Fitness costs of Tn1546-type transposons harboring the vanA operon by plasmid type and structural diversity in Enterococcus faecium.

BACKGROUND: This study analyzed the genetic traits and fitness costs of vancomycin-resistant Enterococcus faecium (VREfm) blood isolates carrying Tn1546-type transposons harboring the vanA operon. METHODS: All E. faecium blood isolates were collected from eight general hospitals in South Korea during one-year study period. Antimicrobial susceptibility testing and vanA and vanB PCR were performed. Growth rates of E. faecium isolates were determined. The vanA-positive isolates were subjected to whole genome sequencing and conjugation experiments. RESULTS: Among 308 E. faecium isolates, 132 (42.9%) were positive for vanA. All Tn1546-type transposons harboring the vanA operon located on the plasmids, but on the chromosome in seven isolates. The plasmids harboring the vanA operon were grouped into four types; two types of circular, nonconjugative plasmids (Type A, n = 50; Type B, n = 46), and two types of putative linear, conjugative plasmids (Type C, n = 16; Type D, n = 5). Growth rates of vanA-positive E. faecium isolates were significantly lower than those of vanA-negative isolates (P < 0.001), and reduction in growth rate under vancomycin pressure was significantly larger in isolates harboring putative linear plasmids than in those harboring circular plasmids (P = 0.020). CONCLUSIONS: The possession of vanA operon was costly to bacterial hosts in antimicrobial-free environment, which provide evidence for the importance of reducing vancomycin pressure for prevention of VREfm dissemination. Fitness burden to bacterial hosts was varied by type and size of the vanA operon-harboring plasmid.

CcpA and CodY Regulate CRISPR-Cas System of Streptococcus mutans.

Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated (Cas) genes are widely recognized as bacterial adaptive immune systems against invading viruses and bacteriophages. The oral pathogen Streptococcus mutans encodes two CRISPR-Cas loci (CRISPR1-Cas and CRISPR2-Cas), and their expression under environmental conditions is still under investigation. In this study, we investigated the transcriptional regulation of cas operons by CcpA and CodY, two global regulators that contribute to carbohydrate and (p)ppGpp metabolism. The possible promoter regions for cas operons and the binding sites for CcpA and CodY in the promoter regions of both CRISPR-Cas loci were predicted using computational algorithms. We found that CcpA could directly bind to the upstream region of both cas operons, and detected an allosteric interaction of CodY within the same region. The binding sequences of the two regulators were identified through footprinting analysis. Our results showed that the promoter activity of CRISPR1-Cas was enhanced under fructose-rich conditions, while deletion of the ccpA gene led to reduced activity of the CRISPR2-Cas promoter under the same conditions. Additionally, deletion of the CRISPR systems resulted in a significant decrease in fructose uptake ability compared to the parental strain. Interestingly, the accumulation of guanosine tetraphosphate (ppGpp) was reduced in the presence of mupirocin, which induces a stringent response, in the CRISPR1-Cas-deleted (ΔCR1cas) and both CRISPR-Cas-deleted (ΔCRDcas) mutant strains. Furthermore, the promoter activity of both CRISPRs was enhanced in response to oxidative or membrane stress, while the CRISPR1 promoter activity was reduced under low-pH conditions. Collectively, our findings demonstrate that the transcription of the CRISPR-Cas system is directly regulated by the binding of CcpA and CodY. These regulatory actions play a crucial role in modulating glycolytic processes and exerting effective CRISPR-mediated immunity in response to nutrient availability and environmental cues. IMPORTANCE An effective immune system has evolved not only in eukaryotic organisms but also in microorganisms, enabling them to rapidly detect and neutralize foreign invaders in the environment. Specifically, the CRISPR-Cas system in bacterial cells is established through a complex and sophisticated regulatory mechanism involving specific factors. In this study, we demonstrate that the expression of two CRISPR systems in S. mutans can be controlled by two global regulators, CcpA and CodY, which play critical roles in carbohydrate metabolism and amino acid biosynthesis. Importantly, our results show that the expression of the CRISPR-Cas system in S. mutans influences (p)ppGpp production during the stringent response, which is a gene expression regulatory response that aids in environmental stress adaptation. This transcriptional regulation by these regulators enables a CRISPR-mediated immune response in a host environment with limited availability of carbon sources or amino acids, while ensuring efficient carbon flux and energy expenditure to support multiple metabolic processes.

