Electric-Field-Driven Nanosecond Ferroelastic-Domain Switching Dynamics in Epitaxial Pb(Zr,Ti)O_{3} Film

Epitaxial oxide ferroelectric films exhibit emerging phenomena arising from complex domain configurations even at pseudoequilibrium, including the creation of domain states unfavored in nature and abrupt piezoelectric coefficients around morphotropic phase boundaries. The nanometer-sized domain configurations and their domain switching dynamics under external stimuli are directly linked to the ultrafast manipulation of ferroelectric thin films; however, complex domain switching dynamics under homogeneous electric fields has not been fully explored, especially at the nanosecond timescale. This Letter reports the nanosecond dynamics of ferroelastic-domain switching from the 90° to 180° direction using time-resolved x-ray microdiffraction under homogeneous electric fields onto an epitaxial Pb(Zr_{0.35},Ti_{0.65})O_{3} film capacitor. It is found that the application of electric fields induces spatially heterogeneous domain switching processes via intermediate domain structures with rotated polarization vectors. In addition, the domain switching time is shown to be inversely proportional to the magnitude of the applied electric field, and electric fields higher than 480  kV/cm are found to complete the ferroelastic switching within nanoseconds.

Tenofovir alafenamide for hepatitis B virus infection including switching therapy from tenofovir disoproxil fumarate

BACKGROUND AND AIM

Tenofovir alafenamide (TAF) is a new prodrug of tenofovir, enabling treatment of patients with hepatitis B virus (HBV) infection at a lower dose than tenofovir disoproxil fumarate (TDF), via more efficient delivery of tenofovir to the hepatocytes. We compared the efficacy and safety of TDF and TAF and investigated switching from TDF to TAF therapy.

METHODS

Consent for TDF and TAF therapy was obtained from 117 and 67 patients from August 2014 to January 2018. In total, 45 and 14 patients were administered with TDF and TAF, respectively, as naïve therapy, and 36 patients were switched from TDF to TAF. The antiviral effects and renal function safety were assessed.

RESULTS

At week 48, the antiviral effects on patients receiving TDF and TAF as naïve therapy were similar in terms of reduction of HBV DNA (-5.6 ± 1.8 logIU/ml vs -5.0 ± 1.7 log IU/ml; P = 0.34) and hepatitis B surface antigen (-0.29 ± 0.64 logIU/ml vs -0.15 ± 0.42 logIU/ml; P = 0.71) levels. A significant decrease in the estimated glomerular filtration rate (eGFR) was seen at 48-week TDF treatment (-5.34 ± 7.69 ml/min/1.73 m² ; P < 0.001). Switching from TDF to TAF did not increase the HBV DNA or hepatitis B surface antigen at 24 weeks. Although the eGFR worsened during TDF therapy (-7.32 ± 4.87 ml/min/1.73 m² ), it improved significantly at week 4 (+3.93 ± 6.18 ml/min/1.73 m² ; P = 0.008) and week 24 (+2.89 ± 4.26 ml/min/1.73 m² ; P = 0.020) after switching from TDF to TAF.

CONCLUSION

Tenofovir disoproxil fumarate and TAF showed adequate antiviral effects as naïve therapies. Furthermore, switching from TDF to TAF therapy contributed to the maintenance of the antiviral effect and recovery of renal dysfunction.

Prediction of Hepatocellular Carcinoma After Sustained Virological Responses Using Magnetic Resonance Elastography

Direct acting antivirals (DAAs) have made it possible for most patients to achieve sustained virologic responses (SVR).¹ However, some patients developed hepatocellular carcinoma (HCC) even after the eradication of hepatitis C virus²; therefore, it is clinically important to identify patients with a high risk of HCC development after SVR.

55Identification of celastramycin as a novel therapeutic agent for pulmonary arterial hypertension - high-throughput screening of 5,562 compounds

Background

Pulmonary arterial hypertension (PAH) is characterized by enhanced proliferation of pulmonary artery smooth muscle cells (PASMCs) accompanying increased production of inflammatory factors and adaptation of mitochondrial metabolism to a hyperproliferative state. However, at present, since all the drugs in clinical use target pulmonary vascular dilatation, they may not be so effective for patients with advanced PAH.

