In 10-minute speaking, N95 respirators significantly decreased SARS-CoV-2 emissions compared with no-mask wearing. However, SARS-CoV-2 was detected in the air even when wearing N95 and surgical masks in patients with high viral loads. Therefore, universal masking of infected and uninfected persons is important for preventing COVID-19 transmission via the air.

Female crabs enter a stage of rapid ovarian development after mating, and cholesterol is a substrate for steroid hormone synthesis. Therefore, in this experiment, an 8-week feeding trial was conducted to investigate the effects of mating treatments (mated crab and unmated crab) and three dietary cholesterol levels (0·09 %, 0·79 % and 1·40 %) on ovarian development, cholesterol metabolism and steroid hormones metabolism of adult female swimming crab (Portunus trituberculatus). The results indicated that crabs fed the diet with 0·79 % cholesterol significantly increased gonadosomatic index (GSI) and vitellogenin (VTG) content than other treatments in the same mating status. Moreover, mated crabs had markedly increased GSI and VTG content in the ovary and hepatopancreas than unmated crabs. The histological observation found that exogenous vitellogenic oocytes appeared in the mated crabs, while previtellogenic oocytes and endogenous vitellogenic oocytes were the primary oocytes in unmated crabs. The transmission electron microscopy analysis showed that when fed diet with 0·79 % cholesterol, the unmated crabs contained more rough endoplasmic reticulum and mated crabs had higher yolk content than other treatments. Furthermore, mating treatment and dietary 0·79 % cholesterol level both promoted cholesterol deposition by up-regulation of the mRNA and protein expression levels of class B scavenger receptors 1 (Srb1), while stimulating the secretion of steroid hormones by up-regulation of the mRNA and protein expression of steroidogenic acute regulatory protein (Star). Overall, the present results indicated that mating behaviour plays a leading role in promoting ovarian development, and dietary 0·79 % cholesterol level can further promote ovarian development after mating.

Background: Data on antimicrobial use at the national level is crucial to establish domestic antimicrobial stewardship policies and enable medical institutions to benchmark against each other. This study aimed to analyze antimicrobial use in Korean hospitals. Methods: We investigated the antimicrobials prescribed in Korean hospitals between 2018 and 2021, using data from the Health Insurance Review and Assessment. Primary care hospitals (PCHs), secondary care hospitals (SCHs), and tertiary care hospitals (TCHs) were included in this analysis. Antimicrobials were categorized according to the Korea National Antimicrobial Use Analysis System (KONAS) classification, which is suitable for measuring antimicrobial use in Korean hospitals. Results: Out of more than 1,900 hospitals, PCHs and TCHs represented the largest and lowest percentage of hospitals, respectively. The most frequently prescribed antimicrobial in 2021 was piperacillin/β-lactamase inhibitor (9.3%) in TCHs, ceftriaxone (11.0%) in SCHs, and cefazedone (18.9%) in PCHs. Between 2018 and 2021, the most used antimicrobial class according to the KONAS classification was ‘broad-spectrum antibacterial agents predominantly used for community-acquired infections’ in TCHs and SCHs, and 'narrow spectrum beta-lactam agents' in PCH. Total consumption of antimicrobials has decreased from 951.7 to 929.9 days of therapy (DOT)/1,000 patient-days in TCHs and from 817.8 to 752.2 DOT/1,000 patient-days in SCHs during study period, but not in PCHs (from 504.3 to 527.2 DOT/1,000 patient-days). Moreover, in 2021, while use of reserve antimicrobials has decreased from 13.6 to 10.7 DOT/1,000 patient-days in TCHs and from 4.6 to 3.3 DOT/1,000 patient-days in SCHs, it has increased from 0.7 to 0.8 DOT/1,000 patient-days in PCHs. Conclusion: This study confirms that antimicrobial use differs by hospital type in Korea. Recent increases of use of antimicrobials, including reserve antimicrobials, in PCHs reflect the challenges that must be addressed.

