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Three-dimensional pseudo-continuous arterial spin-labelled perfusion imaging for diagnosing upper cervical lymph node metastasis in patients with nasopharyngeal carcinoma: a whole-node histogram analysis. Clin Radiol 2024; 79:e736-e743. [PMID: 38341343 DOI: 10.1016/j.crad.2024.01.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 01/11/2024] [Accepted: 01/16/2024] [Indexed: 02/12/2024]
Abstract
AIM To evaluate whole-node histogram parameters of blood flow (BF) maps derived from three-dimensional pseudo-continuous arterial spin-labelled (3D pCASL) imaging in discriminating metastatic from benign upper cervical lymph nodes (UCLNs) for nasopharyngeal carcinoma (NPC) patients. MATERIALS AND METHODS Eighty NPC patients with a total of 170 histologically confirmed UCLNs (67 benign and 103 metastatic) were included retrospectively. Pre-treatment 3D pCASL imaging was performed and whole-node histogram analysis was then applied. Histogram parameters and morphological features, such as minimum axis diameter (MinAD), maximum axis diameter (MaxAD), and location of UCLNs, were assessed and compared between benign and metastatic lesions. Predictors were identified and further applied to establish a combined model by multivariate logistic regression in predicting the probability of metastatic UCLNs. Receiver operating characteristic (ROC) curves were used to analyse the diagnostic performance. RESULTS Metastatic UCLNs had larger MinAD and MinAD/MaxAD ratio, greater energy and entropy values, and higher incidence of level II (upper jugular group), but lower BF10th value than benign nodes (all p<0.05). MinAD, BF10th, energy, and entropy were validated as independent predictors in diagnosing metastatic UCLNs. The combined model yielded an area under the curve (AUC) of 0.932, accuracy of 84.42 %, sensitivity of 80.6 %, and specificity of 90.29 %. CONCLUSIONS Whole-node histogram analysis on BF maps is a feasible tool to differentiate metastatic from benign UCLNs in NPC patients, and the combined model can further improve the diagnostic efficacy.
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Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A. PHYSICAL REVIEW LETTERS 2024; 132:131002. [PMID: 38613275 DOI: 10.1103/physrevlett.132.131002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 01/23/2024] [Accepted: 02/12/2024] [Indexed: 04/14/2024]
Abstract
We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15 PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.
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[Preliminary study on automatic quantification and grading of leopard spots fundus based on deep learning technology]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 2024; 60:257-264. [PMID: 38462374 DOI: 10.3760/cma.j.cn112142-20231210-00281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Objective: To achieve automatic segmentation, quantification, and grading of different regions of leopard spots fundus (FT) using deep learning technology. The analysis includes exploring the correlation between novel quantitative indicators, leopard spot fundus grades, and various systemic and ocular parameters. Methods: This was a cross-sectional study. The data were sourced from the Beijing Eye Study, a population-based longitudinal study. In 2001, a group of individuals aged 40 and above were surveyed in five urban communities in Haidian District and three rural communities in Daxing District of Beijing. A follow-up was conducted in 2011. This study included individuals aged 50 and above who participated in the second 5-year follow-up in 2011, considering only the data from the right eye. Color fundus images centered on the macula of the right eye were input into the leopard spot segmentation model and macular detection network. Using the macular center as the origin, with inner circle diameters of 1 mm, 3 mm, and outer circle diameter of 6 mm, fine segmentation of the fundus was achieved. This allowed the calculation of the leopard spot density (FTD) and leopard spot grade for each region. Further analyses of the differences in ocular and systemic parameters among different regions' FTD and leopard spot grades were conducted. The participants were categorized into three refractive types based on equivalent spherical power (SE): myopia (SE<-0.25 D), emmetropia (-0.25 D≤SE≤0.25 D), and hyperopia (SE>0.25 D). Based on axial length, the participants were divided into groups with axial length<24 mm, 24-26 mm, and>26 mm for the analysis of different types of FTD. Statistical analyses were performed using one-way analysis of variance, Kruskal-Wallis test, Bonferroni test, and Spearman correlation analysis. Results: The study included 3 369 participants (3 369 eyes) with an average age of (63.9±10.6) years; among them, 1 886 were female (56.0%) and 1, 483 were male (64.0%). The overall FTD for all eyes was 0.060 (0.016, 0.163); inner circle FTD was 0.000 (0.000, 0.025); middle circle FTD was 0.030 (0.000, 0.130); outer circle FTD was 0.055 (0.009, 0.171). The results of the univariate analysis indicated that FTD in various regions was correlated with axial length (overall: r=0.38, P<0.001; inner circle: r=0.31, P<0.001; middle circle: r=0.36, P<0.001; outer circle: r=0.39, P<0.001), subfoveal choroidal thickness (SFCT) (overall: r=-0.69, P<0.001; inner circle: r=-0.57, P<0.001; middle circle: r=-0.68, P<0.001; outer circle: r=-0.72, P<0.001), age (overall: r=0.34, P<0.001; inner circle: r=0.30, P<0.001; middle circle: r=0.31, P<0.001; outer circle: r=0.35, P<0.001), gender (overall: r=-0.11, P<0.001; inner circle: r=-0.04, P<0.001; middle circle: r=-0.07, P<0.001; outer circle: r=-0.11, P<0.001), SE (overall: r=-0.20; P<0.001; inner circle: r=-0.19, P<0.001; middle circle: r=-0.20, P<0.001; outer circle: r=-0.20, P<0.001), uncorrected visual acuity (overall: r=-0.18, P<0.001; inner circle: r=-0.26, P<0.001; middle circle: r=-0.24, P<0.001; outer circle: r=-0.22, P<0.001), and body mass index (BMI) (overall: r=-0.11, P<0.001; inner circle: r=-0.13, P<0.001; middle circle: r=-0.14, P<0.001; outer circle: r=-0.13, P<0.001). Further multivariate analysis results indicated that different region FTD was correlated with axial length (overall: β=0.020, P<0.001; inner circle: β=-0.022, P<0.001; middle circle: β=0.027, P<0.001; outer circle: β=0.022, P<0.001), SFCT (overall: β=-0.001, P<0.001; inner circle: β=-0.001, P<0.001; middle circle: β=-0.001, P<0.001; outer circle: β=-0.001, P<0.001), and age (overall: β=0.002, P<0.001; inner circle: β=0.001, P<0.001; middle circle: β=0.002, P<0.001; outer circle: β=0.002, P<0.001). The distribution of overall (H=56.76, P<0.001), inner circle (H=72.22, P<0.001), middle circle (H=75.83, P<0.001), and outer circle (H=70.34, P<0.001) FTD differed significantly among different refractive types. The distribution of overall (H=373.15, P<0.001), inner circle (H=367.67, P<0.001), middle circle (H=389.14, P<0.001), and outer circle (H=386.89, P<0.001) FTD differed significantly among different axial length groups. Furthermore, comparing various levels of FTD with systemic and ocular parameters, significant differences were found in axial length (F=142.85, P<0.001) and SFCT (F=530.46, P<0.001). Conclusions: The use of deep learning technology enables automatic segmentation and quantification of different regions of theFT, as well as preliminary grading. Different region FTD is significantly correlated with axial length, SFCT, and age. Individuals with older age, myopia, and longer axial length tend to have higher FTD and more advanced FT grades.
