Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A

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.

Multilayer omics landscape analyses reveal the regulatory responses of tea plants to drought stress

Adverse environments, especially drought conditions, deeply influence plant development and growth in all aspects, and the yield and quality of tea plants are largely dependent on favorable growth conditions. Although tea plant responses to drought stress (DS) have been studied, a comprehensive multilayer epigenetic, transcriptomic, and proteomic investigation of how tea responds to DS is lacking. In this study, we generated DNA methylome, transcriptome, proteome, and phosphoproteome data to explore multiple regulatory landscapes in the tea plant response to DS. An integrated multiomics analysis revealed the response of tea plants to DS at multiple regulatory levels. Furthermore, a set of DS-responsive genes involved in photosynthesis, transmembrane transportation, phytohormone metabolism and signaling, secondary metabolite pathways, transcription factors, protein kinases, posttranslational and epigenetic modification, and other key stress-responsive genes were identified for further functional investigation. These results reveal the multilayer regulatory landscape of the tea plant response to DS and provide insight into the mechanisms of these DS responses.

[Diagnosis of bacterial and viral infection by HNL, SAA, PCT and CRP combined test]

The value of combined detection of neutrophil apolipoprotein (HNL), serum amyloid A (SAA), procalcitonin (PCT) and C-reactive protein (CRP) in the differential diagnosis of bacterial and viral infectious diseases. A retrospective study was conducted to collect the clinical data of infected patients and healthy people in the clinical department of Shaanxi Provincial People's Hospital from September to December in 2022. 100 patients with confirmed infection were divided into bacterial infection group (n=50) and virus infection group (n=50), and 50 healthy people were selected as control group (n=50). Fasting venous blood was collected at the initial stage of admission or on the day of physical examination. HNL was detected by double antibody sandwich method, SAA and CRP were detected by nephelometry, and PCT was detected by chemiluminescence method. The efficacy of infection markers in the differential diagnosis of bacterial infection and viral infection in infected patients was evaluated. The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic efficacy of HNL, SAA, PCT and CRP in bacterial and viral infectious diseases; Logistic regression was used to analyze the influence of each index on the diagnostic efficiency. The results showed that the levels of HNL (126.60±33.32) ng/ml, PCT (28.02±11.37) ng/ml and CRP (36.13±14.37) mg/L in bacterial infection group were significantly higher than those of HNL (47.72±15.94) ng/ml, PCT (1.27±0.40) ng/ml, CRP (18.77±10.66) mg/L in virus group and HNL (38.21±12.53) ng/ml, PCT (0.38±0.12) ng/ml and CRP (4.13±1.07) mg/L in control group. The level of HNL increased most significantly (F=89.228, P<0.05). The area under ROC curve (AUC) from large to small was HNL+SAA+PCT+CRP (0.976), HNL (0.907), PCT (0.885), CRP (0.856), SAA (0.790), SAA/CRP (0.733). The level of SAA/CRP in virus infection group (94.05±3.75) was significantly higher than that in bacteria group (17.70±3.69) and control group (3.89±1.50) (F=84.005, P<0.05). The area under ROC curve (AUC) from large to small was HNL+SAA+PCT+CRP (0.986), SAA/CRP (0.956), SAA (0.878), HNL (0.768), CRP (0.742), PCT (0.730). In conclusion, HNL has the best auxiliary diagnostic efficacy in bacterial infection, followed by PCT; SAA/CRP has the best auxiliary diagnostic efficacy in viral infection, followed by SAA; the combined detection of serum HNL, SAA, PCT and CRP may be helpful for the differential diagnosis of bacterial and viral infections.

Cauchy non-convex sparse feature selection method for the high-dimensional small-sample problem in motor imagery EEG decoding

Introduction

The time, frequency, and space information of electroencephalogram (EEG) signals is crucial for motor imagery decoding. However, these temporal-frequency-spatial features are high-dimensional small-sample data, which poses significant challenges for motor imagery decoding. Sparse regularization is an effective method for addressing this issue. However, the most commonly employed sparse regularization models in motor imagery decoding, such as the least absolute shrinkage and selection operator (LASSO), is a biased estimation method and leads to the loss of target feature information.

Methods

In this paper, we propose a non-convex sparse regularization model that employs the Cauchy function. By designing a proximal gradient algorithm, our proposed model achieves closer-to-unbiased estimation than existing sparse models. Therefore, it can learn more accurate, discriminative, and effective feature information. Additionally, the proposed method can perform feature selection and classification simultaneously, without requiring additional classifiers.

Results

We conducted experiments on two publicly available motor imagery EEG datasets. The proposed method achieved an average classification accuracy of 82.98% and 64.45% in subject-dependent and subject-independent decoding assessment methods, respectively.

Conclusion

The experimental results show that the proposed method can significantly improve the performance of motor imagery decoding, with better classification performance than existing feature selection and deep learning methods. Furthermore, the proposed model shows better generalization capability, with parameter consistency over different datasets and robust classification across different training sample sizes. Compared with existing sparse regularization methods, the proposed method converges faster, and with shorter model training time.

Measurement of Ultra-High-Energy Diffuse Gamma-Ray Emission of the Galactic Plane from 10 TeV to 1 PeV with LHAASO-KM2A

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.

A tera-electron volt afterglow from a narrow jet in an extremely bright gamma-ray burst

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.

[The value of DISCO and MUSE-DWI combined with prostate specific antigen density in the diagnosis and risk stratification of prostate cancer]

Objective: To explore the value of differential subsampling with cartesian ordering (DISCO) and multiplexed sensitivity-encoding diffusion weighted-imaging (MUSE-DWI) combined with prostate specific antigen density (PSAD) in the diagnosis and risk stratification of prostate cancer (PCa). Methods: The data of 183 patients [aged from 48 to 86 (68±8) years] with prostate diseases in the General Hospital of Ningxia Medical University from July 2020 to August 2021 were retrospectively collected. Those patients were divided into non-PCa group (n=115) and PCa group (n=68) based on the disease condition. According to the risk degree, PCa group was subdivided into low risk PCa group (n=14) and medium-to-high risk PCa group (n=54). The differences of volume transfer constant (Ktrans), rate constant (Kep), extracellular volume fraction (Ve), apparent diffusion coefficient (ADC) and PSAD between groups were analyzed. Receiver operating characteristic (ROC) curves analysis were conducted for evaluating the diagnostic efficacy of quantitative parameters and PSAD in distinguishing non-PCa and PCa, low-risk PCa and medium-high risk PCa. Multivariate logistic regression model was used for screening out the predictors, which was statistically significant differences between non-PCa group and PCa group, for PCa prediction. Results: Ktrans, Kep, Ve and PSAD of PCa group all were higher than those of non-PCa group, and ADC value was lower than that of non-PCa group, and the differences all were statistically significant (all P<0.001). Ktrans, Kep and PSAD of medium-to-high risk PCa group all were higher than those of low risk PCa group, and ADC value was lower than that of low risk PCa group, and the differences were all statistically significant (all P<0.001). When distinguishing non-PCa from PCa, the area under ROC curve (AUC) of the combined model (Ktrans+Kep+Ve+ADC+PSAD) was higher than that of any single index [0.958 (95%CI: 0.918-0.982) vs 0.881 (95%CI: 0.825-0.924), 0.836 (95%CI: 0.775-0.887), 0.672 (95%CI: 0.599-0.740), 0.940(95%CI: 0.895-0.969), 0.816(95%CI:0.752-0.869), all P<0.05]. When distinguishing low-risk PCa and medium-to-high risk PCa, the AUC of the combined model (Ktrans+Kep+ADC+PSAD) were higher than those of Ktrans, Kep and PSAD[0.933 (95%CI: 0.845-0.979) vs 0.846 (95%CI:0.738-0.922), 0.782 (95%CI:0.665-0.873), 0.84 8(95%CI: 0.740-0.923), all P<0.05]. The multivariate logistic regression analysis showed that Ktrans (OR=1.005, 95%CI:1.001-1.010) and ADC values (OR=0.992, 95%CI:0.989-0.995) were predictors of PCa (P<0.05). Conclusions: DISCO and MUSE-DWI combined with PSAD can distinguish benign and malignant prostate lesions. Ktrans and ADC values were predictors of PCa; Ktrans, Kep, ADC values and PSAD are helpful in predicting the biological behavior of PCa.

