Relativistic magnetic reconnection in laser laboratory for testing an emission mechanism of hard-state black hole system

Magnetic reconnection in a relativistic electron magnetization regime was observed in a laboratory plasma produced by a high-intensity, large energy, picoseconds laser pulse. Magnetic reconnection conditions realized with a laser-driven several kilotesla magnetic field is comparable to that in the accretion disk corona of black hole systems, i.e., Cygnus X-1. We observed particle energy distributions of reconnection outflow jets, which possess a power-law component in a high-energy range. The hardness of the observed spectra could explain the hard-state x-ray emission from accreting black hole systems.

SAT0458 THE POLYMORPHISM ON FAT MASS AND OBESITY ASSOCIATED GENE (FTO) WAS ASSOCIATED WITH LOW BONE MASS IN JAPANESE COMMUNITY DWELLING POPULATION

Background:

A polymorphism onFTO(OMIM 610966) was reported as a causal variant for obesity, plays a critical rule not only in amount of adipose tissue but also in function of mitochondrial thermogenesis1.

Objectives:

To examine the association of the genotype on a single nucleotide polymorphism onFTOwith bone health.

Methods:

FTO rs1421085 polymorphism was genotyped in 1,601 community-dwelling Japanese participants. This cross-sectional study was nested in Nagasaki Islands Study, which is a prospective cohort in Goto City, in islands of Japan. Participants were recruited at medical check-ups for community dwelling population.

Bone mass of the calcaneus was evaluated with stiffness index calculated using a quantitative ultrasound measurement. Low bone mass was defined as a stiffness index less than 80 % of the young adult mean.

Sera and peripheral blood mononuclear cells were obtained. The SNP of rs1421085 was genotyped using hydrolysis probe. The chi-squared test was used to determine whether the variants were in equilibrium in that population. Trend for the median of BMI among genotypes was assessed using the Jonckheere-Terpstra test. Potential associations between FTO polymorphism and overweight and between the polymorphism and low bone mass were evaluated using logistic regression. All analyses were carried out using SPSS 23.

Results:

Genotype and allele frequencies for the polymorphism were in Hardy-Weinberg equilibrium (minor allele frequency 0.16, p = 0.40) in 1,601 community-dwelling persons (mean age was 68.5 years in men and 68.1 years in women).

There were significant associations between the minor allele and higher median of BMI on dose dependent manner in men (p = 0.04 for trend in men and p = 0.10 for trend in women, respectively), and between the minor allele and overweight (>25 in BMI, OR 1.52, 95%CI 1.07 2.14, p=0.02 in men, OR 1.48, 95%CI 1.16 1.95, p=0.01 in women).

Logistic regression analysis showed a significant protective association in men with carriers of minor allele against low bone mass after an adjustment for age and BMI (OR 0.63, 95%CI 0.44 0.90, p=0.01 in men, not significant in women).

Conclusion:

Our study indicated significant associations of the polymorphism onFTOwith BMI and bone mass among community dwelling men. The polymorphism may play a rule in a part of bone health with higher BMI and other beneficial functions.

References:

[1]N Engl J Med. 2015; 373: 895-907

Disclosure of Interests:

None declared

THU0337 THE EFFECTIVENESS OF PLASMA EXCHANGE THERAPY FOR ANTI-MDA5 ANTIBODY-POSITIVE REFRACTORY INTERSTITIAL LUNG DISEASE

Background:

This is an extended report of our study [1]. Anti-melanoma differentiation-associated gene 5 (MDA5) antibodies, which are closely related to interstitial lung disease (ILD) with or without rapid progression, are a type of myositis-specific autoantibody. Since rapid progressive-ILD (RP-ILD) with anti-MDA5 antibodies is refractory and fatal, intensive immunosuppressive therapy with combination calcineurin inhibitor, and intravenous pulse cyclophosphamide was developed, and was shown to improve patient survival and prognosis [2]. However, 20–30% of cases were still fatal, and several additional therapies have been reported e.g. tofacitinib [3] and plasma exchange therapy (PE) [1, 4, 5].

Objectives:

We evaluated the effect of plasma exchange (PE) on survival in patients with refractory RP-ILD who were positive for anti-MDA5 antibodies.

Methods:

Among 167 patients newly diagnosed with PM/DM, clinically amyopathic DM, or cancer associated myositis from 2008 to 2019 at our hospital, 12 were diagnosed with refractory RP-ILD and were positive for anti-MDA5 antibodies. PE was used as an adjunct to standard therapy and consisted of fresh frozen plasma as replacement solution. The primary outcome was non-disease-specific mortality. anti-MDA5 antibody titres were measured by ELISA using the MESACUP anti-MDA5 test in 155 patients whose serum was frozen and stored at the time of diagnosis.