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[Emphasizing the timing and procedure selection for vitrectomy in pathological myopic traction maculopathy]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 2024; 60:211-214. [PMID: 38462367 DOI: 10.3760/cma.j.cn112142-20231221-00299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Myopic maculopathy is the primary cause of irreversible visual impairment in patients with pathologic myopia, and myopic traction maculopathy often requires vitrectomy for treatment. Myopic traction maculopathy encompasses epiretinal membrane, foveoschisis, macular hole, and macular hole-related retinal detachment. It is recommended to perform vitrectomy combined with inner limiting membrane peeling for Type II epiretinal membrane, foveal-sparing inner limiting membrane peeling for foveoschisis, inverted inner limiting membrane flap technique for macular hole, and vitrectomy combined with macular buckle for refractory macular hole-related retinal detachment. Myopic traction maculopathy is a chronically progressive condition, and surgeons need to accurately determine the timing of surgery and choose appropriate procedures to maximize the benefits for patients.
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[Research progress on pathogenesis of thrombocytopenia associated with TAVI]. ZHONGHUA XIN XUE GUAN BING ZA ZHI 2024; 52:205-209. [PMID: 38326074 DOI: 10.3760/cma.j.cn112148-20231007-00211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
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Measurement of Ultra-High-Energy Diffuse Gamma-Ray Emission of the Galactic Plane from 10 TeV to 1 PeV with LHAASO-KM2A. PHYSICAL REVIEW LETTERS 2023; 131:151001. [PMID: 37897763 DOI: 10.1103/physrevlett.131.151001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 07/08/2023] [Accepted: 08/18/2023] [Indexed: 10/30/2023]
Abstract
The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, propagation, and interaction of cosmic rays in the Milky Way. In this Letter, we report the measurements of diffuse γ rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner (15°10 TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of -2.99±0.04, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of ∼3 than the prediction. A similar spectrum with an index of -2.99±0.07 is found in the outer Galaxy region, and the absolute flux for 10≲E≲60 TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations.
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Evaluation of Treatment Interruptions and Recovery during Biology-Guided Radiotherapy Delivery. Int J Radiat Oncol Biol Phys 2023; 117:e722-e723. [PMID: 37786107 DOI: 10.1016/j.ijrobp.2023.06.2233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) A Biology-guided Radiotherapy (BgRT) based device is designed to use Positron Emission Tomography (PET) signals to achieve tracked dose delivery. The goal of this study is to investigate the dose delivery accuracy in case of interruption during BgRT treatment, and resumption in a separate treatment session for a multi-target delivery, as the PET activity continues to decay. MATERIALS/METHODS A custom-built large anthropomorphic phantom (LAP) including a 26 mm spherical target with 3D independent motion and two 22 mm spherical targets with 1D sinusoidal motion embedded in water was used. All three targets were filled with FGD in an 8:1 target to background uptake ratio (41.52 kBq/ml in target and 5.19 kBq/ml in background). During BgRT delivery, the treatment was intentionally paused during delivery to the second target and the current treatment session was ended to generate a partial fraction. Then the partial fraction was continued in a new session, where the CT scan localization and PET pre-scan were repeated using the existing PET activity present in the phantom. The newly acquired PET pre-scan, was then used to determine if sufficient PET counts were present to resume treatment delivery. The interruption and recovery algorithm is designed to calculate the fluence that needs to be delivered to the remaining targets as well as the residual fluence to be given to the targets that have already received partial dose prior to the interruption. Once the new fluence is recomputed, the treatment is resumed. The delivered doses were captured using radiochromic film (EBT-XD) inserted in the target as well as post-treatment dose calculations based on the delivered beamlet sequence to evaluate the results in terms of dosimetric coverage and margin loss. The margin loss is calculated as the maximum difference between the distance from the Clinical Target Volume (CTV) contour to the 97% isodose contour in the treatment plan and the on the film. The dosimetric coverage is defined as the percentage of voxels within the CTV that lies within 97% and 130% of the prescribed dose. RESULTS As shown in the table below, a margin loss of less than 3 mm for all targets and 100% CTV coverage was achieved. After treatment interruptions, the PET safety evaluation based on the PET pre-scan helped to determine whether the treatment could be continued on the same day using the same injected PET activity (an NTS value ≧ 2 and AC value ≧ 5 kBq/ml). CONCLUSION This study demonstrated that the BgRT system is able to deliver the prescribed dose to all targets with independent motion, even when an interruption and resumption occurs during treatment. In case such an interruption if the remaining PET activity satisfies the BgRT safety evaluation, the treatment can continue to deliver the remainder of the BgRT doses.
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Intrafraction Dosimetric Evaluation of Biology-Guided Radiotherapy to a Target Under Respiratory Motion. Int J Radiat Oncol Biol Phys 2023; 117:e680-e681. [PMID: 37786004 DOI: 10.1016/j.ijrobp.2023.06.2141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) To evaluate the reproducibility and variability of biology-guided radiotherapy (BgRT) treatments using a large anthropomorphic phantom modeling the motion amplitude of a lung tumor. MATERIALS/METHODS RefleXion X1 is equipped with two opposing 90 degrees PET detector arcs to capture the radionuclide emissions and direct the 6MV Linac to treat the lesions in real time. A custom-built phantom filled with a liquid [¹⁸F]Fluorodeoxyglucose (FDG) solution was used. Fillable target and OAR structures were 3D printed and attached to motion stages. The GTV = CTV was matched to the spherical 22 mm diameter target, and the PTV was a 5 mm expansion from the CTV volume. The Biology Tracking Zone (BTZ) was generated after adding 5 mm margin to the motion extent of the CTV. The OAR was a large C-shape annulus (emulating a heart) that was approximately 3 cm from the target. The 3D independent motion trajectory of the target was designed to mimic lung motion: range of +5.8 mm to -4.9 mm in LR, range of +14.4 mm to -11.3 mm in SI, and range of +5.2 mm to -5.1 mm in AP directions. The OAR motion waveform used a 1D sinusoidal pattern with a 5 mm amplitude in SI direction. The target and the OAR were filled with 40 kBq/mL while the background had 5 kBq/mL FDG. A BgRT Modeling (imaging-only) PET acquisition was performed using RefleXion X1 and used to generate a 4-fraction BgRT treatment plan prescribing 10 Gy/fraction to PTV. For each delivery, target, OAR and background were filled with the same FDG concentrations as in the BgRT Modeling PET planning scan. Dosimetry to the target and OAR were both measured using an ion-chamber (Exradin A14SL) and film in the coronal plane through the center of the GTV for all 4 fractions. RESULTS The mean activity concentration within the (BTZ) was 7.4 ± 0.8 kBq/mL. The calculated signal-to-noise ratio metric (Normalized Target Signal) within the BTZ was 4.0 ± 0.3. Total treatment times were all less than 35 minutes (34.3 ± 0.2). Prescription dose coverage to the CTV for all 4 fractions was 100%. Ion chamber measurements in the CTV were -1.6 ± 1.3% relative to the planned dose over the active area of the ion-chamber. Minimum and maximum doses to the CTV, measured on film, were -7.7 ± 2.2% and 1.3 ± 1.4%, calculated relative to the planned dose distribution, respectively. The OAR maximum point dose measured on film was -8.7 ± 2.9%, calculated relative to the maximum OAR dose predicted on the bounded dose-volume histogram. CONCLUSION Based on this initial study, accurate and reproducible dosimetry can be achieved for targets under respiratory motion using biology-guided radiotherapy over the course of a complete course of treatment. Further studies are needed to evaluate the intrafraction dosimetry of BgRT delivery under various motion models and tumor sizes.
