Gamma-Ray Observation of the Cygnus Region in the 100-TeV Energy Region

We report observations of gamma-ray emissions with energies in the 100-TeV energy region from the Cygnus region in our Galaxy. Two sources are significantly detected in the directions of the Cygnus OB1 and OB2 associations. Based on their positional coincidences, we associate one with a pulsar PSR J2032+4127 and the other mainly with a pulsar wind nebula PWN G75.2+0.1, with the pulsar moving away from its original birthplace situated around the centroid of the observed gamma-ray emission. This work would stimulate further studies of particle acceleration mechanisms at these gamma-ray sources.

Peta-electron volt gamma-ray emission from the Crab Nebula

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.

Extended Very-High-Energy Gamma-Ray Emission Surrounding PSR J0622+3749 Observed by LHAASO-KM2A

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.

[Reoperation rate and related factors in patients with Crohn's disease]

Objective: To analyze the cumulative reoperation rate of postoperative Crohn's disease (CD) patients and investigate the operation reasons and the effects of drugs on surgical recurrence. Method: Patients with Crohn's disease who had undergone intestinal resection from January 2000 to March 2020 in Peking Union Medical College Hospital were enrolled. Patients were divided into reoperation and non-reoperation group according to whether they had a second operation. And the basic characteristics and the reasons for the primary and second operation were retrospectively analyzed. Meanwhile, patients were divided into low-risk reoperation group and high-risk group based on risk stratification. Kaplan-Meier methods were performed to analyze the cumulative surgical recurrence rate and to compare the recurrence rate in different risk stratification and chi-square tests was used to analyze the effects of different maintenance drugs on reoperation. Result: A total of 160 patients were enrolled in the study. There were 110 males and 50 females, and the age at first operation was (35.6±14.1) years old. There were 40 patients in the reoperation group and 120 patients in the non-reoperation group. According to univariate analysis, the proportion of male gender(P=0.030), penetrating phenotype(P<0.001), history of appendectomy before the primary surgery(P=0.035) and no postoperative maintenance therapy (P<0.001) were higher in surgical recurrence group. In terms of the operation reasons, intestinal obstruction accounted for the highest proportion in the primary operation (26.9%, 43/160), while the intestinal fistula was the most common reason for reoperation (42.5%, 17/40). After the primary surgery, the cumulative reoperation rates at 1, 3, 5 and 10 years were 5.9% (9 cases), 12.3% (17 cases), 21.8% (25 cases) and 37.6% (34 cases), respectively. The ten years cumulative reoperation rate of the high-risk group was 42.8% (31 cases), which was much higher than that of low-risk group (19.8%, 3 cases), and the difference was statistically significant (P=0.006). There was no statistically significant difference in the surgical recurrence rate of low-risk group patients(P=0.076)whether maintenance therapies were added or not, while the recurrence rate of high-risk group patients who did not receive maintenance therapy was higher than those who received immunosuppressant with or without (±) 5-aminosalicylic acid (ASA) (P=0.001) and biological agent±5-ASA (P=0.001), and the difference was statistically significant. Conclusion: Patients with CD are still at risk of reoperation after surgery. Immunosuppressive agents and biologics can prevent patients from reoperation in high-risk groups.

A compact electron beam ion trap in support of high-temperature plasma diagnostics based on conduction-cooled superconducting coils

Spectroscopic diagnostics of future fusion reactor plasmas require information on impurity line emissions, especially for relevant high-Z metal elements (e.g., tungsten). These materials will be widely used as plasma facing components for their high heat tolerance and low sputtering yield. Based on an electron beam ion trap, a compact impurity spectra platform is developed to mimic the high-temperature environment of a fusion reactor. The proposed platform can deliver a focused e-beam at energies over 30 keV using a confining magnetic field of ∼1.0 T generated by two superconducting coils (NbTi). Cooled by a closed-loop cryocooler, the coils can avoid the usage of a complicated cryogenic system involving the handling of liquid helium. For spectroscopic studies of highly charged ions, a spherically curved crystal spectrometer is proposed to measure a wavelength range around 2-4 Å covering the typical wavelength range expected to be emitted by metal ions in a fusion plasma. This paper reports the design and development progress of the platform.

