1.Effects of Coronary Artery Lesion Characteristics on Myocardial Ischemia
Xiaolu XI ; Bao LI ; Na LI ; Jincheng LIU ; Yili FENG ; Youjun LIU
Journal of Medical Biomechanics 2023;38(3):E458-E464
Objective To investigated the effect of stenosis characteristics (vascular elasticity and plaque properties) on myocardial ischemia. Methods An ideal geometric multi-scale coronary stenosis model based on fluid-structure interaction was established, and the fractional flow reserve (FFR) was simulated to evaluate myocardial ischemia. The effects of vascular elastic wall (elastic modulus of 1 MPa) and rigid wall, plaque types (lipid-rich plaque and calcified plaque) and plaque volume on myocardial ischemia were considered separately. Results The FFRCT simulation result of vessels with elastic wall was larger than that with rigid wall under all stenosis situations. The FFRCT of vessels in lipid-rich lesions was higher than that of calcified plaque (P=0.001). The trapezoidal plaque volume was larger than the cosine plaque volume, and the FFRCT of vessels in trapezoidal plaque was smaller than that of cosine plaque (P=0.001). Conclusions Vascular elasticity is a critical factor to simulate vascular hemodynamics. In moderate stenosis, calcified plaques are more likely to induce myocardial ischemia due to the larger luminal deformation and dilation of rich lipid plaque. When the stenosis is constant, the smaller the plaque volume, the higher the FFRCT and the smaller the possibility of myocardial ischemia.
2.Towards understanding antibiotic resistance in animals-borne bacterial pathogens.
Jian SUN ; Yahong LIU ; Youjun FENG
Chinese Journal of Biotechnology 2018;34(8):1246-1258
Antimicrobial resistance is a common problem in both veterinary and human medicine. The increasing incidence of multi-drug resistance and even pan-drug resistance is posing serious threat to public health and food safety. This review aimed to present an updated overview on antimicrobial resistance, covering the transmission mechanisms and its potential controlling strategies.
3. Transformation of endogenous reactive oxygen species participates into bacterial antibiotic resistance
Xin LI ; Yongliang ZHONG ; Youjun FENG
Chinese Journal of Preventive Medicine 2018;52(4):446-450
A growing body of diversified antibiotic resistances raises a significant challenge to anti-infection clinical therapeutics. The emergence of superbugs carrying MCR-1/2 or NDM-1 determinants underlines the importance and urgency in elucidation of molecular mechanisms shared by antibiotic resistances. It is aware that different classes of bactericidal antibiotics consistently stimulate the production of deleterious reactive oxygen species (ROS), which are accompanied with metabolic disturbance. The different destinations of ROS determine its consequence on bacterial fate. Here, we review antibiotic-induced production, progression and transformation of ROS, as well as its role in the development of antibiotic resistance. Additionally, we anticipate that mesosome-like structures-aided exclusion of hydrogen peroxide might represent a previously-unknown mechanism for antibiotic resistance. This mini-review is aiming to present an update overview on antibiotic resistance and provide clues to the development of novel antibiotics.
4.Transformation of endogenous reactive oxygen species participates into bacterial antibiotic resistance
Xin LI ; Yongliang ZHONG ; Youjun FENG
Chinese Journal of Preventive Medicine 2018;52(4):446-450
A growing body of diversified antibiotic resistances raises a significant challenge to anti-infection clinical therapeutics.The emergence of superbugs carrying MCR-1/2 or NDM-1 determinants underlines the importance and urgency in elucidation of molecular mechanisms shared by antibiotic resistances.It is aware that different classes of bactericidal antibiotics consistently stimulate the production of deleterious reactive oxygen species (ROS), which are accompanied with metabolic disturbance. The different destinations of ROS determine its consequence on bacterial fate. Here, we review antibiotic-induced production,progression and transformation of ROS,as well as its role in the development of antibiotic resistance. Additionally, we anticipate that mesosome-like structures-aided exclusion of hydrogen peroxide might represent a previously-unknown mechanism for antibiotic resistance. This mini-review is aiming to present an update overview on antibiotic resistance and provide clues to the development of novel antibiotics.
5.Transformation of endogenous reactive oxygen species participates into bacterial antibiotic resistance
Xin LI ; Yongliang ZHONG ; Youjun FENG
Chinese Journal of Preventive Medicine 2018;52(4):446-450
A growing body of diversified antibiotic resistances raises a significant challenge to anti-infection clinical therapeutics.The emergence of superbugs carrying MCR-1/2 or NDM-1 determinants underlines the importance and urgency in elucidation of molecular mechanisms shared by antibiotic resistances.It is aware that different classes of bactericidal antibiotics consistently stimulate the production of deleterious reactive oxygen species (ROS), which are accompanied with metabolic disturbance. The different destinations of ROS determine its consequence on bacterial fate. Here, we review antibiotic-induced production,progression and transformation of ROS,as well as its role in the development of antibiotic resistance. Additionally, we anticipate that mesosome-like structures-aided exclusion of hydrogen peroxide might represent a previously-unknown mechanism for antibiotic resistance. This mini-review is aiming to present an update overview on antibiotic resistance and provide clues to the development of novel antibiotics.