[Neoadjuvant chemotherapy in the treatment of locally advanced olfactory neuroblastoma in 25 cases]

Objective: To evaluate the efficacy of neoadjuvant chemotherapy (NACT) in the treatment of locally advanced olfactory neuroblastoma (ONB), and to explore the factors related to the efficacy of NACT. Methods: A total of 25 patients with ONB who underwent NACT in Beijing TongRen Hospital from April 2017 to July 2022 were retrospectively analyzed. There were 16 males and 9 females, with an average age of 44.9 years (ranged 26-72 years). There were 22 cases of Kadish stage C and 3 cases of stage D. After multiple disciplinary team(MDT) discussion, all patients were treated sequentially with NACT-surgery-radiotherapy. Among them, 17 cases were treated with taxol, cis-platinum and etoposide (TEP), 4 cases with taxol, nedaplatin and ifosfamide (TPI), 3 cases with TP, while 1 case with EP. SPSS 25.0 software was used for statistical analysis, and survival analyses were calculated based on the Kaplan-Meier method. Results: The overall response rate of NACT was 32% (8/25). Subsequently, 21 patients underwent extended endoscopic surgery and 4 patients underwent combined cranial-nasal approach. Three patients with stage D disease underwent cervical lymph node dissection. All patients received postoperative radiotherapy. The mean follow-up time was 44.2 months (ranged 6-67 months). The 5-year overall survival rate was 100.0%, and the 5-year disease-free survival rates was 94.4%. Before NACT, Ki-67 index was 60% (50%, 90%), while Ki-67 index was 20% (3%, 30%) after chemotherapy [M (Q₁, Q₃)]. The change of Ki-67 before and after NACT was statistically significant (Z=-24.24, P<0.05). The effects of age, gender, history of surgery, Hyams grade, Ki-67 index and chemotherapy regimen to NACT were analyzed. Ki-67 index≥25% and high Hyams grade were related to the efficacy of NACT (all P<0.05). Conclusions: NACT could reduce Ki-67 index in ONBs. High Ki-67 index and Hyams grade are clinical indicators sensitive to the efficacy of NACT. NACT-surgery-radiotherapy is effective for patients with locally advanced ONB.

[Prognostic factors for non-small cell lung cancer patients with central nervous system metastasis with positive driver genes]

Objective: To investigate the prognostic factors of patients with central nervous system (CNS) metastatic non-small cell lung cancer (NSCLC) with positive driver genes. Methods: The clinical data of 103 patients with CNS metastatic NSCLC admitted to Beijing Tongren Hospital from January 2016 to December 2020 were retrospectively analyzed, and the patients were divided into positive driver gene group (patients with driver genes mutation and receiving corresponding targeted therapy) and negative driver gene group. Cox univariate and multivariate regression analyses were performed to identify the factors affecting patients' prognosis, and the receiver operating characteristic curve (ROC) was used to compare the predictive ability of 4 scoring systems [recursive partitioning analysis (RPA) classes, diagnosis-specific graded prognostic assessment (DS-GPA) index, basic score for brain metastasesn (BS-BM) and (lung-molecular graded prognostic assessment (lung-mol GPA)]on patients' prognosis. Results: Among the 103 patients, 48 were males and 55 were females, and aged (64.6±9.7) years old. The median survival time of the 103 patients was 24.0 (95%CI: 20.0-28.0) months, the median survival time of the 59 patients in the positive driver gene group was 33.0 (95%CI: 23.4-42.6) months, the median survival time of the 44 patients in the negative driver gene group was 17.0 (95%CI: 14.4-19.6) months, and the difference was statistically significant (χ²=24.69, P<0.001). The results of Cox multivariate analysis showed that the negative driver genes (HR=3.788, 95%CI: 1.951-7.301, P=0.001), Karnofsky performance status (KPS) score<70 (HR=2.613, 95%CI: 1.185-5.761, P=0.017) and neutrophil-to-lymphocyte ratio (NLR)>3.22 (HR=2.714, 95%CI: 1.157-6.365, P=0.022) were independent risk factors affecting the prognosis of patients with CNS metastatic NSCLC. KPS score<70 (HR=3.719, 95%CI: 1.165-11.876, P=0.027) and no radiotherapy (HR=2.032, 95%CI: 1.033-11.364, P=0.041) were independent risk factors affecting the prognosis of patients with CNS metastatic NSCLC with positive driver genes. ROC curve analysis showed that the area under curve (AUC) value of lung-mol GPA was the highest among the 4 scoring systems (AUC=0.843, 95%CI: 0.731-0.956, P<0.001), and the AUC value of the lung-mol GPA combined scoring system (AUC=0.904, 95%CI: 0.816-0.991, P<0.001) was higher than lung-mol GPA. Conclusions: A low KPS score and no cranial radiation therapy are independent risk factors for the prognosis of patients with CNS metastatic NSCLC with positive driver genes; the lung-mol GPA joint scoring system is more conducive to the prognostic assessment of patients with CNS metastatic NSCLC with positive driver genes.

Discrepancy between inter- and intra-subject variability in EEG-based motor imagery brain-computer interface: Evidence from multiple perspectives

Introduction

Inter- and intra-subject variability are caused by the variability of the psychological and neurophysiological factors over time and across subjects. In the application of in Brain-Computer Interfaces (BCI), the existence of inter- and intra-subject variability reduced the generalization ability of machine learning models seriously, which further limited the use of BCI in real life. Although many transfer learning methods can compensate for the inter- and intra-subject variability to some extent, there is still a lack of clear understanding about the change of feature distribution between the cross-subject and cross-session electroencephalography (EEG) signal.

Methods

To investigate this issue, an online platform for motor-imagery BCI decoding has been built in this work. The EEG signal from both the multi-subject (Exp1) and multi-session (Exp2) experiments has been analyzed from multiple perspectives.

Results

Firstly we found that with the similar variability of classification results, the time-frequency response of the EEG signal within-subject in Exp2 is more consistent than cross-subject results in Exp1. Secondly, the standard deviation of the common spatial pattern (CSP) feature has a significant difference between Exp1 and Exp2. Thirdly, for model training, different strategies for the training sample selection should be applied for the cross-subject and cross-session tasks.

