Search

In the context of 2+1 dimensional Dirac materials, we consider electromagnetic interactions alongside a type of spin-dependent Hubbard interaction. The former is described by PQED theory, while the latter corresponds to an effective theory represented by the $SU(N_c)$ Thirring model. Employing Hubbard-Stratonovich transformation and large N expansion in the model yields a non-local $SU(N_c)$ Yang-Mills action. Subsequently, we solve Schwinger-Dyson equations to obtain the self-energy function of the fermion propagator, from which we determine the critical fermion flavor number $N^c_f$ and critical fine structure constant $\alpha_c$ indicative of chiral symmetry breaking. Our findings suggest that as the non-Abelian color number $N_c$ increases, the minimum value of the critical fermion flavor number monotonically increases, while the maximum value of the critical fine structure constant decreases accordingly, rendering the system more susceptible to chiral symmetry breaking., Comment: 9 pages, 4 figures

Induction of hypothermia during hibernation/torpor enables certain mammals to survive under extreme environmental conditions. However, pharmacological induction of hypothermia in most mammals remains a huge challenge. Here we show that a natural product P57 promptly induces hypothermia and decreases energy expenditure in mice. Mechanistically, P57 inhibits the kinase activity of pyridoxal kinase (PDXK), a key metabolic enzyme of vitamin B6 catalyzing phosphorylation of pyridoxal (PL), resulting in the accumulation of PL in hypothalamus to cause hypothermia. The hypothermia induced by P57 is significantly blunted in the mice with knockout of PDXK in the preoptic area (POA) of hypothalamus. We further found that P57 and PL have consistent effects on gene expression regulation in hypothalamus, and they may activate medial preoptic area (MPA) neurons in POA to induce hypothermia. Taken together, our findings demonstrate that P57 has a potential application in therapeutic hypothermia through regulation of vitamin B6 metabolism and PDXK serves as a previously unknown target of P57 in thermoregulation. In addition, P57 may serve as a chemical probe for exploring the neuron circuitry related to hypothermia state in mice.

Feng-jia Chen,1,2,* Li-juan Du,1,2,* Zhimin Zeng,1,2,* Xin-yan Huang,1,2 Chang-yi Xu,1,2 Wei-ping Tan,1,2 Can-mao Xie,1,2 Yu-xia Liang,1,2 Yu-biao Guo1,2 1Division of Pulmonary and Critical Care Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, People’s Republic of China; 2Institute of Pulmonary Diseases, Sun Yat-sen University, Guangzhou, Guangdong, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yu-biao Guo; Yu-xia Liang, Tel +86 20 8775 5766, Email guoyb@mail.sysu.edu.cn; liangyx69@mail.sysu.edu.cnPurpose: PTPRH inhibits EGFR activity directly in cancer patients and activated EGFR induces goblet cell hyperplasia and mucus hypersecretion in asthma. However, the function of PTPRH in asthma remains unknown. The purpose of this study was to access the association of PTPRH with asthma and its underlying mechanism.Patients and Methods: We examined the PTPRH level in asthma patients (n = 108) and healthy controls (n = 35), and analyzed the correlations between PTPRH and asthma-related indicators. Human bronchial epithelial cell (HBECs) transfected with PTPRH and asthma mouse model were set up to investigate the function of PTPRH.Results: The expression of PTPRH was significantly increased and correlated with pulmonary function parameters, including airway obstruction, and T-helper2 (Th2) associated markers in asthma patients. PTPRH increased in the house dust mite (HDM)-induced asthmatic mice, while Th2 airway inflammation and Muc5ac suppressed when treated with PTPRH. Accordingly, PTPRH expression was markedly increased in IL-13-stimulated HBECs but PTPRH over-expression suppressed MUC5AC. Moreover, HBECs transfected with over-expressed PTPRH inhibited the phosphorylation of EGFR, ERK1/2 and AKT, while induced against PTPRH in HBECs dephosphorylated of EGFR, ERK1/2 and AKT.Conclusion: PTPRH reduces MUC5AC secretion to alleviate airway obstruction in asthm

