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Detection of plasmid-mediated IMP-1 metallo-β-lactamase and quinolone resistance determinants in an ertapenem-resistant Enterobacter cloacae isolate

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第5期10卷 348-354页

作者： Li-rong CHEN hong-wei zhou Jia-chang CAI Rong ZHANG Gong-xiang CHEN Clinical Laboratory Center the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China Cancer Institute Zhejiang University Hangzhou 310009 China

Objective： To investigate the mechanism of carbapenem resistance and the occurrence ofplasmid-mediated quinolone resistance determinants qnr and aac（6＇）-Ib-cr in a clinical isolate of Enterobacter cloacae. Methods： An ertapenem-resistant E. cloacae ZY106, which was isolated from liquor puris of a female gastric cancer patient in a Chinese hospital, was investigated. Antibiotic susceptibilities were determined by agar dilution method. Conjugation experiments, isoelectric focusing, polymerase chain reaction （PCR）, and DNA sequence analyses of plasmid-mediated carbapenemases and quinolone resistance determinants were preformed to confirm the genotype. Outer membrane proteins （OMPs） were examined by urea-sodium dodecyl sulfate- polyacrylamide gel electrophoresis （Urea-SDS-PAGE）. Results： Minimum inhibitory concentrations （MICs） of imipenem, mer- openem, and ertapenem for ZY 106 were 2, 4, and 16 pg/ml, respectively. Conjugation studies with Escherichia coli resulted in the transfer of significantly reduced carbapenem susceptibility. ZY106 produced IMP-1 metallo-β-lactamase and CTX-M-3 extended-spectrum β-1actamase, and E. coli transconjugant produced IMP-1. Plasrnid-mediated quinolone resistance determinant qnrS1 was detected in ZY106. Transfer of the qnrSl-encoding-plasmid into E. coli by conjugation resulted in intermediate resistance to ciprofloxacin in E. coli transconjugant. Urea-SDS-PAGE analysis of OMPs showed that ZYI06 lacked an OMP of approximately 38 kDa. Conclusion： It is the first IMP-l-producing Enterobacteriaceae in China and the first report of a clinical isolate that harbors both blalMP and qnrS genes as well. The blalMP-1, blaCTX-M-3, and qnrS1 are encoded at three different plasmids. IMP-1 combined with the loss of an OMP possibly resulted in ertapenem resistance and reduced imipenem and mero- penern susceptibility in E. cloacae.

关键词： Antibiotic resistance Carbapenem Enterobacteriaceae Outer membrane proteins (OMPs)

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Corneal endothelial cells and acoustic cavitation in phacoemulsification

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World Journal of Clinical Cases 2023年第8期11卷 1712-1718页

作者： Kai Chen Wen-Ya Xu Si-Si Sun hong-wei zhou Department of Ophthalmology Lianshui County People's HospitalHuai’an 223400Jiangsu ProvinceChina Department of Ophthalmology Huai’an 82 HospitalHuai'an 223001Jiangsu ProvinceChina Department of Industrial Engineering Tsinghua UniversityBeijing 100084China

Postoperative complications of phacoemulsification,such as corneal edema caused by human corneal endothelial cell(CEC)injury,are still a matter of *** several factors are known to cause CEC damage,the influence of ultrasound on the formation of free radicals during surgery should be *** in aqueous humor induces cavitation and promotes the formation of hydroxyl radicals or reactive oxygen species(ROS).ROS-induced apoptosis and autophagy in phacoemulsification have been suggested to significantly promote CEC *** cannot regenerate after injury,and measures must be taken to prevent the loss of CEC after phacoemulsification or other CEC *** can reduce the oxidative stress injury of CEC during *** from rabbit eye studies shows that ascorbic acid infusion during operation or local application of ascorbic acid during phacoemulsification has a protective effect by scavenging free radicals or reducing oxidative *** in experiments and clinical practice,hydrogen dissolved in the irrigating solution can also prevent CEC damage during phacoemulsification ***(AST)can inhibit oxidative damage,thereby protecting different cells from most pathological conditions,such as myocardial cells,luteinized granulosa cells of the ovary,umbilical vascular endothelial cells,and human retina pigment epithelium cell line(ARPE-19).However,existing research has not focused on the application of AST to prevent oxidative stress during phacoemulsification,and the related mechanisms need to be *** Rho related helical coil kinase inhibitor Y-27632 can inhibit CEC apoptosis after *** experiments are required to confirm whether its effect is realized through improving the ROS clearance ability of CEC.