Background: Healthcare-associated central line associated bloodstream infection (HA-CLABSI) surveillance is important for monitoring healthcare-associated infections (HAIs) and evaluating effectiveness of infection prevention (IP) measures. However, implementing it is a laborious and time-consuming approach. Exclusive focus on central lines neglects HAI risk due to peripheral vascular catheters. This study aimed to assess whether HA-CLABSI incidence could be inferred from HA-bloodstream infection (BSI) trends and explore shift to HA-BSI surveillance. Methods: The study was performed in a Singaporean tertiary care hospital. Electronic medical records review was performed to determine whether positive blood cultures met Centers for Disease Control/National Health Safety Network (CDC/NHSN) definitions for HA-CLABSI and HA-BSI. Incident episodes of HA-BSI were included (excluding positive cultures repeated within 14 days). Incident organisms were explored to identify common causative pathogens (excluding same organisms isolated from cultures repeated within 14 days). CLABSI and BSI occurring ≥72hrs after admission were considered healthcare-associated. Patients under oncology or hematology service were considered immunocompromised. Incidence rates (IR) per 10,000 patient-days, patient characteristics and causative pathogens were compared between both indicators. Results: From January 2022 to October 2023, mean IR for HA-CLABSI was 0.63 (n=68) and for HA-BSI was 10.06 (n=1094). Median age of patients with HA-CLABSI was 66 years and HA-BSI was 68 years. HA-CLABSI and HA-BSI were more common in males (60.86% & 58.68%). Median duration between admission to HA-CLABSI was 20 days and to HA-BSI was 12 days. Median duration between central line insertion to HA-CLABSI was 16 days. Of 1094, 631 (57.7%) patients had vascular catheter(s) (i.e., IV cannula, port-a-cath, peripherally-inserted central catheter or central line) inserted at time of HA-BSI diagnosis, of whom 46 (7.3%) patients had CLABSI ±2days from positive blood culture. There was no significant correlation between monthly aggregate data from these indicators (Spearman’s correlation coefficient= 0.36, p-value=0.1). Predominant organisms causing HA-CLABSI and HA-BSI were gram negative bacteria (GNB, 40% & 57.21%), gram positive bacteria (24.71% & 22.23%), and fungi. Common GNB in CLABSI patients were Pseudomonas spp. and Stenotrophomonas maltophilia (8.24%), followed by Serratia marcescens and Klebsiella pneumoniae (5.88%). The frequent GNB in HA-BSI patients were Escherichia coli (15.4%), Klebsiella pneumonia (12.68%), and Pseudomonas spp. (6.69%). Common multi-drug resistant organisms were vancomycin-resistant Enterococcus faecium (10.59% & 3.69%) and methicillin-resistant Staphylococcus aureus (10.59% & 3.07%). Conclusion: HA-BSI did not correlate with HA-CLABSI. HA-BSI reflects heterogenous population outcomes. For utilization as surveillance indicator, further assessment on exclusion criteria is required to improve specificity.

Climate change poses a major threat to marine ecosystems, with its effects felt worldwide. A major effect of climate change on marine ecosystems is the rise in water temperature, leading to a northward expansion of habitats for marine organisms. Herdmania momus, a species of ascidians (sea squirts), originally found in tropical and subtropical regions, was introduced to the Korean Peninsula. In this study, we examined the habitat of H. momus along the southeastern coast of the Korean Peninsula between 2016 and 2022. We found that H. momus settlements were observed across the entire survey area, with confirmed habitation in Busan in 2016, Ulsan in 2021, and Gyeongju (the northernmost location) in 2022. The observed habitation trend indicates a rapid geographical expansion, occurring approximately 79 years earlier than previously predicted. These observations demonstrate that marine organisms are undergoing a more rapid geographical expansion than previously projected. These unexpected findings should inform government policies related to proactive measures and strategies for managing the impact of climate change on marine ecosystems.

The immobilization of antimicrobial drugs can be used to expand the application of antibacterial properties to consumer products. The purpose of this study was to stabilize an antimicrobial agent, levofloxacin (LVX), for sustained antibacterial activity by immobilizing the drug molecules in a layered double hydroxide (LDH) and embedded in a polyurethane substrate. As-prepared MgAl-LDH was calcined at 400°C and reconstructed with LVX for intercalation. The X-ray diffraction patterns and cross-sectional transmission electron microscopy images showed lattice expansion along the crystallographic c axis upon LVX intercalation, suggesting successful loading of the drug. Fourier-transform infrared spectra revealed that the structure of LVX was well preserved between LDH layers. Elemental analysis indicated that the loading capacity of LVX in the hybrid was 41.7%. Bacterial-colony forming inhibitory assay on Bacillus subtilis exhibited ~100% antibacterial activity of both LVX alone and LVX-LDH hybrid (LL). To determine sustainability of antibacterial activity by the hybrid, either LVX alone or LL hybrid was loaded in the polyurethane (PU) substrate for which antibacterial activity was evaluated before and after immersion in a phosphate-buffered saline for 3 days. The LVX-composited PU showed a dramatic decrease in antibacterial activity, down to 0% after buffer treatment; LL-composited PU still contained antibacterial activity (~34% of colony suppression) after phosphate-buffered saline immersion.