Feng-jia Chen,1,2,* Li-juan Du,1,2,* Zhimin Zeng,1,2,* Xin-yan Huang,1,2 Chang-yi Xu,1,2 Wei-ping Tan,1,2 Can-mao Xie,1,2 Yu-xia Liang,1,2 Yu-biao Guo1,2 1Division of Pulmonary and Critical Care Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, People’s Republic of China; 2Institute of Pulmonary Diseases, Sun Yat-sen University, Guangzhou, Guangdong, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yu-biao Guo; Yu-xia Liang, Tel +86 20 8775 5766, Email guoyb@mail.sysu.edu.cn; liangyx69@mail.sysu.edu.cnPurpose: PTPRH inhibits EGFR activity directly in cancer patients and activated EGFR induces goblet cell hyperplasia and mucus hypersecretion in asthma. However, the function of PTPRH in asthma remains unknown. The purpose of this study was to access the association of PTPRH with asthma and its underlying mechanism.Patients and Methods: We examined the PTPRH level in asthma patients (n = 108) and healthy controls (n = 35), and analyzed the correlations between PTPRH and asthma-related indicators. Human bronchial epithelial cell (HBECs) transfected with PTPRH and asthma mouse model were set up to investigate the function of PTPRH.Results: The expression of PTPRH was significantly increased and correlated with pulmonary function parameters, including airway obstruction, and T-helper2 (Th2) associated markers in asthma patients. PTPRH increased in the house dust mite (HDM)-induced asthmatic mice, while Th2 airway inflammation and Muc5ac suppressed when treated with PTPRH. Accordingly, PTPRH expression was markedly increased in IL-13-stimulated HBECs but PTPRH over-expression suppressed MUC5AC. Moreover, HBECs transfected with over-expressed PTPRH inhibited the phosphorylation of EGFR, ERK1/2 and AKT, while induced against PTPRH in HBECs dephosphorylated of EGFR, ERK1/2 and AKT.Conclusion: PTPRH reduces MUC5AC secretion to alleviate airway obstruction in asthm

It is a crucial step to achieve effective semantic segmentation of lane marking during the construction of the lane level high-precision map. In recent years, many image semantic segmentation methods have been proposed. These methods mainly focus on the image from camera, due to the limitation of the sensor itself, the accurate three-dimensional spatial position of the lane marking cannot be obtained, so the demand for the lane level high-precision map construction cannot be met. This paper proposes a lane marking semantic segmentation method based on LIDAR and camera fusion deep neural network. Different from other methods, in order to obtain accurate position information of the segmentation results, the semantic segmentation object of this paper is a bird's eye view converted from a LIDAR points cloud instead of an image captured by a camera. This method first uses the deeplabv3+ [\ref{ref:1}] network to segment the image captured by the camera, and the segmentation result is merged with the point clouds collected by the LIDAR as the input of the proposed network. In this neural network, we also add a long short-term memory (LSTM) structure to assist the network for semantic segmentation of lane markings by using the the time series information. The experiments on more than 14,000 image datasets which we have manually labeled and expanded have shown the proposed method has better performance on the semantic segmentation of the points cloud bird's eye view. Therefore, the automation of high-precision map construction can be significantly improved. Our code is available at https://github.com/rolandying/FusionLane.

Ground segmentation is an important preprocessing task for autonomous vehicles (AVs) with 3D LiDARs. To solve the problem of existing ground segmentation methods being very difficult to balance accuracy and computational complexity, a fast point cloud ground segmentation approach based on a coarse-to-fine Markov random field (MRF) method is proposed. The method uses an improved elevation map for ground coarse segmentation, and then uses spatiotemporal adjacent points to optimize the segmentation results. The processed point cloud is classified into high-confidence obstacle points, ground points, and unknown classification points to initialize an MRF model. The graph cut method is then used to solve the model to achieve fine segmentation. Experiments on datasets showed that our method improves on other algorithms in terms of ground segmentation accuracy and is faster than other graph-based algorithms, which require only a single core of an I7-3770 CPU to process a frame of Velodyne HDL-64E data (in 39.77 ms, on average). Field tests were also conducted to demonstrate the effectiveness of the proposed method., Comment: 16 page,22 figures

With the development of intelligent vehicle systems, a high-precision road map is increasingly needed in many aspects. The automatic lane lines extraction and modeling are the most essential steps for the generation of a precise lane-level road map. In this paper, an automatic lane-level road map generation system is proposed. To extract the road markings on the ground, the multi-region Otsu thresholding method is applied, which calculates the intensity value of laser data that maximizes the variance between background and road markings. The extracted road marking points are then projected to the raster image and clustered using a two-stage clustering algorithm. Lane lines are subsequently recognized from these clusters by the shape features of their minimum bounding rectangle. To ensure the storage efficiency of the map, the lane lines are approximated to cubic polynomial curves using a Bayesian estimation approach. The proposed lane-level road map generation system has been tested on urban and expressway conditions in Hefei, China. The experimental results on the datasets show that our method can achieve excellent extraction and clustering effect, and the fitted lines can reach a high position accuracy with an error of less than 10 cm, Comment: 7 pages

