Impact of Magnetic Field Configuration on Heat Transport in Stellarators and Heliotrons

We assess the magnetic field configuration in modern fusion devices by comparing experiments with the same heating power, between a stellarator and a heliotron. The key role of turbulence is evident in the optimized stellarator, while neoclassical processes largely determine the transport in the heliotron device. Gyrokinetic simulations elucidate the underlying mechanisms promoting stronger ion scale turbulence in the stellarator. Similar plasma performances in these experiments suggests that neoclassical and turbulent transport should both be optimized in next step reactor designs.

Hybridization of Bogoliubov Quasiparticles between Adjacent CuO_{2} Layers in the Triple-Layer Cuprate Bi_{2}Sr_{2}Ca_{2}Cu_{3}O_{10+δ} Studied by Angle-Resolved Photoemission Spectroscopy

Hybridization of Bogoliubov quasiparticles (BQPs) between the CuO_{2} layers in the triple-layer cuprate high-temperature superconductor Bi_{2}Sr_{2}Cu_{2}Cu_{3}O_{10+δ} is studied by angle-resolved photoemission spectroscopy (ARPES). In the superconducting state, an anticrossing gap opens between the outer- and inner-BQP bands, which we attribute primarily to interlayer single-particle hopping with possible contributions from interlayer Cooper pairing. We find that the d-wave superconducting gap of both BQP bands smoothly develops with momentum without an abrupt jump in contrast to a previous ARPES study. Hybridization between the BQPs also gradually increases in going from the off nodal to the antinodal region, which is explained by the momentum dependence of the interlayer single-particle hopping. As possible mechanisms for the enhancement of the superconducting transition temperature, the hybridization between the BQPs as well as the combination of phonon modes of the triple CuO_{2} layers and spin fluctuations represented by a four-well model are discussed.

Association between myocardial wall thickness and left ventricular functional recovery after catheter ablation of atrial fibrillation in patients with reduced ejection fraction

Background

Catheter ablation of atrial fibrillation (AFCA) is an effective treatment to develop left ventricular (LV) functional recovery. However, the degree of recovery differs between individuals due to the different extent of myocardial fibrosis and scarring.

Purpose

To examine whether pre-ablation LV wall thickness (WT) and its regional heterogeneity predict LV functional recovery after AFCA in patients with LV systolic dysfunction.

Methods

Of 3682 consecutive patients who underwent first-time AFCA between January 2012 and September 2020 in our institution, 174 (age, 63±10 years; male, 83%; ischemic cardiomyopathy, 14%) with a baseline LV ejection fraction (LVEF) of <40% were retrospectively evaluated. They were subjected to 256-slice MDCT scanning at baseline and 3 months after AFCA. Baseline WT was evaluated by 16-segment model. Mean and standard deviation (SD) of 16 regional WT were calculated in both end-systolic and end-diastolic phase.

Results

LVEF significantly improved from 30±7% to 57±17% (p<0.001) after AFCA. Increase in LVEF (delta-LVEF) was positively correlated with baseline end-diastolic WT (r=0.31, p<0.001) and negatively correlated with SD of end-systolic WT (r=−0.21, p=0.007). Independent of WT measurements, delta-LVEF was negatively correlated with LV end-diastolic volume (r=−0.42, p<0.001). We created a scoring system to predict the degree of wall motion recovery using the median value of the 3 variables; assigned 1 point each for end-diastolic WT >7.4mm, SD of end-systolic WT <1.61mm, and LV end-diastolic volume <125ml. The model successfully predicted improvement in LVEF after AFCA (0 point (N=13) vs. 1 point (N=72) vs. 2–3 point (N=89), 11±16% vs. 20±17% vs. 33±12%, p<0.001).

Conclusion

Myocardial WT and its regional heterogeneity as well as LV end-diastolic volume predicted functional recovery after AFCA in patients with reduced LVEF.

Funding Acknowledgement

Type of funding sources: None.

Effects of left ventricular mass index on computed tomography derived fractional flow reserve in significant obstructive coronary artery disease

Background

In significant obstructive coronary artery disease (SOCAD), a mismatched assessment of the severity of coronary artery stenosis may occur between invasive coronary angiography and computed tomography (CT) derived fractional flow reserve (FFRCT). The exact mechanisms of unexpected underestimation of FFRCT remain unknown.