关键词： Cataract Phacoemulsification Corneal endothelial cells Ultrasound Acoustic cavitation Oxidative stress Antioxidant

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Effects of Cataract Surgery on Endothelium in Transplanted Corneal Grafts： Comparison of Extracapsular Cataract Extraction and Phacoemulsification for Complicated Cataract after Penetrating Keratoplasty

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Chinese Medical Journal 2016年第17期129卷 2096-2101页

作者： hong-wei zhou Li-Xin Xie Department of Ophthalmology Renmin Hospital of Wuhan University Wuhan Hubei 430060 China State Key Laboratory Cultivation Base Shandong Provincial Key Laboratory of Ophthalmology Shandong Eye Institute Shandong Academy of Medical Sciences Qingdao Shandong 266071 China

Background： The endothelium should be carefully evaluated when choosing a surgical technique for cataract removal. Therefore, we aimed to study the effects of different cataract surgery techniques on endothelial cell loss in transplanted corneal grafts. Methods： A total of 54 patients who received complicated cataract surgery in post-penetrating keratoplasty （PKP） eyes at the Shandong Eye Institute between February 2001 and June 2014 were included, and clinical records were reviewed. Baseline demographic details, clinical characteristics, endothelial cell density （ECD）, and best-corrected visual acuity （BCVA） were recorded. Wilcoxon rank-sum test and Wilcoxon signed-rank test were used to test the equality of medians. A regression model was constructed to compare the reduced rate of ECD. Results： Of the 54 eyes included in this study, extracapsular cataract extraction （ECCE） was performed in 34 eyes of 33 patients （ECCE group） whereas phacoemulsification was performed in 20 eyes of 20 patients （phacoemulsification group）. There was no signifcant difference in the median age （P = 0.081） or preoperative ECD （P = 0.585） between the two groups. At 6 months after cataract surgery, ECD in ECCE group was significantly higher than that in phacoemulsification group （P = 0.043）. In addition, the endothelial cell loss rate in ECCE group was significantly lower than that in phacoemulsification group at 2 months （P = 0.018）, 4 months （P 〈 0.001）, and 6 months （P 〈 0.001） after cataract surgery. Endothelial cell loss rate after cataract surgery increased over the 6-month study duration in both ECCE group （P 〈 0.001） and phacoemulsification group （P 〈 0.001）, but phacoemulsification resulted in a greater reduction in ECD than that of ECCE in transplanted corneal grafts （P 〈 0.001）. There was no signifcant difference in postoperative BCVA between the two groups （P = 0.065）. Conclusion： ECCE is more suitable than phacoemulsification in cataract surgery in complicated cataract after

关键词： Complicated Cataract Corneal Endothelial Cell Extracapsular Cataract Extraction Penetrating Keratoplasty Phacoemulsification

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Masing Behavior and Microstructural Change of Quenched and Tempered High-Strength Steel Under Low Cycle Fatigue

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Acta Metallurgica Sinica(English Letters) 2019年第11期32卷 1346-1354页

作者： Feng-Mei Bai hong-wei zhou Xiang-Hua Liu Meng Song Ya-Xin Sun Hai-Long Yi Zhen-Yi Huang State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China School of Materials Science and Engineering Anhui Key Lab of Materials Science and ProcessingAnhui University of TechnologyMaanshan 243002China School of Metallurgical Engineering Anhui University of TechnologyMaanshan 243002China

