A simplified cranial cavity model to understand the relationship between intracranial pressure and dural sinus pressure

Although accurate intracranial pressure (ICP) monitoring is essential for the diagnosis and treatment of severe brain diseases, current methods are performed invasively. Therefore, a safe and less invasive ICP measurement is required. The purpose of our study was to develop a simplified cranial cavity model for a better understanding of the relationship between the ICP and the pressure measurement within the dural venous sinus (DVS) to support the validity of using sinus pressure as the surrogate of the ICP. The in-house cranial cavity model had three components: the brain part, the DVS part, and the subarachnoid space (SAS) part. Pressure in other parts was measured when the pressure in the SAS part and, separately, brain part was increased from 0 (baseline) to 50 mmHg at intervals of 10 mmHg. When the pressure in the SAS part was increased from 10 to 50 mmHg at 10 mmHg interval, pressures of both the brain and DVS parts increased without significant difference (all P > 0.05). However, pressures in both the SAS and DVS parts differed while the pressure in the brain part was increased. The pressures in both parts showed about 70% of the increase in the brain part. Nevertheless, the pressures in the SAS and DVS parts were not significantly different (P > 0.05). A simplified in-house cranial cavity model was developed consisting of three compartments to represent the actual intracranial spaces. The pressure measurement within the DVS was feasible to use as a surrogate for the ICP measurement.

Can prospective monitoring improve complication rates after gastrectomy? Experience of Billroth I reconstruction at a high-volume tertiary center

INTRODUCTION

Prospective database is imperative in surgical outcome monitoring and has shown success in providing a comprehensive complication index to monitor surgical quality. This study aims to review whether prospective monitoring has an effect on postoperative complication rates, especially leakage after Billroth I (BI) anastomosis and to identify risk factors of anastomosis leakage after BI anastomosis.

MATERIALS AND METHODS

Patients who underwent distal gastrectomy with BI reconstruction at Seoul National University Hospital between January 2018 and April 2021 were enrolled. Clinicopathological characteristics and perioperative variables were retrieved. The risk factor that was statistically significant in univariate analysis was further analyzed by binomial logistic regression analysis.

RESULTS

BI leakage rate in three years has declined by half on a yearly basis from 5.7% to 1.8%. The leakage group patients were predominantly male (100%) when compared to the non-leakage group (67.6%) (p = 0.04). The BMI (25.00 ± 1.42 vs. 24.16 ± 3.15, p = 0.048) and CRP measured on POD#2 (16.47 ± 5.64 vs. 9.99 ± 5.42, p < 0.001) showed significant differences between the two groups. POD#2 CRP greater than 12.7 mg/dL was able to predict risk of anastomosis leak with sensitivity 73.3% and specificity 73.1%.

CONCLUSION

Understanding variations in outcomes is important for improvements in surgical care, and through prospective monitoring and intra-departmental feedback, it is possible to reduce complication rates after gastrectomy. This study shows that age, gender and BMI are risk factors to BI leakage and POD#2 CRP greater than 12.7 mg/dL can be used to suspect leakage after BI anastomosis.

Efficacy and Safety of Image-Guided Hypofractionated Radiotherapy for Hepatocellular Carcinoma with Portal Vein Tumor Thrombosis

PURPOSE/OBJECTIVE(S)

To evaluate the efficacy and safety of image-guided 10-fraction hypofractionated radiotherapy (RT) in hepatocellular carcinoma (HCC) patients with portal vein tumor thrombosis (PVTT).

MATERIALS/METHODS

Between 2016 and March 2022, 69 HCC with PVTT patients received RT (40-50Gy/10fx) in our institutions. The median prescribed dose of 50 Gy (range, 40-50 Gy, BED10; 56-75 Gy10) was delivered in 10 fractions in all patients. Follow-up imaging was performed at three-month intervals after the completion of RT. The extent of PVTT was described according to the Liver Cancer Study Group of Japan classification: Vp0 = no PVTT, Vp1 = segmental portal vein branch, Vp2 = right/left anterior/posterior portal vein, Vp3 = right/left portal vein and Vp4 = main portal vein. Response evaluation was performed using response evaluation criteria in solid tumors, version 1.1. Freedom from local progression (FFLP), progression-free survival (PFS), and overall survival (OS) were calculated from the start date of RT.

RESULTS

In this cohort, 4.3% of patients had Vp1 PVTT, 20.3% had Vp2, 37.7% had Vp3, and 37.7% had Vp4. The median PTV volume was 105.3 cc (interquartile range [IQR], 74.1-179.4 cc). Fifty-two (75.4%) patients received 50 Gy in 10 fractions. With a median follow-up of 10.2 months (IQR, 6-21 months), the median OS was 18.5 months, and 1-year FFLP, PFS, and OS rates were 84.8%, 26.9%, and 62.2% respectively. At 3 months after RT, 13.0% had a complete response, 36.2% had a partial response, 46.4% had a stable disease and 4.4% had a progressive disease. In the multivariate analysis, AFP ≥ 600 IU/ml (HR 2.06, p = 0.03), Child-Pugh Class B or C (HR 2.30, p = 0.02), and modified Union for International Cancer Control (mUICC) stage IVA or IVB (4.05, p = 0.02) were significantly related to OS. During the follow-up period, there were 2 (2.8%) cases of grade ≥3 toxicity: grade 3 AST/ALT elevation (n = 1), and acute cholangitis (n = 1).

CONCLUSION

Hypofractionated RT demonstrated promising local PVTT control with acceptable toxicity. These data suggest that 10-fraction image-guided hypofractionated RT (BED10 = 56-75 Gy10) is a feasible treatment option for PVTT in HCC patients.

Presumed primary cardiac mast cell tumor, pericardial effusion, and arrhythmia in a dog

A 13-year-old female spayed border collie cross presented for pericardial effusion, arrhythmia, and a suspected cardiac mass. Echocardiogram revealed severe thickening and hypokinesis of the interventricular septum with a heterogenous, cavitated myocardium, concerning for neoplasia. Electrocardiogram revealed predominantly accelerated idioventricular rhythm with frequent periods of nonsustained ventricular tachycardia. Occasional prolonged PR intervals terminating in an aberrantly conducted QRS complex were present. These beats were postulated to represent either first-degree atrioventricular block with aberrant QRS conduction or atrioventricular dissociation. Cytology of the pericardial effusion revealed atypical, suspected neoplastic, mast cells. The patient was euthanized, and postmortem examination confirmed full-thickness infiltration of the interventricular septum by a mast cell tumor, with metastasis to the tracheobronchial lymph node and spleen. Given the anatomic location of the mass, the observed atrioventricular nodal conduction delay may represent neoplastic infiltration of the atrioventricular node. Neoplastic infiltration of the ventricle was suspected to cause the accelerated idioventricular rhythm and ventricular tachycardia. To the authors' knowledge, this is the first reported case of a primary cardiac mast cell tumor causing arrhythmia and pericardial effusion in a dog.

Comparison of perioperative outcomes between bipolar sealing, ultrasonic shears and a hybrid device during laparoscopic gastrectomy for early gastric cancer: a prospective, multicenter, randomized study

BACKGROUND

Although EBDs are essential for minimally invasive surgery, well-established prospective randomized studies comparing EBDs are scarce. This study aimed to compare the intraoperative inflammatory response and short-term surgical outcomes among different energy-based devices (EBDs) in laparoscopic distal gastrectomy (LDG).

METHODS

Patients with clinical stage I gastric cancer scheduled for LDG at two different medical centers were prospectively randomized into three groups: ultrasonic shears (US), advanced bipolar (BP) and ultrasonic-bipolar hybrid (HB). The C-reactive protein (CRP) level, operation time, intraoperative blood loss (IBL), laboratory tests, cytokines (interleukin (IL)-6 and IL-10), hospital stay, and complication rate were analyzed. A novel semiquantitative measurement method using indocyanine green (ICG) and a near-infrared camera measured the amount of lymphatic leakage.

RESULTS

The primary endpoint, the CRP level, was significantly lower in the BP (n = 60) group than in the US (n = 57) or HB (n = 57) group [9.03 ± 5.55 vs. 11.12 ± 5.02 vs. 12.67 ± 6.14, p = 0.001, on postoperative day (POD) 2 and 7.48 vs. 9.62 vs. 9.48, p = 0.026, on POD 4]. IBL was significantly lower in BP than in US or HB (26.3 ± 25.3 vs. 43.7 ± 42.0 vs. 34.9 ± 37.0, p = 0.032). Jackson-Pratt drainage triglycerides were significantly lower in BP than in US (53.6 ± 33.7 vs. 84.2 ± 59.0, p = 0.11; HB: 71.3 ± 51.4). ICG fluorescence intensity, operation time, laboratory results, cytokines, hospital stay, and complication rate were not significantly different among the 3 groups.

CONCLUSION

BP showed a lower postoperative CRP level and less IBL than US and HB, suggesting less collateral thermal damage and better sealing function. Surgeons may consider this when selecting EBDs for laparoscopic surgery.

Feasibility and safety of inserting transient biodegradable stents in the pylorus during pylorus-preserving gastrectomy for gastric cancer: a preliminary study in a porcine for proof of concept

BACKGROUND

To evaluate whether insertion of self-biodegradable stent into the pylorus to prevent delayed-gastric emptying after pylorus-preserving gastrectomy is feasible and safe through porcine experiment.