Ultrahigh-energy photons up to 1.4 petaelectronvolts from 12 γ-ray Galactic sources

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 plane^3-6, 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.

First Detection of sub-PeV Diffuse Gamma Rays from the Galactic Disk: Evidence for Ubiquitous Galactic Cosmic Rays beyond PeV Energies

We report, for the first time, the long-awaited detection of diffuse gamma rays with energies between 100 TeV and 1 PeV in the Galactic disk. Particularly, all gamma rays above 398 TeV are observed apart from known TeV gamma-ray sources and compatible with expectations from the hadronic emission scenario in which gamma rays originate from the decay of π^{0}'s produced through the interaction of protons with the interstellar medium in the Galaxy. This is strong evidence that cosmic rays are accelerated beyond PeV energies in our Galaxy and spread over the Galactic disk.

Development and preliminary test of a space-resolved vacuum-ultraviolet spectroscopy in EAST

The impurity radiation from the divertor region of the EAST tokamak is dominantly in the wavelength range of vacuum ultraviolet (VUV) due to the elevated edge electron temperature. A space-resolved VUV spectroscopy is developed to measure impurity radiation in the divertor region. An eagle-type VUV spectrometer with a focal length of 1 m is adopted in this system, equipped with a spherical grating and a charged-coupled device (CCD) detector. The performance of the VUV spectrometer is preliminarily tested on a synchrotron radiation facility. The wavelength calibration is conducted near 65 nm. It is found that the wavelength range observed by the CCD detector is about 11.07 nm around the central wavelength of about 65 nm. With a linear dispersion of 0.0053 nm/pixel, it is possible to measure the ion temperature lower than 20 eV at the edge region by analyzing the Doppler broadening of a carbon line. These test results show that the performance of the VUV spectrometer is capable of measuring divertor radiation and analyzing the ion temperature of edge impurity ions.

[MRI associated biomarker analysis for diagnosis of lymph node metastasis in T1-2 stage rectal cancer]

Objective: To explore the diagnostic accuracy improved by magnetic resonance imaging (MRI) biomarkers for lymph node metastasis in T1-2 stage rectal cancer before treatment. Methods: Medical records of 327 patients with T1-2 rectal cancer who underwent pretreatment MRI and rectal tumor resection between January 2015 and November 2019 were retrospectively analyzed. Fifty-seven cases were divided into the lymph node metastasis group (N+ group) while other 270 cases in the non-lymph node metastasis group (N-group) according to the pathologic diagnosis. Two radiologist evaluated the tumor characteristics of MRI images. The relationship of the clinical and imaging characteristics of lymph node metastasis was assessed by using univariate analysis and multivariable logistic regression analysis. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic abilities for the differentiation of N- from N+ tumors. Results: Among the 327 patients, MR-N evaluation was positive in 67 cases, which was statistically different from the pathological diagnosis (P<0.001). The sensitivity, specificity and accuracy of MRI for lymph node metastasis were 45.6%, 84.8% and 78.0%, respectively. Multivariate regression analysis showed that tumor morphology (P=0.002), including mucus or not (P<0.001), and MR-N evaluation (P<0.001) were independent influencing factors for stage T1-2 rectal cancer with lymph node metastasis. The area under the ROC curve of rectal cancer with lymph node metastasis analyzed by the logistic regression model was 0.786 (95%CI: 0.720~0.852). Conclusions: Tumor morphology, including mucus or not, and MR-N evaluation can serve as independent biomarkers for differentiation of N- and N+ tumors. The model combined with these biomarkers facilitates to improve the diagnostic accuracy of lymph node metastasis in T1-2 rectal cancers by using MRI.

