Search for Gamma-Ray Spectral Lines from Dark Matter Annihilation up to 100 TeV toward the Galactic Center with MAGIC

Linelike features in TeV γ rays constitute a "smoking gun" for TeV-scale particle dark matter and new physics. Probing the Galactic Center region with ground-based Cherenkov telescopes enables the search for TeV spectral features in immediate association with a dense dark matter reservoir at a sensitivity out of reach for satellite γ-ray detectors, and direct detection and collider experiments. We report on 223 hours of observations of the Galactic Center region with the MAGIC stereoscopic telescope system reaching γ-ray energies up to 100 TeV. We improved the sensitivity to spectral lines at high energies using large-zenith-angle observations and a novel background modeling method within a maximum-likelihood analysis in the energy domain. No linelike spectral feature is found in our analysis. Therefore, we constrain the cross section for dark matter annihilation into two photons to ⟨σv⟩≲5×10^{-28}  cm^{3} s^{-1} at 1 TeV and ⟨σv⟩≲1×10^{-25}  cm^{3} s^{-1} at 100 TeV, achieving the best limits to date for a dark matter mass above 20 TeV and a cuspy dark matter profile at the Galactic Center. Finally, we use the derived limits for both cuspy and cored dark matter profiles to constrain supersymmetric wino models.

Bounds on Lorentz Invariance Violation from MAGIC Observation of GRB 190114C

On January 14, 2019, the Major Atmospheric Gamma Imaging Cherenkov telescopes detected GRB 190114C above 0.2 TeV, recording the most energetic photons ever observed from a gamma-ray burst. We use this unique observation to probe an energy dependence of the speed of light in vacuo for photons as predicted by several quantum gravity models. Based on a set of assumptions on the possible intrinsic spectral and temporal evolution, we obtain competitive lower limits on the quadratic leading order of speed of light modification.

SAT0235 THE EFFECT OF ANTIPHOSPHOLIPID ANTIBODIES ON APTT WAVEFORM PATTERNS

Background:

Patients with antiphospholipid antibody (aPL) are said to be at increased risk for thrombosis, however it is difficult to predict whether they will develop thrombosis. In recent years, it has been revealed that the characteristics of the second derivative curve of APTT waveform with aPL positive patient is biphasic changes1,2. As first step in predicting the risk of thrombosis, we sought to understand the effect of aPL on APTT waveform patterns.

Objectives:

To analyze the characteristics of APTT waveforms according to the background diseases and the presence of aPL

Methods:

Patients who underwent coagulation function tests from 2017 to 2019 were analyzed. A coagulation waveform (Clot waveform: CW) was drawn using a fully automatic coagulation time measuring device manufactured by Instrumentation Laboratory From the APTT waveform, the 1st derivative curve (DC) indicating the coagulation speed and the 2nd DC indicating the coagulation acceleration were depicted to measure the 1st DC height, 2nd DC peak 1 time, and 2nd DC peak 1 height (Figure12). Patients were devided into CTD with aPL-negative patients (group A), aPL-positive patients with no prior thrombosis (group B), and antiphospholipid antibody syndrome (APS) (group C). Patients characteristics and aPL (anti-cardiolipin [CL] antibody IgM, anti-CL antibody IgG, anti-CLβ2GP1 complex antibody, LA-APTT, and LA- DRVVT) status were examind. A further analysis was performed according to the numbers of positive aPL. Comparison between the three groups were made by the one-way ANOVA method, with significant differences set as p-values <0.1. Factors with significant differences were analyzed by Steel-Dwass test. APTT waveforms was analyzed according to the numbers of positive aPL by least squares methods. Furthermore, to determine the cut off value of APTT, 1st DC height, 2nd DC peak 1 time, and 2nd DC peak 1 height for each case with 2 or more positive aPLs and 3 positive aPLs, area under the curve (AUC) of the receiver operating characteristic (ROC) curve, sensitivity and specificity were caliculated.

Figure 1.