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Dosimetric Accuracy of Multi-Target Biology-Guided Radiotherapy Treatments in a Single Session. Int J Radiat Oncol Biol Phys 2023; 117:e722. [PMID: 37786108 DOI: 10.1016/j.ijrobp.2023.06.2232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) We present the first dosimetric measurements of single session, multi-target BgRT deliveries using a clinically realistic motion phantom on a research-only version of the RefleXion X1 system. MATERIALS/METHODS A custom-made anthropomorphic phantom of a human torso with embedded fillable targets mimicking 18F-FDG-avid lesions was used. From the three embedded spherical targets, Target 1 was 26 mm in diameter coupled with a 3D independent respiratory motion with 22 mm range, whereas Target 2 and 3 were 22 mm in diameter and moved with a 1D 5 mm maximum sinusoidal motion. The 18F-FDG concentration in the background cavity of the phantom was 5 kBq/ml, and the targets were loaded with 10:1, 8:1 and 6:1 contrast relative to the background for Targets 1, 2, 3, respectively. Spherical structures were contoured as GTVs (CTV = GTV) and a 5 mm margin was added to create PTVs. Motion extent of the tumors were captured to create biological tracking zones for each target. Treatment plans were generated using a research version of the Reflexion treatment planning software to deliver 8 Gy/fx to the PTVs. The treatment delivery was repeated 2 times, and each time the phantom was refilled according to the plan. PET image evaluation metrics for each of the three targets were also recorded. Target dosimetry was measured using a combination of radiographic film and ion chamber. The maximum distance between the 97% prescription isodose line from the plan and the film measurements was used to characterize the dosimetric accuracy of the tracked deliveries. CTV and PTV min, max, and mean doses measured on film were also recorded for each target. RESULTS Treatment plans were successfully created with 100% prescription dose coverage to each target loaded with different FDG ratios. Total treatment times for the single-plan, three-target deliveries were less than 80 minutes. PET evaluation metrics at imaging-only and pre-scan, and planning and film dosimetry to the GTV and PTV for each of the three targets is shown in table below (mean ± standard deviation of both deliveries). The CTV dose coverage was maintained for all targets. The shrinkage distance of the 97% prescription dose isodose line on the film plane for all three targets was less than 3 mm for both tests, and ranged from -0.4 to -2.34 mm. CONCLUSION These results demonstrate that high tracking accuracy and dosimetric accuracy can be achieved in single session, multi-target deliveries over a range of target-to-background 18F-FDG concentrations and target motion patterns.
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Treatment Plan Creation and Delivery with and without BgRT for Static and Motion Trajectories. Int J Radiat Oncol Biol Phys 2023; 117:e697-e698. [PMID: 37786043 DOI: 10.1016/j.ijrobp.2023.06.2179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) In this work we try to validate the motion tracking capabilities of BgRT for periodic and step motion trajectories. SBRT plans that matches the corresponding BgRT plans are created and delivered to the same phantom with and without motion and results are evaluated. Using BgRT based SBRT plans eliminates any user bias and creates SBRT plans that would represent treatment delivery scenarios that could have happened if the PET guided BgRT was not present for that treatment. MATERIALS/METHODS To validate SBRT plans that matches the BgRT plans, we used three different types of motion patterns (1) static, (2) lung tumor motion and (3) one-centimeter step-shift. The lung tumor motion (∼25 mm in IEC-Y, ∼7 mm in IEC-X and ∼ 10 mm in IEC-Z) was used as it represents a continuous motion of the target for the entire length of the study while the step-shift case corresponds to the patient or tumor shifting between the localization CT and the start of treatment. First, a 10 Gy per fraction BgRT plan was created for each of the three experiments based on the corresponding PET image. Then, the BgRT plans were delivered to the corresponding targets with and without motion and results are evaluated. To perform a comparative study that assess the performance of BgRT and traditional SBRT (planning and delivery methods), the exact same plan fluence of BgRT plan for each experiment was used to create the corresponding SBRT plans. The newly created SBRT plans were delivered to the corresponding phantom experiments and were compared against BgRT delivery in terms of dose coverage and target margin loss using radiochromic film that moves with the target. The margin loss was calculated as the difference between the distance from the CTV contour to the 97% isodose contour in the treatment plan and the CTV contour to the 97% isodose contour on the film. Dosimetric coverage was on the other hand calculated as the percentage of the voxels within the CTV that lies within 97% and 130% of the prescribed dose. RESULTS The results showed that the margin loss for BgRT is less than 3 mm, while for the SBRT plans were more than 3 mm when target motion is present. The dosimetric coverage for BgRT was 100% for all three cases, however less than 100% for the SBRT cases with motion. Table showing margin loss for the various experiments for a prescription dose of 10 Gy. CONCLUSION The results shows that BgRT is capable of tracking the tumor motion and delivering the prescribed dose to the moving target.
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Characterization of Biology-Guided Radiotherapy Accuracy as a Function of PET Tracer Uptake. Int J Radiat Oncol Biol Phys 2023; 117:e668-e669. [PMID: 37785972 DOI: 10.1016/j.ijrobp.2023.06.2113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) To characterize the tracking capability and dosimetric accuracy of biology-guided radiotherapy (BgRT) under clinically relevant PET tracer uptake scenarios relative to the background. MATERIALS/METHODS A custom-made anthropomorphic phantom filled with a liquid 18F-FDG solution including two embedded fillable 22 mm diameter spherical structures mimicking GTV (= CTV) and OAR was coupled to motion stages to create an independent 3D respiratory motion with 22 mm maximum range for target and a 5 mm 1D sinusoidal motion in the OAR. The biology-tracking zone (BTZ) was generated by adding 5 mm margin to the motion extent. The three BgRT scenarios studied were representative of tumors with good (8:1), borderline (4:1) and undesired (2:1) PET biodistributions compared to background. The clinical safety limit of BgRT uses Activity Concentration within the BTZ (AC ≥ 5 kBq/ml) and Normalized Target Signal as a contrast metric (NTS ≧ 2.7 for planning and ≧ 2 for delivery). The BgRT deliveries were repeated 3 times with radiochromic film and integrated ion chamber capturing the target and OAR doses. Tracked dosimetry was assessed using a margin-loss calculation defined as the maximum linear difference in distance between the planned and delivered 97% prescription iso-dose lines. RESULTS The imaging-only PET images used to create BgRT plans had an AC of 7.0, 5.3, and 1.6 kBq/ml with an NTS of 6.8, 5.3, and 1.8 for 8:1, 4:1, and 2:1 concentrations, respectively. Qualitatively, the target was not visible on the planning PET images 2:1 loading scenario. At delivery, the mean pre-scan activity concentrations were 6.8, 4.7, and 3.7 kBq/ml with corresponding mean NTS of 3.7, 2.6, 1.5 for 8:1, 4:1 and 2:1 deliveries. The pre-scan values of AC or NTS did not satisfy the clinical system safety limits for 4:1 and 2:1 ratio experiments, but the engineering software allowed for the delivery to capture the resulting doses. The deliveries showed a prescription dose coverage to the CTV of 100% for the 8:1 and 4:1 cases, but 88% for the 2:1 case. When compared to the planned dose values, the delivered minimum doses were -7.6%, -8.6% and -10.9%, whereas the maximum dose differences in CTV were 1.2%, 0% and -4.8% of the planned dose distributions of the 8:1, 4:1 and 2:1 cases, respectively. Calculated margin losses were -2.3, -3.8, and -5.5 mm, for the 8:1, 4:1, and 2:1 cases, respectively. The maximum OAR doses were less than the maximum doses predicted on the bounded DVH curves for all scenarios. CONCLUSION With sufficient tracer uptake in the target, BgRT can deliver tracked dosimetry for targets with a large respiratory motion profile. Both the good BgRT candidate and borderline cases produced clinically acceptable delivered doses, even though the borderline case was flagged by the clinical system safety checks. As expected, the delivered BgRT dose distributions were suboptimal with reduced tumor over background PET contrast.