Results:

Anti-MDA5 antibodies were detected in 35 patients, of whom 26 were diagnosed with RP-ILD and 11 were refractory to intensive immunosuppressive therapy. Seven patients received PE (PE group) and four did not (non-PE group). The 1-year survival rate of the PE group was higher than that of the non-PE group (100% and 25%, respectively, P = 0.011). Regarding adverse events associated with PE, two patients had anaphylactic shock, one had high fever due to fresh frozen plasma allergy and one had a catheter infection. All adverse events resolved with appropriate treatment.

Conclusion:

We evaluated the association between 1-year survival rate and PE for refractory RP-ILD in patients positive for anti-MDA5 antibodies. Intensive immunosuppressive therapy improved the survival rate in RP-ILD patients with anti-MDA5 antibodies, but 20-30% of cases were still fatal. PE could be administered to patients with active infectious disease who were immunocompromised by intensive immunosuppressive therapy. PE may be considered in refractory RP-ILD patients positive for anti-MDA5 antibodies.

References:

[1]Nakashima R, Hosono Y, Mimori T. Clinical significance and new detection system of autoantibodies in myositis with interstitial lung disease. Lupus. 2016;25:925-33.

[2]Kurasawa K, Arai S, Namiki Y et al. Tofacitinib for refractory interstitial lung diseases in anti-melanoma differentiation-associated 5 gene antibody-positive dermatomyositis. Rheumatology. 2018;57:2114-9.

[3]Silveira MG, Selva-O’Callaghan A, Ramos-Terrades N et al. Anti-MDA5 dermatomyositis and progressive interstitial pneumonia. QJM. 2016;109:49-50.

[4]Endo Y, Koga T, Suzuki T et al. Successful treatment of plasma exchange for rapidly progressive interstitial lung disease with anti-MDA5 antibody-positive dermatomyositis: A case report. Medicine (Baltimore). 2018;97:e0436.

[5]Abe Y, Kusaoi M, Tada K et al. Successful treatment of anti-MDA5 antibody-positive refractory interstitial lung disease with plasma exchange therapy. Rheumatology. 2019.

Acknowledgments:

Funding: This work was supported by Japan Society for the Promotion of Science KAKENHI Grant Number JP18K15433.

Disclosure of Interests:

None declared

FRI0179 A STUDY ON THE ACHIEVEMENT OF LUPUS LOW DISEASE ACTIVITY STATE AND QUALITY OF LIFE IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS: FROM THE JUNTENDO UNIVERSITY SLE PROSPECTIVE REGISTRY STUDY

Background:

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease of unknown etiology that affects mostly young women. Multiorgan complications and prolonged treatment significantly cause physical and mental stress in patients. Improving patients’ quality of life (QOL) in SLE treatment is essential. We examined the treatment effects on disease activity and QOL of SLE patients.

Objectives:

In recent years, lupus low disease activity state (LLDAS) has been proposed as a treatment target for SLE. Patients who achieve LLDAS have a low recurrence rate for lupus and a low risk of serious complications (1). The aim of this study is to investigate whether achieving LLDAS reduces not only recurrence rate and complications of SLE but also improves patients’ QOL.

Methods:

A total of 104 SLE patients were enrolled in our prospective SLE registry study (Juntendo, Multi-center, Prospective cohort for investigation of clinical course and outcome in SLE: JUMP) conducted at our institution. SLE was diagnosed using the American College of Rheumatology (ACR) 1982 criteria (revised in 1997). QOL was evaluated using the standard version of the 36-item short form health survey version 2 (SF36v2). Participants were divided into the LLDAS achievement and non-achievement groups, and the characteristics of each group including results of SF36v2 were examined.