Purpose

The aims of this study are (1) to clarify the mechanisms of underestimation on FFRCT; and (2) to identify the predictive factors of FFRCT underestimation above the value of 0.80 in SOCAD vessels.

Methods

A total of 1160 outpatients who underwent CT angiography (CTA) with FFRCT analysis for suspected coronary artery disease (CAD) between January 2017 and June 2020 were evaluated. Among them, 141 consecutive patients who had both CTA coupled to FFRCT analysis and invasive angiogram showing >75% coronary stenosis were included for analysis. Vessels were divided into two groups according to FFRCT at the distal vessel: FFRCT >0.80 (n=12) and FFRCT ≤0.80 (n=153). Vessel-related parameters, including vessel morphology (vessel length and lumen volume) and plaque components (non-calcified plaque volume and calcified plaque volume) and left ventricular (LV) myocardial-related parameters, including LV wall thickness at each site of the myocardium, and LV mass were evaluated semi-automatically.

Results

Vessel morphology and plaque components did not differ between FFRCT >0.80 and ≤0.80, whereas LV wall thickness (average; 10.7±2.7 vs. 8.4±1.6 mm, and maximal; 13.5±3.0 vs. 10.6±1.8 mm, all p value <0.001), LV mass (136.4±38.4 vs. 98.8±26.8 g, p<0.001), and LV mass index (73.8±22.6 vs. 51.8±12.2 g/m2, p<0.001) were significantly higher in FFRCT >0.80. Next, we investigated the parameters that correlated with FFRCT. Of all, vessel morphology and plaque components were not related to FFRCT, whereas maximal LV wall thickness, r=0.24, p=0.01; LV mass, r=0.19. p=0.04; and LV mass index, r=0.30, p=0.001) correlated with FFRCT. In the vessels showing FFRCT >0.80, only LV mass (r=0.84, p=0.005) and LV mass index (r=0.67, p=0.047) correlated with FFRCT. (Figure 1). LV mass index was the strongest predictor of a distal FFRCT of >0.80 with the area under curve (AUC) 0.81, 95% CI 0.62 – 1.00, P<0.0001 and an optimal cut-off value of 66.5 g/m2 sensitivity 77.8%, specificity 89.6% (Figure 2).

Conclusions

FFRCT is affected not by vessel-related parameters but LV myocardial-related parameters in SOCAD. The presence of an excessive LV mass is a major predictor of underestimation of FFRCT in SOCAD vessels. LV myocardial-related parameters should be considered when interpreting numerical values of FFRCT to avoid the possibility of overlooked SOCAD.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Impact of vascular morphology and plaque characteristics on computed tomography derived fractional flow reserve in early stage coronary artery disease

Background

FFRCT gradually decreases from the proximal to the distal part of a vessel and reach the pathological threshold for significant ischemia even in the absence of obstructive coronary artery disease (CAD). The exact mechanisms of such gradual FFRCT decline remain unknown.

Purpose

The aims of this study are (1) to clarify the mechanisms of the gradual decline of computed tomography (CT) derived fractional flow reserve (FFRCT); and (2) to identify the predictive factors of an FFRCT decline below the pathological value of 0.80 in no apparent CAD vessels.

Methods

A total of 1058 outpatients with suspected CAD and who underwent CT angiography (CTA) with FFRCT analysis between January 2017 and December 2019 were evaluated. Among them, 150 consecutive patients who had both a CTA coupled to an FFRCT analysis and an invasive angiogram showing <25% coronary stenosis were included for analysis. Vessels were divided into two groups according to FFRCT at the distal vessel: FFRCT >0.80 (n=317) and FFRCT ≤0.80 (n=114). ΔFFRCT was defined as the magnitude of the change in FFRCT from the proximal to the distal vessel. Plaque characterization and vessel morphology measurements were performed semi-automatically. Vessel constituents were characterized based on Hounsfield units (HU) into lumen volume (<−50 HU), non-calcified plaque (NCP) (−50–150 HU), and calcified plaque (>150 HU).