METHODS

Self-biodegradable dumbbell-shaped pyloric stents were designed from absorbable suture materials: poly(glycolide-co-caprolactone) (PGCL) or poly-p-dioxanone (PPDO). After gastrotomy on ten pigs, each stent was inserted: two shams, four PGCL stents, and four PPDO stents. Body weight (Bwt), body temperature (BT), complete blood cell (CBC) count, and plain X-ray were evaluated. On postoperative day (POD) 13, euthanasia was performed for histologic evaluation.

RESULTS

Operation was successfully performed in all ten pigs. Without tagging suture, both stents migrated before POD 3. The migration was delayed up to POD 13, when the tagging sutures (-t) were applied between stent and stomach wall. Self-degradation of PGCL started from POD 3, and stents were completely excreted from the abdomen by POD 8. Although PPDO were also weakened as self-degradation progressed, its shape was maintained in gastrointestinal tract for 13 days. Unexpected sudden death occurred in the pig with PPDO-t2 on POD 10, which is more likely due to acute volvulus rather than stent-related complication. There was no significant difference between three groups in terms of Bwt, BT, CBC, and histology (sham vs. PGCL vs. PPDO, all p > 0.05).

CONCLUSION

The concept of biodegradable stents made of absorbent suture material seems feasible in porcine experiment. Among them, PGCL which has shown rapid absorption, appears to be a more suitable material for transient pyloric absorbable stent when considering safety aspect.

Sex difference in 5-year relative survival following percutaneous coronary intervention

Background

Sex-specific survival following percutaneous coronary intervention (PCI) varies among studies. This might be clarified using relative survival, which adjusts observed survival in relation to that seen in sex- and age-matched general population. We investigated sex-specific relative survival after PCI.

Methods

A total of 48,783 patients were enrolled in the year 2011 Korean nationwide PCI cohort. Primary outcome was all-cause death. Observed and relative survival at 5 years conditional on surviving 0 days, 30 days, 1 year, and 2 years were assessed. Sex-specific differences in cardiovascular risk factors were adjusted via age-group stratified propensity score matching.

Results

In the unadjusted analyses, 15,710 female patients had a higher frequency of cardiovascular risk factors compared with 33,073 male patients. Both observed survival (hazard ratio [HR]=1.28, 95% confidence interval [CI]=1.22–1.34) and relative survival (HR=1.21, 95% CI: 1.16–1.27) were worse in female compared with male (p&lt;0.001, all). In analyses of propensity score-matched 14,454 pairs, female showed a higher observed survival (HR=0.78, 95% CI: 0.74–0.82) but a lower relative survival (HR=1.19, 95% CI: 1.13–1.26) compared with male (p&lt;0.001, all). Neither observed nor relative survival differed between female of age≤50s and age-matched male, but they were lower in female of age≥60s than age-matched male. These findings were consistent in further analyses conditional on surviving 30 days, 1 year, and 2 years.

Conclusions

The 5-year relative survival of female aged≥60 years adjusted by clinical risk factors was lower than that of age-matched male, which mandates the need for the excessive risk reduction in older female undergoing PCI.

Funding Acknowledgement

Type of funding sources: None.

Characterization of rhodanine derivatives as potential disease-modifying drugs for experimental mouse osteoarthritis

OBJECTIVE

This study was performed to characterize selected rhodanine derivatives as potential preclinical disease-modifying drugs for experimental osteoarthritis (OA) in mice.

METHODS

Three rhodanine derivatives, designated rhodanine (R)-501, R-502, and R-503, were selected as candidate OA disease-modifying drugs. Their effects were evaluated by intra-articular (IA) injection in OA mouse models induced by DMM (destabilization of the medial meniscus) or adenoviral overexpression in joint tissues of hypoxia-inducible factor (HIF)-2α or zinc importer ZIP8. The regulatory mechanisms impacted by the rhodanine derivatives were examined in primary-culture chondrocytes and fibroblast-like synoviocytes (FLS).

RESULTS

All three rhodanine derivatives inhibited OA development caused by DMM or overexpression of HIF-2α or ZIP8. Compared to vehicle-treated group, for example, IA injection of R-501 in DMM-operated mice reduced median OARSI grade from 3.78 (IQR 3.00-5.00) to 1.89 (IQR 0.94-2.00, P = 0.0001). R-502 and R-503 also reduced from 3.67 (IQR 2.11-4.56) to 2.00 (IQR 1.00-2.00, P = 0.0030) and 2.00 (IQR 1.83-2.67, P = 0.0378), respectively. Mechanistically, the rhodanine derivatives inhibited the nuclear localization and transcriptional activity of HIF-2α in chondrocytes and FLS. They did not bind to Zn²⁺ or modulate Zn²⁺ homeostasis in chondrocytes or FLS; instead, they inhibited the nuclear localization and transcriptional activity of the Zn²⁺-dependent transcription factor, MTF1. HIF-2α, ZIP8, and interleukin-1β could upregulate matrix-degrading enzymes in chondrocytes and FLS, and the rhodanine derivatives inhibited these effects.

CONCLUSION

IA administration of rhodanine derivatives significantly reduced OA pathogenesis in various mouse models, demonstrating that these derivatives have disease-modifying therapeutic potential against OA pathogenesis.

Enhanced nitrate reductase activity offers Arabidopsis ecotype Landsberg erecta better salt stress resistance than Col-0

The nitrogen utilization efficiency of plants varies depending on the plant species. In modern agriculture, nitrogen fertilizer is used to increase crop production, with the amount of fertilizer addition increasing steadily worldwide. This study included the two most used ecotypes of Arabidopsis thaliana, Landsberg erecta (Ler) and Col-0, which were used to identify differences at the molecular level. We found that the efficiency of nitrogen utilization and salt stress resistance differed between these two ecotypes of the same species. We demonstrated distinct salt stress resistance between Ler and Col-0 depending on the differences in nitrate level, which was explained by different regulation of the NIA2 gene expression in these two ecotypes. Our results demonstrate that the genes and promoters regulate expression of these genes and contribute to trait differences. Further studies are required on genes and promoter elements for an improved understanding of the salinity stress resistance mechanism in plants.

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.

Recovery from Cranial Nerve Symptoms after Flow Diversion without Coiling for Unruptured Very Large and Giant ICA Aneurysms

BACKGROUND AND PURPOSE

Cranial nerve symptoms, including visual impairment and ophthalmoplegia, are one of the most common presentations of very large and giant (≥15 mm) ICA aneurysms. In this study, we evaluated the treatment outcomes of flow diversion and conventional coiling in terms of recovery from cranial nerve symptoms and postoperative complications.

MATERIALS AND METHODS

Seventy-nine patients with unruptured ICA aneurysms of >15 mm who were treated with flow diversion or conventional coiling between December 2009 and December 2020 were retrospectively evaluated. We compared the radiologic and clinical outcomes, including recovery from cranial nerve symptoms, between the 2 groups.

RESULTS

Twenty-eight of 49 patients (57.1%) treated with flow diversion and 10 of 30 patients (33.3%) treated with conventional coiling initially presented with cranial nerve symptoms (P = .068). In the clinical follow-up, the symptom recovery rate was significantly higher in those treated with flow diversion (15 [50%] versus 3 [25%] with conventional coiling, P = .046). Multivariate logistic regression analysis demonstrated that flow diversion was significantly associated with symptom recovery (OR, 7.425; 95% CI, 1.091-50.546; P = .040). The overall postoperative complication rate was similar (flow diversion, 10 [20.4%]; conventional coiling, 6 [20.0%], P = .965), though fatal hemorrhagic complications occurred only in patients with intradurally located aneurysms treated with flow diversion (4 [8.2%] versus 0 [0.0%] with coiling, P = .108).

CONCLUSIONS

Flow diversion without coiling for very large and giant ICA aneurysms yielded a higher rate of recovery from cranial nerve symptoms, but it may be related to an increased hemorrhagic complication rate, especially for intradurally located aneurysms.

Clinical significance of lipid droplets formed in the peritoneal fluid after laparoscopic surgery for gastric cancer

BACKGROUND

Several studies have previously reported that laparoscopic surgery using an energy sealing device generates hazardous surgical smoke. However, the droplets appearing on the surface of peritoneal fluid irrigated with saline, after dissection phase of laparoscopic gastrectomy were ignored for a long time. This study aimed to investigate the composition and clinical significance of these droplet particles.

METHODS

This study prospectively enrolled 15 patients with early gastric cancer (cT1NanyM0) who were scheduled for laparoscopic gastrectomy. Floating phases of peritoneal irrigation fluid containing droplets in dissected area were retrieved before and after surgical dissection. Using gas chromatography analysis, the areas under the peak were compared between the samples retrieved before and after surgical dissection. We also analyzed if the area value with significant change was related to the inflammatory response.

RESULTS

In gas chromatography, the area values after laparoscopic surgical dissection were significantly increased in 10 out of 37 kinds of fatty acids, compared to those before surgical dissection. The significant increase in area value of α-linoleic and eicosadienoic acids were positively correlated with the elevated level of C-reactive protein at postoperative day 2 (Spearman's ρ = 0.843, P < 0.001; Spearman's ρ = 0.785, P = 0.001).

