The impact of discontinuing single-room isolation of patients with vancomycin-resistant enterococci: a quasi-experimental single-centre study in South Korea

OBJECTIVES

There is limited data on the effects of discontinuing single-room isolation while maintaining contact precautions, such as the use of gowns and gloves. In April 2021, our hospital ceased single-room isolation for patients with vancomycin-resistant enterococci (VRE) because of single-room unavailability. This study assessed the impact of this policy by examining the incidence of hospital-acquired VRE bloodstream infections (HA-VRE BSI).

METHODS

This retrospective quasi-experimental study was conducted at a tertiary-care hospital in Seoul, South Korea. Time-series analysis was used to evaluate HA-VRE BSI incidence at the hospital level and in the haematology unit before (phase 1) and after (phase 2) the policy change.

RESULTS

At the hospital level, HA-VRE BSI incidence level (VRE BSI per 1000 patient-days per month) and trend did not change significantly between phase 1 and phase 2 (coefficient -0.015, 95% confidence interval (CI): -0.053 to 0.023, P=0.45 and 0.000, 95% CI: -0.002 to 0.002, P=0.84, respectively). Similarly, HA-VRE BSI incidence level and trend in the haematology unit (-0.285, 95% CI: -0.618 to 0.048, P=0.09 and -0.018, 95% CI: -0.036 to 0.000, P = 0.054, respectively) did not change significantly across the two phases.

CONCLUSIONS

Discontinuing single-room isolation of VRE-colonized or infected patients was not associated with an increase in the incidence of VRE BSI at the hospital level or among high-risk patients in the haematology unit. Horizontal intervention for multi-drug-resistant organisms, including measures such as enhanced hand hygiene and environmental cleaning, may be more effective at preventing VRE transmission.

Disease burden of bacteraemia with extended-spectrum beta-lactamase-producing and carbapenem-resistant Enterobacterales in Korea

BACKGROUND

Despite the significant impact of multi-drug-resistant bacteraemia, especially extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-E) and carbapenem-resistant Enterobacterales (CRE), the burden of disease has not been investigated thoroughly.

AIM

To evaluate the clinical outcomes and socio-economic burden of ESBL-E and CRE bacteraemia nationwide in the Republic of Korea.

METHODS

A search was undertaken for all cases of ESBL-E and CRE bacteraemia and matched controls in 10 hospitals in the Republic of Korea over 6 months. Patients with ESBL-E or CRE bacteraemia were classified as the R group, and matched controls with antibiotic-susceptible bacteraemia and without infection were classified as the S and N groups, respectively. Patients' clinical data were collected, and the economic burden was estimated based on medical expenses, loss of productivity and total costs.

FINDINGS

In total, 795 patients were identified, including 265 patients with ESBL-E or CRE bacteraemia and their matched controls. The mean total length of stay for patients with ESBL-E and CRE in the R group was 1.53 and 1.90 times that of patients in the S group, respectively. The 90-day mortality rates for ESBL-E in the R and S groups were 12.1% and 5.6%, respectively, and the corresponding figures for CRE were 28.6% and 12.0%. There were significant differences in the total costs between the R, S and N groups for both ESBL-E and CRE (ESBL-E: $11,151 vs $8712 vs $6063, P=0.004; CRE: $40,464 vs $8748 vs $7279, P=0.024).

CONCLUSION

The clinical and economic burden imposed by ESBL-E or CRE bacteraemia was extremely high. These findings suggest that efforts to control resistant bacteraemia are necessary to reduce this burden.

Neurodevelopmental profiles of 4-year-olds in the Navajo Birth Cohort Study

Objective

Native American children disproportionally face many risk factors for poor developmental outcomes; these factors include poverty, environmental toxicant exposure, and limited medical, and intervention services. To understand these risks, comprehensive documentation of developmental and behavioral phenotypes are needed. In the current descriptive study, we assessed the neurodevelopment of young Diné (Navajo) children using standardized assessment instruments in combination with expert clinician judgment.

Methods

As part of an ongoing, population-based, prospective birth cohort study, we conducted comprehensive neurodevelopmental assessments of 138, 3-5-year-old, Diné children residing on or near the Navajo Nation. We report results from standardized parent reports, psychiatric examinations, and direct assessments of children's language, cognitive, adaptive, and social-emotional development, as well as best estimate clinical diagnoses.

Results

Forty-nine percent of our sample met DSM-5 criteria for a neurodevelopmental disorder (NDD) diagnosis. Language and speech sound disorders were most common, although autism spectrum disorder (ASD) was also elevated compared to the general population. Though language performance was depressed amongst all groups of children with, and without, NDDs, those meeting criteria for certain NDDs performed significantly lower on all language measures, when compared to those without. Social-emotional, behavioral, and nonverbal cognitive ability were in the average range overall.

Conclusions

Diné children in our study were found to have a high percentage of clinically significant developmental delays. Overall, children presented with a pervasive pattern of depressed language performance across measures, irrespective of diagnosis (or no diagnosis), while other domains of functioning were similar to normative samples. Findings support the need to identify appropriate intervention and educational efforts for affected youth, while also exploring the causes of the specific developmental delays. However, longitudinal studies are necessary to establish best practices for identifying delays and delineating resilience factors to optimize development of Diné children.

Evaluation of Usefulness of Yeast-Based Biological Phantom and Preliminary Study for Verification of Hypoxic Effect of Flash Radiotherapy

PURPOSE/OBJECTIVE(S)

As a basic hypothesis for the effectiveness of flash radiation therapy, the effect of preserving normal tissue during flash radiation is due to the instantaneous chemical depletion of oxygen. A yeast-based biological phantom was created to verify the hypoxic effect of flash radiation therapy. A study to upgrade the previously developed X-Band LINAC to a flash irradiation mode is in progress, and a preceding study is conducted to evaluate the usefulness of a yeast-based biological phantom manufactured by analyzing the change in oxygen by irradiating a high dose in a general radiation therapy device.

MATERIALS/METHODS

Freeze-dried yeast sample (Saccharomyces cerevisiae, S288C) is activated and sub-cultured. For mass production of yeast samples, yeast culture medium is prepared by adding yeast colonies to the ypd medium. This study was conducted to verify the hypoxic effect among the biological mechanisms that occur during flash radiation therapy at the basic stage, and the oxygen concentration change during general radiation irradiation was measured in real time using a DO (Dissolved oxygen) meter and fiber optic sensor designed to do that. To prevent scatter, which is a concern during flash irradiation, the fiber form was used, and precise experiments are possible as a non-invasive oxygen concentration measurement method. Based on 10MV of general radiation therapy device, high-dose radiation of 500-10,000 cGy is irradiated to measure real-time oxygen concentration change.

RESULTS

As a result of irradiation with high-dose (500-10,000 cGy) radiation of general LINAC, it was confirmed that the oxygen concentration of the yeast culture medium decreased by 5.7-63.2%, and the usefulness of the biological phantom fabricated based on the yeast culture medium was evaluated.

CONCLUSION

Prior to the analysis of oxygen concentration change in yeast cells during X-Band LINAC flash irradiation, a preliminary study was conducted at a high dose in a general LINAC to obtain a significant result of oxygen concentration change and confirm the usefulness of the yeast-based biological phantom. Prior research was conducted and verified as a general irradiation experiment using a yeast-based biological phantom manufactured based on a DO meter and a fiber optic oxygen sensor. After irradiation with high-dose radiation, the oxygen concentration of the yeast culture medium was measured 5 times, and it was confirmed that there was a change in oxygen concentration of 5.7-63.2%, verifying the usefulness and stability of the biological phantom. The usefulness of the yeast-based biological phantom for high doses was confirmed, and it is expected that the usefulness of the biological phantom for flash radiation can be verified by additionally measuring the change in oxygen concentration of the biological phantom according to the high dose rate in the future.

Definitive Radiotherapy in Patients with Clinical T1N0M0 Esophageal Squamous Cell Carcinoma: A Multicenter Retrospective Study

PURPOSE/OBJECTIVE(S)

In this study, we aimed to assess the failure pattern and survival outcomes and to analyze the optimal treatment field of definitive RT for T1N0M0 esophageal squamous cell carcinoma (ESCC).