Results:

The APTT waveform was analyzed in 61 patients (51 women, 83.6%) with average age of 54.1 ± 17.1 years. Group A was 26 cases, Group B was 18 cases, and Group C was 17 cases. APTT, 2nd DC peak1 time, 2nd DC peak1 height, 1st DC peak time were significantly different among A, B, and C groups (p <0.01). APTT, 1st DC peak height, 2nd DC peak 1 time, and 2nd DC peak 1 height differed among the number of aPL (p < 0.01, respectively). APTT and 2nd DC peak1 time prolonged by 9.43 (seconds) and 16.3 (seconds) respectively according to the number of aPLs increased, and 1st DC peak height (mabs/s) and 2nd DC peak1 height (mabs/s2) decreased by 56.4 (mabs/s) and 223.9 (mabs/s2) respectively according to the number of aPLs decreased (Table 1). APTT> 35.2 (seconds) (sensitivity 80%, specificity 80.4%), 2nd DC peak1 height> 302 (mabs/s2) (sensitivity 80%, specificity 91.3%) were relevant to the presence of two or more aPLs and APTT> 35.2 (seconds) (sensitivity 100%, specificity 80%), 2nd DC peak1 height> 302 (mabs/s2) (sensitivity 100%, specificity 90%) were relevant to the presence of three aPLs.

Table 1.The number of positive aPL0123p valueThe number of cases2719411APTT(seconds)28.9[26.8, 31.4]30.9[29.1, 38.2]31.1[27.3, 54.2]60.7[45.9, 73.7]0.00012nd DC peak time (seconds)29.2[26.8, 30.7]33.7[31, 41.7]36.1[31.5, 99]75.8[50.5, 102.4]0.00012nd DC peak height (mabs/s2)839.9[666.1, 962.2]669.6[346.4, 946]608.4[137.8, 956.7]119.3[30.6, 196]0.00011st DC peak height (mabs/s)309.6[260.6, 355.1]271.5[168, 353]241.8[96.3, 364.0]135.6[76.8, 163]0.0001

Conclusion:

The presence of aPL was more related to the 2nd DC peak1 height of APTT waveform than APTT. A detailed review of the APTT waveform may further predict future thrombosis risk.

References:

[1]Tokunaga N, et al. Blood Coagul Fibrinolysis. 2016;27:474-476.

[2]Matsumoto T, et al. Int J Hematol. 2017;105:174-183.

Disclosure of Interests:

YASUO SUZUKI: None declared, Asako Mitsui: None declared, Yoshiki Yamamoto: None declared, Kentaro Noda: None declared, Ayako Nakajima Grant/research support from: AN has received research grants from Chugai Pharmaceutical Co., Ltd., Mitsubishi Tanabe Pharma Co., Pfizer Japan Inc., Consultant of: AN has consultant fee from Nippon Kayaku Co. Ltd., Speakers bureau: AN has received speaker’s fee from AbbVie Japan GK, Actelion Pharmaceuticals Japan LTD., Asahi Kasei Pharma Co., Astellas Pharma Inc., Ayumi Pharmaceutical Co., Bristol Myers Squibb Co., Ltd., Chugai Pharmaceutical Co., Ltd., Eisai Co., Ltd., Eli Lilly Japan K.K., GlaxoSmithKline K.K., Hisamitsu Pharmaceutical Co. Inc., Kyorin Pharmaceutical Co. Ltd., Mitsubishi Tanabe Pharma Co., Otsuka Pharmaceutical Co. Ltd., Pfizer Japan Inc., and Teijin Pharma Ltd.

P836Glasgow Prognostic Score predicts the readmission caused by acute decompensated heart failure after myocardial infarction

Purpose

The Glasgow Prognostic Score (GPS), combination of C-reactive protein (CRP) and serum albumin concentration, provides predictions of prognosis in patients with heart failure. We evaluated the GPS of patients with acute myocardial infarction (MI).

Methods

We investigated the prognosis of 1182 patients with acute MI in our institution. These patients were classified into three groups by GPS at admission. GPS was defined as follows: patients with both elevated CRP (>1.0mg/dL) and hypoalbuminemia (<3.5 g/dL) were allocated a score of 2, patients with only one of these biochemical abnormalities were allocated a score of 1, and patients with neither of these abnormalities were allocated a score of 0.