The Auxiliary Role of Virtual Reality in Enhancing the Effects of Disaster News on Empathy and Fear: The Mediating Role of Presence.

This study conducted a two-condition between-subjects laboratory experiment (N = 147) to examine the effects of textual disaster news combined with a 360° video in different modes (virtual reality [VR] vs. two dimensional screen) on cognitive/affective empathy and fear. Additionally, the mediating role of presence (social and spatial presence) was considered. Results indicated that the news article presented through an immersive VR mode directly led to greater levels of presence and cognitive empathy but not affective empathy and fear. The effects on social presence further resulted in greater cognitive and affective empathy, not fear. Meanwhile, spatial presence enhanced by VR led to greater levels of emotions (affective empathy and fear) but not cognitive empathy. These findings suggest the dynamic mechanisms of how an immersive VR modality can function as a complementary tool for traditional news to improve audience engagement, which centers on emotion-related outcomes in tandem with cognitive responses.

Deep-learning model for screening sepsis using electrocardiography.

BACKGROUND: Sepsis is a life-threatening organ dysfunction and a major healthcare burden worldwide. Although sepsis is a medical emergency that requires immediate management, screening for the occurrence of sepsis is difficult. Herein, we propose a deep learning-based model (DLM) for screening sepsis using electrocardiography (ECG). METHODS: This retrospective cohort study included 46,017 patients who were admitted to two hospitals. A total of 1,548 and 639 patients had sepsis and septic shock, respectively. The DLM was developed using 73,727 ECGs from 18,142 patients, and internal validation was conducted using 7774 ECGs from 7,774 patients. Furthermore, we conducted an external validation with 20,101 ECGs from 20,101 patients from another hospital to verify the applicability of the DLM across centers. RESULTS: During the internal and external validations, the area under the receiver operating characteristic curve (AUC) of the DLM using 12-lead ECG was 0.901 (95% confidence interval, 0.882-0.920) and 0.863 (0.846-0.879), respectively, for screening sepsis and 0.906 (95% confidence interval (CI), 0.877-0.936) and 0.899 (95% CI, 0.872-0.925), respectively, for detecting septic shock. The AUC of the DLM for detecting sepsis using 6-lead and single-lead ECGs was 0.845-0.882. A sensitivity map revealed that the QRS complex and T waves were associated with sepsis. Subgroup analysis was conducted using ECGs from 4,609 patients who were admitted with an infectious disease, and the AUC of the DLM for predicting in-hospital mortality was 0.817 (0.793-0.840). There was a significant difference in the prediction score of DLM using ECG according to the presence of infection in the validation dataset (0.277 vs. 0.574, p < 0.001), including severe acute respiratory syndrome coronavirus 2 (0.260 vs. 0.725, p = 0.018). CONCLUSIONS: The DLM delivered reasonable performance for sepsis screening using 12-, 6-, and single-lead ECGs. The results suggest that sepsis can be screened using not only conventional ECG devices but also diverse life-type ECG machines employing the DLM, thereby preventing irreversible disease progression and mortality.

Phthalate Plasticizers in Children's Products and Estimation of Exposure: Importance of Migration Rate.

Plasticizers are added to diverse consumer products including children's products. Owing to their potential for endocrine disruption, the use of phthalate plasticizers is restricted in many children's products. In this study, exposure to five phthalate esters (dibutylphthalate, di(2-ethylhexyl) phthalate (DEHP), diethyl phthalate, di-isobutyl phthalate, and diisononyl phthalate (DINP)) and an alternative (di-ethylhexyl adipate) was assessed by the use of children's products based on chemical analysis of 3345 products purchased during 2017 and 2019 in Korea. Plasticizers were found above the detection limits in 387 products, and DEHP and DINP were the two most predominantly detected plasticizers. Deterministic and probabilistic estimation of the margin of exposure at a screening level revealed that the use of children's products might be an important risk factor. However, it is also highly likely that the exposure could be overestimated, because the migration rate was estimated based solely on the content of plasticizers in children's products. Chemical migration is a key process determining the absorption of plasticizers from products; thus, further refinements in experimental determination or model estimation of the migration rate are required.

