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Epithelial defect repair in the auricle and auditory meatus by grafting with cultured adipose-derived mesenchymal stem cell aggregate-extracellular matrix

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Chinese Medical Journal 2019年第6期132卷 680-689页

作者： Wen-Jin Zhang Lei-Guo Ming Jian-Jun Sun Center of Otolaryngology Head and Neck Surgery Chinese PLA Navy General Hospital Beijing 100048 China School of Postgraduate Anhui Medical University Hefei Anhui 230032 China State Key Laboratory of Military Stomatology Center for Tissue Engineering School of Stomatology Fourth Military Medical University Xi'an Shaanxi 710032 China Research and Development Center for Tissue Engineering Fourth Military Medical University Xi'an Shaanxi 710032 China

Background: Several patients experience persistent otorrhea after a flawless surgical procedure because of insufficient epithelial healing. Several efforts, such as autologous tissue allograft and xenograft, have been made to halt otorrhea. However, a stable technology to induce temporal epithelial repair is yet to be established. Therefore, this study aims to investigate whether implantation of seeding adipose-derived mesenchymal stem cell (ADMSC) aggregates on extracellular matrix (ECM;herein, ADMSC aggregate-ECM) into damaged skin wound promotes skin regeneration. Methods: ADMSC aggregate-ECM was prepared using a previously described procedure that isolated ADMSCs from rabbits and applied to the auricle and auditory meatus wound beds of New Zealand white rabbits. Wound healing was assessed by general observation and hematoxylin and eosin (H&E) staining. Secretion of growth factor of the tissue was evaluated by western blotting. Two other groups, namely, ECM and control, were used. Comparisons of three groups were conducted by one-way analysis of variance analysis. Results: ADMSCs adhered tightly to the ECM and quickly formed cell sheets. At 2 weeks, general observation and H&E staining indicated that the wound healing rates in the ADMSC aggregate-ECM (69.02±6.36%) and ECM (59.32 + 4.10%) groups were higher than that in the control group (43.74± 12.15%;P=0.005, P<0.001, respectively) in ear auricle excisional wounds. At 7 weeks, The scar elevation index was evidently reduced in the ADMSC aggregate-ECM (2.08±0.87) and ECM (2.31 ±0.33) groups compared with the control group (4.06 ±0.45;P < 0.001, P < 0.001, respectively). In addition, the scar elevation index of the ADMSC aggregate-ECM group reached the lowest rate 4 weeks in advance. In auditory meatus excisional wounds, the ADMSC aggregate-ECM group had the largest range of normal skin-like structure at 4 weeks. The ADMSC aggregate-ECM and ECM groups secreted increased amounts of growth factors that contributed to skin regeneration at weeks 1 and 2, respectivel

关键词： Adipose-derived mesenchymal stem cell Extracellular matrix Otorrhea Rabbit Skin regeneration Wound healing

Effect of Nb addition on microstructure and mechanical properties of 25CrNiMoV(DZ2)steel for high-speed railway axles

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Journal of Iron and Steel Research(International) 2022年第5期29卷 802-809页

作者： jin-wen zhang Yan-guang Cao Cheng-guo zhang Zhao-dong Li wen-xian Wang College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Technology Center Taiyuan Iron and Steel(Group)Co.Taiyuan030003ShanxiChina Department of Structural Steels Central Iron and Steel Research InstituteBeijing100081China Locomotive and Car Research Institute China Academy of Railway Sciences Corporation LimitedBeijing100081China

The microstructure,precipitates and properties of 25CrNiMoV(DZ2)steel for high-speed railway axles with different Nb contents were investigated by means of optical microscopy,scanning electron microscopy,electron back-scattering diffraction,transmission electron microscopy and physicochemical phase analysis.The results show that the grain size of the original austenite of the test steels decreases from 20.5 to 14.2 and 10.8μm after adding 0.026 and 0.039 wt.%Nb to a 25CrNiMoV steel,respectively.Moreover,the block width of the tempered martensite in the test steels is refined from 1.91 to 1.72 and 1.60µm,respectively.MC-type precipitates in 25CrNiMoV steel are mainly VC,while(Nb,V)C gradually precipitates when Nb is microalloyed,and the amount of precipitates increases with increasing Nb content.Through strengthening mechanism analysis,it is found that grain refinement strengthening is the primary way to increase the strength.The improvement in the yield strength with increasing Nb content is attributed to a significant increase in precipitation strengthening,grain refinement strengthening and dislocation strengthening.