CONCLUSIONS

The lipid droplets, generated after laparoscopic lymphadenectomy during gastric cancer surgery, contained various types of fatty acids, and some of them have been found to be associated with inflammatory response.

Proposal of modified textbook outcome for improving the quality of gastric cancer surgery: A single-center study

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Background: Gastric cancer is one of the leading causes of cancer-related deaths worldwide. Since 2014, the national healthcare quality assessment has been implemented for gastric cancer in Korea, which has the highest incidence. The proportion of early gastric cancer through early detection is high in Korea, and gastric cancer surgery has a great influence on outcome index. The aim of this study is to find indicators that can improve Textbook outcome (TO) in patients undergoing gastric cancer surgery. Comparing with Western data, we intended to propose a modified TO (mTO). Methods: Using a prospective clinical database, we included consecutive cases of gastrectomy for primary gastric cancer between 2014 and 2016. TO was achieved when 10 original indicators proposed by the DUCA group were satisfied. We propose to adjust the index of the number of retrieved lymph nodes from 15 to 30 as the modified TO(mTO) indicator for improving the quality of gastrectomy. For comparison with Western data, we calculated TO, mTO and survival in stage I versus Stage II and III. Results: A total of 2,153 patients were included. TO was achieved in 80.1 percents by 10 original indicators. Most of the indicators showed more than 90 percents of TO satisfaction. Five-year survival was significantly different between the TO (90.0%) and non-TO (76.1%) groups ( P < 0.001). For 608 patients in stage II and III, TO was 72.9 percents, which was much higher than the Western publications. Five-year survival were 74.8 percents for the TO group and 56.8 percents for the non-TO group in stage II and III patients. We found that the number of metastatic lymph nodes increases as the stage increases and even the number of metastatic lymph nodes in stage IIIC exceeded 19. The modified textbook outcome (mTO) for stage II and III was 65.3 percents, and five–year survival was significantly different between mTO (74.0%) and mnon-TO (62.1%) groups ( P < 0.001). To prevent R1 resection and minimize the proportion of remnant total gastrectomy, we performed frozen study examinations of the proximal and distal margins as to ensure high oncological safety. Conclusions: Data from a high volume gastric cancer center showed the high textbook outcome rates. It suggests that the minimum number of lymph node retrievals should be at least 30, even in advanced gastric cancer, and routine intraoperative frozen study examination are necessary to increase R0 resection.

Short-term Outcomes of Pylorus-Preserving Gastrectomy for Early Gastric Cancer: Comparison Between Extracorporeal and Intracorporeal Gastrogastrostomy

Purpose

This study aimed to compare the surgical and oncological outcomes between totally laparoscopic pylorus-preserving gastrectomy (TLPPG) with intracorporeal anastomosis and laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG) with extracorporeal anastomosis.

Materials and Methods

A retrospective analysis was performed in 258 patients with cT1N0 gastric cancer who underwent laparoscopic pylorus-preserving gastrectomy using two different anastomosis methods: TLPPG with intracorporeal anastomosis (n=88) and LAPPG with extracorporeal anastomosis (n=170). The following variables were compared between the two groups to assess the postoperative surgical and oncological outcomes: proximal and distal margins, number of resected lymph nodes (LNs) in total and in LN station 6, operation time, postoperative hospital stay, and postoperative morbidity including delayed gastric emptying (DGE).

Results

The average length of the proximal margin was similar between the TLPPG and LAPPG groups (2.35 vs. 2.73 cm, P=0.070). Although the distal margin was significantly shorter in the TLPPG group than in the LAPPG group (3.15 vs. 4.08 cm, P=0.001), no proximal or distal resection margin-positive cases were reported in either group. The average number of resected LN was similar in both groups (36.0 vs. 33.98, P=0.229; LN station 6, 5.72 vs. 5.33, P=0.399). The operation time was shorter in the TLPPG group than in the LAPPG (200.17 vs. 220.80 minutes, P=0.001). No significant differences were observed between the two groups in terms of postoperative hospital stay (9.38 vs. 10.10 days, P=0.426) and surgical complication rate (19.3% vs. 22.9%), including DGE (8.0% vs. 11.8%, P=0.343).

Conclusions

The oncological safety and postoperative complications of TLPPG with intracorporeal anastomosis are similar to those of LAPPG with extracorporeal anastomosis.

Postoperative quality of life after gastrectomy in gastric cancer patients: a prospective longitudinal observation study

Purpose

The European Organization for Research and Treatment of Cancer quality of life (QOL) questionnaires (QLQ-C30, QLQ-OG25, and QLQ-STO22) are widely used for the assessment of gastric cancer patients. This study aimed to use these questionnaires to evaluate QOL in postgastrectomy patients.

Methods

We prospectively evaluated 106 patients with distal gastrectomy (DG), 57 with pylorus-preserving gastrectomy (PPG), and 117 with total gastrectomy (TG). Body weight and QOL questionnaires were evaluated preoperatively and postoperatively (at 3 weeks, and 3, 6, and 12 months).

Results

TG patients had significantly more weight loss than DG/PPG patients. Compared with DG, patients after PPG had less dyspnea (P = 0.008) and trouble with coughing (P = 0.049), but more severe symptoms of insomnia (P = 0.037) and reflux (P = 0.030) at postoperative 12 months. Compared with DG/PPG, TG was associated with worse body image, dysphagia, eating, and taste in both OG25 and STO22. Moreover, OG25 revealed worse QOL in the TG group with respect to odynophagia, eating with others, choked when swallowing, trouble talking, and weight loss. The QOL of patients who received chemotherapy was worse than those in the chemo-free group in both physical functioning and symptoms such as nausea/vomiting, appetite loss, and trouble with taste; however, these side effects would soon disappear after finishing chemotherapy.

Conclusion

PPG was similar to DG in terms of postoperative QOL and maintaining body weight, while TG was always inferior to both DG and PPG. Adjuvant chemotherapy can affect both body weight and QOL despite being reversible.

Glucose metabolic profiles evaluated by PET associated with molecular characteristic landscape of gastric cancer

BACKGROUND

Although FDG-PET is widely used in cancer, its role in gastric cancer (GC) is still controversial due to variable [¹⁸F]fluorodeoxyglucose ([¹⁸F]FDG) uptake. Here, we sought to develop a genetic signature to predict high FDG-avid GC to plan individualized PET and investigate the molecular landscape of GC and its association with glucose metabolic profiles noninvasively evaluated by [¹⁸F]FDG-PET.

METHODS

Based on a genetic signature, PETscore, representing [¹⁸F]FDG avidity, was developed by imaging data acquired from thirty patient-derived xenografts (PDX). The PETscore was validated by [¹⁸F]FDG-PET data and gene expression data of human GC. The PETscore was associated with genomic and transcriptomic profiles of GC using The Cancer Genome Atlas.

RESULTS

Five genes, PLS1, PYY, HBQ1, SLC6A5, and NAT16, were identified for the predictive model for [¹⁸F]FDG uptake of GC. The PETscore was validated in independent PET data of human GC with qRT-PCR and RNA-sequencing. By applying PETscore on TCGA, a significant association between glucose uptake and tumor mutational burden as well as genomic alterations were identified.

CONCLUSION

Our findings suggest that molecular characteristics are underlying the diverse metabolic profiles of GC. Diverse glucose metabolic profiles may apply to precise diagnostic and therapeutic approaches for GC.

Improved Neutron Lifetime Measurement with UCNτ

We report an improved measurement of the free neutron lifetime τ_{n} using the UCNτ apparatus at the Los Alamos Neutron Science Center. We count a total of approximately 38×10^{6} surviving ultracold neutrons (UCNs) after storing in UCNτ's magnetogravitational trap over two data acquisition campaigns in 2017 and 2018. We extract τ_{n} from three blinded, independent analyses by both pairing long and short storage time runs to find a set of replicate τ_{n} measurements and by performing a global likelihood fit to all data while self-consistently incorporating the β-decay lifetime. Both techniques achieve consistent results and find a value τ_{n}=877.75±0.28_{stat}+0.22/-0.16_{syst}  s. With this sensitivity, neutron lifetime experiments now directly address the impact of recent refinements in our understanding of the standard model for neutron decay.

Postoperative morbidity and quality of life between totally laparoscopic total gastrectomy and laparoscopy-assisted total gastrectomy: a propensity-score matched analysis

BACKGROUND

This study aimed to evaluate the surgical outcome and quality of life (QoL) of totally laparoscopic total gastrectomy (TLTG) compared with laparoscopy-assisted total gastrectomy (LATG) in patients with clinical stage I gastric cancer.

METHODS

From 2012 to 2018, EGC patients who underwent TLTG (n = 223), including the first case with intracorporeal hemi-double stapling, were matched to those who underwent LATG (n = 114) with extracorporeal circular stapling, using 2:1 propensity score matching (PSM). Prospectively collected morbidity was compared between the TLTG and LATG groups in conjunction with the learning curve. The European Organization for Research and Treatment of Cancer (EORTC) QoL questionnaires QLQ-C30, STO22, and OG25 were prospectively surveyed during postoperative 1 year for patient subgroups.