Results

FFRCT decreased continuously from the proximal to distal across the three major vessels in both FFRCT>0.80 and FFRCT ≤0.80 groups (Figure 1). Compared to FFRCT>0.80 group, NCP volume was significantly higher in all three major vessels in FFRCT ≤0.80 group (210.2±83.6 mm3 vs. 140.9±139.3 mm3 for the RCA, p=0.01; 177.5±150.2 mm3 vs. 133.2±112.2 mm3 for the LAD, p=0.04; 127.6±91.5 mm3 vs. 58.7±57.7 mm3 for the LCX, p<0.01). Next, we investigated the vessel parameters that correlated with ΔFFRCT. ΔFFRCT was correlated with lumen volume in FFRCT>0.80 group (r=−0.24, p<0.0001), whereas ΔFFRCT was correlated with NCP volume in FFRCT ≤0.80 group (r=0.42, p<0.001) (Figure 2). An NCP volume above 44.8 mm3 was the strongest predictor of distal FFRCT of ≤0.80 (area under the curve 0.69, p<0.0001, sensitivity 95%, specificity 39%).

Conclusions

FFRCT is affected by vascular morphology and plaque characteristics even in the early stage of coronary artery disease. Our study highlights that subclinical coronary artery disease strongly influences FFRCT by effects unrelated to coronary stenosis. The presence of NCP is a major predictor of the gradual decrease of FFRCT toward pathological values. Anatomical findings as vessel morphology and plaque characteristics should be taken into consideration when interpreting numerical values of FFRCT to avoid unnecessary referrals for invasive coronary angiography or percutaneous coronary intervention.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Preoperative Pre-albumin Concentration as a Predictor of Short-term Outcomes in Elderly Patients With Colorectal Cancer

BACKGROUND/AIM

Population aging results in increasing numbers of elderly persons undergoing surgery for colorectal cancer. We sought to identify objective preoperative indicators of outcomes, with a view toward development of safe, effective treatments for such patients.

PATIENTS AND METHODS

The study included 99 patients aged 80 years or more, who were treated surgically for stage I- III colorectal cancer. Preoperative nutritional status was compared retrospectively between those who suffered postoperative complications (n=40) and those who did not (n=59).

RESULTS

Univariate analysis revealed low prealbumin (PreAlb) concentration (p=0.032) and low platelet-to-lymphocyte ratio (p=0.116) as risk factors for postoperative complications. Multivariate analysis showed preoperative PreAlb concentration to be an independent risk factor (OR=0.884; 95% confidence interval=0.791-0.989; p=0.024) associated with postoperative length of hospital stay (coef.=-0.336, p=0.002).

CONCLUSION

PreAlb, a rapid turnover protein, shows promise as a simple predictor of postoperative complications in elderly patients treated for colorectal surgery.

Cost effectiveness of romosozumab versus teriparatide for severe postmenopausal osteoporosis in Japan

This study assessed the cost effectiveness of romosozumab versus teriparatide, both sequenced to alendronate, for the treatment of severe postmenopausal osteoporosis in Japan, using bone mineral density (BMD) efficacy data. Results show that romosozumab/alendronate produces greater health benefits at a lower cost than teriparatide/alendronate.

INTRODUCTION

This study aims to assess the cost effectiveness of romosozumab versus teriparatide, both sequenced to alendronate, for the treatment of severe postmenopausal osteoporosis in Japanese women previously treated with bisphosphonates.

METHODS

A Markov model was used to assess the relative cost effectiveness of 1 year of romosozumab versus 2 years of teriparatide, both sequenced to alendronate for a total treatment duration of 5 years. Outcomes for a cohort of women with a mean age of 78 years, a T-score ≤-2.5 and a previous fragility fracture were simulated over a lifetime horizon. The analysis was conducted from the perspective of the Japanese healthcare system and used a discount rate of 2% per annum. To inform relative fracture incidence, the bone mineral density (BMD) advantage of romosozumab over teriparatide was translated into relative risks of fracture, using relationships provided by a meta-regression of osteoporosis therapy trials. Outcomes were assessed in terms of lifetime costs (2020 US dollars) and quality-adjusted life years (QALYs).

RESULTS

Base case results showed that, compared with teriparatide/alendronate, romosozumab/alendronate reduced costs by $5134 per patient and yielded 0.045 additional QALYs. Scenario analyses and probabilistic sensitivity analysis confirmed that results are robust to uncertainty in model assumptions and inputs.