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[Long-term mortality risk of valvular heart disease adults over 35 years old in Chinese communities]. ZHONGHUA YI XUE ZA ZHI 2023; 103:1818-1823. [PMID: 37357186 DOI: 10.3760/cma.j.cn112137-20221118-02430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/27/2023]
Abstract
Objective: To investigate the risk and influencing factors of long-term mortality of valvular heart disease (VHD) adults aged 35 years and over in Chinese communities. Methods: A cohort study was carried out. The data of the subjects who underwent echocardiography were collected from the Chinese Hypertension Survey between 2012 and 2015 and survival outcomes were followed up between 2018 and 2019. Kaplan-Meier survival curves were plotted and compared using log-rank test. Cox proportional hazards models were used to analyze the influence of VHD on mortality. Results: During an average follow-up time of (4.6±0.9) years, a total of 23 237 participants (10 881 males and 12 356 females) were pooled into the final analysis from 5 eastern, 5 central, and 4 western provinces, cities and autonomous regions in China, with a mean age of (56.9±13.2) years. Among the included participants, 1 004 had VHD (467 males and 537 females), with a mean age was of (68.1±12.6) years. In the Kaplan-Meier analysis, participants with VHD had a significantly increased risk of all-cause mortality (log-rank χ2=351.82, P<0.001) and cardiovascular mortality (log-rank χ2=284.14, P<0.001) compared with those without VHD. Multivariate Cox regression analysis showed that compared with those without VHD, the participants with rheumatic VHD had a 45% increased risk of all-cause mortality (HR=1.45, 95%CI: 1.12-1.89) and degenerative VHD increased the risk of cardiovascular mortality by 69% (HR=1.69, 95%CI: 1.19-2.38). The risk factors of cardiovascular mortality for VHD were age 55 years and over (55-<75 years: HR=4.93, 95%CI: 1.17-20.85;≥75 years: HR=11.92, 95%CI: 2.85-49.80) and diabetes mellitus (HR=1.71, 95%CI: 1.00-2.93). Conclusions: VHD is a risk factor of all-cause mortality and cardiovascular mortality among adults aged 35 years and over. Age 55 years and over and diabetes mellitus are adverse prognostic factors for patients with VHD.
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A tera-electron volt afterglow from a narrow jet in an extremely bright gamma-ray burst. Science 2023:eadg9328. [PMID: 37289911 DOI: 10.1126/science.adg9328] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 05/25/2023] [Indexed: 06/10/2023]
Abstract
Some gamma-ray bursts (GRBs) have a tera-electron volt (TeV) afterglow, but the early onset of this has not been observed. We report observations with the Large High Altitude Air Shower Observatory of the bright GRB 221009A, which serendipitously occurred within the instrument field of view. More than 64,000 photons >0.2 TeV were detected within the first 3000 seconds. The TeV flux began several minutes after the GRB trigger, then rose to a peak about 10 seconds later. This was followed by a decay phase, which became more rapid ~650 seconds after the peak. We interpret the emission using a model of a relativistic jet with half-opening angle ~0.8°. This is consistent with the core of a structured jet and could explain the high isotropic energy of this GRB.
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[Prevalence of albuminuria and its association with cardiovascular diseases in Chinese residents aged over 35 years]. ZHONGHUA NEI KE ZA ZHI 2023; 62:290-296. [PMID: 36822855 DOI: 10.3760/cma.j.cn112138-20220328-00214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Objective: To investigate the prevalence of albuminuria in Chinese residents aged >35 years and its potential association with cardiovascular disease (CVD). Methods: A total of 34 647 Chinese subjects aged ≥35 years were selected by stratified multi-stage random sampling from 2012 to 2015. Data were collected through questionnaires, physical examinations, and laboratory tests. Albuminuria was categorized into 3 types according to urinary albumin-to- creatinine ratio: normal (<30 mg/g), microalbuminuria (MAU, 30-300 mg/g), and macroalbuminuria (≥300 mg/g). Measurement data were expressed as x¯±s, and t-tests were used for comparisons between indicators. Qualitative data were expressed as rate or constituent ratio, and the χ2 test or Kruskal-Wallis test was used to examine differences. Logistic regression was used for multivariate analyses. SAS 9.4 software was used for statistical analyses, and P<0.05 was considered statistically significant. Results: The prevalence of abnormal albuminuria was 19.1%; the prevalence was 17.2% for MAU and lower in males (13.8%) than females (20.1%, P<0.01). The risk of CVD was higher among subjects with MAU (OR=1.23, 95%CI 1.12-1.35) and macroalbuminuria (OR=1.86, 95%CI 1.50-2.32). When MAU was complicated by hypertension and diabetes mellitus, the CVD risk was 1.76 times higher. Conclusions: The prevalence of MAU is high among Chinese subjects aged 35 years and over. Those with MAU have higher CVD risk, especially those with hypertension and diabetes mellitus.
