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In this Letter we try to search for signals generated by ultraheavy dark matter at the Large High Altitude Air Shower Observatory (LHAASO) data. We look for possible γ rays by dark matter annihilation or decay from 16 dwarf spheroidal galaxies in the field of view of the LHAASO. Dwarf spheroidal galaxies are among the most promising targets for indirect detection of dark matter that have low fluxes of astrophysical γ-ray background while having large amount of dark matter. By analyzing more than 700 days of observational data at LHAASO, no significant dark matter signal from 1 TeV to 1 EeV is detected. Accordingly we derive the most stringent constraints on the ultraheavy dark matter annihilation cross section up to EeV. The constraints on the lifetime of dark matter in decay mode are also derived.
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Objective: To investigate pertinent risk factors for postoperative pancreatic fistula(POPF) after robotic-assisted distal pancreatectomy(RDP). Methods: This is a retrospective cohort study. Clinical data of 1 211 patients who underwent various methods of distal pancreatectomy at the Department of General Surgery,Ruijin Hospital,Shanghai Jiaotong University School of Medicine,between January 2021 and December 2023 were retrospectively collected. Among the 1 211 patients,440 cases were in the robot-assisted group(173 males and 267 females),with an age(M(IQR)) of 55(29)years;720 cases were in the open surgery group (390 males and 330 females),with an age of 64(15)years;and 51 cases were in the laparoscopic group(17 males and 34 females),with an age of 56(25)years. These 440 patients who underwent RDP were divided into two cohorts based on the presence of clinically relevant pancreatic fistulas(grades B and C). Univariate and multivariate analysis were performed on 27 factors related to POPF. Univariate analysis methods included independent sample t-test,Mann-Whitney U test,and χ2 test,while multivariate analysis utilized binary logistic regression. Results: After stratification by pathological type,there was no significant difference in the incidence of pancreatic fistula between the robot-assisted group and the open surgery group(benign tumor:χ2=1.200,P=0.952;malignant tumor:χ2=0.391,P=0.532). The surgical duration of the RDP group (Z1=15.113,P1<0.01; Z2=4.232, P2<0.01) was significantly shorter than that of the open surgery and laparoscopic groups,so as the intraoperative blood loss (Z1=12.530,P1<0.01;Z2=2.550,P2=0.032). Postoperative hospital stay in the RDP group was significantly shorter than that in the open surgery group (Z1=10.947, P1<0.01), but not different from that in the laparoscopic group (P2>0.05). All 440 patients underwent successful surgery,of which there was only 1 case who underwent a conversion to open surgery. A total of 104 patients(23.6%) developed clinically relevant pancreatic fistulas,and no perioperative mortality was observed. Univariate analysis revealed that 6 factors were associated with POPF after RDP: gender(χ2=12.048,P=0.001),history of smoking (χ2=6.327,P=0.012),history of alcohol consumption (χ2=17.597,P<0.01),manual pancreas division (χ2=9.839,P=0.002),early elevation of amylase in drainage fluid (Z=5.187,P<0.01),and delayed gastric emptying (χ2=4.485,P=0.034). No statistically significant association with POPF was found for the remaining factors(all P>0.05).The cut-off value for the early amylase level in the drainage fluid was determined to be 7 719.5 IU/ml,with an area under curve of 0.676 determined by receiver operating characteristic curve analysis. Binary logistic regression analysis identified a history of alcohol consumption(P=0.002,95%CI: 0.112 to 0.623), manual pancreas division(P=0.001,95%CI:1.446 to 4.082),early amylase level of drainage fluid ≥7 719.5 IU/ml(P<0.01,95%CI:0.151 to 0.438),and delayed gastric emptying (P=0.020, 95%CI: 1.131 to 4.233) as independent risk factors for POPF of RDP. Conclusion: Patients with pancreatic body and tail tumors who receive RDP therapy are at increased risk of developing a pancreatic fistula if they have a history of alcohol consumption,manual pancreas division,early elevation of amylase in drainage fluid to ≥7 719.5 IU/ml, or delayed gastric emptying.