MATERIALS/METHODS

We performed a retrospective analysis in a multi-institutional cohort of patients with histologically confirmed T1N0M0 ESCC. We included patients who underwent RT with definitive aim from 2010 to 2019. Patterns of failure were demonstrated as in-field locoregional, out-field locoregional and distant metastasis. In the survival analysis, freedom from locoregional recurrence and their association with clinicopathologic risk factors were analyzed. We performed a propensity score matching in the cT1b patients to adjust for the heterogeneity of radiation technique, radiation dose and the use of concurrent chemotherapy.

RESULTS

A total of 168 patients were included with a median follow-up of 34.0 months, and there were 20 cT1a, 94 cT1b and 24 cT1x, (cT1, not otherwise specified) patients. The rates of all and locoregional failure were 26.9% and 23.1% for cT1a and 25.0% and 22.4% for cT1b patients. 10 (10.6%) patients experienced grade ≥ 3 adverse events. Among 116 cT1b patients, 69 patients received elective nodal irradiation (ENI) and 47 patients received involved field irradiation (IFI). After propensity score matching, the 3-year FFLRR rate was 84.5% (95% Confidence Interval, 71.0 - 92.1%). There was no significant difference between the ENI and IFI patients in FFLRR (Log-rank P = 0.831). In the multivariate analysis, the use of concurrent chemotherapy was the only factor marginally associated with FFLRR (Hazard ratio, 0.17; 95% CI, 0.02 - 1.13; P = 0.067).

CONCLUSION

cT1a patients who cannot receive endoscopic resection, showed similar rates of failure compared with cT1b patients, which questioned the accuracy of the staging and raised the need for through treatment such as chemoradiotherapy. In cT1b patients, IFI using dose of 50 to 60 Gy with concurrent chemotherapy could be a reasonable treatment option.

Familial Risk and Interaction With Smoking and Alcohol Consumption in Bladder Cancer: A Population-Based Cohort Study

Background

Although genetic factors are known to play a role in the pathogenesis of bladder cancer, population-level familial risk estimates are scarce. We aimed to quantify the familial risk of bladder cancer and analyze interactions between family history and smoking or alcohol consumption.

Methods

Using the National Health Insurance database, we constructed a cohort of 5,524,403 study subjects with first-degree relatives (FDRs) and their lifestyle risk factors from 2002 to 2019. Familial risk was calculated using hazard ratios (HRs) with 95% confidence intervals (CIs) that compare the risk of individuals with and without affected FDRs. Interactions between family history and smoking or alcohol intake were assessed on an additive scale using the relative excess risk due to interaction (RERI).

Results

Offspring with an affected parent had a 2.09-fold (95% CI: 1.41 - 3.08) increased risk of disease compared to those with unaffected parents. Familial risks of those with affected father and mother were 2.26 (95% CI: 1.51 - 3.39) and 1.10 (95% CI: 0.27 - 4.41), respectively. When adjusted for lifestyle factors, HR reduced slightly to 2.04 (95% CI: 1.38 - 3.01), suggesting that a genetic predisposition is the main driver in the familial aggregation. Smokers with a positive family history had a markedly increased risk of disease (HR: 3.60, 95% CI: 2.27 - 5.71), which exceeded the sum of their individual risks, with statistically significant interaction (RERI: 0.72, 95% CI: 0.31 - 1.13). For alcohol consumption, drinkers with a positive family history also had an increased risk of disease, although the interaction was not statistically significant (RERI: 0.05, 95% CI: -3.39 - 3.48).

Conclusion

Smokers and alcohol consumers with a positive family history of bladder cancer should be considered a high-risk group and be advised to undergo genetic counseling.

Familial risk of seropositive rheumatoid arthritis and interaction with smoking: a population-based cohort study

OBJECTIVES

We evaluated the familial risk of seropositive rheumatoid arthritis (RA) and examined interactions between family history and smoking.

METHODS

Using the National Health Insurance and Health Screening Program databases, which include information on familial relationships and lifestyle factors, we identified 5 524 403 individuals with first-degree relatives (FDRs) from 2002-2018. We calculated familial risk using hazard ratios (HRs) with 95% CIs which compare the risk of individuals with and without affected FDRs. Interactions between smoking and family history were assessed on an additive scale using the relative excess risk due to interaction (RERI).

RESULTS

Individuals with affected FDR had 4.52-fold (95% CI 3.98, 5.12) increased risk of disease compared with those with unaffected FDR. Familial risk adjusted for lifestyle factors decreased slightly (HR 4.49), suggesting that a genetic contribution is the predominant driver in the familial aggregation of RA. Smoking was associated with an increased risk of disease that was more pronounced among heavy (HR 1.92 95% CI 1.70, 2.18) compared with moderate (HR 1.15 95% CI 1.04, 1.28) smoking. In the interaction analysis, the risk associated with the combined effect of smoking and family history was higher than the sum of their individual effects, though statistically non-significant (RERI 1.30 95% CI ‒0.92, 3.51). Heavy smokers with a positive family history showed a prominent interaction (RERI 4.13 95% CI ‒0.88, 9.13) which exceeded moderate smokers (RERI 0.61 95% CI ‒1.90, 3.13), suggesting a dose-response interaction pattern.

CONCLUSION

Our findings indicate the possibility of an interaction between RA-associated genes and smoking.

Familial Risk of Gout and Interaction With Obesity and Alcohol Consumption: A Population-Based Cohort Study in Korea

OBJECTIVE

Population-based studies of the familial aggregation of gout are scarce, and gene/environment interactions are not well studied. This study was undertaken to evaluate the familial aggregation of gout as well as assess interactions between family history and obesity or alcohol consumption on the development of gout.

METHODS

Using the Korean National Health Insurance database, which includes information regarding familial relationships and risk factor data, we identified 5,524,403 individuals from 2002 to 2018. Familial risk was calculated using hazard ratios (HRs) with 95% confidence intervals (95% CIs) to compare the risk in individuals with and those without affected first-degree relatives. Interactions between family history and obesity/alcohol consumption were assessed on an additive scale using the relative excess risk due to interaction (RERI).

RESULTS

Individuals with a gout-affected first-degree relative had a 2.42-fold (95% CI 2.39, 2.46) increased risk of disease compared to those with unaffected first-degree relatives. Having both a family history of gout and being either overweight or having moderate alcohol consumption was associated with a markedly increased risk of disease, with HRs of 4.39 (95% CI 4.29, 4.49) and 2.28 (95% CI 2.22, 2.35), respectively, which exceeded the sum of their individual risks but was only statistically significant in overweight individuals (RERI 0.96 [95% CI 0.85, 1.06]). Obese individuals (RERI 1.88 [95% CI 1.61, 2.16]) and heavy drinkers (RERI 0.36 [95% CI 0.20, 0.52]) had a more prominent interaction compared to overweight individuals and moderate drinkers, suggesting a dose-response interaction pattern.

CONCLUSION

Our findings indicate the possibility of an interaction between gout-associated genetic factors and obesity/alcohol consumption.

Sociodemographic Differences in COVID-19 Pandemic Experiences Among Families in the United States

Importance

Few population-based studies in the US collected individual-level data from families during the COVID-19 pandemic.

Objective

To examine differences in COVID-19 pandemic-related experiences in a large sociodemographically diverse sample of children and caregivers.

Design, Setting, and Participants

The Environmental influences on Child Health Outcomes (ECHO) multi-cohort consortium is an ongoing study that brings together 64 individual cohorts with participants (24 757 children and 31 700 caregivers in this study) in all 50 US states and Puerto Rico. Participants who completed the ECHO COVID-19 survey between April 2020 and March 2022 were included in this cross-sectional analysis. Data were analyzed from July 2021 to September 2022.

Main Outcomes and Measures

Exposures of interest were caregiver education level, child life stage (infant, preschool, middle childhood, and adolescent), and urban or rural (population <50 000) residence. Dependent variables included COVID-19 infection status and testing; disruptions to school, child care, and health care; financial hardships; and remote work. Outcomes were examined separately in logistic regression models mutually adjusted for exposures of interest and race, ethnicity, US Census division, sex, and survey administration date.