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[Current status of hypertension prevalence, treatment and control rate among young and middle-aged population in China]. ZHONGHUA XIN XUE GUAN BING ZA ZHI 2022; 50:1169-1176. [PMID: 36517437 DOI: 10.3760/cma.j.cn112148-20220916-00721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Objective: To estimate the prevalence, awareness, treatment and control rate of hypertension among young and middle-aged population in China. Methods: The analysis was based on the results of 2012-2015 China Hypertension Survey, which was a cross-sectional stratified multistage random sampling survey. A total of 229 593 subjects were included in the final analysis. The data including sex, age, living in urban and rural areas, prevalence of hypertension, history of stroke, family history of coronary heart disease and drinking, physical examination, heart rate were collected. Hypertension was defined as mean systolic blood pressure (SBP) ≥140 mmHg (1 mmHg=0.133 kPa), and (or) diastolic blood pressure (DBP) ≥90 mmHg, and (or) self-report a history of hypertension, and (or) use of antihypertensive medicine within 2 weeks before survey. Prehypertension was defined as SBP between 120-139 mmHg, and (or) DBP between 80-89 mmHg. Control of hypertension was considered for hypertensive individuals with SBP<140 mmHg and DBP<90 mmHg. The prevalence of prehypertension, hypertension, awareness, treatment, control rate were calculated, and the control rate among those with antihypertensive medication was also calculated. Results: The prevalence of prehypertension and hypertension was 43.8% (95%CI: 42.3%-45.4%), and 22.1% (95%CI: 20.8%-23.3%), respectively. The prevalence of prehypertension and hypertension was significantly higher among male than female across different age groups. The awareness, treatment, control rate of hypertension and control rate among treated hypertensive participants were 43.8%, 33.2%, 16.7%, and 40.2%, respectively. The prevalence was higher, and the control rate was lower among individuals with higher heart rate. Conclusion: The prevalence of prehypertension and hypertension among young and middle-aged population is high, the awareness, treatment and control rate need to be further improved in this population. The prevention and treatment of hypertension should be strengthened in the future to improve the control rate of hypertension in China.
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Constraints on Heavy Decaying Dark Matter from 570 Days of LHAASO Observations. PHYSICAL REVIEW LETTERS 2022; 129:261103. [PMID: 36608208 DOI: 10.1103/physrevlett.129.261103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 08/19/2022] [Accepted: 10/27/2022] [Indexed: 06/17/2023]
Abstract
The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 10^{5} and 10^{9} GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.
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Robustness of Biology-Guided Radiotherapy Delivery to PET Biodistribution Changes within Target. Int J Radiat Oncol Biol Phys 2022. [DOI: 10.1016/j.ijrobp.2022.07.2180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Reconstruction of Cherenkov image by multiple telescopes of LHAASO-WFCTA. RADIATION DETECTION TECHNOLOGY AND METHODS 2022. [DOI: 10.1007/s41605-022-00342-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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19
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1077P An updated network meta-analysis of EGFR-TKIs and combination therapy in the first-line treatment of the advanced EGFR mutation positive non-small cell lung cancer. Ann Oncol 2022. [DOI: 10.1016/j.annonc.2022.07.1203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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20
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334P Adjuvant radiotherapy improves overall survival in patients with stage T4N0-2M0 sigmoid colon cancer. Ann Oncol 2022. [DOI: 10.1016/j.annonc.2022.07.472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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21
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Search for continuous gravitational wave emission from the Milky Way center in O3 LIGO-Virgo data. Int J Clin Exp Med 2022. [DOI: 10.1103/physrevd.106.042003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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22
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Graphene-Based Optically Transparent Metasurface Capable of Dual-Polarized Modulation for Electromagnetic Stealth. ACS APPLIED MATERIALS & INTERFACES 2022; 14:31075-31084. [PMID: 35770880 DOI: 10.1021/acsami.2c04414] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Microwave stealth technology with optical transparency is of great significance for solar-powered aircrafts (e.g., satellites or unmanned aerial vehicles) in increasingly complex electromagnetic environments. By coating them with optically transparent absorbing materials or devices, these large-sized solar panels could avoid detection by radar while maintaining highly efficient collection of solar energy. However, conventional microwave-absorbing materials/devices for solar panels suffer from bulky volume and fixed stealth performance that significantly hinders their practicality or multifunctionality. Particularly, dynamic modulation of microwave absorption for dual polarization remains a challenge. In this paper, we propose the design, fabrication, and characterization of an optically transparent and dynamically tunable microwave-absorbing metasurface that enables dual modulations (amplitude and frequency) independently for two orthogonal linearly polarized excitations. The tunability of the proposed metasurface is guaranteed by an elaborately designed anisotropic meta-atom composed of a patterned graphene structure whose electromagnetic responses for different polarizations can be dynamically and independently controlled via bias voltages. The dual tunability in such a graphene-based absorbing metasurface is experimentally measured, which agrees well with those numerical results. We further build an equivalent lumped circuit model to analyze the physical relation between the tunable sheet resistance of graphene and the polarization-independent modulations of the metasurface. Taking into account the advantages of optical transparency and flexibility, the proposed microwave-absorbing metasurface significantly enhances the multitasking stealth performance in complex scenarios and has the potential for advanced solar energy devices.
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[Investigate developmental coordination disorder of kindergarten children in Zhejiang Province]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 2022; 56:838-842. [PMID: 35785866 DOI: 10.3760/cma.j.cn112150-20210719-00691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In order to investigate developmental coordination disorder (DCD) of kindergarten children in Zhejiang province, 200 ordinary kindergartens were randomly selected by stratified random sampling in 11 prefecture-level cities of Zhejiang Province, and 38 900 children from 1 000 classes in each grade were then randomly selected into the study from June 2019 to December 2019. The Little DCD Questionnaire and a self-designed questionnaire were used to screen the DCD of those children. There were 36 807 valid questionnaires, and 6.50% (2 391/36 807) of them were positive results. The results showed that boy, age ≤5 years, overweight or obesity, left handedness, comorbidity with motor or developmental disorders and premature infants were risk factors of DCD in children. As for parents and families, maternal gestational age<20 years, maternal overweight or obesity before pregnancy, low-middle level education of parents, direct family and low income of family were also associated with DCD in children. Therefore, it is necessary to conduct early prevention and intervention strategies targeting on identified risk factors among relevant population.
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All-sky, all-frequency directional search for persistent gravitational waves from Advanced LIGO’s and Advanced Virgo’s first three observing runs. Int J Clin Exp Med 2022. [DOI: 10.1103/physrevd.105.122001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Effects of aerobic exercise on inflammatory factors in healthy adults: a meta-analysis. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2022; 26:4163-4175. [PMID: 35776016 DOI: 10.26355/eurrev_202206_29053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
OBJECTIVE With this meta-analysis we aimed at systematically evaluating the intervention effects of aerobic exercise on inflammatory factors in healthy adults and identifying an optimal aerobic exercise program with anti-inflammatory effects. MATERIALS AND METHODS Four databases, including PubMed, Web of Science, Cochrane Library and SPORTDiscus, were searched from inception until April 30, 2021. Stata version 11.0 was used for data analysis. RESULTS A total of 15 studies with 1160 participants were included. The pooled estimates showed that aerobic exercise could significantly reduce TNFα levels (SMD=-0.30, 95% CI: -0.58 - -0.03, p=0.032), while the levels of IL-6 (SMD=-0.14, 95% CI: -0.32-0.03, p=0.109) and CRP (SMD=-0.09, 95% CI: -0.34-0.16, p=0.484) were not significantly affected. CONCLUSIONS Aerobic exercise exerts a positive effect by preventing inflammation-related diseases.
