Adjusting for Confounders in Outcome Studies Using the Korea National Health Insurance Claim Database: A Review of Methods and Applications

OBJECTIVES

Adjusting for potential confounders is crucial for producing valuable evidence in outcome studies. Although numerous studies have been published using the Korea National Health Insurance Claim Database, no study has critically reviewed the methods used to adjust for confounders. This study aimed to review these studies and suggest methods and applications to adjust for confounders.

METHODS

We conducted a literature search of electronic databases, including PubMed and Embase, from January 1, 2021 to December 31, 2022. In total, 278 studies were retrieved. Eligibility criteria were published in English and outcome studies. A literature search and article screening were independently performed by 2 authors and finally, 173 of 278 studies were included.

RESULTS

Thirty-nine studies used matching at the study design stage, and 171 adjusted for confounders using regression analysis or propensity scores at the analysis stage. Of these, 125 conducted regression analyses based on the study questions. Propensity score matching was the most common method involving propensity scores. A total of 171 studies included age and/or sex as confounders. Comorbidities and healthcare utilization, including medications and procedures, were used as confounders in 146 and 82 studies, respectively.

CONCLUSIONS

This is the first review to address the methods and applications used to adjust for confounders in recently published studies. Our results indicate that all studies adjusted for confounders with appropriate study designs and statistical methodologies; however, a thorough understanding and careful application of confounding variables are required to avoid erroneous results.

Trends in telemedicine utilization for mental illness during the COVID-19 pandemic: an analysis of a nationwide database in Korea

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic has worsened mental health and reduced access to mental health services. During the pandemic, the demand for telemedicine has increased and related laws have been enacted. This study aimed to investigate telemedicine use for cases of major mental illnesses during the COVID-19 pandemic and to compare the characteristics of patients who received telemedicine service with those of patients who received in-person care.

METHODS

This population-based, cross-sectional, observational study was based on health insurance claims data, and included 2,749,872 patients who received outpatient treatment for mental illness from February 24, 2020 to June 30, 2022. Logistic regression was performed to assess the relationships between patient characteristics and telemedicine service use. Patients who received telemedicine services were analyzed in subgroups of each mental illness.

RESULTS

During the study period, 80,157 patients (2.9%), with an average age of 63 years, received at least one telemedicine treatment. There was a predominance of women and medical aid recipients. The lowest proportion of telemedicine treatments was for depression (2.1%), and the highest was for dementia (6.7%). The proportion of patients receiving telemedicine in long-term care hospitals was high (22.6%), with the highest odds ratio (OR) (5.84), compared with that in tertiary or general hospitals, followed by that in psychiatric hospitals and clinics. The proportions were high in the departments of internal medicine, neurology, and psychiatry. Patients aged > 80 years received most telemedicine treatment (OR: 1.23) across all diagnoses. Cases of dementia and other mental disorders had higher ORs (2.60 and 2.36, respectively) compared with cases of depression. Except for dementia and behavioral/emotional disorders, hospitalization increased the probability of telemedicine treatment. Comorbidities were positively associated with telemedicine treatment.

CONCLUSIONS

Older people and people with other physical illnesses were more likely to use telemedicine treatments temporarily provided during the pandemic. Telemedicine maintained continuity of treatment for patients with dementia and severe mental illnesses. Telemedicine can be useful for filling the medical gaps for vulnerable populations other than those with mild mental illnesses. This aspect should be considered for the future establishment of telemedicine systems.

The Feasibility of Fast, Four-Dimensional Computed Tomography-Based O-Ring Linac Plans for Stereotactic Body Radiotherapy in Patients with Poor Performance Status

PURPOSE/OBJECTIVE(S)

As patients with poor performance status cannot endure long treatment times, it can lead to unplanned and prolonged radiation treatment or discontinuation of treatment. Moreover, prolonged radiation treatment appears to negatively affect survival for patients. We aimed to verify the feasibility of fast 4DCT-based O-ring linear accelerator (LINAC) treatment in lung 4D stereotactic body radiotherapy (SBRT).

MATERIALS/METHODS

This study included data of 38 patients who received lung 4D-SBRT. Gating20-70% plans were based on 4DCT data obtained at phase values ranging from 20-70% using a C-arm LINAC. Non-GatingFB plans were retrospectively established based on 4DCT data obtained at phase values of 0-90% using an O-ring LINAC. The prescribed dose of 4,800 cGy was delivered to PTV in four fractions. The conformity index (CI), homogeneity index (HI), and gradient measurement (GM) of the PTV were analyzed to compare dosimetric data between Gating20-70% and Non-GatingFB plans. Organs at risks (OARs) were analyzed in accordance with the RTOG 0915 protocol. Treatment delivery time and total monitor units (MU) were analyzed to compare the efficiency of treatment delivery. Statistical comparisons were performed using the Wilcoxon signed-rank test (p<0.05).

RESULTS

For the PTV, there was no significant difference in the CI or HI between Gating20-70% and Non-GatingFB plans (CI: 1.337±0.137, 1.335±0.174, HI: 0.939±0.015, 0.939±0.016, all at p>0.05). However, there was a significant difference in GM between Gating20-70% and Non-GatingFB plan (1.528±0.206 cm, 1.381±0.222 cm, p<0.001). For OARs, all plans met the criteria for dose constraint. There was a significant difference between Gating20-70% and Non-GatingFB plans except in the spinal cord. In particular, D1000cc and D1500cc values for the ipsilateral lung for Gating20-70% plans were 31.6% and 59.9% lower than those for Non-GatingFB plans (D1000cc: 50.780±132.061 cGy, 34.755±102.480 cGy, p<0.001, D1500cc: 6.641±14.598 cGy, 2.666±7.926 cGy, p<0.001). Treatment delivery time was 92% longer for Gating20-70% plans than for Non-GatingFB plans (5.0±0.4 min, 9.6±3.3 min, p = 0.043). The total MU value for Gating20-70% plans was 9.6% higher than that for Non-GatingFB plans (3665.8±230.7, 4016±236.9, p = 0.039).

CONCLUSION

When compared to OARs both plans were acceptable per RTOG-0915 protocol, but significant differences were between Non-GatingFB and Gating20-70% plans. However, treatment delivery time of Non-GatingFB plans decreased by 47.9% than Gating20-70% plans. We verified the feasibility of fast 4DCT-based O-ring LINAC treatment for patients who cannot endure long treatment times due to poor performance status in lung 4D-SBRT. In further study, we will analyze dosimetric differences and treatment delivery efficiency considering tumor motion according to tumor location.

Mapping the Anatomical Distribution of MRI-Identified Locoregional Recurrence following Robotic-Assisted Laparoscopic Prostatectomy for Prostate Adenocarcinoma

PURPOSE/OBJECTIVE(S)

The pattern of locoregional recurrence specifically after robotic-assisted laparoscopic prostatectomy (RALP) for prostate adenocarcinoma is still unknown. In this study, we reviewed pelvic magnetic resonance images (MRI) after postoperative biochemical recurrence (BCR) and drew a map of locoregional recurrence to support evidence of determining the optimal target volume of salvage radiotherapy in a post-RALP BCR scenario.

MATERIALS/METHODS

We have retrospectively searched 7,583 prostate adenocarcinoma patients who have received RALP in our institution between January 2010 and December 2021, and found a pool of highly selected patients with gross tumor recurrence confirmed by post-BCR pelvic MRIs and did not have other histories of malignancy. BCR was defined as the serum PSA more or equal to 0.2 ng/mL, or three consecutive increases. Patients with serum PSA nadir more or equal to 0.2 ng/mL on the 90th postoperative day (POD 90) were excluded to guarantee successful tumor removal. We have reviewed serum PSA levels using R codes, MRI and pathological reports using Excel, and descriptive statistics using SPSS 25. The gross lesions were contoured on the correlating MRIs using MIM Maestro 7.1. The RT structure DICOM files were merged into a map using MATLAB 2022b. In addition, we have conducted Fisher exacted test, Mann-Whitney U test, and logistic regression to identify risk factors for regional recurrence.

RESULTS

A total of 173 patients were identified with locoregional recurrence from post-BCR pelvic MRIs, and 139 (80.3%) patients were in the high-risk group or very-high-risk group according to the NCCN guidelines: 57 (32.9%) patients with histological grade group 5, 50 (28.9%) patients with initial PSA over 20 ng/mL, 114 (65.9%) patients with extracapsular extension, 55 (31.8%) patients with seminal vesicle invasion, and 15 (9%) patients with pN1. The median follow-up was 4.7 (IQR 2.8-6.9) years for pelvic MRIs and 5.8 (IQR 4.0-8.6) years for serum PSA. The BCF survival was median of 10.7 (IQR 4.6-19.1) months, and the locoregional recurrence-free survival was median of 24.6 (IQR 9.7-49.4) months for this subgroup of patients. At first locoregional recurrence, 148 (85.5%) patients were local only, 20 (11.6%) patients were regional only, and 5 (2.9%) patients were both local and regional. Out of the 25 patients with regional recurrence, the incidence of gross tumor recurrence differed by nodal sites: 3 (12%) in perirectal space, 5 (20%) in internal iliac, 7 (28%) in obturator, 13 (52%) in external iliac, and 6 (24%) in common iliac lymph nodes.

CONCLUSION

We have found 173 patients and were able to map reliable gross tumor recurrence sites after RALP and confirmed by pelvic MRIs following BCR. The map supports evidence of using the existing consensus pelvic clinical target volume of salvage radiotherapy, in a post-RALP BCR scenario.

Prediction of Lymphopenia and Survival with Baseline Absolute Lymphocyte Count and Irradiated Dose to Immune Cells in Patients with Non-Small Cell Lung Cancer Treated with Concurrent Chemoradiotherapy

PURPOSE/OBJECTIVE(S)

This study aimed to investigate the effect of effective dose to immune cell (EDIC) combined with pre-radiotherapy (RT) absolute lymphocyte count (ALC) on treatment-related lymphopenia during RT and treatment outcome in patients with locally advanced non-small cell lung cancer (NSCLC). A subgroup analysis in patients who received consolidation immunotherapy was also conducted.

MATERIALS/METHODS

Between August 2008 and December 2021, 517 patients with locally advanced NSCLC treated with definitive concurrent chemoradiotherapy (CRT) were retrospectively analyzed. All patients had serial complete-blood-count tests at pre-, and during-CRT. Severe lymphopenia was defined as ALC < 0.5x109cells/L during RT. EDIC was calculated according to mean doses of the lung, heart and the total body. The patients were grouped according to high and low EDIC and pre-RT ALC and was assessed for its correlation with radiation induced lymphopenia and survival outcomes.

