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Synthesis and Anti-hepatitis B Virus Activities of Nitric Oxide-Releasing Derivatives of Matijin-Su

Guangping Liang, Peixue Cao, Xiuxia Yang, Zhengming Huang, Qingchuan Liu, Guangyi Liang, Bixue Xu
2014 Youji huaxue  
HepG2 2.2.15 细胞为乙肝病 毒载体, 对合成的马蹄金素衍生物进行了抗乙肝病毒活性测试. 结果表明, 在测试浓度范围内, 化合物 6d, 6e, 6g 具有 抗 HBV 活性, 其半数抑制浓度分别为 6.88, 37.51, 11.07 μmol/L. 其中, 化合物 6d 和 6g 的半数抑制浓度优于 MTS (11.16 μmol/L), 且具有较高的抑制率, 具有进一步研究开发的价值. Abstract By using N-(N-benzoyl-L-phenylalanyl)-O-acetyl-L-phenylalanol, named Matijin-Su, as a lead compound, a series of nitric oxide-releasing derivatives of Matijin-Su were synthesized and evaluated for their anti-hepatitis B virus activities in HepG2 2.2.15 cells. Compounds 6d, 6e and 6g
more » ... bited significant anti-HBV activities. The 50% inhibitory concentrations of these compounds towards HepG2 2.2.15 cells were 6.88, 37.51 and 11.07 μmol/L. Compounds 6d and 6g were less than Matijin-Su (IC 50 : 11.16 μmol/L). Compound 6d has potent in vitro anti-HBV activity, and could be worth of further research.
doi:10.6023/cjoc201312003 fatcat:mamo4qu7pbe4phovfmhg5e34za

Analysis of t-test misuses and SPSS operations in medical research papers

Guangping Liang, Wenliang Fu, Kaifa Wang
2019 Burns & Trauma  
In medical research papers, the selection of appropriate statistical methods serves as one of the pivotal premises to ensure the quality of papers and credibility of their results [1] [2] [3] . To correctly perform the statistical analysis of quantitative data, two key points should be considered. One is to identify the type of experimental design correctly, and the other is to check whether data meets the preconditions of parameter test [2] [3] [4] . Otherwise, it may cause different misuse in
more » ... some situations and may even draw different or opposite conclusions about the same data. As one of the most commonly used statistical methods in medical research papers, t-test can be divided into one-sample t-test and two-sample t-test [3, 4] . Thus, it is inappropriate to compare the means among multiple groups (more than three). Concretely, one-sample t-test is used to compare one group's average value to a single number (a known population mean, for example, the norm). The two-sample ttest is a type of inferential statistic used to determine if there is a significant difference between the means of two groups. Furthermore, there are two types of two-sample t-test [3, 4] . One is independent sample t-test (group t-test), which is performed when the samples typically consist of independent population. The other is paired (or correlated) sample t-test, which is used when each observation in one group is paired with a related observation in the other group, i.e., the samples typically consist of matched pairs of similar units, or when there are cases of repeated measures. Note that t-test belongs to the category of parametric test. The assumptions of the parametric test, including independence, normality, and homogeneity of variance, must be met to ensure the correct use of t-test [3, 4] . In addition, according to the theoretical deduction of t-test, it can only be applied to the quantitative data of single factor design, so it is inappropriate to perform t-test for multifactor design. For example, there are multiple independent variables/factors (such as gender and different types and dosage of drugs) and the comparisons among groups after controlling for simple effects of each independent variable. As a journal editor and reviewer, we often encounter that some authors blindly use t-test to process quantitative data without analyzing the prerequisites of t-test or considering the type of experimental design, especially to independent sample t-test (group t-test). In order to improve the quality of statistical analysis in medical research papers, according to the problems found in the process of reviewing manuscripts, we summarized the following five most common misuses of t-test and analyzed them with examples. We hope that it can provide real help to improve our data analysis ability. It is particularly noted that all the examples herein are artificially constructed for the purpose of illustration and do not represent actual clinical design and data. They are only for reference in the selection of statistical analysis methods.
doi:10.1186/s41038-019-0170-3 pmid:31720300 pmcid:PMC6839191 fatcat:b5yjyxjopjeffhbxnrpjc5l6j4