Qing Liu, Biao Yu, Yingbin Tian, Juhua Dan, Ying Luo, Xiaoming Wu Laboratory of Molecular Genetics of Aging & Tumor, Medical School, Kunming University of Science and Technology, Kunming, Yunnan 650500, People’s Republic of ChinaCorrespondence: Ying Luo; Xiaoming Wu Email yingluo@kust.edu.cn; xiao_tracy@kust.edu.cnBackground: Cancer-associated fibroblasts (CAFs) play important roles in cancer development and progression. Recent studies show that p53 plays a cell non-autonomous tumor-suppressive role to restrict tumor growth in CAFs. However, the role of p53 mutant in CAFs remains obscure.Methods: In this study, the contribution of p53 mutant p53N236S (p53S) to CAFs activation was examined using mouse embryonic fibroblasts (MEFs) from wild-type (WT), p53 deficient (p53-/-) and p53S/S mice. The role of p53S in MEFs in inducing prostate cancer cell growth and metastasis was studied by utilizing xenograft models and transwell assays. The effects of p53S on the properties of CAFs were assessed by measuring CAFs-specific factors expression and functional collagen contraction assay. Moreover, Microarray data were analyzed by GSEA and Stat3 signaling was inhibited to further determine p53S’s role in the CAFs activation.Results: We found that p53S/S MEF accelerated cancer cells growth and metastasis compared with WT and p53-/- MEF. We also found that p53S induced significantly increasing collagen contraction in fibroblasts and overexpression of CAFs-specific factors, such as α-smooth muscle actin (α-SMA), FGF10 and CXCL12. p53S regulated these CAF-specific properties through Stat3 activation.Conclusion: Our results illustrate that p53S plays an important role in CAFs activation by the Stat3 pathway. The study indicates that cancer cells and fibroblasts interaction promotes prostate cancer cell growth, migration and invasion due to p53S expression in fibroblasts.Keywords: p53N236S, cancer-associated fibroblasts, Stat3 pathway

Feng-jia Chen,* Geng-peng Lin,* Xin-yan Huang, Yang-li Liu, Zhi-min Zeng, Yu-biao Guo Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yu-biao GuoDepartment of Pulmonary and Critical Care Medicine, The First Affiliated Hospital of Sun Yat-Sen University, Institute of Respiratory Diseases of Sun Yat-Sen University, No. 58 Zhongshan 2nd Road, Guangzhou 510080, Guangdong, People’s Republic of ChinaTel +86 20 8775 5766Email huxineikegyb@163.comBackground: Biotherapy for asthma may be useful in patients suffering from chronic obstructive pulmonary disease (COPD) with asthma characteristics. Therefore, the evaluation and close monitoring of asthma characteristics in severe and extremely severe COPD can guide treatment decisions to improve prognosis.Methods: Stable patients suffering from COPD and having a forced expiratory volume in 1 s (FEV1%) of ≤50% (GOLD 3–4) in the First Affiliated Hospital of Sun Yat-Sen University from December 2014 to June 2018 were retrospectively enrolled in this study and evaluated in terms of their asthma characteristics (blood eosinophil counts, fractional exhaled NO [FeNO] values, and reversibility).Results: A total of 178 patients with an average age of 65.62±9.28 years were enrolled in this study. A total of 85 patients had an improvement of ≥12% in FEV1%, and 61 of these patients had an absolute increase of >200 mL. Of 122 patients, 68 had blood eosinophil counts of ≥150 cells/μl, whereas 27 showed blood eosinophil counts ≥300 cells/μl. The blood eosinophil of ≥2% was found in 66/122 (54.10%) patients, whereas ≥3% was found in 51/122 (41.80%) patients. A total of 46 of 58 patients had an increased serum IgE level of ≥30 IU/mL, and 32 patients had an IgE of ≥100 IU/mL.

The ss-(1 -> 2)-linked 6-deoxy-L-altropyranose di- to pentasaccharides 2-5, relevant to the O-antigen of the infectious Yersinia enterocolitica 0:3, were synthesized for the first time. The challenging 1,2-cis-altropyranosyl linkage was assembled effectively via glycosylation with 2-O-benzyl-3,4-di-O-benzoyl-6-deoxy-L-altropyranosyl ortho-hexynylbenzoate (7) under the catalysis of PPh3AuNTf2. NMR and molecular modeling studies showed that the pentasaccharide (5) adopted a left-handed helical conformation. [GRAPHICS]