Purposes

We aimed to discover a novel drug for PAH that inhibits PASMC proliferation.

Methods

In the first screening, we examined 5,562 compounds from our original library using high-throughput screening system to discover a compound that inhibits proliferation of PASMCs from PAH patients (PAH-PASMCs). In the second screening, we performed concentration-dependent assays and counter assays with PAH-PASMCs and PASMCs from healthy donors. We also performed apoptosis assays and mechanistic analysis for inflammation, reactive oxygen species (ROS), and mitochondrial function.

Results

We found that celastramycin, a benzoyl pyrrole-type compound originally found in a bacteria extract, inhibited the proliferation of PAH-PASMCs in a dose-dependent manner with minimal effects on PASMCs from healthy donors. Moreover, celastramycin inhibited proliferation with minimal increase in apoptosis and low rate of cell death. Then, we synthesized 25 analogues of celastramycin, and finally selected the lead compound that significantly inhibited proliferation of PAH-PASMCs and reduced cytosolic ROS levels. Mechanistic analysis demonstrated that celastramycin reduced the protein levels of hypoxia-inducible factor-1α, which was abnormally activated in PAH-PASMCs and impaired aerobic metabolism, and nuclear factor-κB, which induces pro-inflammatory signals, in PAH-PASMCs compared with vehicle controls, leading to reduced secretion of inflammatory cytokines. Importantly, celastramycin treatment reduced the ROS levels in PAH-PASMCs with increased protein levels of NF-E2-related factor 2 (Nrf2), a master regulator of cellular response against oxidative stress. Furthermore, celastramycin treatment improved mitochondrial energy metabolism with recovered mitochondrial network formation in PAH-PASMCs. We also discovered that celastramycin-mediated effects on these transcriptional modulators could be regulated by zinc finger C3H1 domain-containing protein, which is a binding partner of celastramycin. Finally, celastramycin treatment ameliorated pulmonary hypertension in three experimental animal models of PH in mice and rats, accompanied by reduced inflammatory changes in the lungs.

Conclusions

These results indicate that celastramycin ameliorates pulmonary hypertension through inhibition of excessive proliferation of PAH-PASMCs, for which its anti-inflammatory and beneficial effects on mitochondrial energy metabolism may be involved. Thus, celastramycin could be a novel drug for PAH as it exerts anti-proliferative effects on PAH-PASMCs.

P4731Procedure-related acute thrombosis after surgical left atrial appendage occlusion for atrial fibrillation

Background/Introduction

Left atrial appendage (LAA) occlusion is an effective strategy for thromboembolism prevention in patients with atrial fibrillation (AF), and the novel methods of occlusion is various. The acute thrombosis after percutaneous LAA occlusion devices has been recently reported, but thrombus formation after surgical LAA occlusion is still unclear.

Purpose

This study aimed to analyse the incidence and prognosis of thrombus formation on closure stump line in patients with AF who underwent surgical LAA occlusion.

Methods

This study retrospectively analised the data from patients treated with two methods of surgical LAA closure, resection or clipping, from January 2014 to November 2018.

Results

A total of 187 consecutive patients with AF underwent surgical LAA closure (31 clipping and 156 stapler resection). 170 patients (91%) underwent cardiac CT for LAA imaging on postoperative day 2. The incidence of acute procedure-related thrombus formation in full cohort was 19% (35 cases). The incidence of acute thrombus in patients with clipping and resection was 19% and 16%, respectively (Fisher's exact test, p=0.8). All of 35 patients who had thrombus on LAA closure stump line underwent cardiac CT again 3 months after the primary CT. In all patients with secondary cardiac CT, thrombus on LAA closure stump line disappeared. No symptomatic thromboembolism occurred during the follow-up from operation to secondary CT scan.

Conclusion(s)

Thrombus formation on stump after surgical LAA closure may often occur on acute phase. The optimal LAA imaging and anti-coagulation therapy after surgical LAA occlusion will prevent patients with acute thrombus from thromboembolism.