Results

Analyses included 14 646 children (mean [SD] age, 7.1 [4.4] years; 7120 [49%] female) and 13 644 caregivers (mean [SD] age, 37.6 [7.2] years; 13 381 [98%] female). Caregivers were racially (3% Asian; 16% Black; 12% multiple race; 63% White) and ethnically (19% Hispanic) diverse and comparable with the US population. Less than high school education (vs master's degree or more) was associated with more challenges accessing COVID-19 tests (adjusted odds ratio [aOR], 1.88; 95% CI, 1.06-1.58), lower odds of working remotely (aOR, 0.04; 95% CI, 0.03-0.07), and more food access concerns (aOR, 4.14; 95% CI, 3.20-5.36). Compared with other age groups, young children (age 1 to 5 years) were least likely to receive support from schools during school closures, and their caregivers were most likely to have challenges arranging childcare and concerns about work impacts. Rural caregivers were less likely to rank health concerns (aOR, 0.77; 95% CI, 0.69-0.86) and social distancing (aOR, 0.82; 95% CI, 0.73-0.91) as top stressors compared with urban caregivers.

Conclusions

Findings in this cohort study of US families highlighted pandemic-related burdens faced by families with lower socioeconomic status and young children. Populations more vulnerable to public health crises should be prioritized in recovery efforts and future planning.

Adaptation of the Strength and Difficulties Questionnaire for Use in the Republic of Georgia

Background

Children in low-resource countries like Georgia often have limited access to assessment measures for mental health care services. This study adapts and validates the mental health screening tool the Strength and Difficulties Questionnaire for use in Georgian children.

Methods

A total of 16 654 children were assessed by a parent and/or teacher using Georgian-adapted Strength and Difficulties Questionnaire. Receiver operating characteristic analyses were performed to assess the discriminative validity of the Strength and Difficulties Questionnaires and to establish an optimal cutoff score.

Results

Data from 15 738 parents- and 13 560 teachers-administered Strength and Difficulties Questionnaire were analyzed. The internal consistency analysis showed Cronbach's alpha to be 0.625 and 0.621 for parent- and teacher-administered Strength and Difficulties Questionnaire, respectively. The area under the curve (95% CI) shows that the Strength and Difficulties Questionnaire can differentiate risk group children from typically developing peers: parent-administered questionnaires-0.629 (0.556-0.702) and teacher-administered questionnaires-0.680 (0.611-0.789). Parent-administered Strength and Difficulties Questionnaire has a cutoff value of 16 or more with 92.5% of sensitivity and teacher-administered Strength and Difficulties Questionnaire-14 or more with a sensitivity of 85.6%.

Conclusion

The study finds that the Strength and Difficulties Questionnaire is a valid screening instrument and does not depend on the informant-parent or teacher. It suggests that with appropriate cultural adaptation, the SDQ can be used in the Republic of Georgia to identify children at risk for mental disorders and help guide resource allocation.

Familial Risk of Graves' Disease among First-Degree Relatives and Interaction with Smoking: A Population-Based Study

OBJECTIVE

Population-based studies on the familial aggregation of Graves' disease (GD) are scarce and gene-environment interactions are not well-studied. We evaluated the familial aggregation of GD and assessed interactions between family history and smoking.

METHODS

Using the National Health Insurance database, which includes information on familial relationships and lifestyle risk factors, we identified 5,524,403 individuals with first-degree relatives (FDRs). Familial risk was calculated using hazard ratios (HRs), which compare the risk of individuals with and without affected FDRs. Interactions between smoking and family history were assessed on an additive scale using relative excess risk due to interaction (RERI).

RESULTS

The HR among individuals with affected FDRs was 3.39 (95% CI 3.30-3.48) compared to those without affected FDR, and among individuals with affected twin, brother, sister, father and mother the HRs were 36.53 (23.85-53.54), 5.26 (4.89-5.66), 4.12 (3.88-4.38), 3.34 (3.16-3.54), and 2.63 (2.53-2.74), respectively. Individuals with both a positive family history and smoking had an increased risk of disease (HR 4.68) with statistically significant interaction (RERI 0.94 95% CI 0.74-1.19). Heavy smokers with a positive family history showed a nearly 6-fold increased risk, which was higher than moderate smoking, suggesting a dose-response interaction pattern. Current smoking also showed a statistically significant interaction with family history (RERI 0.52 95% CI 0.22-0.82), while this was not observed for former smoking.

CONCLUSION

A gene-environment interaction can be suggested between smoking and GD-associated genetic factors, which diminishes after smoking cessation. Smokers with a positive family history should be considered a high-risk group and smoking cessation should be advised.

CRISIS AFAR: an international collaborative study of the impact of the COVID-19 pandemic on mental health and service access in youth with autism and neurodevelopmental conditions

BACKGROUND

Heterogeneous mental health outcomes during the COVID-19 pandemic are documented in the general population. Such heterogeneity has not been systematically assessed in youth with autism spectrum disorder (ASD) and related neurodevelopmental disorders (NDD). To identify distinct patterns of the pandemic impact and their predictors in ASD/NDD youth, we focused on pandemic-related changes in symptoms and access to services.

METHODS

Using a naturalistic observational design, we assessed parent responses on the Coronavirus Health and Impact Survey Initiative (CRISIS) Adapted For Autism and Related neurodevelopmental conditions (AFAR). Cross-sectional AFAR data were aggregated across 14 European and North American sites yielding a clinically well-characterized sample of N = 1275 individuals with ASD/NDD (age = 11.0 ± 3.6 years; n females = 277). To identify subgroups with differential outcomes, we applied hierarchical clustering across eleven variables measuring changes in symptoms and access to services. Then, random forest classification assessed the importance of socio-demographics, pre-pandemic service rates, clinical severity of ASD-associated symptoms, and COVID-19 pandemic experiences/environments in predicting the outcome subgroups.

RESULTS

Clustering revealed four subgroups. One subgroup-broad symptom worsening only (20%)-included youth with worsening across a range of symptoms but with service disruptions similar to the average of the aggregate sample. The other three subgroups were, relatively, clinically stable but differed in service access: primarily modified services (23%), primarily lost services (6%), and average services/symptom changes (53%). Distinct combinations of a set of pre-pandemic services, pandemic environment (e.g., COVID-19 new cases, restrictions), experiences (e.g., COVID-19 Worries), and age predicted each outcome subgroup.

LIMITATIONS

Notable limitations of the study are its cross-sectional nature and focus on the first six months of the pandemic.

CONCLUSIONS

Concomitantly assessing variation in changes of symptoms and service access during the first phase of the pandemic revealed differential outcome profiles in ASD/NDD youth. Subgroups were characterized by distinct prediction patterns across a set of pre- and pandemic-related experiences/contexts. Results may inform recovery efforts and preparedness in future crises; they also underscore the critical value of international data-sharing and collaborations to address the needs of those most vulnerable in times of crisis.

Adaptation of autism spectrum screening questionnaire (ASSQ) for use in Georgian school settings

Purpose

Even though 95% of children with neurodevelopmental disorders, including autism spectrum disorder (ASD), live in low- and middle-income countries, there is a dearth of studies from these countries, including the Republic of Georgia. Several ASD screening tools are available, but few are validated for use in Georgian or other smaller countries. This study aims to adapt and validate the autism spectrum screening questionnaire (ASSQ) for use in Georgia.

Design/methodology/approach

The ASSQ was administered for all third-grade students in 402 schools in the five main Georgian cities, n = 27,336. Prior to use, the 27-item ASSQ was translated, back-translated and adapted for use in Georgia. A total of 16,556 students (approximately 61%) were assessed by a parent and/or teacher. Optimal cutoff scores were estimated. Randomly chosen children who screened positive (n = 173) and negative (n = 127) were offered comprehensive assessment using standardized diagnostic procedures.

Findings

Data from 15,510 parents- and 13,517 teachers-administered ASSQ revealed statistically significant differences in median and cutoff scores between parents and teachers: 7 versus 4 and 9 versus 6, respectively. Cutoff score = 14, on either parent or teacher ASSQ, had sensitivity of 0.94, indicating that it can be used in school settings.

Originality/value

The Georgian adaptation of the ASSQ creates opportunity for further ASD research, while also providing a valid screening tool for clinicians. Data from Georgia will add to the growing understanding of the broader ASD phenotype.

Parent-Reported Suicidal Ideation in Three Population-Based Samples of School-Aged Korean Children With Autism Spectrum Disorder and Autism Spectrum Screening Questionnaire Screen Positivity

OBJECTIVES

Higher prevalence of suicidality has been reported in individuals with ASD. This study aimed to (1) Estimate the prevalence of suicidal ideation (SI) in epidemiologically-ascertained, population-based, samples of children with ASD or Autism Spectrum Screening Questionnaire (ASSQ) Screen Positivity (ASP); (2) Determine whether ASD/ASP is an independent risk factor for SI, controlling for known SI risk factors; and, (3) Develop an explanatory model for SI in children with ASD/ASP.