Microplastics in Food: A Review on Analytical Methods and Challenges.

Human exposure to microplastics contained in food has become a significant concern owing to the increasing accumulation of microplastics in the environment. In this paper, we summarize the presence of microplastics in food and the analytical methods used for isolation and identification of microplastics. Although a large number of studies on seafood such as fish and shellfish exist, estimating the overall human exposure to microplastics via food consumption is difficult owing to the lack of studies on other food items. Analytical methods still need to be optimized for appropriate recovery of microplastics in various food matrices, rendering a quantitative comparison of different studies challenging. In addition, microplastics could be added or removed from ingredients during processing or cooking. Thus, research on processed food is crucial to estimate the contribution of food to overall human microplastic consumption and to mitigate this exposure in the future.

Artificial intelligence algorithm to predict the need for critical care in prehospital emergency medical services.

BACKGROUND: In emergency medical services (EMSs), accurately predicting the severity of a patient's medical condition is important for the early identification of those who are vulnerable and at high-risk. In this study, we developed and validated an artificial intelligence (AI) algorithm based on deep learning to predict the need for critical care during EMS. METHODS: We conducted a retrospective observation cohort study. The algorithm was established using development data from the Korean national emergency department information system, which were collected during visits in real time from 151 emergency departments (EDs). We validated the algorithm using EMS run sheets from two EDs. The study subjects comprised adult patients who visited EDs. The endpoint was critical care, and we used age, sex, chief complaint, symptom onset to arrival time, trauma, and initial vital signs as the predicted variables. RESULTS: The number of patients in the development data was 8,981,181, and the validation data comprised 2604 EMS run sheets from two hospitals. The area under the receiver operating characteristic curve of the algorithm to predict the critical care was 0.867 (95% confidence interval, [0.864-0.871]). This result outperformed the Emergency Severity Index (0.839 [0.831-0.846]), Korean Triage and Acuity System (0.824 [0.815-0.832]), National Early Warning Score (0.741 [0.734-0.748]), and Modified Early Warning Score (0.696 [0.691-0.699]). CONCLUSIONS: The AI algorithm accurately predicted the need for the critical care of patients using information during EMS and outperformed the conventional triage tools and early warning scores.

Evaluation of the BD Phoenix M50 Automated Microbiology System for Antimicrobial Susceptibility Testing with Clinical Isolates in Korea.

The objectives of this study were to evaluate the performance of the BD Phoenix™ M50 system with two antimicrobial susceptibility testing (AST) panels against clinical isolates in South Korea and the accuracy of determining carbapenem and colistin susceptibility compared with reference methods. A total of 825 nonduplicated clinical isolates were included in this study. Bacterial identification was performed using Bruker Biotyper and 16S rDNA sequencing. Antimicrobial susceptibilities were tested by disk diffusion, broth microdilution, and agar dilution methods. AST with the Phoenix system was performed following the manufacturer's instructions. The categorical agreement (CA), very major error (VME), major error (ME), and minor error (mE) rates were calculated for each antibiotic. CA rates between the results of the Phoenix system and reference methods were more than 90% for most antibiotics except for ciprofloxacin in enterococci (82.7%, 163/197) and cefepime in Acinetobacter species (88.9%, 88/99). VME and ME rates were less than 3% for all the antibiotics tested in this study. Minimum inhibitory concentration (MIC) values for carbapenem and colistin determined by the Phoenix system were highly correlated with those of dilution methods, exhibiting 99.2% (384/387), 96.7% (374/387), and 98.5% (129/131) of the agreement rate within onefold dilution difference for imipenem, meropenem, and colistin, respectively. The BD Phoenix M50™ system showed reliable performance for AST in clinical microbiology laboratories and for detecting carbapenem and colistin resistance in Gram-negative clinical isolates.

New Delhi Metallo-Beta-Lactamase-Producing Enterobacteriaceae in South Korea Between 2010 and 2015.