Gas transport in vertically-aligned carbon nanotube/parylene composite membranes

Lei Zhang, Bin Zhao, Xianying Wang, Youxuan Liang, Hanxun Qiu, Guangping Zheng, Junhe Yang
2014 Carbon  
A B S T R A C T Vertically-aligned carbon nanotube (VACNT) composite membranes were fabricated by impregnating carbon nanotube (CNT) forests with poly-para-xylylene (parylene-C) through room-temperature chemical vapor deposition (CVD). Transport properties of diverse gases through the CNT/parylene membranes were investigated. The gas permeances scaled inversely with their molecular weights in accordance with Knudsen model and the value of permeance was about 30 times higher than that predicted
more » ... y the Knudsen diffusion kinetics, which was attributed to the atomically smooth interiors of CNTs. In addition, the gas permeance values in this work were higher than those reported for other VACNT membranes, due to the smaller membrane thickness and good crystallinity of the CNTs. (J. Yang). C A R B O N 6 6 ( 2 0 1 4 ) 1 1 -1 7 A v ai l abl e a t w w w . s c i e n c e d i r e c t. c o m ScienceDirect j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / c a r b o n
doi:10.1016/j.carbon.2013.08.007 fatcat:eqnn2ygnc5celiit3o2dgo7zdu

Synthesis and Anti-hepatitis B Virus Activities of Matijin-Su Derivatives with Potential for Hepatic Targeting

Jie Yuan, Qingchuan Liu, Guangcan Xu, Zhanxing Hu, Guangping Liang, Zhengming Huang, Changxiao Liu, Guangyi Liang, Bixue Xu
2015 Youji huaxue  
To improve the concentration in liver lesion tissue and increase the anti-hepatitis B virus (HBV) activity of Matijin-Su [N-(N-benzoyl-L-phenylalanyl)-O-acetyl-L-phenylalanol, MTS] derivatives, five galactosyl derivatives of MTS with potential for hepatic targeting were synthesized and their structures were confirmed by 1 H NMR, 13 C NMR, 1 H-1 H COSY, HMQC and ESI-MS. The anti-HBV activities of those compounds were evaluated in HepG2 2.2.15 cells. The screening results showed that all target
more » ... mpounds had inhibitory effect on HBV DNA replication in HepG2 2.2.15 cells in a dose-effect relationship.
doi:10.6023/cjoc201505011 fatcat:pqoha44ptbdefcokc5cwkk6chu

Research on the Cross Section Forming Quality of Three-Dimensional Multipoint Stretch Forming Parts

Jiaqi Yu, Yi Li, Fei Teng, Jicai Liang, Xiangfeng Lin, Ce Liang, Guangyi Chen, Guangping Sun
2018 Advances in Materials Science and Engineering  
This paper introduced the basic principle and main influencing factors of the three-dimensional multipoint stretch forming process and investigated the optimized scheme of the cross section forming quality. The main factors affecting the stretch forming process were studied by the orthogonal test through the numerical simulation technique. In the case of a good target shape, the best combination of forming parameters was established by using the range method. The cross-sectional distortion of
more » ... e formed profile is the smallest when the prestretching amount is 1% of the profile length, the poststretching amount is 0.8% of the profile length, the number of the die heads is 12, and the friction coefficient is 0.15. The optimal combination of forming parameters was verified by the multipoint bending test.
doi:10.1155/2018/4265617 fatcat:wemym74bubftxmbcdsuivdhrce