The development of nanoparticles incorporating Gd3+ has attracted interest in the field of contrasting nanomedicine for magnetic resonance (MR) and computed tomography (CT). In order to achieve an effective contrasting performance, the amount and stability of Gd incorporated as well as particle-size control of the nanoparticles should be considered simultaneously. In the current study, Gd-diethylenetriaminepentaacetate(Gd-DTPA) was incorporated into layered double hydroxide (LDH) to meet the physicochemical properties required for MR-CT dual contrasting nanomedicine. Strategically, the particle size and nanometer incorporation of Gd-DTPA into LDH (GL-R hybrid) were controlled homogeneously using the reverse micelle method. X-ray diffraction showed that the hybrid obtained possessed a hydrotalcite phase. Dynamic light scattering and electron microscopic analyses showed that the hybrid had a controlled size of <200 nm with significant homogeneity. Fast Fourier-transform of transmission electron microscopy confirmed that the platelets of the GL-R hybrids were oriented randomly to form inter-particle space, enabling the Gd-DTPA moiety to be encapsulated stably. The encapsulation efficiency of Gd-DTPA was 20.8%, which was sufficiently high compared with other Gd-DTPA-incorporatedLDH. According to X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy, Gd-DTPA incorporated in the hybrid preserved its structure intact. Its potential as a dual modal contrast agent was demonstrated by measuring the concentration-dependent Hounsfield unit and magnetic resonance relaxivity, which were determined to be 230 at 2 mg/mL and 5.8 in the range ~0.2–1 mM-Gd, respectively.

HIV-1 molecular surveillance provides a new approach to explore transmission risks and targeted interventions. From January to June 2021, 663 newly reported HIV-1 cases were recruited in Zhaotong City, Yunnan Province, China. The distribution characteristics of HIV-1 subtypes and HIV-1 molecular network were analysed. Of 542 successfully subtyped samples, 12 HIV-1 strains were identified. The main strains were CRF08_BC (47.0%, 255/542), CRF01_AE (17.0%, 92/542), CRF07_BC (17.0%, 92/542), URFs (8.7%, 47/542), and CRF85_BC (6.5%, 35/542). CRF08_BC was commonly detected among Zhaotong natives, illiterates, and non-farmers and was mostly detected in Zhaoyang County. CRF01_AE was frequently detected among married and homosexual individuals and mostly detected in Weixin and Zhenxiong counties. Among the 516 pol sequences, 187 (36.2%) were clustered. Zhaotong natives, individuals aged ≥60 years, and illiterate individuals were more likely to be found in the network. Assortativity analysis showed that individuals were more likely to be genetically associated when stratified by age, education level, occupation, and reporting area. The genetic diversity of HIV-1 reflects the complexity of local HIV epidemics. Molecular network analyses revealed the subpopulations to focus on and the characteristics of the risk networks. The results will help optimise local prevention and control strategies.

Although ethanol treatment is widely used to activate oocytes, the underlying mechanisms are largely unclear. Roles of intracellular calcium stores and extracellular calcium in ethanol-induced activation (EIA) of oocytes remain to be verified, and whether calcium-sensing receptor (CaSR) is involved in EIA is unknown. This study showed that calcium-free ageing (CFA) in vitro significantly decreased intracellular stored calcium (sCa) and CaSR expression, and impaired EIA, spindle/chromosome morphology and developmental potential of mouse oocytes. Although EIA in oocytes with full sCa after ageing with calcium does not require calcium influx, calcium influx is essential for EIA of oocytes with reduced sCa after CFA. Furthermore, the extremely low EIA rate in oocytes with CFA-downregulated CaSR expression and the fact that inhibiting CaSR significantly decreased the EIA of oocytes with a full complement of CaSR suggest that CaSR played a significant role in the EIA of ageing oocytes. In conclusion, CFA impaired EIA and the developmental potential of mouse oocytes by decreasing sCa and downregulating CaSR expression. Because mouse oocytes routinely treated for activation (18 h post hCG) are equipped with a full sCa complement and CaSR, the present results suggest that, while calcium influx is not essential, CaSR is required for the EIA of oocytes.