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Pancreatectomia , Fístula Pancreática , Neoplasias Pancreáticas , Complicações Pós-Operatórias , Procedimentos Cirúrgicos Robóticos , Humanos , Fístula Pancreática/etiologia , Fístula Pancreática/epidemiologia , Masculino , Feminino , Estudos Retrospectivos , Pancreatectomia/métodos , Pancreatectomia/efeitos adversos , Fatores de Risco , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Robóticos/métodos , Neoplasias Pancreáticas/cirurgia , Laparoscopia/métodos , Idoso , AdultoRESUMO
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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Malignant tumors in children are one of the most important diseases that threaten the health and quality of life of children and are the second most common cause of death in children.With the continuous improvement and progress of treatment technology, the long-term survival rate of children with tumor has been significantly improved, but both the disease itself and the treatment can impair the immune function of children, which makes them vulnerable to various infectious diseases and secondary serious complications, and even become a source of infection, endangering the health of others. Vaccination is the most cost-effective measure to prevent infectious diseases. For children with normal immune functions, the benefits of vaccination usually outweigh the disadvantages. However, there is a lack of detailed data on the vaccination situation, efficacy and safety of vaccine use for such immunocompromised tumor survivors, and there are no authoritative and uniform vaccination recommendations. This article reviewed and summarized the literature and consensus of some domestic and foreign scholars on current status of post-treatment vaccination status, efficacy and safety of vaccination for children with tumors after treatment, with the aim of providing a reference for the practice in this field in China.
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Doenças Transmissíveis , Neoplasias , Vacinas , Criança , Humanos , Qualidade de Vida , Vacinação , Neoplasias/prevenção & controleRESUMO
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°
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Objective: To explore the correlation between pulmonary quantitative CT measurement indicators and respiratory symptoms in patients with stable chronic obstructive pulmonary disease (COPD). Methods: A total of 186 patients with COPD in stable stage who visited in the outpatient department of Beijing Hospital from March 2021 to February 2022 were prospectively included. Demographic data, respiratory symptoms and lung function were collected. The original DICOM data of high-resolution CT (HRCT) were processed using the FACT medical imaging information system and the pulmonary emphysema index pixel index-950 (PI-950) and the airway wall thickness (4-6 T) and the percentage of airway area (4-6 WA%) of the 4-6 generation bronchi which represent the segmental and subsegmental bronchi were measured automatically. According to the modified British medical research council dyspnea scale (mMRC, 0-1 point for low score group, 2-4 points for high score group), chronic obstructive pulmonary disease assessment test (CAT, score<10 points for low score group,≥10 points for high score group), cough, expectoration and wheezing (asymptomatic group and symptomatic group), they were divided into two groups as dependent variables. The relationship between imaging parameters and the above symptoms was evaluated using a logistic regression model. Results: The study ultimately included 186 patients who met the inclusion criteria, including 162 males and 24 females, aged (68.9±9.3) years old. There were 83 patients in the high mMRC group, 120 patients in the high CAT group, 146 patients in the cough group, 154 patients in the expectoration group, and 65 patients in the wheezing group. The age and emphysema parameter PI-950 in the high score group of mMRC were higher than those in the low score group, while the percentage of the forced expiratory volume in 1 second (FEV1) predicted value (FEV1 pred) after medication, the percentage of carbon monoxide diffusion volume (DLCO) predicted value (DLCO pred), and the percentage of the maximum midexpiratory flow (MMEF) predicted value (MMEF pred) after medication were lower than those in the low score group (all P<0.05). The age of the high CAT group was higher than that of the low score group, while FEV1 pred and MMEF pred after medication were lower than those of the low score group (all P<0.05). The proportion of males, patients with smoking history, and smoking index in the cough group were higher than those in the non cough group, while the 4 WA% was lower than that in the non cough group (all P<0.05). The proportion of males, patients with smoking history, smoking index, and PI-950 in the expectoration group were higher than those in the non expectoration group, while FEV1 pred after medication and 4 WA% were lower than those in the non expectoration group (all P<0.05). The 5 WA% and 6 WA% of the wheezing group were higher than those of the non wheezing group, while MMEF pred after medication was lower than that of the non wheezing group (all P<0.05). Multivariate logistic regression analysis showed that after adjusting for demographic characteristics, smoking, combined diseases, lung function and other confounding factors, for every 10% increase in PI-950, the likelihood of developing more severe dyspnea for the patients (high score group according to mMRC) increased by 67.3% (OR=1.673, 95%CI: 1.052-2.658); Every 10% increase in 6WA% increased the likelihood of wheezing by 3.189 times (OR=4.189, 95%CI: 1.070-16.395). No correlation was found between various imaging indicators and cough, expectoration, and CAT scores (P>0.05). Conclusion: Quantitative CT measurement indicators in stable COPD patients can explain the presence and severity of respiratory symptoms, the pulmonary emphysema indicator is associated with dyspnea, and the percentage of proximal airway wall area is associated with wheezing.