Discussion

All these findings have deepened the understanding of inter- and intra-subject variability. They can also guide practice for the new transfer learning methods development in EEG-based BCI. In addition, these results also proved that BCI inefficiency was not caused by the subject's unable to generate the event-related desynchronization/synchronization (ERD/ERS) signal during the motor imagery.

Aroma characteristics of Wuyi rock tea prepared from 16 different tea plant varieties

Wuyi rock tea (WRT) is famous for its long history and unique characteristic of floral, fruity and nutty flavors. This study investigated the aroma characteristics of WRTs prepared from 16 different oolong tea plant varieties. The sensory evaluation results showed that all WRTs had an 'Yan flavor' taste, and the odor was strong and lasting. Roasted, floral and fruity odors were the prime aroma profiles for WRTs. Furthermore, a total of 368 volatile compounds were detected using HS-SPME-GC-MS and analyzed with OPLS-DA and HCA methods. The volatile compounds heterocyclic compounds, esters, hydrocarbons, terpenoids and ketones were the major aromatic components of the WRTs. Specifically, the volatile profiles among newly selected cultivars were comparatively analyzed, and 205 differential volatile compounds were found with variable importance in the projection (VIP) values above 1.0. These results indicated that the aroma profiles of WRTs were mainly dependent on the cultivar specificities of volatile compounds.

Constraints on Heavy Decaying Dark Matter from 570 Days of LHAASO Observations

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.

Multi-Metabolomics Coupled with Quantitative Descriptive Analysis Revealed Key Alterations in Phytochemical Composition and Sensory Qualities of Decaffeinated Green and Black Tea from the Same Fresh Leaves

The supercritical CO₂-based decaffeination (SCD) method can be used to prepare decaffeinated tea, but its overall effect on the phytochemicals, volatiles, and sensory qualities of green and black teas is still unclear, and its suitability to prepare decaffeinated green and black teas still needs to be compared. This study revealed the effect of SCD on phytochemicals, volatiles, and sensory qualities in black and green tea prepared from the same tea leaves, and compared the suitability of preparing decaffeinated green and black teas using SCD. The results showed that the SCD could remove 98.2 and 97.1% of the caffeine in green and black tea, respectively. However, it can cause further losses of phytochemicals in green and black teas, specifically the loss of epigallocatechin gallate, epigallocatechin, epicatechin gallate, and gallocatechin gallate in green tea and the loss of theanine and arginine in green and black teas. After the decaffeination, both green and black teas lost some volatiles but also generated new volatiles. Especially, the fruit/flower-like aroma, ocimene, linalyl acetate, geranyl acetate, and D-limonene, were generated in the decaffeinated black tea, while herbal/green-like aroma, β-cyclocitral, 2-ethylhexanol, and safranal, were generated in the decaffeinated green tea. The overall acceptance of decaffeinated green tea decreased due to the substantial reduction in bitterness and astringency, while the overall acceptance of decaffeinated black tea significantly increased. Therefore, SCD is more suitable for the preparation of decaffeinated black tea.

[The value of relaxation time quantitative technique from synthetic magnetic resonance imaging in the diagnosis and invasion assessment of prostate cancer]

Objective: To investigate the application value of relaxation time quantitative technique from synthetic magnetic resonance imaging (MRI) in the diagnosis and invasion assessment of prostate cancer. Methods: A total of 119 patients with prostate diseases [122 regions of interest(ROI)] who underwent routine MRI scan and magnetic resonance image compilation (MAGiC) sequence of prostate from March 2020 to March 2021 in General Hospital of Ningxia Medical University were retrospectively collected, they were divided into prostate cancer group(58 cases, 61 ROI) and non-prostate cancer group(61 cases, 61 ROI) according to the pathological results. In the prostate cancer group, those patients with an age of 48 to 85(69.8±5.9) years, and further divided into two subgroups according to the location of occurrence: peripheral zone cancer group (43 cases, 45 ROI) and transitional zone cancer group (15 cases, 16 ROI). The non-prostate cancer group consisted of patients with benign prostatic hyperplasia or complicated with chronic prostatitis, with an age of 41 to 81(68.6±7.0) years, and they were further divided into two subgroups according to the location of occurrence: non-cancerous peripheral zone group (45 cases, 45 ROI) and transitional zone benign prostatic hyperplasia group(16 cases, 16 ROI). Prostate cancer lesions were classified as low risk (Gleason score ≤6) or intermediate/high risk (Gleason score ≥7). After the post-processing of MAGiC images, T₁, T₂ and proton density(PD) values of prostate cancer group and non-prostate cancer group were obtained. At the same time, relevant software were used for image post-processing to generate apparent diffusion coefficient (ADC) value, the data between the two groups were analyzed by the Independent sample t-test or Mann-Whitney U-test, and the diagnostic effectiveness of each quantitative parameter in diagnosing prostate cancer and discriminating low risk prostate cancer from intermediate/high risk prostate cancer was analyzed by using receiver operating characteristic curve (ROC) analysis, the correlation between each quantitative parameter and Gleason score were assessed by Spearman correlation analysis. Results: The T₁ value and T₂ value of the peripheral zone cancer group were lower than those in non-cancerous peripheral zone group [1 201.3 (1 103.5, 1 298.2) ms vs 2 274.0 (1 620.9, 2 776.5) ms; 78.0 (74.0, 83.8) ms vs (160.6±54.9) ms] (all P<0.001), there was no statistically significant in PD value between the two groups (P>0.05). The T₁ value and T₂ value of the transitional zone cancer group were lower than those in transitional zone benign prostatic hyperplasia group [1 073.3 (1 003.9, 1 164.9) ms vs 1 340.8 (1 208.5, 1 502.8) ms; 76.9 (74.8, 82.8) ms vs 95.1(82.8, 103.4) ms] (all P<0.001), there was no statistically significant in PD value between the two groups (P>0.05). The area under the curve (AUC) of T₂ value was similar with the ADC value in discriminating peripheral zone cancer group from non-cancerous peripheral zone group(0.963 vs 0.991, P=0.105), while in discriminating transitional zone cancer group from transitional zone benign prostatic hyperplasia group, the AUC of T₂ value、T₁ value and ADC value were similar(0.867, 0.930 vs 0.938, all P>0.05). ADC value, T₂ value all were negatively correlated with Gleason score (r=-0.747,-0.453, all P<0.001). T₂ value and ADC value demonstrated equivalent diagnostic performance in discriminating low risk from intermediate/high risk prostate cancer, and there were no statistically significant (AUC: 0.787 vs 0.943, P=0.069). Conclusions: Quantitative relaxation time T₁ and T₂ values derived from synthetic MRI can discriminate prostate cancer from other benign pathologies, and T₂ value have the equivalent diagnostic performance compared to ADC value. Synthetic MRI has high clinical application value, and T₂ value can distinguish low risk prostate cancer from intermediate/high risk prostate cancer.

Exploring Lorentz Invariance Violation from Ultrahigh-Energy γ Rays Observed by LHAASO

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.

