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Previous evidence on antidepressant medication and cardiovascular disease (CVD) among patients with posttraumatic stress disorder (PTSD) has been inconclusive. We estimated the association between antidepressant medication and CVD by applying a marginal structural model.
We analyzed medical utilization records of 27 170 people with PTSD without prior major cardiovascular events in the Korean National Health Insurance Database (NHID). PTSD and CVD were defined in accordance with the recorded ICD-10 diagnostic codes. We acquired information on antidepressant use from the NHID and categorized them by medication type. A composite major adverse cardiovascular events (MACE) outcome was defined as coronary artery disease with revascularization, ischaemic stroke, and/or haemorrhagic stroke. We used inverse probability of treatment weighting to estimate the parameters of a marginal structural discrete-time survival analysis regression model, comparing the resulting estimates to those derived from traditional time-fixed and time-varying Cox proportional hazards regression. We calculated cumulative daily defined doses to test for a dose–response relationship.
People exposed to antidepressants showed a higher hazard of MACE [hazard ratio (HR) 1.34, 95% confidence interval (CI) 1.18–1.53]. The estimated effects were strongest for selective serotonin reuptake inhibitors (HR 1.24, 95% CI 1.08–1.44) and TCAs (HR 1.33, 95% CI 1.13–1.56). Exposure to serotonin-norepinephrine reuptake inhibitors did not appear to increase the risk of MACE. People exposed to higher doses of antidepressants showed higher risk of MACE.
In a national cohort of people with PTSD, exposure to antidepressant medications increased the risk of MACE in a dose–response fashion.
This paper studies the sustainability of plastrons on superhydrophobic (SHPo) surfaces made of longitudinal micro-trenches covered by nano-grass with the main interest on hydrodynamic friction drag reduction in high-speed flows of open water, which represent the operating conditions of common watercraft. After revising the shear-driven drainage model to address the air diffusion for SHPo surfaces, the existing theories are combined to reveal the trends of how the immersion depth, air saturation level and shear stress affect the maximum attainable plastron length. Deviations from the theories by the dynamic effect at the two ends of the trench, the interfacial contaminations and turbulent fluctuation are also discussed. A combinatorial series of well-defined SHPo trench surfaces (4 cm × 7 cm in size with varying trench widths, depths, lengths and roughnesses) is microfabricated and attached underneath a 4 m long motorboat on seawater in turbulent flows up to 7.2 m s−1 (shear rate ∼83 000 s−1 and friction Reynolds number ∼5500). Because the plastron can provide a substantial slip only while its air–water interfaces are pinned (or only slightly depinned) at the trench top, two underwater cameras are employed to differentiate the pinned (and slightly depinned) interfaces from the depinned (and no) interfaces. In addition to achieving pinned plastrons on 6 cm long trenches aligned to high-speed flows in open water, the experimental results corroborate the theoretical estimations, supporting the design of SHPo surfaces for field applications.
Litter-dwelling arthropods play an important role in maintaining forest ecosystem function. This study was designed to understand seasonal variations and diversity of litter-dwelling adult beetles, one of the most diverse groups of arthropods. Sampling was conducted in mixed-wood forests of South Korea between March and December 2019, covering all seasons, including winter. We used a sifting method and a Berlese funnel to collect arthropods living in leaf litter and soil. We collected a total of 5820 invertebrates representing six orders, of which 1422 were beetles representing 24 families and minimum 141 species. Beetle species richness was highest in spring and lowest in summer based on rarefaction and extrapolation. However, beetle abundance was lowest in spring, but abundance was similar among the other seasons. Beetle assemblage composition was correlated significantly with soil surface and atmospheric temperature. The assemblage composition differed among seasons, except between spring and winter, which overlapped slightly. The combined sifting–Berlese funnel method showed great advantages for investigating the diversity of overwintering arthropods. Continued study of the relationship between arthropods and the leaf-litter environment is essential to understand this microecosystem and will increase the chance of discovering new beetle species.