This study was carried out to investigate the epidemiological time-course of New Delhi metallo-beta-lactamase- (NDM-) mediated carbapenem resistance in Enterobacteriaceae in South Korea. A total of 146 non-duplicate NDM-producing Enterobacteriaceae recovered between 2010 and 2015 were voluntarily collected from 33 general hospitals and confirmed by PCR. The species were identified by sequences of the 16S rDNA. Antimicrobial susceptibility was determined either by the disk diffusion method or by broth microdilution, and the carbapenem MICs were determined by agar dilution. Then, multilocus sequence typing and PCR-based replicon typing was carried out. Co-carried genes for drug resistance were identified by PCR and sequencing. The entire genomes of eight random selected NDM producers were sequenced. A total of 69 Klebsiella pneumoniae of 12 sequence types (STs), 34 Escherichia coli of 15 STs, 28 Enterobacter spp. (including one Enterobacter aerogenes), nine Citrobacter freundii, four Raoultella spp., and two Klebsiella oxytoca isolates produced either NDM-1 (n = 126), NDM-5 (n = 18), or NDM-7 (n = 2). The isolates co-produced CTX-M-type ESBL (52.1%), AmpCs (27.4%), additional carbapenemases (7.1%), and/or 16S rRNA methyltransferases (4.8%), resulting in multidrug-resistance (47.9%) or extensively drug-resistance (52.1%). Among plasmids harboring blaNDM, IncX3 was predominant (77.4%), followed by the IncFII type (5.8%). Genome analysis revealed inter-species and inter-strain horizontal gene transfer of the plasmid. Both clonal dissemination and plasmid transfer contributed to the wide dissemination of NDM producers in South Korea.

Is There a Difference in Stability After Intraoral Vertical Ramus Osteotomy Between Vertically High-Angle and Normal-Angle Patients?

PURPOSE: Few studies have evaluated the relapse pattern of intraoral vertical ramus osteotomy (IVRO) for the correction of mandibular prognathism with a high angle. The aim of this study was to measure the association between vertical facial types (high and normal mandibular plane angle) and relapse after IVRO for the management of mandibular prognathism. MATERIALS AND METHODS: The retrospective cohort study sample (skeletal Class III patients) was divided into 2 groups according to the angle of the sella-nasion plane relative to the mandibular plane (SN-MP) at the initial examination. Lateral cephalograms were analyzed for the predictor (facial type) and outcome (cephalometric changes over time) variables before surgery, 7 days after surgery, and 12 months after surgery. The 2 groups were matched for sample size (n = 20 in each). Data were analyzed using repeated-measures analysis of variance with Bonferroni correction. RESULTS: The normal-angle group (group N, SN-MP from 27° to 37°) and high-angle group (group H, SN-MP >37°) were not significantly different in terms of gender and age at the initial examination. Seven days after surgery, the mandibles in group H moved 2.5 mm more superiorly than those in group N (P = .013); consequently, the amount of overbite correction in group H was approximately 2 mm greater than that in group N (P = .002). Nevertheless, 12 months after surgery, there was no statistically significant difference in relapse of the maxilla and mandible between the 2 groups. In the 2 groups, the mandible moved approximately 0.7 mm superiorly during retention. CONCLUSIONS: These findings suggest that IVRO is a clinically acceptable and stable treatment modality for mandibular prognathism with a high angle.

Three-Dimensional Polymeric Mechanical Metamaterials Fabricated by Multibeam Interference Lithography with the Assistance of Plasma Etching.

The pentamode structure is a type of mechanical metamaterial that displays dramatically different bulk and shear modulus responses. In this study, a face-centered cubic (FCC) polymeric microstructure was fabricated by using SU8 negative-type photoresists and multibeam interference exposure. Isotropic plasma etching is used to control the solid-volume fraction; for the first time, we obtained a structure with the minimum solid-volume fraction as low as 15% that still exhibited high structural integrity. Using this method, we reduced the width of atom-to-atom connections by up to 40 nm. We characterize the effect of the connection area on the anisotropy of the mechanical properties using simulations. Nanoindentation measurements were also conducted to evaluate the energy dissipation by varying the connection area. The Young's/shear modulus ratio is 5 times higher for the etched microstructure than that of the bulk SU8 materials. The use of interference lithography may enable the properties of microscale materials to be engineered for various applications, such as MEMS.