METHODS

Participants came from three epidemiologically-ascertained samples of school-aged Korean children (n = 14,423; 3,702; 4,837). ASSQ ≥ 14 was the cutoff for ASP. A subsample (n = 86) was confirmed to have ASD. SI was based on parents' endorsement of items on the Behavioral Assessment System for Children-2-Parent Report Scale-Children. Logistic regressions were used to assess associations between SI and ASD/ASP, controlling for demographics, peer victimization, behavior problems, and depression. To develop an explanatory model for SI within ASD/ASP, the associations between SI and child characteristics (comorbid conditions, ASD symptoms, IQ, adaptive function) were tested.

RESULTS

SI was higher in children with ASD (14%) and ASP (16.6-27.4%) than ASSQ Screen Negative (ASN) peers (3.4-6.9%). ASD/ASP was strongly predictive of SI (ORs: 2.87-5.67), after controlling for known SI risk factors compared to ASN. Within the ASD and ASP groups, anxiety was the strongest predictor of SI.

CONCLUSIONS

SI prevalence was higher in non-clinical samples of children with ASD and ASP, relative to ASN peers. These results underscore the need for routine screening for SI in children with ASD and social difficulties, particularly those with high anxiety. HighlightsPopulation-based, epidemiologically-ascertained, school-aged childrenASD and ASP are independent risk factors for SI in school-aged childrenAnxiety is an independent risk factor for SI in children with ASD or ASP.

Intoxication and pitch control in tonal and non-tonal language speakers

Alcohol intoxication is known to affect pitch variability in non-tonal languages. In this study, intoxication's effects on pitch were examined in tonal and non-tonal language speakers, in both their native language (L1; German, Korean, Mandarin) and nonnative language (L2; English). Intoxication significantly increased pitch variability in the German group (in L1 and L2), but not in the Korean or Mandarin groups (in L1 or L2), although there were individual differences. These results support the view that pitch control is related to the functional load of pitch and is an aspect of speech production that can be advantageously transferred across languages, overriding the expected effects of alcohol.

Child mortality of twins and singletons among late preterm and term birth: a study of national linked birth and under-five mortality data of Korea

Twins involve a higher risk of perinatal complications compared to singletons. We compared the risk of under five mortality between twins and singletons among late preterm and term births. The national birth data of South Korea pertaining to the years 2010-2014 linked with the mortality record of children aged under 5 years in 2010-2019 was analyzed. The final study population was 2,199,632 singletons and 62,351 twins. We conducted a survival analysis of under-five mortality with adjustment for neonatal and familial factors. Overall under-five mortality rates during the study period were 3.6 and 2.0 for twins and singletons, respectively. Although the unadjusted overall under-five mortality was higher in twins (hazard ratio [HR] = 1.80, 95% confidence interval [CI]: 1.57, 2.06, overall risk), twin birth was associated with comparable or lower risk (HR = 0.70, 95% CI: 0.58, 0.85, overall; 0.70, 95% CI: 0.56, 0.87, excluding neonatal mortality; 0.59, 95% CI: 0.40, 0.86, excluding infant mortality) after controlling for both neonatal and familial factors. Twins born at a gestational age of 34-35 weeks showed a generally lower risk of under-five mortality than their singleton counterparts, regardless of model specification.Conclusion: Among late preterm and term birth, under-5-year mortalities for twins were lower than singleton births when adjusted for neonatal and familial risk factors. This highlights the differential implication of gestational age at birth between twin and singleton in the child mortality.

Response After Repeated Ketamine Injections in a Rat Model of Neuropathic Pain

Ketamine, an N-methyl-D-aspartate antagonist, reduces pain by decreasing central sensitization and pain windup. However, chronic ketamine use can cause tolerance, dependency, impaired consciousness, urinary symptoms, and abdominal pain. This study aimed to investigate the effects of repeated ketamine injections and ketamine readministration after discontinuation in a rat model of neuropathic pain. To induce neuropathic pain, partial sciatic nerve ligation (PSNL) was performed in 15 male Wistar rats, and these animals were divided into three groups: PSNL (control), PSNL + ketamine 5 mg/kg (K5), and PSNL + ketamine 10 mg/kg (K10; n=5 each). Ketamine was injected intraperitoneally daily for 4 weeks, discontinued for 2 weeks, and then readministered for 1 week. Following PSNL, the mechanical withdrawal threshold was determined weekly using the Von Frey. The K10 group showed a significant increase in the mechanical withdrawal threshold, presented here as the target force (in g), at 21 and 28 days compared to the time point before ketamine injection (mean±SE, 276.0±24.0 vs. 21.6±2.7 and 300.0±0.0 vs. 21.6±2.7, respectively; P<0.01) and at 14, 21, and 28 days compared to the control group (108.2±51.2 vs. 2.7±1.3, 276.0±24.0 vs. 2.5±1.5, and 300.0±0.0 vs. 4.0±0.0, respectively; P<0.05). However, in the K10 group, the ketamine effects decreased significantly at 7 days after readministration compared to those after 28 days of repeated injections (P<0.05). In the K10 group, repeated ketamine injections showed a significant increase in antinociceptive effect for >2 weeks, but this ketamine effect decreased after drug readministration.

P–205 Epothilone D as an actin cytoskeleton stabilizer improved mitochondria bioenergenesis and blastocyst formation of mouse preimplantation embryo

Study question

What is primary factor of bioenergetics product activity between microtubule instability and the functional activity of mitochondria in embryo?

Summary answer

The actin cytoskeleton instability is presumably the primary cause for the bioenergenesis of mitochondrial function to the preimplantation embryo development.

What is known already

Mitochondria are cellular organelles dynamically moving and morphological changes. It provides for homeostatic energy to the cell. The dynamic property of the mitochondria is associated with the microtubule network in the cell. However, the stability of the microtubule was clearly identified for preimplantation embryo development.

Study design, size, duration

This study is designed to assess the ATP productivity of the mitochondria, and specifically to observe what its primary factor is in terms of providing microtubule stability in mammalian cells. Additionally, we investigated the relationship between blastocyst formation and actin cytoskeleton stabilization by EpD with 2-cell mice.

Participants/materials, setting, methods

We prepared the microtubule stability regulation model with the HEK293 cell line by using the microtubule stabilizer as an Epothilone D (EpD). Then we analyzed the metabolic activity of the cells through oxidative phosphorylation (OXP) ratios analysis. Also, we performed confocal live imaging to observe mitochondria morphology depending on the cells’ microtubule. Next, we treated EpD to 2-cell culture media for the analysis of blastocyst development ratios.

Main results and the role of chance

EpD significantly increased fusion form. Also, EpD enhance bioenergy ratios like OXP in the mitochondria and functional activity related marker, like mTOR compared with the control. These results suggest that microtubule stabilization enhances mitochondrial metabolism by increasing oxygen consumption. Also, EpD in 2-cell culture media led to a significant increase in the speed of development and 50% higher hatched out blastocyst formation ratios compared to the control group.

Limitations, reasons for caution

This study had limited animal experiments. For the next study, we are planning with an aim to improve the quality and development ratios of human embryos by EpD.

Wider implications of the findings: Microtubule stabilizer has a possibility to recover the mitochondria’s functional activity in the preimplantation embryo development. Mitochondrial functional activity along the actin cytoskeleton may play a pivotal role in determining the embryo quality and development ratios for archive pregnancy.

Trial registration number

non-clinical trials

P–657 Prostaglandin D2 is correlated with follicles development and a reliable marker of ovarian reserve of poor ovarian responder patients

Study question

Is the prostaglandin D2 (PGD2) associated with growing follicles and ovarian reserve of poor ovarian responders?

Summary answer

PGD2 is correlated with ovarian stimulation activity and follicle growth. Especially, poor ovarian responders show a significant decrease in the level of follicular fluid.

What is known already

Prostaglandins (PGs) are involved in the female reproductive process, mainly ovulation, fertilization, and implantation.

Study design, size, duration

We investigated the PGD2 level in the follicular fluid of poor ovarian responders. The collection of human follicular fluid was approved by the Institutional Research and Ethical Committees of CHA University (approval number: 1044308–201611-BR–027–04) from January to December 2019. Follicular fluid was collected from patients with normal ovarian response and patients with POR.

