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Theory and classification of mass extinction causation

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National Science Review 2024年第1期11卷 16-36页

作者： Thomas J.Algeo jun shen State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences—Wuhan State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences—Wuhan Department of Geosciences University of Cincinnati

Theory regarding the causation of mass extinctions is in need of systematization, which is the focus of this contribution. Every mass extinction has both an ultimate cause, i.e. the trigger that leads to various climato-environmental changes, and one or more proximate cause(s), i.e. the specific climato-environmental changes that result in elevated biotic mortality. With regard to ultimate causes, strong cases can be made that bolide(i.e. meteor) impacts, large igneous province(LIP) eruptions and bioevolutionary events have each triggered one or more of the Phanerozoic Big Five mass extinctions, and that tectono-oceanic changes have triggered some second-order extinction events. Apart from bolide impacts, other astronomical triggers(e.***.solar flares, gamma bursts and supernova explosions) remain entirely in the realm of speculation. With regard to proximate mechanisms, most extinctions are related to either carbon-release or carbon-burial processes, the former being associated with climatic warming, ocean acidification, reduced marine productivity and lower carbonate δ13C values, and the latter with climatic cooling, increased marine productivity and higher carbonate δ13C values. Environmental parameters such as marine redox conditions and terrestrial weathering intensity do not show consistent relationships with carbon-cycle changes.In this context, mass extinction causation can be usefully classified using a matrix of ultimate and proximate factors. Among the Big Five mass extinctions, the end-Cretaceous biocrisis is an example of a bolide-triggered carbon-release event, the end-Permian and end-Triassic biocrises are examples of LIP-triggered carbon-release events, and the Late Ordovician and Late Devonian biocrises are examples of bioevolution-triggered carbon-burial events. Whereas the bolide-impact and LIP-eruption mechanisms appear to invariably cause carbon release, bioevolutionary triggers can result in variable carbon-cycle changes, e.g. carbon burial during the Late Ordovician and Late Devonian events,

关键词： biocrisis ultimate cause proximate cause bolide large igneous province bioevolutionary event

Mechanism of microarc oxidation on AZ91D Mg alloy induced byβ-Mg_(17)Al_(12) phase

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 712-724页

作者： Dajun Zhai Xiaoping Li jun shen College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

This work proposed a strategy of indirectly inducing uniform microarc discharge by controlling the content and distribution ofβ-Mg_(17)Al_(12)phase in AZ91D Mg alloy.Two kinds of nano-particles(ZrO_(2)and TiO_(2))were designed to be added into the substrate of Mg alloy by friction stir processing(FSP).Then,Mg alloy sample designed with different precipitated morphology ofβ-Mg_(17)Al_(12)phase was treated by microarc oxidation(MAO)in Na_(3)PO_(4)/Na2SiO3electrolyte.The characteristics and performance of the MAO coating was analyzed using scanning electron microscopy(SEM),energy dispersive spectrometer(EDS),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),contact angle meter,and potentiodynamic polarization.It was found that the coarseα-Mg grains in extruded AZ91D Mg alloy were refined by FSP,and theβ-Mg_(17)Al_(12)phase with reticular structure was broken and dispersed.The nano-ZrO_(2)particles were pinned at the grain boundary by FSP,which refined theα-Mg grain and promoted the precipitation ofβ-Mg_(17)Al_(12)phase in grains.It effectively inhibited the“cascade”phenomenon of microarcs,which induced the uniform distribution of discharge pores.The MAO coating on Zr-FSP sample had good wettability and corrosion resistance.However,TiO_(2)particles were hardly detected in the coating on TiFSP sample.

关键词： AZ91D Mg alloy microarc oxidation friction stir processing ZrO_(2) TiO_(2) β-Mg_(17)Al_(12)

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Advances in MET tyrosine kinase inhibitors in gastric cancer

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Cancer Biology & Medicine 2024年第6期21卷 484-498页

作者： Yifan Zhang lin shen Zhi Peng Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) Department of Gastrointestinal Oncology Peking University Cancer Hospital & Institute State Key Laboratory of Holistic Integrative Management of Gastrointestinal Cancers Beijing Key Laboratory of Carcinogenesis and Translational Research Department of Gastrointestinal Oncology Peking University Cancer Hospital & Institute

Gastric cancer is among the most frequently occurring cancers and a leading cause of cancer-related deaths globally. Because gastric cancer is highly heterogenous and comprised of different subtypes with distinct molecular and clinical characteristics, the management of gastric cancer calls for better-defined, biomarker-guided, molecular-based treatment strategies. MET is a receptor tyrosine kinase mediating important physiologic processes, such as embryogenesis, tissue regeneration, and wound healing. However, mounting evidence suggests that aberrant MET pathway activation contributes to tumour proliferation and metastasis in multiple cancer types, including gastric cancer, and is associated with poor patient outcomes. As such, MET-targeting therapies are being actively developed and promising progress has been demonstrated, especially with MET tyrosine kinase inhibitors. This review aims to briefly introduce the role of MET alterations in gastric cancer and summarize in detail the current progress of MET tyrosine kinase inhibitors in this disease area with a focus on savolitinib, tepotinib, capmatinib, and crizotinib. Building on current knowledge, this review further discusses existing challenges in MET alterations testing, possible resistance mechanisms to MET inhibitors, and future directions of MET-targeting therapies.