Skin γδ T Cells and Their Function in Wound Healing

Wengang Hu, Ruoyu Shang, Jiacai Yang, Cheng Chen, Zhihui Liu, Guangping Liang, Weifeng He, Gaoxing Luo
2022 Frontiers in Immunology  
For the skin immune system, γδ T cells are important components, which help in defensing against damage and infection of skin. Compared to the conventional αβ T cells, γδ T cells have their own differentiation, development and activation characteristics. In adult mice, dendritic epidermal T cells (DETCs), Vγ4 and Vγ6 γδ T cells are the main subsets of skin, the coordination and interaction among them play a crucial role in wound repair. To get a clear overview of γδ T cells, this review
more » ... es their derivation, development, colonization and activation, and focuses their function in acute and chronic wound healing, as well as the underlining mechanism. The aim of this paper is to provide cues for the study of human epidermal γδ T cells and the potential treatment for skin rehabilitation.
doi:10.3389/fimmu.2022.875076 pmid:35479079 pmcid:PMC9035842 fatcat:277h6tmfarajjogyxuiphzj7qu

Apocynin attenuates left ventricular remodeling in diabetic rabbits

Jiuchun Qiu, Jianping Zhao, Jian Li, Xue Liang, Yajuan Yang, Zhiwei Zhang, Xiaowei Zhang, Huaying Fu, Panagiotis Korantzopoulos, Gary Tse, Tong Liu, Guangping Li
2017 OncoTarget  
Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases are responsible for the generation of reactive oxygen species, producing vascular and myocardial dysfunction in diabetes mellitus. However, the potential benefits of the NADPH oxidase inhibitor, apocynin, on left ventricular (LV) remodeling remain unknown. Results: In the diabetic group, interventricular septal thickness and left ventricular posterior wall thickness were markedly increased compared to control. These changes were
more » ... anied by increased LV cardiomyocyte cross-sectional area and greater degree of interstitial fibrosis. NO, myeloperoxidase, and malonaldehyde levels in the serum were significantly increased Moreover, protein expression levels of rac1, nuclear factor-κB, transforming growth factor-β, p38, P-p38, and metalloproteinase-9 were also raised. Apocynin treatment prevented all of these structural, histological and biochemical changes and additionally increased superoxide dismutase levels. Methods: Thirty Japanese rabbits were randomized into three groups: control, alloxan-induced diabetes with and without apocynin treatment at 15 mg/kg/day for 8 weeks (n = 10 for each group). Echocardiography was performed and hemodynamics were assessed by carotid and LV catheterization. LV cardiomyocyte cross-sectional area and interstitial fibrosis were evaluated by histology. Serum nitric oxide (NO), malonaldehyde, myeloperoxidase, superoxide dismutase (SOD) levels, and activity of LV tissue NADPH oxidases was assessed. Expression of proteins involved in proinflammatory and pro-fibrotic signaling were determined by Western blotting. Conclusions: Inhibition of NADPH oxidase using apocynin is an effective upstream therapy for preventing diabetes-induced adverse remodeling of the left ventricular myocardium.
doi:10.18632/oncotarget.16599 pmid:28388570 pmcid:PMC5503547 fatcat:bgul3cr6dna45kmu5fookzilfy

Reactive oxygen species mediated oxidative stress links diabetes and atrial fibrillation

Xue Liang, Qitong Zhang, Xinghua Wang, Meng Yuan, Yue Zhang, Zhao Xu, Guangping Li, Tong Liu
2018 Molecular Medicine Reports  
Diabetes is an independent risk factor for atrial fibrillation (AF); however, the underlying mechanism linking diabetes and AF remains to be clarified. The present study aimed to explore the molecular mechanism of increased reactive oxygen species (ROS) production in AF and the ROS-mediated downstream events in diabetes. Firstly, the atrial fibroblasts were isolated from the left atrium of rabbits using enzyme digestion and differential adhesion. Then, the isolated cells were identified by
more » ... ology analysis under a microscope, collagen distribution using Masson trichrome staining and vimentin by immunofluorescence. Following this, the collected atrial fibroblasts were randomly divided into 7 groups and administered with high glucose (25 mM glucose), H 2 O 2 stimulation (100 nmol/l), glucose + apocynin (100 µg/ml), H 2 O 2 + apocynin, glucose + H 2 O 2 , and a combination of glucose, apocynin and H 2 O 2 , as well as the negative control (NC). An MTS assay was performed to investigate cell proliferation following the different treatments, and western blotting was conducted to explore the expression of several proteins including NAD(P)H oxidative (NOX) subunits, key factors involved in mitogen-activated protein kinase (MAPK) signaling pathways and matrix metalloproteinases (MMPs). The atrial fibroblasts were spindle-shaped with one or more protuberances. Vimentin was positively expressed in collected cells under confocal laser scanning microscopy. This result indicated that the atrial fibroblasts were successfully prepared. High glucose and H 2 O 2 stimulation significantly increased the proliferation of atrial fibroblasts and apocynin markedly attenuated the promoting effects on cell proliferation induced by high glucose and H 2 O 2 treatment (P<0.05). Additionally, high glucose and H 2 O 2 stimulation increased the expression of Rac1, phospho(p)-c-Jun N-terminal kinase 1, p38, p-p38 and MMP9, which was markedly decreased by the addition of apocynin (P<0.05). The mechanism associated with diabetes and AF may be attributed to oxidative stress (ROS production) derived from NOX activity, and then induced activation of the MAPK signaling pathways and MMP9 expression.
doi:10.3892/mmr.2018.8472 pmid:29393403 pmcid:PMC5865952 fatcat:okjo5x3xxvh3vomvyam5qykdd4