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Process Development and Manufacturing: CAR-T CELL EXPANSION PLATFORMS YIELD DISTINCT PHENOTYPIC AND TRANSCRIPTIONAL PROFILES. Cytotherapy 2022. [DOI: 10.1016/s1465-3249(22)00111-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Exploring Lorentz Invariance Violation from Ultrahigh-Energy γ Rays Observed by LHAASO. PHYSICAL REVIEW LETTERS 2022; 128:051102. [PMID: 35179919 DOI: 10.1103/physrevlett.128.051102] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 12/06/2021] [Accepted: 12/24/2021] [Indexed: 06/14/2023]
Abstract
Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first detection of PeV γ rays from astrophysical sources may provide a very sensitive probe of the effect of the Lorentz invariance violation (LIV), which results in decay of high-energy γ rays in the superluminal scenario and hence a sharp cutoff of the energy spectrum. Two highest energy sources are studied in this work. No signature of the existence of the LIV is found in their energy spectra, and the lower limits on the LIV energy scale are derived. Our results show that the first-order LIV energy scale should be higher than about 10^{5} times the Planck scale M_{Pl} and that the second-order LIV scale is >10^{-3}M_{Pl}. Both limits improve by at least one order of magnitude the previous results.
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Physical Confirmation of Biology-Guided Radiotherapy Directed at Static Targets With Varying Shapes and Background Contrast Environments. Int J Radiat Oncol Biol Phys 2021. [DOI: 10.1016/j.ijrobp.2021.07.1406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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29
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[Development of a fluorescent recombinase-aided isothermal amplification-based nucleic acid assay for detection of Leishmania]. ZHONGGUO XUE XI CHONG BING FANG ZHI ZA ZHI = CHINESE JOURNAL OF SCHISTOSOMIASIS CONTROL 2021; 33:452-456. [PMID: 34791841 DOI: 10.16250/j.32.1374.2021187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
OBJECTIVE To develop a fluorescent recombinase-aided isothermal amplification (RAA)-based nucleic acid assay for detection of Leshimania. METHODS Specific primers and probes were designed targeting Leishmania internal transcribed spacer 1 (ITS1) gene for RAA assay, and a fluorescent RAA assay was developed for detection of Leishmania following screening of primer pairs and optimization of primer and probe concentrations. The sensitivity of RAA assay for detection of Leishmania was evaluated using recombinant plasmid containing Leishmania ITS1 gene sequences at different copies and Leshimania genomic DNA at different concentrations as templates, and the specificity of RAA assay for detection of Leishmania was evaluated using the genomic DNA of transfusion-transmitted parasites, including Babesia microti, Toxoplasma gondii, Plamodium vivax, P. ovale, P. falciparum, P. malariae, L. donovani and L. infantum. RESULTS After the optimal primer pair was screened from 9 pairs of primer combinations, the final primer and probe concentrations were optimized as 0.3 μmol/L and 0.08 μmol/L, respectively. Nucleic acid detection of Leishmania was completed by the fluorescent RAA assay at an isothermal temperature of 39 °C within 20 min. Remarkable florescent signals were seen within 5 min following RAA detection of genomic DNA of L. donovani and L. infantum, and no cross-reactions were observed with B. microti, T. gondii, P. vivax, P. ovale, P. falciparum or P. malariae. The lowest limitation of detection of the fluorescent RAA assay was 10 copies/μL recombinant plasmid containing Leishmania ITS1 gene sequences and 1 fg/μL Leishmania genomic DNA. CONCLUSIONS A rapid, simple, sensitive and specific fluorescent RAA assay is successfully developed for detection of L. donovani and L. infantum, which is effective for field screening of leishmaniasis.
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A dynamic range extension system for LHAASO WCDA-1. RADIATION DETECTION TECHNOLOGY AND METHODS 2021. [DOI: 10.1007/s41605-021-00275-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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31
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OC-0306 Performance evaluation of BgRT delivery directed at multiple PET-avid targets. Radiother Oncol 2021. [DOI: 10.1016/s0167-8140(21)06853-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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32
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Peta-electron volt gamma-ray emission from the Crab Nebula. Science 2021; 373:425-430. [PMID: 34261813 DOI: 10.1126/science.abg5137] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 06/23/2021] [Indexed: 11/03/2022]
Abstract
The Crab Nebula is a bright source of gamma rays powered by the Crab Pulsar's rotational energy through the formation and termination of a relativistic electron-positron wind. We report the detection of gamma rays from this source with energies from 5 × 10-4 to 1.1 peta-electron volts with a spectrum showing gradual steepening over three energy decades. The ultrahigh-energy photons imply the presence of a peta-electron volt electron accelerator (a pevatron) in the nebula, with an acceleration rate exceeding 15% of the theoretical limit. We constrain the pevatron's size between 0.025 and 0.1 parsecs and the magnetic field to ≈110 microgauss. The production rate of peta-electron volt electrons, 2.5 × 1036 ergs per second, constitutes 0.5% of the pulsar spin-down luminosity, although we cannot exclude a contribution of peta-electron volt protons to the production of the highest-energy gamma rays.
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[Role of gut-liver-immune axis in the pathogenesis of nonalcoholic steatohepatitis]. ZHONGHUA GAN ZANG BING ZA ZHI = ZHONGHUA GANZANGBING ZAZHI = CHINESE JOURNAL OF HEPATOLOGY 2021; 29:505-509. [PMID: 34225424 DOI: 10.3760/cma.j.cn501113-20210430-00215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease in the world. Liver cirrhosis, liver cancer and a variety of extrahepatic chronic diseases are important risk factors for NAFLD. Currently, there is still a lack of effective therapeutic drugs. Liver inflammation is a key driving factor for the progression of NAFLD, so regulating liver inflammation may provide a potential means to delay and reverse the progression of nonalcoholic steatohepatitis (NASH). Studies have found that the gut-liver-immune axis plays an important role in the progression of NASH. Gut microbiota can use its metabolites to induce glycolipid toxicity, oxidative stress and intestinal barrier damage, while bacterial components such as lipopolysaccharides, peptidoglycans, bacterial DNA and extracellular vesicles can translocate into the liver through the damaged intestinal barrier, causing excessive activation of immune cells, thus aggravating liver inflammation and promoting the progress of NASH. This paper focuses on the gut-liver-immune axis to analyze the gut microbiota mediated liver immunity and its mechanism in the occurrence and development of NASH, so as to lay a theoretical foundation for the research and development of new therapeutic strategies for NASH.
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Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run. PHYSICAL REVIEW LETTERS 2021; 126:241102. [PMID: 34213926 DOI: 10.1103/physrevd.97.102002] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 03/31/2021] [Accepted: 05/23/2021] [Indexed: 05/21/2023]
Abstract
We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.
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Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run. PHYSICAL REVIEW LETTERS 2021; 126:241102. [PMID: 34213926 DOI: 10.1103/physrevlett.126.241102] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 03/31/2021] [Accepted: 05/23/2021] [Indexed: 06/13/2023]
Abstract
We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.