[Relationship between matrix Gla protein and clinical features of ulcerative colitis]

Objective: To analyze the relationship between matrix Gla protein(MGP) and clinical characteristics of patients with ulcerative colitis (UC). Methods: Fifty-one UC patients who were admitted to the gastroenterology department of Peking union medical college hospital from July 1, 2015 to May 31, 2017 were included. Twenty-seven healthy subjects in the same period were included as normal controls. The expression of MGP mRNA in the colonic mucosa was detected by real-time fluorescence quantitative PCR. Clinical data of the patients were collected during a 2-year follow-up. The public data set containing MGP gene expression profile of UC patients was downloaded from the GEO database, and was divided into four groups according to the microscopic Mayo score. The differential expression of MGP in each group was analyzed. Results: All the fifty-one UC patients were followed up. The expression of MGP mRNA in the colonic mucosa of UC patients treated with hormone and immunosuppressive agents or biological agents or surgery was higher than that of patients treated with mesalazine. MGP mRNA expression was positively correlated with C-reactive protein level. It was also higher in the colonic mucosa of UC patients with clostridium difficilis or cytomegalovirus infection than that of patients without opportunistic infection. The difference of MGP mRNA expression between groups in GEO public data set was statistically significant(P<0.01), showing an up-regulation trend with the aggravation of inflammation. The expression level of MGP was moderately correlated with the microscopic Mayo score. The relationship between MGP mRNA expression and lifestyle, lesion range, erythrocyte sedimentation rate, parenteral manifestations and recurrence frequency of UC patients was not obvious. Conclusions: MGP is associated with colonic inflammation and its abnormal expression can help to predict the disease activity of patients with UC.

[Application of aldosterone/direct renin ratio before drug washout in the screening of primary aldosteronism]

Objective: To explore the cut-off point of aldosterone/direct renin ratio (ADRR) before drug washout in the screening for primary aldosteronism (PA) in the Chinese population and reduce the potential risk caused by drug washout during PA screening. Methods: Hospitalized hypertensive patients in the Hypertension Ward of Fuwai Hospital, Chinese Academy of Medical Sciences from January 2017 to October 2019 were enrolled. PA was diagnosed according to the criterion of 2016 American Guideline and 2016 Chinese Consensus for PA. The plasma aldosterone concentration (PAC), direct renin concentration (DRC) and ADRR before and after drug washout were measured. The receiver operating characteristic (ROC) curve of ADRR was drawn and the maximal Youden index was used to determine the best cut-off value. Results: A total of 542 hypertensive patients were included, with 467 patients diagnosed with essential hypertension (EHT) (297 males and 170 females), and 75 patients diagnosed with PA (51 males and 24 females). Patients with PA had higher PAC and ADRR before and after drug washout than those with EHT(150.0 (130.0, 210.0) vs 120.0 (80.0, 170.0) ng/L, 170.0 (120.0, 260.0) vs 130.0 (90.0, 180.0) ng/L; 28.9 (15.9, 63.5) vs 4.3 (1.9, 11.8) (ng/L) / (mU/L) , 55.6 (39.0, 109.0) vs 9.8 (4.5, 21.3) (ng/L) /(mU/L), all P<0.001). However, DRC of PA patients before and after washout were lower than those with EHT (4.0 (2.0, 10.0) vs 27.0 (10.0, 64.0) mU/L, 3.0 (2.0, 4.0) vs 12.2 (5.0, 27.0) mU/L, P<0.001). In EHT and PA groups, PAC and ADRR significantly increased (P=0.001, P<0.001) , but DRC significantly decreased after drug washout (all P<0.001) . The area under the ROC curve of ADRR before drug washout was 0.868 (95%CI 0.836-0.895) with the best cut-off value of 7.8 (ng/L) / (mU/L) for the screening of PA .The sensitivity and specificity was 94.7% and 66.8%, respectively, with the maximal Youden index of 0.615. Conclusion: ADRR before drug washout > 7.8 (ng/L) / (mU/L) can be used as an alternative cut-off point to screen PA when drug washout is not available.