Results:

This study included 104 SLE patients, 94 female and 10 male, and the average age and disease duration were 46.4±13.8 and 14.5±11.3 years, respectively. The average corticosteroid dose was 8.0±17.4 mg/day in terms of prednisolone, and anti-dsDNA antibody titer was 16.8±38.5 IU/ml. Of the 104 patients, 57 achieved LLDAS. The subscale’s standard scoring using SF36v2 for role physical (RP) was 78.9±24.0 and 64.6±27.6 (P<0.01), general health (GH) was 50.0±17.0 and 42.0±19.3 (P<0.05), vitality (VT) was 55.8±15.8 and 38.0±24.1 (P<0.01), social functioning (SF) was 82.0±20.7 and 66.5±26.3 (P<0.01), role emotional (RE) was 89.0±16.1 and 73.4±28.1 (P<0.01), and mental health (MH) was 72.4±15.9 and 58.3±21.8 (P<0.01) in the LLDAS achievement and non-achievement groups, respectively. Furthermore, scoring based on the national standard value in the LLDAS achievement group showed that two categories were >50. However, in the LLDAS non-achievement group, all categories were <50. In particular, RP, GH, VT, SF, RE, and MH of the LLDAS achievement group had significantly higher scores than the LLDAS non-achievement group (RP and GH: p<0.05 and VT, SF, RE and MH: p<0.01).

Conclusion:

Results of examining the association between LLDAS and QOL using SF36v2 in SLE patients showed that patients who achieved LLDAS had significantly better standard statistical scores in many subscale categories. Thus, LLDAS achievement as a treatment target for SLE patients greatly contributes to improving patients’ QOL.

References:

[1]Franklyn K, et al. Definition and initial validation of a Lupus Low Disease Activity State (LLDAS).Ann Rheum Dis. 2016 Sep;75(9):1615-21.

Disclosure of Interests:

None declared

1044 Simple echocardiographic scoring in screening for aortic stenosis by emergency physicians in the emergency department

Background; Aortic stenosis (AS) is one of the important critical diseases and may influence hemodynamics in cardiovascular or non-cardiovascular emergency, however, there is no established methodology to diagnose AS in a focused cardiac ultrasound (FOCUS). We have previously reported that our developed visual AS score was a simple index for AS screening using rapid echocardiography and it could successfully diagnose clinically significant AS. The purpose of the present study was to evaluate the diagnostic accuracy of visual AS score assessed by emergency physicians in the emergency department. Methods; Visual AS score was calculated as the sum of the scores of each three aortic cusp’s opening in a short-axis view scored as follows: 0 = not restricted, 1 = restricted, or 2 = severely restricted; and classified in 0 – 6 as we previously reported. Emergency physicians who did not specialize in cardiology or ultrasonography underwent basic 30 minutes training to visualize aortic valve in a short-axis view and to assess visual AS score beforehand. They performed echocardiography and evaluated visual AS score in emergency outpatients with suspected cardiovascular diseases such as chest symptom, consciousness disorder, abnormal vital signs, heart murmur or abnormal electrocardiogram in the emergency department. Then, another assessment of visual AS score and complete echocardiography including quantitative assessment of AS was performed by expert sonographers. Aortic valve area index (AVAI) was calculated using continuity equation and body surface area, and an AVAI &gt; 0.85 cm/m2, 0.6 - 0.85 cm/m2, and &lt; 0.6 cm/m2 were defined as none or mild, moderate and severe AS, respectively. Results: Sixty patients underwent evaluations of visual AS score by emergency physicians. Visual AS score could not be assessed in 5 patients and continuity equation could not be evaluated in 2 patients, both due to poor echocardiographic imaging quality. Visual AS scores assessed by emergency physicians and expert sonographers showed strong positive correlation (R = 0.94, P &lt; 0.0001). Fourteen patients (26 %) including 6 with shock or hypotension, 3 with congestive heart failure, 2 with syncope, 1 with acute myocardial infarction, 1 with suspected cardiac tamponade and 1 with abnormal electrocardiogram had moderate or more degree of AS in complete echocardiography performed by expert sonographers. Visual AS score 3 or more assessed by emergency physicians had 86 %, 100 %, 100 % and 95 % of a diagnostic sensitivity, specificity, positive predictive value and negative predictive value, respectively. Conclusion: Visual AS score in FOCUS is useful to screen for AS for emergency physicians who do not specialize in cardiology.

Bifunctional carbon Ni/NiO nanofiber catalyst based on 5-sulfosalicylic acid for conversion of C5/C6 carbohydrates into ethyl levulinate

A method was developed for preparing bifunctional carbon Ni/NiO nanofiber catalysts that promote efficient one-pot conversion of C5/C6 carbohydrates into levulinate esters in alcohol solvents.

