone. Statistical analyses involved calculating the mean difference (MD), standardized mean difference (SMD), and risk ratio (RR) with a 95% confidence interval (CI), and assessing the bias risk (RoB 2) using Review Manager Version 5.4 software. The quality of evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) rating system. Results: The meta-analysis showed that combined HM treatments exhibited superior outcomes compared to conventional treatments alone. The time to achieve full enteral feeding (n = 638, random effects MD: -2.91, 95% CI: -4.13 to -1.69), duration of FI (n = 366, fixed effects MD: -1.58, 95% CI: -2.01 to -1.16), and total effective rate (n = 774, random effects RR: 1.26, 95% CI: 1.11 to 1.42) improved with HM. Mild adverse events, such as diarrhea and increased defecation frequency, occurred in 4.17% of the HM combined group, compared to 1.42% in the conventional treatment group. Conclusions: The findings suggest that combining HM with conventional treatments could be more effective for FI, suggesting HM as an early intervention for FI in preterm infants. Further research on the efficacy and safety of HM in preterm infants is necessary.

Clinical outcome of ampicillin or ampicillin/sulbactam versus glycopeptides in ampicillin-susceptible Enterococcus faecalis/faecium bacteremia: a 10-year retrospective cohort study.

BACKGROUND: Glycopeptides for ampicillin-susceptible Enterococcus faecalis/faecium bacteremia are readily prescribed depending on the severity of the condition. However, there is limited data on the outcomes of glycopeptide use compared to ampicillin-containing regimens for ampicillin-susceptible E. faecalis/faecium bacteremia. From an antibiotic stewardship perspective, it is important to determine whether the use of glycopeptides is associated with improved clinical outcomes in patients with ampicillin-susceptible E. faecalis/faecium bacteremia. METHODS: This retrospective cohort study was conducted at a university-affiliated hospital between January 2010 and September 2019. We collected data from patients with positive blood cultures for Enterococcus species isolates. The clinical data of patients who received ampicillin-containing regimens or glycopeptides as definitive therapy for ampicillin-susceptible E. faecalis/faecium bacteremia were reviewed. Multivariate logistic regression analysis was performed to identify risk factors for 28-day mortality. RESULTS: Ampicillin-susceptible E. faecalis/faecium accounted for 41.2% (557/1,353) of enterococcal bacteremia cases during the study period. A total of 127 patients who received ampicillin-containing regimens (N = 56) or glycopeptides (N = 71) as definitive therapy were included in the analysis. The 28-day mortality rate was higher in patients treated with glycopeptides (19.7%) than in those treated with ampicillin-containing regimens (3.6%) (p = 0.006). However, in the multivariate model, antibiotic choice was not an independent predictor of 28-day mortality (adjusted OR, 3.7; 95% CI, 0.6-23.6). CONCLUSIONS: Glycopeptide use was not associated with improved mortality in patients with ampicillin-susceptible E. faecalis/faecium bacteremia. This study provides insights to reduce the inappropriate use of glycopeptides in ampicillin-susceptible E. faecalis/faecium bacteremia treatment and promote antimicrobial stewardship.

Novel Flowable Hemostatic Agent ActiClot: Efficacy and Safety Assessment in Rat and Porcine Models.

Background/Objectives: This study evaluated the hemostatic performance and safety of ActiClot (ATC), a new flowable hemostatic agent, through in vivo tests. Methods: ATC was compared with the commercially available FLOSEAL®. ATC consists of carboxymethyl starch, thrombin, and sorbitol powders in Syringe I, and a calcium chloride solution in Syringe II. In vivo evaluation used rat liver bleeding and porcine heart bleeding models. Safety was assessed using a rat subcutaneous implantation model. Results: ATC significantly reduced hemostasis time (70.00 ± 7.35 s) compared to gauze control (240.63 ± 32.31 s) in the rat liver model, showing a 70% reduction. There was no significant difference between ATC and FLOSEAL® (58.75 ± 13.42 s). In the porcine heart model, both agents achieved 100% hemostasis within 3 min, with no significant difference in success rates within 2 min (ATC 87.5%, FLOSEAL® 75%). The gauze control group failed in all tests. The rat subcutaneous implantation model showed no visual ATC observation after 48 h, indicating biocompatibility, with no inflammation observed. Conclusions: ATC demonstrated effective hemostatic performance similar to FLOSEAL® in two in vivo models, with faster hemostasis in the rat liver model. It also showed excellent safety and biocompatibility, indicating its potential for surgical and emergency bleeding control.

Variations in the Antivirulence Effects of Fatty Acids and Virstatin against Vibrio cholerae Strains.

The expression of two major virulence factors of Vibrio cholerae, cholera toxin (CT) and toxin co-regulated pilus (TCP), is induced by environmental stimuli through a cascade of interactions among regulatory proteins known as the ToxR regulon when the bacteria reach the human small intestine. ToxT is produced via the ToxR regulon and acts as the direct transcriptional activator of CT (ctxAB), TCP (tcp gene cluster), and other virulence genes. Unsaturated fatty acids (UFAs) and several small-molecule inhibitors of ToxT have been developed as antivirulence agents against V. cholerae. This study reports the inhibitory effects of fatty acids and virstatin (a small-molecule inhibitor of ToxT) on the transcriptional activation functions of ToxT in isogenic derivatives of V. cholerae strains containing various toxT alleles. The fatty acids and virstatin had discrete effects depending on the ToxT allele (different by 2 amino acids), V. cholerae strain, and culture conditions, indicating that V. cholerae strains could overcome the effects of UFAs and small-molecule inhibitors by acquiring point mutations in toxT. Our results suggest that small-molecule inhibitors should be examined thoroughly against various V. cholerae strains and toxT alleles during development.

