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The role of tyrosine phosphatase Shp2 in spermatogonial differentiation and spermatocyte meiosis

Asian Journal of Andrology 2020年第1期22卷 79-87页

作者： Yang Li Wen-Sheng Liu Jia Yi Shuang-Bo Kong Jian-Cheng Ding Yi-Nan Zhao ying-pu tian Gen-Sheng Feng Chao-Jun Li Wen Liu Hai-Bin Wang Zhong-Xian Lu School of Pharmaceutical Sciences State Key Laboratory of Cellular Stress BiologyXiamen UniversityXiamen 361005China Fujian Provincial Key Laboratory of Reproductive Health Research Medical College of Xiamen UniversityXiamen 361005China Fujian Provincial Key Laboratory of Innovative Drug Target Research School of Pharmaceutical SciencesXiamen 361005China Department of Pathology Division of Biological SciencesUniversity of California at San DiegoLa JollaCA 92093USA Ministry of Education Key Laboratory of Model Animals for Disease Study Model Animal Research Center and Medical School of Nanjing UniversityNational Resource Center for Mutant MiceNanjing 210061China

The transition from spermatogonia to spermatocytes and the initiation of meiosis are key steps in spermatogenesis and are precisely regulated by a plethora of proteins.However,the underlying molecular mechanism remains largely unknown.Here,we report that Src homology domain tyrosine phosphatase 2(Shp2;encoded by the protein tyrosine phosphatase,nonreceptor type 11[Ptpn11]gene)is abundant in spermatogonia but markedly decreases in meiotic spermatocytes.Conditional knockout of Shp2 in spermatogonia in mice using stimulated by retinoic acid gene 8(Stra8)-cre enhanced spermatogonial differentiation and disturbed the meiotic process.Depletion of Shp2 in spermatogonia caused many meiotic spermatocytes to die;moreover,the surviving spermatocytes reached the leptotene stage early at postnatal day 9(PN9)and the pachytene stage at PN11-13.In preleptotene spermatocytes,Shp2 deletion disrupted the expression of meiotic genes,such as disrupted meiotic cDNA 1(Dmc1),DNA repair recombinase rad51(Rad51),and structural maintenance of chromosome 3(Smc3),and these deficiencies interrupted spermatocyte meiosis.In GC-1 cells cultured in vitro,Shp2 knockdown suppressed the retinoic acid(RA)-induced phosphorylation of extracellular-regulated protein kinase(Erk)and protein kinase B(Akt/PKB)and the expression of target genes such as synaptonemal complex protein 3(Sycp3)and Dmc1.Together,these data suggest that Shp2 plays a crucial role in spermatogenesis by governing the transition from spermatogonia to spermatocytes and by mediating meiotic progression through regulating gene transcription,thus providing a potential treatment target for male infertility.

关键词： cell differentiation gene expression spermatogenesis transgenic mouse

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Revealing the anti-sintering phenomenon on silica-supported nickel catalysts during CO_(2)hydrogenation

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Journal of Environmental Sciences 2024年第6期140卷 270-278页

作者： Liuqingqing Yang tiancheng pu Feixiang tian Yulian He Minghui Zhu State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China University of Michigan-Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong UniversityShanghai 200240China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

The CO_(2)catalytic hydrogenation represents a promising approach for gas-phase CO_(2)utilization in a direct manner.Due to its excellent hydrogenation ability,nickel has been widely studied and has shown good activities in CO_(2)hydrogenation reactions,in addition to its high availability and low price.However,Ni-based catalysts are prone to sintering under elevated temperatures,leading to unstable catalytic performance.In the present study,various characterization techniques were employed to study the structural evolution of Ni/SiO_(2)during CO_(2)hydrogenation.An anti-sintering phenomenon is observed for both 9%Ni/SiO_(2)and 1%Ni/SiO_(2)during CO_(2)hydrogenation at 400℃.Results revealed that Ni species were re-dispersed into smaller-sized nanoparticles and formed Ni^(0)active species.While interestingly,this anti-sintering phenomenon leads to distinct outcomes for two catalysts,with a gradual increase in both reactivity and CH_(4)selectivity for 9%Ni/SiO_(2)presumably due to the formation of abundant surface Ni°from redispersion,while an apparent decreasing trend of CH_(4)selectivity for 1%Ni/SiO_(2)sample,presumably due to the formation of ultra-small nanoparticles that diffuse and partially filled the mesoporous pores of the silica support over time.Finally,the redispersion phenomenon was found relevant to the H_(2)gas in the reaction environment and enhanced as the H_(2)concentration increased.This finding is believed to provide in-depth insights into the structural evolution of Ni-based catalysts and product selectivity control in CO_(2)hydrogenation reactions.