Overexpression of MicroRNA-16 Alleviates Atherosclerosis by Inhibition of Inflammatory Pathways

Manman Wang, Jiao Li, Jiageng Cai, Lijun Cheng, Xuewen Wang, Pengjuan Xu, Guangping Li, Xue Liang
2020 BioMed Research International  
Xue Liang and Guangping Li conceived and designed the study. Manman Wang, Jiao Li, and Jiageng Cai conducted the in vivo experiments.  ...  Manman Wang and Xue Liang wrote the manuscript. All authors read and approved the final manuscript. Manman Wang, Jiao Li and Jiageng Cai contributed equally to this work.  ... 
doi:10.1155/2020/8504238 pmid:32775445 pmcid:PMC7391121 fatcat:3o5tg6hkmraulb4eamraua6mj4

Dynamics and Switching Control of a Class of Underactuated Mechanical Systems with Variant Constraints

Tingting Su, Xu Liang, Guangping He, Taoming Jia, Quanliang Zhao, Lei Zhao
2019 Applied Sciences  
Locomotion systems with variant constraints are familiar in real world applications, but the dynamics and control issues of variant constraint systems have not been sufficiently discussed to date. From the viewpoint of Lagrange–d'Alembert equations with additional variable constraints, this paper investigates the modeling approaches of a class of hybrid dynamical systems (HDS) with instantaneously variant constraints and the switching control techniques of stabilizing the HDS to given periodic
more » ... rbits. It is shown that under certain conditions there possibly exist zero impact periodic orbits in the HDS, and the HDS can be stabilized to the period-one orbits by a linear controller with only partial state feedback, even though the HDS are generally underactuated nonholonomic systems. As an example, a one-legged planar hopping robot is employed to demonstrate the main results of modeling and control of a class of HDS.
doi:10.3390/app9204235 fatcat:hgm3royj2jepbhkqzjijjvywpm

Characteristics and Influencing Factors of Spatial Differentiation of Urban Black and Odorous Waters in China

Guolei Chen, Jing Luo, Chunyan Zhang, Liang Jiang, Lingling Tian, Guangping Chen
2018 Sustainability  
The pollution problem caused by urban black and odorous waters has received much attention from the Chinese government. Our research aims at systematically identifying the characteristics and the influential factors of spatial differentiation of urban black and odorous waters across China. The research, based on the data of black and odorous waters from 2100 Chinese cities, was conducted with the spatial analysis tool of ArcGIS. We found that the amount of Chinese urban black and odorous waters
more » ... varied in spatial distribution, which was an agglomerated type with significant agglomeration. The kernel density was characterized by independent single kernel centers with ribbon-like and sporadic distributions of subcenters. The cold and hot spots showed a gradient distribution pattern of cold in the southwest and hot in the central east. These spatial distribution characteristics could be attributed to the following core factors, total wastewater discharge, length of urban drainage pipelines, municipal solid waste collection, daily urban sewage treatment capacity, and investment in urban pollution treatment of wastewater. The findings reveal the current geospatial distribution of black and odorous waters pollution and provide reference for the Chinese government to treat the pollution from several key points. Lastly, it is suggested that the Chinese government should establish joint control, joint prevention, and joint treatment mechanisms in the black and odorous waters areas and improve the safety standards of the whole water environment, so as to promote the treatment and elimination of urban black and odorous waters.
doi:10.3390/su10124747 fatcat:g646o24rivdntpqaeckbqv6x7y