[Association of Urinary Phenol Concentration and Blood Biochemical Indices in Coke Oven Workers]

Objective: To explore the association of urinary phenol concentration and blood biochemical indices in coke oven workers. Methods: From April to may 2019, we investigated 771 employing coke oven workers from a coke plant in Taiyuan city, and categorized into benzene-exposed group (n=402) and control group (n=369) based on their benzene exposures in workplace and urophenol concentrations. All subjects were interviewed face-to-face using a questionnaire including name, age (year) , gender, smoking and drinking habits, personal vocational history, working length (year) , and occupational protection, etc. Post-shift urine samples detected using a gas chromatography-hydrogen flame ionization detector. Fasting venous blood was drawn in the morning and centrifuged, the separated serum were detected the following items using an automatic blood biochemistry analyzer. Covariance and multiple linear regression were used to test the association of urinary phenol concentration and the levels of all the blood biochemical indices. Results: The subjects were predominantly males (n=719, 93.3%) , with an average age of (42.3±8.2) years and an average working length of (20.6±8.2) years. Compared with the control group, the benzene-exposed group were significantly different in age, working length of years, gender, smoking and drinking habits (P<0.05) . The median (interquartile interval) concentration of urinary phenol was 6.00 (0.00-33.00) μg/ml in the benzene-exposed group, which was significantly higher than that in the control group (P<0.05) . Covariance analysis indicated that the fasting blood glucose, total cholesterol and high density cholesterol in the benzene-exposed group were significantly reduced compared with the control group, yet the serum creatinine, serum uric acid and triglyceride were significantly increased (P<0.05) . Multiple linear regression showed that, an increase of each natural logarithm (Ln) transformed urinary phenol concentration was significantly associated with increases in serum uric acid level [9.82 (95%CI: 2.18-17.47) μmol/L] and cholesterol level[0.10 (95%CI:0.00-0.20) mmol/L]. An increase of each Ln-transformed accumulated benzene exposure levels was significantly associated with an increase in total cholesterol level[0.09 (95%CI: 0.01-0.17) mmol/L]. Conclusion: Occupational benzene exposure is possibly related to the variation of purine and total cholesterol metabolism in coke oven workers.

Theoretical studies of the g factors and local structures of the Ni3+ centers in Na2 Zn(SO4 )2 ·4H2 O and K2 Zn(SO4 )2 ·6H2 O crystals

The local structures and the g factors g_i (i = x, y, z) for Ni³⁺ centers in Na₂ Zn(SO₄ )₂ ·4H₂ O (DPPH) and K₂ Zn(SO₄ )₂ ·6H₂ O (PHZS) crystals are theoretically studied by using the perturbation formulas of the g factors for a 3d⁷ ion with low spin (S = 1/2) in orthorhombically compressed octahedra. In these formulas, the contributions to g factors from both the spin-orbit coupling interactions of the central ion and ligands are taken into account, and the required crystal-field parameters are estimated from the superposition model and the local geometry of the systems. Based on the calculations, the Ni-O bonds are found to suffer the axial compression δz (or Δz) of about 0.111 Å (or 0.036 Å) along the z-axis for Ni³⁺ centers in DPPH (or PHZS) crystals. Meanwhile, the Ni-O bonds may experience additional planar bond length variation δx (≈0.015 Å) along x- and y-axes for the orthorhombic Ni³⁺ center in DPPH. The theoretical g factors agree well with the experimental data. The obtained local structural parameters for both Ni³⁺ centers are discussed.

[Comparison study on sensitivity of five ophthalmic antibiotics to common drug-resistant Staphylococci on ocular surface]