RESULTS

After PSM, grade I pulmonary complication rate was lower in the TLTG group (n = 213) than in the LATG group (n = 111) (0.5% vs. 5.4%, P = 0.007). Other complications were not different between the groups. The learning curve of TLTG was overcome at the 26th case in terms of the comprehensive complication index. The TLTG group after learning curve showed lower grade I pulmonary complication rate than the matched LATG group (0.5% vs. 4.7%, P = 0.024). Regarding postoperative QoL, the TLTG group (n = 63) revealed less dysphagia (P = 0.028), pain (P = 0.028), eating restriction (P = 0.006), eating (P = 0.004), odynophagia (P = 0.023) than the LATG group (n = 21). Multivariate analyses for each QoL item demonstrated that TLTG was the only common independent factor for better QoL.

CONCLUSIONS

TLTG reduced grade I pulmonary complications and provided better QoL in dysphagia, pain, eating, odynophagia than LATG for patients with clinical stage I gastric cancer.

Mapping of the perigastric lymphatic network using indocyanine green fluorescence imaging and tissue marking dye in clinically advanced gastric cancer

BACKGROUND

Using indocyanine green (ICG) fluorescence imaging and tissue marking dyes (TMDs), perigastric lymphatic mapping and their pathological correlation were examined to see whether ICG staining covers all metastatic lymph nodes (LNs) in advanced gastric cancer (AGC).

METHODS

Patients with AGC who underwent open distal or total gastrectomy were enrolled. ICG was serially injected intraoperatively into the subserosa along the greater and lesser curvatures. Stomach specimens were examined under a near-infrared camera. ICG-stained LNs were named, excised, and tattooed with different colored TMDs to retrace the exact location after pathological examinations.

RESULTS

A total of 687 LNs and 69 LN stations were examined from 11 patients. The map of the perigastric lymphatic network showing the topography of ICG-stained and ICG-unstained LNs, including metastatic information, was successfully reconstructed. The average number of ICG-stained and ICG-unstained LNs were 23.6 ± 12.3 (37.8%) and 38.8 ± 17.1 (62.2%), respectively. LN metastases were present in 28 LN stations of 8 patients. Of 8 cases with LN metastases, 40% (11.1-75% per case) of metastatic LNs were stained by ICG. Of 28 metastatic LN stations, 21 (75.0%) were covered by ICG, and actual metastatic LNs were stained in 16 LN stations (57.1%). In 4/8 cases (50%), all metastatic LN stations showed ICG signals.

CONCLUSIONS

ICG fluorescence imaging and TMD are useful tools for visualizing the perigastric lymphatic network and retracing the exact location of ICG-stained LNs in AGC. However, ICG imaging is still not recommended for selective LN dissection in AGC because of the limited staining of perigastric LNs.

Erratum to: Radiologic intervention due to delayed gastric emptying after pylorus preserving gastrectomy for gastric cancer does not affect pyloric function

[This corrects the article on p. 89 in vol. 16.].

Predictors of the Effects of Flow Diversion in Very Large and Giant Aneurysms

BACKGROUND AND PURPOSE

The treatment paradigm for very large and giant aneurysms has recently changed to flow diversion, in light of the results of the Pipeline for Uncoilable or Failed Aneurysms trial. However, the effects of flow diversion were definitely unknown. We explored this topic and identified the predictors of such effects.

MATERIALS AND METHODS

We retrospectively reviewed 51 patients with unruptured aneurysms admitted to our institution for flow diversion between February 2014 and August 2019. Patients were categorized into an effect group (no filling or remnant entry) and a no-effect group (subtotal or total filling). We evaluated the aneurysm size and shape, incorporation vessel, parent artery stenosis and curvature, stagnation of contrast medium within the aneurysm, use of balloon angioplasty, and intra-aneurysm thrombus as potential predictors of the effects of flow diversion.

RESULTS

The effect group comprised 34 patients (66.7%, 34/51; no filling, 35.3%, 18/51; and remnant entry, 31.4%, 16/51). The no-effect group comprised 17 patients (33.3%, 17/51; subtotal filling, 29.4%, 15/51; and total filling, 3.9%, 2/51). An incorporation vessel and balloon angioplasty were independent risk factors for the no-effect group in multivariate logistic regression analyses (OR = 0.13 and 0.05; 95% confidence intervals, 0.02-0.62 and 0.00-0.32; P values, .021 and .004, respectively).

CONCLUSIONS

Flow diversion is effective for very large and giant aneurysms, but the outcomes require further improvement. The results of this study show that an incorporated vessel and excessive balloon angioplasty might compromise flow diversion. This finding can help improve the outcomes of flow diversion.

Ultracold neutron properties of the Eljen-299-02D deuterated scintillator

In this paper, we report studies of the Fermi potential and loss per bounce of ultracold neutrons (UCNs) on a deuterated scintillator (Eljen-299-02D). These UCN properties of the scintillator enable its use in a wide variety of applications in fundamental neutron research.

Prediction Model for Screening Patients at Risk of Malnutrition After Gastric Cancer Surgery

BACKGROUND

Malnutrition after gastrectomy is associated with a poor prognosis; however, no accurate model for predicting post-gastrectomy malnutrition exists. Hence, we conducted a retrospective study to develop a prediction model identifying gastric cancer patients at high risk of malnutrition after gastrectomy.

METHOD

Gastric cancer patients who underwent curative gastrectomy with more than one weight measurement during a 3-year follow-up period were included. Malnutrition was defined as body mass index (BMI) < 18.5 kg/m² according to the European Society of Clinical Nutrition and Metabolism diagnostic criteria. BMI-loss pattern was analyzed using a group-based trajectory model. A prediction model for malnutrition 6 months after gastrectomy was developed based on significant risk factors, and then validated.

RESULTS

Overall, 1421 patients were examined. The BMI-loss trajectory model showed significant BMI loss at 6 months after gastrectomy. Severe BMI loss (mean 21.5%; n = 109) was significantly associated with the elderly, female sex, higher preoperative BMI, advanced cancer stage, open surgery, total gastrectomy, Roux-en-Y reconstruction, chemotherapy, and postoperative complications (all p < 0.05). Malnutrition 6 months after gastrectomy was observed in 152 (11.9%) of 1281 patients. Preoperative BMI, sex, and type of operation were included in the final prediction model as predictive factors (p < 0.05). The C-index of the developmental set and bootstrap validation of the prediction model was 0.91 (95% confidence interval 0.89-0.94) and 0.91, respectively.

CONCLUSION

The prediction model for the risk of malnutrition 6 months after gastrectomy was accurately developed, with three independent risk factors: low preoperative BMI, female sex, and total or proximal gastrectomy.

The RNA-Binding Protein DDX18 Promotes Gastric Cancer by Affecting the Maturation of MicroRNA-21

Objectives

The noncoding RNAs (ncRNAs) play important roles in gastric cancer. Most studies have focused on the functions and influence of ncRNAs, but seldom on their maturation. DEAD box genes are a family of RNA-binding proteins that may influence the development of ncRNAs, which attracted our attention. By combining a small sample for high-throughput gene microarray screening with large samples of The Cancer Genome Atlas (TCGA) data and our cohort, we aimed to find some gastric cancer-related genes. We evaluated the clinical significance and prognostic value of candidate gene DDX18, which is overexpressed in gastric cancer tissues. To provide a theoretical basis for the development of new therapeutic targets for the treatment of gastric cancer, we investigated its effect on the malignant biological behavior of gastric cancer in vitro and in vivo, and also discuss its mechanism of action.

Methods

(i) The differential profiling of mRNA expression in five pairs of gastric cancer and adjacent normal tissues was studied by Arraystar Human mRNA Microarray. By combining this with TCGA data and our cohort, we finally filtered out DDX18, which was upregulated in gastric cancer tissues, for further investigation. (ii) The protein expression of DDX18 was detected by immunohistochemistry staining. Then the relationship between the DDX18 expression level and the clinicopathological data and prognosis was analyzed. (iii) A CCK-8 assay and colony formation assay were used to evaluate the effect of DDX18 on cell growth and proliferation in vitro. A transwell assay was also performed to examine the migration and invasion of gastric cancer cells. Cell apoptosis was analyzed by using a fluorescein isothiocyanate–annexin V/propidium iodide double-staining assay. To identify the role of DDX18 in the tumorigenic ability of gastric cancer cells in vivo, we also established a subcutaneous gastric cancer xenograft model. Coimmunoprecipitation, small RNAseq, and western blotting were performed to explore the mechanism of action of DDX18 in gastric cancer. A patient-derived xenograft (PDX) model was used to confirm the effect of DDX18 in gastric cancer tissues.

Result

(i) DDX18 was upregulated in gastric cancer tumor tissues from a TCGA database and our cohort. The expression of DDX18 was also closely related to tumor volume, Borrmann classification, degree of tumor differentiation, cancer embolus, lymph node metastasis, and TNM stage. (ii) DDX18 could promote cell proliferation, migration, and invasion and inhibit cell apoptosis in vivo and in vitro. (iii) DDX18 could promote the maturation of microRNA-21 through direct interaction with Drosha, decreasing PTEN, which could upregulate the AKT signaling pathway. (iv) The PDX model showed that DDX18 could promote the proliferation of gastric cancer tissues by means of the PTEN–AKT signaling pathway.

