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生物医学与环境科学:英文版 2023年第8期36卷 725-731页

作者： MAO Yu GAO Li Qin jia Li yun HOU Si Meng XIAO yuan yuan JI Xi Wen WANG Shuang Beijing Tongren Eye Center Beijing Ophthalmology and Visual Science Key LabBeijing Tongren HospitalCapital Medical UniversityBeijing 100730China Beijing Institute of Ophthalmology Beijing Tongren Eye CenterBeijing Ophthalmology and Visual Science Key LabBeijing Tongren HospitalCapital Medical UniversityBeijing 100730China

Objective To investigate the clinical efficacy of dexamethasone vitreous cavity implants(Ozurdex)for the treatment of macular edema(Irvine-Gass Syndrome)after cataract surgery.Method Eight patients(eight eyes)with Irvine-Gass syndrome were enrolled for vitreous injections with Ozurdex.The patients included six men(six eyes)and two women(two eyes)with a mean age of 67.12±11.92 years.Changes in the patients best-corrected visual acuity(BCVA),central macular thickness(CMT),and intraocular pressure were compared before and after treatment.Result The mean visual acuity BCVA of the patients was 0.81±0.26 before implantation,which improved to 0.20±0.12,0.13±0.09,and 0.15±0.13 at 2 weeks,1 month,and 3 months after implantation,respectively(P<0.001).The patient’s mean CMT before implantation was 703.00±148.88μm,and it reduced to 258.87±37.40μm,236.25±28.74μm,and 278.00±76.82μm at 2 weeks,1 month,and 3 months after implantation,respectively(P<0.001).Conclusion The dexamethasone vitreous cavity implant(Ozurdex)is a safe and effective treatment,which can effectively improve patient’s visual acuity and reduce macular edema associated with cataract surgery.

关键词： Irvine-Gass Syndrome Macular edema Dexamethasone Vitreous injection

Identification of a cytochrome P450 from Tripterygium hypoglaucum(Levl.)Hutch that catalyzes polpunonic acid formation in celastrol biosynthesis

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Chinese Journal of Natural Medicines 2022年第9期20卷 691-700页

作者： CHEN Xiao-Chao LU yun LIU yuan ZHOU jia-Wei ZHANG Yi-Feng GAO Hai-yun LIDan GAO Wei School of Traditional Chinese Medicine Capital Medical UniversityBeijing 100069China Beijing Shijitan Hospital Capital Medical UniversityBeijing 100038China

Tripterygium hypoglaucum(Levl.)Hutch,a traditional Chinese medicinal herb with a long history of use,is widely distributed in China.One of its main active components,celastrol,has great potential to be developed into anti-cancer and anti-obesity drugs.Although it exhibits strong pharmacological activities,there is a lack of sustainable sources of celastrol and its derivatives,making it crucial to develop novel sources of these drugs through synthetic biology.The key step in the biosynthesis of celastrol is considered to be the cyclization of 2,3-oxidosqualene into friedelin under the catalysis of 2,3-oxidosqualene cyclases.Friedelin was speculated to be oxidized into celastrol by cytochrome P450 oxidases(CYP450s).Here,we reported a cytochrome P450 ThCYP712K1 from Tripterygium hypoglaucum(Levl.)Hutch that catalyzed the oxidation of friedelin into polpuonic acid when heterologously expressed in yeast.Through substrate supplementation and in vitro enzyme analysis,ThCYP712K1 was further proven to catalyze the oxidation of friedelin at the C-29 position to produce polpunonic acid,which is considered a vital step in the biosynthesis of celastrol,and will lay a foundation for further analysis of its biosynthetic pathway.

关键词： Tripterygium hypoglaucum Cytochrome P450 Polpunonic acid Celastrol Biosynthesis

On establishment of novel constitutive model for directionally solidified nickel-based superalloys utilizing machine learning methods

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中国铸造:英文版 2023年第5期20卷 365-375页

作者： jia-yan Sun Rong Yin Ye-yuan Hu yun-xiang Tan Qing-yan Xu Key Laboratory for Advanced Materials Processing Technology(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Xiaomi AI Lab Beijing100102China

To enhance the accuracy of mechanical simulation in the directional solidification process of turbine blades for heavy-duty gas turbines,a new constitutive model that employs machine learning methods was developed.This model incorporates incremental learning and transfer learning,thus improves the predictive accuracy and generalization performance.To account for the anisotropy of the directionally solidified alloy,a deformation direction parameter is added to the model,enabling prediction of the stress-strain relationship of the alloy under different deformation directions.The predictive capabilities of both models are evaluated using correlation coefficient(R),average relative error(δ),and value of relative error(RE).Compared to the traditional model,the machine learning constitutive model achieves higher prediction accuracy and better generalization performance.This offers a new approach for the establishment of flow constitutive models for other directionally solidified and single-crystal superalloys.