关键词： High-speed railway axle steel Nb microalloying Precipitate Strengthening mechanism

One dimensional carbon-based composites as cathodes for lithium-sulfur battery

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Journal of Materials Science & Technology 2022年第27期122卷 101-120页

作者： jin Luo Keke Guan wen Lei Shaowei zhang Quanli Jia Haijun zhang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081China College of Engineering Mathematics and Physical SciencesUniversity of ExeterExeter EX44QFUnited Kingdom Henan Key Laboratory of High Temperature Functional Ceramics Zhengzhou UniversityZhengzhou 450052China

Lithium-sulfur batteries(LSBs),owing to their much higher energy density compared to the traditional lithium-ion battery,are deemed as one of the most promising candidates for the energy storage system.However,several issues including shuttle effect,lithium dendrites,and volumetric expansion seriously impede the commercial applications of LSBs.One-dimensional carbon materials(1DCMs)have been widely used as the matrix material for LSBs due to their high surface area,superior conductivity,good flexibility,excellent mechanical stability,and functional modifiability.In this review,the recent progress in 1D carbon-based composites as cathode including metal compounds/1DCMs,MOFs/1DCMs,MXenes/1DCMs,and polymers/1DCMs were discussed.Different strategies for polysulfide confinement and analysis of the functions of various components in the composites were summarized detailly.In the end,the current challenges of LSBs were systematically summarized,and the future outlooks were proposed,aiming at providing a comprehensive insight into the design of new host materials for nextgeneration LSBs.

关键词： One-dimensional carbon materials Composites Lithium-sulfur batteries Cathode Suttle effect

Phenomenological study of the anisotropic quark matter in the two-flavor Nambu–Jona–Lasinio model

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Nuclear Science and Techniques 2022年第11期33卷 170-190页

作者： He-Xia zhang Yu-Xin Xiao jin-wen Kang Ben-Wei zhang Key Laboratory of Quark and Lepton Physics(MOE)and Institute of Particle Physics Central China Normal UniversityWuhan 430079China Guangdong Provincial Key Laboratory of Nuclear Science Institute of Quantum MatterSouth China Normal UniversityGuangzhou 510006China

With the two-flavor Nambu–Jona–Lasinio (NJL) model, we carried out a phenomenological study on the chiral phase structure, mesonic properties, and transport properties of momentum-space anisotropic quark matter. To calculate the transport coefficients we utilized the kinetic theory in the relaxation time approximation, where the momentum anisotropy is embedded in the estimation of both the distribution function and relaxation time. It was shown that an increase in the anisotropy parameterξmay result in a catalysis of chiral symmetry breaking. The critical endpoint(CEP) is shifted to lower temperatures and larger quark chemical potentials asξincreases, and the impact of momentum anisotropy on the CEP temperature is almost the same as that on the quark chemical potential of the CEP. The meson masses and the associated decay widths also exhibit a significant ξ dependence. It was observed that the temperature behavior of the scaled shear viscosity η/T~3 and scaled electrical conductivity σ/T exhibited a similar dip structure, with the minima of both η/T~3 and σ/T shifting toward higher temperatures with increasing ξ. Furthermore,we demonstrated that the Seebeck coefficient S decreases when the temperature rises and its sign is positive, indicating that the dominant carriers for converting the temperature gradient to the electric field are up-quarks. The Seebeck coefficient S is significantly enhanced with a largeξfor a temperature below the critical temperature.

