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Real-time reverse-transcriptase polymerase chain reaction (RT-PCR) has been the gold standard for diagnosing coronavirus disease 2019 (COVID-19) but has a lag time for the results. An effective prediction algorithm for infectious COVID-19, utilized at the emergency department (ED), may reduce the risk of healthcare-associated COVID-19.
Objective:
To develop a prototypic prediction model for infectious COVID-19 at the time of presentation to the ED.
Material and methods:
Retrospective cohort study of all adult patients admitted to Singapore General Hospital (SGH) through ED between March 15, 2020, and December 31, 2022, with admission of COVID-19 RT-PCR results. Two prediction models were developed and evaluated using area under the curve (AUC) of receiver operating characteristics (ROC) to identify infectious COVID-19 patients (cycle threshold (Ct) of <25).
Results:
Total of 78,687 patients were admitted to SGH through ED during study period. 6,132 of them tested severe acute respiratory coronavirus 2 positive on RT-PCR. Nearly 70% (4,226 of 6,132) of the patients had infectious COVID-19 (Ct<25). Model that included demographics, clinical history, symptom and laboratory variables had AUROC of 0.85 with sensitivity and specificity of 80.0% & 72.1% respectively. When antigen rapid test results at ED were available and added to the model for a subset of the study population, AUROC reached 0.97 with sensitivity and specificity of 95.0% and 92.8% respectively. Both models maintained respective sensitivity and specificity results when applied to validation data.
Conclusion:
Clinical predictive models based on available information at ED can be utilized for identification of infectious COVID-19 patients and may enhance infection prevention efforts.
Birds in flight are prone to collide with various transparent or reflective structures. While bird–window collision has been recognised as a critical conservation issue, collision with other transparent structures has been less understood. Noise barriers made of transparent materials are considered critical hazards for birds; however, little is known about the bird mortality they cause. We conducted the first nationwide-scale estimates of bird-collision mortality caused by transparent noise barriers (TNBs) along roads in the Republic of Korea. The total length of existing roadside transparent noise barriers was estimated at 1,416 km nationwide (as of 2018), and it had been increasing exponentially. Based on carcass surveys at 25 sites, daily mortality at the observed barriers was 0.335 ± 1.132 birds/km on average, and no difference in observed mortality was detected between both sides of a single barrier and between road types (i.e. local roads and motorways). Finally, we estimated that approximately 186,000 birds (95% confidence interval: 162,465–204,812 birds) are killed annually by collisions with roadside TNBs. As privately installed barriers were not considered in this study, the actual mortality is likely be higher than our estimates. Thus, collision with TNBs could become an emerging threat to avian conservation, especially in developing and urbanising regions around the world. As such structures are not formally recognised as conservation issues of importance, more systematic surveys aided by citizen science, both for the status of TNBs and bird-collision mortality, are needed in addition to management and mitigation policies.
Predicting the course of depression is necessary for personalized treatment. Impaired glucose metabolism (IGM) was introduced as a promising depression biomarker, but no consensus was made. This study aimed to predict IGM at the time of depression diagnosis and examine the relationship between long-term prognosis and predicted results.
Methods
Clinical data were extracted from four electronic health records in South Korea. The study population included patients with depression, and the outcome was IGM within 1 year. One database was used to develop the model using three algorithms. External validation was performed using the best algorithm across the three databases. The area under the curve (AUC) was calculated to determine the model’s performance. Kaplan–Meier and Cox survival analyses of the risk of hospitalization for depression as the long-term outcome were performed. A meta-analysis of the long-term outcome was performed across the four databases.
Results
A prediction model was developed using the data of 3,668 people, with an AUC of 0.781 with least absolute shrinkage and selection operator (LASSO) logistic regression. In the external validation, the AUCs were 0.643, 0.610, and 0.515. Through the predicted results, survival analysis and meta-analysis were performed; the hazard ratios of risk of hospitalization for depression in patients predicted to have IGM was 1.20 (95% confidence interval [CI] 1.02–1.41, p = 0.027) at a 3-year follow-up.
Conclusions
We developed prediction models for IGM occurrence within a year. The predicted results were related to the long-term prognosis of depression, presenting as a promising IGM biomarker related to the prognosis of depression.