Conclusions

(i) DDX18 can be treated as a molecular marker to assess the prognosis of patients with gastric cancer. (ii) DDX18 could be a potential therapeutic target in gastric cancer.

Preservation of hepatic branch of the vagus nerve reduces the risk of gallstone formation after gastrectomy

BACKGROUND

Injury to the vagus nerve has been proposed to be associated with occurrence of gallstones after gastrectomy. We investigated the effect of preservation of hepatic branch of the vagus nerve on prevention of gallstones during laparoscopic distal (LDG) and pylorus-preserving gastrectomy (LPPG).

METHODS

Preservation of the vagus nerve was reviewed of cT1N0M0 gastric cancer patients underwent LDG (n = 323) and LPPG (n = 144) during 2016-2017. Presence of gallstones was evaluated by ultrasonography (US) and computed tomography (CT). Incidences of gallstones were compared between the nerve preserved (h-DG, h-PPG) group and sacrificed (s-DG, s-PPG) group. Clinicopathological features were also compared.

RESULTS

The 3-year cumulative incidence of gallstones was lower in the h-DG (2.7%, n = 85) than the s-DG (14.6%, n = 238) (p = 0.017) and lower in the h-PPG (1.6%, n = 123) than the s-PPG (12.9%, n = 21) (p = 0.004). Overall postoperative complication rate was similar between the h-DG and s-DG (p = 0.861) as well as between the h-PPG and s-PPG (p = 0.768). The number of retrieved lymph nodes station #1 and 3-year recurrence-free survival were not significantly different between the preserved group and sacrificed group. Injury to the vagus nerve (p = 0.001) and high body mass index (BMI) (≥ 27.5 kg/m²) (p = 0.040) were found to be independent risk factors of gallstone formation in multivariate analysis.

CONCLUSIONS

Preservation of hepatic branch of the vagus nerve can be recommended for LDG as well as LPPG of early gastric cancer patients to reduce postoperative gallstone formation.

Radiologic intervention due to delayed gastric emptying after pylorus preserving gastrectomy for gastric cancer does not affect pyloric function

Purpose

The purpose of this study is to evaluate whether radiologic intervention in the pylorus decreases its function for delayed gastric emptying (DGE) patients after pylorus preserving gastrectomy (PPG) for gastric cancers and to determine the optimal interventional algorithm.

Methods

PPG patients who underwent intervention for DGE from January 2013 to December 2017 and a control group using propensity score matching were identified. Pyloric function was compared by subjective symptoms, postoperative upper gastrointestinal series at 3 months (short-term function), and esophagogastroduodenoscopy findings at 12 months (long-term function). Serum albumin levels and body weight change, 6 months and 12 months postoperatively, were compared to evaluate nutritional status. Interventional success rate, mean hospital stay, and recurrence of DGE were analyzed to determine the optimal intervention plan.

Results

Fifty-one out of 677 patients (7.53%) received intervention. There was no difference in pyloric function and nutritional status between the intervention and control groups. The interventional success rate for first-time balloon dilatation was 41.7% (20/48). If a second intervention was required and balloon dilatation was done, the success rate was 45.5% (5/11). However, if stent insertion was done, the success rate was 100% (17/17). Subsequent stent insertion after balloon dilatation resulted in a shorter mean hospital stay. Intervention including stent insertion had a lower recurrence of DGE than balloon only intervention (1.96% vs. 5.88%, P=0.041).

Conclusion

Radiologic intervention did not decrease long-term pyloric function. For treating DGE, if at first balloon dilatation fails, retrievable stent insertion can be considered as a second choice.

A Size-Selectively Biomolecule-Immobilized Nanoprobe-Based Chemiluminescent Lateral Flow Immunoassay for Detection of Avian-Origin Viruses

In this study, a signal-amplifiable nanoprobe-based chemiluminescent lateral flow immunoassay (CL-LFA) was developed to detect avian influenza viruses (AIV) and other contagious and fatal viral avian-origin diseases worldwide. Signal-amplifiable nanoprobes are capable of size-selective immobilization of antibodies (binding receptors) and enzymes (signal transducers) on sensitive paper-based sensor platforms. Particle structure designs and conjugation pathways conducive for antigen accessibility to maximum amounts of immobilized enzymes and antibodies have advanced. The detection limit of the CL-LFA using the signal-amplifiable nanoprobe for the nucleoprotein of the H3N2 virus was 5 pM. Sensitivity tests for low pathogenicity avian influenza H9N2, H1N1, and high pathogenicity avian influenza H5N9 viruses were conducted, and the detection limits of CL-LFA were found to be 10^3.5 50% egg infective dose (EID₅₀)/mL, 10^2.5 EID₅₀/mL, and 10⁴ EID₅₀/mL, respectively, which is 20 to 100 times lower than that of a commercial AIV rapid test kit. Moreover, CL-LFA demonstrated high sensitivity and specificity against 37 clinical samples. The signal-amplifiable probe designed in this study is a potential diagnostic probe with ultrahigh sensitivity for applications in the field of clinical diagnosis, which requires sensitive antigen detection as evidenced by enhanced signaling capacity and sensitivity of the LFAs.

Prognostic Impact of Frozen Section Investigation and Extent of Proximal Safety Margin in Gastric Cancer Resection

BACKGROUND AND AIMS

Guidelines propose different extents of macroscopic proximal margin for gastric cancer and frozen margin investigation in selected cases, but data is lacking. This study was to evaluate the necessary extent of macroscopic proximal margin, accuracy of frozen margin investigation, and prognostic impact of tumor-free proximal margin length in pT2-pT4 gastric cancer.

STUDY DESIGN

Proximal and distal frozen margins were routinely investigated intraoperatively in all pT2-pT4 gastric cancers resected between 2011 and 2017. Macroscopic and microscopic proximal margin lengths were correlated. For R0-resections, survival analysis was performed for distal gastrectomy (DG) with microscopic proximal margin length ≤3 cm versus >3 cm.

RESULTS

Overall, 1484 patients were included. Microscopic proximal margin lengths were macroscopically more often misestimated in diffuse histology (P = 0.0004), but extent of underestimation in centimeter was similar to intestinal and mixed/undetermined type (P = 0.134). Fifteen cases (1.0%) resulted in R1-resection, 10 at distal, and 5 at proximal margin but none with macroscopic proximal margin ≥3 cm and negative frozen section. Overall agreement of frozen margin and final pathology was 2951/2968 (99.4%). Proximal margin length in DG did not correlate with survival or recurrence in R0-resected patients.

DISCUSSION

Diffuse histology is at higher risk for underestimation of proximal margin length, but extent of underestimation is similar in other Laurén subtypes. If ≥3 cm macroscopic proximal margin length is applied with intraoperative frozen margin confirmation, R1-resection can be avoided.

CONCLUSION

In pT2-T4a gastric cancer, proximal margin of ≥3 cm plus frozen margin confirmation provides high oncological safety. In DG patients with R0-resection, proximal margin length does not correlate with survival or recurrence.

Search for Sub-eV Sterile Neutrinos at RENO

We report a search result for a light sterile neutrino oscillation with roughly 2200 live days of data in the RENO experiment. The search is performed by electron antineutrino (ν[over ¯]_{e}) disappearance taking place between six 2.8 GW_{th} reactors and two identical detectors located at 294 m (near) and 1383 m (far) from the center of the reactor array. A spectral comparison between near and far detectors can explore reactor ν[over ¯]_{e} oscillations to a light sterile neutrino. An observed spectral difference is found to be consistent with that of the three-flavor oscillation model. This yields limits on sin^{2}2θ_{14} in the 10^{-4}≲|Δm_{41}^{2}|≲0.5  eV^{2} region, free from reactor ν[over ¯]_{e} flux and spectrum uncertainties. The RENO result provides the most stringent limits on sterile neutrino mixing at |Δm_{41}^{2}|≲0.002  eV^{2} using the ν[over ¯]_{e} disappearance channel.

The pattern of postoperative quality of life following minimally invasive gastrectomy for gastric cancer: a prospective cohort from Korean multicenter robotic gastrectomy trial

Purpose

Quality of life (QOL) has become important in the trend of emphasizing patient satisfaction. This study aimed to evaluate the QOL in patients who underwent laparoscopic or robotic gastrectomy for gastric cancer.

Methods

A prospective trial was performed involving patients who underwent laparoscopic or robotic gastrectomy for primary gastric cancer at 11 hospitals in Korea. Within this comparative trial, QOL, postoperative pain, and long-term complications were exanimated. The quality-of-life questionnaire (QLQ)-C30 and QLQ-STO22 developed by the European Organization for Research and Treatment of Cancer were used for the QOL survey. We compared the data after dividing it into several types of characteristics as follows; device (robotic or laparoscopic), operation type, pathological stage, and sex. Biased components were extracted by logistic regression analysis. Propensity score matching was applied to the data set with the biased components.