CAPABILITIES OF THE ARADOS-WG03 REGIONAL NETWORK FOR LARGE-SCALE RADIOLOGICAL AND NUCLEAR EMERGENCY SITUATIONS IN ASIA

In 2015, the Asian Radiation Dosimetry Group established a regional network of biological dosimetry laboratories known as the ARADOS-WG03 (Working Group 03; Biological Dosimetry). A survey was conducted in 2017 to evaluate the capabilities and capacities of the participating laboratories for emergency preparedness and responses in large-scale nuclear and/or radiological incidents. The results of this survey were identified and assessed. The data provide important information on the current state of emergency cytogenetic biological dosimetry capabilities in the Asian region.

P924Prognostic significance of moderate primary mitral regurgitation and atrial fibrillation

Background

Severe primary mitral regurgitation [degenerativeMR (DMR)] is associated with poor outcome, including cardiac death and admission due to worsening heart failure. Whereas little information is available regarding the characteristics of moderate DMR and their impact on prognostic outcome.

The aim of the present study was to investigate the prognosis and its determinant in patients with moderate DMR.

Methods

From 13,700 consecutive patients who underwent transthoracic echocardiography. We selected moderate DMR but without other underlying cardiac diseases. Characteristics and event free rate as compared with age- and gender-matched patients with none to mild MR.

Results

Of a total of our cohort, 185 (1%) patients had moderate DMR, and we compared with 185 age- and gender-matched patients with none to mild MR. During the follow-up period of 1372±655 days, 30 patients (8%) met the composite endpoint defined as cardiac death and admission due to worsening heart failure. Kaplan-Meier analysis showed patients with moderate DMR was significantly associated with a poor outcome compared to patients with none to mild MR (log-ranktest P<0.0001). Cox proportional hazard ratio revealed thatmoderate MR and atrial fibrillation (AF) were the independent predictors of the composite endpoint.

Prgnostic outcome: AF and moderate DMR

Conclusions

Patients withmoderate DMR and concomitant AF had a significant poor outcome. An activesurveillance and some intervention for AF and moderate MR may be required.

Agreement of intracranial vessel diameters measured on 2D and 3D digital subtraction angiography using an automatic windowing algorithm

BACKGROUND AND PURPOSE

Precise vessel measurement plays a major role in size selection of stents used for the treatment of intracranial aneurysms and became even more critical after the introduction of flow diverter stents. We assessed agreement between intracranial vessel diameters of aneurysm patients measured on 2D digital subtraction (2D DSA) and 3D volume rendering digital subtraction angiography (3D DSA) images using an automatic windowing algorithm.

MATERIALS AND METHODS

Ten patients with intracranial aneurysms were enrolled and 120 measurement points were selected on both 2D and 3D DSA images acquired by a biplane angiographic system. Automatic windowing was applied to the 3D DSA images. Inter-method agreement of vessel measurements on 2D and 3D DSA images was assessed by Bland Altman plots and intraclass correlation coefficients (ICC). Inter- and intra-rater agreement of measurements on 3D DSA images were assessed by ICCs.

RESULTS

The mean differences between measurements on 2D and 3D DSA images were 0.14mm for the ICA, and 0.18mm for the ACA and MCA, which is about the size of one 3D DSA image voxel. For ICA measurements, inter-method, inter-rater and intra-rater agreements were good or excellent (consistency and absolute ICC≥0.95). For ACA and MCA measurements, the inter-method, inter-rater and intra-rater agreements were also good or excellent (consistency ICC=0.94, 0.89 and 0.93, absolute ICC=0.83, 0.84 and 0.85 respectively).

CONCLUSIONS

Vessel diameters may be measured on 3D DSA images with sufficient reliability for clinical use when applying an automatic windowing algorithm.

Enhancing laser beam performance by interfering intense laser beamlets

Increasing the laser energy absorption into energetic particle beams represents a longstanding quest in intense laser-plasma physics. During the interaction with matter, part of the laser energy is converted into relativistic electron beams, which are the origin of secondary sources of energetic ions, γ-rays and neutrons. Here we experimentally demonstrate that using multiple coherent laser beamlets spatially and temporally overlapped, thus producing an interference pattern in the laser focus, significantly improves the laser energy conversion efficiency into hot electrons, compared to one beam with the same energy and nominal intensity as the four beamlets combined. Two-dimensional particle-in-cell simulations support the experimental results, suggesting that beamlet interference pattern induces a periodical shaping of the critical density, ultimately playing a key-role in enhancing the laser-to-electron energy conversion efficiency. This method is rather insensitive to laser pulse contrast and duration, making this approach robust and suitable to many existing facilities.

Enhanced coupling of laser energy to the target particles is a fundamental issue in laser-plasma interactions. Here the authors demonstrate increased photon absorption leading into higher laser to electron and proton energy transfer through the interference of multiple coherent beamlets.