The ss-(1 -> 2)-linked 6-deoxy-L-altropyranose di- to pentasaccharides 2-5, relevant to the O-antigen of the infectious Yersinia enterocolitica 0:3, were synthesized for the first time. The challenging 1,2-cis-altropyranosyl linkage was assembled effectively via glycosylation with 2-O-benzyl-3,4-di-O-benzoyl-6-deoxy-L-altropyranosyl ortho-hexynylbenzoate (7) under the catalysis of PPh3AuNTf2. NMR and molecular modeling studies showed that the pentasaccharide (5) adopted a left-handed helical conformation. [GRAPHICS]

The ss-(1 -> 2)-linked 6-deoxy-L-altropyranose di- to pentasaccharides 2-5, relevant to the O-antigen of the infectious Yersinia enterocolitica 0:3, were synthesized for the first time. The challenging 1,2-cis-altropyranosyl linkage was assembled effectively via glycosylation with 2-O-benzyl-3,4-di-O-benzoyl-6-deoxy-L-altropyranosyl ortho-hexynylbenzoate (7) under the catalysis of PPh3AuNTf2. NMR and molecular modeling studies showed that the pentasaccharide (5) adopted a left-handed helical conformation. [GRAPHICS]

The ss-(1 -> 2)-linked 6-deoxy-L-altropyranose di- to pentasaccharides 2-5, relevant to the O-antigen of the infectious Yersinia enterocolitica 0:3, were synthesized for the first time. The challenging 1,2-cis-altropyranosyl linkage was assembled effectively via glycosylation with 2-O-benzyl-3,4-di-O-benzoyl-6-deoxy-L-altropyranosyl ortho-hexynylbenzoate (7) under the catalysis of PPh3AuNTf2. NMR and molecular modeling studies showed that the pentasaccharide (5) adopted a left-handed helical conformation. [GRAPHICS]

Organically modified bentonite was prepared by using hexadecyl trimethyl ammonium bromide (HDTMA) under ultrasonic conditions in this experiment. The modified bentonite was used to treat the acid brilliant scarlet GR and the adsorption behavior was investigated. The results indicated that the adsorption isotherm data were well fit for the Langmuir isotherm model and the pseudo two-order adsorption kinetics equation has the highest goodness of fit and the best linear correlation. © (2012) Trans Tech Publications, Switzerland.

Organically modified bentonite was prepared by using hexadecyl trimethyl ammonium bromide (HDTMA) under ultrasonic conditions in this experiment. The modified bentonite was used to treat the acid brilliant scarlet GR and the adsorption behavior was investigated. The results indicated that the adsorption isotherm data were well fit for the Langmuir isotherm model and the pseudo two-order adsorption kinetics equation has the highest goodness of fit and the best linear correlation. © (2012) Trans Tech Publications, Switzerland.

Organically modified bentonite was prepared by using hexadecyl trimethyl ammonium bromide (HDTMA) under ultrasonic conditions in this experiment. The modified bentonite was used to treat the acid brilliant scarlet GR and the adsorption behavior was investigated. The results indicated that the adsorption isotherm data were well fit for the Langmuir isotherm model and the pseudo two-order adsorption kinetics equation has the highest goodness of fit and the best linear correlation. © (2012) Trans Tech Publications, Switzerland.

There were five new diterpenoids, 18-beta-D-3,4 -diacetoxyxylopyranosyl-ent-kaur-16-ene (1), 18-beta-L-3,5 -diacetoxyarabinofuranosyl-ent-kaur-16-ene (2), 18-beta-D-3,6 -diacetoxyglucopyranosyl-ent-kaur-16-ene (3), ent-isopimar-8(14),15-dien-19-oic acid (4), and 5 alpha-hydroxy-ent-rosa-15-en-18-oic acid (5), isolated from the whole herb of Sagittaria pygmaea. Their structures and relative configurations were established based on spectroscopic studies, chemical methods, and X-ray crystallographic analysis. Compound 2 exhibited significant antibacterial activity against the oral pathogens, Streptococcus mutans ATCC 25175 and Actinomyces viscosus ATCC 27 044, with MIC values against both pathogens of 15.6 mu g/mL. Compound 3 was active against only A. viscosus ATCC 27044 with an MIC value of 62.5 mu g/mL. Compounds 4 and 5 were active against S. mutans ATCC 25175 and A. viscosus ATCC 27044, with MIC values against both pathogens of 125.0 mu g/mL.