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Extended Very-High-Energy Gamma-Ray Emission Surrounding PSR J0622+3749 Observed by LHAASO-KM2A. PHYSICAL REVIEW LETTERS 2021; 126:241103. [PMID: 34213924 DOI: 10.1103/physrevlett.126.241103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/23/2021] [Accepted: 05/10/2021] [Indexed: 06/13/2023]
Abstract
We report the discovery of an extended very-high-energy (VHE) gamma-ray source around the location of the middle-aged (207.8 kyr) pulsar PSR J0622+3749 with the Large High-Altitude Air Shower Observatory (LHAASO). The source is detected with a significance of 8.2σ for E>25 TeV assuming a Gaussian template. The best-fit location is (right ascension, declination) =(95.47°±0.11°,37.92°±0.09°), and the extension is 0.40°±0.07°. The energy spectrum can be described by a power-law spectrum with an index of -2.92±0.17_{stat}±0.02_{sys}. No clear extended multiwavelength counterpart of the LHAASO source has been found from the radio to sub-TeV bands. The LHAASO observations are consistent with the scenario that VHE electrons escaped from the pulsar, diffused in the interstellar medium, and scattered the interstellar radiation field. If interpreted as the pulsar halo scenario, the diffusion coefficient, inferred for electrons with median energies of ∼160 TeV, is consistent with those obtained from the extended halos around Geminga and Monogem and much smaller than that derived from cosmic ray secondaries. The LHAASO discovery of this source thus likely enriches the class of so-called pulsar halos and confirms that high-energy particles generally diffuse very slowly in the disturbed medium around pulsars.
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Ultrahigh-energy photons up to 1.4 petaelectronvolts from 12 γ-ray Galactic sources. Nature 2021; 594:33-36. [PMID: 34002091 DOI: 10.1038/s41586-021-03498-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 03/26/2021] [Indexed: 02/04/2023]
Abstract
The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 1015 electronvolts) indicates the existence of the so-called PeVatrons-cosmic-ray factories that accelerate particles to PeV energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays1. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref. 2). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane3-6, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators.
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Increasing coenzyme Q 10 yield from Rhodopseudomonas palustris by expressing rate-limiting enzymes and blocking carotenoid and hopanoid pathways. Lett Appl Microbiol 2021; 73:88-95. [PMID: 33783839 DOI: 10.1111/lam.13479] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 03/24/2021] [Accepted: 03/25/2021] [Indexed: 11/29/2022]
Abstract
Coenzyme Q10 (CoQ10 ), a strong antioxidant, is used extensively in food, cosmetic and medicine industries. A natural producer, Rhodopseudomonas palustris, was engineered to overproduce CoQ10 . For increasing the CoQ10 content, crtB gene was deleted to block the carotenoid pathway. crtB gene deletion led to 33% improvement of CoQ10 content over the wild type strain. However, it was found that the yield of hopanoids was also increased by competing for the precursors from carotenoid pathway with CoQ10 pathway. To further increase the CoQ10 content, hopanoid pathway was blocked by deleting shc gene, resulting in R. palustris [Δshc, ΔcrtB] to produce 4·7 mg g-1 DCW CoQ10 , which was 1·2 times higher than the CoQ10 content in the wild type strain. The common strategy of co-expression of rate-limiting enzymes (DXS, DPS and UbiA) was combined with the pathway blocking method resulted in 8·2 mg g-1 DCW of CoQ10 , which was 2·9 times higher than that of wild type strain. The results suggested a synergistic effect among different metabolic engineering strategies. This study demonstrates the potential of R. palustris for CoQ10 production and provides viable strategies to increase CoQ10 titer.
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P89.09 The Landscape of Kinase Domain Duplication (KDD) in Chinese Lung Cancer Patients. J Thorac Oncol 2021. [DOI: 10.1016/j.jtho.2021.01.1274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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MA08.11 Identification of Clinical Features to Predict the Consistency of Mutational Profiles Obtained From Plasma and Tissue of Advanced NSCLC Patient. J Thorac Oncol 2021. [DOI: 10.1016/j.jtho.2021.01.197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Feasibility of the application of mixed reality in mandible reconstruction with fibula flap: A cadaveric specimen study. JOURNAL OF STOMATOLOGY, ORAL AND MAXILLOFACIAL SURGERY 2021; 122:e45-e49. [PMID: 33434746 DOI: 10.1016/j.jormas.2021.01.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 12/02/2020] [Accepted: 01/04/2021] [Indexed: 11/16/2022]
Abstract
BACKGROUND In recent years, a new technology, mixed reality (MR), has emerged and surpassed the limitations of augmented reality (AR) with its inability to interact with hologram. This study aimed to investigate the feasibility of the application of MR in mandible reconstruction with fibula flap. METHODS Computed tomography (CT) examination was performed for one cadaveric mandible and ten fibula bones. Using professional software Proplan CMF 3.0 (Materialize, Leuven, Belgium), we created a defected mandibular model and simulated the reconstruction design with these 10 fibula bones. The surgical plans were transferred to the HoloLens. We used HoloLens to guide the osteotomy and shaping of the fibular bone. After fixing the fibular segments using the Ti template, all segments underwent a CT examination. Before and after objects were compared for measurements of the location of fibular osteotomies, angular deviation of fibular segments, and intergonial angle distances. RESULTS The mean location of the fibular osteotomies, angular deviation of the fibular segments, and intergonial angle distances were 2.11 ± 1.31 mm, 2.85°± 1.97°, and 7.24 ± 3.42 mm, respectively. CONCLUSION The experimental results revealed that slight deviations remained in the accuracy of fibular osteotomy. With the further development of technology, it has the potential to improve the efficiency and precision of the reconstructive surgery.
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No pulsed radio emission during a bursting phase of a Galactic magnetar. Nature 2020; 587:63-65. [PMID: 33149293 DOI: 10.1038/s41586-020-2839-y] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 08/31/2020] [Indexed: 11/10/2022]
Abstract
Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances1-3. It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources4-13, but no convincing evidence has been collected so far14. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft γ-ray bursts15. One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft γ-ray/hard-X-ray flare18-21. Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-γ-ray repeater (SGR) bursts were detected in γ-ray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB-SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst.
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Three-field versus two-field lymphadenectomy in transthoracic oesophagectomy for oesophageal squamous cell carcinoma: short-term outcomes of a randomized clinical trial. Br J Surg 2020; 107:647-654. [PMID: 32108326 DOI: 10.1002/bjs.11497] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 10/10/2019] [Accepted: 12/10/2019] [Indexed: 11/10/2022]
Abstract
BACKGROUND The benefit and harm of three-field lymphadenectomy for oesophageal cancer are still unknown. The aim of this study was to compare overall survival and morbidity and mortality between three- and two-field lymphadenectomy in patients with oesophageal squamous cell carcinoma. METHODS Between March 2013 and November 2016, patients with squamous cell carcinoma of the middle or distal oesophagus were assigned randomly to open oesophagectomy with three-field (cervical-thoracic-abdominal) or two-field (thoracic-abdominal) lymphadenectomy. No chemo(radio) therapy was given before surgery. This paper reports on the secondary outcomes of the study: pathology and surgical complications. RESULTS Some 400 patients were randomized, 200 in each group. A median of 37 (i.q.r. 30-49) lymph nodes were dissected in the three-field group, compared with 24 (18-30) in the two-field group (P < 0·001). Some 43 of 200 patients (21·5 per cent) in the three-field group had cervical lymph node metastasis. More patients in the three-field group had pN3 disease: 21 of 200 (10·5 per cent) versus 10 of 200 (5·0 per cent) (P = 0·040). The rate and severity of postoperative complications were comparable between the two groups, except that six patients in the three-field arm needed reintubation compared with none in the two-field group (3·0 versus 0 per cent; P = 0·030). The 90-day mortality rate was 0 per cent in the three-field group and 0·5 per cent (1 patient) in the two-field group (P = 1·000). CONCLUSION Oesophagectomy with three-field lymphadenectomy increased the number of lymph nodes dissected and led to stage migration owing to a 21·5 per cent rate of cervical lymph node metastasis. Postoperative complications were largely comparable between two- and three-field lymphadenectomy. Registration number: NCT01807936 ( https://www.clinicaltrials.gov).