6.Value of T2WI scores in diagnosis and differential diagnosis of transition zone prostate cancer
Yongsheng ZHANG ; Feng CUI ; Zhitian ZHANG ; Youjun CAO ; Yinfeng MA ; Zaiqiu ZHAO ; Miao'er LI ;
Journal of Practical Radiology 2017;33(9):1386-1389
Objective To evaluate the value of T2WI scores for diagnosis and differential diagnosis of transition zone prostate cancer(PCa).Methods T2WI of 43 cases of transition zone PCa and 91 cases of benign prostatic hyperplasia(BPH) were analyzed retrospectively.Transition zone T2WI signs were divided into the main signs and the secondary signs, which were given different scores and were evaluated separately by receiver operating characteristic (ROC) curve for their diagnostic value.Results In a total of 11 scores sections (-1-10), as the increase of scores, the sensitivity of transition zone PCa was decreased while the specificity and positive predictive value were both increased.According to the ROC curve, when the critical value of scores≥4.5, the sensitivity, specificity, negative predictive value, and the accuracy were 81%,73.3%,90.9%,70.4% respectively.When the scores ≥8.5,the specificity and positive predictive value were both 100%.When the scores ≥0.5 and ≥1.5,the negative predictive value were 100%.Conclusion T2WI scores can quantitatively analyze the transition zone PCa,which has an important value to improve the clinical diagnosis and guide treatment.
7.Evaluation of multiparametric MRI in diagnosing early prostate cancer:a study based on PI-RADS version 2
Yongsheng ZHANG ; Huan YANG ; Youjun CAO ; Yinyu WANG ; Zhitian ZHANG ; Yinfeng MA ; Zaiqiu ZHAO ; Feng CUI
Journal of Practical Radiology 2017;33(7):1052-1055,1083
Objective To investigate the diagnostic value of multiparametric MRI in early prostate cancer(PCa) based on PI-RADS version 2.Methods 27 surgically-proved early PCa patients were collected in this retrospective study.T2WI,DWI and DCE were evaluated by two blinded radiologists.By 12 sub-region classification method the possibility of the presence of cancer at each sub-region was scored according to the PI-RADS V2.The receiver operating characteristic (ROC) curve was used to analyze the diagnosic efficacy of the following 4 protocols:T2WI alone(protocol 1),T2WI+DWI(protocol 2),T2WI+DCE(protocol 3),T2WI+DWI+DCE(protocol 4).The sensitivity,specificity and accuracy for each protocol were calculated.The average scores of cancerous sub-regions and non-cancerous sub-regions were calculated and the independent sample t test was used to compare the four protocols.Results 324 sub-regions were analyzed in 27 early PCa patients and then divided into 119 cancerous sub-regions and 205 non-cancerous sub-regions,including 64 peripheral zone cancerous sub-regions and transition zone cancerous sub-regions.In protocol 1-4, the average scores of cancerous sub-regions in orderwere 3.13±1.19,3.27±1.15,3.28±1.23, 3.33±1.16,respectively.Non-cancerous sub-regions's scores in order were 1.98±0.90,1.91±0.91, 2.03±0.99,1.94±0.96 respectively and there were significant differences among each protocol (P<0.05).The area under the ROC curve of the 4 protocols for region-based analysis were displayed in descending order: protocol 4 (0.819), protocol 2 (0.810), protocol 3 (0.772), protocol 1 (0.765) and there were no significant differences between any two protocols (P>0.05).In four protocols, the sensitivity in order were 45.40%, 56.30%, 59.70%, 61.34%, while the specificity in order were 95.10%, 96.10%, 89.80%, 96.60%, and the accuracy in order were 76.85%, 81.48%, 78.70%, 83.65%.Conclusion Multiparametric MRI can improve the diagnostic accuracy for the detection of early PCa, and T2WI+DWI+DCE is with the highest value.The PI-RADS V2 system is a better semi quantitative method for evaluation of early PCa.
8.Design,synthesis and anti-tumor activities in vitro of novel 3-substituted indolin-2-one compounds
Hao ZHOU ; Feng ZHOU ; Youjun ZHOU
Journal of Pharmaceutical Practice 2015;(2):131-133,142
Objective To compose and evaluate anti‐tumor activities of 3‐substituted indole‐2‐one compounds which may have dual inhibitory activities against both tubulin protein and VEGFR‐2 tyrosine kinase .Methods Target compounds were prepared starting from substituted aniline viacondensation ,cyclization and reduction .Results 11 target compounds were syn‐thesized and all the compounds displayed moderate anti‐proliferative activities against three tumor cell lines .Compound j9 showed a certain inhibitory activity against both VEGFR‐2 kinase and tubulin protein in vitro .Conclusion This series of indo‐lin‐2‐one derivatives were found to be a novel kind of multi‐target inhibitor .