Triple Semicircular Canal Occlusion Combined with Endolymphatic Sac Decompression: An Effective Surgical Strategy for Vertigo Control of Intractable Meniere's Disease

Triple semicircular canal occlusion is an efficient strategy for vertigo control in patients with intractable Meniere's disease The surgery can block the movement of endolymph in the canals to eliminate vertigo attacks induced by position changing Patients with advanced stage MD suffered more from hearing deterioration postoperatively The aural fullness remission was satisfactory postoperative Vestibular rehabilitation is important and effective for vestibular function compensation, it should be recommended to all patients postoperatively.

[The prognostic value of myocardial infarct size measured by cardiovascular magnetic resonance in patients with acute ST-segment elevation myocardial infarction]

Objective: To investigate the prognostic value of infarct size (IS) in patients with acute ST-segment elevation myocardial infarction (STEMI) underwent primary percutaneous coronary intervention (PCI). Methods: A total of 104 patients with acute STEMI who underwent primary PCI treatment in Shengjing Hospital of China Medical University from February 2017 to November 2018 were included in the present study. All patients underwent cardiovascular magnetic resonance (CMR) within one week after primary PCI treatment. The subjects were followed up for two years. Major adverse cardiac events (MACE) included new onset congestive heart failure and/or recurrent nonfatal myocardial infarction and/orcardiac death. The optimal IS cutoff value for MACE was determined by receiver operating character (ROC) curve. Based on the IS cutoff value, the patients were divided into the high IS group and the low IS group. Clinical characteristics between the two groups were compared. A cox regression model was used to analyze the prognostic value of IS in acute STEMI patients treated with primary PCI for the adverse events. Results: The IS cutoff value determined by ROC curve was 13.55%. 50 patients were in the high IS group (IS≥13.55%) and 54 patients were in the low IS group (IS<13.55%). More female patients [14 cases (28.0%) vs. 6 cases (11.1%)] were in the IS group, and a higher proportion of patients in the high IS group had anterior myocardial infarction [27 cases (54.0%) vs. 16 cases (29.6%)] or microvascular obstruction [32 cases (64.0%) vs. 16 cases (29.6%)]. White blood cell counts [11.25(8.90, 13.38) ×10⁹/L vs. 9.25(7.58, 11.00) ×10⁹/L], troponin I levels [50.63(16.56, 76.30)μg/L vs. 16.58(2.66, 38.42)μg/L] and brain natriuretic peptide levels [178.10(79.70, 281.95)μg/L vs. 79.60(42.83, 183.90)μg/L] in the high IS group were higher than those in the low IS group (P<0.05), and left ventricular ejection fraction [(45.15±10.65)% vs. (51.95±12.91)%] in the high IS group was lower than that in the low IS group (P<0.05). Multivariate Cox regression analyses showed that IS was independently associated with the risk of cardiac death in patients with acute STEMI two years after primary PCI(P=0.033, HR=1.075, 95%CI1.006-1.148). Every 1% increase in IS was associated with a 7.5% increase in cardiac death. Conclusions: Infarct size, measured by CMR within one week after primary PCI, is strongly associated with cardiac death in patients with acute STEMI two years after primary PCI. IS could be used as an index for the prognosis of patients with acute STEMI.

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.

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.

Effect of brewing conditions on phytochemicals and sensory profiles of black tea infusions: A primary study on the effects of geraniol and β-ionone on taste perception of black tea infusions

As a worldwide popular drink, black tea has always been one of the main focuses of tea studies. However, few studies have addressed the flavor profiles and related components, and most researches were based on a single factor. This study investigated the effects of multiple brewing conditions (temperature, time, water/tea ratio, and particle size) on the phytochemicals (non-volatile and volatile compounds) and sensory profiles of black tea infusions through response surface methodology. The regression models describing the brewing of detected indexes were significant (p ≤ 0.01) and reliable (R² ≥ 0.902). The particle size led to the greatest variation of non-volatile compounds and presented negative correlations, while the water/tea ratio affected the composition of volatile compounds the most. Meanwhile, through the addition of the selected aroma compounds (geraniol and β-ionone), an enhancement of black tea infusion sweetness was observed, proved the existence of odor-taste interaction in black tea infusions.

[A single-arm prospective study on induction chemotherapy and subsequent comprehensive therapy for advanced hypopharyngeal squamous cell carcinoma: report of 260 cases in a single center]

Objective: To study the significance of induction chemotherapy and subsequent comprehensive therapy for overall survival rate (OS) and larynx dysfunction-free survival rate (LDFS) in patients with advanced hypopharyngeal carcinoma. Methods: Patients who met the inclusion criteria with the diagnoses of advanced hypopharyngeal carcinoma between 2011 and 2017 received 2 or 3 cycles of TPF regimen induction chemotherapy. Patients who attained complete response (CR) received radical chemotherapy. Patients who attained partial response (PR) and the reduction of tumor volume was more than 70% were defined as large PR and received concurrent chemoradiotherapy. When the tumor volume reduction of PR patients was less than 70%, they were defined as small PR. (CR+large PR) group was defined as effective group. Patients who did not reach CR and large PR were defined as uneffective group and underwent radical surgery and received adjuvant radiotherapy as appropriate after the surgery. The end points of the study were OS, progression-free survival (PFS) and LDFS. Chi-square (χ(2)) test was used for correlation analysis. Survival analysis was performed by the Kaplan-Meier method with a Log-rank test. Cox proportional hazards model was used for univariate and multivariate survival analysis. Results: A total of 260 patients were enrolled in the study. The follow-up period ranged from 5 to 83 months, with an average of 24.7 months. The 3-year and 5-year OS rate was 46.0% and 32.6%, respectively. The 3-year and 5-year PFS rate was 41.0% and 26.6%, respectively. The 3-year and 5-year LDFS rate was 37.9% and 24.8%, respectively. Poor outcome of induction chemotherapy, advanced N stage, strong positive Ki-67 immunohistochemistry (all P<0.001) were negative prognostic factors. The advanced clinical stage was positively related to the poor outcome of induction chemotherapy (P=0.015). There was no significant difference in OS and PFS between the large PR group and the small PR group (all P>0.005). Conclusion: TPF regimen induction chemotherapy and subsequent comprehensive therapy for patients with advanced hypopharyngeal carcinoma may improve the quality of life of patients, with high OS rate and LDFS rate.