Controlled Unusual Stiffness of Mechanical Metamaterials.

Mechanical metamaterials that are engineered with sub-unit structures present unusual mechanical properties depending on the loading direction. Although they show promise, their practical utility has so far been somewhat limited because, to the best of our knowledge, no study about the potential of mechanical metamaterials made from sophisticatedly tailored sub-unit structures has been made. Here, we present a mechanical metamaterial whose mechanical properties can be systematically designed without changing its chemical composition or weight. We study the mechanical properties of triply periodic bicontinuous structures whose detailed sub-unit structure can be precisely fabricated using various sub-micron fabrication methods. Simulation results show that the effective wave velocity of the structures along with different directions can be designed to introduce the anisotropy of stiffness by changing a volume fraction and aspect ratio. The ratio of Young's modulus to shear modulus can be increased by up to at least 100, which is a 3500% increase over that of isotropic material (2.8, acrylonitrile butadiene styrene). Furthermore, Poisson's ratio of the constituent material changes the ratio while Young's modulus does not influence it. This study presents the promising potential of mechanical metamaterials for versatile industrial and biomedical applications.

Major factors contributing to anterior and posterior relapse after intraoral vertical ramus osteotomy.

The aim of this retrospective cohort study was to investigate the factors contributing to mandibular relapse after intraoral vertical ramus osteotomy (IVRO) while controlling for possible confounders. Forty-seven patients who underwent bimaxillary surgery were divided into three groups according to the direction of horizontal mandibular relapse: a stable group (group S), a posterior relapse group (group P), and an anterior relapse group (group A). Lateral cephalograms were analysed 1 month before and at 7 days and 12 months after surgery. One month before surgery, the pogonion in group A was positioned about 13 mm more anteriorly than in group P (P < 0.05). Immediately after surgery, the mandibles in groups A and S had moved about 6 mm more posteriorly than in group P. At 12 months, both the mandibles (point B) and the maxillae (point A) had moved posteriorly in group P (P < 0.05). A multivariate linear regression analysis showed that the amount of setback was the one key factor predicting postoperative mandibular changes 12 months after IVRO. As the amount of setback decreased, mandibular posterior horizontal relapse increased after IVRO. These findings suggest that the amount of setback can be a key factor predicting postoperative mandibular relapse.

Liquid immersion thermal crosslinking of 3D polymer nanopatterns for direct carbonisation with high structural integrity.

The direct pyrolytic carbonisation of polymer patterns has attracted interest for its use in obtaining carbon materials. In the case of carbonisation of nanopatterned polymers, the polymer flow and subsequent pattern change may occur in order to relieve their high surface energies. Here, we demonstrated that liquid immersion thermal crosslinking of polymer nanopatterns effectively enhanced the thermal resistance and maintained the structure integrity during the heat treatment. We employed the liquid immersion thermal crosslinking for 3D porous SU8 photoresist nanopatterns and successfully converted them to carbon nanopatterns while maintaining their porous features. The thermal crosslinking reaction and carbonisation of SU8 nanopatterns were characterised. The micro-crystallinity of the SU8-derived carbon nanopatterns was also characterised. The liquid immersion heat treatment can be extended to the carbonisation of various polymer or photoresist nanopatterns and also provide a facile way to control the surface energy of polymer nanopatterns for various purposes, for example, to block copolymer or surfactant self-assemblies.

3D Woven-Like Carbon Micropattern Decorated with Silicon Nanoparticles for Use in Lithium-Ion Batteries.

Carbon/silicon composite materials are a promising anode substrate for use in lithium-ion batteries. In this study, we suggest a new architecture for a composite electrode made of a woven-like carbon material decorated with silicon nanoparticles. The 3D woven-like carbon (WLC) structure was fabricated using direct carbonization of multi-beam interference lithography polymer patterns. Subsequent solution coating was applied to decorate the WLC with silicon nanoparticles (SiNPs). The SiNP/WLC electrode exhibited a specific capacity of 930 mAh g(-1) , which is three times higher than the specific capacity of the bare electrode. Specifically, the SiNP/WLC electrode exhibited an outstanding retention capacity of 81 % after 50 cycles and a Coulombic efficiency of more than 98 %. This rate capability performance was attributed to the WLC structure and the uniform decoration of the SiNPs.