Participants/materials, setting, methods

We studied whether prostaglandin has related to POR in the clinical key factor by measuring human follicular fluid. Follicular fluid was collected from patients with normal ovarian response and patients with POR. The concentration of PGD2 in follicular fluid was determined with ELISA kits following the manufacturer’s protocol.

Main results and the role of chance

We analyzed the level of PGD2 in the follicular fluid of patients with normal ovarian response and patients with POR using an ELISA. The PGD2 concentration was significantly lower in the follicular fluid of patients with POR than in the follicular fluid of young and old patients with normal ovarian response.

Limitations, reasons for caution

This study has an identification of biomarker of the clinical samples as POR criteria patients. Therefore, further investigations aimed at specific recovery of low PGD2 metabolic activity in the CCs during control ovarian stimulation.

Wider implications of the findings: Until now there is no specific biomarker of POR. AMH is just an ovary reserve marker for an indication of ovary function. PGD2 is one of the metabolites in steroid metabolism in the ovary. Therefore, we can find some cure through further study for improved PGD2 production to POR patients.

Trial registration number

none

P–658 Lovastatin promotes the expression of LDL receptor and enhances E2 production in the cumulus cells

Study question

Lovastatin enhanced E2 productive ratios in the cumulus cells through promoted expression of Low-density lipoprotein receptor (LDLR).

Summary answer

Lovastatin up-regulated gene expression of LDLR in the CCs. And the high expression of LDLR promoted E2 productive ratios from CCs.

What is known already

We already reported that the up-regulation of LDLR correlated with clinical pregnancy. Therefore, we found lovastatin as an up-regulator of LDLR expression of clinical pregnancy.

Study design, size, duration

This is an expended study of LDLR to enhance steroidogenesis regarding the effect of lovastatin in the CCs. The collection of human cumulus cells was approved by the Institutional Research and Ethical Committees of CHA University (approval number: 1044308–201611-BR–027–04) from January to December 2019. The CCs were collected from 12 patients with normal ovarian response after oocyte denudation for ICSI.

Participants/materials, setting, methods

We studied whether lovastatin has up-regulated LDLR expression in human CCs. Cumulus cells were collected from patients with young (∼ 36) and old aged patients (37 ∼). After culturing human CCs, they were treated lovastatin for one day. The concentration of E2 in culture medium was measured using Chemiluminescence immunoassay. The mRNA isolated from CCs was analyzed gene expression level through real time-PCR.

Main results and the role of chance

The concentration of E2 was significantly increased in the culture medium treated with lovastatin. The CCs treated with lovastatin increased the expression of LDLR and StAR which are components of the steroidogenesis pathway.

Limitations, reasons for caution

We have found that the role of lovastatin promotes the E2 production by increasing the ldlr gene of CCs. Therefore, further investigations aimed at lovastatin effect on human oocytes embryo whether enhanced quality of oocytes or not.

Wider implications of the findings: Previous data show that high activation of LDLR and StAR was associated with embryo quality and clinical pregnancy in infertile women. Our data suggest that lovastatin is stimulated LDLR expression to enhanced pregnancy ratios of IVF patients.

Trial registration number

none

Effect of the stellate ganglion block on symptoms of ulcerative colitis: A case report

RATIONALE

Chronic ulcerative colitis is an autoimmune disease in which epithelial injury continuously occurs in the colonic mucosa. While mesalazine (5-aminosalicylic acid) is used to treat ulcerative colitis, it can also cause liver failure, headaches, and abdominal pain; therefore, an alternative treatment is required. The purpose of this study was to evaluate the effectiveness of 80 stellate ganglion blocks in reducing pain and other symptoms in a patient with chronic ulcerative colitis.

PATIENT CONCERNS

A 54-year-old female patient with a history of ulcerative colitis was concerned with worsening symptoms, such as abdominal discomfort and bloody-mucous stools, over the past 3 years.

DIAGNOSES

Oozing mucosal bleeding and a small amount of exudate were observed on colonoscopy; a diagnosis of ulcerative colitis was made upon histologic examination.

INTERVENTIONS AND OUTCOMES

A total of 80 stellate ganglion blocks were administered, after which the patient's symptom and pain level was decreased from 6 to 4 points on the numeric rating scale (11-point, 0 = no pain, 10 = worst pain imaginable). Improved clinical signs were observed on colonoscopy at a follow-up assessment.

LESSONS

The stellate ganglion block may be effective for the reduction of pain and other symptoms in patients with chronic ulcerative colitis.

Diagnostic test accuracy of 18F-FDG PET/CT for prediction of programmed death ligand 1 (PD-L1) expression in solid tumours: a meta-analysis

AIM

To investigate the predictive value of integrated 2-[¹⁸F]-fluoro-2-deoxy-d-glucose (¹⁸F-FDG) positron-emission tomography/computed tomography (PET/CT) for the prediction of programmed death ligand 1 (PD-L1) expression in solid tumours via a systematic review and meta-analysis.

MATERIALS AND METHODS

The PubMed, Cochrane, and EMBASE databases, from the earliest available date of indexing through 31 October 2020, were searched for studies evaluating the diagnostic performance of ¹⁸F-FDG PET/CT for prediction of PD-L1 expression in solid tumours other than lung cancer.

RESULTS

Across seven studies (473 patients), the pooled sensitivity for ¹⁸F-FDG PET/CT was 0.75 (95% confidence interval [CI]: 0.65-0.82) without heterogeneity (I² = 47.2, p=0.08) and a pooled specificity of 0.73 (95% CI: 0.64-0.81) with heterogeneity (I² = 53.8, p=0.04). Likelihood ratio (LR) syntheses gave an overall positive likelihood ratio (LR+) of 2.8 (95% CI: 2.1-3.7) and negative likelihood ratio (LR-) of 0.35 (95% CI: 0.26-0.47). The pooled diagnostic odds ratio (DOR) was 8 (95% CI: 5-13). Hierarchical summary receiver operating characteristic (ROC) curve and indicates that the area under the curve was 0.80 (95% CI: 0.77-0.84).

CONCLUSION

The current meta-analysis showed a moderate sensitivity and specificity of ¹⁸F-FDG PET/CT for the prediction of PD-L1 expression in solid tumours. At present, the literature regarding the use of ¹⁸F-FDG PET/CT for the prediction of PD-L1 expression in solid tumours still limited; thus, further large multicentre studies would be necessary to substantiate the diagnostic accuracy of ¹⁸F-FDG PET/CT for prediction of PD-L1 expression in solid tumours.

Prenatal exposure to paternal smoking and likelihood for autism spectrum disorder

LAY ABSTRACT

What is Already Known about This Subject: Genetics, (including de novo mutations), environmental factors (including toxic exposures), and their interactions impact autism spectrum disorder etiology. Paternal smoking is a candidate risk for autism spectrum disorder due to biological plausibility, high prevalence, and potential intervention.What This Study Adds: This original study and its replication confirms that paternal factors can substantially contribute to autism spectrum disorder risk for their offspring. It specifically indicates that paternal smoking both before and during pregnancy contributes significantly to autism spectrum disorder risk.Implications for practice, research, or policy: Smoking prevention, especially in pregnancy planning, may decrease autism spectrum disorder risk in offspring.

[Identification of the side population associated with ATP-binding cassette transporters activity using imaging flow cytometry]

DyeCycle Violet efflux, caused by ATP-binding cassette transporters activity, was analyzed in human colorectal adenocarcinoma cell lines SW480, HT-29, Caco-2 by neans of FACSAria III flow cytometer and ImageStreamX Mk II imaging flow cytometer. Along with similarity of cytometry data obtained on the two instruments, the use of imaging flow cytometry made it possible to characterize the morphology of side population cells, as well as morphology of other cell populations differing in the degree of dye accumulation. The population of cells, which are smaller than the side population cells and practically do not take the dye, is of the special interest. Probably, this population may contribute to the tumor resistance to chemotherapy.

Subepithelial neutrophil infiltration as a predictor of the surgical outcome of chronic rhinosinusitis with nasal polyps

BACKGROUND

Neutrophils present as major inflammatory cells in refractory chronic rhinosinusitis with nasal polyps (CRSwNP), regardless of the endotype. However, their role in the pathophysiology of CRSwNP remains poorly understood. We investigated factors predicting the surgical outcomes of CRSwNP patients with focus on neutrophilic localization.