The CSP-Based New Features Plus Non-Convex Log Sparse Feature Selection for Motor Imagery EEG Classification

The common spatial pattern (CSP) is a very effective feature extraction method in motor imagery based brain computer interface (BCI), but its performance depends on the selection of the optimal frequency band. Although a lot of research works have been proposed to improve CSP, most of these works have the problems of large computation costs and long feature extraction time. To this end, three new feature extraction methods based on CSP and a new feature selection method based on non-convex log regularization are proposed in this paper. Firstly, EEG signals are spatially filtered by CSP, and then three new feature extraction methods are proposed. We called them CSP-wavelet, CSP-WPD and CSP-FB, respectively. For CSP-Wavelet and CSP-WPD, the discrete wavelet transform (DWT) or wavelet packet decomposition (WPD) is used to decompose the spatially filtered signals, and then the energy and standard deviation of the wavelet coefficients are extracted as features. For CSP-FB, the spatially filtered signals are filtered into multiple bands by a filter bank (FB), and then the logarithm of variances of each band are extracted as features. Secondly, a sparse optimization method regularized with a non-convex log function is proposed for the feature selection, which we called LOG, and an optimization algorithm for LOG is given. Finally, ensemble learning is used for secondary feature selection and classification model construction. Combing feature extraction and feature selection methods, a total of three new EEG decoding methods are obtained, namely CSP-Wavelet+LOG, CSP-WPD+LOG, and CSP-FB+LOG. Four public motor imagery datasets are used to verify the performance of the proposed methods. Compared to existing methods, the proposed methods achieved the highest average classification accuracy of 88.86, 83.40, 81.53, and 80.83 in datasets 1–4, respectively. The feature extraction time of CSP-FB is the shortest. The experimental results show that the proposed methods can effectively improve the classification accuracy and reduce the feature extraction time. With comprehensive consideration of classification accuracy and feature extraction time, CSP-FB+LOG has the best performance and can be used for the real-time BCI system.

Parotidectomy in the management of squamous cell carcinoma of the external auditory canal

PURPOSE

To investigate optimal approaches for appropriate removal of the parotid gland in the management of squamous cell carcinoma (SCC) of the external auditory canal (EAC) at different tumor stages.

METHODS

In total, 39 patients with SCC of EAC treated at the Second Affiliated Hospital of Nanchang University between September 2003 and April 2019 were enrolled in this study. All patients underwent lateral temporal bone resection or subtotal temporal bone resection. Total parotidectomy was performed in patients with direct parotid invasion. Superficial parotidectomy was performed in patients with parotid node metastasis and patients with advanced stages without evidence of parotid involvement.

RESULTS

The mean follow-up period was 68.7 months. Local recurrences or distant metastases occurred in five patients (12.8%). The 5-year overall survival rate was 78.4%. The 5-year survival rate was 100% in early stage (T₁ and T₂) patients, and 58.9 and 50.0% in patients staged III and IV, respectively. Direct parotid invasion was observed in only advanced-stage patients, while parotid node metastasis was noted in both early and advanced-stage patients preoperatively. There were no significant differences (χ² = 0.1026; p = 0.749) between different tumor primary locations. However, soft tissue or preauricular organs became vulnerable once the anterior wall was infiltrated or eroded.

CONCLUSION

Parotid management is important for achieving safer and wider tumor-free margins. Total parotidectomy should be mandatory for all advanced-staged (T₃ and T₄) patients. An optimal decision for parotid management in early stages depends on the infiltration or erosion of the anterior wall of the EAC.

Segmentation of small ground glass opacity pulmonary nodules based on Markov random field energy and Bayesian probability difference

BACKGROUND

Image segmentation is an important part of computer-aided diagnosis (CAD), the segmentation of small ground glass opacity (GGO) pulmonary nodules is beneficial for the early detection of lung cancer. For the segmentation of small GGO pulmonary nodules, an integrated active contour model based on Markov random field energy and Bayesian probability difference (IACM_MRFEBPD) is proposed in this paper.

METHODS

First, the Markov random field (MRF) is constructed on the computed tomography (CT) images, then the MRF energy is calculated. The MRF energy is used to construct the region term. It can not only enhance the contrast between pulmonary nodule and the background region, but also solve the problem of intensity inhomogeneity using local spatial correlation information between neighboring pixels in the image. Second, the Gaussian mixture model is used to establish the probability model of the image, and the model parameters are estimated by the expectation maximization (EM) algorithm. So the Bayesian posterior probability difference of each pixel can be calculated. The probability difference is used to construct the boundary detection term, which is 0 at the boundary. Therefore, the blurred boundary problem can be solved. Finally, under the framework of the level set, the integrated active contour model is constructed.

RESULTS

To verify the effectiveness of the proposed method, the public data of the lung image database consortium and image database resource initiative (LIDC-IDRI) and the clinical data of the Affiliated Jiangmen Hospital of Sun Yat-sen University are used to perform experiments, and the intersection over union (IOU) score is used to evaluate the segmentation methods. Compared with other methods, the proposed method achieves the best results with the highest average IOU of 0.7444, 0.7503, and 0.7450 for LIDC-IDRI test set, clinical test set, and all test sets, respectively.

CONCLUSIONS

The experiment results show that the proposed method can segment various small GGO pulmonary nodules more accurately and robustly, which is helpful for the accurate evaluation of medical imaging.

Middle ear adenomatous neuroendocrine tumors: suggestion for surgical strategy

Introduction

Middle ear adenomatous neuroendocrine tumors are extremely rare neoplasms with epithelial and neuroendocrine differentiation, accounting for fewer than 2% of all middle and inner ear tumors. Universal standard surgical procedures for different stages of these tumors remain elusive due to the limitation of the small number of case reports or investigations.

Objective(s)

This study intends to investigate proper surgical strategies for patients with middle ear adenomatous neuroendocrine tumors.

Methods

Six patients with middle ear adenomatous neuroendocrine tumors who were treated at the Second Affiliated Hospital of Nanchang University (Nanchang, China) and the Eye, Ear, Nose, and Throat Hospital of Fudan University (Shanghai, China) respectively. Clinical characteristics and management strategies of patients were reviewed. The mean follow-up time was 63.7 months (range, 13–153 months). All the information was collected from medical records and prognosis postoperatively.

Results

Three patients underwent canal wall-up tympanomastoidectomy, including one patient with recurrence who underwent a previous tympanotomy; the other three patients underwent lateral temporal bone resection All of these patients were followed up with no evidence of recurrence or metastasis. Patients underwent canal wall-up surgery treatment accompanied with hearing function preservation measurements during follow-up periods.

Conclusions

Complete surgical resection provided good results for patients with middle ear adenomatous neuroendocrine tumors. The ossicular chain should be removed. Because of the propensity for local recurrence and invasiveness, as well as regional or distant metastasis of these tumors, it is necessary to schedule long-term follow-up and an observation plan postoperatively.

[Basal squamous cell carcinoma of external auditory meatus: a case report]

Summary The patient developed repeated itching and scabbing at the mouth of the left external auditory canal 5 years ago. In the last two years, the tumor is enlarged. After admission, the left external auditory canal can be seen as a reddish mass, brittle and easy to bleed. CT of temporal bone showed that the soft tissue shadow of left external auricle and external auditory canal was thickened. Postoperative pathological findings: (left external auditory canal) basal cell squamous cell carcinoma. According to the history, physical examination and laboratory examination, the diagnosis is considered as basal squamous cell carcinoma of the external auditory meatus.

Succession Law of Intestinal Flora after Death in SD Rats

OBJECTIVES

To initially explore the sequential changes in the intestinal flora of corpse for the estimation of postmortem interval （PMI）.

METHODS

Rats were sacrificed by cervical dislocation, and samples were taken from their intestines using cotton swab to extract the DNA of intestinal flora. The 16S rRNA V3 universal primers were selected for PCR, and the PCR products were used for denatured gradient gel electrophoresis. The diversity and similarity analysis of intestinal flora were analyzed between groups, and the bands were cut from denaturing gradient gel electrophoresis. After purification, PCR and sequencing, the percentage of major bacteria in each group was obtained.