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Prospects for observing and localizing gravitational-wave transients with Advanced LIGO, Advanced Virgo and KAGRA. LIVING REVIEWS IN RELATIVITY 2020; 23:3. [PMID: 33015351 PMCID: PMC7520625 DOI: 10.1007/s41114-020-00026-9] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 05/27/2020] [Indexed: 05/05/2023]
Abstract
We present our current best estimate of the plausible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors over the next several years, with the intention of providing information to facilitate planning for multi-messenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitational-wave signals for the third (O3), fourth (O4) and fifth observing (O5) runs, including the planned upgrades of the Advanced LIGO and Advanced Virgo detectors. We study the capability of the network to determine the sky location of the source for gravitational-wave signals from the inspiral of binary systems of compact objects, that is binary neutron star, neutron star-black hole, and binary black hole systems. The ability to localize the sources is given as a sky-area probability, luminosity distance, and comoving volume. The median sky localization area (90% credible region) is expected to be a few hundreds of square degrees for all types of binary systems during O3 with the Advanced LIGO and Virgo (HLV) network. The median sky localization area will improve to a few tens of square degrees during O4 with the Advanced LIGO, Virgo, and KAGRA (HLVK) network. During O3, the median localization volume (90% credible region) is expected to be on the order of 10 5 , 10 6 , 10 7 Mpc 3 for binary neutron star, neutron star-black hole, and binary black hole systems, respectively. The localization volume in O4 is expected to be about a factor two smaller than in O3. We predict a detection count of 1 - 1 + 12 ( 10 - 10 + 52 ) for binary neutron star mergers, of 0 - 0 + 19 ( 1 - 1 + 91 ) for neutron star-black hole mergers, and 17 - 11 + 22 ( 79 - 44 + 89 ) for binary black hole mergers in a one-calendar-year observing run of the HLV network during O3 (HLVK network during O4). We evaluate sensitivity and localization expectations for unmodeled signal searches, including the search for intermediate mass black hole binary mergers.
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MiR-124a inhibits proliferation and invasion of rheumatoid arthritis synovial fibroblasts. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2019; 22:4581-4588. [PMID: 30058700 DOI: 10.26355/eurrev_201807_15515] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE To investigate the impact of miR-124Aa on the proliferation, invasion and cytokine excretion of rheumatoid arthritis synovial fibroblasts (RASFs) in patients with rheumatoid arthritis (RA). PATIENTS AND METHODS RASFs were separated for in-vitro culture, and transfected using lipidosome that connected with chemically synthesized miR-124a mimic or miR-124a inhibitor. Then, MTT, transwell chamber, and flow-cytometry were used to detect the impact on the proliferation, invasion, and apoptosis of RASFs; RT-PCR and Western-blotting were employed to measure the effect of miR-124a on the expressions of matrixmetalloproteinase3/13 (MMP3/13) and interleukin1β (IL-1β) of RASFs. RESULTS miR-124a significantly suppresses the proliferation of RASFs, while inhibits the invasion of RASFs. The flow cytometry indicated that miR-124a showed no significant effect on the apoptosis of RASFs. Finally, miR-124a downregulates the expressions of MMP3/13 and IL-1β. CONCLUSIONS MiR-124a is of great significance for the onset of RA by inhibiting the proliferation and invasion of RASFs possibly through downregulating the expression of MMP3/13 and IL-1β.
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Carbon monoxide releasing molecule-2 suppresses proliferation, migration, invasion, and promotes apoptosis in non-small cell lung cancer Calu-3 cells. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2019; 22:1948-1957. [PMID: 29687848 DOI: 10.26355/eurrev_201804_14720] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Non-small cell lung cancer (NSCLC) is the most common type of lung cancer, which is the leading cause of cancer-related morbidity and mortality worldwide. The carbon monoxide-releasing molecules (CO-RMs) are transition metal carbonyls with the capacity to release carbon monoxide (CO). The aims of our study were to assess the effects and underlying mechanisms of CO-releasing molecules-2 (CORM-2) on proliferation, migration, invasion and apoptosis in NSCLC cells, and to evaluate its potential application for lung cancer. MATERIALS AND METHODS NSCLC cells Calu-3 were treated with CORM-2, negative control and blank control. Cell proliferation, migration and invasion were assessed by cell Counting Kit-8 (CCK-8), scratch assay and matrigel invasion chamber experiment, respectively. Apoptosis was measured by flow cytometry. Real-time PCR and Western blot were applied to examine the expression of apoptosis-related molecules on mRNA and protein levels. RESULTS CORM-2 markedly attenuated proliferation, migration and invasion of Calu-3 cells. CORM-2 treatment also significantly reduced the ratio of B cell lymphoma 2 (Bcl-2)/B cell lymphoma 2 associated X protein (Bax) while increased expression of caspase-3 and cytochrome c. The optimal dose of CORM-2 for Calu-3 cells was 100 µM. CONCLUSIONS CORM-2 modulates biological functions of NSCLC cells and may provide a novel therapeutic strategy for lung cancer.
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P1.14-17 Genomic Evolution During TKI Treatment in Non-Small Cell Lung Cancer Patients With or Without Acquired T790M Mutation. J Thorac Oncol 2019. [DOI: 10.1016/j.jtho.2019.08.1168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Evaluation of structural changes and intracellular substance leakage of
Escherichia coli
O157:H7 induced by ohmic heating. J Appl Microbiol 2019; 127:1430-1441. [DOI: 10.1111/jam.14411] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 07/27/2019] [Accepted: 08/07/2019] [Indexed: 12/15/2022]
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Impact of pre-existing disorder on radiation defect dynamics in Si. Sci Rep 2019; 9:12377. [PMID: 31451746 PMCID: PMC6710428 DOI: 10.1038/s41598-019-48415-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 07/29/2019] [Indexed: 11/26/2022] Open
Abstract
The effect of pre-existing lattice defects on radiation defect dynamics in solids remains unexplored. Here, we use a pulsed beam method to measure the time constant of defect relaxation for 500 keV Ar ion bombardment of Si at 100 °C with the following two representative types of pre- existing lattice disorder: (i) point defect clusters and (ii) so-called “clamshell” defects consisting of a high density of dislocations. Results show that point defect clusters slow down defect relaxation processes, while regions with dislocations exhibit faster defect interaction dynamics. These experimental observations demonstrate that the dynamic aspects of damage buildup, attributed to defect trapping-detrapping processes, can be controlled by defect engineering.
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All-sky search for continuous gravitational waves from isolated neutron stars using Advanced LIGO O2 data. Int J Clin Exp Med 2019. [DOI: 10.1103/physrevd.100.024004] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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