Two aphid-transmitted RNA viruses, broad bean wilt virus 2 (BBWV2) and cucumber mosaic virus (CMV), are the most prevalent viruses in Korean pepper fields and cause chronic damage in pepper production. In this study, we employed a screening system for pathotype-specific resistance of pepper germplasm to BBWV2 and CMV by utilizing infectious cDNA clones of different pathotypes of the viruses (two BBWV2 strains and three CMV strains). We first examined pathogenic characteristics of the BBWV2 and CMV strains in various plant species and their phylogenetic positions in the virus population structures. We then screened 34 commercial pepper cultivars and seven accessions for resistance. While 21 pepper cultivars were resistant to CMV Fny strain, only two cultivars were resistant to CMV P1 strain. We also found only one cultivar partially resistant to BBWV2 RP1 strain. However, all tested commercial pepper cultivars were susceptible to the resistance-breaking CMV strain GTN (CMV-GTN) and BBWV2 severe strain PAP1 (BBWV2-PAP1), suggesting that breeding new cultivars resistant to these virus strains is necessary. Fortunately, we identified several pepper accessions that were resistant or partially resistant to CMV-GTN and one symptomless accession despite systemic infection with BBWV2-PAP1. These genetic resources will be useful in pepper breeding programs to deploy resistance to BBWV2 and CMV.
To evaluate the impact of a vancomycin-resistant Enterococcus (VRE) screening policy change on the incidence of healthcare-associated (HA)-VRE bacteremia in an endemic hospital setting.
A quasi-experimental before-and-after study.
A 1,989-bed tertiary-care referral center in Seoul, Republic of Korea.
Since May 2010, our hospital has diminished VRE screening for admitted patients transferred from other healthcare facilities. We assessed the impact of this policy change on the incidence of HA-VRE bacteremia using segmented autoregression analysis of interrupted time series from January 2006 to December 2014 at the hospital and unit levels. In addition, we compared the molecular characteristics of VRE blood isolates collected before and after the screening policy change using multilocus sequence typing and pulsed-field gel electrophoresis.
After the VRE screening policy change, the incidence of hospital-wide HA-VRE bacteremia increased, although no significant changes of level or slope were observed. In addition, a significant slope change in the incidence of HA-VRE bacteremia (change in slope, 0.007; 95% CI, 0.001–0.013; P = .02) was observed in the hemato-oncology department. Molecular analysis revealed that various VRE sequence types appeared after the policy change and that clonally related strains became more predominant (increasing from 26.1% to 59.3%).
The incidence of HA-VRE bacteremia increased significantly after VRE screening policy change, and this increase was mainly driven by high-risk patient populations. When planning VRE control programs in hospitals, different approaches that consider risk for severe VRE infection in patients may be required.
The National Institute of Neurological Disease and Stroke-Canadian Stroke Network (NINDS-CSN) 5-minute neuropsychology protocol consists of only verbal tasks, and is proposed as a brief screening method for vascular cognitive impairment. We evaluated its feasibility within two weeks after stroke and ability to predict the development of post-stroke dementia (PSD) at 3 months after stroke.
We prospectively enrolled subjects with ischemic stroke within seven days of symptom onset who were consecutively admitted to 12 university hospitals. Neuropsychological assessments using the NINDS-CSN 5-minute and 60-minute neuropsychology protocols were administered within two weeks and at 3 months after stroke onset, respectively. PSD was diagnosed with reference to the American Heart Association/American Stroke Association statement, requiring deficits in at least two cognitive domains.
Of 620 patients, 512 (82.6%) were feasible for the NINDS-CSN 5-minute protocol within two weeks after stroke. The incidence of PSD was 16.2% in 308 subjects who had completed follow-up at 3 months after stroke onset. The total score of the NINDS-CSN 5-minute protocol differed significantly between those with and without PSD (4.0 ± 2.7, 7.4 ± 2.7, respectively; p < 0.01). A cut-off value of 6/7 showed reasonable discriminative power (sensitivity 0.82, specificity 0.67, AUC 0.74). The NINDS-CSN 5-minute protocol score was a significant predictor for PSD (adjusted odds ratio 6.32, 95% CI 2.65–15.05).
The NINDS-CSN 5-minute protocol is feasible to evaluate cognitive functions in patients with acute ischemic stroke. It might be a useful screening method for early identification of high-risk groups for PSD.
To evaluate the appropriateness of the screening strategy for healthcare personnel (HCP) during a hospital-associated Middle East Respiratory Syndrome (MERS) outbreak, we performed a serologic investigation in 189 rRT-PCR–negative HCP exposed and assigned to MERS patients. Although 20%–25% of HCP experienced MERS-like symptoms, none of them showed seroconversion by plaque reduction neutralization test (PRNT).
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.
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 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.
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.
During the past decade, carbapenemase-producing Enterobacteriaceae (CPE) has emerged and spread across the world.1 The major carbapenemase enzymes currently being reported are KPC, NDM-1, VIM, IMP, and OXA.2 Because carbapenemase can be effectively transmitted via mobile genetic elements, and current therapeutic options for CPE infections are extremely limited, CPE may be one of the most serious contemporary threats to public health. However, very little is known about the characteristics of CPE carriage during hospitalization. The aims of this study were to investigate the clearance rate of CPE carriage and determine the number of consecutive negative cultures required to confirm CPE clearance. We also examined CPE transmission among hospitalized patients.