RESULTS

Of 517 eligible patients, most of the patients received weekly paclitaxel with carboplatin (90.3%) and 195 patients (37.7%) received consolidation immunotherapy following CRT. A median radiation dose of 63 Gy (IQR, 60-64.5) was delivered in 30 fractions. The optimal cutoff value of EDIC and pre-RT ALC for predicting severe lymphopenia were 2.89 Gy and 2.03x109cells/L, respectively. High risk group was defined as EDIC ≥ 2.89 Gy and pre-RT ALC < 2.03x109cells/L, low risk group as EDIC <2.89 Gy and pre-RT ALC ≥ 2.03x109cells/L, and intermediate group as EDIC ≥ 2.89 Gy and pre-RT ALC ≥ 2.03x109cells/L or EDIC < 2.89 Gy and pre-RT ALC < 2.03x109cells/L. The incidence of severe lymphopenia during RT in high, intermediate, and low risk group was 90.1%, 77.1%, and 52.3%, respectively (p<0.001). The risk groups were independent predictors for both progression-free survival (PFS) (p<0.001) and overall survival (OS) (p<0.001). The high-risk group had higher incidence of locoregional and distant recurrences (p<0.001). In the subset of patients who were treated with consolidation immunotherapy, the risk groups were predictive of severe lymphopenia (p = 0.001), PFS (p = 0.004), and OS (p = 0.012).

CONCLUSION

This study demonstrated that the combination of EDIC and pre-RT ALC is a predictor for severe lymphopenia during RT, recurrence, and survival in patients with locally advanced NSCLC who received CRT. Moreover, the combination of EDIC and pre-RT ALC may serve as a potential biomarker for the benefit of maintenance immunotherapy.

Single-incision robotic colorectal surgery with the da Vinci SP® surgical system: initial results of 50 cases

PURPOSE

The da Vinci SP® (dVSP) surgical system (Intuitive Surgical, Sunnyvale, CA, USA), a robotic platform designed for single-incision surgery, overcame the need for multiple ports in traditional robotic surgery and issues including triangulation and retraction in single-incision laparoscopic surgery. However, previous studies only included case reports or series with small sample sizes. The aim of this study was to assess the safety and performance of the dVSP surgical system and its instruments and accessories for colorectal procedures.

METHODS

The medical records of patients who had surgery with the dVSP from March 2019 to September 2021 at Ewha Womans University Seoul Hospital were investigated. The pathologic and follow-up data of patients who had malignant tumors were analyzed separately to evaluate oncological safety.

RESULTS

Fifty patients (26 male and 24 female) with a median age of 59 years (interquartile range 52.5-63.0 years) were enrolled. The procedures included low anterior resection with total mesorectal excision (n = 16), sigmoid colectomy with complete mesocolic excision and central vessel ligation (CME + CVL) (n = 14), right colectomy with CME + CVL (n = 9), left colectomy with CME + CVL (n = 4), right colectomy (n = 6), and sigmoid colectomy (n = 1). Operative time significantly decreased after 25 cases (early phase vs. late phase; operative time 295.0 min vs. 250.0 min, p = 0.015; docking time 16.0 min vs. 12.0 min, p = 0.001; console time 212.0 min vs. 190.0 min, p = 0.019). Planned procedures were successfully completed in all patients. Postoperative outcomes were acceptable with only six cases of mild adverse events through a 3-month follow-up. No local recurrence and only one case of systemic recurrence occurred within 1 year postoperatively.

CONCLUSIONS

This study demonstrated the surgical and oncological safety and feasibility of dVSP, which may be a novel surgical platform for colorectal surgery.

Metropolitan water purification facilities towards variability mitigation of the renewable resources: Optimal bid method for small hydropower generators

As carbon neutrality in the power system arises as one of the important issues, numerous nations have been increasing penetration of the renewable resources. However, greater penetration of the renewable resources in the power systems has caused reliability issues due to the innate unpredictable output characteristics. For minimization of unpredictability and its consequential effects on the system reliability, the nations such as the Republic of Korea, Great Britain and Australia have been introduced market-based variability mitigating measures. The incentive policy driven market-based measures were designed to draw voluntary participation from the asset owners capable of providing controllability over the resources aggregated to be a single portfolio. Small hydropower generators in metropolitan water purification facilities can be actively utilized for such mitigation because of their relatively stable output characteristics. However, entities responsible for metropolitan water purification facilities with small hydropower generators have been reluctant to participate in the market with the mitigations incentive since there are no structured methods to acquire dispatch reliability of the water resources considering participation in the energy market. Thus, this paper presents a scheduling algorithm for the aggregated portfolio of renewable resources, utilizing small hydropower generators as one of the tools for variability mitigation. In the results, the portfolio-wide forecast error was reduced to below 2% in the presence of the scheduling algorithm and small hydropower generators as mitigation resources, while the water intake schedule at water purification facilities remained evenly distributed. Small hydropower generators played a key role in mitigating variability in the algorithm, and the revenue generated from the participation of these small hydropower generators contributed to approximately one third of the gross revenue from the portfolio. The algorithm was demonstrated to provide renewable resource owners with an additional revenue stream, beyond what is typically provided by government subsidies.

Trends in the Quality of Primary Care and Acute Care in Korea From 2008 to 2020: A Cross-sectional Study

OBJECTIVES

Measuring the quality of care is paramount to inform policies for healthcare services. Nevertheless, little is known about the quality of primary care and acute care provided in Korea. This study investigated trends in the quality of primary care and acute care.

METHODS

Case-fatality rates and avoidable hospitalization rates were used as performance indicators to assess the quality of primary care and acute care. Admission data for the period 2008 to 2020 were extracted from the National Health Insurance Claims Database. Case-fatality rates and avoidable hospitalization rates were standardized by age and sex to adjust for patients' characteristics over time, and significant changes in the rates were identified by joinpoint regression.

RESULTS

The average annual percent change in age-/sex-standardized case-fatality rates for acute myocardial infarction was -2.3% (95% confidence interval, -4.6 to 0.0). For hemorrhagic and ischemic stroke, the age-/sex-standardized case-fatality rates were 21.8% and 5.9%, respectively in 2020; these rates decreased since 2008 (27.1 and 8.7%, respectively). The average annual percent change in age-/sex-standardized avoidable hospitalization rates ranged from -9.4% to -3.0%, with statistically significant changes between 2008 and 2020. In 2020, the avoidable hospitalization rates decreased considerably compared with the 2019 rate because of the coronavirus disease 2019 pandemic.

CONCLUSIONS

The avoidable hospitalization rates and case-fatality rates decreased overall during the past decade, but they were relatively high compared with other countries. Strengthening primary care is an essential requirement to improve patient health outcomes in the rapidly aging Korean population.

Changes in mental health service utilization before and during the COVID-19 pandemic: a nationwide database analysis in Korea

Objectives

The present study examined the impact of the coronavirus disease 2019 (COVID-19) pandemic on mental health service utilization through a comparative analysis of nationwide data regarding inpatient care users, outpatient visits, emergency department (ED) visits, and admissions via the ED before and during the pandemic.

Methods

Data from approximately 350,000 Koreans diagnosed with mental illness were analyzed in terms of hospitalization, outpatient visits, and ED visits between January 2018 and June 2021. An interrupted time series analysis was conducted to determine the significance of changes in mental health service utilization indicators.

Results

The number of hospital admissions per patient decreased by 1.2% at the start of the pandemic and 0.7% afterward. The length of hospital stay increased by 1.8% at the outbreak of the pandemic, and then decreased by 20.2%. Although the number of outpatients increased, the number of outpatient visits per patient decreased; the number of outpatient visits for schizophrenia (3.4%) and bipolar disorder (3.5%) significantly decreased immediately post-outbreak. The number of ED visits per patient decreased both immediately post-outbreak and afterward, and ED visits for schizophrenia (19.2%), bipolar disorder (22.3%), and depression (17.4%) decreased significantly immediately post-outbreak. Admissions via the ED did not show a significant change immediately post-outbreak.

Conclusion

Mental health service utilization increased during the pandemic, but medical service use decreased overall, with a particularly significant decrease in ED utilization. As the pandemic worsened, the decline in outpatient visits became more pronounced among those with severe mental illness.

Supplementation with rumen-inert fat in the growing phase altered adipogenic gene expression and the size and number of adipocytes in Hanwoo steers

We hypothesized that the provision of rumen-inert fat (RIF) to growing cattle (9 to 13 mo of age) would affect the expression of genes involved in lipid metabolism and thereby affect the size and number of adipocytes of steers slaughtered at 30 mo of age. Thirty steers with an average initial body weight (BW) of 239 ± 25 kg were allocated to six pens, balanced for BW and genetic merit for marbling, and assigned to one of two treatment groups: control (only basal diet) or test diet (basal diet with 200 g of RIF per day, on an as-fed basis) for 5 mo. Biopsy samples of longissimus lumborum (LM) muscle were then collected for analysis of fatty acid composition and gene expression. Both groups were then fed the same basal diets during the early and late fattening phases, without RIF, until slaughter (average shrunk BW = 759 kg). Supplementation with RIF increased the longissimus thoracis (LT) intramuscular fatty acid concentration at slaughter (P = 0.087) and numerically increased the quality grade score (P = 0.106). The LM intramuscular relative mRNA expression of genes such as PPARα, ZFP423 and SREBP1, FASN, SCD, FABP4, GPAT1, and DGAT2 were downregulated (P < 0.1) following RIF supplementation. Supplementation of RIF decreased (P < 0.1) diameter and concomitantly increased intramuscular adipocytes per viewing section at slaughter. This likely was caused by promotion of triacylglycerol hydrolysis during the growing phase. Another possible explanation is that the relative mRNA expression of gene ATGL was upregulated by RIF supplementation during the growing (P < 0.1) and the fattening phases (P < 0.05), while the genes associated with fatty acid uptake (FABP4) and esterification (DGAT2) were downregulated during the growing phase and upregulated (P < 0.1) during the fattening phase. This implies that the lipid turnover rate was higher for steers during the growing than fattening phase. This study demonstrated that RIF supplementation during the growing phase induced a carryover effect on the lipogenic transcriptional regulation involved in adipocyte lipid content of intramuscular adipose tissue; increased triacylglycerol hydrolysis during the growing phase subsequently was followed by increased lipid accumulation during the fattening phases.

SGO and the elephant that is still in the room: Wellness, burnout and gynecologic oncology

OBJECTIVE

To measure wellness and burnout among gynecologic oncology clinicians and identify trends and at-risk populations to inform future interventions.

METHODS

Gynecologic oncologist (GO) and advanced practice provider (APP) responses to the 2020 Society of Gynecologic Oncology State of the Society survey were analyzed. The Maslach Burnout Inventory criteria for burnout was used. Work-life balance was scored on a 5-point Likert scale. Chi-square tests were used to compare mental health factors and the prevalence of burnout. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for associations between burnout and gender.