Results

Of the patients, 70.3% (n=831), 19.2% (n=227), and 10.5% (n=124) had GPS of 0, 1, and 2, respectively. In-hospital mortality of GPS 0, GPS 1, and GPS 2 were 4.7%, 18.1%, and 31.5%, respectively (p<0.0001). Relative to a GPS of 0, the hazard ratios for the readmission caused by acute decompensated heart failure (ADHF) were 3.27 (95% CI: 2.04–5.18) for a GPS of 1 and 3.62 (95% CI: 1.93–6.42) for a GPS of 2 in the age- and sex- adjusted Cox proportional hazard model. After propensity score matching, baseline characteristics were balanced, and 250 paired patients constituted GPS 0 group and GPS 1–2 group. Patients with GPS1 or 2 had a higher risk of the development of ADHF compared with patients with GPS 0 (Hazard ratio: 1.96, 95% confidence interval: 1.13–3.47, p=0.017).

Conclusions

The GPS, which is based on systemic inflammation, is useful for predicting the development of acute decompensated heart failure after myocardial infarction.

Ion-production efficiency of a singly charged ion source developed toward a 11C irradiation facility for cancer therapy

The ion-production efficiency of a newly developed singly charged ion source (SCIS) has been investigated to discuss the possibility of it being used in an isotope separation on-line system that provides ¹¹C ions for heavy-ion cancer therapy with simultaneous verification of the irradiation field using positron emission tomography. The SCIS uses a low-energy hollow electron beam to produce singly charged carbon ions efficiently. To deliver sufficient ¹¹C ions to the treatment room from a limited amount of ¹¹C molecules, which are produced from a boron compound target and proton-beam irradiation via the ¹¹B(p,n)¹¹C reaction, the SCIS must have high ion-production efficiency. To realize this high efficiency, the SCIS was designed using a three-dimensional particle-in-cell code in previous work. With the fabricated SCIS, we performed experiments to measure the efficiency of producing CO₂ ⁺ ions from nonradioactive ¹²CO₂ molecules and C⁺ ions from nonradioactive ¹²CH₄ molecules. We found that the SCIS achieved efficiencies of ε_C⁺ =4×10^-3 (0.4%) for C⁺ production and ε_{CO2 ⁺} =0.107 (10.7%) for CO₂ ⁺ production.

Singly charged ion source designed using three-dimensional particle-in-cell method

A singly charged ion source (SCIS) has been designed using a newly developed three-dimensional particle-in-cell (PIC) code. The SCIS is to be used in an isotope separation on-line (ISOL) system that provides ¹¹C ions for heavy-ion cancer therapy with simultaneous verification of the dose distribution using positron emission tomography. The SCIS uses low-energy electron beams to produce singly charged carbon ions efficiently and maintain a high vacuum in the ISOL system. Because the SCIS has to realize a production efficiency of 1% if its carbon ions are to be used in the ISOL system, a suitable design for the SCIS was investigated by using the developed PIC code to study the beam trajectories of the electrons and extracted ions. The simulation results show that hollow electron beams are produced in the designed SCIS resulting in a high effective electron current. The results also predict that the designed SCIS would realize ion-production efficiencies (IPEs) of ε _SCIS ≃ 6.7% for C O 2 + production from CO₂ gas and ε _SCIS ≃ 0.1% for C⁺ production from CH₄ gas. Moreover, to examine the validity of the developed code and confirm that the SCIS was able to be designed appropriately, the space-charge-limited current of the electron gun and the total IPE obtained by adding the IPEs of each ion were compared between the experiment and the simulation.

Sandwich ELISA Using a Mouse/Human Chimeric CSLEX-1 Antibody

BACKGROUND

An assay using a mouse antisialyl Lewis X (sLeX) antibody (CSLEX-1) is used clinically for screening and monitoring patients with breast cancer in Japan. However, the IgM isoform of CSLEX-1 is not preferred for the assay because the bulkiness of IgM generally causes poor accessibility to the antigen. To solve this problem, we developed an antisLeX mouse/human chimeric IgG antibody, CH-CSLEX-1, using transgenic silkworms. The performance of a homologous sandwich ELISA of CH-CSLEX1 was then evaluated.

METHODS

To generate CH-CSLEX-1, we used a GAL4/UAS binary gene expression system in transgenic silkworms. The reactivities of CSLEX-1 and CH-CSLEX-1 were determined in a Biacore analysis. To confirm antigen specificity, 3 antigens [sLeX, sLeA, and Lewis Y (LeY)] were used.