关键词： Ni-based superalloy constitutive model machine learning directional solidification anisotropy

Direct ink writing of TiC-316L metal matrix composites with an epoxy resin-absolute ethanol system

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Rare Metals 2021年第3期40卷 590-599页

作者： Tao Lin Liu-Ping Jin Jia-Yun yuan Hui-Ping Shao Fu-Cheng Yu Wen-yuan Li Xin-Bo He Xin Deng Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China School of Material Science and Engineering Lanzhou University of TechnologyLanzhou 730050China Jihua Laboratory Chengye MansionFoshan 528299China School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006China

TiC-316 L metal matrix composites were successfully printed with an epoxy resin-absolute ethanol system by direct ink writing(DIW) process in this study.Microstructure and fracture morphology of the samples were observed by a scanning electron microscope(SEM).Also,the relative density,hardness and transverse rupture strength(TRS) of the sintered samples were tested.The results show that the samples prepared with a new epoxy resin-absolute ethanol system by the DIW process have high solid content of printing slurry,good surface roughness,high relative density and high strength.The solid content of the slurry suitable for DIW was 60 vol%,and the internal diameter of the nozzle was set to 0.4 mm,the printing speed was set to 30 mm·s^(-1),and the layer height was set to 0.36 mm.For the sample with 35 wt% TiC-316 L,the relative density,hardness and TRS of the sintered sample can reach 99.3%,HRA 79.5 and 1438 MPa,respectively.

关键词： DIW MMCs Epoxy resin TiC 316L

Neural progenitor cells derived from fibroblasts induced by small molecule compounds under hypoxia for treatment of Parkinson’s disease in rats

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Neural Regeneration Research 2023年第5期18卷 1090-1098页

作者： Yu Guo yuan-yuan Wang Ting-Ting Sun jia-jia Xu Pan Yang Cai-yun Ma Wei-Jun Guan Chun-Jing Wang Gao-Feng Liu Chang-Qing Liu School of Laboratory Medicine School of Life SciencesBengbu Medical CollegeBengbuAnhui ProvinceChina National Germplasm Resource Center for Domestic Animals Institute of Animal ScienceChinese Academy of Agricultural ScienceBeijingChina Department of Neuroscience University of Connecticut Health CenterFarmingtonCTUSA

Neural progenitor cells(NPCs) capable of self-renewal and differentiation into neural cell lineages offer broad prospects for cell therapy for neurodegenerative diseases. However, cell therapy based on NPC transplantation is limited by the inability to acquire sufficient quantities of NPCs. Previous studies have found that a chemical cocktail of valproic acid, CHIR99021, and Repsox(VCR) promotes mouse fibroblasts to differentiate into NPCs under hypoxic conditions. Therefore, we used VCR(0.5 mM valproic acid, 3 μM CHIR99021, and 1 μM Repsox) to induce the reprogramming of rat embryonic fibroblasts into NPCs under a hypoxic condition(5%). These NPCs exhibited typical neurosphere-like structures that can express NPC markers, such as Nestin, SRY-box transcription factor 2, and paired box 6(Pax6), and could also differentiate into multiple types of functional neurons and astrocytes in vitro. They had similar gene expression profiles to those of rat brain-derived neural stem cells. Subsequently, the chemically-induced NPCs(ciNPCs) were stereotactically transplanted into the substantia nigra of 6-hydroxydopamine-lesioned parkinsonian rats. We found that the ciNPCs exhibited long-term survival, migrated long distances, and differentiated into multiple types of functional neurons and glial cells in vivo. Moreover, the parkinsonian behavioral defects of the parkinsonian model rats grafted with ciNPCs showed remarkable functional recovery. These findings suggest that rat fibroblasts can be directly transformed into NPCs using a chemical cocktail of VCR without introducing exogenous factors, which may be an attractive donor material for transplantation therapy for Parkinson’s disease.

