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Although disconnectivity among brain regions has been one of the main hypotheses for schizophrenia, the superficial white matter (SWM) has received less attention in schizophrenia research than the deep white matter (DWM) owing to the challenge of consistent reconstruction across subjects.
Methods:
We obtained the diffusion magnetic resonance imaging (dMRI) data of 223 healthy controls and 143 patients with schizophrenia. After harmonising the raw dMRIs from three different studies, we performed whole-brain two-tensor tractography and fibre clustering on the tractography data. We compared the fractional anisotropy (FA) of white matter tracts between healthy controls and patients with schizophrenia. Spearman’s rho was adopted for the associations with clinical symptoms measured by the Positive and Negative Syndrome Scale (PANSS). The Bonferroni correction was used to adjust multiple testing.
Results:
Among the 33 DWM and 8 SWM tracts, patients with schizophrenia had a lower FA in 14 DWM and 4 SWM tracts than healthy controls, with small effect sizes. In the patient group, the FA deviations of the corticospinal and superficial–occipital tracts were negatively correlated with the PANSS negative score; however, this correlation was not evident after adjusting for multiple testing.
Conclusion:
We observed the structural impairments of both the DWM and SWM tracts in patients with schizophrenia. The SWM could be a potential target of interest in future research on neural biomarkers for schizophrenia.
Blood carotenoid concentration measurement is considered the gold standard for fruit and vegetable (F&V) intake estimation; however, this method is invasive and expensive. Recently, skin carotenoid status (SCS) measured by optical sensors has been evaluated as a promising parameter for F&V intake estimation. In this cross-sectional study, we aimed to validate the utility of resonance Raman spectroscopy (RRS)-assessed SCS as a biomarker of F&V intake in Korean adults. We used data from 108 participants aged 20–69 years who completed SCS measurements, blood collection and 3-d dietary recordings. Serum carotenoid concentrations were quantified using HPLC, and dietary carotenoid and F&V intakes were estimated via 3-d dietary records using a carotenoid database for common Korean foods. The correlations of the SCS with serum carotenoid concentrations, dietary carotenoid intake and F&V intake were examined to assess SCS validity. SCS was positively correlated with total serum carotenoid concentration (r = 0·52, 95 % CI = 0·36, 0·64, P < 0·001), serum β-carotene concentration (r = 0·60, 95 % CI = 0·47, 0·71, P < 0·001), total carotenoid intake (r = 0·20, 95 % CI = 0·01, 0·37, P = 0·04), β-carotene intake (r = 0·30, 95 % CI = 0·11, 0·46, P = 0·002) and F&V intake (r = 0·40, 95 % CI = 0·23, 0·55, P < 0·001). These results suggest that SCS can be a valid biomarker of F&V intake in Korean adults.
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.
This study aimed to determine the effect of donor-transmitted atherosclerosis on the late aggravation of cardiac allograft vasculopathy in paediatric heart recipients aged ≥7 years.
Methods:
In total, 48 patients were included and 23 had donor-transmitted atherosclerosis (baseline maximal intimal thickness of >0.5 mm on intravascular ultrasonography). Logistic regression analyses were performed to identify risk factors for donor-transmitted atherosclerosis. Rates of survival free from the late aggravation of cardiac allograft vasculopathy (new or worsening cardiac allograft vasculopathy on following angiograms, starting 1 year after transplantation) in each patient group were estimated using the Kaplan–Meier method and compared using the log-rank test. The effect of the results of intravascular ultrasonography at 1 year after transplantation on the late aggravation of cardiac allograft vasculopathy, correcting for possible covariates including donor-transmitted atherosclerosis, was examined using the Cox proportional hazards model.
Results:
The mean follow-up duration after transplantation was 5.97 ± 3.58 years. The log-rank test showed that patients with donor-transmitted atherosclerosis had worse survival outcomes than those without (p = 0.008). Per the multivariate model considering the difference of maximal intimal thickness between baseline and 1 year following transplantation (hazard ratio, 22.985; 95% confidence interval, 1.948–271.250; p = 0.013), donor-transmitted atherosclerosis was a significant covariate (hazard ratio, 4.013; 95% confidence interval, 1.047–15.376; p = 0.043).
Conclusion:
Paediatric heart transplantation recipients with donor-transmitted atherosclerosis aged ≥7 years had worse late cardiac allograft vasculopathy aggravation-free survival outcomes.
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.
Design:
A quasi-experimental before-and-after study.
Setting:
A 1,989-bed tertiary-care referral center in Seoul, Republic of Korea.
Methods:
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.
Results:
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%).