Infect. Control Hosp. Epidemiol. 2015;36(11):1361–1362
Visual hallucination (VH) is a common psychotic symptom in patients with Parkinson's disease (PD) and may be a significant predictor of cognitive impairment (CI) in such patients.
This study aimed to investigate the pattern of glucose metabolism of VH and the relationship between VH and CI in PD.
We studied 28 PD patients, including 15 with VH (PD-VH) and 13 without VH (PD-NVH). Of the 15 PD-VH patients, 8 patients had cognitive impairment (PD-VHCI) whereas 7 did not (PD-VHNCI). All patients underwent [18F] fluorodeoxyglucose positron emission tomography ([18F] FDG PET) followed by statistical parametric mapping (SPM) analyses.
Compared to the patients with PDNVH, PD-VHNCI patients showed glucose hypometabolism in the inferior and middle temporal cortices, fusiform gyri, and frontal areas, suggesting the involvement of the ventral visual pathway. Compared to the patients with PDNVH, PD-VHCI patients showed glucose hypometabolism in the temporoparietal association cortices with scattered frontal areas.
Dysfunction of ventral visual pathway involving the temporal lobe may play a key role in VH development in PD patients. The evolving distribution from the ventral visual pathway to more extensive posterior cortices in PD-VHCI patients suggests that VH may be a prodromal symptom occurring prior to CI in PD patients.
The RDA Genebank at the National Agrobiodiversity Center (NAAS, RDA, Republic of Korea) has conserved about 182,000 accessions in 1777 species and is working at preserving agricultural genetic resources for the conservation and sustainable utilization of genetic diversity. The detection of genetic variability in conserved resources is important for germplasm management, but the molecular evaluation tools providing genetic information are insufficient for underutilized crops, unlike those for major crops. In this regard, the Korean National Agrobiodiversity Center has been developing microsatellite markers for several underutilized crops. We designed 3640 primer pairs flanking simple sequence repeat (SSR) motifs for 6310 SSR clones in 21 crop species. Polymorphic loci were revealed in each species (7–36), and the mean ratio of polymorphic loci to all the loci tested was 12%. The average allele number was 5.1 (2.8–10.3) and the expected heterozygosity 0.51 (0.31–0.74). Some SSRs were transferable to closely related species, such as within the genera Fagopyrum and Allium. These SSR markers might be used for studying the genetic diversity of conserved underutilized crops.
Liposomal drug delivery products have been already commercialized in tumor therapeutics, which can realize passive tumor targeting via enhanced permeability and retention (EPR) effect resulting from the leaky tumor vasculature. To control drug release out of the liposomes, thermo-sensitive liposomes (TSLs) have been developed so that an abrupt exposure of highly concentrated drugs to tumor tissues was enabled by locally treated thermal stimuli. As interests upon TSL have increased along with ongoing clinical trials, some types of TSLs with different physical properties in pharmacokinetics and the mechanism of drug release have been formulated. However, there are few protocols established with a desirable heat source to maximize the efficacy of different TSLs as treating tumors. In this study, we examined different protocols for the most effective application of different TSLs to tumor therapy. First, we examined if enhancing the accumulation of TSLs within tumor tissues prior to bursting drugs out of TSLs could lead to increasing anti-tumor efficacy. Second, we compared the efficiency of two different heat sources on the use of TSL, a warm water bath (42°C) and high intensity focused ultrasound (HIFU). Our study suggests that the specified protocol be setup for TSLs with different physical properties to optimally function in tumor therapies.
Direct heteroarylation polymerization was employed to synthesize a novel low bandgap polymer, used as a p-type material of polymer photovoltaic cells. To achieve low bandgap of conjugated polymers, electron donor-acceptor (D-A) alternating strategy was used. The electron-donating 3-alkylthiophene and electron-withdrawing cyanothiophene were coupled to be polymerized via direct heteroarylation polymerization. The cyano moiety of the polymer backbone allowed a strong intermolecular interaction between neighboring chains and improved the structural perfection of the crystal structure on the substrate. The solar cell devices of ITO/PEDOT:PSS/P3HT:PCBM/LiF/Al were fabricated on ITO-coated glass substrate.