Characterization of supported liquid extraction as a sample pretreatment method for eicosanoids and related metabolites in biological fluids

Sample pretreatment is an important process in liquid chromatography-mass spectrometry-based quantitative lipidomics. Reversed-phase solid phase extraction (RP-SPE) has been widely used for analyzing various types of samples, including aqueous samples such as cell culture media, plasma, serum, urine, and other biological fluids. Because lipid mediators are often protein-bound, prior deproteinization is necessary for their effective recovery. Deproteinization is typically performed by the addition of organic solvents, which requires time-consuming evaporation-reconstitution, or dilution with aqueous solvents before RP-SPE; however, both of these approaches compromise the analytical performance. As a potential alternative, we attempted to utilize supported liquid extraction (SLE), an automation-compatible variant of liquid-liquid extraction, for the determination of eicosanoids and related metabolites in aqueous samples. We screened 81 different sample diluent-eluent conditions and found that the use of 0.1% formic acid-water as the diluent and 0.1% formic acid-methyl acetate as the eluent enabled the optimum recovery of a variety of eicosanoids, except for peptide leukotrienes. The optimized SLE method efficiently removed protein from human plasma, while phospholipids and neutral lipids were modestly recovered. Moreover, the proposed method exhibited a quantitative performance comparable to that of typical ordinary RP-SPE method in the analysis of human platelets stimulated with thrombin receptor-activating peptide 6. Thus, we propose SLE as an attractive option for rapid lipid mediator extraction from aqueous samples.

Polyunsaturated fatty acids promote Plasmodium falciparum gametocytogenesis

The molecular triggers of sexual differentiation into gametocytes by blood stage Plasmodium falciparum, the most malignant human malaria parasites, are subject of much investigation for potential transmission-blocking strategies. The parasites are readily grown in vitro with culture media supplemented by the addition of human serum (10%) or by a commercially available substitute (0.5% AlbuMAX). We found better gametocytemia with serum than AlbuMAX, suggesting suboptimal concentrations of some components in the commercial product; consistent with this hypothesis, substantial concentration differences of multiple fatty acids were detected between serum- and AlbuMAX-supplemented media. Mass spectroscopy analysis distinguished the lipid profiles of gametocyte- and asexual stage-parasite membranes. Delivery of various combinations of unsaturated fatty-acid-containing phospholipids to AlbuMAX-supported gametocyte cultures improved gametocyte production to the levels achieved with human-serum-supplemented media. Maturing gametocytes readily incorporated externally supplied d5-labeled glycerol with fatty acids into unsaturated phospholipids. Phospholipids identified in this work thus may be taken up from extracellular sources or generated internally for important steps of gametocyte development. Further study of polyunsaturated fatty-acid metabolism and phospholipid profiles will improve understanding of gametocyte development and malaria parasite transmission.

Wisteria floribunda agglutinin-positive mac-2 binding protein as an age-independent fibrosis marker in nonalcoholic fatty liver disease

The assessment of liver fibrosis is essential because it correlates with mortality risk in nonalcoholic fatty liver disease (NAFLD). This study aims to examine whether serum fibrosis markers could identify candidate patients likely to have advanced fibrosis. We enrolled 352 patients with NAFLD and performed liver biopsies in 97 patients. The area under the receiver operating characteristic curve (AUROC) of liver stiffness by magnetic resonance elastography for histological advanced fibrosis was 0.910, and the optimal cutoff value was 4.07 kPa. To predict severe liver stiffness (≥4.07 kPa), the AUROC for Wisteria floribunda agglutinin-positive mac-2 binding protein (WFA+-M2BP) and FIB-4 were 0.897 (cutoff value, 1.08) and 0.880 (cutoff value, 2.53), respectively. After stratification of patients into four age groups as quartile, the optimal cutoff values of WFA+-M2BP for predicting severe liver stiffness were similar in each group (1.09, 1.08, 1.10, and 1.12). On the other hand, those of FIB-4 increased in parallel with age (1.47, 2.19, 2.99, and 3.88). In conclusion, WFA+-M2BP was precise for estimating severe liver stiffness in NAFLD with single cutoff value independent of age. Hence, identifying high-risk cases using WFA+-M2BP from a large number of NAFLD patients is clinically significant.