关键词： Gastric cancer MET alterations MET testing MET tyrosine kinase inhibitors savolitinib

Ubiquitin-specific protease 21 promotes tumorigenicity and stemness of colorectal cancer by deubiquitinating and stabilizing ZEB1

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 1006-1018页

作者： jun-jun lin Ye-Cai Lu Department of Gastrointestinal Surgery Chaohu Hospital of Anhui Medical UniversityChaohu 238000Anhui ProvinceChina

BACKGROUND Colorectal cancer(CRC)is one very usual tumor together with higher death rate.Ubiquitin-specific protease 21(USP21)has been confirmed to take part into the regulation of CRC progression through serving as a facilitator.Interestingly,the promotive function of USP21 has also discovered in the progression of CRC.ZEB1 has illustrated to be modulated by USP7,USP22 and USP51 in cancers.However,the regulatory functions of USP21 on ZEB1 in CRC progression need more invest-igations.AIM To investigate the relationship between USP21 and ZEB1 in CRC progression.METHODS The mRNA and protein expressions were assessed through RT-qPCR,western blot and IHC assay.The interaction between USP21 and ZEB1 was evaluated through Co-IP and GST pull down assays.The cell proliferation was detected through colony formation assay.The cell migration and invasion abilities were determined through Transwell assay.The stemness was tested through sphere formation assay.The tumor growth was evaluated through in vivo mice assay.RESULTS In this work,USP21 and ZEB1 exhibited higher expression in CRC,and resulted into poor prognosis.Moreover,the interaction between USP21 and ZEB1 was further investigated.It was demonstrated that USP21 contributed to the stability of ZEB1 through modulating ubiquitination level.In addition,USP21 streng-thened cell proliferation,migration and stemness through regulating ZEB1.At last,through in vivo assays,it was illustrated that USP21/ZEB1 axis aggravated tumor growth.CONCLUSION For the first time,these above findings manifested that USP21 promoted tumorigenicity and stemness of CRC by deubiquitinating and stabilizing ZEB1.This discovery suggested that USP21/ZEB1 axis may provide novel sights for the treatment of CRC.

关键词： Ubiquitin-specific protease 21 ZEB1 Stemness Colorectal cancer

Biotic and abiotic stresses on honeybee health

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Integrative Zoology 2024年第3期19卷 442-457页

作者： Zheguang lin Siyi shen Kang WANG Ting JI Apicultural Research Institute College of Animal Science and TechnologyYangzhou UniversityYangzhouChina

Honeybees are the most critical pollinators providing key ecosystem services that underpin crop production and sustainable agriculture.Amidst a backdrop of rapid global change,this eusocial insect encounters a succession of stressors during nesting,foraging,and pollination.Ectoparasitic mites,together with vectored viruses,have been recognized as central biotic threats to honeybee health,while the spread of invasive giant hornets and small hive beetles also increasingly threatens colonies worldwide.Cocktails of agrochemicals,including acaricides used for mite treatment,and other pollutants of the environment have been widely documented to affect bee health in various ways.Additionally,expanding urbanization,climate change,and agricultural intensification often result in the destruction or fragmentation of flower-rich bee habitats.The anthropogenic pressures exerted by beekeeping management practices affect the natural selection and evolution of honeybees,and colony translocations facilitate alien species invasion and disease transmission.In this review,the multiple biotic and abiotic threats and their interactions that potentially undermine bee colony health are discussed,while taking into consideration the sensitivity,large foraging area,dense network among related nestmates,and social behaviors of honeybees.

关键词： abiotic stressor Apis biotic stressor colony losses interaction effect pollinator decline

Progress on the glassy-crystal laminates:From design,microstructure to deformation and future solutions

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Journal of Materials Science & Technology 2024年第5期172卷 113-144页

作者： Yu Chen Ronggao Cui jun shen Gang Wang College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Department of Motor Design Business Weichai New Energy Technology Co.Ltd.Weifang 261061China Guangdong Key Laboratory of Electromagnetic Control and Intelligent Robots Shenzhen UniversityShenzhen 518060China Laboratory for Microstructures Institute of MaterialsShanghai UniversityShanghai 200444China

The development of new design strategies to create innovative structural materials,refine existing ones,and achieves compatible combinations of strength and plasticity remains a worldwide goal.Promising alloys,such as shape memory alloys(SMAs),bulk metallic glasses(BMGs),high entropy alloys(HEAs),and heterogeneous pure metals such as Cu,have excellent mechanical responses,but they still fall short of meeting all the requirements of structural materials due to specific flaws,such as lack of tensile de-formation for BMGs and low yielding strength for HEAs.To address these shortcomings,proposals such as integrating glassy matrices and crystallized alloys,such as HEAs/SMAs,have been suggested.However,these solutions have unresolved issues,such as the challenging control of B2 phase formation in BMG composites.Recently,glass-crystal(A/C)laminated alloys with alternating layers have been reported to exhibit improved mechanical properties and activated work-hardening behaviors,but they still face press-ing issues such as bonding interfaces and unknown deformation mechanisms.This review focuses on design routes such as the selection of alloy components and processing techniques,exploration of micro-structural evolution and deformation modes with an increase in strain,and future solutions to address pressing and unsolved issues.These prominent advantages include diversified deformation mechanisms,such as deformation twinning,martensitic phase transformation,and precipitation hardening,as well as tuned interactive reactions of shear bands(SBs)near the A/C interfaces.Thus,this review provides a promising pathway to design and develop structural materials in the materials field community.