关键词： cell reprogramming cell transplantation hypoxia neural progenitor cells neurological function Parkinson’s disease small molecule compounds substantia nigra

Iteration dependent interval based open‐closed‐loop iterative learning control for time varying systems with vector relative degree

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CAAI Transactions on Intelligence Technology 2023年第3期8卷 645-660页

作者： yun‐Shan Wei Jin‐Fan Wang jia‐Xuan Wang Qing‐yuan Xu Jaime Lloret School of Electronics and Communication Engineering Guangzhou UniversityGuangzhouChina School of Electronic and Information Guangdong Polytechnic Normal UniversityGuangzhouChina Universitat Politècnica de València ValenciaSpain

For linear time varying(LTV)multiple input multiple output(MIMO)systems with vector relative degree,an open‐closed‐loop iterative learning control(ILC)strategy is developed in this article,where the time interval of operation is iteration dependent.To compensate the missing tracking signal caused by iteration dependent interval,the feedback control is introduced in ILC design.As the tracking signal of many continuous iterations is lost in a certain interval,the feedback control part can employ the tracking signal of current iteration for compensation.Under the assumption that the initial state vibrates around the desired initial state uniformly in mathematical expectation sense,the expectation of ILC tracking error can converge to zero as the number of iteration tends to infinity.Under the circumstance that the initial state varies around the desired initial state with a bound,as the number of iteration tends to infinity,the expectation of ILC tracking error can be driven to a bounded range,whose upper bound is proportional to the fluctuation.It is revealed that the convergence condition is dependent on the feed-forward control gains,while the feedback control can accelerate convergence speed by selecting appropriate feedback control gains.As a special case,the controlled system with integrated high relative degree is also addressed by proposing a simplified iteration dependent interval based open‐closed‐loop ILC method.Finally,the effectiveness of the developed iteration dependent interval based open‐closed‐loop ILC is illustrated by a simulation example with two cases on initial state.

关键词： intelligent control iterative methods

A non-invasive diagnostic method of cavity detuning based on a convolutional neural network

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Nuclear Science and Techniques 2022年第7期33卷 25-35页

作者： Liu-yuan Zhou Hao Zha jia-Ru Shi jia-Qi Qiu Chuan-Jing Wang yun-Sheng Han Huai-Bi Chen Department of Engineering Physics Tsinghua UniversityBeijing100084China Key Laboratory of Particle and Radiation Imaging Tsinghua UniversityBeijing100084China

As modern accelerator technologies advance toward more compact sizes,conventional invasive diagnostic methods of cavity detuning introduce negligible interference in measurements and run the risk of harming structural surfaces.To overcome these difficulties,this study developed a non-invasive diagnostic method using knowledge of scattering parameters with a convolutional neural network and the interior point method.Meticulous construction and training of the neural network led to remarkable results on three typical acceleration structures:a 13-cell S-band standing-wave linac,a 12-cell X-band traveling-wave linac,and a 3-cell X-band RF gun.The trained networks significantly reduced the burden of the tuning process,freed researchers from tedious tuning tasks,and provided a new perspective for the tuning of side-coupling,semi-enclosed,and total-enclosed structures.

关键词： Cavity detuning Convolutional neural network Equivalent circuit

Application of ultrasound contrast in identification and diagnosis of ocular spaceoccupying lesions

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International Journal of Ophthalmology(English edition) 2011年第4期4卷 337-342页

作者： jia-Ying yuan, yun-Tao Zhang Department of Ultrasonography Hospital of Military Area of He'nan Zhengzhou 450003 He'nan Province China The Faculty of Biomedical Engineering of Zhengzhou University Zhengzhou 450001 He'nan Province China Department of Ultrasonography Xi'an Electricity Hospital Xi'an 710032 Shaanxi Province China Department of Urology Surgery Xijing Hospital the Fourth Military Medical University Xìan 710032 Shaanxi Province China

AIM: To analyze the application significance of ultrasound contrast agent in identification and diagnosis of ocular spaceoccupying lesions, and mainly analyze its advantages and problems. METHODS: Thirty-two representative literatures about the application of ultrasound contrast agent in diagnosis of spaceoccupying lesions at home and abroad were collected after focused on sorting the literature reporting the application of ultrasound contrast diagnostic technology in the diagnosis and identification of ocular spaceoccupying lesions in recent years. Its advantages and problems were retrospectively analyzed, and reasonable assessment on Existing problems was made and possible solutions to the problems were proposed. RESULTS: As a new imaging diagnostic technique, the contrast-enhanced ultrasound, which can enhance the display of tumor microcirculation vessels and improve the tumor's ultrasound diagnostic capability, was analyzed. Through sorting and comprehensively analyzing the collected literatures, the positive rate of ocular spaceoccupying lesion diagnosis could be significantly improved with ultrasound contrast technology. Thus, the vascular perfusion in normal tissues and lesions was reflected objectively. According to the lesion's perfusion characteristics of the contrast agent plus with the performance features of two-dimensional ultrasound, the ocular spaceoccupying lesions can be accurately diagnosed, and this could provide clinicians with reliable research basis in this field. CONCLUSION: Ultrasound contrast examination is a new testing method, and ultrasound contrast agent can significantly enhance the ultrasonic detection signal, clearly show the blood perfusion in vessels and tissues, increase the image contrast resolution, and improve the lesion's detection capability in the microcirculation perfusion level, especially its important value in the diagnosis of ocular tumor.