We calculated the human resources required for an antimicrobial stewardship program (ASP) in Korean hospitals.
Design:
Multicenter retrospective study.
Setting:
Eight Korean hospitals ranging in size from 295 to 1,337 beds.
Methods:
The time required for performing ASP activities for all hospitalized patients under antibiotic therapy was estimated and converted into hours per week. The actual time spent on patient reviews of each ASP activity was measured with a small number of cases, then the total time was estimated by applying the determined times to a larger number of cases. Full-time equivalents (FTEs) were measured according to labor laws in Korea (52 hours per week).
Results:
In total, 225 cases were reviewed to measure time spent on patient reviews. The median time spent per patient review for ASP activities ranged from 10 to 16 minutes. The total time spent on the review for all hospitalized patients was estimated using the observed number of ASP activities for 1,534 patients who underwent antibiotic therapy on surveillance days. The most commonly observed ASP activity was ‘review of surgical prophylactic antibiotics’ (32.7%), followed by ‘appropriate antibiotics recommendations for patients with suspected infection without a proven site of infection but without causative pathogens’ (28.6%). The personnel requirement was calculated as 1.20 FTEs (interquartile range [IQR], 1.02–1.38) per 100 beds and 2.28 FTEs (IQR, 1.93–2.62) per 100 patients who underwent antibiotic therapy, respectively.
Conclusion:
The estimated time required for human resources performing extensive ASP activities on all hospitalized patients undergoing antibiotic therapy in Korean hospitals was ~1.20 FTEs (IQR, 1.02–1.38) per 100 beds.
The aim of this study is to develop predictive models to predict organ at risk (OAR) complication level, classification of OAR dose-volume and combination of this function with our in-house developed treatment decision support system.
Materials and methods
We analysed the support vector machine and decision tree algorithm for predicting OAR complication level and toxicity in order to integrate this function into our in-house radiation treatment planning decision support system. A total of 12 TomoTherapyTM treatment plans for prostate cancer were established, and a hundred modelled plans were generated to analyse the toxicity prediction for bladder and rectum.
Results
The toxicity prediction algorithm analysis showed 91·0% accuracy in the training process. A scatter plot for bladder and rectum was obtained by 100 modelled plans and classification result derived. OAR complication level was analysed and risk factor for 25% bladder and 50% rectum was detected by decision tree. Therefore, it was shown that complication prediction of patients using big data-based clinical information is possible.
Conclusion
We verified the accuracy of the tested algorithm using prostate cancer cases. Side effects can be minimised by applying this predictive modelling algorithm with the planning decision support system for patient-specific radiotherapy planning.
Personality may predispose family caregivers to experience caregiving differently in similar situations and influence the outcomes of caregiving. A limited body of research has examined the role of some personality traits for health-related quality of life (HRQoL) among family caregivers of persons with dementia (PWD) in relation to burden and depression.
Methods:
Data from a large clinic-based national study in South Korea, the Caregivers of Alzheimer's Disease Research (CARE), were analyzed (N = 476). Path analysis was performed to explore the association between family caregivers’ personality traits and HRQoL. With depression and burden as mediating factors, direct and indirect associations between five personality traits and HRQoL of family caregivers were examined.
Results:
Results demonstrated the mediating role of caregiver burden and depression in linking two personality traits (neuroticism and extraversion) and HRQoL. Neuroticism and extraversion directly and indirectly influenced the mental HRQoL of caregivers. Neuroticism and extraversion only indirectly influenced their physical HRQoL. Neuroticism increased the caregiver's depression, whereas extraversion decreased it. Neuroticism only was mediated by burden to influence depression and mental and physical HRQoL.
Conclusions:
Personality traits can influence caregiving outcomes and be viewed as an individual resource of the caregiver. A family caregiver's personality characteristics need to be assessed for tailoring support programs to get the optimal benefits from caregiver interventions.
It is controversial whether Borna disease virus (BDV) infects humans and causes psychiatric disorders.
Objectives:
The relationship between BDV infection and schizophrenia with deficit syndrome was investigated.
Study design:
Using the Schedule for the Deficit Syndrome, 62 schizophrenic in-patients were selected from three psychiatric hospitals. RNA was extracted from peripheral blood mononuclear cells and analyzed using nested reverse transcriptase-polymerase chain reaction with primers to detect BDV p24 and p40.