RESULTS

543 survey responses were included for analysis. Most GO (54%) and all APP respondents were female. Female GOs were disproportionately affected by burnout particularly in the Northeast (female(F): 40.9% vs male(M): 19.1%, p = 0.007) and South (F: 42.5% vs M:22.9%, p = 0.01). Burnout in female GOs over 40 was 1.79 (CI: 1.13-2.83; p-value 0.01) times higher than similarly aged males. Females in non-private practice experienced burnout 1.66 times that of males in similar positions (CI: 1.18-2.94; p < 0.0001). Female GOs reported the worst work-life balance across all 5 domains. APPs and female GOs experienced more stress and feeling overwhelmed compared to men. GOs were more reluctant to see a mental health professional (p = 0.0003) or take medication (p = 0.009) than APPs.

CONCLUSIONS

Burnout in gynecologic oncology persists in both genders and is felt most acutely by female GOs. APPs are not immune and would benefit from inclusion in future research to mitigate burnout in healthcare clinicians.

Genetic and clinical characteristics of transthyretin cardiac amyloidosis in Koreans

Background/Introduction

Transthyretin amyloidosis with mutations (aTTRv amyloidosis) have over 100 recognized pathogenic mutations of the TTR gene and its clinical manifestations are very heterogenous. Through the global THAOS (Transthyretin Amyloidosis Outcomes Survey) patient registry, different and several types of mutants and clinical differences have been identified. Awareness of aTTRv amyloidosis is now becoming somewhat significant amongst physicians all over the world. This is a detailed look at such efforts in Korea.

Purpose

We aimed to seek the geologic significance of aTTRv amyloidosis in South Korea.

Methods

This was an analysis of 638 Korean amyloidosis patients in a single center over a period of 16 years from 1995 to October 2021. 95 individuals were found with aTTR mutations.

Results

aTTRv amyloidosis constituted 14.8% (n=95) of amyloidosis patients, and the most commonly involved organ being the heart (61.7%, n=58). Unlike the rest of the world, the mixed phenotype was most common (51.0%, n=48) in Korea and the most universal mutation in Koreans were Asp38Ala, which only constitutes about 1.0% in the THAOS registry. Val30Met mutation, which comprises 76% of the mutation in the THAOS registry, was mostly associated the neurologic phenotypes. However, the same mutations in Korea mixed phenotypes with cardiac (38.4%) and neurologic (37%) symptoms.

Conclusion

aTTRv amyloidosis in Korea is different from other patients worldwide. The mixed phenotype was most common, emphasizing the need for heart failure management in the Korean population. Genotype wise, Koreans held a less common mutation of Asp38Ala. The most common mutation of Val30Met was more likely to be associated cardiac symptoms, which concurs with other studies that suggesting that geological features are more important than mutations itself.

Funding Acknowledgement

Type of funding sources: None.

Efficacy of Nucleoplasty for Radiculopathy Caused by Foraminal Cervical Disc Herniation: Clinical Results of Case Series and Technical Note

BACKGROUND

Percutaneous cervical nucleoplasty (PCN) is a minimally invasive technique used for the treatment of cervical disc herniation. However, if the lesion is located at the neural foramen, complete access and effective neural decompression are often challenging because of the special anatomical condition of the uncovertebral joint, osteophyte, and facet joint of the cervical foraminal space.

OBJECTIVES

To investigate the effect of PCN on radiculopathy caused by foraminal cervical disc herniation (FCDH).

STUDY DESIGN

Retrospective case series.

SETTING

Single-center tertiary hospital.

METHODS

This study included 44 patients with radiculopathy caused by FCDH who were treated with PCN. Visual analog scale (VAS) scores, preoperative, 1 week, and 3 months postoperatively, and at the last follow-up, as well as the Macnab criteria, were used to evaluate clinical outcomes. A paired t-test was used to compare the preoperative and follow-up VAS scores. The percentage of patients with VAS scores &lt;= 3 at each follow-up time point was also investigated. Statistical significance was set at P &lt; 0.05.

RESULTS

Twenty-seven men (62.4%) and 17 women (38.6%) were enrolled in this study. The mean age was 54.5 years (range 31-81). The average follow-up period after the operation was 15.4 months (range 3.7-30.8). The mean preoperative VAS was 7.50 ± 1.21. The VAS scores at 1 week, 3 months, and the last follow-up were 4.36 ± 2.46, 3.20 ± 2.58, and 2.91 ± 2.74, respectively, showing a significant improvement in pain compared to before the operation (P &lt; 0.001 for all). The number of patients (percentage) with a VAS score of &lt;= 3 was 20 (45.5%), 28 (63.6%), and 31 (70.5%) of 44 patients at 1 week, 3 months, and the last follow-up, respectively. The number of patients (percentage) with excellent, good, fair, or poor satisfaction according to the Macnab criteria was 17 (38.6%), 9 (20.5%), 8 (18.2%), and 10 (22.7%) of 44, respectively. No patients experienced postoperative complications.

LIMITATIONS

This study was retrospective and included a small number of patients from a single center.

CONCLUSIONS

Although PCN for radiculopathy caused by FCDH is thought to have limitations because of the surrounding bony structure, the clinical outcome seemed favorable. If PCN is not contraindicated, it may be a viable treatment option for CR due to FCDH.

PSVIII-16 Metagenomic Analyses of Microbial and Carbohydrate-Active Enzymes in the Rumen of Holstein Steers Supplemented with Seeds of Pharbitis nil

Our previous research revealed the effects of dietary supplementation of Pharbitis nil seeds (PA) in improving the ruminal methane reduction and digestibility in Hanwoo steers. The objective of this study was to further investigate the effects of PA supplementation on rumen microbial taxonomy, Kyoto Encyclopedia of Genes and Genomes (KEGG) Orthology functional categories and the diversity of carbohydrate-active enzymes (CAZymes). Five rumen cannulated Holstein steers (744 ± 35 kg) were fed either basal diet (Control) or basal diet supplemented with PA at 5% dry matter intake (PA5) for two consecutive periods of 40 days in pairwise comparison. Rumen fluid was collected on the last day of each period after 4h of morning feeding. Analysis of rumen microbial metagenome revealed that contigs assigned to taxa Methanobrevibacter millerae decreased (p = 0.090) in PA5 group. Functional annotation of contigs using KEGG database revealed that genes involved in starch and sucrose metabolism were enriched (p = 0.058) in PA5 group compared with control. CAZyme analysis identified genes that encode glycoside hydrolase (GH) accounted for 63.18% and 65.66% of all CAZymes in control and PA5, respectively. The GH2 family (enriched in oligosaccharide-degrading enzymes) genes were greater (p = 0.090) in PA5 than control. Likewise, the abundance of GH26 and GH53 (endo-hemicellulases), GH5_4 (cellulases), and GH13_36 and GH13_42 (α-amylase) were increased (p &lt; 0.1) in PA5 relatively compared with control. Most of the genes were mainly produced by unclassified contigs followed by Cupriavidus oxalaticus and Prevotella ruminicola 23. De novo assembly and binning recovered a total of 107 metagenome-assembled genomes taxonomically assigned to different bacterial phyla and one archaeal phyla. Of these genomes, 39 represented the uncultivated bacteria and 1 represented Lactobacillus genera. This study revealed that PA supplemented steers had increased GH activity, which encode enzymes that efficiently degrade plant cell wall polysaccharides in the rumen thereby increasing the fiber digestibility.

Deep Learning-Based Prediction of the 3D Postorthodontic Facial Changes

With the increase of the adult orthodontic population, there is a need for an accurate and evidence-based prediction of the posttreatment face in 3 dimensions (3D). The objectives of this study are 1) to develop a 3D postorthodontic face prediction method based on a deep learning network using the patient-specific factors and orthodontic treatment conditions and 2) to validate the accuracy and clinical usability of the proposed method. Paired sets (n = 268) of pretreatment (T1) and posttreatment (T2) cone-beam computed tomography (CBCT) of adult patients were trained with a conditional generative adversarial network to generate 3D posttreatment facial data based on the patient's gender, age, and the changes of upper (ΔU1) and lower incisor position (ΔL1) as input. The accuracy was calculated with prediction error and mean absolute distances between real T2 (T2) and predicted T2 (PT2) near 6 perioral landmark regions, as well as percentage of prediction error less than 2 mm using test sets (n = 44). For qualitative evaluation, an online survey was conducted with experienced orthodontists as panels (n = 56). Overall, PT2 indicated similar 3D changes to the T2 face, with the most apparent changes simulated in the perioral regions. The mean prediction error was 1.2 ± 1.01 mm with 80.8% accuracy. More than 50% of the experienced orthodontists were unable to distinguish between real and predicted images. In this study, we proposed a valid 3D postorthodontic face prediction method by applying a deep learning algorithm trained with CBCT data sets.

Metabolite Profile, Ruminal Methane Reduction, and Microbiome Modulating Potential of Seeds of Pharbitis nil

We identified metabolites in the seeds of Pharbitis nil (PA) and evaluated their effects on rumen methanogenesis, fiber digestibility, and the rumen microbiome in vitro and in sacco. Four rumen-cannulated Holstein steers (mean body weight 507 ± 32 kg) were used as inoculum donor for in vitro trial and live continuous culture system for in sacco trial. PA was tested in vitro at doses ranging from 4.5 to 45.2% dry matter (DM) substrate. The in sacco trial was divided into three phases: a control phase of 10 days without nylon bags containing PA in the rumen, a treatment phase of 11 days in which nylon bags containing PA (180 g) were placed in the rumen, and a recovery phase of 10 days after removing the PA-containing bags from the rumen. Rumen headspace gas and rumen fluid samples were collected directly from the rumen. PA is enriched in polyunsaturated fatty acids dominated by linoleic acid (C18:2) and flavonoids such as chlorogenate, quercetin, quercetin-3-O-glucoside, and quinic acid derivatives. PA decreased (p &lt; 0.001) methane (CH4) production linearly in vitro with a reduction of 24% at doses as low as 4.5% DM substrate. A quadratic increase (p = 0.078) in neutral detergent fiber digestibility was also noted, demonstrating that doses &lt; 9% DM were optimal for simultaneously enhancing digestibility and CH4 reduction. In sacco, a 50% decrease (p = 0.087) in CH4 coupled with an increase in propionate suggested increased biohydrogenation in the treatment phase. A decrease (p &lt; 0.005) in ruminal ammonia nitrogen (NH3-N) was also noted with PA in the rumen. Analysis of the rumen microbiome revealed a decrease (p &lt; 0.001) in the Bacteroidetes-to-Firmicutes ratio, suggesting PA to have antiprotozoal potential. At the genus level, a 78% decrease in Prevotella spp. and a moderate increase in fibrolytic Ruminococcus spp. were noted in the treatment phase. In silico binding of PA metabolites to cyclic GMP-dependent protein kinase of Entodinium caudatum supported the antiprotozoal effect of PA. Overall, based on its high nutrient value and antiprotozoal activity, PA could probably replace the ionophores used for CH4 abatement in the livestock industry.