Results

In total, 434 patients (211 for laparoscopic surgery and 223 for robotic surgery) were enrolled, out of which 321 patients who responded to both preoperative and postoperative surveys were selected for analysis. Robotic gastrectomy was not different from laparoscopic gastrectomy with respect to postoperative QOL. Distal gastrectomy showed better scores than total gastrectomy in terms of role functioning, social functioning, fatigue, nausea/vomiting, pain, dyspnea, constipation, financial difficulties, dysphagia, eating restrictions, anxiety, taste, and body image. Male patients showed better scores on the 19 scales compared to female patients.

Conclusion

Robotic and laparoscopic approaches for gastric cancer surgery did not differ from each other with respect to QOL. Distal gastrectomy resulted in better QOL than total gastrectomy.

Clinical outcome of implants placed in grafted maxillary sinus via lateral approach: A 10-year follow-up study

Background/purpose

The maxillary sinus floor augmentation (MSFA) technique is frequently used for the preparation of implant sites in the maxillary region. The aim of this study was to investigate the 10-year outcome of dental implants placed in a grafted maxillary sinus, and identify possible risk factors for implant failure.

Materials and methods

We retrospectively analyzed 202 implants after MSFA in 97 patients from January 2008 to April 2009. The outcome variables were 1) 10-year cumulative survival rate of the implant, 2) risk factors for implant failure, and 3) correlation between preoperative residual bone height (RBH) and graft materials in terms of implant survival. Graft materials used were divided into five different groups: autogenic, allogenic, xenogenic, combination of allogenic and xenogenic, or combination of autogenic and xenogenic graft.

Results

The cumulative 10-year survival rate for the implants was 96.04%. In regions with a residual bone height of 5.0 mm and less, greater RBH was preferable for long-term implant survival (odds ratio = 3.475; p = 0.035). Implant survival was not significantly different with different graft materials, even when RBH was unfavorable.

Conclusion

The placement of dental implants with MSFA is a reliable procedure. Further, RBH is an important predictor of long-term implant survival.

Proximal Anterior-Antrum Posterior (PAAP) Overlapping Anastomosis in Minimally Invasive Pylorus-Preserving Gastrectomy for Early Gastric Cancer Located in the High Body and Posterior Wall of the Stomach

Purpose

To evaluate the feasibility and safety of intracorporeal overlapping gastrogastrostomy between the proximal anterior wall and antrum posterior wall (PAAP; PAAP anastomosis) of the stomach in minimally invasive pylorus-preserving gastrectomy (PPG) for early gastric cancer (EGC).

Materials and Methods

From December 2016 to December 2019, 17 patients underwent minimally invasive PPG with PAAP anastomosis for EGC in the high body and posterior wall of the stomach. Intraoperative gastroscopy was performed with the rotation maneuver during proximal transection. A longer antral cuff (>4-5 cm) was created for PAAP than for conventional PPG (≤3 cm) at the point where a safe distal margin and good vascular perfusion were secured. Because the posterior wall of the proximal remnant stomach was insufficient for intracorporeal anastomosis, the anterior wall was used to create an overlapping anastomosis with the posterior wall of the remnant antrum. The surgical and oncological outcomes were analyzed, and the stomach volume was measured in patients who completed the 6-month follow-up. The results were compared to those after conventional PPG (n=11 each).

Results

PAAP anastomosis was successfully performed in 17 patients. The proximal and distal resection margins were 2.4±1.9 cm and 4.0±2.6 cm, respectively. No postoperative complications were observed during the 1-year follow-up esophagogastroduodenoscopy (n=10). The postoperative remnant stomach (n=11) was significantly larger with PAAP than with conventional PPG (225.6±118.3 vs. 99.1±63.2 mL; P=0.001). The stomach length from the anastomosis to the pylorus was 4.9±2.4 cm after PAAP.

Conclusions

PAAP anastomosis is a feasible alternative for intracorporeal anastomosis in minimally invasive PPG for highly posteriorly located EGC.

Intraprocedural Flat Panel Detector Rotational Angiography and an Image Fusion Technique for Delivery of a Microcatheter into the Targeted Shunt Pouch of a Dural Arteriovenous Fistula

The accurate and safe delivery of a microcatheter to a targeted shunt pouch is essential for successful transvenous embolization of intracranial dural arteriovenous fistulas. However, complex anatomy and variations in head and neck veins and occluded sinuses can hinder intraprocedural microcatheter delivery. In this study, we introduce an intraprocedural flat panel detector rotational angiography and image fusion technique to aid precise navigation inside the veins and proper placement of the microcatheter in the targeted shunt pouch.

Cesium Lead Bromide Quantum Dot Light-Emitting Field-Effect Transistors

Solution-processable perovskite quantum dots are considered as promising optical materials for light-emitting optoelectronics. Light-emitting field-effect transistors (LEFETs) that can be operated under a relatively lower potential with a high energy conversion efficiency are yet to be realized with perovskite quantum dots. Here, we present the CsPbBr₃ quantum dot-based LEFET. Surprisingly, unipolar transport characteristics with strong electroluminescence were observed at the interface of the CsPbBr₃ QD-LEFET along with an exceptionally wide recombination zone of 80 μm, an order of magnitude larger than that of organic/polymer LEFETs. Based on the systematic analysis for the electroluminescence of the CsPbBr₃ NC-LEFET, we revealed that the increased diffusion length determined by the majority carrier mobility and the lifetime well explains the remarkably wide recombination zone. Furthermore, it was found that the energy-level matching and transport geometry of the heterostructure also determine the charge distribution and recombination, substantially affecting the performance of the CsPbBr₃ QD LEFET.

Dependence of the V/III Ratio on Indium Incorporation in InGaN Films Grown by Metalorganic Vapour Phase Epitaxy

InGaN epitaxial layers were grown on c-plane sapphire substrates using the metalorganic vapour phase epitaxy (MOVPE) system at 760 °C. By varying the total flow rate of group-III sources (TMI+TEG) with a fixed molar ratio of group-III sources [TMI/(TMI+TEG)], the influence of V/III ratio were investigated from 4500 to 20000. The grown N-polar InGaN layers were investigated by atomic force microscopy and it is found that the surface roughness decreases with increasing the V/III ratios. High resolution X-ray diffraction analyses show that the phase separation decreases with increasing the V/III ratios. Photoluminescence measurements reveal that the peak position of the band-edge emission shifted toward the shorter wavelength with increasing the V/III ratios. Reciprocal space mapping (RSM) analyses were carried out on InGaN films. At low V/III ratio, the phase separation can be detected in InGaN films.

Development of a gene panel for 18F-FDG PET positivity prediction in gastric cancer

420

Background: 18F-FDG PET is widely used in clinical cancer diagnostics. However, 18F-FDG PET scan in gastric cancer (GC) is still controversial because of its lower sensitivity in diagnosis and staging compared to other imaging modalities. The purpose of this study was to establish a gene panel for 18F-FDG PET positivity in GC by using patient-derived xenografts (PDXs). Methods: BALB/c nude mice were subcutaneously implanted with 30 cases of GC PDX tissues and underwent a simultaneous PET/MRI scanner. Using RNA-seq data of the 30 GC PDXs for training set, we constructed a gene co-expression network which was correlated with the maximal standardized uptake values (SUVmax). The least absolute shrinkage and selection operator (LASSO) was used for identification of genomic signature for the PET positivity and a prediction model was established. By using qRT-PCR, a gene panel (PredictionScore) based on the gene signature was developed. Results: We found that the PDXs could recapitulate FDG avidity of those parental tumors between 15 Patient-PDX pairs (Spearman r = 0.54, p-value = 0.04). The prediction model with the identified five genes ( PLS1, PYY, HBQ1, SLC6A5, NAT16) provided excellent prediction values compared with actual SUVmax for 15 patients as a validation set (Spearman r = 0.56, p-value = 0.03) and for 8 patients as a test set (Spearman r = 0.90, p-value = 0.005). The PredictionScore showed significant positive correlation with the actual SUVmax for 7 patients as an external validation set (Spearman r = 0.82, p-value = 0.03). Conclusions: PDX can be used to develop a gene panel for the PET positivity prediction in GC. Our results showed that the scoring system can be clinically applicable for developing a predicted stratification model. Future studies will aim to evaluate the panel for a higher number of PET-scanned GC patients to establish a rational patient selection for PET scan in clinical settings.

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

Topically applied treatments for external genital warts in nonimmunocompromised patients: a systematic review and network meta-analysis

Selecting a topical treatment from among the numerous topical agents for external genital warts remains challenging without clear evidence. Our aim was to evaluate comparatively the efficacy and safety of topical agents for external genital warts using a network meta-analysis. We included all randomized controlled trials that evaluated any topically applied treatment for external genital warts. Using the R package netmeta, network meta-analyses were performed with a frequentist approach. We identified 41 relevant studies comprising 6371 patients. Among conventional agents, podophyllotoxin 0·5% solution (odds ratio 1·94, 95% confidence interval 1·02-3·71) was significantly more efficacious than imiquimod 5% cream for lesion clearance; however, it was associated with a higher overall adverse event rate. Sinecatechins 15% ointment (odds ratio 0·21, 95% confidence interval 0·12-0·34) was significantly less efficacious than imiquimod 5% cream. Idoxuridine, polyhexamethylene biguanide, cidofovir and SB206 showed comparable therapeutic efficacies with conventional therapies. None of the treatments were significantly different from each other with respect to recurrence, patients with severe adverse events, or patients who withdrew because of treatment-related adverse events. Conventional modalities were efficacious and well tolerated, although each of them had their advantages and disadvantages. Additional efficacy and safety studies are warranted for unconventional agents.