Factors influencing nurses' compliance related to the use of personal protective equipment during the COVID-19 pandemic: A descriptive cross-sectional study.

AIM: To determine how nurses' experiences with the coronavirus disease (COVID-19) pandemic affected their knowledge, awareness, and compliance related to the use of personal protective equipment (PPE) during the COVID-19 pandemic in South Korea. DESIGN: A descriptive cross-sectional study. METHODS: A total of 247 nurses in South Korea participated in this study between May 10 and 19, 2023. An online self-report questionnaire was used to collect data on demographic and occupational characteristics, COVID-19 experience, knowledge, awareness, and compliance related to the use of PPE. Factors affecting compliance were analysed using hierarchical multiple linear regression. RESULTS: Mean age of the nurses was 31.92, and 94.3% were women. Most had a bachelor's degree or higher and the mean clinical experience as a nurse was 6.45 years. Knowledge of the use of PPE was 8.45 out of 10, awareness was 3.52 out of 5, and compliance was 4.28 out of 5. Knowledge and awareness were correlated with compliance related to PPE use. Awareness (ß = 0.234, p < 0.001), knowledge (ß = 0.218, p < 0.001), experience caring for COVID-19 patients (ß = 0.234, p = 0.004), optional fourth dose vaccine (ß = 0.150, p = 0.017), clinical experience (ß = 0.140, p = 0.022), and COVID-19 infection control education (ß = 0.115, p = 0.037) were found to have a significant impact on compliance. CONCLUSION: During the COVID-19 pandemic, nurses' knowledge and awareness of PPE use was a crucial factor in compliance. factors such as clinical experience, experience in caring for COVID-19 patients, optional vaccination, and completion of COVID-19 education also influenced compliance. We hope that these factors can provide a basis for developing training programs for nurses to respond to future emerging infectious diseases.

Replication kinetics and infectivity of SARS-CoV-2 Omicron variant sublineages recovered in the Republic of Korea.

BACKGROUND: We analyzed the correlation between the infectivity and transmissibility of the severe acute respiratory syndrome coronavirus 2 Omicron sublineages BA.1, BA. 2, BA.4, and BA.5. METHODS: We assessed viral replication kinetics and infectivity at the cellular level. Nasopharyngeal and oropharyngeal specimens were obtained from patients with coronavirus disease 2019, confirmed using whole-genome sequencing to be caused by the Omicron sublineages BA.1, BA.2, BA.4, or BA.5. These specimens were used to infect Vero E6 cells, derived from monkey kidneys, for the purpose of viral isolation. Viral stocks were then passaged in Vero E6 cells at a multiplicity of infection of 0.01, and culture supernatants were harvested at 12-hour intervals for 72 hours. To evaluate viral replication kinetics, we determined the cycle threshold values of the supernatants using real-time reverse transcription polymerase chain reaction and converted these values to genome copy numbers. RESULTS: The viral load was comparable between BA.2, BA.4, and BA.5, whereas BA.1 exhibited a lower value. The peak infectious load of BA.4 was approximately 3 times lower than that of BA.2 and BA.5, while the peak load of BA.2 and BA.5 was about 7 times higher than that of BA.1. Notably, BA.1 demonstrated the lowest infectivity over the entire study period. CONCLUSION: Our results suggest that the global BA.5 wave may have been amplified by the higher viral replication and infectivity of BA.5 compared to other Omicron sublineages. These analyses could support the rapid assessment of the impact of novel variants on case incidence.

Broncho-Vaxom Attenuates Lipopolysaccharide-Induced Inflammation in a Mouse Model of Acute Lung Injury.

Acute lung injury (ALI) is a condition associated with acute respiratory failure, resulting in significant morbidity and mortality. It involves cellular changes such as disruption of the alveolar-capillary membrane, excessive neutrophil migration, and release of inflammatory mediators. Broncho-Vaxom® (BV), a lyophilized product containing cell membrane components derived from eight bacteria commonly found in the respiratory tract, is known for its potential to reduce viral and bacterial lung infections. However, the specific effect of BV on ALI has not been clearly defined. This study explored the preventive effects of BV and its underlying mechanisms in a lipopolysaccharide (LPS)-induced ALI mouse model. Oral BV (1 mg/kg) gavage was administered one hour before the intratracheal injection of LPS to evaluate its preventive effect on the ALI model. The pre-administration of BV significantly mitigates inflammatory parameters, including the production of inflammatory mediators, macrophage infiltration, and NF-κB activation in lung tissue, and the increase in inflammatory cells in bronchoalveolar lavage fluid (BALF). Moreover, BV (3 µg/mL) pretreatment reduced the expression of M1 macrophage markers, interleukins (IL-1ß, IL-6), tumor necrosis factor α, and cyclooxygenase-2, which are activated by LPS, in both mouse alveolar macrophage MH-S cells and human macrophage THP-1 cells. These findings showed that BV exhibits anti-inflammatory effects by suppressing inflammatory mediators through the NF-κB pathway, suggesting its potential to attenuate bronchial and pulmonary inflammation.