Incidence and Risk Factors for Progression to Diabetes Mellitus: A Retrospective Cohort Study

(1) Objective: This study examined the incidence and risk factors contributing to the progression to diabetes mellitus (DM) in a seven-year follow-up study of non-diabetic National Health Examinees. (2) Methods: For this retrospective observational cohort study, we used two national representative databases: the National Health Screening (HEALS) database 2009 and the National Health Insurance Service (NHIS) database 2009-2015. The eligible subjects without DM with blood sugar levels of <126 mg/dL were selected using the HEALS database. The subsequent follow-up and clinical outcomes were evaluated using the NHIS database. Cox proportional hazard regression was applied to examine the effects of the covariates on progression to diabetes. (3) Results: Among those who took part in the national health screening in 2009, 4,205,006 subjects who met the eligibility criteria were selected. Of these, 587,015 were diagnosed with DM during the follow-up by 2015. The incidence of progression from non-diabetes to DM was 14.0%, whereas that from impaired fasting glucose (IFG) to DM was 21.9%. Compared to the normal group, the newly diagnosed DM group was more likely to comprise older, female, currently smoking, and high-risk drinking participants and participants with IFG, hypertension, dyslipidemia, and metabolic syndrome. (4) Conclusions: This epidemiological study in the Republic of Korea found risk factors similar to those of other studies, but the incidence of progression to DM was 22.8 per 1000 person-years, which is higher than that previously reported. Hence, more care is needed to prevent DM.

Effects of Dietary Protein Concentration on Lipid Metabolism Gene Expression and Fatty Acid Composition in 18-23-Month-Old Hanwoo Steers

The present study evaluated the influence of dietary protein level on growth performance, fatty acid composition, and the expression of lipid metabolic genes in intramuscular adipose tissues from 18- to 23-month-old Hanwoo steers, representing the switching point of the lean-to-fat ratio. Forty steers with an initial live weight of 486 ± 37 kg were assigned to one of two treatment groups fed either a concentrate diet with 14.5% CP and or with 17% CP for 6 months. Biopsy samples of intramuscular tissue were collected to analyze the fatty acid composition and gene expression at 23 months of age. Throughout the entire experimental period, all steers were restrained twice daily to allow individual feeding. Growth performance, blood metabolites, and carcass traits, according to ultrasonic measurements, were not affected by the experimental diets. The high-protein diet significantly increased the expression of intramuscular PPARα (p < 0.1) and LPL (p < 0.05) but did not affect genes involved in fatty acid uptake (CD36 and FABP4) nor lipogenesis (ACACA, FASN, and SCD). In addition, it downregulated intramuscular VLCAD (p < 0.01) related to lipogenesis but also GPAT1 (p = 0.001), DGAT2 (p = 0.016), and SNAP23 (p = 0.057), which are involved in fatty acid esterification and adipocyte size. Hanwoo steers fed a high-protein diet at 18-23 months of age resulted in a relatively lower lipid turnover rate than steers fed a low-protein diet, which could be responsible for shortening the feeding period.

Percutaneous coronary intervention in patients with peripheral artery disease and adverse cardiovascular adverse event and bleeding

Background

Peripheral artery disease (PAD) increase the risk of comorbidity and mortality in coronary artery disease (CAD).

Objectives

We evaluate influence of PAD on prognosis in patients undergoing percutaneous coronary intervention (PCI).

Methods

We analyzed all consecutive patients included in our dedicated local registry for PCI between January 2011 and December 2016. Presence of PAD was defined by decreased ankle-brachial index (&lt;0.9). Major adverse cardiovascular event (MACE) was defined as a composite of cardiovascular death, non-fatal myocardial infarct, revascularization, and ischemic stroke. Major bleeding was defined as Bleeding Academic Research Consortium 3 or 5.

Results

Among the 4,747 patients who underwent the PCI, 12.9% (n=610) of PAD were identified. Old age (&gt;60 years), renal dysfunction, reduced ejection fraction, and presence of PAD were predictors with both MACE and major bleeding event. Among them, presence of PAD was an independent risk factor of MACE and major bleeding (MACE, HR 8.26, 95% CI 2.33- 29.41, p=0.036; major bleeding, HR 3.11, 95% CI 1.10–10.63, p=0.040, respectively). The MACE and major bleeding rate at 5-year was significantly increased in patients with PAD (MACE, 30.0% vs. 15.8%, log rank test p&lt;0.001; major bleeding, 6.7 vs. 3.6%, log rank test p=0.003, respectively) (Figure).

Conclusion

Presence of PAD was strongly associated with higher rate of long-term MACE and major bleeding. These findings could have a clinical relevance in requiring individualized pharmacologic strategies to reduce the burden of cardiovascular disease.

Funding Acknowledgement

Type of funding sources: None.

Impact of active and stable cancer on survival in patients undergoing percutaneous coronary intervention

Background

With advances in treatment of ischemic heart disease and cancer treatment, use of percutaneous coronary intervention (PCI) in cancer survivors and patients with active cancer (AC) is expanding.

Objectives

The purpose of this study was to determine the impact of cancer on survival and major cardiovascular events (MACE) in a long-term, single-center cohort of patients treated with PCI.

Methods

Patients treated with PCI between January 2010 and December 2017 were grouped as follows: controls (patients without cancer), stable cancer (SC), and AC. AC was included patients with cancer diagnosed within the past 6 months, patients who had cancer-related therapy within the past 6 months, active metastatic disease, or active recurrence of the cancer. The primary endpoints were 5-year survival and a secondary endpoint was 5-year MACE.

Results

A total of 6,743 patients (age 66±12 years, 68.4% men) treated with PCI were included: 6,404 (95.0%) controls, 245 (3.6%) SC, and 94 (1.4%) AC. Predominant malignancies were gastrointestinal (37.4%), lung (22.7%), and genitourinary cancer (14.7%). No differences were observed between patients with AC, SC and controls regarding 5-year MACE (total MACE, 33.2% vs. 28.1% vs. 17.5%, p=0.072; cardiac death, 13.6% vs. 9.1% vs. 6.7%, p=0.066; non-fatal myocardial infarction, 2.9% vs. 7.5% vs. 7.8%, p=0.820; revascularization, 17.9% vs. 17.6% vs. 11.6%, p=0.794, respectively). Patients with AC and SC had reduced 5-year survival compared with controls (62.0% vs. 81.5% vs. 89.8%, p&lt;0.001) (Figure). AC was associated with a 1.76 (95% CI 1.22 to 2.54, p=0.002) fold increased risk of all-cause 5-year mortality in multivariable adjusted models.

Conclusions

Cumulative incidence of 5-year survival was discriminated by concurrent status of cancer following PCI. Individualized decision making is needed in the routine practice of PCI regarding concurrent cancer-specific treatment and prognosis.

Funding Acknowledgement

Type of funding sources: None.

Pemetrexed plus cisplatin in patients with previously treated advanced sarcoma: a multicenter, single-arm, phase II trial

Background

Patients with advanced sarcomas have a poor prognosis and few treatment options that improve overall survival. We assessed the efficacy and tolerability of pemetrexed and cisplatin combination therapy in patients with refractory bone and soft tissue sarcoma (STS).

Patients and Methods

Patients were included in this multicenter, phase II study (ClinicalTrials.gov identifier NCT03809637) if they progressed after receiving one or more chemotherapy regimens containing an anthracycline and/or ifosfamide. Pemetrexed was first administered intravenously, followed by cisplatin, over a cycle of 21 days, for a maximum of six cycles. The primary endpoint was a progression-free rate (PFR) at 3 months (3-month PFR).

Results

From January 2017 to September 2019, we enrolled 37 patients; of these, 73% had previously undergone three or more rounds of chemotherapy. Five patients (13.5%) exhibited objective responses, including two patients (2/6, 33.3%) with malignant peripheral nerve sheath tumors, one patient (1/4, 25%) with synovial sarcoma, one patient (1/4, 25%) with undifferentiated pleomorphic sarcoma, and one patient (1/4, 25%) with angiosarcoma. The median progression-free survival was 2.6 months, and the 3-month PFR was 45.9% (n = 17). None of the four patients with osteosarcoma exhibited objective responses or were progression free at 3 months. The most frequent treatment-related grade 3-4 toxicities included neutropenia (16.2%), anemia (13.5%), thrombocytopenia (13.5%), and fatigue (8.1%). Among 26 patients (70.3%) available for immunohistochemical assessments, patients in the low-excision repair cross-complementation group 1 (ERCC1) and low-thymidylate synthase expression groups showed a tendency for longer overall survival.

Conclusions

Combination therapy with pemetrexed and cisplatin was associated with clinically meaningful and sustained responses among patients with advanced and refractory STS. The combination therapy met its predefined primary study endpoint.

•

Pemetrexed and cisplatin show promising efficacy for advanced sarcoma treatment, particularly as a salvage therapy option.

•

The combination therapy met its predefined primary endpoint, with a 3-month PFR of 45.9%.

•

Pemetrexed and cisplatin showed acceptable toxicity in heavily treated sarcoma patients.

Feeding Systems and Host Breeds Influence Ruminal Fermentation, Methane Production, Microbial Diversity and Metagenomic Gene Abundance

Our previous research revealed the advantages of separate feeding (SF) systems compared to total mixed ration (TMR) in terms of ruminal methane (CH₄) production. The purpose of this experiment was to confirm the advantage of SF as a nutritional strategy for CH₄ mitigation, and to determine the effects of different feeding systems (TMR and SF) on the rumen microbiome and associated metagenome of two different breeds and on CH₄ emissions. We randomly allocated four Holstein (305 ± 29 kg) and four Hanwoo steers (292 ± 24 kg) to two groups; the steers were fed a commercial concentrate with tall fescue (75:25) as TMR or SF, in a crossover design (two successive 22-day periods). Neither feeding systems nor cattle breeds had an effect on the total tract digestibility of nutrients. The TMR feeding system and Hanwoo steers generated significantly more CH₄ (P < 0.05) and had a higher yield [g/d and g/kg dry matter intake (DMI)] compared to the SF system and Holstein steers. A larger rumen acetate:propionate ratio was observed for the TMR than the SF diet (P < 0.05), and for Hanwoo than Holstein steers (P < 0.001), clearly reflecting a shift in the ruminal H₂ sink toward CH₄ production. The linear discriminant analysis (LDA) effect size (LEfSe) revealed a greater abundance (α < 0.05 and LDA > 2.0) of operational taxonomic units (OTUs) related to methanogenesis for Hanwoo steers compared to Holstein steers. Kendall’s correlation analysis revealed wide variation of microbial co-occurrence patterns between feeding systems, indicating differential H₂ thermodynamics in the rumen. A metagenome analysis of rumen microbes revealed the presence of 430 differentially expressed genes, among which 17 and 27 genes exhibited positive and negative associations with CH₄ production, respectively (P < 0.001). A strong interaction between feeding system and breed was observed for microbial and metagenomic abundance. Overall, these results suggest that the TMR feeding system produces more CH₄, and that Hanwoo cattle are higher CH₄ emitters than SF diet and Holstein cattle, respectively. Interestingly, host-associated microbial interactions differed within each breed depending on the feeding system, which indicated that breed-specific feeding systems should be taken into account for farm management.