The Fate of Unruptured Intracranial Vertebrobasilar Dissecting Aneurysm with Brain Stem Compression According to Different Treatment Modalities

BACKGROUND AND PURPOSE

Unruptured intracranial vertebrobasilar dissecting aneurysms with brain stem compression are difficult to treat. In the present study, the clinical and radiologic outcomes of unruptured intracranial vertebrobasilar dissecting aneurysms with brain stem compression based on different treatment modalities were evaluated.

MATERIALS AND METHODS

This study included 28 patients with unruptured intracranial vertebrobasilar dissecting aneurysms with brain stem compression treated from January 2009 to December 2017. Treatment methods were observation (n = 6), stent-assisted coil embolization (n = 9), parent artery occlusion (n = 6), and flow diversion (n = 7). The data of baseline characteristics, change of aneurysm size, retreatment rate, stroke occurrence, and alteration of the mRS score were obtained from retrospective chart review.

RESULTS

The initial size of dissecting aneurysms was largest in the flow diversion group (22.5 ± 7.7 mm), followed by parent artery occlusion (20.3 ± 8.4 mm), stent-assisted coil embolization (11.7 ± 2.2 mm), and observation (17.8 ± 5.5 mm; P = .01) groups. The reduction rate of aneurysm size was highest in the parent artery occlusion group (26.7 ± 32.1%), followed by flow diversion (14.1% ± 28.7%), stent-assisted coil embolization (-17.9 ± 30.3%), and observation (-31.5 ± 30.8%; P = .007) groups. Additional treatment was needed in the observation (4/6, 66.7%) and stent-assisted coil embolization (3/9, 33.3%; P = .017) groups. Improvement of the mRS score on follow-up was observed in the flow diversion (6/7, 85.7%) and parent artery occlusion (4/6, 66.7%) groups but not in the stent-assisted coil embolization and observation groups. A worsened mRS score was most common in the observation group (4/6, 66.7%), followed by stent-assisted coil embolization (3/9, 33.3%), parent artery occlusion (2/6, 33.3%), and flow diversion (0/7, 0%) groups.

CONCLUSIONS

When treating intracranial vertebrobasilar dissecting aneurysms with brain stem compression, parent artery occlusion and flow diversion should be considered to reduce aneurysm size and improve the mRS score.

3334Updated meta-analysis of biodegradable polymer drug-eluting stent versus second-generation durable polymer drug-eluting stent implantations

Background

Data regarding clinical outcomes of biodegradable polymer drug-eluting stent (BP-DES) versus second-generation durable polymer drug-eluting stent (DP-DES) in patients undergoing percutaneous coronary intervention (PCI) are inconclusive.

Purpose

We aimed to perform a meta-analysis to investigate the clinical outcomes of BP-DES compared with second-generation DP-DES in patients who have undergone PCI.

Methods

We searched PubMed, MEDLINE, EMBASE, and Cochrane databases through January 2019 for randomized controlled trials comparing BP-DES with second-generation DP-DES in patients treated with PCI. All-cause death, cardiac death, myocardial infarction (MI), target vessel revascularization (TVR), target lesion revascularization (TLR), definite/probable stent thrombosis (ST) were compared between the groups. Additionally, a landmark analysis with the landmark set at 1 year and a subgroup analysis according to stent characteristics were performed.

Results

Data from 23 trials including 28802 randomized patients were analyzed. At a median follow up of 3.1 years, no significant differences were found in terms of all-cause death (odds ratio [OR] 1.05, 95% confidence interval [CI] 0.95–1.16), cardiac death (OR 1.01, 95% CI 0.87–1.17), MI (OR 0.92, 95% CI 0.82–1.03), TVR (OR 0.97, 95% CI 0.86–1.11), TLR (OR 0.97, 95% CI 0.85–1.11), and definite/probable ST (OR 0.86, 95% CI 0.70–1.07) between the groups. Landmark analysis showed that there were similar risks in all-cause death (OR 1.04, 95% CI 0.93–1.17), cardiac death (OR 1.11, 95% CI 0.92–1.36), MI (OR 0.94, 95% CI 0.79–1.13), TVR (OR 0.95, 95% CI 0.73–1.23), TLR (OR 1.00, 95% CI 0.80–1.24), and definite/probable ST (OR 0.92, 95% CI 0.67–1.28) between the groups. The similar tendency of any study endpoints between the groups was consistent in the subgroup, including stent platform (stainless steel vs. alloy), the drug coating distribution (abluminal vs. circumferential), the polymer degradation period (<6 months vs. >6 months), or the drug release duration (<6 months vs. >6 months) of BP-DES, or the DAPT duration (≥6 months vs. ≥12 months). However, the uses of BP-DES with sirolimus-eluting (OR 0.84, 95% CI 0.72–0.98) or ultrathin strut (defined as <70μm; OR 0.81, 95% CI 0.68–0.97) were predictive for lower risk of MI.

Clinical outcomes

Conclusions

In our updated meta-analysis, BP-DES implantation was associated with comparable clinical outcomes compared with second-generation DP-DES implantation. However, PCI with ultrathin biodegradable polymer sirolimus-eluting stent could reduce the risk of MI.

P2799Long-term outcomes after percutaneous coronary intervention with biodegradable polymer drug-eluting stent versus second-generation durable polymer drug-eluting stent: evidence from a meta-analysis

Background

The true benefit of biodegradable polymer drug-eluting stent (BP-DES) over second-generation durable polymer drug-eluting stent (DP-DES) expected to be represented during late period of follow-up after percutaneous coronary intervention (PCI), but prior meta-analysis only evaluated short-term outcomes.

Purpose

We aimed to compare the long-term clinical outcomes after PCI with BP-DES versus second-generation DP-DES by a meta-analysis of randomized controlled trials.

Methods

Randomized controlled trials comparing BP-DES with second-generation DP-DES implantations were searched through PubMed, MEDLINE, EMBASE, and Cochrane databases. All-cause death, cardiac death, myocardial infarction (MI), target vessel revascularization (TVR), target lesion revascularization (TLR), and definite/probable stent thrombosis (ST) were compared between the groups. In addition, a landmark analysis with the landmark set at 1-year and a subgroup analysis based on stent characteristics were performed.

Results

Fifteen trials that included a total of 21311 randomized patients with at least 2 years follow-up were analyzed. At a median follow-up of 4.2 years, no significant differences in the risks of all-cause death (odds ratio [OR] 1.03, 95% confidence interval [CI] 0.94–1.14), cardiac death (OR 1.03, 95% CI 0.88–1.20), MI (OR 0.90, 95% CI 0.79–1.01), TVR (OR 0.96, 95% CI 0.82–1.12), TLR (OR 0.97, 95% CI 0.85–1.11), and definite/probable ST (OR 0.84, 95% CI 0.67–1.05) were found between the groups. In the 1-year landmark analysis, the rates of all-cause death (OR 1.04, 95% CI 0.93–1.17), cardiac death (OR 1.11, 95% CI 0.92–1.36), MI (OR 0.94, 95% CI 0.79–1.13), TVR (OR 0.95, 95% CI 0.73–1.23), TLR (OR 1.00, 95% CI 0.80–1.24), and definite/probable ST (OR 0.94, 95% CI 0.67–1.31) were similar between the groups. There were comparable rates of any study endpoints between the groups regardless of stent platform (stainless steel vs. alloy), the polymer degradation period (<6 months vs. >6 months) or the drug release duration (<6 months vs. >6 months) of BP-DES, or the DAPT duration (≥6 months vs. ≥12 months). However, the use of BP-DES with sirolimus eluting (OR 0.82, 95% CI 0.70–0.97), circumferential drug distribution (OR 0.79, 95% CI 0.65–0.96), thin strut (defined as <100μm; OR 0.83, 95% CI 0.70–0.97), or ultrathin strut (defined as <70μm; OR 0.78, 95% CI 0.64–0.94) were associated with lower rates of MI than did second-generation DP-DES. Moreover, BP-DES with circumferential drug distribution (OR 0.82, 95% CI 0.69–0.98) was predictive for reduced rates of TVR.

Clinical outcomes

Conclusions

In this meta-analysis, long-term clinical outcomes were equivalent between BP-DES and second-generation DP-DES implantations. However, among BP-DESs, the improved risks of MI in those with sirolimus eluting, circumferential drug distribution, thin strut, or ultrathin strut and decreased rates of TVR in those with circumferential drug distribution were noted.

Proposal of a New TNM Classification for Gastric Cancer: Focusing on pN3b and Cytology-Positive (CY1) Disease

Purpose

Gastric cancer with lymph node metastasis (LNM) more than 15 (N3b) was defined as stage IV until the 6th AJCC system. However, it has been reclassified as a localized disease (stage IIb or III) since the 7th system. The aim of this study is to demonstrate that the survival of N3b is comparable to cytology-only positive (CY1-only) stage IV and to propose a new TNM system interpreting N3b as an eligibility criterion for receiving more intensive chemotherapy regimens.