Objectives: Influenza vaccination is encouraged for all healthcare workers (HCWs) to reduce the risk of acquiring the infection and onward transmission to colleagues and patients during the influenza season. Thus, vaccination was introduced at Singapore General Hospital (SGH) in 2007 and has been offered to all HCWs at no cost. The HCW influenza vaccination program is conducted annually in October and biannually during years with vaccine mismatch. However, influenza vaccine uptake remained low among HCWs. We sought to determine the impact of the coronavirus disease 2019 (COVID-19) pandemic on influenza vaccine uptake among HCWs. Methods: At SGH, 2 methods of vaccine delivery are offered: centralized (1-month drop-in system during office hours) and decentralized (administered by vaccination teams in offices or ward staff in inpatient locations). In the 4-year study period between 2018 and 2021, 6 influenza vaccination exercise campaigns were conducted during 8 influenza seasons. During each exercise, ~9,000 HCWs were eligible for vaccination. Results: Prior to the COVID-19 pandemic, vaccine uptake in the Southern Hemisphere was 77.6% (6,964 of 8,977) in 2018 and 84.2% (7,296 of 8,670) in 2019. During the COVID-19 pandemic in 2020, vaccine uptake in the Southern Hemisphere increased by 10% to 94.1% (8,361 of 8,889). In the Northern Hemisphere, vaccine uptake was 79.2% (7,114 of 8,977) in 2018, and this increased by 17.9% to 97.1% (8,926 of 9,194) during the COVID-19 pandemic in 2020. During the 2021 Southern Hemisphere influenza season, no vaccination program was conducted because the risk of influenza was considered low due to the closure of international borders and the implementation of public health measures. In addition, priority was given to COVID-19 vaccination efforts. Conclusions: Increased uptake of the influenza vaccination was observed during the COVID-19 pandemic. Anxiety created by the respiratory disease pandemic and debate surrounding vaccines likely contributed to increased awareness and uptake in influenza vaccine among HCWs.

Objectives: Following a cluster of COVID-19 cases in a Singapore public hospital in April 2021, the local health authority mandated the use of N95 respirators in all inpatient wards. This increased the demand for N95 mask fit-testing to ensure that healthcare workers were donning respirators that fit their facial characteristics and hence provided protection through a good facial seal. The demand for fit-testing during the pandemic highlighted the scarcity of manpower and ergonomics concern, such as carpel tunnel syndrome experienced in long hours of qualitative fit-testing sessions. We evaluated the operational efficiency, cost-effectiveness, and difference in passing rate after the introduction of the quantitative method. Methods: Conventional qualitative fit-testing was conducted using manual pumping of a challenge agent, enabling the user to determine the fit of the respirator. The quantitative fit-testing protocol used a condensation particle counter (CPC) to measure the concentration of particles inside the mask and the atmosphere to determine the fit of respirator. The Occupational Safety and Health Administration (OSHA)–approved minimum fit factor of 100 was used as the criterion for a successful N95 respirator fit. Tubes used during quantitative fit-testing were reprocessed using thermal disinfection. Results: Quantitative mask fit-testing provided an objective numerical measure to assess adequate fit of N95 respirator, which provided users with confidence in the respirator fit. It addressed a manpower limitation issue because it did not require qualified trainers to conduct the test, and automation also prevented any potential occupational hazard from repeated actions required in qualitative fit-testing. An increase in the passing rate for N95 fit-testing from 94.5% to 95.5% was observed. However, the high cost of equipment, annual recalibration, and consumables must be considered. Conclusions: Quantitative N95 fit-testing, when adopted with careful consideration of its cost, is an approach to consider for hospital-wide fit-testing.

The unprecedented growth of Spanish-English dual language learners (DLLs) in new destination states (e.g., Georgia, Indiana, South Carolina, Tennessee) calls for better understanding of the relation between their bilingual vocabulary skills and English reading achievement. The current study focused on school-age Spanish-English DLLs (N = 60) in Tennessee and explored how various vocabulary knowledge conceptualizations predict English reading comprehension achievement, controlling for English word reading skills and grade level. Vocabulary knowledge was assessed using monolingual (English-only and Spanish-only) and bilingual (conceptual and total) scoring methods. Results showed that, while DLLs performed below the national mean for English-only and Spanish-only vocabulary, they performed within the average to above-average range for bilingually scored conceptual vocabulary. More uniquely, the expressive vocabulary knowledge emerged as a robust predictor of English reading comprehension above and beyond the influence of English word reading skills. Findings suggest practical and theoretical value of bilingually driven vocabulary assessment approaches. As expected, bilingually scored vocabulary provided a more comprehensive understanding of DLLs’ vocabulary knowledge by accounting for vocabulary knowledge in both Spanish and English, compared to monolingually scored vocabulary. We discuss theoretical and instructional implications, with a focus on asset-driven and scientific assessment understandings for supporting DLLs’ vocabulary and reading achievement in new destination states.