Energy concentration and phosphorus digestibility in meat meal, fish meal, and soybean meal fed to pigs

Objective

The objectives of the present study were to determine digestible energy (DE), metabolizable energy (ME), and standardized total tract digestibility (STTD) of phosphorus (P) in meat meal (MM) and to compare these values with those in fish meal (FM), and soybean meal (SBM) fed to pigs.

Methods

Two experiments were conducted to determine energy concentrations and STTD of P in MM, FM, and SBM fed to growing pigs. In Exp. 1, DE and ME in the 3 test ingredients were measured using 24 barrows with initial body weight (BW) of 77.7±8.3 kg. A corn-based diet and 3 diets containing corn and 22% to 30% of each test ingredient were prepared. In Exp. 2, the STTD of P in the 3 test ingredients was measured using 24 barrows (90.9±6.6 kg BW). Three diets were formulated to contain each test ingredient as the sole source of P.

Results

In Exp. 1, the DE and ME values in MM (3,310 and 2,856 kcal/kg dry matter [DM]) were less (p<0.05) than those in FM (4,121 and 3,572 kcal/kg DM) and SBM (4,390 and 4,032 kcal/kg DM). In Exp. 2, FM (64.3%) had greater (p<0.05) STTD of P than SBM (44.8%) with MM (55.8%) having intermediate STTD of P.

Conclusion

The MM contains less energy concentrations compared with FM and SBM, and digestibility of phosphorus in MM does not differ from that in FM and SBM.

Effects of Olive (Olea europaea L.) Leaves with Antioxidant and Antimicrobial Activities on In Vitro Ruminal Fermentation and Methane Emission

Simple Summary

Olives are cultivated mostly in the Mediterranean as well as in Asia Minor, Korea, Japan, and China. Olive oil is currently used as a food ingredient in human diet, and its consumption is gradually expanding in various countries. Therefore, olive cultivation and oil extraction produce a significant amount of byproducts; providing these byproducts as feed to livestock has been attempted for a long period. Economic, environmental, and nutritional considerations make the use of olive byproducts efficient and cost-effective as feed for ruminants. Among the olive byproducts, olive leaves (OLs) contain higher levels of polyphenols than olive fruits, and have a very high feed value. In this study, it was confirmed that methane production decreased during 12 h of in vitro fermentation, and the number of fat-utilizing microorganisms increased in the 5% OLs group. OLs were found to show antioxidant and antimicrobial activity. Moreover, the proportion of cellulose-degrading bacteria, Fibrobacter succinogenes, Ruminococcus albus, and Ruminococcus flavefaciens increased in the 5% OLs group at 12 h and decreased at 24 h. Olive leaves are believed to be very useful as feed additives and supplements for ruminants.

Abstract

We evaluated whether olive leaves (OLs) are effective as feed additives and supplements for ruminants and the potential methane reduction effects during in vitro fermentation. Two Hanwoo cows (460 ± 20 kg) equipped with cannula were fed Timothy hay and corn-based feed 3% of the body weight at a ratio of 6:4 (8:30 a.m. and 5:00 p.m.). Ruminal fluid from the cows was collected and mixed before morning feeding. In vitro batch fermentation was monitored after 12 and 24 h of incubation at 39 °C, and OLs were used as supplements to achieve the concentration of 5% in the basal diet. At 12 h of fermentation, methane production decreased in the 5% OLs group compared to that in the control group, but not at 24 h. The proportion of cellulose-degrading bacteria, Fibrobacter succinogenes, Ruminococcus albus, and Ruminococcus flavefaciens, tended to increase in the 5% OLs group at 12 h. The amount of ammonia produced was the same as the polymerase chain reaction result for Prevotella ruminicola. At 12 h, the proportion of Prevotella ruminicola was significantly higher in the 5% OLs group. OLs may be used incorporated with protein byproducts or other methane-reducing agents in animal feed.

Vibration reduction during milling of highly flexible workpieces using active workpiece holder system

The milling of highly flexible workpieces, such as thin-walled structures used in turbine blades, aerospace equipment, and jet engine compressors, requires vibration compensation to improve the quality of the workpiece surface. Vibration can be reduced by selecting appropriate cutting parameters. However, this approach reduces system productivity. This paper presents an active workpiece holder that controls the vibration of general computer numerical control machine tools. The proposed holder, which comprises a flexible guide mechanism, driver, and sensor, measures vibration and actively controls it using piezoactuators. A high-rigidity flexure mechanism was designed for the holder, and finite element method simulation and modal analysis were performed. Finally, the proposed system was fabricated, and experimental verification indicated that the system reduced vibration. The surface quality obtained using the controlled system was ∼50% better than that obtained using the uncontrolled system.

Incidence Hypertension and Fasting Blood Glucose from Real-World Data: Retrospective Cohort for 7-Years Follow-Up

This retrospective cohort study was done to investigate the incidence of hypertension and its relation to the fasting blood glucose level in Korea. The eligible non-hypertensive subjects (n = 3,396,187) among the National Health Insurance Service-National Health Screening (NHIS-HEALS) examinees (n = 10,644,911) in 2009 were followed up until 2015. A Cox proportional hazards regression was used to estimate the risk of the high blood glucose level for the incident hypertension while controlling for covariates' confounding effect. The cumulative incidence rate was 10.6% for seven years (11.6% in men and 8.3% in women). The incidence density was 1474.8 per 100,000 person-years. High fasting blood glucose (adjusted Hazard Ratio (aHR), 1.836; 95% confidence interval (CI), 1.810 to 1.862), prediabetes (aHR, 1.249; 95% CI, 1.237 to 1.260), a history of diabetes mellitus (aHR, 1.635; 95% CI, 1.605 to 1.666), high triglyceride (aHR, 1.292; 95% CI, 1.280 to 1.303), a history of dyslipidemia (aHR, 1.279; 95% CI, 1.253 to 1.305) and prehypertension group (aHR, 1.964; 95% CI, 1.948 to 1.979) were significantly related to the incident hypertension after adjusting for covariates. Among real-world data in Korea, high blood glucose level was the independent risk factor for developing hypertension.

Characteristics of silicon nitride deposited by very high frequency (162 MHz)-plasma enhanced atomic layer deposition using bis(diethylamino)silane

Silicon nitrides, deposited by capacitively coupled plasma (CCP)-type plasma enhanced atomic layer deposition (PEALD), are generally applied to today's nanoscale semiconductor devices, and are currently being investigated in terms of their potential applications in the context of flexible displays, etc. During the PEALD process, 13.56 MHz rf power is generally employed for the generation of reactive gas plasma. In this study, the effects of a higher plasma generation frequency of 162 MHz on both plasma and silicon nitride film characteristics are investigated for the purpose of silicon nitride PEALD, using bis(diethylamino)silane (BDEAS) as the silicon precursor, and N₂ plasma as the reactant gas. The PEALD silicon nitride film deposited using the 162 MHz CCP exhibited improved film characteristics, such as reduced surface roughness, a lower carbon percentage, a higher N/Si ratio, a lower wet etch rate in a diluted HF solution, lower leakage current, and higher electric breakdown field, and more uniform step coverage of the silicon nitride film deposited in a high aspect ratio trench, as compared to silicon nitride PEALD using 13.56 MHz CCP. These improved PEALD silicon nitride film characteristics are believed to be related to the higher ion density, higher reactive gas dissociation, and lower ion bombardment energy to the substrate observed in N₂ plasma with a 162 MHz CCP.

180 Screening the carbon footprint of intensive Korean dairy cattle farms: Transition towards low emissions’ production system

In the context of global climate change, carbon footprint (CF) becomes an important sustainability indicator for dairy production systems. To mitigation the CF of the dairy sector, insight into greenhouse gases (GHG) emissions from individual farms is required. The objective of this study was to determine the primary contributors to GHG emissions at the farm-gate level, expressed as a carbon dioxide equivalents (CO2-eq), to produce one kg of fat-and protein corrected milk (FPCM). Primary data about farms’ management and feeding practices were collected from twelve dairy farms that belong to Gyeonggi-do province, which represent the most important region for milk production in South Korea. Allocation of GHG emissions between meat and milk was assessed as a physical allocation, 98% allocated to milk and 2% to meat (surplus of calves and culled cows). The CF of the evaluated farms averaged to 0.61 CO2-eq/kg of FPCM and ranged from 0.49 to 0.78 CO2-eq/kg of FPCM. Results indicated that the largest source of GHG comes mostly from enteric fermentation (83%), followed by manure management (6%), manure and fertilizer land application (8%) and energy consumption (3%). By type of gas emitted, methane accounted for 86% of total emissions, originating from enteric fermentation and manure management. Nitrous oxide and carbon dioxide accounted for 11.6 % and 2.8% of total GHG emissions, respectively. Lactating cows contributed by 70% of total GHG emissions, whereas dry cows, heifers and calves contributed by 5, 22 and 3%, respectively. Differences in GHG emissions from the evaluated farms could be explained by differences in feed quality and management practices through manure and fertilizers application on cropland. This study contributes to identify the main sources of GHG production in dairy farms, which can help to define mitigation strategies towards the transition to neutral carbon emissions of the dairy sector.

219 Developing country specific enteric methane emission factor of the South Korean dairy cattle production using the 2019 refined IPCC Tier 2 methodology

Dairy cattle farming was identified as an important source of enteric methane (CH4) emissions. In order to contribute to the improvement of the national greenhouse gas emission inventory, this work aims to develop emission factors (EF) for CH4 emissions from enteric fermentation in dairy cattle in South Korea. Information on dairy cattle herd characteristics, diet and management practices specific to the Korean dairy cattle population were gathered. EF was estimated according to the 2019 refinement to the 2006 Intergovernmental Panel on Climate Change (IPCC) using the Tier 2 approach. Three animal subcategories were considered: milking cows (650 kg body weight, BW), heifers 1~2 years (473 kg BW) and growing animals &lt; 1 year (167 kg BW). The estimated enteric CH4 EFs for milking cows, heifers 1~2 years, growing animal &lt; 1 year, were 139, 83 and 33 kg/head/year, respectively. South Korea adopted the Tier 1 default enteric CH4 EFs for GHG inventory reporting from the North America region. Compared with the generic Tier 1 default EF of 138 kg CH4/head/year proposed by the 2019 refinement to the 2006 IPCC guidelines for high milking cows, our suggested value is quite similar (139 kg CH4/ head/year). While enteric CH4 EFs values were 23% higher and 49% lower for heifers and growing animals &lt; one year than Tier 1 default EFs values, respectively. In addition, enteric CH4 EF is highly correlated with the level of milk production, feed intake and digestibility and methane conversion factor (%Ym). The outcome of this study underscores the importance of obtaining country-specific EF to estimate national enteric CH4 emissions. Thus, this work is a step forward in the revision of dairy cattle enteric CH4 EF and can further support assessment of mitigation strategies in South Korean livestock farming systems.