Conclusions:
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.
Current evidence on antipsychotic treatment and risk of psychiatric hospitalization in first-episode schizophrenia (FES) is largely based on the findings from randomized clinical trials (RCTs). However, the generalization of the findings to real-world patients is limited due to inherent caveats of the RCT. We aimed to investigate the treatment discontinuation and risk of psychiatric hospitalization using a nationwide population database.
Methods
The Health Insurance Review Agency database in South Korea was obtained, and the observation period started from 1 January 2009 to 31 December 2016. We defined the maintenance period as the period from 6-month after the diagnosis of schizophrenia, which is utilized for the main results. For a total of 44 396 patients with FES, a within-individual Cox regression model was used to compare the risk of the treatment discontinuation and psychiatric hospitalization.
Results
In group comparison, a long-acting injectable (LAI) antipsychotic group was associated with the lowest risk of the treatment discontinuation (0.64, 0.55–0.75) and psychiatric hospitalization (0.29, 0.22–0.38) in comparison with a typical antipsychotic group and no use, respectively. Among individual antipsychotics, the lowest risk of the treatment discontinuation was observed in LAI paliperidone (0.46, 0.37–0.66) compared to olanzapine. Clozapine was found to be the most effective antipsychotic in lowering the risk of psychiatric hospitalization as monotherapy compared to no use (0.23, 0.18–0.31).
Conclusions
In real-world patients with FES, LAI paliperidone and clozapine were associated with low treatment discontinuation and better effectiveness in lowering the risk of psychiatric hospitalization.
Background: Recently, healthcare-associated infections (HAIs) in long-term care hospitals (LTCHs) have markedly increased, but no infection control policy has been established in South Korea. We investigated the current HAI surveillance system and executed a point-prevalence pilot study in LTCHs. Methods: HAIs were defined by newly established surveillance manual based on McGeer criteria revised in 2012. Three LTCHs in Seoul and Gyeonggi province were voluntarily recruited, and data were collected from up to 50 patients who were hospitalized on August 1. The medical records from September to November 2018 were retrospectively reviewed by a charge nurse for infection control per each hospitals after 1 day of training specific for LTCH surveillance. All data were reviewed by a senior researcher visiting onsite. Results: The participating hospitals had 272.33 ± 111.01 beds. Only 1 hospital had an onsite microbiological laboratory. In total, 156 patients were enrolled and 5 HAIs were detected, for a prevalence rate of 3.2%. The average patient age was 79.04 ± 9.92 years. The HAIs included 2 urinary tract infections, skin and soft-tissue infection, low respiratory infection, and conjunctivitis. Conclusions: This is the first survey of HAI in LTCHs in South Korea. The 3.2% prevalence rate is lower than those from previous reports from the European Union or the United States. This study supports the development of a national HAI surveillance and infection control system in LTCHs, although implementation may be limited due to the lack of laboratory support and infection control infrastructure in Korea.
We report our experience with an emergency room (ER) shutdown related to an accidental exposure to a patient with coronavirus disease 2019 (COVID-19) who had not been isolated.
Setting:
A 635-bed, tertiary-care hospital in Daegu, South Korea.
Methods:
To prevent nosocomial transmission of the disease, we subsequently isolated patients with suspected symptoms, relevant radiographic findings, or epidemiology. Severe acute respiratory coronavirus 2 (SARS-CoV-2) reverse-transcriptase polymerase chain reaction assays (RT-PCR) were performed for most patients requiring hospitalization. A universal mask policy and comprehensive use of personal protective equipment (PPE) were implemented. We analyzed effects of these interventions.
Results:
From the pre-shutdown period (February 10–25, 2020) to the post-shutdown period (February 28 to March 16, 2020), the mean hourly turnaround time decreased from 23:31 ±6:43 hours to 9:27 ±3:41 hours (P < .001). As a result, the proportion of the patients tested increased from 5.8% (N=1,037) to 64.6% (N=690) (P < .001) and the average number of tests per day increased from 3.8±4.3 to 24.7±5.0 (P < .001). All 23 patients with COVID-19 in the post-shutdown period were isolated in the ER without any problematic accidental exposure or nosocomial transmission. After the shutdown, several metrics increased. The median duration of stay in the ER among hospitalized patients increased from 4:30 hours (interquartile range [IQR], 2:17–9:48) to 14:33 hours (IQR, 6:55–24:50) (P < .001). Rates of intensive care unit admissions increased from 1.4% to 2.9% (P = .023), and mortality increased from 0.9% to 3.0% (P = .001).