关键词： Heavy-ion collision Momentum anisotropy NJL model Chiral phase transition Transport coefficient Quark matter

Applications of single-cell RNA sequencing in spermatogenesis and molecular evolution

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Zoological Research 2024年第3期45卷 575-585页

作者： wen-Bo Chen Meng-Fei zhang Fan Yang jin-Lian Hua College of Veterinary Medicine Shaanxi Centre of Stem Cells Engineering&TechnologyNorthwest A&F UniversityYanglingShaanxi 712100China Key Laboratory of Livestock Biology Northwest A&F UniversityYanglingShaanxi 712100China

Spermatogenic cell heterogeneity is determined by the complex process of spermatogenesis differentiation.However,effectively revealing the regulatory mechanisms underlying mammalian spermatogenic cell development and differentiation via traditional methods is difficult.Advances in technology have led to the emergence of many single-cell transcriptome sequencing protocols,which have partially addressed these challenges.In this review,we detail the principles of 10x Genomics technology and summarize the methods for downstream analysis of single-cell transcriptome sequencing data.Furthermore,we explore the role of single-cell transcriptome sequencing in revealing the heterogeneity of testicular ecological niche cells,delineating the establishment and disruption of testicular immune homeostasis during human spermatogenesis,investigating abnormal spermatogenesis in humans,and,ultimately,elucidating the molecular evolution of mammalian spermatogenesis.

关键词： Single-cell RNA sequencing(scRNA-seq) Spermatogenesis Molecular evolution Sertoli cell

The dynamic response of a high-density polyethylene slow-release structure under launching overload

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Defence Technology（防务技术） 2023年第8期26卷 143-156页

作者： Ke-Bin zhang wen-Bin Li Yu Zheng wen-jin Yao Chang-Fang Zhao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China

Based on the 60 mm artillery grenade,a slow-release structure was designed to reduce the severity of ammunitions response to accidental thermal stimulation and improve the thermal stability of ammunitions.The slow-release structure was made of high-density polyethylene(HDPE) and connected the fuse and the projectile body through internal and external threads.To study the safety of the slowrelease structure under artillery launching overload,mechanical analysis of the slow-release structure was simulated via finite element analysis(FEA).The impacts of various factors(e.g.,fuse mass,number of threads,and nominal diameter of internal threads of the slow-release structure) on the connection strength of the slow-release structure were studied.A strength-prediction model based on the fuse mass and internal thread parameters was established by fitting the maximum effective stress of the slowrelease structure.This led to good prediction results.In conclusion,this study provides references and theoretical support for the design of thermal protection structures insensitive to ammunition.

关键词： Artillery ammunition HDPE Finite element analysis Slow-release structure Threaded connection

Poor outcomes of delirium in the intensive care units are amplified by increasing age: A retrospective cohort study

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World Journal of Emergency Medicine 2021年第2期12卷 117-123页

作者： wen Gao Yu-ping zhang jing-fen jin Nursing Department School of MedicineZhejiang UniversityHangzhou 310058China Nursing Department the Second Affi liated Hospital of Zhejiang University School of MedicineHangzhou 310009China

BACKGROUND: Delirium in patients in intensive care units(ICUs) is an acute disturbance and fluctuation of cognition and consciousness. Though increasing age has been found to be related to ICU delirium, there is limited evidence of the effect of age on delirium outcomes. The aim of this study is to investigate the relationship between age categories and outcomes among ICU delirium patients.METHODS: Data were extracted from the electronic ICU(e ICU) Collaborative Research Database with records from 3,931 patients with delirium. Patients were classified into non-aged(<65 years), youngold(65–74 years), middle-old(75–84 years), and very-old(≥85 years) groups. A Cox regression model was built to examine the role of age in death in ICU and in hospital after controlling covariates. RESULTS: The sample included 1,667(42.4%) non-aged, 891(22.7%) young-old, 848(21.6%) middle-old, and 525(13.3%) very-old patients. The ICU mortality rate was 8.3% and the hospital mortality rate was 15.4%. Compared with the non-aged group, the elderly patients(≥65 yeras) had higher mortality at ICU discharge(χ2=13.726, P=0.001) and hospital discharge(χ2=56.347, P<0.001). The Cox regression analysis showed that age was an independent risk factor for death at ICU discharge(hazard ratio [HR]=1.502, 1.675, 1.840, 95% confidence interval [CI] 1.138–1.983, 1.250–2.244, 1.260–2.687;P=0.004, 0.001, 0.002 for the young-, middle-and very-old group, respectively) as well as death at hospital discharge(HR=1.801, 2.036, 2.642, 95% CI 1.454–2.230, 1.638–2.530, 2.047–3.409;all P<0.001).CONCLUSIONS: The risks of death in the ICU and hospital increase with age among delirious patients.