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Doença Pulmonar Obstrutiva Crônica , Enfisema Pulmonar , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Tosse , Sons Respiratórios , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Pulmão , Volume Expiratório Forçado , Dispneia , Tomografia Computadorizada por Raios XRESUMO
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 (LHAASO) of the bright GRB 221009A, which serendipitously occurred within the instrument's 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 and then rose to a peak ~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 of ~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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CT screening has markedly reduced the lung cancer mortality in high-risk population and increased the detection of early-stage pulmonary neoplasms, including multiple pulmonary nodules, especially those with a ground-glass appearance on CT. Multiple primary lung cancer (MPLC) constitutes a specific subtype of lung cancer with indolent biological behaviors, which is predominantly early-stage adenocarcinoma. Although MPLC progresses slowly with rare lymphatic metastasis, existence of synchronous lesions and distributed location of these nodules still pose difficulty for the management of such patients. One single operation is usually insufficient to eradicate all neoplastic lesions, whereas repeated surgical procedures bring about another dilemma: whether clinical benefits of surgical treatment outweigh loss of pulmonary function following multiple operations. Therefore, despite the anxiety for treatment among MPLC patients, whether and how to treat the patient should be assessed meticulously. Currently there is a heated discussion upon the timing of clinical intervention, operation mode and the application of local therapy in MPLC. Based on clinical experience of our multiple disciplinary team, we have summarized and commented on the evaluation, surgical treatment, non-surgical local treatment, targeted therapy and immunotherapy of MPLC in this article to provide further insight into this field.
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Adenocarcinoma , Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Humanos , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/cirurgia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/cirurgia , Pulmão/patologia , Tomografia Computadorizada por Raios XRESUMO
Epidermal growth factor receptor (EGFR) mutation status differs according to ethnicity, gender, smoking history, and histology types. The present study aimed to evaluate EGFR mutation status in patients with non-small cell lung cancer (NSCLC) and further explore its association with clinical characteristics and prognosis in advanced NSCLC patients (Stage IIIB-IV). 238 NSCLC patients were enrolled in this study from October 2016 through December 2019. Patient characteristics and clinical data including age, gender, smoking history, histology types, tumor stage, survival status, and time were collected via electronic medical record system or telephone. 21 somatic mutations which spanned exons 18-21 of EGFR were detected using the amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) method, followed by analysis of links to clinical characteristics, progression-free survival (PFS) and overall survival (OS). 103 patients were detected harboring EGFR mutations among the 238 cases tested (43.3%), and exons 19 and 21 were the highest mutation frequencies, with 20.6% and 19.3% respectively. The EGFR mutation rate was much higher in female versus male (57.4% vs 31.5%, p <0.001), in non-smokers compared to smokers (56.8% vs 25.9%, p <0.001), and in those with adenocarcinoma than other histology types (48.3% vs 3.7%, p <0.001). For patients in advanced stage, median PFS was 11 months in patients harboring EGFR mutations, versus 4 months in patients with wild type EGFR (p <0.001); median OS was 24 versus 12 months (p <0.001). Never smoking (p = 0.042) and adenocarcinoma (p = 0.007) were independent favorable factors for EGFR mutations. Our data strengthen the findings of high prevalence of EGFR mutations in Asian patients with NSCLC. Mutations are prevalent in those patients who are female, adenocarcinoma, and have never smoked. Moreover, advanced EGFR mutation-positive patients have better PFS and OS than those with wild type EGFR.