9.Binding of Shewanella FadR to the fabA fatty acid biosynthetic gene: implications for contraction of the fad regulon.
Huimin ZHANG ; Beiwen ZHENG ; Rongsui GAO ; Youjun FENG
Protein & Cell 2015;6(9):667-679
The Escherichia coli fadR protein product, a paradigm/prototypical FadR regulator, positively regulates fabA and fabB, the two critical genes for unsaturated fatty acid (UFA) biosynthesis. However the scenario in the other Ɣ-proteobacteria, such as Shewanella with the marine origin, is unusual in that Rodionov and coworkers predicted that only fabA (not fabB) has a binding site for FadR protein. It raised the possibility of fad regulon contraction. Here we report that this is the case. Sequence alignment of the FadR homologs revealed that the N-terminal DNA-binding domain exhibited remarkable similarity, whereas the ligand-accepting motif at C-terminus is relatively-less conserved. The FadR homologue of S. oneidensis (referred to FadR_she) was over-expressed and purified to homogeneity. Integrative evidence obtained by FPLC (fast protein liquid chromatography) and chemical cross-linking analyses elucidated that FadR_she protein can dimerize in solution, whose identity was determined by MALDI-TOF-MS. In vitro data from electrophoretic mobility shift assays suggested that FadR_she is almost functionally-exchangeable/equivalent to E. coli FadR (FadR_ec) in the ability of binding the E. coli fabA (and fabB) promoters. In an agreement with that of E. coli fabA, S. oneidensis fabA promoter bound both FadR_she and FadR_ec, and was disassociated specifically with the FadR regulatory protein upon the addition of long-chain acyl-CoA thioesters. To monitor in vivo effect exerted by FadR on Shewanella fabA expression, the native promoter of S. oneidensis fabA was fused to a LacZ reporter gene to engineer a chromosome fabA-lacZ transcriptional fusion in E. coli. As anticipated, the removal of fadR gene gave about 2-fold decrement of Shewanella fabA expression by β-gal activity, which is almost identical to the inhibitory level by the addition of oleate. Therefore, we concluded that fabA is contracted to be the only one member of fad regulon in the context of fatty acid synthesis in the marine bacteria Shewanella genus.
Amino Acid Sequence
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Bacterial Proteins
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chemistry
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metabolism
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Base Sequence
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Binding Sites
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DNA, Bacterial
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metabolism
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Escherichia coli
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genetics
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metabolism
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Fatty Acid Synthase, Type II
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genetics
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metabolism
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Fatty Acids
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biosynthesis
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Gene Expression Regulation, Bacterial
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drug effects
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Molecular Sequence Data
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Oleic Acid
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pharmacology
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Protein Binding
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drug effects
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Regulon
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genetics
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Repressor Proteins
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chemistry
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metabolism
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Shewanella
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genetics
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metabolism
10.Gluconate 5-dehydrogenase (Ga5DH) participates in Streptococcus suis cell division.
Zhongyu SHI ; Chunling XUAN ; Huiming HAN ; Xia CHENG ; Jundong WANG ; Youjun FENG ; Swaminath SRINIVAS ; Guangwen LU ; George F GAO
Protein & Cell 2014;5(10):761-769
Bacterial cell division is strictly regulated in the formation of equal daughter cells. This process is governed by a series of spatial and temporal regulators, and several new factors of interest to the field have recently been identified. Here, we report the requirement of gluconate 5-dehydrogenase (Ga5DH) in cell division of the zoonotic pathogen Streptococcus suis. Ga5DH catalyzes the reversible reduction of 5-ketogluconate to D-gluconate and was localized to the site of cell division. The deletion of Ga5DH in S. suis resulted in a plump morphology with aberrant septa joining the progeny. A significant increase was also observed in cell length. These defects were determined to be the consequence of Ga5DH deprivation in S. suis causing FtsZ delocalization. In addition, the interaction of FtsZ with Ga5DH in vitro was confirmed by protein interaction assays. These results indicate that Ga5DH may function to prevent the formation of ectopic Z rings during S. suis cell division.
Bacterial Proteins
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chemistry
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genetics
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metabolism
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Cell Division
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Cell Shape
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Cytoskeletal Proteins
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chemistry
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genetics
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metabolism
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Mutation
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Oxidoreductases
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deficiency
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genetics
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metabolism
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Protein Binding
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Streptococcus suis
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enzymology

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