Risk assessment of hepatocellular carcinoma development by magnetic resonance elastography in chronic hepatitis C patients who achieved sustained virological responses by direct-acting antivirals

Prediction of hepatocellular carcinoma (HCC) development after sustained virological response (SVR) is clinically important, and the usefulness of noninvasive markers for prediction HCC have been reported. The aim of this study was to compare the prediction accuracy for HCC development by noninvasive markers. A total of 346 patients with chronic hepatitis C without history of HCC who achieved SVR through direct-acting antivirals were included. Magnetic resonance elastography (MRE) and serum fibrosis markers were measured 12 weeks after the end of treatment, and the subsequent HCC development was examined. The mean observation period was 26.4 ± 7.9 months, and 24 patients developed HCC. Area under the receiver operating characteristic curve of liver stiffness by MRE, Wisteria floribunda agglutinin-positive mac-2 binding protein and FIB-4 for predicting HCC within 3 years was 0.743, 0.697 and 0.647, respectively. The 1/2/3-year rates of HCC development in patients with liver stiffness ≥3.75 KPa were 6.6%, 11.9% and 14.5%, whereas they were 1.4%, 2.5% and 2.5% in patients with liver stiffness <3.75 KPa (P < 0.001). Multivariate analysis revealed that liver stiffness ≥3.75 was an independent predictive factor for HCC development (hazard ratio, 3.51; 95% confidence interval, 1.24-9.99). In subgroup analysis, there were 132 patients who were <73 years old and had liver stiffness <3.75 KPa, and no HCC development was observed in these patients. Diagnostic accuracy for predicting HCC development was higher in MRE than serum fibrosis markers and measurement of liver stiffness by MRE could identify patients with high and low risk of HCC development after SVR.

Myopenia as a significant prognostic factor in BCLC-B intermediate-stage hepatocellular carcinoma treated with sorafenib

e15639

Background: Tyrosine kinase inhibitors (TKI) are important treatment options for unresectable hepatocellular carcinoma (HCC). The survival benefit of sorafernib was demonstrated not only in advanced stage but also for BCLC-B intermediate stage who are refractory to transcatheter arterial chemoembolization by OPTIMIS study. Skeletal muscle mass depletion (Myopenia) is a poor prognostic factor in HCC treated by resection or loco-reginal ablation, but its effect on survival in TKI treated patients, especially in those within BCLC-B stage remains unclear. The aim of the present study is to elucidate the impact of myopenia on survival among HCC treated with sorafenib, especially in BCLC-B stage. Methods: In 213 patients who started treatment with sorafenib between 2009 and 2016, myopenia at baseline was determined by using skeletal muscle index calculated from CT images of the third lumber vertebra level. The impact of myopenia on survival was analyzed in whole patients, after stratification by BCLC stage, and after matching for backgrounds within BCLC-B patients. Results: The median survival in whole, BCLC-C, and –B was 13.7, 8.7 and 15.2 months, respectively. Myopenia was not a significant prognostic factor in whole patients and in BCLC-C stage. However, among BCLC-B patients (n = 104), survival was significantly better in patients with no myopenia (p = 0.05). Among them, 85 patients who continued sorafenib for more than 8 weeks were extracted and those with or without myopenia were matched for backgrounds by propensity score. Backgrounds including etiology, Child-Pugh score, BMI, AFP and PIVKA-Ⅱwas not different between myopenia (n = 30) and no myopenia group (n = 30) after matching. The overall survival at 6-, 12-, and 24-months was 96%, 74%, and 62% in no myopenia group which was significantly better compared to 89%, 64%, and 28% in myopenia group (p = 0.019). The hazard ratio was 2.12 (95% CI 1.11-4.03). Conclusions: Absence of myopenia predicts favorable outcome in sorafenib treated HCC patients within BCLC-B intermediate stage.