METHODS

We employed machine-learning methods such as the decision tree and random forest models to predict the surgical outcomes of CRSwNP. Immunofluorescence analysis was conducted to detect human neutrophil elastase (HNE), Bcl-2, and Ki-67 in NP tissues. We counted the immunofluorescence-positive cells and divided them into three groups based on the infiltrated area, namely, epithelial, subepithelial, and perivascular groups.

RESULTS

On machine learning, the decision tree algorithm demonstrated that the number of subepithelial HNE-positive cells, Lund-Mackay (LM) scores, and endotype (eosinophilic or non-eosinophilic) were the most important predictors of surgical outcomes in CRSwNP patients. Additionally, the random forest algorithm showed that, after ranking the mean decrease in the Gini index or the accuracy of each factor, the top three ranking factors associated with surgical outcomes were the LM score, age, and number of subepithelial HNE-positive cells. In terms of cellular proliferation, immunofluorescence analysis revealed that Ki-67/HNE-double positive and Bcl-2/HNE-double positive cells were significantly increased in the subepithelial area in refractory CRSwNP.

CONCLUSION

Our machine-learning approach and immunofluorescence analysis demonstrated that subepithelial neutrophils in NP tissues had a high expression of Ki-67 and could serve as a cellular biomarker for predicting surgical outcomes in CRSwNP patients.

A compact and stable incidence-plane-rotating second harmonics detector

We describe a compact and stable setup for detecting the optical second harmonics, in which the incident plane rotates with respect to the sample. The setup is composed of rotating Fresnel rhomb optics and a femtosecond ytterbium-doped fiber laser source operating at the repetition frequency of 10 MHz. The setup including the laser source occupies an area of 1 m² and is stable so that the intensity fluctuation of the laser harmonics can be less than 0.2% for 4 h. We present the isotropic harmonic signal of a gold mirror of 0.5 pW and demonstrate the integrity and sensitivity of the setup. We also show the polarization-dependent six-fold pattern of the harmonics of a few-layer WSe₂, from which we infer the degree of local-field effects. Finally, we describe the extensibility of the setup to investigate the samples in various conditions such as cryogenic, strained, ultrafast non-equilibrium, and high magnetic fields.

Multi-chord IR-visible two-color interferometer on KSTAR

Major parts of an IR-visible two-color interferometer (TCI) on KSTAR have been upgraded for the multi-chord operation: (1) a diode-pumped-solid-state (DPSS) laser (660 nm) replacing the former HeNe laser (633 nm), (2) vacuum-compatible vibration isolator with titanium retro-reflectors, and (3) full digital phase comparator for multi-chord real-time density signals. The commercial compact DPSS laser suits the multiple chord configuration with its strong beam power (500 mW) and long coherent length (>100 m). Ti retro-reflectors are mounted on vacuum-compatible vibration isolators. The isolators are essential for the visible beams to avoid any fringe skips due to their short wavelength, considering the speed of the mechanical vibration (up to hundreds of μm). Field-programmable-gate-array (FPGA) modules count the entire fringes fast enough with a signal output rate up to 1.25 MHz, solving the fringe skip issues. The FPGA module enables the full digital processing of the phase comparator with a CORDIC algorithm after the sampling rate of 160 MS/s for the 40 MHz intermediate frequency of each beam. The full digital signals are transferred to the main plasma control system in real-time. Stable single-input-single-output operation of the KSTAR density control was demonstrated with the TCI. The real-time density profile control is also promising in the near future, with multiple actuators such as pellets and gas puffings.

Progress of x-ray imaging crystal spectrometer utilizing double crystal assembly on KSTAR

The x-ray imaging crystal spectrometer (XICS) for Korea Superconducting Tokamak Advanced Research (KSTAR) has been upgraded to increase its performance including measurement capabilities and stable operation. A dual crystal assembly for simultaneous measurements of the helium-like and hydrogen-like Ar spectra is successfully installed for improving measurement capabilities. Using a safety viewing port with an illuminator and removing the XICS control system from the harsh KSTAR tokamak hall for a stable operation are newly performed. The experimental results from the improved XICS are investigated.

Sex differences in scores on standardized measures of autism symptoms: a multisite integrative data analysis

BACKGROUND

Concerns have been raised that scores on standard measures of autism spectrum disorder (ASD) symptoms may differ as a function of sex. However, these findings are hindered by small female samples studied thus far. The current study evaluated if, after accounting for age, IQ, and language level, sex affects ASD severity estimates from diagnostic measures among children with ASD.

METHODS

Data were obtained from eight sources comprising 27 sites. Linear mixed-effects models, including a random effect for site, were fit for 10 outcomes (Autism Diagnostic Observation Schedule [ADOS] domain-level calibrated severity scores, Autism Diagnostic Interview-Revised [ADI-R] raw scores by age-based algorithm, and raw scores from the two indices on the Social Responsiveness Scale [SRS]). Sex was added to the models after controlling for age, NVIQ, and an indicator for language level.

RESULTS

Sex significantly improved model fit for half of the outcomes, but least square mean differences were generally negligible (effect sizes [ES] < 0.20), increasing to small to moderate in adolescence (ES < 0.40). Boys received more severe RRB scores than girls on both the ADOS and ADI-R (age 4 + algorithm), and girls received more severe scores than boys on both SRS indices, which emerged in adolescence.

CONCLUSIONS

This study combined several available databases to create the largest sample of girls with ASD diagnoses. We found minimal differences due to sex beyond other known influences on ASD severity indicators. This may suggest that, among children who ultimately receive a clinical ASD diagnosis, severity estimates do not systematically differ to such an extent that sex-specific scoring procedures would be necessary. However, given the limitations inherent in clinically ascertained samples, future research must address questions about systematic sex differences among children or adults who do not receive clinical diagnoses of ASD. Moreover, while the current study helps resolve questions about widely used diagnostic instruments, we could not address sex differences in phenotypic aspects outside of these scores.

Effects of Particulate Matter in a Mouse Model of Oxazolone-Induced Atopic Dermatitis

BACKGROUND

Recent epidemiological studies have demonstrated that air pollution is associated with the inflammatory response and may aggravate inflammatory skin diseases such as atopic dermatitis (AD). However, it is unclear whether particulate matter (PM) aggravates AD symptoms.

OBJECTIVE

The aim of this study was to investigate whether PM exposure affects the skin barrier dysfunction and aggravates AD symptoms using human keratinocytes (HaCaT) cells and a mouse model of oxazolone-induced AD-like skin.

METHODS

Standard reference material (SRM) 1649b, which mainly comprises polycyclic aromatic hydrocarbons, was used as the reference PM. HaCaT cells and mouse model of oxazolone-induced AD-like skin were treated with PM. The mRNA or protein expression levels of stratum corneum (SC) and tight junction (TJ) proteins, inflammatory cytokines, as well as clinical and histological changes of the AD-like skin of mouse model were evaluated. The expression of genes and proteins was analyzed by real-time polymerase chain reaction and Western blotting. Levels of inflammatory cytokines were measured by enzyme-linked immunosorbent assay.

RESULTS

The results revealed that PM downregulates the expression levels of several SC and TJ-related proteins in the mouse model with AD-like skin. Clinically, epidermal and dermal thickness was significantly increased and dermal inflammation was prominent in PM treated AD-like skin.

CONCLUSION

In conclusion, we found that PM aggravates skin barrier dysfunction, clinically augmenting epidermal and dermal thickening with dermal inflammation in AD-like skin. These results suggest that PM may trigger the exacerbation of AD symptoms via skin barrier dysfunction-related mechanisms.