The liquid phase plasma reduction method has been applied to prepare silver nanoparticles from a solution of silver nitrate (AgNO3) using a bipolar pulsed electrical discharge system. The excited states of atomic silver, hydrogen and oxygen as well as the molecular bands of hydroxyl radicals were detected in the emission spectra. As the discharge duration increased up to 10 min, silver particle peaks produced by surface plasmon absorption were observed around 430 nm. Both the particle size and the particle numbers were observed to increase with the length of the plasma treatment time and with the initial AgNO3 concentration. Spherical nanoparticles of about 5–20 nm in size were obtained with the discharging time of 5 min, whereas aggregates of nanoparticles of about 10–50 nm in size were mainly produced with the discharging time of 20 min. The cationic surfactant of cetyltrimethylammonium bromide (CTAB) added with the CTAB/AgNO3 molar ratio of 30% was shown to inhibit nanoparticle aggregation.
Background: Highly educated participants with normal cognition show lower incidence of Alzheimer's disease (AD) than poorly educated participants, whereas longitudinal studies involving AD have reported that higher education is associated with more rapid cognitive decline. We aimed to evaluate whether highly educated amnestic mild cognitive impairment (aMCI) participants show more rapid cognitive decline than those with lower levels of education.
Methods: A total of 249 aMCI patients enrolled from 31 memory clinics using the standard assessment and diagnostic processes were followed with neuropsychological evaluation (duration 17.2 ± 8.8 months). According to baseline performances on memory tests, participants were divided into early-stage aMCI (−1.5 to −1.0 standard deviation (SD)) and late-stage aMCI (below −1.5 SD) groups. Risk of AD conversion and changes in neuropsychological performances according to the level of education were evaluated.
Results: Sixty-two patients converted to AD over a mean follow-up of 1.43 years. The risk of AD conversion was higher in late-stage aMCI than early-stage aMCI. Cox proportional hazard models showed that aMCI participants, and late-stage aMCI participants in particular, with higher levels of education had a higher risk of AD conversion than those with lower levels of education. Late-stage aMCI participants with higher education showed faster cognitive decline in language, memory, and Clinical Dementia Rating Sum of Boxes (CDR-SOB) scores. On the contrary, early-stage aMCI participants with higher education showed slower cognitive decline in MMSE and CDR-SOB scores.
Conclusions: Our findings suggest that the protective effects of education against cognitive decline remain in early-stage aMCI and disappear in late-stage aMCI.
We demonstrate that the size and crystallinity of grains in individual ZnO nanofibers greatly influence their sensing properties for CO. The sensing properties, including sensitivity, response and recovery times of a sensor fabricated with ZnO nanofibers composed of large grains are much superior to those of a sensor fabricated with nanofibers of small grains. The crystallinity, improved by the longer calcination time, is likely to be responsible for the higher sensitivity in the large-grained nanofibers. The facilitated occupancy and desorption of CO molecules at grain boundaries in the large-grained nanofibers are the most probable causes of the shorter response and recovery times in detecting CO, respectively. This work suggests not only that electrospinning-synthesized ZnO nanofibers hold promise for realizing sensitive and reliable gas sensors but also that the size as well as the crystallinity of the grains existing in individual nanofibers need to be optimized to obtain the best sensing properties.
We have investigated the reliability of the inverted-staggered etch stopper structure oxide-based TFTs under negative gate bias stress combined with 400 nm wavelength light illumination and the relationship between the carrier concentration at the channel and the extent of Vth shift. It was found that the photo-induced holes cause the severe Vth degradation at the beginning of stress and the hole trapping rate of a single hole is not altered with the increase of the hole concentration. In oxide-based TFTs, the hole concentration at the channel is the determinant factor of the reliability.
Nitrogen-doped titania with a unique two-level hierarchical structure and visible light photocatalytic activity is reported. Thus, nitrogen-doped titanium oxide microrods decorated with N-doped titanium oxide nanosheets were synthesized by a hydrothermal reaction in NH4OH and postcalcination. During the calcination, the in situ incorporation of nitrogen atoms of ammonium ion into titania lattice was accompanied by the structural evolution from titanate to anatase titania. The morphological and structural evolution was monitored by scanning electron microscopy (SEM), x-ray diffraction (XRD), thermogravimetric analysis/differential thermal analysis (TGA/DTA), Raman, Fourier transform infrared (FTIR), x-ray absorption near edge structure (XANES), x-ray photoelectron spectroscopy (XPS), and adsorption isotherms. The N-doping brought visible light absorption, and the material exhibited high photocatalytic activity in the decomposition of Orange II under visible light irradiation (λ ≥ 400 nm), especially when it was loaded with 1 wt% Pt as a cocatalyst.