Novel roles of lipid mediators in psoriatic skin inflammation

Psoriasis is a common chronic inflammatory cutaneous disease thought to arise as a result of infiltration of inflammatory cells and activation of keratinocytes. Psoriasis has been considered as a classical Th1 disease; however, Th17 cells are attracting much interest. Previous knowledge on the pathology of psoriasis has been obtained mostly through the study of human data and samples. In addition, recently developed animal models for psoriatic skin inflammation recapitulates the hallmarks of human psoriasis and provide us new insights on psoriasis. Lipid mediators and their receptors regulate a variety of physiological processes and involved in multiple pathologies including immune-related diseases. Here, we explored novel lipid mediators involved in psoriatic skin inflammation using clinical samples and imiquimod-induced psoriasis model. In particular, mass spectrometry analysis for multiplex quantitation of eicosanoids using imiquimod-treated murine skin samples revealed unique kinetics of various lipid mediators in the time-series from early induction phase to chronic resolution phase. These data motivated us to focus on some lipid mediators such as leukotriene B4 (LTB4) and prostaglandin E2 (PGE2). As an example, BLT1 (known as LTB4 receptor) and CXCR2 have been revealed to coordinately promote neutrophil infiltration into the skin during the early phase of imiquimod-induced inflammation. Further analysis on PGE2 is in progress and some data indicates the novel functions of PGE2 and mPGES-1, an upstream enzyme for PGE2 production, in the pathogenesis in psoriasis. These insights may aid in the rational design of novel treatments for broad spectrum of inflammatory and immune disorders beyond psoriasis.

Absorbable barbed suture device for laparoscopic peritoneal closure after hernia repair via the transabdominal preperitoneal approach: A single-center experience with 257 cases

INTRODUCTION

The laparoscopic transabdominal preperitoneal approach requires peritoneal closure and technically skilled knotting. We have started to use a barbed running suturing device (V-Loc 180) without knotting for transabdominal preperitoneal repair of hernias. This study aimed to determine whether using V-Loc 180 was safe and shortened the time for laparoscopic peritoneal closure.

METHODS

Between December 2010 and February 2017, 3-0 V-Loc 180 and a multifilament absorbable running suture (3-0 Vicryl) were used for three-port transabdominal preperitoneal repair of inguinal hernia in 363 cases. Data including peritoneal closure time and the complications were retrospectively recorded.

RESULTS

Factors identified as significantly prolonging the peritoneal closure time were the hernia side (P = 0.0269), the type of hernia (P = 0.001), the suture device used (P < 0.0001), and the surgeon's experience (P < 0.0001). Use of the barbed suture was associated with a significantly shorter peritoneal closure time than the multifilament suture (mean closure time: 10.2 and 12.7 min, respectively). While there were no postoperative complications in the barbed suture group, there were two cases (1.9%) of postoperative complications in the multifilament suture group (P = 0.0272).

CONCLUSION

We demonstrated that the use of the barbed suturing device for laparoscopic peritoneal closure was safe and feasible.

An accurate and versatile method for determining the acyl group-introducing position of lysophospholipid acyltransferases

Lysophospholipid acyltransferases (LPLATs) incorporate a fatty acid into the hydroxyl group of lysophospholipids (LPLs) and are critical for determining the fatty acid composition of phospholipids. Previous studies have focused mainly on their molecular identification and their substrate specificity regarding the polar head groups and acyl-CoAs. However, little is known about the positional specificity of the hydroxyl group of the glycerol backbone (sn-2 or sn-1) at which LPLATs introduce a fatty acid. This is mainly due to the instability of LPLs used as an acceptor, especially for LPLs with a fatty acid at the sn-2 position of the glycerol backbone (sn-2-LPLs), which are essential for the enzymatic assay to determine the positional specificity. In this study, we established a method to determine the positional specificity of LPLAT by preparing stable sn-2-LPLs in combination with PLA₂ digestion, and applied the method for determining the positional specificity of several LPLATs including LPCAT1, LYCAT and LPCAT3. We found that LPCAT1 introduced palmitic acid both at the sn-1 and sn-2 positions of palmitoyl-LPC, while LYCAT and LPCAT3 specifically introduced stearic acid at the sn-1 position of LPG and arachidonic acid at the sn-2 position of LPC, respectively. The present method for evaluating the positional specificity could also be used for biochemical characterization of other LPLATs.