关键词： Glassy-crystal laminates Bulk metallic glasses High entropy alloys Shape memory alloys Microstructure Deformation mechanisms Future solutions

MicroRNA-298 determines the radio-resistance of colorectal cancer cells by directly targeting human dual-specificity tyrosine(Y)-regulated kinase 1A

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1453-1464页

作者： Mei-Zhu shen Yong Zhang Fang Wu Mei-Zhen shen jun-lin Liang Xiao-Long Zhang Xiao-Jian Liu Xin-Shu Li Ren-sheng Wang Department of Radiotherapy The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina Department of Radiotherapy People’s Hospital of Guangxi Zhuang Autonomous RegionNanning 530021Guangxi Zhuang Autonomous RegionChina Department of Colorectal Anal Surgery The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina Department of Clinical Medicine Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina

BACKGROUND Radiotherapy stands as a promising therapeutic modality for colorectal cancer(CRC);yet,the formidable challenge posed by radio-resistance significantly undermines its efficacy in achieving CRC remission.AIM To elucidate the role played by microRNA-298(miR-298)in CRC radio-resistance.METHODS To establish a radio-resistant CRC cell line,HT-29 cells underwent exposure to 5 gray ionizing radiation that was followed by a 7-d recovery period.The quantification of miR-298 levels within CRC cells was conducted through quantitative RT-PCR,and protein expression determination was realized through Western blotting.Cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and proliferation by clonogenic assay.Radio-induced apoptosis was discerned through flow cytometry analysis.RESULTS We observed a marked upregulation of miR-298 in radio-resistant CRC cells.MiR-298 emerged as a key determinant of cell survival following radiation exposure,as its overexpression led to a notable reduction in radiation-induced apoptosis.Intriguingly,miR-298 expression exhibited a strong correlation with CRC cell viability.Further investigation unveiled human dual-specificity tyrosine(Y)-regulated kinase 1A(DYRK1A)as miR-298’s direct target.CONCLUSION Taken together,our findings underline the role played by miR-298 in bolstering radio-resistance in CRC cells by means of DYRK1A downregulation,thereby positioning miR-298 as a promising candidate for mitigating radioresistance in CRC.

关键词： MicroRNA-298 Human dual-specificity tyrosine(Y)-regulated kinase 1A Colorectal cancer Radio-resistance p53 binding protein 1

Derivatives of Intersection Local Time for Two Independent Symmetricα-stable Processes

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1273-1292页

作者： Huan ZHOU Guang jun shen Qian YU Department of Mathematics Anhui Normal UniversityWuhu 241002P.R.China Department of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China Key Laboratory of Mathematical Modelling and High Performance Computing of Air Vehicles(NUAA) MIITNanjing 211106P.R.China

In this paper,we consider the derivatives of intersection local time for two independent d-dimensional symmetricα-stable processes X^(α) and X^(α)with respective indices α and α.We first study the sufficient condition for the existence of the derivatives,which makes us obtain the exponential integrability and H?lder continuity.Then we show that this condition is also necessary for the existence of derivatives of intersection local time at the origin.Moreover,we also study the power variation of the derivatives.

关键词： Symmetric stable processes intersection local time exponential integrability power variation

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Navigating the complex terrain of hepatitis B virus reactivation in the era of Bruton tyrosine kinase inhibitors

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World Journal of Gastroenterology 2024年第21期30卷 2748-2750页

作者： Wei-Nung Liu Ming-shen Dai Felicia lin Gen-Min lin Department of Medicine Tri-Service General HospitalTaipei 114Taiwan Division of Hematology/Oncology Department of Internal MedicineNational Defense Medical CenterTaipei 114Taiwan Community Care Minnesota OncologyMinneapolisMN 55404United States Department of Medicine Hualien Armed Forces General HospitalHualien City 970Taiwan

In this editorial,we offer a summary of the risk associated with hepatitis B reactivation(HBVr)in the setting of both solid and hematologic malignancies treated with Bruton tyrosine kinase(BTK)inhibitors,with insights derived from current studies.Furthermore,we emphasize the critical need for a framework regarding robust risk evaluation in patients undergoing such treatments.This framework is essential for identifying those at increased risk of HBVr,enabling healthcare providers to implement proactive measures to prevent reactivation and ensure the safe administration of BTK inhibitor therapy.

关键词： Hepatitis B virus reactivation Bruton tyrosine kinase inhibitors Hematologic malignancies Solid tumors Prophylaxis guidelines