关键词： Carbon dioxide utilization CO_(2)hydrogenation Nickel-based catalysts Anti-sintering Structural evolution

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New method for multibody dynamics based on unknown constraint force

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Science China(Technological Sciences) 2024年第3期67卷 791-808页

作者： tian ying JIA yingHong ZHANG Jun School of Astronautics Beihang UniversityBeijing 100191China Beijing Institute of Control Engineering Beijing 100190China National Laboratory of Space Intelligent Control Beijing 100190China

This paper presents a new method for the dynamics of multibody systems based on unknown constraint force. The method can uniformly solve multibody systems with typical configurations, including the system with rigid-flexible coupling, the system in tree topology, and the system with loop constraints. Unlike common methods, the proposed method can model the loop system without “cutting off” loop constraints, leading to the exact same modelling process as the tree-like system performs. Based on graph theory, a topological record matrix M_(rec) is proposed to capture the arbitrary system configuration. Moreover, constraint forces are selected as the key variables in semi-recursive framework. With the recursive kinematics relationship between adjacent bodies, the constraint force equation is further assembled to achieve the full-state system solution. The numerical simulations demonstrate the accuracy of the proposed method.

关键词： multibody system dynamic modelling rigid-flexible coupling unknown constraint force graph theory semi-recursive algorithm

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Resilience provides mediating effect of resilience between fear of progression and sleep quality in patients with hematological malignancies

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World Journal of Psychiatry 2024年第4期14卷 541-552页

作者： Yuan tian ying-Li Wang Department of Hematology The First Affiliated Hospital of Jinzhou Medical UniversityJinzhou 121000Liaoning ProvinceChina Department of Cardiology The First Affiliated Hospital of Jinzhou Medical UniversityJinzhou 121000Liaoning ProvinceChina

BACKGROUND Hematological tumors are common malignant tumors,with high morbidity and mortality rates.Most patients with hematological malignancies develop sleep disorders that seriously affect their life and health because of acute onset of disease,rapid progression,high recurrence rates,complex treatment methods,and treatment costs.AIM To explore the mediating effect of resilience on fear of disease progression and sleep quality in patients with hematological malignancies.METHODS A cross-sectional analysis of 100 patients with hematological malignancies,treated in the First Affiliated Hospital of Jinzhou Medical University between August 2022 and August 2023,was conducted.Patients were assessed using a general data survey,a simplified scale for the fear of progression(FoP)of disease,a resilience scale,and the Pittsburgh Sleep Quality Index.Statistical analysis was conducted to determine the relationship between various patient characteristics and FoP,resilience,and sleep quality.Spearman’s correlation analysis was used to examine the correlations between mental resilience,FoP,and sleep quality.RESULTS The total FoP score mean value in patients with hematological malignancies was 38.09±5.16;the total resilience score mean value was 40.73±7.04;and the Pittsburgh Sleep Quality Index score mean value was 10.72±1.90.FoP,resilience,and sleep quality of the patients were associated with family per capita monthly income and patient education level(P<0.05).Spearman correlation analysis revealed that FoP was negatively correlated with resilience and sleep quality scores(r=-0.560,-0.537,P<0.01),respectively,and resilience was significantly associated with sleep quality scores(r=0.688,P<0.01).Mediation analysis showed that the mediating effect of resilience between FoP and sleep quality in patients with hematological malignancies was-0.100 and accounted for 50.51%of the total effect.This indicated that FoP directly and indirectly affected sleep quality through the mesomeric effect of resilience.CONCLUSION Resilience is an in

关键词： Resilience Blood tumor Fear of progression Sleep quality Mediating effect

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Experimental Study on Towing Characteristics of Composite Bucket Wellhead Platform

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China Ocean Engineering 2024年第3期38卷 531-542页

作者： ZHANG pu-yang LIU ying-fei LE Cong-huan DING Hong-yan BAI Yu State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China

With the rapid development of large-scale development of marginal oilfields in China,simple wellhead platforms that are simple in structure and easy to install have become an inevitable choice in the process of oilfield development.However,traditional simple wellhead platforms are often discarded after a single use.In pursuit of a more costeffective approach to developing marginal oilfields,this paper proposes a new offshore oil field development facility—an integrated bucket foundation for wellhead platform.To verify the safety of its towing behavior and obtain the dynamic response characteristics of the structure,this paper takes a bucket integrated bucket foundation for wellhead platform with a diameter of 40 m as the research object.By combining physical model tests and numerical simulations,it analyzes the static stability and dynamic response characteristics of the structure during towing,complete with the effects of the draft,wave height,wave period,and towing point height,which produce the dynamic responses of the structure under different influence factors,such as roll angle,pitch angle,heave acceleration and towing force as well as the sensibility to transport variables.The results show that the integrated bucket foundation for wellhead platform is capable of self-floating towing,and its movement is affected by the local environment,which will provide a reference for actual projects.