RESULTS

The flora diversity showed a reduced tendency from 1st to 30th day after death （ P<0.05）, while the intra-group similarity showed a downward trend （ P<0.05）. The number of bands and intra-group similarity coefficient （Cs） on the first day was higher than that of other groups （ P<0.05）. The intra-group Cs of the 25th and 30th day had a significant difference compared with the 5th day （ P<0.05）. At the genus level, the intestinal flora was mainly composed of Enterococcus sp. on the 1th and 5th day after death, Bacillus thuringienssis was the dominant species on the 10th, 15th and 20th day, and Enterococcus faecalis became the dominant species on the 25th and 30th day.

CONCLUSIONS

The composition and structure of intestinal flora change significantly in rats with the time after death, which indicates that the succession of intestinal flora is related to the postmortem interval.

[The therapeutic effect of HSV1-hGM-CSF combined with doxorubicin on the mouse breast cancer model]

Objective: To evaluate the oncolytic effect of herpes simplex virus type 1 which carried recombined human granulocyte-macrophage colony-stimulating factor (HSV1-hGM-CSF) on the mouse breast cancer cell line 4T1 and compare the anticancer effects of HSV1-hGM-CSF, doxorubicin alone or combination on the breast cancer in mice. Methods: We investigated the cytotoxic effect on 4T1 cells in vitro, the cell growth, cell apoptosis and cell cycle of 4T1 cells treated with oncolytic HSV1-hGM-CSF at different MOIs (0, 0.5, 1 and 2) and doxorubicin at different concentrations (0, 2, 4 and 8 μg/ml). The effects of oncolytic HSV1-hGM-CSF and doxorubicin on the tumor growth, survival time and their side effects on the mouse breast cancer model were observed. Results: Both oncolytic HSV1-hGM-CSF and doxorubicin significantly inhibited the proliferation of 4T1 cells in vitro. Doxorubicin induced the G(2)/M phase arrest of 4T1 cells, while the cytotoxicity of oncolytic HSV1-hGM-CSF was no cell cycle-dependent.At day 16 after treatment with doxorubicin and HSV1-hGM-CSF, the tumor volume of 4T1 tumor bearing mice were (144.40±27.68)mm(3,) (216.80±57.18)mm(3,) (246.10±21.90)mm(3,) (327.50±44.24)mm(3,) (213.30±32.31)mm(3) and (495.80±75.87)mm(3) in the groups of doxorubicin combined with high dose HSV1-hGM-CSF, doxorubicin combined with low dose HSV1-hGM-CSF, doxorubicin alone, high dose HSV1-hGM-CSF alone, low dose HSV1-hGM-CSF alone and control, respectively.Compared with the control group, both doxorubicin and HSV1-hGM-CSF treatment exhibited significant reduction of primary tumor volume in vivo (P<0.001). The median survival times were 48, 50, 40, 42, 43 and 37 days in the six groups mentioned above, respectively. The median survival period of doxorubicin alone, high dose HSV1-hGM-CSF alone and low dose HSV1-hGM-CSF alone were significantly longer than that of control (P<0.05). Conclusion: Synergistic effect of sequential treatment with doxorubicin and oncolytic HSV1-hGM-CSF is observed in 4T1 mouse breast cancer.

MicroRNA-let-7e regulates the progression and development of allergic rhinitis by targeting suppressor of cytokine signaling 4 and activating Janus kinase 1/signal transducer and activator of transcription 3 pathway

The present study aimed to explore the microRNA-let-7e (miR-let-7e) expression in allergic rhinitis (AR), and to investigate the underlying molecular mechanisms. miR-let-7e expression in the nasal mucosa of mice and patients with AR were detected. The expression levels of three inflammatory factors, including histamine, immunoglobulin E and tumor necrosis factor-α (TNF-α), in the blood of AR mice and in interleukin (IL)-13-stimulated nasal epithelial cells (NECs) were also measured. Furthermore, the target gene of miR-let-7e was predicted and validated using a luciferase reporter assay. The expression levels of Janus kinase 1 (JAK1) and signal transducer and activator of transcription 3 (STAT3) were detected. The results demonstrated that miR-let-7e was downregulated in patients and mice with AR compared with the controls. In addition, the expression levels of inflammatory factors were higher in the blood of mice with AR compared with the control group, while miR-let-7e overexpression inhibited these levels in AR mice and IL-13-stimulated NECs. Furthermore, suppressor of cytokine signaling 4 (SOCS4) was revealed as a potential target gene of miR-let-7e and was negatively regulated by miR-let-7e. Overexpression of SOCS4 abrogated the anti-inflammatory activity of miR-let-7e overexpression. Finally, miR-let-7e overexpression activated the JAK1/STAT3 signaling pathway. In conclusion, miR-let-7e may serve an important role in the progression and development of AR, while overexpression of miR-let-7e had an anti-inflammatory effect by targeting SOCS4, which may be achieved by activation of the JAK1/STAT3 signaling pathway.

Misfit Strain Relaxation of Ferroelectric PbTiO3/LaAlO3 (111) Thin Film System

Ferroelectric thin films grown on high index substrates show unusual structural and switching dynamics due to their special strain states. Understanding the misfit relaxation behavior is crucial to facilitate the high index thin film growth with improved quality. In this paper, ferroelectric PbTiO₃ thin films were grown on LaAlO₃ (111) substrates by pulsed laser deposition technique. The microstructures were investigated by combinations of conventional and aberration-corrected transmission electron microscopy. Diffraction contrast analysis and high resolution imaging reveal that high density interfacial dislocations were distributed at the interfaces. These dislocations have mixed character with Burgers vectors of a <110> and line directions of <112>. The edge components of the dislocations, with the Burgers vectors parallel to the interface, accommodate the lattice mismatch and are the main contributor to the misfit relaxation of this system. The formation mechanism of these dislocations is proposed and discussed to elucidate the novel mismatch relaxation behavior of <111> oriented perovskite films.

Long noncoding RNA PVT1 promotes cervical cancer progression through epigenetically silencing miR-200b

Long noncoding RNA PVT1 has been reported to be dysregulated and play vital roles in a variety of cancers. However, the functions and molecular mechanisms of PVT1 in cervical cancer remain unclear. The objective of this study was to investigate the expression, clinical significance, biological roles, and underlying functional mechanisms of PVT1 in cervical cancer. Our results revealed that PVT1 is upregulated in cervical cancer tissues. Enhanced expression of PVT1 is associated with larger tumor size, advanced International Federation of Gynecology and Obstetrics stage, and poor prognosis of cervical cancer patients. Using gain-of-function and loss-of-function approaches, we demonstrated that overexpression of PVT1 promotes cervical cancer cells proliferation, cell cycle progression and migration, and depletion of PVT1 inhibits cervical cancer cell proliferation, cell cycle progression, and migration. Mechanistically, we verified that PVT1 binds to EZH2, recruits EZH2 to the miR-200b promoter, increases histone H3K27 trimethylation level on the miR-200b promoter, and inhibits miR-200b expression. Furthermore, the effects of PVT1 on cervical cell proliferation and migration depend upon silencing of miR-200b. Taken together, our findings confirmed that PVT1 functions as an oncogene in cervical cancer and indicated that PVT1 is not only an important prognostic marker, but also a potential therapy target for cervical cancer.