RESULTS

CH-CSLEX-1 formed correctly as an IgG class of immunoglobulin molecule with an isoelectric point close to the predicted value. The best combination for capturing and probing in a sandwich ELISA was determined as a homologous combination of CH-CSLEX-1. The CH-CSLEX-1 assay specifically detected sLeX, but not sLeA and LeY. A correlation analysis with 107 human samples showed good concordance between the conventional CSLEX-1 assay (homologous sandwich ELISA using CSLEX-1) and the CH-CSLEX-1 assay (r = 0.98). Moreover, the CH-CSLEX-1 assay was not affected by either human antimouse IgG antibodies (HAMA IgG) or HAMA IgM.

CONCLUSIONS

The mouse/human chimeric antibody CH-CSLEX-1 allowed the establishment of a highly specific sandwich ELISA for sLeX that was not affected by HAMA.

A singly charged ion source for radioactive ¹¹C ion acceleration

A new singly charged ion source using electron impact ionization has been developed to realize an isotope separation on-line system for simultaneous positron emission tomography imaging and heavy-ion cancer therapy using radioactive (11)C ion beams. Low-energy electron beams are used in the electron impact ion source to produce singly charged ions. Ionization efficiency was calculated in order to decide the geometric parameters of the ion source and to determine the required electron emission current for obtaining high ionization efficiency. Based on these considerations, the singly charged ion source was designed and fabricated. In testing, the fabricated ion source was found to have favorable performance as a singly charged ion source.

Early tissue reaction in the tension zone of PDL during orthodontic tooth movement

OBJECTIVE

The aim of the study was to examine the early tissue reaction in the tension zone of periodontal ligament (PDL) during orthodontic tooth movement.

DESIGN

Upper first molars of rats were moved buccally with fixed appliances. The PDL in the tension zone was examined histologically, immunohistochemically and at a molecular level after 24h, 3 days and 7 days.

RESULTS

After 24h of orthodontic force loading, the periodontal space appeared considerably expanded. The periodontal fibers were stretched between the bone and the root. Three days after loading, the expanded periodontal space had slightly narrowed, the periodontal fiber arrangement was relaxed, and the blood vessels did not appear elongated. A considerable layer of osteoid was formed on the bone surface. The total cross-sectional areas of the PDL in experimental groups were significantly larger than control group. The total cross-sectional areas of the blood vessels were not significantly different among the groups. Significantly high expressions of IL-1β and PTX3 were characteristically observed not only in the endothelial cells and cells around the blood vessel, but also in fibroblasts throughout the PDL of the tension zone 24h after orthodontic force loading. Three and 7 days after loading, these showed tendencies to return to control levels.

CONCLUSIONS

The present results suggest that the early reaction in the tension zone of the PDL during tooth movement consists of two phases: first, inflammation and second, rapid recovery and renovation of the PDL with bone formation.

Cryogenic molecular separation system for radioactive (11)C ion acceleration

A (11)C molecular production/separation system (CMPS) has been developed as part of an isotope separation on line system for simultaneous positron emission tomography imaging and heavy-ion cancer therapy using radioactive (11)C ion beams. In the ISOL system, (11)CH4 molecules will be produced by proton irradiation and separated from residual air impurities and impurities produced during the irradiation. The CMPS includes two cryogenic traps to separate specific molecules selectively from impurities by using vapor pressure differences among the molecular species. To investigate the fundamental performance of the CMPS, we performed separation experiments with non-radioactive (12)CH4 gases, which can simulate the chemical characteristics of (11)CH4 gases. We investigated the separation of CH4 molecules from impurities, which will be present as residual gases and are expected to be difficult to separate because the vapor pressure of air molecules is close to that of CH4. We determined the collection/separation efficiencies of the CMPS for various amounts of air impurities and found desirable operating conditions for the CMPS to be used as a molecular separation device in our ISOL system.