关键词： composite bucket foundation wellhead platform air flotation towing model test

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Computed tomography-based radiomics diagnostic approach for differential diagnosis between early-and late-stage pancreatic ductal adenocarcinoma

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1256-1267页

作者： Shuai Ren Li-Chao Qian ying-ying Cao Marcus J Daniels Li-Na Song ying tian Zhong-Qiu Wang Department of Radiology Jiangsu Province Hospital of Chinese MedicineAffiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Geratology Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese MedicineNanjing 210022Jiangsu ProvinceChina Department of Radiology NYU Langone HealthNew YorkNY 10016United States

BACKGROUND One of the primary reasons for the dismal survival rates in pancreatic ductal adenocarcinoma(PDAC)is that most patients are usually diagnosed at late stages.There is an urgent unmet clinical need to identify and develop diagnostic methods that could precisely detect PDAC at its earliest stages.METHODS A total of 71 patients with pathologically proved PDAC based on surgical resection who underwent contrast-enhanced computed tomography(CT)within 30 d prior to surgery were included in the study.Tumor staging was performed in accordance with the 8th edition of the American Joint Committee on Cancer staging system.Radiomics features were extracted from the region of interest(ROI)for each patient using Analysis Kit software.The most important and predictive radiomics features were selected using Mann-Whitney U test,univar-iate logistic regression analysis,and minimum redundancy maximum relevance(MRMR)method.Random forest(RF)method was used to construct the radiomics model,and 10-times leave group out cross-validation(LGOCV)method was used to validate the robustness and reproducibility of the model.RESULTS A total of 792 radiomics features(396 from late arterial phase and 396 from portal venous phase)were extracted from the ROI for each patient using Analysis Kit software.Nine most important and predictive features were selected using Mann-Whitney U test,univariate logistic regression analysis,and MRMR method.RF method was used to construct the radiomics model with the nine most predictive radiomics features,which showed a high discriminative ability with 97.7%accuracy,97.6%sensitivity,97.8%specificity,98.4%positive predictive value,and 96.8%negative predictive value.The radiomics model was proved to be robust and reproducible using 10-times LGOCV method with an average area under the curve of 0.75 by the average performance of the 10 newly built models.CONCLUSION The radiomics model based on CT could serve as a promising non-invasive method in differential diagnosis between early and late stage PDAC.

关键词： Pancreatic ductal adenocarcinoma Radiomics Computed tomography American Joint Committee on Cancer staging

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Research on aiming methods for small sample size shooting tests of two-dimensional trajectory correction fuse

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Defence Technology（防务技术） 2024年第3期33卷 506-517页

作者： Chen Liang Qiang Shen Zilong Deng Hongyun Li Wenyang pu Lingyun tian Ziyang Lin School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

The longitudinal dispersion of the projectile in shooting tests of two-dimensional trajectory corrections fused with fixed canards is extremely large that it sometimes exceeds the correction ability of the correction fuse actuator.The impact point easily deviates from the target,and thus the correction result cannot be readily evaluated.However,the cost of shooting tests is considerably high to conduct many tests for data collection.To address this issue,this study proposes an aiming method for shooting tests based on small sample size.The proposed method uses the Bootstrap method to expand the test data;repeatedly iterates and corrects the position of the simulated theoretical impact points through an improved compatibility test method;and dynamically adjusts the weight of the prior distribution of simulation results based on Kullback-Leibler divergence,which to some extent avoids the real data being"submerged"by the simulation data and achieves the fusion Bayesian estimation of the dispersion center.The experimental results show that when the simulation accuracy is sufficiently high,the proposed method yields a smaller mean-square deviation in estimating the dispersion center and higher shooting accuracy than those of the three comparison methods,which is more conducive to reflecting the effect of the control algorithm and facilitating test personnel to iterate their proposed structures and algorithms.;in addition,this study provides a knowledge base for further comprehensive studies in the future.