Thymic stromal lymphopoietin polymorphisms and allergic rhinitis risk: a systematic review and meta-analysis with 6351 cases and 11472 controls

Previous studies suggested a close association between the thymic stromal lymphopoietin (TSLP) genetic variants and allergic diseases. Here, we explored the correlation between the TSLP polymorphisms and allergic rhinitis susceptibility using meta-analysis. We searched PubMed, Ovid, Cochrane libraries, CNKI, Wanfang, and CQVIP databases until Apr 19, 2015. Quality assessment was conducted for each article according to the Strengthening the Reporting of Genetic Association studies (STREGA). The pooled measure was calculated as the inverse variance-weighted mean of the logarithm of the OR with 95% CI to assess the strength of association between TSLP polymorphisms and the risk of allergic rhinitis. Five case-control studies with 6351 cases and 11472 controls were included in this study. TSLP rs1898671 polymorphism was significantly associated with an increased risk of allergic rhinitis (OR=1.13; 95% CI, 1.07-1.20; P<0.0001). In the subgroup analysis by race, TSLP rs1898671 polymorphism was significantly associated with an increased risk of allergic rhinitis in Caucasian (OR=1.14; 95% CI, 1.08-1.21; P<0.00001). In the subgroup analysis by age group, adult individuals with TSLP rs1898671 polymorphism showed increased risk of allergic rhinitis (OR=1.13; 95% CI, 1.07-1.21; P<0.0001). Because only one study investigated the association between other SNPs in TSLP and allergic rhinitis risk, the meta-analyses were not performed. In summary, we demonstrated that TSLP rs1898671 polymorphism was associated with a higher risk for allergic rhinitis.

Long noncoding RNA-LET, which is repressed by EZH2, inhibits cell proliferation and induces apoptosis of nasopharyngeal carcinoma cell

Recent studies have reported that long noncoding RNAs (lncRNAs) play critical roles in carcinogenesis and progression. LncRNA-LET, a recently identified lncRNA, has been shown to be a tumor suppressor in hepatocellular carcinoma. However, the expression and functional of lncRNA-LET in other type of cancers remain largely unknown. In this study, we found that lncRNA-LET was significantly downregulated in nasopharyngeal carcinoma (NPC) tissues compared with corresponding normal tissues. Decreased LET expression is significantly correlated with advanced clinical stage, larger tumor size, increased lymph node tumor burden, and poor survival of NPC patients. Gain- and loss-of-function experiments demonstrated that enhanced LET expression inhibited NPC cells proliferation and induced cell apoptosis. By contrast, the knockdown of LET promoted NPC cells proliferation and inhibited cell apoptosis. Importantly, we found lncRNA-LET is transcriptional repressed by EZH2-mediated H3K27 histone methylation on the LET promoter. The expressions of EZH2 and lncRNA-LET are significantly inversely correlated in NPC tissues. Collectively, these findings indicate a pivotal role for lncRNA-LET in NPC cell proliferation and apoptosis, and reveal an epigenetic mechanism for lncRNA-LET dysregulation.

Analysis of cell cycle shortening and developmental interruption in Dictyostelium discoideum allC RNAi mutants

Dictyostelium discoideum allC RNAi mutant cells are motile and aggregate together, but do not undergo further morphological development. The relatively quick growth rate of allC RNAi mutants compared to wild-type D. discoideum results in a shortened mutant cell cycle. However, at present, little is known about the mechanism underlying this phenomenon. Here, we used semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR), real-time quantitative RT-PCR, two-dimensional gel electrophoresis, and mass spectrometry/mass spectrometry to elucidate the phenomenon. We found significant downregulation of myosin II heavy chain, D. discoideum calcium-dependent cell adhesion molecule-1 (DdCAD-1) mRNA, DdCAD-1 protein, D. discoideum mRNA for 14-3-3 and 14-3-3 protein, and type A von Willebrand factor domain-containing protein mRNA in allC RNAi mutants. The results suggest that downregulation of the myosin II heavy chain could be one of key factors causing the developmental interruption and that downregulation of the 14-3-3 protein and the type A von Willebrand factor domain-containing protein mRNA plays an important role in shortening the cell cycle of allC RNAi mutants.

[Surgical methods and clinical analysis of early-stage glottic carcinoma involved anterior commissure]

OBJECTIVE

To explore the surgical methods for management of early-stage glottic carcinoma involved anterior commissure.

METHOD

Fifty-eight cases of early-stage glottic carcinoma (T1, n = 23; T2, n = 35) treated with vertical frontolateral partial laryngectomy and frontal partial laryngectomy or modified window partial laryngectomy without tracheostomy were retrospectively reviewed.

RESULT

All patients can swallow smoothly and phonate clearly after operation. And the extubation rate with vertical fronto vertical partial laryngectomy is 97.2%. Tracheostomy was performed in one case after operation because of dyspnea. The most common postoperative complication was subcutaneous emphysema which developed postoperatively in 6 patients, but subsided after discharge. Follow-up was conducted for 8 months to 7 years, recurrence was observed in 3 cases. The 3 and 5 year survival rates were 97.5% and 91.8% respectively.

CONCLUSION

To choose the optimal surgical method for patients with early-stage glottic carcinoma not only can reduce the risk of recurrence but also can save the laryngeal function and thus improves the quality of life.

[The expression of oncogene AKT2 in laryngeal squamous cell carcinoma and its clinical significance]

OBJECTIVE

To investigate the expression and clinical significance of oncogene AKT2 in laryngeal squamous cell carcinoma (LSCC).

METHOD

The expression of AKT2 protein was measured with immunohistochemistry (Elivision two steps) in 60 cases of LSCC tissue, 28 cases of peri-cancer tissue and 16 cases of normal laryngeal epithelium, the relationship between AKT2 expression and clinical pathologic factors in LSCC was also analyzed.

RESULT

The positive rates of AKT2 protein expression in LSCC and peri-cancer tissue were 56.7% (34/60), 14.3% (4/28) respectively. There was no expression of AKT2 in normal laryngeal epithelium. The positive rate of AKT2 protein expression in LSCC was significantly higher than that in peri-cancer tissue and normal laryngeal epithelium (P < 0.05, respectively). The positive rate of AKT2 was correlated with tumor site, lymph node metastasis and clinical stage of LSCC (P < 0.05, respectively), but wasn't correlated with patient's age, sex, and T stage (P > 0.05, respectively).

CONCLUSION

AKT2 might play an important role in the tumorigenesis and development of LSCC, and it was suggested that AKT2 could be a useful marker for predicting tumorigenesis, invasion and metastasis potential of LSCC.

[Construction and identification of exogenous gene expression system in Lactococcus lactis]

OBJECTIVE

To construct and characterize an exogenous gene expression system in Lactococcus lactis.