CONCLUSION

Results show that romosozumab/alendronate produces greater health benefits at a lower total cost than teriparatide/alendronate.

Risk factors for thrombocytopenia and analysis of time to platelet transfusion after azacitidine treatment

The use of azacitidine (AZA) has been known to lead to a high incidence of hematotoxic adverse events. The aims of this study were to identify the risk factors for thrombocytopenia after the administration of AZA and to analyze time to the initial platelet transfusion. Sixty-two patients with myelodysplastic syndrome (MDS), who were treated with AZA in Gifu Municipal Hospital between March 2012 and June 2020, were included in this study. The risk factors for thrombocytopenia were identified using univariate analysis of patient characteristics, disease type, and laboratory values immediately before the start of treatment. Variables with p<0.2 identified in the univariate analysis were used as independent variables in the multivariate analysis. This analysis identified "creatinine clearance (CCr) <60 mL/min" as a significant factor (odds ratio, 4.790; 95% confidence interval [CI], 1.380-16.70; p=0.014). Subsequently, time in days to the initial platelet transfusion after the initial administration of AZA was analyzed using the log-rank test. The overall median time in days to platelet transfusion was 370 days. The log-rank test was used to determine the influence of patient characteristics, disease type, and laboratory values immediately before the start of treatment. The subsequent Cox proportional hazard regression analysis using variables with p<0.2 as independent variables identified "hemoglobin (Hb) <8.0 g/dL" as a significant factor (hazard ratio, 2.143; 95% CI, 1.001-4.573; p=0.048). The results of this study led to the following clinical implications: first, patients with CCr of <60 mL/min at the start of treatment should be treated with caution due to the risk of thrombocytopenia. Second, patients with Hb of <8.0 g/dL at the start of treatment may require platelet transfusion in the early stage of treatment.

P–146 Differential impact of three embryo culture media for IVF on in vitro development and perinatal outcome: a single-center RCT

Study question

This report provides updated data from an RCT determining which embryo culture medium yields optimal IVF outcomes.

Summary answer

Embryo culture systems used for IVF differentially affected preimplantation development and resultant obstetric and perinatal outcomes, including birthweights of live-born singletons.

What is known already

Currently, multiple embryo culture medium systems are in use for IVF, raising questions regarding which is optimal. However, the ability of a medium to yield preimplantation embryos is not necessarily indicative of embryo viability. For example, supplementation of medium with serum was commonly used to increase animal blastocyst yields, but this impaired embryonic, fetal, and offspring health. In humans, medium composition and culture duration can influence IVF efficacy and offspring phenotype. Given the importance of culture systems in determining clinical outcomes, existing data regarding differential culture system impacts are insufficient and additional well-designed studies are required.

Study design, size, duration

Between February 2016 and August 2017, 795 couples undergoing their first autologous clinical IVF cycle and freeze-all strategy were recruited. Participants were randomized via computer-generated tables into three groups. Following standard oocyte retrieval and IVF/ICSI procedures, embryos were cultured using three different culture media, G1 Plus/G2 Plus (G1/G2; Vitrolife), Global Total (GT; LifeGlobal), or Sequential Cleav/Sequential Blast (SC/SB; Origio). Thirty-eight patients exhibiting no 2PN oocytes following insemination or those undergoing fresh embryo transfers were excluded.

Participants/materials, setting, methods

For patients yielding a single good-quality cleavage-stage (day–2 or day–3) embryo, that cleavage-stage embryo was vitrified. For patients yielding two or more good-quality cleavage-stage embryos, two or less good-quality cleavage-stage embryos were vitrified. The culture period of the remaining embryos was extended, and all good-quality blastocyst-stage (day–5 or day–6) embryos were vitrified. This report presents data for vitrified embryo transfer performed until the end of December 2020.