Conclusions:
Problematic accidental exposure and nosocomial transmission of COVID-19 can be successfully prevented through active isolation and surveillance policies and comprehensive PPE use despite longer ER stays and the presence of more severely ill patients during a severe COVID-19 outbreak.
Here, we present an overview of how a tertiary hospital responded to maintain necessary activities and protect patients and staff from the coronavirus disease (COVID-19) outbreak.
Methods:
Gil Medical Center, a tertiary hospital in Incheon, has operated a special response team since January 21, 2020. All visitors were assessed for body temperature and respiratory symptoms, and screened for recent overseas travel. Suspected COVID-19 patients were taken to a screening clinic. All febrile patients with or without respiratory symptoms were taken to a respiratory safety clinic. An isolation ward, which consisted of 10 negative-pressure rooms, was used to treat confirmed cases. More than 120 beds were prepared for the outbreak, and patients with pneumonia were preemptively isolated.
Results:
By May 5, 480 960 visitors were assessed at the control station, 3350 patients visited the triage center, and 1794 were treated in the respiratory safety clinic. Seventeen confirmed cases were admitted to the negative isolation ward, and 350 patients with pneumonia were preemptively isolated. A total of 2977 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) polymerase chain reaction tests were performed.
Conclusions:
While tertiary hospitals play an important role in treating both COVID-19 patients and non-COVID-19 patients, hospital staff have to protect themselves from unexpected in-hospital transmission. A multifaceted response must be undertaken to protect tertiary hospitals and their staff during the COVID-19 epidemic.
Residual stress is generally evaluated using indentation by comparing the indentation curves of stressed and stress-free states. Here, we suggest a new method that can evaluate surface residual stress without indentation testing on stress-free specimen using stress-independent indentation parameters and an analysis of indentation contact morphology for the stress-free state. We found that several indentation parameters are independent of the stress by Vickers indentation testing on various stress states. The indentation contact morphology can be represented by indentation parameters including stress-independent ones, and by applying the stress-independent parameters obtained from the stressed state to the indentation contact depth function, we can estimate an indentation curve for stress-free state. The estimated curve matches well with the experimental stress-free indentation curve, and it was also confirmed that the applied stress values evaluated by comparing the estimated curve with the stressed indentation curve agree well with the reference values obtained from strain gauge.
We have investigated interfacial thermal resistance (ITR) between single-layer graphene and Cu substrate by using both experimental and numerical methods. For experiments, the micropipette sensing technique was utilized to measure the thermal conductivity of suspended graphene and temperature profile of supported graphene on Cu film subjected to heating with a point source continuous wave laser. The thermal conductivity of suspended single-layer graphene was measured to be 3492 ± 453 W/m°C from measurements of temperature profile on the suspended graphene. This intrinsic graphene thermal conductivity and the finite element method integrated with a multi-parameter fitting technique were used to estimate ITR between graphene and Cu film. In the multi-parameter fitting technique, the simulated temperature profile is compared with experimentally measured temperature profile on the supported graphene surface and the best-fitted parameters including thermal interface resistance was obtained. The estimated interface thermal resistance between single graphene and Cu substrate is 2.3 × 10−7 m2 K/W and the difference between experiment and simulation result during multi-parameter fitting is 6.9%.
We suggest a new method to evaluate stress directionality, the ratio of principal stresses, using nanoindentation by introducing a modified Berkovich indenter that is extended in one direction from the Berkovich indenter. In a nonequibiaxial stress state, the indentation load-depth curves are shifted differently as the extended axis of the indenter is placed in accordance with each principal direction. The indentation load-difference is proportional to each principal stress and the slopes are defined by the normal and parallel conversion factors whose ratio is constant at 0.58. The suggested method was verified by indentation tests using five nonequibiaxial stressed specimens. The evaluated stress directionality results show agreement with the applied reference values within ±20%. Furthermore, we calculated the conversion factor ratios for other modified Berkovich indenters extended to different degrees through finite element analysis and confirmed that the conversion factor ratio was inversely proportional to the extension of the modified Berkovich indenter.
In regression discontinuity (RD), a running variable (or “score”) crossing a cutoff determines a treatment that affects the mean-regression function. This paper generalizes this usual “one-score mean RD” in three ways: (i) considering multiple scores, (ii) allowing partial effects due to each score crossing its own cutoff, not just the full effect with all scores crossing all cutoffs, and (iii) accommodating quantile/mode regressions. This generalization is motivated by (i) many multiple-score RD cases, (ii) the full-effect identification needing the partial effects to be separated, and (iii) informative quantile/mode regression functions. We establish identification for multiple-score RD (MRD), and propose simple estimators that become “local difference in differences” in case of double scores. We also provide an empirical illustration where partial effects exist.