Interdisciplinary treatment for an adult patient with anterior open bite, severe periodontitis, and intellectual disability.

This case report describes the beneficial effects of the interdisciplinary treatment of an adult patient with severe skeletal periodontal problems. A 30-year-old female patient presented with anterior open bite, gummy smile, and facial asymmetry. The patient had chronic generalized severe periodontitis with pathologic maxillary anterior teeth migration and mild intellectual disability. Treatment included 6 months of periodontal treatment, followed by presurgical orthodontic treatment, a Le Fort I osteotomy with anterior segmental osteotomy, a bilateral sagittal split ramus osteotomy, and postsurgical orthodontic treatment. After treatment completion, the patient exhibited functional and aesthetic improvements. Her periodontal condition improved and was maintained after the treatment. Here, we demonstrate a successful treatment outcome in a complicated case following a systematic interdisciplinary approach performed with the correct diagnosis and treatment planning.

Synthesis of antifungal evaluation of 2H-[1,2,3]Triazolo[4,5-g]isoquinoline-4,9-diones.

2H-[1,2,3]Triazolo[4,5-g]isoquinoline-4,9-diones and 2H-[1,2,3]triazolo[4,5-g]quinoline-4,9-diones were synthesized and tested for in vitro antifungal activity against pathogenic fungi. Many of those synthesized showed potent antifungal activity. Compounds 3a, 3b, 3g, and 3h completely inhibited the growth of all fungal species tested at the MIC level of 0.8-12.5 µg/mL. The results suggest that 2H-[1,2,3]triazolo[4,5-g]isoquinoline-4,9-diones could be antifungal agents.

Lithographically defined three-dimensional pore-patterned carbon with nitrogen doping for high-performance ultrathin supercapacitor applications.

Supercapacitors that exhibit long cycle lives and fast charge/discharge rates are a promising energy-storage technology for next-generation mobile or wearable electronic systems. A great challenge facing the fabrication of ultrathin supercapacitor components, specifically their porous electrodes, is whether such components can be integrated with the fabrication of electronic devices, i.e., semiconductor fabrication processes. Here, we introduce the lithographic fabrication of micrometre-thick, submicrometre-pore-patterned carbon for supercapacitor electrodes. The pore patterns designed by multi-beam interference lithography and direct carbonisation of the photoresist pattern produced pore-patterned carbon films. A facile doping process was subsequently employed to introduce nitrogen atoms into the carbon, which was intended to further enhance the carbon's capacitive properties. Specifically, during these fabrication steps, we developed an approach that uses a supporting shell on the surface of the pore patterns to maintain their structural integrity. The nitrogen-doped, pore-patterned carbon electrodes exhibited an areal specific capacitance of 32.7 mF/cm(2) at 0.5 mA/cm(2) when used as supercapacitor electrodes, which is approximately 20 times greater than that of commercially available MWCNT films measured under the same conditions.

Severe skeletal Class III malocclusion treated with 2-stage orthognathic surgery with a mandibular step osteotomy.

To reduce a large amount of mandibular setback and to prevent pharyngeal airway space narrowing when correcting a severe anteroposterior skeletal discrepancy, a mandibular step osteotomy is often combined with 2-stage orthognathic surgery. This case report describes a successful 2-stage orthognathic treatment combined with a mandibular step osteotomy. A 20-year-old man had severe mandibular protrusion, facial asymmetry, and macroglossia. Phase 1 surgery included the mandibular step osteotomy and a partial glossectomy; then we performed phase 2 surgery with a 2-piece LeFort I segmental osteotomy and a bilateral intraoral vertical ramus osteotomy to correct the patient's mandibular protrusion and facial asymmetry. The total treatment period was 30 months, and the final result was improvement of the patient's facial appearance.