Results and conclusions:
BDV transcripts were not detected in samples from any of the 62 schizophrenic patients. These data do not support an etiologic association between BDV infection and the deficit form of schizophrenia.
Using immunostaining methodology, we traced the axonal projection of FMRFamide (Phe-Met-Arg-Phe-NH2)-like immunoreactive (LI) medial neurosecretory cells (MNCs) and lateral neurosecretory cells (LNCs) from the brain into the ventral nerve cord (VNC) and retrocerebral complex in Bombyx mori (L.) (Lepidoptera: Bombycidae). Of the seven pairs of FMRFamide-LI MNCs, one pair extended its axons from the brain pars intercerebralis into the VNC ipsilateral connective where they appeared to terminate. The axons of the remaining MNCs ran through decussation in the brain median region and contralateral nervi corporis cardiaci (NCC) I out of the brain, and eventually innervated the contralateral corpus cardiacum (CC). Axons from the single pair of FMRFamide-LI LNCs projected into the ipsilateral NCC II fused with NCC I without decussation in the brain, and finally terminated in the CC. These results suggest that transport of the FMRFamide-like neuropeptide from may be related to the modulation of functions such as gut contraction in MNCs terminating in the VNC, and regulation of production and/or secretion of specific hormones such as juvenile hormone in MNCs and LNCs terminating in the CC.
Accumulated evidence suggests that social support is influenced by genetic and environmental factors. However, there are little data that examine this issue from Asian samples. We reported results from a preliminary study that examined familial effects on social support in a Chinese adult twin sample. We administered a 10-item social support instrument that measures three dimensions of social support (i.e., objective support, subjective support, and utilization of support) developed for the Chinese population. Two hundred forty-two same-sex twin pairs, where both members of the pair completed the personal interview, were included in the final analysis. Structural equation modeling was used to estimate additive genetic (A), shared environmental (C), and nonshared environmental (E) effects on each dimension of social support. Familial factors (A+C) explained 56.63% [95% CI = 45.48–65.72%] and 42.42% [95% CI = 29.93–53.25%] of the total phenotypic variances of subjective support and utilization of support, respectively. For the objective support, genetic effects did not exist, but common environmental effect explained 37.56% [95% CI = 26.17–48.28%] of the total phenotypic variances. Neither gender nor age effects were seen on any dimension of social support. Except for objective support, genetic factors probably influence variation in subjective support and utilization of support. Shared environmental factors may influence all dimensions of social support.
We performed this study to investigate the effect of histone deacetylase inhibition during extended culture of in vitro matured mouse oocytes. In vitro matured mouse (BDF1) oocytes were cultured in vitro for 6, 12, and 24 h, respectively, and then inseminated. During in vitro culture for 6 and 12 h, two doses of trichostatin A (TSA), a histone deacetylase inhibitor, were added (100 nM and 500 nM) to the culture medium and the oocytes were then inseminated. During the 24-h in vitro culture, two doses of TSA were added (100 nM and 500 nM) to the medium and the oocytes were activated with 10 mM SrCl2. After the 6-h culture, the fertilization rate was similar to that of the control group, but the blastocyst formation rate was significantly decreased. After the 12-h culture, both the fertilization and blastocyst formation rates were significantly decreased. After the 24-h culture, total fertilization failure occurred. In the oocytes cultured for 6 and 12 h, the fertilization and blastocyst formation rates did not differ between the TSA-supplemented and control groups. Although extended culture of the mouse oocytes significantly affected their fertilization and embryo development, TSA supplementation did not overcome their decreased developmental potential.