Objective: To investigate the in vitro antibacterial sensitivity of levofloxacin, tobramycin, cefazolin sodium, clindamycin and fusidic acid to 67 strains of Staphylococci in ocular surface infection. The purpose of this study is to provide reference for clinical selection of drugs. Methods: Experimental study. Sixth-seven strains of drug-resistant Staphylococci isolated from the Department of Microbiology, Henan Provincial Ophthalmic Hospital during January 2018 and May 2019 were collected. There were 67 strains of Staphylococci including 28 strains of drug-resistant Staphylococcus epidermidi, 17 strains of drug-resistant Staphylococcus aureus, 15 strains of drug-resistant Staphylococcus intermedius and a few other kinds of drug-resistant Staphylococci. The minimum inhibitory concentrations (minimum inhibitory concentration, MIC) of levofloxacin, tobramycin, cefazolin sodium, clindamycin and fusidic acid in 67 strains of drug-resistant Staphylococci were determined by microliquid-based method. The sensitivity was determined according to the American CLSI-M100 standard. The statistical analysis of the data was carried out by using two-dimensional test and Fisher accurate test. Results: Fourteen strains of fusidic acid were sensitive to 17 strains of MRS-Meca-resistant Staphylococcus epidermidis, the difference between fusidic and levofloxacin is statistically significant; 14 strains of cefazolin sodium and 11 strains of fusidic acid were sensitive to 14 strains of β-Lac enzyme-producing Staphylococcus aureus, and there were significant differences between the two drugs and levofloxacin; 6 strains of cefazolin sodium and 5 strains of fusidic acid were sensitive to 10 strains of MRS-Meca-resistant Staphylococcus intermedius, as compared to levofloxacin, there were significant differences between cefazolin sodium and levofloxacin (P=0.011,0.033). Cefazolin sodium was sensitive to 5 strains of MRS-Meca-positive other drug-resistant Staphylococci, which was significantly different from levofloxacin (P=0.048); 54 and 48 strains of cefazolin sodium and fusidic acid were sensitive to 67 strains of drug-resistant Staphylococci, and the sensitive rates were 80.1% and 71.6%, respectively, which were significantly higher than those of levofloxacin, tobramycin and clindamycin. There were significant statistical differences between drug sensitivity (χ²=18.377,9.940；P=0.000,0.003). Conclusions: The sensitivity of cefazolin sodium and fusidic acid to 67 strains of drug-resistant Staphylococci is better than that of levofloxacin, tobramycin and clindamycin, these findings may provide guidance for the clinical treatment of drug-resistant Staphylococci in ocular infection. (Chin J Ophthalmol, 2020, 56: 621-625).

[Exploration of omics mechanism and drug prediction of coronavirus-induced heart failure based on clinical bioinformatics]

Objective: Present study investigated the mechanism of heart failure associated with coronavirus infection and predicted potential effective therapeutic drugs against heart failure associated with coronavirus infection. Methods: Coronavirus and heart failure were searched in the Gene Expression Omnibus (GEO) and omics data were selected to meet experimental requirements. Differentially expressed genes were analyzed using the Limma package in R language to screen for differentially expressed genes. The two sets of differential genes were introduced into the R language cluster Profiler package for gene ontology (GO) and Kyoto gene and genome encyclopedia (KEGG) pathway enrichment analysis. Two sets of intersections were taken. A protein interaction network was constructed for all differentially expressed genes using STRING database and core genes were screened. Finally, the apparently accurate treatment prediction platform (EpiMed) independently developed by the team was used to predict the therapeutic drug. Results: The GSE59185 coronavirus data set was searched and screened in the GEO database, and divided into wt group, ΔE group, Δ3 group, Δ5 group according to different subtypes, and compared with control group. After the difference analysis, 191 up-regulated genes and 18 down-regulated genes were defined. The GEO126062 heart failure data set was retrieved and screened from the GEO database. A total of 495 differentially expressed genes were screened, of which 165 were up-regulated and 330 were down-regulated. Correlation analysis of differentially expressed genes between coronavirus and heart failure was performed. After cross processing, there were 20 GO entries, which were mainly enriched in virus response, virus defense response, type Ⅰ interferon response, γ interferon regulation, innate immune response regulation, negative regulation of virus life cycle, replication regulation of viral genome, etc. There were 5 KEGG pathways, mainly interacting with tumor necrosis factor (TNF) signaling pathway, interleukin (IL)-17 signaling pathway, cytokine and receptor interaction, Toll-like receptor signaling pathway, human giant cells viral infection related. All differentially expressed genes were introduced into the STRING online analysis website for protein interaction network analysis, and core genes such as signal transducer and activator of transcription 3, IL-10, IL17, TNF, interferon regulatory factor 9, 2'-5'-oligoadenylate synthetase 1, mitogen-activated protein kinase 3, radical s-adenosyl methionine domain containing 2, c-x-c motif chemokine ligand 10, caspase 3 and other genes were screened. The drugs predicted by EpiMed's apparent precision treatment prediction platform for disease-drug association analysis were mainly TNF-α inhibitors, resveratrol, ritonavir, paeony, retinoic acid, forsythia, and houttuynia cordata. Conclusions: The abnormal activation of multiple inflammatory pathways may be the cause of heart failure in patients after coronavirus infection. Resveratrol, ritonavir, retinoic acid, amaranth, forsythia, houttuynia may have therapeutic effects. Future basic and clinical research is warranted to validate present results and hypothesis.