关键词： Intensive care Delirium Aging Mortality

Timing of brain computed tomography for predicting neurological prognosis in comatose cardiac arrest survivors: a retrospective observational study

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World Journal of Emergency Medicine 2022年第5期13卷 349-354页

作者： Gan-nan Wang Zhong-man zhang wen Chen Xiao-quan Xu jin-song zhang Department of Emergency the First Affi liated Hospital of Nanjing Medical UniversityNanjing 210029China Department of Radiology the First Affi liated Hospital of Nanjing Medical UniversityNanjing 210029China

BACKGROUND:To assess the association between relevant brain computed tomography(CT)parameters at different time and neurological prognosis in adult comatose survivors after cardiac arrest(CA).METHODS:A total of 94 CA patients who underwent early and late CT scans(within 24 h and 24 h to 7 d respectively after CA)between January 2018 and April 2020 were enrolled in this retrospective study.According to the Cerebral Performance Category(CPC)score at hospital discharge,the patients were divided into either a good outcome(CPC 1-2)group or a poor-outcome group(CPC 3-5).The grey-to-white matter ratio(GWR)and the proportion of cerebrospinal fluid volume(pCSFV)were measured.In predicting poor outcomes,the prognostic performance of relevant CT parameters was evaluated,and the comparison analysis(expressed as the ratio of parameters in late CT to those in the early CT)of diff erent CT time was conducted.RESULTS:Totally 26 patients were in the good-outcome group,while 68 patients were in the poor-outcome group.The putamen density,GWR,and pCSFV in late CT were significantly lower in the poor-outcome group(P24 h after CA may be a good choice as a neuroimaging approach to evaluating prognosis.To predict neurological prognosis,comparison analysis of diff erent CT time can be used as another promising tool in comatose CA survivors.

关键词： Cardiac arrest Brain computed tomography Cerebral edema Coma Prognosis

Oxidized Nb_(2)C MXene as catalysts for lithium-sulfur batteries:Mitigating the shuttle phenomenon by facilitating catalytic conversion of lithium polysulfides

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Journal of Materials Science & Technology 2022年第24期119卷 45-52页

作者： Cailing Song wen zhang Qianwen jin Yan Zhao Yongguang zhang Xin Wang Zhumabay Bakenov School of Materials Science and Engineering State Key Laboratory of Reliability and Intelligence of Electrical EquipmentHebei University of TechnologyTianjin 300130China South China Academy of Advanced Optoelectronics&International Academy of Optoelectronics at Zhaoqing South China Normal UniversityGuangzhou 510006China Department of Chemical and Materials Engineering National Laboratory AstanaInstitute of Batteries LLPNazarbayev UniversityNur-Sultan 010000Kazakhstan

Extensive research has been devoted to lithium-sulfur(Li-S)batteries due to their overwhelming promises and advantages such as high theoretical capacity(1675 m Ah g^(-1)),extremely cost effectiveness and abundance and availability of sulfur.Nevertheless,a sluggish electrochemical kinetics of the battery limited by a slow conversion of lithium polysulfide(LiPSs)intermediates and Li PSs shuttle effect severely hinder its development towards industrial application.Herein,we designed the oxidized Nb2_(C)MXene with amorphous carbon(Nb_(2)O_(5)/C)composites as sulfur host using CO_(2)treatment to address the above issues.The Nb_(2)O_(5)/C composites with high conductivity are directly employed as sulfur hosts for Li-S battery capable to remarkably mitigate the shuttle phenomenon due to a combined effect of their Li PSs trapping ability and catalytic activity towards their accelerated conversion.Meanwhile,the unique layered structure of the composite facilitates ion transfer and accommodates the volume changes of the cathode during cycling.With this rational design,the resultant Li-S batteries exhibit superior electrochemical performance with a high initial specific capacity of 745 m Ah g^(-1)at 1.0 C and a reversible capacity of 620 m Ah g^(-1)at a high rate cycling at 3.0 C.

关键词： Oxidized Nb_(2)C MXene Li-S batteries Lithium polysulfides conversion Electrochemical performance