METHODS

PCR-based gene assembly was used to synthesize the gene sequence containing P59 promoter, USP45 signal peptide, ribosome binding site and multiple cloning site. Plasmid pBS-pu was obtained after ligation of the assembled sequence with pBluescript II SK (+), and the terminator of USP45 protein was added to construct the recombinant plasmid pNBC1000. The gene coding for Streptococcus pyogenes M6 protein was amplified and cloned into pNBC1000 to obtain the plasmid pNBC2000. To characterize the expression system, enhanced green fluorescent protein (EGFP) gene was amplified from the plasmid pEGFP-N1 and cloned into pNBC2000. Laser scanning confocal microscope was used to observe the bacteria containing pNBC2000, pNBC2000-EGFP or pBS-EGFP.

RESULTS

Green fluorescence was visualized in the bacteria containing pNBC2000-EGFP, but not in the bacteria containing pNBC2000 or pBS-EGFP.

CONCLUSION

The plasmids pNBC1000 and pNBC2000 containing P59 promoter, USP45 signal peptide, ribosome binding site and multiple cloning sites are successfully constructed, which are capable of expressing exogenous gene in Lactococcus lactis.

Adjusting Lung Cancer Risks for Temporal and Spatial Variations in Radon Concentration in Dwellings in Gansu Province, China

Our recent study in Gansu Province, China reported an increasing risk of lung cancer with increasing residential radon concentration that was consistent with previous pooled analyses and with meta-analyses of other residential studies (Wang et al., Am. J. Epidemiol. 155, 554-564, 2002). Dosimetry used current radon measurements (1-year track-etch detectors) in homes to characterize concentrations for the previous 30 years, resulting in uncertainties in exposure and possibly reduced estimates of disease risk. We conducted a 3-year substudy in 55 houses to model the temporal and spatial variability in radon levels and to adjust estimates of radon risk. Temporal variation represented the single largest source of uncertainty, suggesting the usefulness of multi-year measurements to assess this variation; however, substantial residual variation remained unexplained. The uncertainty adjustment increased estimates of the excess odds ratio by 50-100%, suggesting that residential radon studies using similar dosimetry may also underestimate radon effects. These results have important implications for risk assessment.

[Antisecretory effect of dl-(15R)-15 methyl-PGE2 methyl ester (PG6E) on perfusing rats in vivo]

The antisecretion effect of dl-(15R)-15 methyl-PGE2 methyl ester (PG6E) was studied in perfusing rats in vivo. The results showed that PG6E at the dose 0.1 mg.kg-1 decreased markedly the acid secretion and antagonized the gastric acid secretion induced by histamine, pilocarpin and pentagastrin in rats. This action of PG6E appeared to be similar to that of cimetidine (40 mg.kg-1).

[Use of high-field nulear magnetic resonance spectroscopy for the analysis of stereoselective metabolites of ibuprofen (R)-enantiomer in rat urine]

AIM

To study the metabolic chiral inversion and chiral metabolites of R-(-)-ibuprofen.

METHODS

Following administration of R-(-)-ibuprofen (250 mg.kg-1), analysis was performed on rat urine purified extracts obtained by solid phase extraction onto C-18 bonded silica gel, then the metabolites of ibuprofen were detected and identified by 1HNMR spectroscopy.

RESULTS

Except for a little ibuprofen, there were 2'-hydroxy-ibuprofen and its glucuronide, 1'-carboxy-ibuprofen glucuronide and ibuprofen glucuronide in rat urine. 2'-hydroxy-ibuprofen is the main metabolite. 1'-carboxy-ibuprofen glucuronide and ibuprofen glucuronide were diastereoisomers.

CONCLUSION

There was the phenomenon of metabolic chiral inversion, whereby the R-enantiomer is transformed in vivo to its active S-antipode via an unusual process.

Lung cancer and environmental tobacco smoke in a non-industrial area of China

We report results from a population-based case-control study of lung cancer and environmental tobacco smoke (ETS) among never-smokers conducted in 2 rural prefectures of China, including 200 female and 33 male lung cancer cases, and 407 female and 114 male controls, matched on age, sex and prefecture of current residence. The odds ratio (OR) for ever-exposed to ETS was 1.19 (95% CI 0.7-2.0), with a significant trend (p<0.05) with increasing exposure. ORs were 1.00, 1.04, 1.13 and 1.51 for non-exposed, <10, 10-19 and >/=20 pack-years of ETS exposure, respectively. Excess risks were limited to ETS exposures in childhood (</=18 years of age). The OR for ever-exposed to ETS in childhood, adjusting for ETS exposure in adulthood, was 1. 52 (95% CI 1.1-2.2), with a significant trend (p<0.01) with increasing pack-years of childhood exposure, 1.00, 1.43, 1.81 and 2. 95, respectively. After adjustment for ETS in childhood, there was no excess risk from adult ETS exposure. The OR for ever-exposed to ETS in adulthood was 0.90 (95% CI 0.-1.4). These results were not affected by adjustment for type of residential dwelling, type or amount of fuel used, perceived indoor smokiness, or measures of socioeconomic status, or omitting next-of-kin respondents.

Lung cancer and environmental tobacco smoke in a non-industrial area of China

We report results from a population-based case-control study of lung cancer and environmental tobacco smoke (ETS) among never-smokers conducted in 2 rural prefectures of China, including 200 female and 33 male lung cancer cases, and 407 female and 114 male controls, matched on age, sex and prefecture of current residence. The odds ratio (OR) for ever-exposed to ETS was 1.19 (95% CI 0.7-2.0), with a significant trend (p<0.05) with increasing exposure. ORs were 1.00, 1.04, 1.13 and 1.51 for non-exposed, <10, 10-19 and >/=20 pack-years of ETS exposure, respectively. Excess risks were limited to ETS exposures in childhood (</=18 years of age). The OR for ever-exposed to ETS in childhood, adjusting for ETS exposure in adulthood, was 1. 52 (95% CI 1.1-2.2), with a significant trend (p<0.01) with increasing pack-years of childhood exposure, 1.00, 1.43, 1.81 and 2. 95, respectively. After adjustment for ETS in childhood, there was no excess risk from adult ETS exposure. The OR for ever-exposed to ETS in adulthood was 0.90 (95% CI 0.-1.4). These results were not affected by adjustment for type of residential dwelling, type or amount of fuel used, perceived indoor smokiness, or measures of socioeconomic status, or omitting next-of-kin respondents.

[Protection of dl-(15R)-15 methyl-PGE2 methyl ester (PG6E) on experimental ulcers in rats]

The effects of dl-(15R)-15 methyl-PGE2 methyl ester (PG6E), in experimental ulcers induced by absolute alcohol, HCl, indomethacin, pyloric ligation and chronic acetic acid in rats were studied. PG6E at doses 10-80 micrograms.kg-1 was shown to have significant protective effect. PG6E (30-60 micrograms.kg-1) was also found to reduce markedly the acid secretion, pepsin activity, DNA content of the juice collected from pylorus ligated stomach of rats and increase markedly the content of gastric mucosa hexosamine in mice given PG6E (30-60 micrograms.kg-1 po for 3 d). At doses of 40-80 micrograms.kg-1, PG6E was able to have no significant effect on gastric emptying time in rats and gastrointestinal tract movement in mice. It appears that PG6E was shown to inhibit the aggressive factors and increase the protective factors of gastric mucosa. This may hopefully become a new antiulcer agent.