Low cycle fatigue behavior of a quenched and tempered high-strength steel(Q960 E) was studied in the strain amplitude ranging from ± 0.5% to ± 1.2% at room temperature. As a result of fatigue loading, the dislocation structural evolution and fracture mechanism were examined and studied by transmission electron microscopy and scanning electron microscopy(SEM). The results showed that this Q960 E steel showed cyclic softening at different strain amplitudes, and the softening tendency was more apparent at strain amplitude of ±(0.6–1.2)% than that at ± 0.5%. The reduction in dislocation density with increasing strain amplitude is responsible for the softening tendency of cyclic stress with the strain amplitude. The material illustrates near-Masing behavior at strain amplitude ranging from ± 0.6% to ± 1.2%. The near-Masing behavior of Q960 E high-strength steel can be the result of stability of martensite lath at different strain amplitudes. Partial transformation from martensite laths to dislocation cells is responsible for the derivation from ideal Masing behavior. In the SEM examination of fracture surfaces, transgranular cracks initiate on the sample surface. Striations can be found during the crack propagation stage.

关键词： High-strength steel Low cycle fatigue Near-Masing behavior Martensite lath

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Coefficients of earth pressure at rest in thick and deep soils

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Mining Science and Technology 2009年第2期19卷 252-255页

作者： TIAN Qiu-hong XU Zhi-wei zhou Guo-qing ZHAO Xiao-dong HU Kun State Key Laboratory for Geomechanics ＆ Deep Underground Engineering School of Architecture and Civil Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

The effect of test methods and stress paths on the experimental value of the coefficient of earth pressure at rest, K0, was investigated under high pressures. The results indicate that the rigid pressure chamber and flexible lateral confining pressure medium method gives a stress ratio at the initial stage that is not the real K0. Moreover, K0 increases during the loading process becoming greater at high pressures. In the unloading process, however, K0 increases only at the initial stage but decreases thereafter. In addition, the incremental magnitude definition, K0=dσ3/dσ1, gives higher values than the total magnitude definition, K0=σ3/σ1, under loading. This is also true during initial stages of unloading. The experiment results also indicate that earth pressure at rest in deep and thick soils can be estimated by a power function of axial and confining pressures. It is necessary to choose the appropriate Kn to avoid some accidents.

关键词： experimental research earth pressure at rest loading and unloading paths thick and deep soils

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Effect of mixing rate and temperature on primary Si phase of hypereutectic Al-20Si alloy during control ed diffusion solidification(CDS) process

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China Foundry 2015年第3期12卷 173-179页

作者： Yuan-dong Li Xin-long Zhang Ying Ma Diran Apelian hong-wei zhou Xing-hai Liu State Key Lab. of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology Key Lab. of Nonferrous Metal Alloys and Processing Ministry of Education Lanzhou University of Technology Metal Processing Institute WPIWorcester MA 01609 USA.

Controlled Diffusion Solidification(CDS) is a promising process relied on mixing two liquid alloys of precisely controlled chemistry and temperature in order to produce a predetermined alloy composition. In this study, the CDS was employed to prepare hypereutectic Al-20%Si(mass fraction) alloy using Al-30%Si and pure Al of different temperatures. The mixing rate was controlled using three small crucibles with a hole of different diameters in their bottom. The effect of mixing rate and temperature on the microstructure of the primary Si-phase during the mixing of molten Al and Al-30%Si was studied. The results showed that when the diameter of the small crucible bottom hole is 16 mm, a higher mass mixing rate 0.217 kg·s-1 would results in a lower stream velocity 0.414 m·s-1. Conversely a lower mass mixing rate 0.114 kg·s-1(the diameter of the small crucible bottom hole is 8 mm) would result in a higher fluid stream velocity 0.879 m·s-1. A lower mass mixing rate would be better to refine the primary Si than a higher mass mixing rate. Meanwhile, the morphology and distribution of primary Si could also be improved. Especially, when Al-30%Si alloy at 820 °C was mixed with pure Al at 670 °C in the case of a mass mixing rate of 0.114 kg·s-1 and a pouring temperature of 680 °C, the average size of the primary Si phase would be only 18.2 μm. Its morphology would mostly be octahedral and the primary Si would distribute uniformly in the matrix microstructure. The lower mass mixing rate(0.114 kg·s-1) will enhance the broken tendency of Al-30%Si steam and the mixing agitation of resultant melt, so the primary Si phase can be better refined.