Objectives: Rotator cuff tear is the leading cause of the decline in quality of life for older adults, but comparative evidence on treatment effectiveness is lacking. This study systematically reviewed the effects of various rotator cuff tear treatments through a Bayesian meta-analysis of the related randomized clinical trials (RCTs).
Methods: We searched nine electronic databases for RCTs evaluating rotator cuff tear treatments from their inception through June 2017. A systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and the National Institute for Health and Care Excellence-Decision Support Unit guidelines (Supplementary Table 1). Outcomes included functional improvement, pain one year after surgical treatment, and tendon structural integrity. The Bayesian network meta-analysis was applied for functional improvement and pain, based on an assumption of consistency and similarity. Tendon integrity was reported descriptively.
Results: Fifteen RCTs were selected. Patients undergoing physiotherapy after open surgery showed statistically significant functional improvements compared with those undergoing physiotherapy only (mean differences, 9.1 [credible interval, 0.9–17.4]). Open surgery with physiotherapy was associated with a decrease in pain 1 year after treatment compared with when physiotherapy was combined with arthroscopic rotator cuff surgery, mini open surgery, platelet-rich plasma therapy, or physiotherapy alone (absolute value of mean difference 1.2 to 1.4). The tendon integrity results were inconsistent.
Conclusions: Some surgical treatments were associated with significant improvement in function and pain, but evidence regarding their comparative effectiveness is still lacking. A well-designed RCT discussing functional and structural treatment outcomes is needed in future.
Advancements in medical and surgical treatment have increased the life expectancy of patients with CHD. Many patients with CHD, however, struggle with the medical, psychosocial, and behavioural challenges as they transition from childhood to adulthood. Specifically, the environmental and lifestyle challenges in school are very important factors that affect children and adolescents with CHD. This study aimed to evaluate school-related adjustments depending on school level and disclosure of disease in children and adolescents with CHD. This was a descriptive and exploratory study with 205 children and adolescents, aged 7–18 years, who were recruited from two congenital heart clinics from 5 January to 27 February, 2015. Data were analysed using the Student’s t-test, analysis of variance, and a univariate general linear model. School-related adjustment scores were significantly different according to school level and disclosure of disease (p<0.001) when age, religion, experience being bullied, and parents’ educational levels were assigned as covariates. The school-related adjustment score of patients who did not disclose their disease dropped significantly in high school. This indicated that it is important for healthcare providers to plan developmentally appropriate educational transition programmes for middle-school students with CHD in order for students to prepare themselves before entering high school.
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.
Background: Patients diagnosed with Parkinson’s disease (PD) on clinics who subsequently turn out to have normal dopamine transporter images have been referred to as scans without evidence of dopaminergic deficits (SWEDDs) patients. Cardiovascular autonomic dysfunction has frequently been reported in PD. In this study, we determined the similarities and differences in cardiac autonomic dysfunction between SWEDDs and PD patients. This study investigated whether 24-hour ambulatory blood pressure monitoring (24-hour ABPM) can help identify possible cases with SWEDDs. Methods: We enrolled 28 SWEDDs patients, 46 patients with PD, and 30 healthy controls. To evaluate cardiac autonomic function, 24-hour ABPM was performed on all subjects. Cardiac metaiodobenzylguanidine (MIBG) scintigraphy was performed on the SWEDDs and PD subjects. Results: The percentage nocturnal decline in blood pressure differed significantly among SWEDDs patients, PD patients, and controls (p<0.05). In addition to the abnormal nocturnal BP, regulation (nondipping and reverse dipping) was significantly higher in SWEDDs and PD subjects than in the control subjects (p<0.05). There was no significant correlation between the % nocturnal blood pressure reduction and parameters of cardiac MIBG uptake ratio. However, orthostatic hypotension was significant correlated with the nocturnal blood pressure dip (%), nocturnal blood pressure patterns, and the cardiac MIBG uptake ratio (early and late) in combined SWEDDs and PD subjects. Conclusions: Pathologic nocturnal blood pressure regulation and nocturnal hypertension, known characteristics of PD, are also present in SWEDDs. Moreover, cardiac sympathetic denervation should not be attributed to cardiac autonomic dysfunction in SWEDDs patients. As with PD patients, the SWEDDs patients studied here tended to have cardiac autonomic dysfunction.
In this paper, we establish a translation theorem for the generalised analytic Feynman integral of functionals that belong to the Banach algebra ${\mathcal{F}}(C_{a,b}[0,T])$.