Cocoa polyphenols have antioxidant and anti-inflammatory effects. TNF-α is a pro-inflammatory cytokine that has a vital role in the pathogenesis of inflammatory diseases such as cancer and psoriasis. Vascular endothelial growth factor (VEGF) expression is associated with tumorigenesis, CVD, rheumatoid arthritis and psoriasis. We tested whether cocoa polyphenol extract (CPE) inhibited TNF-α-induced VEGF expression in promotion-sensitive JB6 mouse epidermal cells. CPE significantly inhibited TNF-α-induced up-regulation of VEGF via reducing TNF-α-induced activation of the nuclear transcription factors activator protein-1 (AP-1) and NF-κB, which are key regulators of VEGF expression. CPE also inhibited TNF-α-induced phosphorylation of protein kinase B (Akt) and extracellular signal-regulated kinase. CPE blocked activation of their downstream kinases, p70 kDa ribosomal protein S6 kinase and p90 kDa ribosomal protein S6 kinase. CPE suppressed phosphoinositide 3-kinase (PI3K) activity via binding PI3K directly. CPE did not affect TNF-α-induced phosphorylation of mitogen-activated protein kinase kinase-1 (MEK1) but suppressed TNF-α-induced MEK1 activity. Collectively, these results indicate that CPE reduced TNF-α-induced up-regulation of VEGF by directly inhibiting PI3K and MEK1 activities, which may contribute to its chemopreventive potential.
We evaluated the effects of the two main kiwifruit cultivars (gold kiwifruit (GOK) and green kiwifruit (GRK)) and their active phenolic compound, quercetin, on H2O2-induced inhibition of gap-junction intercellular communication (GJIC) in WB-F344 rat liver epithelial cells. We found that both GOK and GRK protect WB-F344 cells from H2O2-induced inhibition of GJIC. The extracellular signal-regulated protein kinase 1/2 (ERK1/2)–connexin 43 (Cx43) signalling pathway is crucial for the regulation of GJIC, and both GOK and GRK blocked the H2O2-induced phosphorylation of Cx43 and ERK1/2 in WB-F344 cells. Quercetin alone attenuated the H2O2-mediated ERK1/2–Cx43 signalling pathway and consequently reversed H2O2-mediated inhibition of GJIC in WB-F344 cells. A free radical-scavenging assay using 1,1-diphenyl-2-picrylhydrazyl showed that the scavenging activity of quercetin was higher than that of a synthetic antioxidant, butylated hydroxytoluene, per mol, suggesting that the chemopreventive effect of quercetin on H2O2-mediated inhibition of ERK1/2–Cx43 signalling and GJIC may be mediated through its free radical-scavenging activity. Since the carcinogenicity of reactive oxygen species such as H2O2 is attributable to the inhibition of GJIC, GOK, GRK and quercetin may have chemopreventive potential by preventing the inhibition of GJIC.
To describe the incidence of recovery of both vancomycin-resistant enterococci (VRE) and methicillin-resistant Staphylococcus aureus (MRSA) from culture of a single clinical specimen, to describe the clinical characteristics of patients from whom these specimens were recovered, and to identify the risk factors of these patients.
Design.
A retrospective cohort and case-control study.
Setting.
A tertiary care university hospital and referral center in Seoul, Korea.
Methods.
We identified 61 case patients for whom a single clinical specimen yielded both VRE and MRSA on culture, and 122 control patients for whom any clinical specimen yielded only VRE on culture. The control patients were selected by matching 2 :1 with the case patients for age, sex, and first date of sampling that led to isolation of VRE or both VRE and MRSA among 1,536 VRE-colonized patients from January 1, 2003, through December 31, 2006. To identify patient risk factors for the recovery of both VRE and MRSA in a single clinical specimen, we performed univariate comparisons between the 2 groups and then multivariate logistic regression analysis.
Results.
The incidence of recovery of both VRE and MRSA from culture of a single clinical specimen was 3.97% (for 61 of 1,536 VRE-colonized patients) over 4 years. Among these 82 single clinical specimens, the most common type was wound specimens (26.8%), followed by lower respiratory tract specimens (18.3%), urine specimens (17.1%), and catheter tips (15.9%). Of the 61 case patients, 14 (23.0%) had 2 or more single clinical specimens that yielded both VRE and MRSA on culture, and the longest interval from the first sampling that yielded both organisms to the last sampling that yielded both was 174 days. Independent patient risk factors for the presence of both VRE and MRSA in a single clinical specimen were chronic renal disease (odds ratio [OR], 7.00; P = .012), urinary catheterization (OR, 3.36; P = .026), and longer total cumulative duration of hospital stay within the previous year (OR, 1.03; P < .001).
Conclusion.