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Objective: To study the risk factors of adverse pregnancy outcomes for the diagnosis and treatment of pregnancy after cesarean section complicated with placenta previa. Methods: A national multicenter retrospective study was conducted to select a total of 747 pregnant women with the third trimester singleton pregnancy after cesarean section complicated with placenta previa from 12 tertiary hospitals in January 1st to December 31st, 2018. The risk factors of severe adverse outcomes [hysterectomy, intraoperative blood loss ≥1 000 ml, intraoperative diagnosis of placenta accreta spectrum disorders (PAS)] in pregnant women with second pregnancy complicated with placenta previa after cesarean section were investigated by logistic regression analysis. The roles of prenatal ultrasonography and magnetic resonance imaging (MRI) in the prediction of PAS and severe adverse outcomes were observed. According to whether vascular intervention was performed (uterine artery embolization or abdominal aortic balloon occlusion), the pregnant women were divided into the blocked group and the unblocked group, and the maternal and infant perinatal outcomes between the two groups were compared. Results: (1) General information: the hysterectomy rate of 747 pregnant women with second pregnancy complicated with placenta previa after cesarean section was 10.4% (78/747), the intraoperative blood loss ≥1 000 ml in 55.8% (417/747), and PAS was confirmed in 47.5% (355/747). The incidence of uterine rupture was 0.8% (6/747). (2) Analysis of risk factors for severe adverse outcomes: based on binary unconditioned logistic regression univariate and multivariate analysis, the risk factors for hysterectomy were the mode of vascular embolization and intraoperative blood loss. The probability of hysterectomy with uterine artery embolization was 5.319 times higher than that with abdominal aortic balloon occlusion (95%CI: 1.346-21.018). The risk factors of intraoperative blood loss ≥1 000 ml were the number of cesarean section delivery, ultrasonography indicated PAS and suspected PAS, intraoperative PAS and complete placenta previa. The risk factors for intraoperative PAS were uterine scar thickness, ultrasonography indicated PAS and suspected PAS, MRI indicated PAS and suspected PAS, and complete placenta previa. (3) The roles of ultrasonography and MRI in predicting PAS: the sensitivity and specificity of ultrasonography in predicting PAS were 47.5% and 88.4%; the kappa value was 0.279 (P<0.001), with fair agreement. The sensitivity and specificity of MRI to predict PAS were 79.2% and 97.8%, respectively. The kappa value was 0.702 (P<0.001), indicating a good agreement. The intraoperative blood loss and hysterectomy rate of pregnant women with PAS indicated by ultrasonography and MRI were significantly higher than those with PAS only by ultrasonography or MRI. (4) Influence of vascular occlusion on pregnancy outcome: there were no significant differences in intraoperative blood loss and incidence of intraoperative bleeding ≥1 000 ml between the blocked group and the unblocked group (all P>0.05). There was no significant difference in intraoperative blood loss between the pregnant women with abdominal aortic balloon occlusion, uterine artery embolization and those without occlusion (P=0.409). The hysterectomy rate of pregnant women with uterine artery embolization was significantly higher than those with abdominal aortic balloon occlusion [39.3% (22/56) vs 10.0% (5/50), P=0.001]. Conclusions: In the third trimester of pregnancy with placenta previa after cesarean section, MRI examination has better consistency in predicting PAS than ultrasonography examination. Ultrasonography examination combined with MRI examination could effectively predict the hysterectomy rate and intraoperative blood loss. Vascular occlusion could not reduce the amount of intraoperative blood loss. The hysterectomy rate of pregnant women with uterine artery embolization is higher than those with abdominal aortic balloon occlusion.
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Placenta Acreta , Placenta Prévia , Gravidez , Lactente , Feminino , Humanos , Cesárea , Placenta Acreta/cirurgia , Placenta Prévia/cirurgia , Estudos Retrospectivos , Perda Sanguínea Cirúrgica , Gestantes , Fatores de RiscoRESUMO
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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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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Objective: To study the risk factors of adverse pregnancy outcomes for induced abortion of cesarean scar pregnancy in midtrimester. Methods: A national multicenter retrospective study was conducted. A total of 154 singletons pregnant women with cesarean scar pregnancy during the second trimester induced abortion by various reasons in 12 tertiary A hospitals were selected, their pregnant outcomes were observed and the risk factors of serious adverse outcomes were analyzed with univariate and multivariate logstic regression; the role of ultrasound and MRI in predicting placenta accreta and severe adverse outcomes was evaluated, the effectiveness of uterine artery embolization (UAE) in preventing hemorrhage in pregnant women with and without placenta accreta was compared. Results: Among 154 subjects, the rate of placenta accreta was 42.2% (65/154), the rate of postpartum hemorrhage≥1 000 ml was 39.0% (60/154), the rate of hysterectomy was 14.9% (23/154), the rate of uterine rupture was 0.6% (1/154). The risk factor of postpartum hemorrhage≥1 000 ml and hysterectomy was placenta accreta (P<0.01). For each increase in the number of parity, the risk of placenta accreta increased 2.385 times (95%CI: 1.046-5.439; P=0.039); and the risk of placenta accreta decreased with increasing ultrasound measurement of scar myometrium thickness (OR=0.033, 95%CI: 0.001-0.762; P=0.033). The amount of postpartum hemorrhage and hysterectomy rate in the group with placenta accreta diagnosed by ultrasound combined with MRI were not significantly different from those in the group with placenta accreta diagnosed by ultrasound only or MRI only (all P>0.05). For pregnant women with placenta accreta, there were no significant difference in the amount of bleeding and hysterectomy rate between the UAE group [median: 1 300 ml; 34% (16/47)] and the non-embolization group (all P>0.05); in pregnant women without placenta accreta, the amount of bleeding in the UAE group was lower than that in the non-embolization group (median: 100 vs 600 ml; P<0.01), but there was no significant difference in hysterectomy rate [2% (1/56) vs 9% (3/33); P>0.05]. Conclusions: (1) Placenta accreta is the only risk factor of postpartum hemorrhage≥1 000 ml with hysterectomy for induced abortion of cesarean scar pregnancy in midtrimester; multi-parity and ultrasound measurement of scar myometrium thickness are risk factors for placenta accreta. (2) The technique of using ultrasound and MRI in predicting placenta accreta of cesarean scar pregnancy needs to be improved. (3) It is necessary to discuss of UAE in preventing postpartum hemorrhage for induced abortion of cesarean scar pregnancy in midtrimester.