Main results and the role of chance

The mean per-cycle vitrified embryo yield (± SD) was comparable between groups for cleavage-stage embryos, but significantly different for blastocyst-stage embryos (G1/G2: 1.69 ± 2.2, GT: 2.53 ± 3.01, SC/SB: 2.04 ± 2.42; P = 0.001). Following vitrified cleavage- or blastocyst-stage embryo transfers, biochemical pregnancy rates were significantly different between groups (G1/G2: 55.6%, GT: 59.1%, SC/SB: 46.2%; P = 0.011). Furthermore, a between-group trend towards different live birth rates was observed (G1/G2: 41.7%, GT: 42.1%, SC/SB: 33.1%; P = 0.063). Of 382 live births, data for first-borns (n = 323; 295 singletons and 14 twin-pairs) are reported here. Perinatal data did not differ significantly between groups for both cleavage- and blastocyst-stage embryo transfers, including gestational age- and gender-adjusted singleton birthweight (z-score). Following multiple linear regression (including selected covariates), adjusted mean singleton birthweights were significantly lower in the G1/G2 and GT groups than in the SC/SB group (by 131 g; P = 0.011 and 110 g; P = 0.032, respectively) and tended to be lower for cleavage-stage embryo transfers than for blastocyst-stage embryo transfers (by 102 g; P = 0.053).

Limitations, reasons for caution

A larger cohort size and longer-term follow-up are required to verify and further elucidate the impact of embryo culture methods on child health. Such studies will raise awareness regarding the sensitivity of in vitro-cultured human embryos to their environment, ultimately resulting in practices that decrease IVF risks to offspring.

Wider implications of the findings: Pregnancy outcome of the medium yielding fewer blastocysts was comparable or superior to that of other media, highlighting the importance of differentiating between the ability to support preimplantation development versus the ability to yield viable embryos. Embryo culture medium had a greater impact than embryo transfer stage on live birthweight.

Trial registration number

UMIN000020910

P–221 Prospective randomized sibling study on gamete preparation, insemination and subsequent culture of human oocytes in a time-lapse system using media systems with and without antioxidants

Study question

Does the addition of antioxidants for gamete preparation, insemination and embryo culture lead to differences in embryo development and clinical outcome

Summary answer

Using an antioxidant-containing media system for sperm preparation, insemination and embryo culture imparts significantly higher good-quality blastocyst rates and improved clinical outcome in elderly patients.

What is known already

A previous study showed that adding combined antioxidants for sequential embryo culture in conventional incubators (interrupted culture) improves embryo viability and clinical outcome, especially for elderly patients. Here we investigated the combined effect of three antioxidants Acetyl-L-Carnitine (10 µM), N-Acetyl-L-Cysteine (10 µM), and α-Lipoic Acid (5 µM) during sperm preparation, insemination, and time-lapse culture in a single step medium on human embryo development and clinical outcome.

Study design, size, duration

Prospective randomized single center study including 143 couples for IVF/ICSI between August 2018 and December 2019. Inclusion required at least eight cumulus-oocyte-complexes (COCs) after retrieval. Cycles involving PGT, split IVF/ICSI, and surgically retrieved sperm were excluded. Immediately after retrieval oocytes were randomly distributed to a study or control media system with or without antioxidants (Vitrolife). Similarly, ejaculates were split and prepared with and without antioxidants.

Participants/materials, setting, methods

Sibling oocytes were inseminated in the respective group with accordingly prepared sperm. Single step embryo culture was conducted in medium with (Gx-TL) and without (G-TL) antioxidants in the EmbryoScope+. Embryo quality and clinical outcome were assessed in relation to maternal age (&lt;35/&gt;35 years). Good-quality embryos on day 3 were defined as 8- to 10-cells with even cells and low fragmentation; good-quality blastocysts as &gt; 3BB. Clinical outcome was assessed after single vitrified blastocyst transfer (SVBT).