[Evaluation of the effect of sleep on inflammatory bowel disease patients based on propensity score matching]

Objective: To evaluate the sleep status and the correlation of sleep status with inflammatory bowel disease (IBD). Methods: A case-control study was carried out, including 568 IBD patients including 188 ucerative colitis (UC) patients and 380 Crohn's disease (CD) patients at 36 hospitals from January 1, 2018 to August 31, 2019, and 671 family members and healthy controls from the same cities. The survey consisted of three parts including general demographic data, clinical characteristics and sleep related factors by questionnaires. The items for sleep related factor included sleep duration on work days, sleep duration on weekends, sleep quality, sleep adequacy, snoring, sleep apnea and sleep hand foot movement. R language was used for propensity score and SPSS was used for statistical analysis. Results: The proportion of poor sleep quality before onset in UC and CD was higher than that in healthy control group (CD: 14.5% vs 5.3%, P<0.001; UC: 15.1% vs 5.4%, P<0.001). In CD group, the proportion of snoring before onset (31.3% vs 44.3%, P<0.001) and apnea (0.9% vs 5.5%, P=0.001) was lower than that in heathy control group. The proportion of athetosis in CD was higher than that in healthy control group (35.4% vs 28.9%, P=0.045). Conclusion: Patients with UC and CD have poor sleep quality before the onset of the disease, especially in CD patients.

[Analysis on clinical features of patients with ulcerative colitis associated colorectal cancer]

Objective: To analyze the clinical features of ulcerative colitis associated colorectal cancer (UC-CRC). Methods: A total of 869 inpatients with Ulcerative Colitis (UC) in Peking Union Medical Hospital from January 1998 to January 2018 were continuously enrolled. Clinical data and the outcome of colorectal cancer (CRC) were collected via medical records and telephone follow-up. Chi-square test and logistic regression model were used to analyze the data. Results: There were 16 patients in 869 UC inpatients who were diagnosed with CRC during a period of 7 548 person years and the incidence rate of UC-CRC was 1.84%. Compared to UC inpatients without CRC, a longer course of disease (OR=1.087, 95% CI:1.046-1.129) , a lower usage rate of 5-Aminosalicylic Acid(5-ASA) (OR=0.218, 95% CI:0.052-0.915) and a higher incidence rate of intestinal stenosis (OR=16.533, 95% CI:3.824-71.478) were found in UC inpatients with CRC. Conclusions: A long disease course is a risk factor for UC patients developing CRC, while 5-ASA therapy can reduce the risk of suffering from CRC. For UC patients with intestinal stenosis, CRC should be warned for occurring.

[A Chinese consensus statement on the clinical application of transesophageal echocardiography for critical care (2019)]