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Placenta Acreta , Embolização da Artéria Uterina , Cicatriz , Feminino , Humanos , Placenta Acreta/diagnóstico por imagem , Placenta Acreta/epidemiologia , Gravidez , Segundo Trimestre da Gravidez , Estudos RetrospectivosRESUMO
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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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 â¼160 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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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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BACKGROUND: This study evaluated maintenance treatment with niraparib, a potent inhibitor of poly(ADP-ribose) polymerase 1/2, in patients with platinum-sensitive recurrent ovarian cancer. PATIENTS AND METHODS: In this phase III, double-blind, placebo-controlled study conducted at 30 centers in China, adults with platinum-sensitive recurrent ovarian cancer who had responded to their most recent platinum-containing chemotherapy were randomized 2 : 1 to receive oral niraparib (300 mg/day) or matched placebo until disease progression or unacceptable toxicity (NCT03705156). Following a protocol amendment, patients with a bodyweight <77 kg or a platelet count <150 × 103/µl received 200 mg/day, and all other patients 300 mg/day, as an individualized starting dose (ISD). Randomization was carried out by an interactive web response system and stratified by BRCA mutation, time to recurrence following penultimate chemotherapy, and response to most recent chemotherapy. The primary endpoint was progression-free survival (PFS) assessed by blinded independent central review. RESULTS: Between 26 September 2017 and 2 February 2019, 265 patients were randomized to receive niraparib (n = 177) or placebo (n = 88); 249 patients received an ISD (300 mg, n = 14; 200 mg, n = 235) as per protocol. In the intention-to-treat population, median PFS was significantly longer for patients receiving niraparib versus placebo: 18.3 [95% confidence interval (CI), 10.9-not evaluable] versus 5.4 (95% CI, 3.7-5.7) months [hazard ratio (HR) = 0.32; 95% CI, 0.23-0.45; P < 0.0001], and a similar PFS benefit was observed in patients receiving an ISD, regardless of BRCA mutation status. Grade ≥3 treatment-emergent adverse events occurred in 50.8% and 19.3% of patients who received niraparib and placebo, respectively; the most common events were neutrophil count decreased (20.3% versus 8.0%) and anemia (14.7% versus 2.3%). CONCLUSIONS: Niraparib maintenance treatment reduced the risk of disease progression or death by 68% and prolonged PFS compared to placebo in patients with platinum-sensitive recurrent ovarian cancer. Individualized niraparib dosing is effective and safe and should be considered standard practice in this setting.