Improved diffusion imaging through SNR-enhancing joint reconstruction

Justin P. Haldar, Van J. Wedeen, Marzieh Nezamzadeh, Guangping Dai, Michael W. Weiner, Norbert Schuff, Zhi-Pei Liang
2012 Magnetic Resonance in Medicine  
Introduction -The EPI readouts used to acquire most diffusion weighted images (DWIs) are well known to produce localized geometric distortions in the presence of B0 field inhomogeneity. These artifacts, which manifest as local stretching or compression of the image along the phase encoding (PE) direction, are problematic when attempting to co-register diffusion images with other scans or attempting to estimate diffusion characteristics in highly-distorted regions. Geometric distortions can be
more » ... curately predicted from the B0 inhomogeneity map, and many methods use measured field maps to partially correct distortions [1]. However, these corrections are of limited use in image regions where the distortions have superposed signals from multiple different spatial locations. The reversedgradient (RG) method [2], in which images are acquired with two different PE orientations (PEOs), can overcome these effects at the expense of doubling the data acquisition time. This work proposes a novel acquisition and reconstruction strategy that leverages a constrained reconstruction formulation to enable accurate RG distortion correction from only half the amount of data required for the standard RG approach. Theory -Reversing the orientation of the PE gradient in EPI causes stretching artifacts to become compression artifacts, and vice versa. As illustrated in Fig. 1 , acquiring two PEOs enables better artifact correction than can be obtained from a single PEO. Compared to conventional RG, which acquires every image with two PEOs, we propose to reduce the scan time by acquiring half the images with one PEO and half with the other. Distortion correction of these images is then performed jointly, using a constrained reconstruction formulation that uses the prior knowledge that the diffusion signal in each voxel should be smooth in q-space. Materials and Methods -We assume a DWI acquisition with spherical q-space sampling, and choose PEOs for each DWI in an interleaved fashion (as shown in Fig. 2 , where white dots and black dots correspond to different PEOs). We use the acquired distorted diffusion images ( ) to estimate undistorted images ( ) by minimizing ∑ ∑ , ... , . . , where, subscripts and correspond to different diffusion encodings
doi:10.1002/mrm.24229 pmid:22392528 pmcid:PMC3407310 fatcat:o4kqcqx2kvgk7ma4dhxk3awl5e

Heparin Attenuates Histone-Mediated Cytotoxicity in Septic Acute Kidney Injury

Ziyi Wang, Lijun Wang, Chao Cao, Heng Jin, Yan Zhang, Yancun Liu, Yulei Gao, Xue Liang, Guangping Li, Songtao Shou
2020 Frontiers in Medicine  
ACKNOWLEDGMENTS The authors wish to acknowledge the technical assistance of Yue Zhang and Jian Li for animal handling procedures, Xing Liu for flow cytometry, Xue Liang, and QianKun Bao for western blotting  ... 
doi:10.3389/fmed.2020.586652 pmid:33344474 pmcid:PMC7738632 fatcat:4rskxgw5yze65cfju6zmzlqlnq

Investigation of highly expressed PCSK9 in atherosclerotic plaques and ox-LDL-induced endothelial cell apoptosis