Transesophageal echocardiography(TEE) is valuable in intensive care unit (ICU) because its application meets the requirements of diagnosis and treatment of critically ill patients.However, the current application has not fully adapted to the specialty of critical care. TEE could be more valuablein ICU when used with a new way that under the guidance of the theory of critical care and embedded into the treatment workflow. We have expanded and improved the application of traditional TEE and integrated the concept of critical care, established the concept of transesophageal echocardiography for critical care (TEECC). Chinese Critical Ultrasound Study Group (CCUSG) organized experts in the area to form the consensus based the previous studiesand the long term practice of critical care ultrasound and TEE, aiming at clarifying the nature and characteristics of TEECC, promoting the rational and standardized clinical application and the coming researches.The consensus of Chinese experts on clinical application of TEECC (2019) were 33 in total, of whichthe main items were as follows: (1) TEECC is a significant means, which is expanded and improved from the traditional transesophageal echocardiography according to characteristics of critically ill patients and is applied in ICU based on critically clinical scenarios and requirements by the critical care physician, to promote visualized, refined and precisely management of critically ill patients.(2) TEE possesses distinctive superiority in implementation in ICU. It has characteristics of images with good quality, operations with good stability and low-dependent of operators, monitoring with continuity, and visualization with all-dimensional and detail of heart and blood vessels.(3)As a means of refined monitoring that could resulted in precise diagnosis and treatment, TEECC expands the dimension of intensive monitoring and improves the performance of critical care. (4) Indications of TEECC application include clinical etiological searching and invasive procedures guiding when it acted as a traditional role; and also refined hemodynamic monitoring based on critical care rationale and over-all management under specific critical clinical scenarios. (5) TEE and TTE assessments are complementary; they are not alternative. Integrated assessment of TTE and TEE is required under many critical clinical scenarios.(6) TEE should be a necessary configuration in ICU. (7) All-round and significant information regarding to the mechanism of acute circulatory disorders can be provided by TEECC; it is a non-substitutable means of identifying the causes of shock under some special clinical scenarios. (8) Focal extracardiac hematoma can be accurately and rapidly detected by TEE in patients with open-thoracic cardiac surgery or severe chest trauma when highly suspected pericardial tamponade.(9) The priority of pathophysiologic mechanism of septic shock can be rapidly and accurately identified by TEE; even if its pathophysiological changes are complex, including hypovolemia and/or vasospasm and/or left and right heart dysfunction. (10) Causes of hemodynamic disorders can be rapidly and qualitatively evaluated so that the orientation of treatment can be clarified by TEECC. (11) A full range of quantitative indicators for refined hemodynamic management in critically ill patients can be provided by TEECC. (12) TEECC helps to accurately assess volume status and predict fluid responsiveness.(13) TEECC is specially suitable for accurate quantitative assessment of cardiac function.(14) Mini TEE provides long-term continuous hemodynamic monitoring. (15) Standard views are easy to be acquired by TEECC, which is a premise for accurate and repeatable measurements, and a guarantee for assessment of effect and risk of therapy. (16) Compared with invasive hemodynamic monitoring, TEECC is minimally invasive, with low infection risk and high safety.(17) In patients with acute cor pulmonale (ACP) under condition of right ventricular dysfunction and low cardiac output, TEECC is a key tool for assessment. (18) TEECC should be implemented actively when suspicious of left to right shunt in critically ill patients who occurred hypotension that hard to explain the cause. (19) TEECC should be implemented actively when suspicious of right to left shunt in critically ill patients who occurred hypoxemia that hard to explain the cause. (20) TEECC is preferred in hemodynamics monitoring under prone position of ventilated patients.(21) TEECC is an imperative means to achieve over-all management of extracorporeal membrane oxygenation (ECMO) therapy, especially for all-round hemodynamic monitoring. (22) Three basic views is recommended to be used to simplify TEE assessment during cardiac arrest so that reversible causes could be identified, and resuscitation could be guided. (23) The flow related echodynamic evaluation (TEECC-FREE) workflow is preferred in refined hemodynamics monitoring and therapy. (24) Simple workflow of TEECC could be implemented in special critical clinical scenarios. (25) Application of TEECC is highly secure; however, impairments of procedure should also be alert by operators. (26) Pitfalls in application of TEE should be paid attention to by the critical care physician. (27) Timely and rationally application of TEECC is in favor of diagnosis and treatment of critically ill patients and may improve the prognosis.

[The value of MR T2WI signal intensity related parameters for predicting pathological complete response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer]