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Neoplasias Ovarianas , Inibidores de Poli(ADP-Ribose) Polimerases , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica , China , Método Duplo-Cego , Feminino , Humanos , Indazóis , Quimioterapia de Manutenção , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Piperidinas , Inibidores de Poli(ADP-Ribose) Polimerases/efeitos adversosRESUMO
Objective: To analyze the clinical features of cystic fibrosis (CF) associated allergic bronchopulmonary aspergillosis (ABPA) in children. Methods: A retrospective study was performed in 22 children who were diagnosed with CF associated ABPA in Beijing Children's Hospital affiliated to Capital Medical University from March 2010 to March 2020. The clinical features, imaging characteristics, laboratory results and the prognosis were reviewed. Results: A total of 22 cases met the diagnostic criterion, including 12 males and 10 females. The age of diagnosis was (10.4±2.8) years and the age of onset was (5.5±4.4) years. Clinical manifestations included cough and expectoration (22 cases), recurrent wheezing (15 cases), hemoptysis (7 cases), failure to thrive (12 cases), pancreatitis (10 cases), hepatomegaly (7 cases), splenomegaly (4 cases) and steatorrhea (4 cases). CT scans of all the patients showed pulmonary infiltrates and central bronchiectasis, combined with mucoid impaction in 17 cases and high density mucus plug in 12 cases. Eosinophilia was found in 18 patients. Total IgE and serum levels of A. fumigatus-specific IgE were elevated in all 22 patients. Positive culture of sputum or bronchoalvedar lauage fluid for fungus were in 15 cases, with single Aspergillus infection in 8 cases and mixed Aspergillus infection in 3 cases. The predominant bacteria found in the airways were Pseudomonas aeruginosa (17 cases), followed by staphylococcas. aureus (6 cases) and stenotrophomonas. maltophilia (5 cases). Pulmonary function revealed obstructive ventilation dysfunction in 4 cases, mixed dysfunction in 11 cases, and small airway dysfunction in 4 cases. Regarding the treatment, 3 were treated only with systemic corticosteroid, while the remaining 19 cases also received antifungal agents.The follow up continued for 1-7 years, and 6 maintained remission, 10 had recurrent episodes, 1 died, and 5 lost to follow up. Conclusions: CF associated ABPA is extremely rare in China. The overlapping clinical, radiographic, and immunologic features of these two diseases make the diagnosis challenging. Systemic corticosteroids are considered the first-line therapy for these patients, and adjuvant antifungal agents may be helpful. Recurrence rate in our center is high.
Assuntos
Aspergilose Broncopulmonar Alérgica/complicações , Aspergillus fumigatus/isolamento & purificação , Fibrose Cística/complicações , Escarro/microbiologia , Aspergilose Broncopulmonar Alérgica/tratamento farmacológico , Criança , China , Fibrose Cística/diagnóstico , Fibrose Cística/microbiologia , Feminino , Glucocorticoides/uso terapêutico , Humanos , Masculino , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Objective: To evaluate the clinical effects of anterolateral thigh free flap with fascia lata in the repair of dura mater defect after resection of head squamous cell carcinoma. Methods: From June 2016 to June 2018, Xijing Hospital of Air Force Medical University applied the free transplantation of anterolateral thigh flap with fascia lata to repair the dura mater defect of 12 patients with head squamous cell carcinoma, including 9 males and 3 females, aged from 35 to 74 years. The size of scalp soft tissue defects in patients after carcinoma resection ranged from 12 cm×10 cm to 24 cm×21 cm, and the size of dura mater defect of patients ranged from 7 cm×6 cm to 16 cm×14 cm. The size of flap of patients ranged from 14 cm×12 cm to 27 cm×24 cm, and the size of fascia lata ranged from 8 cm×7 cm to 17 cm×15 cm. The superficial temporal artery and middle temporal vein were connected by end to end anastomosis with the first musculocutaneous perforating branch of the descending branch of lateral femoral artery and its accompanying vein. The flap donor area was transplanted with autologous split-thickness skin graft from trunk and fixed with packing. Postoperative survival of flaps and skin grafts was observed. The patients were followed up regularly. The cranial magnetic resonance imaging was performed to observe the recurrence of intracranial tumors and dural integrity, shape of the flap and whether the donor site region was left with significant dysfunction were observed. Results: All the flaps and skin grafts survived well in 12 patients after surgery. Ten patients had primary healing at the edge of the flap suture; 2 patients had local sinus tract formation at the suture site of flap, with a small amount of cerebrospinal fluid leakage, and were recovered after outpatient dressing change. The patients were followed up for 10 to 36 months, and 3 patients with tumors involving in the dura mater sagittal sinus region had postoperative intracranial tumor recurrence. The tumor was resected again. All the patients had good dural integrity. The flaps of all patients were in good shape, and no obvious dysfunction remained in the flap donor site. Conclusions: Free transplantation of anterolateral thigh flap with fascia lata is an effective and reliable method to repair the dura mater defect following head squamous cell carcinoma resection. It can repair the scalp and dura mater defects caused by the invasion of squamous cell carcinoma and provide possibilities for skull reconstruction.