Main results and the role of chance

From 143 participants (female age, 34.7±3.2 years), a total of 2424 COCs were collected; 1180 COCs/916 metaphase-II (MII) oocytes were allocated to Gx-TL media and 1244 COCs/981 MII oocytes to G-TL media. Age-related analysis in Gx-TL compared with G-TL in relation to allocated MII oocytes revealed a trend for higher fertilization rates in Gx-TL for both age groups (&lt;35: 72.1% vs. 66.9%; &gt;35: 70.7% vs. 64.9%, P &lt; 0.1). Good-quality day 3 embryo development/MII oocytes was higher, albeit not significant, in the elderly patients in Gx-TL (&lt;35: 35.9% vs. 34.4%; &gt;35: 31.1% vs. 27.9%). Overall day 5/6 blastocyst rate was similar for both media (&lt;35: 48.2% vs. 49.9%; &gt;35: 42.3% vs. 39.5%). Day 5/6 GQB rate was comparable for younger patients (&lt;35: 23.8% for Gx-TL vs. 26.0% for G-TL) but significantly higher in Gx-TL in elderly patients (&gt;35: 20.7% vs. 14.4%; P &lt; 0.05). A total of 200 SVBT were performed; 99 in the Gx-TL- and 101 in the G-TL-arm. We noted almost similar implantation and ongoing pregnancy rates between Gx-TL vs G-TL in the younger (&lt;35) age group (50.0% vs. 55.4%; 50.0% vs. 55.6%) but higher albeit not significant rates for Gx-TL in older (&gt;35) patients (44.1% vs. 33.3%; 44.1% vs. 33.3%).

Limitations, reasons for caution

In almost 95% of the cycles, oocytes were inseminated by ICSI; thus results may not equally apply for cycles with IVF. The use of a closed time-lapse system may have prevented from some environmental oxidative stress. Therefore results may come out different with a similar study using standard incubation.

Wider implications of the findings: Supplementation of antioxidants to media for gamete isolation and preparation, as well as subsequent single step time-lapse culture may improve GQE/B rates and clinical outcomes in certain age groups, plausibly through the reduction of oxidative stress. Further studies in selected sub-groups (severe OAT syndrome / testicular cases) may be indicated.

Trial registration number

UMIN000034482

Gefitinib induction followed by chemoradiotherapy in EGFR-mutant, locally advanced non-small-cell lung cancer: LOGIK0902/OLCSG0905 phase II study

Background

The role of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) induction coupled with standard concurrent chemoradiotherapy (CRT) is unclear in unresectable, stage III, EGFR-mutant non-small-cell lung cancer (NSCLC). Therefore, a phase II trial was conducted to evaluate the efficacy and safety of gefitinib induction followed by CRT in this disease setting.

Patients and methods

Patients with unresectable, EGFR-mutant, stage III NSCLC were administered gefitinib monotherapy (250 mg/day) for 8 weeks. Subsequently, patients without disease progression during induction therapy were administered cisplatin and docetaxel (40 mg/m² each) on days 1, 8, 29, and 36 with concurrent radiotherapy at a total dose of 60 Gy. The primary endpoint was the 2-year overall survival (OS) rate, which was hypothesized to reach 85%, with a threshold of the lower limit of 60%.

Results

Twenty patients (median age: 66 years; male/female: 9/11; histology: 20 adenocarcinoma; stage IIIA/IIIB: 9/11; and exon 19/21: 10/10) were enrolled. The 2-year OS rate was 90% (90% confidence interval: 71.4% to 96.8%), indicating that this trial met the primary objective. The overall response rate and 1- and 2-year progression-free survival rates were 85.0%, 58.1%, and 36.9%, respectively. Grade ≥3 adverse events (>10%) included hepatic toxicity during the induction phase and neutropenia and febrile neutropenia in the CRT phase. Radiation pneumonitis grade ≥3 or treatment-related death did not occur.

Conclusions

This is the first prospective study to demonstrate the favorable efficacy and safety of EGFR-TKI induction followed by standard CRT in EGFR-mutant, stage III NSCLC. Further confirmatory studies are needed.

•

This is the first prospective study evaluating gefitinib induction followed by CRT in EGFR-mutated, locally advanced NSCLC.

•

The 2-year OS rate was 90% (90% confidence interval: 71.4% to 96.8%), indicating that this trial met the primary objective.

•

The objective response rate throughout the treatment protocol was 85.0% (17 of 20).

•

The safety findings were consistent with the known safety profiles of all agents administered.

•

Our results might raise a critical point that needs to be evaluated in further studies to improve the cure rate.