关键词： Two-dimensional trajectory correction fuse Small sample size test Compatibility test KL divergence Fusion bayesian estimation

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Biochemistry and transcriptome analysis reveal condensed tannins alleviate liver injury induced by regulating cholesterol metabolism pathway

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Food Science and Human Wellness 2024年第2期13卷 909-919页

作者： Xiangxin Li Yijing pu Bangdi Liu Xiaoming Fang Wenjun Peng Weibo Jiang Wenli tian Institute of Apicultural Research Chinese Academy of Agricultural SciencesBeijing 100093China College of Food Science and Nutritional Engineering China Agricultural UniversityBeijing 100083China Academy of Agricultural Planning and Engineering Ministry of Agriculture and Rural AffairsBeijing 100125China

Free cholesterol has been considered to be a critical risk factor of nonalcoholic fatty liver disease(NAFLD).It remains unknown whether dietary intake of condensed tannins(CTs)have distinguishable effects to alleviate liver damage caused by a high cholesterol diet.Male C57BL/6 mice were fed a high cholesterol diet for 6 weeks,and given CTs treatment at a dosage of 200 mg/(kg·day)at the same time.The results indicated that compared with mice fed a normal diet,a high cholesterol diet group resulted in significant weight loss,dysregulation of lipid metabolism in blood and liver,and oxidative stress in the liver,but CTs treatment dramatically reversed these negative effects.Hematoxylin and eosin(H&E)staining and frozen section observation manifested that CTs treatment could effectively reduce the deposition of liver cholesterol and tissue necrosis caused by high cholesterol intake.CTs alleviated liver injury mainly by regulating the expression of related genes in cholesterol metabolism pathway and AMPK phosphorylation.Our results confirmed that CTs have remarkable cholesterol lowering and anti-liver injury effects in vivo.

关键词： Condensed tannins High cholesterol Liver injury Antioxidants Transcriptomic analysis

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αDecay in extreme laser fields within a deformed Gamow-like model

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Nuclear Science and Techniques 2024年第2期35卷 131-144页

作者： Qiong Xiao Jun-Hao Cheng Yang-Yang Xu You-tian Zou Jun-Gang Deng Tong-pu Yu Department of Physics National University of Defense TechnologyChangsha 410073China College of Science China Three Gorges UniversityYichang 443002China

In this study, the effect of extreme laser fields on the α decay process of ground-state even–even nuclei was investigated.Using the deformed Gamow-like model, we found that state-of-the-art lasers can cause a slight change in the α decay penetration probability of most nuclei. In addition, we studied the correlation between the rate of change of the α decay penetration probability and angle between the directions of the laser electric field and α particle emission for different nuclei. Based on this correlation, the average effect of extreme laser fields on the half-life of many nuclei with arbitrary α particle emission angles was calculated. The calculations show that the laser suppression and promotion effects on the α decay penetration probability of the nuclei population with completely random α particle-emission directions are not completely canceled.The remainder led to a change in the average penetration probability of the nuclei. Furthermore, the possibility of achieving a higher average rate of change by altering the spatial shape of the laser is explored. We conclude that circularly polarized lasers may be helpful in future experiments to achieve a more significant average rate of change of the α decay half-life of the nuclei population.

关键词： αDecay Deformed Gamow-like model Half-lives Extreme laser field Penetration probability

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Elemene Antitumor Drugs Development Based on "Molecular Compatibility Theory" and Clinical Application: A Retrospective and Prospective Outlook

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Chinese Journal of Integrative Medicine 2024年第1期30卷 62-74页

作者： JIANG Xiao-ying SHI Li-ping ZHU Jun-long BAI Ren-ren XIE tian School of Pharmacy Hangzhou Normal UniversityHangzhou(311121)China Key Laboratory of Elemene Class Anti-cancer Chinese Medicines Engineering Laboratory of Development and Application of Traditional Chinese MedicinesCollaborative Innovation Center of Traditional Chinese Medicines of Zhejiang ProvinceHangzhou Normal UniversityHangzhou(311121)China Good Clinical Practice Center Affliliated Hospital of Nanjing University of Chinese MedicineNanjing(210000)China

Elemene, derived from Curcuma wenyujin, one of the "8 famous genuine medicinal materials of Zhejiang province," exhibits remarkable antitumor activity. It has gained wide recognition in clinical practice for effectiveness on tumors. Dr. XIE tian introduced the innovative concept of "molecular compatibility theory" by combining Chinese medicine principles, specifically the "monarch, minister, assistant, and envoy" theory, with modern biomedical technology. This groundbreaking approach, along with a systematic analysis of Chinese medicine and modern biomedical knowledge, led to the development of elemene nanoliposome formulations. These novel formulations offer numerous advantages, including low toxicity, well-defined composition, synergistic effects on multiple targets, and excellent biocompatibility. Following the principles of the "molecular compatibility theory", further exploration of cancer treatment strategies and methods based on elemene was undertaken. This comprehensive review consolidates the current understanding of elemene's potential antitumor mechanisms, recent clinical investigations, advancements in drug delivery systems, and structural modifications. The ultimate goal of this review is to establish a solid theoretical foundation for researchers, empowering them to develop more effective antitumor drugs based on the principles of "molecular compatibility theory".

关键词： molecular compatibility theory Chinese integrative medicine elemene antitumor activity drug delivery structural modification

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