Prevalence of and Factors Associated with School Bullying in Students with Autism Spectrum Disorder: A Cross-Cultural Meta-Analysis

Through this meta-analysis, we sought to examine the prevalence of, risks for, and factors associated with bullying involvement (victimization, perpetration, perpetration-victimization) among students with autism spectrum disorder (ASD). Additionally, we attempted to examine sources of variance in the prevalence and effect sizes of bullying in students with ASD across studies. Systematic database and literature review identified 34 relevant studies (31 for Western countries, three for Eastern countries). Pooled prevalence estimates for victimization, perpetration, and perpetration-victimization in general were 67%, 29%, and 14%, respectively. The risk of victimization in students with ASD was significantly higher than that in typically developing students and students with other disabilities. Further, deficits in social interaction and communication, externalizing symptoms, internalizing symptoms, and integrated inclusive school settings were related to higher victimization, and externalizing symptoms were related to higher perpetration. Finally, moderation analyses revealed significant variations in the pooled prevalences thereof depending on culture, age, school settings, and methodological quality and in the pooled effect sizes according to publication year and methodological quality. Our results highlight needs for bullying intervention for students with ASD, especially those who are younger, are in an inclusive school setting, and have higher social difficulties and externalizing/internalizing symptoms; for intensive research of bullying experiences among students with ASD in Eastern countries; and for efforts to improve the methodological quality of such research.

Identifying the Medical Lethality of Suicide Attempts Using Network Analysis and Deep Learning: Nationwide Study

BACKGROUND

Suicide is one of the leading causes of death among young and middle-aged people. However, little is understood about the behaviors leading up to actual suicide attempts and whether these behaviors are specific to the nature of suicide attempts.

OBJECTIVE

The goal of this study was to examine the clusters of behaviors antecedent to suicide attempts to determine if they could be used to assess the potential lethality of the attempt. To accomplish this goal, we developed a deep learning model using the relationships among behaviors antecedent to suicide attempts and the attempts themselves.

METHODS

This study used data from the Korea National Suicide Survey. We identified 1112 individuals who attempted suicide and completed a psychiatric evaluation in the emergency room. The 15-item Beck Suicide Intent Scale (SIS) was used for assessing antecedent behaviors, and the medical outcomes of the suicide attempts were measured by assessing lethality with the Columbia Suicide Severity Rating Scale (C-SSRS; lethal suicide attempt >3 and nonlethal attempt ≤3).

RESULTS

Using scores from the SIS, individuals who had lethal and nonlethal attempts comprised two different network nodes with the edges representing the relationships among nodes. Among the antecedent behaviors, the conception of a method's lethality predicted suicidal behaviors with severe medical outcomes. The vectorized relationship values among the elements of antecedent behaviors in our deep learning model (E-GONet) increased performances, such as F1 and area under the precision-recall gain curve (AUPRG), for identifying lethal attempts (up to 3% for F1 and 32% for AUPRG), as compared with other models (mean F1: 0.81 for E-GONet, 0.78 for linear regression, and 0.80 for random forest; mean AUPRG: 0.73 for E-GONet, 0.41 for linear regression, and 0.69 for random forest).

CONCLUSIONS

The relationships among behaviors antecedent to suicide attempts can be used to understand the suicidal intent of individuals and help identify the lethality of potential suicide attempts. Such a model may be useful in prioritizing cases for preventive intervention.

Vapor-Phase Passivation of Chlorine-Terminated Ge(100) Using Self-Assembled Monolayers of Hexanethiol

Continued scaling of electronic devices shows the need to incorporate high mobility alternatives to silicon, the cornerstone of the semiconductor industry, into modern field effect transistor (FET) devices. Germanium is well-poised to serve as the channel material in FET devices as it boasts an electron and hole mobility more than twice and four times that of Si, respectively. However, its unstable native oxide makes its passivation a crucial step toward its potential integration into future FETs. The International Roadmap for Devices and Systems (IRDS) predicts continued aggressive scaling not only of the device size but also of the pitch in nanowire arrays. The development of a vapor-phase chemical passivation technique will be required to prevent the collapse of these structures that can occur because of the surface tension and capillary forces that are experienced when tight-pitched nanowire arrays are processed via liquid-phase chemistry. Reported here is a vapor-phase process using hexanethiol for the passivation of planar Ge(100) substrates. Results benchmarking it against its well-established liquid-phase equivalent are also presented. X-ray photoelectron spectroscopy was used to monitor the effectiveness of the developed vapor-phase protocol, where the presence of oxide was monitored at 0, 24, and 168 h. Water contact angle measurements compliment these results by demonstrating an increase in hydrophobicity of the passivated substrates. Atomic force microscopy monitored the surface topology before and after processing to ensure the process does not cause roughening of the surface, which is critical to demonstrate suitability for nanostructures. It is shown that the 200 min vapor-phase passivation procedure generates stable, passivated surfaces with less roughness than the liquid-phase counterpart.

Prevalence and cumulative incidence of autism spectrum disorders and the patterns of co-occurring neurodevelopmental disorders in a total population sample of 5-year-old children

Backgrounds

Whether there is a true increase in autism spectrum disorder (ASD) frequency or not remains unclear. Additionally, the rates of co-existing neurodevelopmental disorders (NDD) in a total population sample has not been fully examined before. Therefore, using a total population sample in Japan, we aimed to estimate the prevalence and cumulative incidence of autism spectrum disorder (ASD) annually, to determine whether there is a true increase in ASD prevalence by estimating the cumulative incidence of ASD annually, and to examine the rates of co-existing neurodevelopmental disorders (NDD).

Method

In this cross-sectional sequential design study, all 5-year-old children in the catchment area underwent the screening annually from the year 2013–2016. Screen-positive children were invited to participate in a comprehensive assessment, including child and parent interview, behavioral observation, and cognitive and motor function testing. All cases were reviewed by a multidisciplinary research team.

Results

Caregivers of 3954 children returned the screening, among which 559 children underwent the assessment with 87 children receiving an ASD diagnosis. Adjusted ASD prevalence was 3.22% (95% confidence interval (CI) 2.66–3.76%). The male to female ratio of the crude prevalence was 2.2:1. The cumulative incidence of ASD up to 5 years of age for the total study years was 1.31% (95% CI 1.00–1.62%). A generalized linear model revealed no significant linear trends in 5-year cumulative incidence over the study years. Only 11.5% of children had ASD alone; the remaining 88.5% were found to have at least one co-existing NDD.

Limitations

Modest sample size for a total population study.

Conclusions

Our findings demonstrate the stability of the 5-year cumulative incidence of ASD, implying no true rise in ASD incident cases over the 4-year study period in the study catchment area. High rates of co-existing NDDs reflect the importance of investigating broad developmental challenges in children with ASD.

Intrinsic and tunable ferromagnetism in Bi0.5Na0.5TiO3 through CaFeO3-δ modification

New (1-x)Bi_0.5Na_0.5TiO₃ + xCaFeO_3-δ solid solution compounds were fabricated using a sol–gel method. The CaFeO_3-δ materials were mixed into host Bi_0.5Na_0.5TiO₃ materials to form a solid solution that exhibited similar crystal symmetry to those of Bi_0.5Na_0.5TiO₃ phases. The random distribution of Ca and Fe cations in the Bi_0.5Na_0.5TiO₃ crystals resulted in a distorted structure. The optical band gaps decreased from 3.11 eV for the pure Bi_0.5Na_0.5TiO₃ samples to 2.34 eV for the 9 mol% CaFeO_3-δ-modified Bi_0.5Na_0.5TiO₃ samples. Moreover, the Bi_0.5Na_0.5TiO₃ samples exhibited weak photoluminescence because of the intrinsic defects and suppressed photoluminescence with increasing CaFeO_3-δ concentration. Experimental and theoretical studies via density functional theory calculations showed that pure Bi_0.5Na_0.5TiO₃ exhibited intrinsic ferromagnetism, which is associated with the possible presence of Bi, Na, and Ti vacancies and Ti³⁺-defect states. Further studies showed that such an induced magnetism by intrinsic defects can also be enhanced effectively with CaFeO_3-δ addition. This study provides a basis for understanding the role of secondary phase as a solid solution in Bi_0.5Na_0.5TiO₃ to facilitate the development of lead-free ferroelectric materials.