We confirmed that the recovery of VRE and MRSA from a single clinical specimen occurs continually. Because prolonged cell-to-cell contact can facilitate transfer of vanA, close observation and surveillance for vancomycin-resistant S. aureus, especially among patients with risk factors for the recovery of both VRE and MRSA from a single clinical specimen, should be continued.
We investigate boron transient enhanced diffusion (TED) and series resistance in SiGe/Si heterojunction channel pMOSFET. The stress gradient at the SiGe/Si interface near the gate edge in high Ge concentrations are found to determine boron TED as well as extension junction shape, which has a significant impact on the parasitic LDD and source/drain (S/D) series resistance. In addition, high Ge concentrations in the epitaxial SiGe layer on top of Si substrate result in a high sheet resistance during a 1000°C/5s rapid thermal processing (RTP), which is mainly due to alloy scattering and interface roughness scattering.
A novel route to organic-inorganic composites was described based on biomineralization of poly(ethylene glycol) (PEG)-based hydrogels. The 3-dimensional hydrogels were synthesized by radical crosslinking polymerization of poly(ethylene glycol fumarate) (PEGF) in the presence of ethylene glycol methacrylate phosphate (EGMP) as an apatite-nuclating monomer, acrylamide (AAm) as a composition-modulating comonomer, and potassium persulfate (PPS) as a radical initiator. We used the urea-mediated solution precipitation technique for biomineralization of hydrogels. The apatite grown on the surface and interior of the hydrogel was similar to biological apatites in the composition and crystalline structure. Powder x-ray diffraction (XRD) showed that the calcium phosphate crystalline platelets on hydrogels are preferentially aligned along the crystallographic c-axis direction. Inductively-coupled plasma mass spectroscopy (ICP-MS) analysis showed that the Ca/P molar ratio of apatites grown on the hydrogel template was found to be 1.60, which is identical to that of natural bones. In vitro cell experiments showed that the cell adhesion/proliferation on the mineralized hydrogel was more pronounced than on the pure polymer hydrogel.
To improve the IPD reliability of NAND flash memory, plasma oxidation was introduced as the post-treatment process of ONO (Oxide/Nitride/Oxide) IPD. The LP-CVD SiO2 modified by plasma oxidation showed the excellent electrical properties. e.g., low leakage current, high breakdown voltage etc. By the analysis of Tof-SIMS and XRR, we could observe the several changes of physical characteristics such as the reduction of impurities (H, N etc.), the increase of oxide density, and the improvement of oxide surface roughness. We found out the appropriate treatment condition to be able to densify oxide layer without the addition of ONO Equivalent Oxide Thickness (EOT). The LP-CVD SiO2 prepared by plasma oxidation was used for the ONO IPD of 50nm NAND flash device and also compared with the conventional LP-CVD SiO2 in the aspect of the IPD reliability.
The in-situ SEM observation of real-time hillock evolution in pure Al thin films on glass substrate during isothermal annealing at 194°C was analyzed quantitatively to understand the compressive stress relaxation mechanism by focusing on the effect of Mo interlayer between Al film and glass substrate. There is a good correlation between the hillock-induced stress relaxation and the measured stress relaxation by wafer curvature method. It is also clearly shown that the existence of Mo interlayer plays an important role in hillock formation probably due to the large difference in interfacial diffusivity of Al films.
Silicon carbide (SiC) microtubes were synthesized and characterized via a vapor–solid (VS) reaction of carbon fiber (Csolid) and SiO(gas). The synthesis mechanisms were investigated. The precursor led complete conversion of [SiO(gas) + C(solid)] into [SiC(solid) + CO(gas)] through overall reaction under inert gas flow at and above 1350 °C. Carbon fibers with small surface area (0.7–2.0 m2 g−1) were gradually converted to SiC microtubes with large specific surface area (45–63 m2 g−1). Inner surface of SiC microtubes indicated a villus-like morphology, which consisted of submicron-sized SiC villi. The outer surface of the SiC microtubes was smooth. Inner surface morphology of SiC microtubes was dependent upon synthesizing temperature. Thickness of villus-like layer in SiC microtubes increased with increasing synthesizing temperature, showing 0.25 and 0.5 at 1350 and 1400 °C, respectively. Both VS and gas–liquid–solid (VLS) growth mechanisms were investigated in synthesis of SiC fiber as a reaction byproduct, and the reaction was governed by both growth mechanisms.