Electron string ion sources for carbon ion cancer therapy accelerators

The type of the Electron String Ion Sources (ESIS) is considered to be the appropriate one to produce pulsed C(4+) and C(6+) ion beams for cancer therapy accelerators. In fact, the new test ESIS Krion-6T already now provides more than 10(10) C(4+) ions per pulse and about 5 × 10(9) C(6+) ions per pulse. Such ion sources could be suitable to apply at synchrotrons. It has also been found that Krion-6T can provide more than 10(11) C(6+) ions per second at the 100 Hz repetition rate, and the repetition rate can be increased at the same or larger ion output per second. This makes ESIS applicable at cyclotrons as well. ESIS can be also a suitable type of ion source to produce the (11)C radioactive ion beams. A specialized cryogenic cell was experimentally tested at the Krion-2M ESIS for pulse injection of gaseous species into the electron string. It has been shown in experiments with stable methane that the total conversion efficiency of methane molecules to C(4+) ions reached 5%÷10%. For cancer therapy with simultaneous irradiation and precise dose control (positron emission tomography) by means of (11)C, transporting to the tumor with the primary accelerated (11)C(4+) beam, this efficiency is preliminarily considered to be large enough to produce the (11)C(4+) beam from radioactive methane and to inject this beam into synchrotrons.

A novel dual ex vivo lung perfusion technique improves immediate outcomes in an experimental model of lung transplantation

The lungs are dually perfused by the pulmonary artery and the bronchial arteries. This study aimed to test the feasibility of dual-perfusion techniques with the bronchial artery circulation and pulmonary artery circulation synchronously perfused using ex vivo lung perfusion (EVLP) and evaluate the effects of dual-perfusion on posttransplant lung graft function. Using rat heart-lung blocks, we developed a dual-perfusion EVLP circuit (dual-EVLP), and compared cellular metabolism, expression of inflammatory mediators, and posttransplant graft function in lung allografts maintained with dual-EVLP, standard-EVLP, or cold static preservation. The microvasculature in lung grafts after transplant was objectively evaluated using microcomputed tomography angiography. Lung grafts subjected to dual-EVLP exhibited significantly better lung graft function with reduced proinflammatory profiles and more mitochondrial biogenesis, leading to better posttransplant function and compliance, as compared with standard-EVLP or static cold preservation. Interestingly, lung grafts maintained on dual-EVLP exhibited remarkably increased microvasculature and perfusion as compared with lungs maintained on standard-EVLP. Our results suggest that lung grafts can be perfused and preserved using dual-perfusion EVLP techniques that contribute to better graft function by reducing proinflammatory profiles and activating mitochondrial respiration. Dual-EVLP also yields better posttransplant graft function through increased microvasculature and better perfusion of the lung grafts after transplantation.

Effect of secondary particles on image quality of dynamic flat panels in carbon ion scanning beam treatment

OBJECTIVE

Real-time markerless tumour tracking using radiographic fluoroscopic imaging is one of the better solutions to improving respiratory-gated radiotherapy. However, particle beams cause secondary particles from patients, which could affect radiographs. Here, we evaluated the quality of radiographs during carbon ion pencil beam scanning (CPBS) irradiation for respiratory gating.

METHODS

A water phantom and chest phantom were used. The phantoms were irradiated with CPBS at 290 MeV n(-1) from orthogonal directions. Dose rates were 3.4 × 10(8), 1.14 × 10(8) and 3.79 × 10(7) particles per second. A dynamic flat panel detector (DFPD) was installed on the upstream (DFPD1) or downstream (DFPD2) side of the vertical irradiation port. DFPD images were acquired during CPBS at 15.00, 7.50 and 3.75 frames per second (fps). Charge on the DFPD was cleaned using fast readout technique every 30 fps. DFPD images were acquired during CPBS with radiographic exposure, and results with and without fast readout technique were compared.

RESULTS

Secondary particles were visualized as spots or streak-like shapes. Capture of secondary particles from the horizontal beam direction was lower with fast readout technique than without it. With regard to beam irradiation direction dependency, CPBS from the horizontal direction resulted in a greater magnitude of secondary particles reaching DFPD2 than reaching DFPD1. When CPBS was delivered from the vertical direction, however, the magnitude of secondary particles on both DFPDs was very similar.

CONCLUSION

Fast readout technique minimized the effect of secondary particles on DFPD images during CPBS.