Objective: To evaluate the value of T2WI signal intensity related parameters that can be obtained by magnetic resonance imaging (MRI) for predicting pathological complete response (pCR) after neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanved rectal cancer (LARC). Methods: Signal Intensity of Tumor (SIT) and Signal Intensity of Tumor/Muscle (SIT/M) of MR T2WI before and after neoadjuvant chemoradiotherapy of 101 patients with locally advanced rectal cancer were evaluated by two experienced readers independently. Signal Intensity of Tumor Reduction Rate (SITRR) and Signal Intensity of Tumor/Muscle Reduction Rate (SIT/MRR) were calculated. The difference of related parameters of T2WI tumor signal intensity between the pCR and the non-pCR group were analyzed. Receiver operating characteristic (ROC) analysis was used to assess the diagnostic performance for predicting pCR. Results: Of the 101 patients, 18 were in pCR group and 83 were in non-pCR group. In all patients, the SITpre, SITpost, SITRR, SIT/Mpre, SIT/Mpost and SIT/MRR measured by reader 1 were 197.0 (133.0), 144.2 (69.7), 0.4% (0.5%), 2.6 (0.6), 3.0 (2.3) and 0.4 (0.2)% in pCR group, and 227.0 (99.0), 205 (95.4), 0.1% (0.6%), 2.6 (0.6), 2.6 (1) in non-pCR group, respectively. SITpre, SITpost, SITRR, SIT/Mpre, SIT/Mpost and SIT/MRR measured by reader 2 were 193.0 (135.0), 143.0 (69.8), 0.4% (0.2%), 2.6 (0.6), 1.5 (0.5) and 0.39% (0.2%) in pCR group, and 234.0(108.0), 203(96.5), 0.1% (0.3%), 2.6 (0.6%), 1.7 (0.7) and 0.25% (0.2%) in non-pCR group, respectively. Between the pCR and non-pCR group, there were significant differences in SITpost, SIT/Mpost and SIT/MRR measured by both readers (all P<0.01), but there was no significant differences in SITpre and SIT/Mpre (P>0.05). The difference of SITRR measured by reader 1 was not statistically significant (P=0.415), while the difference of SITRR measured by reader 2 was statistically significant (P=0.001). In patients with rectal non-mucinous adenocarcinoma, SITpost, SIT/Mpost, SITRR and SIT/MRR measured by two physicians were still statistically significant between the pCR and non-pCR group (all P<0.01), but SITpre and SIT/Mpre had no significant difference (P>0.05). ROC curve analysis showed that in all patients, the area under curve (AUC) of SITpost, SIT/Mpost and SIT/MRR for predicting pCR to neoadjuvant chemoradiotherapy in locally advanced rectal cancer was 0.694-0.762, the sensitivity was 68.2%-77.3%, and the specificity was 63.6%-77.3%. In rectal non-mucinous adenocarcinoma patients, the AUC, sensitivity and specificity was 0.704-0.764, 62.7%-78.9% and 66.2%-84.2%, respectively. Conclusions: T2WI signal intensity related parameters are potential predictors for pCR in locally advanced rectal cancer after neoadjuvant chemoradiptherapy. The predictive value is higher in non-mucinous adenocarcinoma.

[Clinical experience in the diagnosis and treatment of aortic stenosis caused by Takayasu arteritis in pediatric patients]

Objective: To analyze the clinical features and summarize the experience on the diagnosis and treatment of aortic stenosis caused by Takayasu arteritis in pediatric patients. Methods: This study was a retrospective study. Five pediatric patients diagnosed as aortic stenosis caused by Takayasu arteritis in Fuwai Hospital of Chinese Academy of Medical Sciences from January 2016 to August 2018 were included. The clinical features, methods of examination, treatment and outcome were analyzed. Results: There were 2 male and 3 female patients in this cohort. The age of onset ranged from 10 to 13 years. The main clinical symptoms were as follows: intermittent claudication and hypertension (5 patients), heart failure (3 patients). Three patients with heart failure were misdiagnosed with dilated cardiomyopathy in other hospitals. Except 1 patient died due to disease aggravation before operation, the other 4 patients received interventional therapy for severe heart failure or refractory hypertension on the basis of hormone anti-inflammatory treatment, including 2 patients treated with aortic balloon dilatation and 2 patients treated with aortic balloon dilatation and stent implantation. In post-operational follow-up, clinical symptoms and laboratory examination values of the 4 patients treated with interventional therapy were significantly improved. Conclusions: The clinical symptoms of pediatric patients with aortic stenosis caused by Takayasu arteritis mainly present with intermittent claudication, hypertension and heart failure. Aortic intervention strategy should be applied for pediatric patients with severe heart failure or refractory hypertension as early as possible.