Combined effects of sous-vide cooking conditions on meat and sensory quality characteristics of chicken breast meat

This study investigated the combined effects of cooking temperature and time on the meat and eating quality characteristics of the sous-vide chicken breast. For the control group, chicken breast samples were cooked in a convection oven until the internal temperature reached 71°C. Each sample for sous-vide cooking was vacuum packaged and then cooked under continuous thermocontrolled conditions in a water bath at 6 combinations of cooking temperature (60 and 70°C) and time (1, 2, and 3 h). Sous-vide cooked chicken meat at 60°C for 1 h (SV60-1h) showed lower cooking loss (6.58 vs. 26.5%, P < 0.05), Warner-Bratzler shear force (21.7 vs. 29.1 N, P < 0.05), and hardness (9.40 vs. 17.3 N, P < 0.05) than meat cooked by conventional oven. Similar to the objective tenderness parameters, cooked chicken meat from the SV60 treatments for all cooking times showed higher scores in all the tenderness attributes than the control group (P < 0.05). However, a higher flavor intensity was observed in the SV70-3h and control groups than in the SV60 treatments (P < 0.05). Owing to a lesser developed flavor in chicken meat from the SV60-1h treatment, the SV60-2h and 3h treatments were assigned a higher acceptability rating for overall impression (P < 0.05). Therefore, cooking temperature and time of sous-vide significantly influenced the physicochemical and palatability characteristics of chicken breast. In this study, the optimum conditions for the sous-vide chicken breast are to continuously cook at 60°C for 2 to 3 h to improve sensory quality characteristics without reducing the water-holding capacity.

[Expression of ganglioside GD2 on colorectal adenocarcinoma cells]

Using flow cytometry GD2 ganglioside expression was evaluated both on colorectal adenocarcinoma cell lines and on tumor tissue samples from colorectal cancer patients. The marker was found on EpCAM-positive tumor cells in 6 of 12 patients' samples but not on the HT29 and CaCo-2 cell lines. GD2 expression was not an exceptional feature of cancer stem cells, since its expression level was similar on CD133-positive and CD133-negative tumor cells. Thus, the presence of GD2 ganglioside was revealed on colorectal adenocarcinoma cells for the first time. This finding makes it possible to use targeted therapy to treat this disease.

Transplant outcomes in kidney recipients with lupus nephritis, and systematic review

Background

Despite improved survival of patients with lupus nephritis (LN), some require kidney transplantation because of progression to end-stage renal disease (ESRD). However, the transplant outcomes of these patients and other recipients have not been thoroughly compared.

Methods

In total, 1848 Korean kidney recipients who underwent transplantation from 1998 to 2017 at two tertiary referral centers were evaluated retrospectively. Among them, 28 recipients with LN, and 50 control recipients matched by age, sex, and donor type, were compared with respect to graft and patient survival. We pooled our data with 17 previous cohort studies in which the graft survival of recipients with LN was described in detail.

Results

During the median follow-up period of 9.5 years (maximum 21 years), graft failure (GF) occurred in 10.7% and 16.0% of LN and control recipients, respectively. No differences were found in the rates of GF and death-censored graft failure or patient survival between the two groups. The risks of acute T cell-mediated and antibody-mediated rejection were also similar between the two groups. The pooled analysis showed similar 1- and 5-year graft survival rates between LN and control recipients.

Conclusions

Kidney transplantation is an acceptable option in patients with concurrent LN and ESRD.

Design and validation of a ten nanosecond resolved resistive thermometer for Gaussian laser beam heating

Pulsed laser processing plays a crucial role in additive manufacturing and nanomaterial processing. However, probing the transient temperature field during the pulsed laser interaction with the processed materials is challenging as it requires both high spatial and temporal resolution. Previous transient thermometry studies have measured neither sub-100 µm spatial resolution nor sub-10 ns temporal resolution. The temperature field induced by Gaussian laser beam profiles has also not been accounted for. Here, we demonstrate a 9 ns rise time, 50 µm sized Pt thin-film sensor for probing the temperature field generated by a nanosecond pulsed laser on a semiconductor thin film. The measurement error sources and associated improvements in the thin film fabrication, sensor patterning, and electrical circuitry are discussed. We carried out the first experimental and theoretical analysis of spatial resolution and accuracy for measuring a Gaussian pulse on the serpentine structure. Transparent silica and sapphire substrates, as well as 7-45 nm insulation layer thicknesses, are compared for sensing accuracy and temporal resolution. Finally, the measured absolute temperature magnitude is validated through the laser-induced melting of the 40 nm thick amorphous silicon film. Preliminary study shows its potential application for probing heat conduction among ultrathin films.

Dietary threonine prevented stress-related mucosal diseases in rats

Stress-related mucosal disease (SRMD), or stress ulceration, is a group of conditions ranging from stress-related superficial gastric mucosal damage to deep gastric ulcers that are primarily correlated with mucosal ischemia, and pharmacologic interventions that optimize tissue perfusion or preserve defensive mucus aim to decrease the occurrence of conditions, such as gastric acidity, or enhance gastric defenses. However, the identification of multifactorial pathogenesis may be effective in preventing SMRD, and the use of stress prophylaxis is generally preferred. Since threonine is a component in the polymerization and synthesis of gastric mucin and possibly enhanced defense actions and lignin may provide structural support for defense and antioxidative function, we hypothesized that dietary intake of threonine and/or lignin can enhance defense against SRMD. The water immersion-restraint stress (WIRS) was used in rats and additional groups were pretreated with threonine alone or the combination of threonine and lignin. Based on gross and microscopic evaluations, threonine alone or the combination of threonine and lignin, a natural antioxidant, significantly reduced the development of SRMD (P < 0.05). According to molecular explorations, the levels of inflammatory mediators, such as interleukin (IL)-8, IL-6, IL-1β, inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-α), and interferon gamma (IFN-γ), all of which are mediators that play a significant role in controlling WIRS, significantly decreased in the groups pretreated with either threonine alone or the combination of threonine and lignin (P < 0.01). WIRS significantly increased apoptosis in the stomach. However, the apoptotic index significantly decreased with threonine pretreatment. According to periodic acid Schiff staining results, the expression of gastric mucin was significantly preserved in groups pretreated with threonine but remarkedly decreased in the WIRS group. The gastric heme oxygenase-1 levels significantly increased in the group treated with threonine. In conclusion, the dietary intake of threonine or the combination of threonine and lignin is effective in preventing SRMD.

Effect of the Compounding Conditions of Polyamide 6, Carbon Fiber, and Al2O3 on the Mechanical and Thermal Properties of the Composite Polymer

Among the composite manufacturing methods, injection molding has higher time efficiency and improved processability. The production of composites via injection molding requires a pre-process to mix and pelletize the matrix polymer and reinforcement material. Herein, we studied the effect of extrusion process conditions for making pellets on the mechanical and thermal properties provided by injection molding. Polyamide 6 (PA6) was used as the base, and composites were produced by blending carbon fibers and Al₂O₃ as the filler. To determine the optimum blending ratio, the mechanical properties, thermal conductivity, and melt flow index (MI) were measured at various blending ratios. With this optimum blending ratio, pellets were produced by changing the temperature and RPM conditions, which are major process variables during compounding. Samples were fabricated by applying the same injection conditions, and the mechanical strength, MI values, and thermal properties were measured. The mechanical strength increased slightly as the temperature and RPM increased, and the MI and thermal conductivity also increased. The results of this study can be used as a basis for specifying the conditions of the mixing and compounding process such that the desired mechanical and thermal properties are obtained.

Treatment of latent tuberculous infection among health care workers at a tertiary hospital in Korea

OBJECTIVE

To evaluate the acceptance of, adherence to, and outcomes of latent tuberculous infection (LTBI) treatment among health care workers (HCWs).

DESIGN

This was a retrospective study in a tertiary hospital in Korea. From May to August 2017, 2190 HCWs simultaneously underwent a tuberculin skin test (TST) and interferon-gamma release assay (IGRA). LTBI was diagnosed if the TST induration was 10 mm or IGRA results were positive.

RESULTS

Of 2190 HCWs tested, 1006 (45.9%) were diagnosed with LTBI. Of these, 655 (65.1%) HCWs visited out-patient clinics, 234 (35.7%) of whom were advised treatment by physicians. Among these, 120 (51.3%) accepted the physicians' recommendations. In general, HCWs who were older, male and smoked were less likely to visit out-patient clinics. Sixty (50%) HCWs received 3 months of isoniazid plus rifampicin (3HR) and 57 (47.5%) HCWs received 4 months of rifampicin (4R). The proportion of HCWs with 2 side effects (3HR 20% vs. 4R 7.0%, P = 0.041) and drug stoppage rate (3HR 20% vs. 4R 5.3%, P = 0.017) were higher in the 3HR group than in the 4R group. Of the 120 HCWs, 78 (65%) completed LTBI treatment.

CONCLUSION

Overall, the acceptance and completion rate for LTBI treatment was not adequate. For effective LTBI management in HCWs, further programmatic strategies are needed.