A multichannel gated neutron detector with reduced afterpulse for low-yield neutron measurements in intense hard X-ray backgrounds

A design of multichannel gated photomultiplier tube (PMT) is presented for the 960-channel neutron time-of-flight detector at the Institute of Laser Engineering of Osaka University. This is important for the fusion science and the nuclear photonics where intense hard X-rays are generated from the interaction of ultra-short laser pulse of petawatt power density with matter. The hard X-rays often overload PMTs and cause signal-induced background noises called afterpulses, making the detection of subsequent neutrons impossible. For this reason, the PMTs are coupled with an electrical time-gating (ETG) system to avoid overloading. The ETG system disables the PMT by modulating the dynode potential during the primary X-ray flash. An after-pulsing suppression technique is demonstrated by applying a reverse bias voltage between the photocathode and the first dynode. The presented multichannel scheme provides a gate response time of 80 ns, a signal cutoff ratio of 2.5 × 10², and requires reasonably low power consumption.

A large-aperture high-sensitivity avalanche image intensifier panel

A large-aperture high-sensitivity image intensifier panel that consists of an avalanche photodiode array and a light-emitting diode array is presented. The device has 40% quantum efficiency, over 10⁴ optical gain, and 80-ns time resolution. The aperture size of the device is 20 cm, and with the current manufacturing process, it can be scaled to arbitrarily larger sizes. The device can intensify the light from a single particle scintillation emission to an eye-visible bright flash. The image resolution of the device is currently limited by the size of the avalanche photodiode that is 2 mm, although it can be scaled to smaller sizes in the near future. The image intensifier is operated at a small voltage, typically +57 V. The device can be applied to various applications, such as scintillation imaging, night vision cameras, and an image converter from non-visible light (such as infrared or ultraviolet) to visible light.

Strange Hemodynamic Attractor Parameter with 1/R Total Artificial Heart Automatic Control Algorithm

To evaluate the automatic control algorithm of the total artificial heart (TAH) as an entity, and not just as parts, a non-linear mathematical analyzing technique including chaos theory was utilized. Chronic experiments on the biventricular bypass type artificial heart implantation were performed in healthy adult goats after the natural ventricles were removed. Hemodynamic time series data were recorded under the awake standing condition with TAH 1/R and fixed driving. Time series data were recorded on a magnetic tape and analyzed on a personal computer system with an A-D converter. Using the nonlinear mathematical technique, the time series data were embedded into the phase space and the Lyapunov numerical method was carried out for the quantitative evaluation of the sensitive dependence on the initial condition of the reconstructed attractor. Calculation of the largest Lyapunov exponents suggested that the reconstructed attractor of the left pump output during TAH 1/R control was a larger dimensional strange attractor, a characteristic pattern of deterministic chaos. A total system indicating chaotic dynamics was thought to be a flexible and intelligent control system. Thus, our results suggest that 1/R TAH control may be suitable for the biventricular assist type total artificial heart.

Right Heart Function during Left Ventricular Assistance in an Open-Chest Porcine Model of Acute Right Heart Failure

Changes in the right ventricular function measured with a thermodilution ejection fraction catheter have been recorded in open-chest normal pigs and pigs with acute right heart failure (RVF) undergoing left ventricular assistance with a pneumatic-sactype device (LVAD). To produce acute right heart failure, 5 pigs underwent ligation of the right ventricular free wall coronary arteries. Compared with normal pigs, cardiac output in ligated pigs fell by 21% (7.5 ± 0.5 vs 9.5 ± 1.2 L/min; p < 0.05) and the right ventricular end diastolic pressure rose (11.4 ± 2.6 vs 5.7 ± 3.6 vs mmHg: p <0.05). With the left ventricular assist device connected, the right atrial pressure was increased to 3, 5, 7, 10 and 12 mmHg by volume loading while maintaining the haematocrit at 35 ± 6%. The right ventricular stroke work index (RVSWI) increased with volume loading in normal pigs. In RVF pigs, RVSWI increased significantly with the LVAD (59.2 ± 5.8 vs 23.5 ± 7.8 mmHg ml/min/kg, p<0.01), approaching that of normal pigs (62.3 ± 4.8 mmHg ml/min/kg). Similar changes were observed in the cardiac output and right ventricular stroke volume. These results show that, in this model of open-chest, mild, acute right heart failure, left ventricular assistance allows right ventricular function to return to normal, despite volume overloading, by decreasing right ventricular after load and increasing right ventricular compliance