Jiao Li, Xue Liang, Yuanyuan Wang, Zhao Xu, Guangping Li
2017 Molecular Medicine Reports  
The present study aimed to explore the direct toxicity of proprotein convertase subtilisin/kexin type 9 (PCSK9) to atherosclerosis (AS) and its association with apoptotic endothelial cells. Apolipoprotein E -/mice were randomly divided into two groups, control and experimental. The control group was administered a normal diet and the experimental group was administered a high-fat diet. After 20 weeks, the aorta was isolated and dissected. Hematoxylin and eosin staining, and immunohistochemical
more » ... nalysis were performed. Human umbilical vein endothelial cells were incubated with varied concentrations of oxidized low-density lipoprotein (ox-LDL) for different times. The apoptotic rate was detected by flow cytometry. Western blotting and reverse transcription-quantitative polymerase chain reaction analysis were conducted to detect the expression of PCSK9, B-cell lymphoma 2 (Bcl-2), bcl-2-like protein 4 (Bax) and caspase-3. Short hairpin (sh) RNA-PCSK9 was transfected into endothelial cells using lentiviral transfection. The expression levels of PCSK9, Bax, Bcl-2, caspase-3 and the mitogen-activated protein kinase (MAPK) pathway proteins were detected. The high-fat group was successfully established as an AS model and PCSK9 was highly expressed in the AS plaque. Treatment with ox-LDL induced apoptosis and increased mRNA and protein levels of PCSK9. PCSK9 mRNA and proteins levels were downregulated by shRNA-PCSK9. The deficiency of PCSK9 markedly inhibited the expression of pro-apoptotic proteins and promoted anti-apoptotic proteins. In addition, phosphorylation of p38 and c-Jun N-terminal kinases was altered by shRNA-PCSK9. Targeting of PCSK9 by shRNA-PCSK9 may repress endothelial cell apoptosis through MAPK signaling in AS, providing a novel direction for understanding the mechanism and treatment of AS.
doi:10.3892/mmr.2017.6803 pmid:28656218 pmcid:PMC5561783 fatcat:v7tkapoa5zdjxovjveth4hjwte

Circulating miRNA-21 as a diagnostic biomarker in elderly patients with type 2 cardiorenal syndrome

Yan Wang, Yi Liang, WenJun Zhao, GuangPing Fu, QingQuan Li, XuChen Min, YiFang Guo
2020 Scientific Reports  
Circulating miRNAs have attracted attention as serum biomarkers for several diseases. In this study, we aimed to evaluate the diagnostic value of circulating miRNA-21 (miR-21) as a novel biomarker for elderly patients with type 2 cardiorenal syndrome (CRS-2). A total of 157 elderly patients with chronic heart failure (CHF) were recruited for the study. According to an estimated glomerular filtration rate (eGFR) cut-off of 60 ml/min/1.73 m2, 84 patients (53.5%) and 73 patients (46.5%) were
more » ... ed to the CRS group and the CHF group, respectively. Expression levels of serum miR-21 and biomarkers for CRS, such as kidney injury factor-1 (KIM-1), neutrophil gelatinase-related apolipoprotein (NGAL), cystatin C (Cys C), amino-terminal pro-B-type natriuretic peptide (NT-proBNP), N-acetyl-κ-D-glucosaminidase (NAG), and heart-type fatty acid-binding protein (H-FABP), were detected. Serum miR-21, KIM-1, NGAL, Cys C, NT-proBNP and H-FABP levels were significantly higher in the CRS group than in the CHF group (P < 0.01), whereas NAG expression was not significantly different between the two groups (P > 0.05). Cys C, H-FABP and eGFR correlated significantly with miR-21 expression, but correlations with miR-21 were not significant for NT-proBNP, NGAL, NAG and KIM-1. Moreover, multivariate logistic regression found that serum miR-21, increased serum Cys C, serum KIM-1, hyperlipidaemia and ejection fraction (EF) were independent influencing factors for CRS (P < 0.05). The AUC of miR-21 based on the receiver operating characteristic (ROC) curve was 0.749, with a sensitivity of 55.95% and a specificity of 84.93%. Furthermore, combining miR-21 with Cys C enhanced the AUC to 0.902, with a sensitivity of 88.1% and a specificity of 83.6% (P < 0.001). Our findings suggest that circulating miR-21 has medium diagnostic value in CRS-2. The combined assessment of miR-21 and Cys C has good clinical value in elderly patients with CRS-2.
doi:10.1038/s41598-020-61836-z pmid:32184430 fatcat:pxjliepebfhotftq7cp5llcwwe
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