Real-life experience of lusutrombopag for cirrhotic patients with low platelet counts being prepared for invasive procedures

BACKGROUND AND AIMS

The present study aimed to report our real-life experience of the TPO receptor agonist lusutrombopag for cirrhotic patients with low platelet counts.

METHODS

We studied platelet counts in 1,760 cirrhotic patients undergoing invasive procedures at our hospital between January 2014 and December 2017. In addition, we studied 25 patients who were administered lusutrombopag before invasive procedures between June 2017 and January 2018. Effectiveness of lusutrombopag to raise platelet counts and to avoid transfusion and treatment-related adverse events were analyzed.

RESULTS

In 1,760 cirrhotic patients without lusutrombopag prior to invasive procedures, proportion of patients whose platelet counts <50,000/μL and needed platelet transfusions were 66% (n = 27/41) for radiofrequency ablation, 43% (n = 21/49) for transarterial chemoembolization, and 55% (n = 21/38) for endoscopic injection sclerotherapy / endoscopic variceal ligation, respectively. In 25 cirrhotic patients treated by lusutrombopag prior to the invasive procedures, platelet counts significantly increased compared with baseline (82,000 ± 26,000 vs. 41,000 ± 11,000/μL) (p < 0.01). Out of 25 patients, only 4 patients (16%) needed platelet transfusion before the invasive procedures. The proportion of patients with low platelet count and who needed platelet transfusions was significantly low in patients treated with lusutrombopag compared to those not treated with lusutrombopag (16% (4/25) vs. 54% (69/128), p = 0.001). Platelet counts after lusutrombopag treatment and prior to invasive procedures were lower in patients with a baseline platelet count ≤30,000/μL (n = 8) compared with those with a baseline platelet count >30,000/μL (n = 17) (50,000 ± 20,000 vs 86,000 ± 26,000/μL, p = 0.002). Patients with a baseline platelet count ≤30,000/μL with spleen index (calculated by multiplying the transverse diameter by the vertical diameter measured by ultrasonography) ≥40 cm2 (n = 3) had a lower response rate to lusutrombopag compared to those with spleen index <40 cm2 (n = 5) (0% vs. 100%, p = 0.02). Hemorrhagic complication was not observed. Recurrence of portal thrombosis was observed and thrombolysis therapy was required in one patient who had prior history of thrombosis.

CONCLUSIONS

Lusutrombopag is an effective and safe drug for thrombocytopenia in cirrhotic patients, and can reduce the frequency of platelet transfusions.

Complete renal response at 12 months after induction therapy is associated with renal relapse-free rate in lupus nephritis: a single-center, retrospective cohort study

Background

Lupus nephritis (LN) is a major risk factor for overall morbidity and mortality in systemic lupus erythematosus (SLE).

Methods

We retrospectively analyzed cases of proliferative and membranous LN patients who underwent a renal biopsy at our hospital in 1993–2016. We analyzed the association between complete renal response (CR) rates at 12 months after induction therapy and predictive factors for CR and their association with renal flares.

Results

Of the 95 cases analyzed, we were able to track the therapeutic responses of 81 patients at 12 months after their induction therapy. The median follow-up duration after renal biopsy was 51 months (interquartile range: 16.5–154.5 months). The Cox proportional hazards model showed that, compared to not attaining CR at 12 months, the attainment of CR at 12 months was correlated with being free from renal flares. The multivariate logistic analysis revealed that the predictive factors for CR at 12 months were the anti-La/SSB antibodies (U/ml) (odds ratio (OR) 1.22, 95% confidence interval (CI) 1.01–1.63, p = 0.0220), blood urea nitrogen (BUN) (OR 0.68, 95% CI 0.44–0.90, p = 0.00048) and serum β2 microglobulin (MG) (OR 0.26, 95% CI 0.06–0.74, p = 0.00098) levels.

Conclusions

Among LN patients, being free from renal flares was associated with attaining CR at 12 months after induction therapy. Anti-La/SSB antibodies were a positive predictive factor, and BUN and serum β2MG levels were negative predictive factors of CR at 12 months.