Materials and Methods

1,430 patients who underwent gastric cancer surgery at Seoul National University Hospital from 2007 to 2012 were retrospectively analyzed. The 5-year survival rate (5YSR) and 3-year recurrence-free survival (RFS) were evaluated according to the 7th and 8th systems, as well as a new categorization based on N-classification; N0-2 (LNM<7), N3a (LNM 7–15), or N3b (LNM>15).

Results

The survival of N3b is comparable to that of CY1-only stage IV (log rank test, P=0.671) and is distinct from that of grossly stage IV (log rank test, P<0.001). The survival of the remaining stage IIIc (T4bN3a) was comparable to those of N3b and CY1-only stage IV. Most N3b patients had significantly shorter 3-year RFS and mean RFS than those with IIb–IIIc, as if N3b itself was a higher TNM stage.

Conclusions

In terms of survival, T4bN3a, N3b, and CY1-only stage IV were unified as stage IVa, while grossly stage IV was defined as stage IVb. N3b can be regarded as an eligibility criterion for undergoing more intensive chemotherapy regimens.

Fuel-Composition Dependent Reactor Antineutrino Yield at RENO

We report a fuel-dependent reactor electron antineutrino (ν[over ¯]_{e}) yield using six 2.8 GW_{th} reactors in the Hanbit nuclear power plant complex, Yonggwang, Korea. The analysis uses 850 666 ν[over ¯]_{e} candidate events with a background fraction of 2.0% acquired through inverse beta decay (IBD) interactions in the near detector for 1807.9 live days from August 2011 to February 2018. Based on multiple fuel cycles, we observe a fuel ^{235}U dependent variation of measured IBD yields with a slope of (1.51±0.23)×10^{-43}  cm^{2}/fission and measure a total average IBD yield of (5.84±0.13)×10^{-43}  cm^{2}/fission. The hypothesis of no fuel-dependent IBD yield is ruled out at 6.6σ. The observed IBD yield variation over ^{235}U isotope fraction does not show significant deviation from the Huber-Mueller (HM) prediction at 1.3 σ. The measured fuel-dependent variation determines IBD yields of (6.15±0.19)×10^{-43} and (4.18±0.26)×10^{-43}  cm^{2}/fission for two dominant fuel isotopes ^{235}U and ^{239}Pu, respectively. The measured IBD yield per ^{235}U fission shows the largest deficit relative to the HM prediction. Reevaluation of the ^{235}U IBD yield per fission may mostly solve the reactor antineutrino anomaly (RAA) while ^{239}Pu is not completely ruled out as a possible contributor to the anomaly. We also report a 2.9 σ correlation between the fractional change of the 5 MeV excess and the reactor fuel isotope fraction of ^{235}U.

Intraoperative Management to Prevent Cardiac Collapse in a Patient With a Recurrent, Large-volume Pericardial Effusion and Paroxysmal Atrial Fibrillation During Liver Transplantation: A Case Report

BACKGROUND

Pericardial effusion is a common feature of end-stage liver disease. In this case report we describe the intraoperative management of recurrent pericardial effusion, without re-pericardiocentesis, to prevent circulatory collapse during a critical surgical time-point; that is, during manipulation of the major vessels and graft reperfusion.

METHODS

A 47-year-old woman with hepatitis B was scheduled to undergo deceased donor liver transplantation (LT). A large pericardial effusion was preoperatively identified using transthoracic echocardiography (TTE). The patient also had paroxysmal atrial fibrillation. Two days before surgery, preemptive pericardiocentesis was performed and the 1150-mL effusion was drained. Intraoperatively, recurrence of the large pericardial effusion was identified using transesophageal echocardiography (TEE). During inferior vena cava manipulation, the surgeon consulted the anesthesiologist to evaluate the hemodynamic changes in the patient. After 3 attempts, the transplant team was able to determine the most appropriate anastomosis site, defined as that with the least impact on cardiac function. To prevent the development of severe postreperfusion syndrome, 10% MgSO₄ (2 g) was gradually infused 20 minutes before portal vein declamping, and immediately before graft reperfusion a 100-μg bolus of epinephrine was administered.

RESULTS

During graft reperfusion, there was no evidence of heart chamber collapse or flow disturbance, as seen on the TEE findings. Postoperatively, the patient recovered completely and was discharged from the hospital. Six months after surgery, there was no sign of pericardial effusion on follow-up TTE.

CONCLUSION

Our intraoperative strategy may prevent cardiac collapse in patients with pericardial effusion detected during LT. Intraoperative TEE plays an important role in guiding hemodynamic management.

Regio-regular alternating diketopyrrolopyrrole-based D1–A–D2–A terpolymers for the enhanced performance of polymer solar cells

We designed and synthesized regio-regular alternating diketopyrrolopyrrole (DPP)-based D₁–A–D₂–A terpolymers (PDPPF2T2DPP-T2, PDPPF2T2DPP-TVT, and PDPPF2T2DPP-DTT) using a primary donor (D₁) [3,3′-difluoro-2,2′-bithiophene (F2T2)] and a secondary donor (D₂) [2,2′-bithiophene (T2), (E)-1,2-di(thiophen-2-yl)ethene (TVT), or dithieno[3,2-b:2′,3′-d]thiophene (DTT)]. A PDPP2DT-F2T2 D–A polymer was synthesized as well to compare optical, electronic, and photovoltaic properties. The absorption peaks of the terpolymers (PDPPF2T2DPP-T2, PDPPF2T2DPP-TVT, and PDPPF2T2DPP-DTT) were longer (λ_max = 801–810 nm) than the peak of the PDPP2DT-F2T2 polymer (λ_max = 799 nm), which is associated with the high-lying HOMO levels of the terpolymers (−5.08 to −5.13 eV) compared with the level of the PDPP2DT-F2T2 polymer (−5.38 eV). The photovoltaic properties of these DPP-based polymers were investigated under simulated AM 1.5G sunlight (100 mW cm⁻²) with a conventional structure (ITO/PEDOT:PSS/polymer:PC₇₁BM/Al). The open-circuit voltages (V_oc) of photovoltaic devices containing the terpolymers were slightly lower (0.68–0.70 V) than the V_oc of the device containing the PDPP2DT-F2T2 polymer (0.79 V). The short-circuit current (J_sc) of the PDPPF2T2DPP-DTT device was significantly improved (14.14 mA cm⁻²) compared with that of the PDPP2DT-F2T2 device (8.29 mA cm⁻²). As a result, the power conversion efficiency (PCE) of the PDPPF2T2DPP-DTT device (6.35%) was increased by 33% compared with that of the simple D–A-type PDPP2DT-F2T2 device (4.78%). The highest J_sc and PCE values (the PDPPF2T2DPP-DTT device) were attributed to an optimal nanoscopically mixed morphology and strong interchain packing with a high face-on orientation in the blend film state. The study demonstrated that our strategy of using multiple donors in a regio-regular alternating fashion could fine-tune the optical, electronic, and morphological properties of D–A-type polymers, enhancing the performance of polymer solar cells.

We designed and synthesized regio-regular alternating diketopyrrolopyrrole (DPP)-based D₁–A–D₂–A terpolymers (PDPPF2T2DPP-T2, PDPPF2T2DPP-TVT, and PDPPF2T2DPP-DTT) for use in polymer solar cells.

Immunomodulatory Effects of Placenta-derived Mesenchymal Stem Cells on T Cells by Regulation of FoxP3 Expression

The immunomodulatory effects of mesenchymal stem cells (MSCs) are an important mediator of their therapeutic effects in stem cell therapy and regenerative medicine. The regulation mechanism of MSCs is orchestrated by several factors in both intrinsic and extrinsic events. Recent studies have shown that the dynamic expression of cytokines secreted from MSCs control T cell function and maturation by regulating the expression of FoxP3, which figures prominently in T cell differentiation. However, there is no evidence that placenta-derived mesenchymal stem cells (PD-MSCs) have strong immunomodulatory effects on T cell function and maturation via FoxP3 expression. Therefore, we compared the expression of FoxP3 in activated T cells isolated from peripheral blood and co-cultured with PD-MSCs or bone marrow-derived mesenchymal stem cells (BM-MSCs) and analyzed their effect on T cell proliferation and cytokine profiles. Additionally, we verified the immunomodulatory function of PD-MSCs by siRNA-mediated silencing of FoxP3. MSCs, including PD-MSCs and BM-MSCs, promoted differentiation of naive peripheral blood T cells into CD4+CD25+FoxP3+ regulatory T (Treg) cells. Intriguingly, the population of CD4+CD25+FoxP3+ Treg cells co-cultured with PD-MSCs was significantly expanded in comparison to those co-cultured with BM-MSCs or WI38 cells (p＜0.05, p＜0.001). Dynamic expression patterns of several cytokines, including anti- and pro-inflammatory cytokines and members of the transforming growth factor-beta (TGF-β) family secreted from PD-MSCs according to FoxP3 expression were observed. The results suggest that PD-MSCs have an immunomodulatory effect on T cells by regulating FoxP3 expression.