Incidence, Long-Term Visual Outcomes, and Mortality in Retinopathy of Prematurity in Korea: A Nationwide Population-Based Study

Purpose

To evaluate the incidence, visual prognosis, and mortality in retinopathy of prematurity (ROP) in Korea.

Methods

We used the National Health Insurance and the Korean Disability Registry database, which covers the entire newborn population in 2006 to 2014 and includes information on all newborns diagnosed with ROP until 2016. Using these databases, we evaluated the incidence, rate of visual impairment (VI), and mortality in patients with ROP according to the birth weight categories and treatment modalities.

Results

The ROP incidence per 1000 newborns was 1.99, which broke down into 317.14 in the very low birth weight (VLBW) less than 1500 g population, 25.45 in the 1500 to 2499 g population, and 0.29 in the 2500 g or greater population. When assessed at age 10, the VI rate was 2.2 per 100 person-years, which was highest at 4.5 per 100 person-years in the VLBW population compared with the population in other birth weight categories. Among treated cases, the proportion of VI in patients undergoing laser photocoagulation or cryotherapy was 1.6% (42/2595), which was lower than the 2.9% (2/68) of patients treated with anti-vascular endothelial growth factor injection, and 32.2% (82/255) of patients undergoing vitrectomy or scleral buckling. The mortality rate was 4.8 per 1000 person-years, which was highest in the VLBW population, but similar across treatment modalities.

Conclusions

The ROP incidence in Korea was approximately 1 in 500 among all newborns, and 1 in 3 in the VLBW population. As the first nationwide population-based study of long-term visual prognosis in ROP, we report the higher VI rate in ROP than previously determined in other studies. Differences in visual outcomes and comparable mortality risks between treatment modalities require further verification.

The Association with rhegmatogenous retinal detachment and paediatric atopic dermatitis: a 12-year Nationwide Cohort Study

PURPOSE

Historically, atopic dermatitis (AD) is associated with an increased risk of rhegmatogenous retinal detachment (RRD). However, uncertainty remained regarding the effect of AD itself and comorbidities (e.g., allergic diseases, cataract surgery) on RRD occurrence in a large, population-based paediatric population.

PATIENTS AND METHODS

We analysed the 12-year National Health Insurance Service database (2002-2013) covering the entire Korean population to estimate the association between AD and RRD in people aged under 20 years.

RESULTS

We identified 3142 RRD patients, and matched 18,852 controls (six controls to each RRD patient); therefore, we included 21,994 peoples under aged 20 years in the analyses. AD was more prevalent in the RRD group (329 patients, 10.47%) than the control group (1043 patients, 5.53%; P < 0.001), and so were severe AD (153 patients [4.87%] and 223 patients [1.18%], respectively; P < 0.001). In conditional logistic regression analysis, AD was associated with RRD (OR, 1.61; 95% CI, 1.93-1.87) even after adjusting for allergic conditions, connective tissue disease, uveitis, and cataract surgery. In addition, severity of AD was associated with an increased risk of RRD (OR for non-severe AD and severe AD, 1.26 [95% CI, 1.05-1.51] and 2.88 [95% CI, 2.25-3.68]).

CONCLUSION

This study suggests that AD itself is a risk factor of RRD in children by showing the association between AD and RRD occurrence and the biologic gradient even after adjustment for known confounders including allergic conditions, uveitis, and cataract surgery.

Development and control of a hybrid active mount module for precision stages

In recent years, precision stages, which are widely used in many industrial fields, have been required to have a higher speed, larger size, and higher precision to help realize higher productivity and product quality. High-performance positioning techniques for inspection and production equipment are classified as one of the most challenging technologies. Vibration control is crucial to realize high-precision positioning technologies. In a precision system, various vibrations exist, which act as disturbances and can degrade the system performance. Minimizing the vibrations generated by the system can, thus, help improve the accuracy of system positioning. This paper proposes a hybrid active mount module for a precision stage. The developed module improves stage performance by reducing the base vibration arising from the floor, minimizing the vibration caused by the driving linear motors of the precision stage, and reducing the settling time by compensating the offset displacement due to the nonlinearity of the passive mount during stage driving. The prototype design is presented herein, and the experimental results demonstrate the potential of the developed device. The developed system is expected to effectively improve the stage performance by controlling the various causes of vibration.

A Study on the Effective Ratio of Fat to Stromal Vascular Fraction for Cell-Assisted Lipotransfer

BACKGROUND

Fat grafting, used for soft tissue augmentation during aesthetic or reconstructive plastic surgery, has disadvantages of low efficiency and unpredictable resorption rate. As an alternative, cell-assisted lipotransfer (CAL) is widely used because of its simplicity and low fat resorption rate. However, relevant studies on optimal CAL parameters are still lacking. Here, we aimed to identify the most effective ratio of fat to stromal vascular fraction (SVF) for CAL.

METHODS

We designed two experimental paradigms. The first involved four groups of mice, each group injected with varying ratios of fat and SVF purified from different amounts of fat from a fixed amount of harvested fat. The second experiment involved four groups of mice, each injected with varying amounts of SVF mixed with a fixed amount of fat tissue. The amount of surviving fat in both experiments was compared 8 weeks after fat transplantation.

RESULTS

In the first experiment, the group injected with only fat, without consuming any of the harvested fat for SVF purification, showed the greatest mean volume and weight. In the second experiment, groups with 1:1 or more ratio of fat to SVF showed greater volume and weight than the group without SVF. Notably, a ratio of 1:1 did not give significantly different results than higher ratios.

CONCLUSIONS

Thus, when a limited amount of fat tissue is available, using all of it for grafting is the most effective. However, if an adequate amount is available, using a fat-to-SVF ratio of 1:1 is the most efficient.

NO LEVEL ASSIGNED

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Ultrafast Transient Spectroscopy of Trans-Polyacetylene in the Midinfrared Spectral Range

Trans-polyacetylene [t-(CH)_{x}] possesses twofold ground state degeneracy. Using the Su-Schrieffer-Heeger Hamiltonian, scientists predicted charged solitons to be the primary photoexcitations in t-(CH)_{x}; this prediction, however, has led to sharp debate. To resolve this saga, we use subpicosecond transient photomodulation spectroscopy in the mid-IR spectral range (0.1-1.5 eV) in neat t-(CH)_{x} thin films. We show that odd-parity singlet excitons are the primary photoexcitations in t-(CH)_{x}, similar to many other nondegenerate π-conjugated polymers. The exciton transitions are characterized by two photoinduced absorption (PA) bands at 0.38 and 0.6 eV, and an associated photoluminescence band at ∼1.5  eV having similar polarization memory. The primary excitons undergo internal conversion within ∼100  fs to an even-parity (dark) singlet exciton with a PA band at ∼1.4  eV. We also find ultrafast photogeneration of charge polarons when pumping deep into the polymer continuum band, which are characterized by two other PA bands in the mid-IR and associated photoinduced IR vibrational modes.

P1443 Sex differences of coronary physiology can be justified by fractional myocardial mass

Purpose

We hypothesized that the gender difference in the anatomical-physiological relationship may elucidate the gender difference in the clinical presentation of coronary artery disease.

Background Women has lower prevalence of coronary artery disease but has higher mortality from acute myocardial infarction. The gender difference in the anatomical-physiological relationship may elucidate the gender difference in the clinical presentation of coronary artery disease.

Methods In this multicenter registry, 482 patients who underwent coronary CT angiography and fractional flow reserve (FFR) measurement were enrolled. Fractional myocardial mass (FMM, a vessel-specific amount of myocardium) and %FMM (fraction of FMM to whole myocardial mass) was measured in major coronary arteries and branches. FFR and quantitative coronary angiography (QCA) were interrogated in the subset of 772 vessels. The severity of physiological or anatomical stenosis was assessed by FFR and diameter stenosis (DS), respectively.

Results In the analysis of all major epicardial arteries (N = 3,833), FMM was lower in women compared to men (p &lt; 0.01, all), but %FMM was similar between women and men (p = NS, all). Among physiologically assessed 772 vessels, compared to men (N = 587), vessels of women (N = 185) showed smaller dimension (reference diameter (RD) = 2.90 ± 0.65 vs 3.14 ± 0.69 mm, minimal luminal diameter (MLD) = 1.30±.0.57 vs 1.40 ± 0.57 mm (p &lt; 0.05, all), similar severity of stenosis (DS = 55% vs 55% p = NS), and higher FFR (0.81 ± 0.13 vs 0.78 ± 0.15, p &lt; 0.001). In subgroup analysis according to the tertiary categories of DS, RD, and MLD, vessels of women showed higher FFR and lower FMM. Generalized estimating equations modeling demonstrated that gender, DS, RD, MLD, and location in left anterior descending artery were not (p = NS, all) but FMM/MLD were significant predictors for FFR ≤ 0.80 (p = 0.021).

Conclusions

Compared to men, coronary arteries of women are smaller and supply smaller amount of myocardium even after adjusting for vessel size, which may explain overall higher FFR value of women. This gender difference in anatomical-physiological relationship may explain the gender difference in the clinical coronary artery disease.

Abstract P1443 Figure.

1175 Comparison of fractional myocardial mass, a vessel-specific myocardial mass-at-risk, with coronary angiographic scoring systems for predicting myocardial ischemia

Aims The burden of coronary artery disease has been assessed by various semi-quantitative angiographic scores, which are frequently different each other. A non-invasive and quantitative modality may substitute angiographic sores for prognostic implication and decision of revascularization strategy. We compared fractional myocardial mass (FMM) with angiographic scores for predicting myocardial ischemia.

Methods In this multicenter registry, 411 patients who underwent coronary computed tomography angiography (CCTA) were followed by invasive coronary angiography and FFR measurement. CCTA–derived %FMM with diameter stenosis ≥70% (%FMM-70) or ≥50% (%FMM-50) were compared with 9 angiographic scores (APPROACH, Duke Jeopardy, BARI, CASS, SYNTAX, Jenkins, BCIS-1, Leaman, Modified Duke) and were tested regarding their performance for predicting FFR ≤ 0.80. Predictive performance of %FMM or angiographic scores for FFR ≤ 0.80 established in derivation cohort (N = 250) and tested in validation cohort (N = 161).

Results The performance of %FMM-70 and %FMM-50 were similar to most angiographic scores (%FMM-70, c-statistics = 0.76; %FMM-50, 0.71; angiographic scores, 0.68 – 0.79). The frequency of FFR ≤ 0.80 increased consistently according to %FMM-70, %FMM-50, and all angiographic scores (p &lt; 0.001, all). The optimal cutoff of %FMM-50 and %FMM-70 for FFR ≤ 0.80 were ≥34.5% and ≥9.8%, respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of %FMM-50 were 83%, 56%, 73%, 70%, 72%, and of %FMM-70 were 72%, 78%, 75%, 75%, and 75% using these cutoffs. Validation cohort showed consistent results.