关键词： Controlled Diffusion Solidification(CDS) hypereutectic Al-Si alloy mass mixing rate stream velocity primary Si

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Machine Learning Models in Type 2 Diabetes Risk Prediction:Results from a Cross-sectional Retrospective Study in Chinese Adults

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Current Medical Science 2019年第4期39卷 582-588页

作者： Xiao-lu XIONG Rong-xin ZHANG Yan BI wei-hong zhou Yun YU Da-long ZHU Department of Endocrinology Nanjing Drum Tower Hospital Clinical College of Nanjing Medical UniversityNanjing 210008China School of Biomedical Engineering and Informatics Nanjing Medical UniversityNanjing 211166China

Type 2 diabetes mellitus (T2DM) has become a prevalent health problem in China,especially in urban *** prevention strategies are needed to reduce the associated mortality and *** applied the combination of rules and different machine learning techniques to assess the risk of development of T2DM in an urban Chinese adult population.A retrospective analysis was performed on 8000 people with non-diabetes and 3845 people with T2DM in *** Perceptron (MLP),AdaBoost (AD),Trees Random Forest (TRF),Support Vector Machine (SVM),and Gradient Tree Boosting (GTB) machine learning techniques with 10 cross validation methods were used with the proposed model for the prediction of the risk of development of *** performance of these models was evaluated with accuracy,precision,sensitivity,specificity,and area under receiver operating characteristic (ROC) curve (AUC).After comparison,the prediction accuracy of the different five machine models was 0.87,0.86,0.86,0.86 and 0.86 *** combination model using the same voting weight of each component was built on T2DM,which was performed better than individual *** findings indicate that,combining machine learning models could provide an accurate assessment model for T2DM risk prediction.

关键词： type 2 diabetes risk prediction machine learning

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Functional decoration on a regenerable bifunctional porous covalent organic framework probe for rapid detection and adsorption of copper ions

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Rare Metals 2024年第2期43卷 758-769页

作者： Yu-Long Li Xi-Lang Jin Yi-Ting Ma Jing-Rui Liu Fazal Raziq Peng-Yuan Zhu Zhi-Feng Deng hong-wei zhou wei-Xing Chen Wen-Huan Huang School of Materials and Chemical Engineering Xi’an Technological UniversityXi’an710021China Yulin Boyi-Jingking Research Institute of Industrial Technology Development Research Yulin719054China KAUST Catalysis Center King Abdullah University of Science and Technology23955-6900ThuwalKingdom of Saudi Arabia Key Laboratory of Chemical Additives for China National Light Industry College of Chemistry and Chemical EngineeringShaanxi University of Science and TechnologyXi’an710021China National and Local Joint Engineering Laboratory for Slag Comprehensive Utilization and Environmental Technology School of Materials Science and EngineeringShaanxi University of TechnologyHanzhong723001China

Developing fluorescence porous probe for detecting and eliminating Cu^(2+) contamination in water or biosystem is an essential research project that has attracted considerable ***,improving the fluorescence detecting efficiency while enhancing the adsorption capacity of the porous probe is of great ***,a bifunctional two-dimensional imine-based porous covalent organic framework(TTP-COF)probe was designed and synthesized from 1,3,5-tris(4-aminophenyl)benzene(TAPB)and 2,4,6-Triformylphloroglucinol(TP)***-COF displayed rapid detection of Cu^(2+)(limit of detection(LOD)=10 nmol·L^(−1) while achieving a high adsorption capacity of 214 mg·g^(−1)(pH=6)at room temperature with high reusability(>5 cycles).The key roles and contributions of highπ-conjugate and delocalized electrons in TABP and functional–OH groups in TP were *** importantly,the fluorescence quenching mechanism of TTP-COF was studied by density functional theory theoretical calculations,revealing the crucial role of intramolecular hydrogen bonds among C=N and–OH groups and the blocking of the excited state intramolecular proton transfer process in detecting process of Cu^(2+).