A case of bile duct diverticulum with repeated acute cholangitis due to diverticular stone fall

A 34-year-old man presented to the emergency department with a chief complaint of epigastric pain. Endoscopic ultrasound detected a 5 mm stone in the common bile duct. After endoscopic sphincterotomy, the black stones and debris were removed with balloon catheter. Abdominal ultrasonography detected no gallbladder stones; hence, the patient was followed up. However, 3 months later, the patient again developed acute cholangitis caused by common bile duct stones and underwent endoscopic stone removal. Cholangiography under balloon occlusion revealed a left hepatic duct diverticulum with an internal defect. Intraductal ultrasonography showed a hyperechoic lesion with acoustic shadow in the diverticulum, suggesting a stone or debris. Therefore, the patient was considered to have had repeated acute cholangitis because of the presence of falling diverticular stones. The patient underwent left hemihepatectomy plus segmentectomy 1 and cholecystectomy. Histopathologically, it was a true diverticulum without internal epithelial atypia. Many debris were seen in the diverticulum. Gallbladder stones were not observed. Eventually, the patient was discharged from the hospital with no postoperative complications and no recurrence of cholangitis after 20 months.

Absence of microsatellite instability in extramammary Paget's disease

Background

Deficiency of DNA mismatch repair (MMR) induces microsatellite instability (MSI). Pembrolizumab, an antibody targeting PD‐1 (an immune checkpoint inhibitor), is more effective against MMR‐deficient tumours than against MMR‐proficient tumours. The status of MMR is a useful biomarker for predicting the effectiveness of pembrolizumab administration. Although the status of MMR has attracted attention in skin tumours, there are few reports on MSI in extramammary Paget's disease (EMPD).

Objectives

To evaluate the status of MMR in patients with EMPD.

Materials & Methods

One hundred one patients with EMPD were included. MMR status of the genomic DNA of each subject was analysed using Promega panel (approved as a companion diagnostic agent for the administration of pembrolizumab).

Results

MSI testing showed the occurrence rates of MSI‐high (more than two markers are unstable), MSI‐low (one marker is unstable) and MSS (all markers are stable) tumour tissues were 0% (0/101), 1.0% (1/101) and 99.0% (100/101), respectively.

Conclusion

The status of MMR may not be useful for the potential therapeutic application of pembrolizumab.

Multifaceted array-based keloidal gene expression profiling reveals specific MDFI upregulation in keloid lesions

BACKGROUND

Keloid lesions are characterized by mesenchymal cell proliferation and excessive extracellular matrix deposition. Previous microarray analyses have been performed to investigate the mechanism of keloid development. However, the molecular pathology that contributes to keloid development remains obscure.

AIM

To explore the underlying essential molecules of keloids using microarrays.

METHODS

We performed microarray analyses of keloid and nonlesional skin tissues both in vivo and in vitro. Gene expression levels were compared between tissues and cells. Quantitative reverse transcription (qRT)-PCR and immunohistochemical staining were used to determine the expression levels of molecules of interest in keloid tissues.

RESULTS

Several common molecules were upregulated in both keloid tissues and keloid-lesional fibroblasts. PTPRD and NTM were upregulated both in vivo and in vitro. The genes MDFI and ITGA4 were located at the centre of the gene coexpression network analysis using keloid tissues. qRT-PCR revealed significant expression levels of PTPRD and MDFI in keloid tissues. Immunopathological staining revealed that MDFI-positive cells, which have fibroblast characteristics, were located in the keloid-associated lymphoid tissue (KALT) portion of the keloid tissue.

CONCLUSION

Our gene expression profiles of keloids could distinguish the difference between lesional tissue and cultured lesional fibroblasts, and MDFI was found to be commonly expressed in both tissues and cells. Thus, MDFI-positive cells, which were located in the KALT, may play an important role in keloid pathogenesis and thus might be useful for in vitro keloid studies.

W-band millimeter-wave back-scattering system for high wavenumber turbulence measurements in LHD

A 90 GHz W-band millimeter-wave back-scattering system is designed and installed for measuring electron scale turbulence (k_⊥ρ_s ∼ 40). A metal lens relay antenna is used for in-vessel beam focusing, and a beam diameter of less than 40 mm is achieved in the plasma core region. This antenna can be steered at an angle of 159° ± 6°, which almost covers the plasma radius. The estimated size of the scattering volume is ∼105 mm at the edge and 135 mm at the core, respectively. A 60 m corrugated waveguide is used to achieve a low transmission loss of ∼8 dB. A heterodyne detection system for millimeter-wave circuits with probing power modulation can distinguish the scattered signal from background noise.