There were five new diterpenoids, 18-beta-D-3,4 -diacetoxyxylopyranosyl-ent-kaur-16-ene (1), 18-beta-L-3,5 -diacetoxyarabinofuranosyl-ent-kaur-16-ene (2), 18-beta-D-3,6 -diacetoxyglucopyranosyl-ent-kaur-16-ene (3), ent-isopimar-8(14),15-dien-19-oic acid (4), and 5 alpha-hydroxy-ent-rosa-15-en-18-oic acid (5), isolated from the whole herb of Sagittaria pygmaea. Their structures and relative configurations were established based on spectroscopic studies, chemical methods, and X-ray crystallographic analysis. Compound 2 exhibited significant antibacterial activity against the oral pathogens, Streptococcus mutans ATCC 25175 and Actinomyces viscosus ATCC 27 044, with MIC values against both pathogens of 15.6 mu g/mL. Compound 3 was active against only A. viscosus ATCC 27044 with an MIC value of 62.5 mu g/mL. Compounds 4 and 5 were active against S. mutans ATCC 25175 and A. viscosus ATCC 27044, with MIC values against both pathogens of 125.0 mu g/mL.

There were five new diterpenoids, 18-beta-D-3,4 -diacetoxyxylopyranosyl-ent-kaur-16-ene (1), 18-beta-L-3,5 -diacetoxyarabinofuranosyl-ent-kaur-16-ene (2), 18-beta-D-3,6 -diacetoxyglucopyranosyl-ent-kaur-16-ene (3), ent-isopimar-8(14),15-dien-19-oic acid (4), and 5 alpha-hydroxy-ent-rosa-15-en-18-oic acid (5), isolated from the whole herb of Sagittaria pygmaea. Their structures and relative configurations were established based on spectroscopic studies, chemical methods, and X-ray crystallographic analysis. Compound 2 exhibited significant antibacterial activity against the oral pathogens, Streptococcus mutans ATCC 25175 and Actinomyces viscosus ATCC 27 044, with MIC values against both pathogens of 15.6 mu g/mL. Compound 3 was active against only A. viscosus ATCC 27044 with an MIC value of 62.5 mu g/mL. Compounds 4 and 5 were active against S. mutans ATCC 25175 and A. viscosus ATCC 27044, with MIC values against both pathogens of 125.0 mu g/mL.

alpha-l-Threofuranosyl nucleoside triphosphates (tNTPs) are tetrafuranose nucleoside derivatives and potential progenitors of present-day beta-d-2'-deoxyribofuranosyl nucleoside triphosphates (dNTPs). Therminator DNA polymerase, a variant of the 9 degrees N DNA polymerase, is an efficient DNA-directed threosyl nucleic acid (TNA) polymerase. Here we report a detailed kinetic comparison of Therminator-catalyzed TNA and DNA syntheses. We examined the rate of single-nucleotide incorporation for all four tNTPs and dNTPs from a DNA primer-template complex and carried out parallel experiments with a chimeric DNA-TNA primer-DNA template containing five TNA residues at the primer 3'-terminus. Remarkably, no drop in the rate of TNA incorporation was observed in comparing the DNA-TNA primer to the all-DNA primer, suggesting that few primer-enzyme contacts are lost with a TNA primer. Moreover, comparison of the catalytic efficiency of TNA synthesis relative to DNA synthesis at the downstream positions reveals a difference of no greater than 5-fold in favor of the natural DNA substrate. This disparity becomes negligible when the TNA synthesis reaction mixture is supplemented with 1.25 mM MnCl(2). These results indicate that Therminator DNA polymerase can recognize both a TNA primer and tNTP substrates and is an effective catalyst of TNA polymerization despite changes in the geometry of the reactants.

alpha-l-Threofuranosyl nucleoside triphosphates (tNTPs) are tetrafuranose nucleoside derivatives and potential progenitors of present-day beta-d-2'-deoxyribofuranosyl nucleoside triphosphates (dNTPs). Therminator DNA polymerase, a variant of the 9 degrees N DNA polymerase, is an efficient DNA-directed threosyl nucleic acid (TNA) polymerase. Here we report a detailed kinetic comparison of Therminator-catalyzed TNA and DNA syntheses. We examined the rate of single-nucleotide incorporation for all four tNTPs and dNTPs from a DNA primer-template complex and carried out parallel experiments with a chimeric DNA-TNA primer-DNA template containing five TNA residues at the primer 3'-terminus. Remarkably, no drop in the rate of TNA incorporation was observed in comparing the DNA-TNA primer to the all-DNA primer, suggesting that few primer-enzyme contacts are lost with a TNA primer. Moreover, comparison of the catalytic efficiency of TNA synthesis relative to DNA synthesis at the downstream positions reveals a difference of no greater than 5-fold in favor of the natural DNA substrate. This disparity becomes negligible when the TNA synthesis reaction mixture is supplemented with 1.25 mM MnCl(2). These results indicate that Therminator DNA polymerase can recognize both a TNA primer and tNTP substrates and is an effective catalyst of TNA polymerization despite changes in the geometry of the reactants.