ADVANCES IN KNOWLEDGE

This technique may be useful for markerless tumour tracking for respiratory gating.

Implementation of a target volume design function for intrafractional range variation in a particle beam treatment planning system

OBJECTIVE

Treatment planning for charged particle therapy in the thoracic and abdominal regions should take account of range uncertainty due to intrafractional motion. Here, we developed a design tool (4Dtool) for the target volume [field-specific target volume (FTV)], which accounts for this uncertainty using four-dimensional CT (4DCT).

METHODS

Target and normal tissue contours were input manually into a treatment planning system (TPS). These data were transferred to the 4Dtool via the picture archiving and communication system (PACS). Contours at the reference phase were propagated to other phases by deformable image registration. FTV was calculated using 4DCT on the 4Dtool. The TPS displays FTV contours using digital imaging and communications in medicine files imported from the PACS. These treatment parameters on the CT image at the reference phase were then used for dose calculation on the TPS. The tool was tested in single clinical case randomly selected from patients treated at our centre for lung cancer.

RESULTS

In this clinical case, calculation of dose distribution with the 4Dtool resulted in the successful delivery of carbon-ion beam at the reference phase of 95% of the prescribed dose to the clinical target volume (CTV). Application to the other phases also provided sufficient dose to the CTV.

CONCLUSION

The 4Dtool software allows the design of the target volume with consideration to intrafractional range variation and is now in routine clinical use at our institution.

ADVANCES IN KNOWLEDGE

Our alternative technique represents a practical approach to four-dimensional treatment planning within the current state of charged particle therapy.

Phase III placebo-controlled double-blind randomized trial of radiotherapy for stage IIB-IVA cervical cancer with or without immunomodulator Z-100: a JGOG study

BACKGROUND

Based on the result of our previous study showing better overall survival (OS) at the lower dose (0.2 µg) of immunomodulator Z-100 than higher dose (40 µg) in patients with locally advanced cervical cancer who received radiotherapy, we conducted a placebo-controlled double-blind randomized trial.

PATIENTS AND METHODS

Patients of stages IIB-IVA squamous cell carcinoma of the uterine cervix were randomly assigned to receive Z-100 at 0.2 µg (Z) or placebo (P). The study agent was given subcutaneously twice a week during the radiotherapy, followed by maintenance therapy by administering once every 2 weeks until disease progression. Primary end point was OS, and secondary end points were recurrence-free survival, and toxicity.

RESULTS

A total of 249 patients were randomized. Death events occurred extremely slower than expected, and Independent Data Monitoring Committee recommended to analyze the survival result prematurely. The 5-year OS rate was 75.7% [95% confidence interval (CI) 66.4% to 82.8%] for Arm Z and 65.8% (95% CI 56.2% to 73.8%) for Arm P (P = 0.07); hazard ratio was 0.65 (95% CI 0.40-1.04). Survival benefit in Arm Z was observed regardless of chemoradiation or radiation alone. There was no trend in recurrence-free survival between the two arms. Side-effects were not different between two arms.

CONCLUSION

Z-100 showed a trend of improvement on OS in locally advanced cervical cancer, although the statistical power was less than anticipated because survival rates were unexpectedly higher than expected for both arms. Validation of potential survival benefit of immune modulation should be made.

TRIAL REGISTRATION

umin.ac.jp/ctr Identifier: C000000221.

Status of a compact electron cyclotron resonance ion source for National Institute of Radiological Sciences-930 cyclotron

The Kei-source is a compact electron cyclotron resonance ion source using only permanent magnets and a frequency of 10 GHz. It was developed at the National Institute of Radiological Sciences (NIRS) for producing C(4+) ions oriented for high-energy carbon therapy. It has also been used as an ion source for the NIRS-930 cyclotron. Its microwave band region for the traveling-wave-tube amplifier and maximum output power are 8-10 GHz and 350 W, respectively. Since 2006, it has provided various ion beams such as proton, deuteron, carbon, oxygen, and neon with sufficient intensity (200 μA for proton and deuteron, 50 μA for C(4+), for example) and good stability for radioisotope production, tests of radiation damage, and basic research experiments. Its horizontal and vertical emittances were measured using a screen monitor and waist-scan. The present paper reports the current status of the Kei-source.