关键词： Covalent organic framework(COF) Excited-state intramolecular proton transfer(ESIPT) Copper ion detection Copper ion adsorption Renewability

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3D T1-weighted black blood sequence at 3.0 Tesla for the diagnosis of cervical artery dissection

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Stroke & Vascular Neurology 2016年第3期1卷 140-146页

作者： Yun Luo Zhen-Ni Guo Peng-Peng Niu Yang Liu hong-wei zhou Hang Jin Yi Yang Stroke Center Neuroscience CenterDepartment of NeurologyThe First Hospital of Jilin UniversityChangchunChina Department of Radiology The First Hospital of Jilin UniversityChangchunChina

Objective:We aimed to investigate the value of threedimensional(3D)T1 volumetric isotropic turbo spin echo acquisition(VISTA)in the diagnosis of cervical artery dissection(CAD).Methods:We prospectively included patients who were suspected as having a CAD within 1 month of *** T1 VISTA,the diagnosis of the dissection was based on the presence of intramural high-signal,intimal flap,double lumen and aneurysmal *** final diagnosis of dissection was based on the clinical history,physical examination,and all of the imaging ***:A total of 46 patients were included in this *** final diagnosis of CAD was made for 21 *** of dissection was made for 20 of the 21 patients after assessing T1 VISTA.A definitive diagnosis of dissection was not made for 5 patients(including 3 patients with digital subtraction angiography)before the T1 VISTA *** sensitivity and specificity for T1 VISTA were 95.2%(95%CI,76.2%to 99.9%)and 100%(95%CI,86.3%to 100%),*** agreement between the two researchers for T1 VISTA for diagnosis of CAD was very good(k=0.91).For patients without acute artery occlusion,all of them had a definite conclusion with or without dissection by T1 VISTA(n=29).However,for 17 patients with acute artery occlusion,the possibility of dissection could not be excluded for 6 of them by T1 VISTA(p=0.001).Conclusions:3D T1 VISTA at 3.0 Tesla was useful in the diagnosis of acute ***,for some patients with total occlusion of the artery without typical imaging features of dissection,the unequivocal distinction between intramural haematoma and intraluminal thrombus may be not adequate by T1 VISTA *** studies should investigate whether a follow-up scan,a contrast-enhanced imaging or an optimal VISTA technique could be useful.

关键词： diagnosis alone VISTA

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Microstructural evaluation and mechanical properties of 7075 aluminum alloy prepared by controlled diffusion solidification

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China Foundry 2019年第4期16卷 238-247页

作者： Xiong Yang Yuan-dong Li Xiao-mei Luo hong-wei zhou Qi-yong Cai Ming Li Ying Ma State Key Laboratory ofAdvanced Processing and Recycling of Non-ferrous Metals Lanzhou University of Technology Lanzhou 730050 China Key Lab of Non-ferrous Metal Alloys and Processing Ministry of Education Lanzhou University of Technology L anzhou 730050 China

In the present work, 7075 aluminum alloy(Al-Zn-Mg-Cu) was produced by both conventional casting(CC) and controlled diffusion solidification(CDS) methods. Each sample was subjected to different heat-treatment conditions: as-cast, T4, and T6;and their microstructural and mechanical properties were investigated by optical microscopy(OM), scanning electron microscopy(SEM) and X-ray diffractometry(XRD). It was found that CDS promoted the formation of non-dendritic primary α-Al phase and reduced shrinkage porosity, thus resulting in improved mechanical properties. In addition, the eutectic phase of the CDS samples mainly consisted of T(Al-ZnMg-Cu) phase, which manifested a well-developed lamellar eutectic structure. However, in the CC samples, the T(Al-Zn-Mg-Cu) phase was composed of rod-like eutectics. Moreover, the θ(Al2 Cu) eutectic contents in the CC samples were greater than those in the CDS samples. Each element in the CC samples had an obvious change in the grain boundary, whereas the change in element content in the CDS samples was gradual. Therefore, the non-dendritic morphology of the primary phase and the presence of rod-like eutectics in the matrix of the CDS samples led to enhanced tensile strength and elongation under different heat treatment conditions.

关键词： primary α-Al phase eutectic phase solute atoms tensile strength elongation

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