关键词： ultrasound contrast ocular spaceoccupying lesion differential diagnosis new microbubble contrast agent

Mills’syndrome is a unique entity of upper motor neuron disease with N-shaped progression:Three case reports

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World Journal of Clinical Cases 2022年第19期10卷 6664-6671页

作者： Zhi-yun Zhang Zhi-yuan Ouyang Guo-Hua Zhao jia-jia Fang Department of Neurology The Fourth Affiliated HospitalZhejiang University School of MedicineYiwu 322000Zhejiang ProvinceChina Department of Neurology The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310000Zhejiang ProvinceChina

BACKGROUND Mills’syndrome is an extremely rare degenerative motor neuron disorder first described by Mills in 1900,but its nosological status is still not clear.We aimed to analyze the clinical features of Mills’syndrome.CASE SUMMARY Herein,we present 3 cases with similar features as those described in Mills’original paper and review the related literature.Our patients showed middle-and older-age onset,with only upper motor neuron symptoms evident throughout the course of the disease.Spastic hemiplegia began in the lower extremity with a unique progressive pattern.CONCLUSION We consider that Mills’syndrome is a unique entity of motor neuron disorder with an N-shaped progression.Clinicians should maintain a high index of suspicion for the diagnosis of Mills’syndrome when the onset involves lower extremity paralysis without evidence of lower motor neuron or sensory involvement.

关键词： Mills’syndrome Motor neuron disease Primary lateral sclerosis Amyotrophic lateral sclerosis N-shaped progression Case report

The rLrp of Mycobacterium tuberculosis inhibits proinflammatory cytokine production and downregulates APC function in mouse macrophages via a TLR2-mediated PI3K/Akt pathway activation-dependent mechanism

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Cellular & Molecular Immunology 2016年第6期13卷 729-746页

作者： yuan Liu jia-yun Li Su-Ting Chen Hai-Rong Huang Hong Cai State Key Laboratory of Protein and Plant Gene Research College of Life Sciences Peking University Beijing 100871 China National Clinical Laboratory on Tuberculosis Beijing Key Laboratory on Drug-Resistant Tuberculosis Research Beijing Chest Hospital Capital Medical University Beijing Tuberculosis and Thoracic Tumor Institute Beijing 101149 China

We demonstrate that Mycobacterium tuberculosis recombinant leucine-responsive regulatory protein （rLrp） inhibits lipopolysaccharide （LPS）-induced tumor necrosis factor alpha （TNF-a）, interleukin-6, and interleukin-12 production and blocks the nuclear translocation of subunits of the nuclear-receptor transcription factor NF-KB （Nuclear factor-kappa B）. Moreover, rLrp attenuated LPS-induced DNA binding and NF-κB transcriptional activity, which was accompanied by the degradation of inhibitory IκBα and a consequent decrease in the nuclear translocation of the NF-κB p65 subunit. RLrp interfered with the LPS-induced clustering of TNF receptor-associated factor 6 and with interleukin-1 receptor-associated kinase 1 binding to TAKI. Furthermore, rLrp did not attenuate proinflammatory cytokines or the expression of CD86 and major histocompatibility complex class-II induced by interferon-gamma in the macrophages of Toll-like receptor 2 deletion （TLR2-/-） mice and in protein kinase b （Akt）-depleted mouse cells, indicating that the inhibitory effects of rLrp were dependent on TLR2-mediated activation of the phosphatidylinositol 3-OH kinase （PI3K）/ Akt pathway. RLrp could also activate the PI3K/Akt pathway by stimulating the rapid phosphorylation of PI3K, Akt, and glycogen synthase kinase 3 beta in macrophages. In addition, 19 amino acid residues in the N-terminus of rLrp were determined to be important and required for the inhibitory effects mediated by TLR2. The inhibitory function of these 19 amino acids of rLrp raises the possibility that mimetic inhibitory peptides could be used to restrict innate immune responses in situations in which prolonged TLR signaling has deleterious effects. Our study offers new insight into the inhibitory mechanisms by which the TLR2-mediated PI3K/Akt pathway ensures the transient expression of potent inflammatory mediators.

关键词： APC function cytokine Mycobacterium tuberculosis rLrp TLR2 and PI3 K/Akt pathway