Conclusion %FMM correlated well with angiographic scores and had a potential to be used as a non-invasive alternative to the angiographic scores. The integration of the severity of stenosis and the amount of subtended myocardium may improve the detection of clinically significant coronary artery stenosis.

Abstract 1175 Figure. FMM vs angiographic score

P1368 Effect of angiotensin receptor blocker in patients with moderate or severe aortic stenosis: a randomized controlled trial

Funding Acknowledgements

This study was supported by grants from Boryung Pharmacy Research Fund.

Background/Introduction: Pathophysiology of aortic stenosis (AS) and several previous studies suggested the potential role of angiotensin receptor blocker (ARB) in patients with AS.

Purpose

We aimed to investigate the effects of Fimasartan, an ARB, on exercise capacity and progression of AS in patients with moderate to severe AS.

Methods

We conducted a prospective, randomized, double-blind, placebo-controlled trial in 32 normotensive or controlled-hypertensive patients with moderate or severe AS. Study participants were randomized to Fimasartan 30 mg to 60 mg daily (n = 14) or placebo (n = 18) for 1 year, and underwent cardiopulmonary exercise test, 6-minute walk test, and echocardiography at 0, 6, and 12 months, with follow-up data available in 29 subjects.

Results

Significant reductions in blood pressures were observed in the Fimasartan group but not in the placebo group. Two of the 14 patients in the Fimasartan group withdrew the study due to mild symptoms probably related with the decreased blood pressure, and one patient decline the study protocol. After the 12-month treatment, the peak oxygen consumption (VO2; the primary outcome) in the Fimasartan group was significantly decreased (from 28.3 ± 5.9 to 25.4 ± 3.8 mL/min/kg, P = 0.021) but not in the placebo group (P for interaction = 0.046) (Figure 1A). The severity of AS showed a gradual progression in both groups, without inter-group differences (mean transaortic pressure; Fimasartan group, +4.0 ± 3.8 mmHg/year; placebo group, +5.3 ± 6.2 mmHg/year; P for interaction = 0.429) (Figure 1B). Parameters of left ventricular systolic and diastolic function did not change in both groups.

Conclusions

The use of ARB impaired exercise capacity in patients with moderate or severe AS, and did not prevent the progression of AS. However, due to the small number of participants, further studies are required to confirm these findings.

Abstract P1368 Figure.

Administration of encapsulated L-tryptophan improves duodenal starch digestion and increases gastrointestinal hormones secretions in beef cattle

Objective

This study investigated the effects of oral administration of rumen-protected L-tryptophan (RPL-T) on duodenal starch digestion and gastrointestinal hormones (GIH) secretions using Hanwoo beef steers as the animal models.

Methods

Four steers (423±24 kg) fitted with ruminal and duodenal cannulas were employed in a crossover design replicated twice. Treatments were control (basal diet) and RPL-T (basal diet+191.1 mg/kg body weight [BW]) group. Blood and duodenal samples were collected to measure serum GIH levels and pancreatic α-amylase activity at day 0, 1, 3, and 5 (−30, 30, 90, 150, and 210 min) of the study. Samples from each segment of the gastrointestinal tract were collected via ruminal and duodenal cannulas and were used to determine soluble protein and the starch digestion rate at days 6 (−30, 180, 360, and 540 min) and 8 (−30, 90, 270, and 450 min) of the experiment.

Results

No significant difference in ruminal pH, NH₃-N, and total volatile fatty acid including the levels of acetate, propionate, butyrate, isobutyrate, valerate, isovalerate, and the acetate-to-propionate ratio was observed between groups (p>0.05). Crude protein uptake was higher and feces starch content was lower in RPL-T group than the control group (p<0.05). The D-glucose contents of feces in RPL-T group decreased at day 5 compared to those in the control group (p<0.05), however, no change was found at day 0, 1, or 3 compared to the control group (p>0.05). Serum cholecystokinin (CCK), melatonin, duodenal pancreatic α-amylase activity, and starch digestion were significantly higher in RPL-T group than the control group (p<0.05).

Conclusion

Taken together, oral administration of RPL-T at the rate of 191.1 mg/kg BW consistently increased CCK concentration, pancreatic α-amylase activity in duodenal fluids, and starch digestion rate in the small intestine and thus found to be beneficial.

Prospectively identifying older adults at risk for potentially avoidable hospitalizations in Korea using population-based data

OBJECTIVE

The purpose of this study is to develop and validate a prediction model to identify older adults at risk for potentially avoidable hospitalizations (PAHs) using variables readily available in routinely collected health administrative data.

DESIGN

Population-based, retrospective observational study using National Health Insurance Service-National Sample Cohort (NHIS-NSC) data.

SETTING

Primary care settings in South Korea.

PARTICIPANTS

The sample includes 113 612 older NHI beneficiaries in the year 2011, among which 2856 had one or more PAHs in 2012.

METHODS

We examined multi-dimensional risk factors of PAHs in the base year and developed and validated prediction models of hospitalization risk using the following year. The predictive power of the developed models was examined with samples generated by the bootstrap method. The performance of the final model was evaluated with further test statistics at different risk thresholds.

MAIN OUTCOME MEASURE

Predicting PAHs.

RESULTS

The c-statistic of the final predictive model was 0.784 (CI: 0.769-0.799). The final model including all selected predictors showed the greatest marginal improvement (integrated discrimination improvement of 365%) compared to the base model. The positive predictive value was good.

CONCLUSIONS

Our prediction model based on health administrative data can assist the insurer and practitioners to proactively identify and intervene with older adults at risk for a PAH.

P1526Pre-dialysis left atrial function assessed by two-dimensional speckle tracking echocardiography as a predictor of upcoming heart failure in hemodialysis patients

Background

Left atrial global longitudinal strain (LA GLS) by 2-dimensional speckle tracking echocardiography is a useful tool to assess LA function and left ventricular (LV) diastolic function. The authors assessed prognostic value of LA GLS, and other diastolic functional parameters in patients undergoing hemodialysis.

Methods

A total of 78 (49 male) patients undergoing hemodialysis who checked echocardiography due to heart failure (HF) symptoms were included for this analysis. Echocardiography wasperformed at the same day of, and before hemodialysis session. Besides conventional echocardiographic measurements, GLS of the LA and the LV were checked and compared. Incidence of rehospitalization due to HF symptoms during mean follow up duration of 381.4±197.5 days was investigated and echocardiographic parameters were compared between patients who experienced rehospitalization and who did not.

Results

16 (20.1%) patients experienced rehospitalization due to HF. HF rehospitalization group had significantly low baseline LV ejection fraction (55.7±7.2 vs. 61.3±7.1%, p=0.006) and LV GLS (14.7±3.4 vs. 18.2±3.9%, p=0.002), while LV geometry (LV end-diastolic volume index and LV wall thickness) did not show significant differences. In HF rehospitalization group, baseline LA function and diastolic function were significantly impaired as reflected by LA GLS (18.8±2.6 vs. 23.8±3.6%, p<0.001), E/E' ratio (20.8±3.3 vs. 15.8±4.6%, p<0.001), and right ventricular systolic pressure (61.4±9.6 vs. 53.4±12.8%, p=0.022). LA end-systolic volume index was not significantly different between the 2 groups. Among various echocardiographic parameters, receiver operation characteristic curve analysis revealed that LA GLS had the strongest power (cutoff value 20.6%, sensitivity 0.813 and specificity 0.790, area under curve 0.849) in prediction of future rehospitalization due to HF.

Predictor of future HF: ROC analysis

Conclusions

The present study demonstrated that functional changes of the LA as measured by LA GLS before hemodialysis session can be used as an echocardiographic parameter to predict future rehospitalization due to HF. Further studies are required to evaluate prognostic value of LA function in predicting other cardiovascular events in hemodialysis patients.

P3520Admission hyperglycemia is a predictor of mortality of acute heart failure: comparison between patients with and without diabetes mellitus

Background

Regardless of diabetes mellitus (DM), admission hyperglycemia is not uncommon in patients with acute heart failure (AHF). Although DM is a well-known predictor of mortality in AHF, the impacts of admission hyperglycemia on clinical outcomes in non-DM patients with AHF have been poorly studied. The aim of this study, therefore, was to compare the impact of admission hyperglycemia on long-term clinical outcomes in AHF patients with or without DM.

Methods

Among 5,625 AHF patients enrolled in a nationwide registry, a total of 5,541 patients were enrolled and divided into 2 groups; DM group (n=2,125, 70.4±11.4 years) vs. non-DM group (n=3,416, 67.3±16.0 years). Each group were further divided into 2 groups according to the presence of admission hyperglycemia (admission serum glucose level >200mg/dl); admission hyperglycemia (n=248) and no hyperglycemia (n=3,168) in non-DM; admission hyperglycemia (n=799) and no hyperglycemia (n=1,326) in DM. All-cause death and hospitalization due to HF (HHF) during 1-year follow-up were compared.

Results

Death was developed in 1,220 patients (22.2%) including 269 inhospital deaths (4.9%) during 1-year of follow-up. Death rate were significantly higher in DM than in non-DM group (24.8% vs 20.5%, p<0.001), however there was no difference in inhospital death (5.1% vs 4.7%, p=0.534). Both inhospital death (7.6% vs. 4.2%, p<0.001) and 1-year death (26.2% vs. 21.3%, p=0.001) were more frequent in AHF patients with hyperglycemia. On Kaplan-Meier survival curve analysis, however, admission hyperglycemia was associated with significantly higher death (p<0.001 by log-rank test) and rehospitalization (p=0.006 by log-rank test) in non-DM group, but not in DM group. In non-DM group, admission hyperglycemia was an independent predictor of 1-year mortality (HR 1.46, 95% CI 1.10–1.93, p=0.009).

Conclusion

DM was a significant predictor of long-term mortality in patients with AHF. Admission hyperglycemia was associated with both higher inhospital and 1-year mortality. The present study also demonstrated that admission hyperglycemia is an independent predictor of mortality in non-DM patients with AHF, but not in DM patients. In addition to the presence of DM, admission hyperglycemia would be a useful marker in the risk stratification of AHF, especially in non-DM patients.

P688Cardiac dysfunction as a predictor of hepatic sinusoidal obstruction syndrome after hematopoietic cell transplantation

Background

Hepatic sinusoidal obstruction syndrome (HSOS) is a well-known fatal complication of hematopoietic cell transplantation (HCT), but the impact of cardiac abnormalities on the occurrence of HSOS has been poorly evaluated. Therefore, the authors investigated whether the structural changes or dysfunction of the heart before HCT is associated with the future occurrence of HSOS.

Methods

A total of 92 patients who underwent HCT were divided into 2 groups; HSOS group (n=11, 6 males, 53.8±15.9 years) vs no HSOS group (n=81, 51 males, 48.6±14.7 years). According to the modified Seattle criteria, HSOS was defined as otherwise unexplained occurrence of 2 or more of the following events within 20 days of HCT; serum total bilirubin >2 mg/dL, hepatomegaly or right upper quadrant pain, sudden weight gain due to fluid accumulation (>2% of baseline body weight). Echocardiography examinations were performed 1 month before HCT, and echocardiographic findings were compared between the groups.

Results

HSOS was developed in 11 patients (12.0%). HSOS group had significantly larger left ventricular end-diastolic volume index (LVEDVI) (65.2±4.9 vs 53.2±6.9 ml/m2, p<0.001) and relatively worse systolic function than no HSOS group (LV ejection fraction: 56.4±3.4 vs 65.1±5.9%, p<0.001, LV global longitudinal strain: −17.9±1.4 vs −20.1±2.0%, p=0.001). LV diastolic functional parameters were also significantly worse in HSOS group than in no HSOS group (E/E' ratio: 11.3±1.8 vs 9.1±2.0, p=0.002, left atrial global longitudinal strain: 27.7±3.3 vs 34.9±5.9%, p<0.001). However, left atrial volume index was not different between the groups (30.8±2.8 vs 29.0±3.3 ml/m2, p=0.078). By receiver operation characteristic curve analysis, among significantly different variables, LVEDVI was the most powerful predictor for HSOS, and the optimal cutoff value was 59.25 mL/m2. (81.8% sensitivity and 77.8% specificity, AUC 0.909).

Predictor of HSOS: ROC analysis

Conclusions

The present study demonstrated that structural changes or dysfunction of the heart are more prevalent in patients with HSOS after HCT and larger LVEDVI, among them, can be a useful predictor of upcoming HSOS. Routine echocardiographic study before HCT would be useful to identify high risk group for HSOS, and the development of HSOS should be carefully monitored in HCT patients with cardiac structural changes or dysfunction on echocardiography.

P671Impacts of echocardiography-defined pulmonary hypertension on clinical outcome in patients with multiple myeloma

Background

Pulmonary hypertension (PH) is a rarely reported complication of multiple myeloma (MM). PH of MM is usually mild to moderate and can be secondary to a variety of conditions, including left ventricular dysfunction, diastolic dysfunction, chronic heart failure, treatment-related toxicity, thrombophilic condition and precapillary involvement. However, only few reports regarding PH in MM incidence and prognosis exist up to now.

Purpose

The purpose of this study was to investigate the risk factors of transthoracic echocardiography-defined PH and its impact on clinical outcome in patients with MM.

Methods

A total of 277 MM patients was included and divided into 2 groups–those non-pulmonary hypertension (PH) or those with PH, based on the results of the transthoracic echocardiography (TTE); PH group (n=143, 60.9±9.2 years, 68 males) versus non-PH group (n=134, 55.9±11.5 years, 72 males). We analyzed propensity score matching and multiple imputation method were used to deal with the missing data in echocardiographic characteristics.

Results

During the follow-up period (median 618 days), all-cause death occurred in 79 (28.5%) patients and 41 patients (14.8%) died from cardiovascular causes (including acute decompensated heart failure, fatal MI, sudden cardiac arrest). In the Kaplan-Meier survival analysis of crude population and propensity-matched population, cumulative overall survival and cardiovascular death (CVD)-free survival were significantly lower in the PH group than in the non-PH group (p<0.001). In propensity-matched population, estimated pulmonary artery pressure >35mmHg in TTE, congestive heart failure, and DM were significant independent predictors of all-cause death.

KM curves in MM stratified by PH

Conclusion

This study demonstrates that the presence of PH, congestive heart failure, and DM is an independent prognostic factor for all-cause death in MM patients with MM. These results highlight the risk associated cardiovascular disease in MM patients and emphasize that management strategies that prevent deterioration of cardiac function are essential.

Hyperprogressive disease during PD-1/PD-L1 blockade in patients with non-small-cell lung cancer

BACKGROUND

Immune checkpoint blockade with Programmed cell death 1 (PD-1)/PD-L1 inhibitors has been effective in various malignancies and is considered as a standard treatment modality for patients with non-small-cell lung cancer (NSCLC). However, emerging evidence show that PD-1/PD-L1 blockade can lead to hyperprogressive disease (HPD), a flair-up of tumor growth linked to dismal prognosis. This study aimed to evaluate the incidence of HPD and identify the determinants associated with HPD in patients with NSCLC treated with PD-1/PD-L1 blockade.

PATIENTS AND METHODS

We enrolled patients with recurrent and/or metastatic NSCLC treated with PD-1/PD-L1 inhibitors between April 2014 and November 2018. Clinicopathologic variables, dynamics of tumor growth, and treatment outcomes were analyzed in patients with NSCLC who received PD-1/PD-L1 blockade. HPD was defined according to tumor growth kinetics (TGK), tumor growth rate (TGR), and time to treatment failure (TTF). Immunophenotyping of peripheral blood CD8+ T lymphocytes was conducted to explore the potential predictive biomarkers of HPD.

RESULTS

A total of 263 patients were analyzed. HPD was observed in 55 (20.9%), 54 (20.5%), and 98 (37.3%) patients according to the TGK, TGR, and TTF. HPD meeting both TGK and TGR criteria was associated with worse progression-free survival [hazard ratio (HR) 4.619; 95% confidence interval (CI) 2.868-7.440] and overall survival (HR, 5.079; 95% CI, 3.136-8.226) than progressive disease without HPD. There were no clinicopathologic variables specific for HPD. In the exploratory biomarker analysis with peripheral blood CD8+ T lymphocytes, a lower frequency of effector/memory subsets (CCR7-CD45RA- T cells among the total CD8+ T cells) and a higher frequency of severely exhausted populations (TIGIT+ T cells among PD-1+CD8+ T cells) were associated with HPD and inferior survival rate.

CONCLUSION

HPD is common in NSCLC patients treated with PD-1/PD-L1 inhibitors. Biomarkers derived from rationally designed analysis may successfully predict HPD and worse outcomes, meriting further investigation of HPD.

Intravenous administration of L-tryptophan stimulates gastrointestinal hormones and melatonin secretions: study on beef cattle

This study aimed to determine the effective dose of intravenous administration of L-tryptophan (L-T) on gastrointestinal hormones (GIH) secretions and melatonin using Hanwoo cattle. Three steers (362 ± 23 kg) fitted with indwelling jugular vein catheters were assigned in a 3 × 3 Latin square design. Treatments were intravenous administration of saline (control), 28.9 mg L-T/kg body weight (BW; low) and 57.8 mg L-T/kg BW (high) L-T for 1 day with 7 days of adaptation. Samples were collected after adaptation period at -60, 0, 30, 60, 90, 120, 150, 180, 240, and 300 min of sampling day. The levels of serum cholecystokinin (CCK) and secretin were higher (p < 0.05) in the high L-T group than those in the other groups. Serum Melatonin (MEL) levels were increased upon L-T administration (p < 0.05) in the high L-T group. Taken together, the effective dose of L-T administration was defined at 57.8 mg L-T/kg BW in order to stimulate increase of GIH and MEL.

Study on the fatty acid profile of phospholipid and neutral lipid in Hanwoo beef and their relationship to genetic variation

Maize which has very high omega-6 fatty acid content has been used as a main feed grain for Hanwoo beef production to increase marbling, and thus omega-6 to omega-3 fatty acids ratio in Hanwoo beef is expected to be biased. To elucidate the current status of omega fatty acids ratio in Hanwoo beef, fatty acid profiles of neutral lipid and phospholipid fraction were analyzed separately using 55 Hanwoo steers’ longissimus dorsi muscle slaughtered at Pyeongchang, Korea from Oct. to Nov. 2015. In addition, an association study was conducted to evaluate associations between single nucleotide polymorphism (SNP) markers from references and omega fatty acid profiles in phospholipid of Hanwoo beef samples using analysis of variance (ANOVA). In neutral lipid fraction, composition of saturated and monounsaturated fatty acids was higher and polyunsaturated fatty acids was lower compared to those in phospholipid fraction. The mean n-6/n-3 ratios of Hanwoo were 56.059 ± 16.180 and 26.811 ± 6.668 in phospholipid and neutral lipid, respectively. There were three SNPs showing statistically significant associations with omega fatty acid content. GA type of rs41919985 in fatty acid synthase (FASN) was significantly associated with the highest amount of C20:5 n-3 (p = 0.031). CC type of rs41729173 in fatty acid-binding protein 4 (FABP4) was significantly associated with the lowest amount of C22:2n-6 (p = 0.047). AG type of rs42187261 in FADS1 was significantly linked to the lowest concentration of C20:4 n-6 (p = 0.044). The total n-6/n-3 ratio of the steer which has all four SNP types in above loci (27.905) was much lower than the mean value of the total n-6/n-3 ratio in phospholipid of the 55 Hanwoo steers (56.059 ± 16.180). It was found that phospholipid and neutral lipid of Hanwoo have very high n-6/n-3 ratios compared to the reported data from different cow breeds. Four SNPs in genes related with fatty acid metabolism showed significant associations with the fatty acid profile of phospholipid and may have potential as SNP markers to select Hanwoo steers in terms of n-6/n-3 balance in the future.

Intra- and Extra-pericardial Lengths of the Superior Vena Cava in Vivo: Implication for the Positioning of Central Venous Catheters

To reduce the possibility of cardiac tamponade, a rare but lethal complication of central venous catheters, the tip of the central venous catheter should be located above the cephalic limit of the pericardial reflection, not only above the superior vena cava-right atrium junction. This study was performed to measure the superior vena cava lengths above and below the pericardial reflection in cardiac surgical patients. Cardiac surgical patients (n=61; 27 male), whose age [mean±SD (range)] was 47±15 (15–75) years, were studied. The intrapericardial and extrapericardial lengths, and the length of the medial duplicated part were measured separately. The whole vertical lengths of the superior vena cava on either side were calculated respectively by adding the intra-and extrapericardial and medial duplication lengths. The lateral extrapericardial was 29.1±6.5 (Mean±SD) (9–49) mm (range), and lateral extrapericardial length was 32.6±6.9 (20–53) mm. The medial extrapericardial length was 23.3±5.0 (11–39) mm, medical duplicated length was 7.2±3.3 (4–20) mm, and medial intrapericardial was 28.3±7.0 (20–52) mm. The averaged superior vena cava length of both sides was 60.3±9.0 (44.5–90) mm. Almost half of the superior vena cava was found to be within the pericardium and half out. This information may be helpful in deciding how far a central venous catheter should be withdrawn beyond the superior vena cava-right atrial junction during right atrial electrocardiographic guided insertion, and in the prediction of optimal central venous catheter insertion depth.