The study of the brain and its complex functions is highly fascinating and,at the same time,extremely important.Indeed,furthering our understanding of the biology of neurons and synapses is a prerequisite to uncover t...The study of the brain and its complex functions is highly fascinating and,at the same time,extremely important.Indeed,furthering our understanding of the biology of neurons and synapses is a prerequisite to uncover the mechanisms involved in memory formation and the coordination of movement as well as their alterations occurring in several neurological disorders.展开更多
Abstract The Shibangou gold deposit in western Henan is associated with irregular quartz veinlets occurring in altered shear zones dissecting a dioritic intrusion. The altered shear zones are characterized by silicifi...Abstract The Shibangou gold deposit in western Henan is associated with irregular quartz veinlets occurring in altered shear zones dissecting a dioritic intrusion. The altered shear zones are characterized by silicification, pyritization, sericilization, chloritization and K-feldspar alteration. Zoning of altered rocks adjacent to the Au-bearing quartz veins is obviously exhibited. Fine-grained sulphides and quartz veinlets of different ages and small-scale fissures are widely distributed in the central part of the altered zones. Major mineralization types in this gold deposit are Au-bearing quartz veinlets and altered rocks in the shear zones. Samples were collected from drilling cores according to the alteration zoning and mineralization type and all samples were analyzed for major and trace elements. Mass balance, volume change (fv=97.3–71.9%) and major element variation sequences are studied in terms of major elements. The changes of mobile components (SiO2, K2O, Fe2O3) and CaO) and immobile component (Al2O3) in the wall-rock alteration are discussed. The gold mineralization is associated with the enrichment of As, Ag, Hg and Pb and depletion of Cu and Zn. The study of compositional variation of altered rocks proves to be a very efficient method for defining the extent of wall-rock alteration, fluid activity and mineralization and enrichment.展开更多
Osteoporosis and osteopenia are major health issues that mainly affect elderly people,women after menopause and immobilized patients.Our previous studies have proved that sclerostin antibody(Scl-Ab)can dramatically en...Osteoporosis and osteopenia are major health issues that mainly affect elderly people,women after menopause and immobilized patients.Our previous studies have proved that sclerostin antibody(Scl-Ab)can dramatically enhance bone formation and reduce bone resorption in a severe osteoporosis rat model with the combination of ovariectomy(OVX)and hindlimb immobilization(HLS).However,the mechanism in the cellular level is unclear.The objective of this study is to assess the effect of Scl-Ab on osteocytic morphology change in a combined OVX and HLS rat model via quantification of long-and short-axis and the ratio and osteocyte volume in midshaft cortical bone.Four-month-old virgin female SD rats were divided into 7 groups(n=11 per group):Sham+Veh,Sham+HLS+Veh,Sham+HLS+Scl-Ab,OVX+Veh,OVX+Scl-Ab,OVX+HLS+Veh,OVX+HLS+Scl-Ab.HLS was performed 2 weeks after sham or OVX surgery;and treatment was initiated at the time of HLS.Scl-Ab(25 mg/kg)or vehicle was subcutaneously injected twice per week for 5 weeks.Femurs were harvested at the end of study and embedded in PMMA and polished for SEM imaging.Cortical bone mid shaft osteocyte number per bone area was quantified under 1K magnification;the ratios between long axis and short axis of osteocytes were quantified under 2K magnification;osteocyte dendrite number and surface area were quantified under 5K magnification.Osteocyte dendrites width was quantified using 10K magnification.All the quantification was done by ImageJ.We have reported that multiple morphological and structural changes in osteocytes,including a decreased osteocyte density and reduced osteocyte dendrite number in HLS,OVX or the combination group and Scl-Ab’s ability to abolish these unfavorable alterations.We continued our SEM analysis on osteocytes and discovered that the oval shape of osteocyte under HLS,OVX or HLS+OVX has been distorted toward a spindle-like shape,with relatively longer long axis and shorter short axis,assuming osteocyte has a perfect spheroid shape.The ratio between long-and short-axis showed an increased trend in OVX and HLS condition,but Scl-Ab inhibited these increases(P<0.001,P<0.01,respectively).The volume decreased in HLS,OVX group,but Scl-Ab maintained osteocytes’volume in HLS condition(P<0.001).It indicates that cortical bone responds to HLS and/or OVX and Scl-Ab treatment via multiple cellular mechanisms,including density of osteocyte,dendrite number and osteocyte shape.The change of osteocyte shape may imply an altered cytoskeleton system within osteocyte and a subsequent disruption of mechanosensing ability for osteocyte,which lead to bone loss macroscopically.These data suggest Scl-Ab’s therapeutic potential could be related with its ability to maintain osteocyte’s morphologic and structural changes induced by OVX,HLS or both.展开更多
Solid bitumens were found throughout the carbonate reservoirs in the Puguang gas field, the largest gas field so far found in marine carbonates in China, confirming that the Puguang gas field evolved from a paleo-oil ...Solid bitumens were found throughout the carbonate reservoirs in the Puguang gas field, the largest gas field so far found in marine carbonates in China, confirming that the Puguang gas field evolved from a paleo-oil reservoir. The fluid conduit system at the time of intensive oil accumulation in the field was reconstructed, and petroleum migration pathways were modeled using a 3-D model and traced by geochemical parameters. The forward modeling and inversion tracing coincided with each other and both indicated that oils accumulated in the Puguang-Dongyuezhai structure originated from a generative kitchen to the northwest of the Puguang gas field. The deposition of organic-rich Upper Permian source rocks dominated by sapropelic organic matter in the Northeast Sichuan Basin, the development of fluid conduit system that was vertically near-source rock and laterally near-generative kitchen, and the focusing of oils originated from a large area of the generative kitchen, were the three requirements for the formation of the giant paleo-oil reservoir from which the giant Puguang gas field evolved. The Puguang gas field had experienced a three-stage evolution. The post-accumulation processes, especially the organic-inorganic interaction in the hydrocarbon-water-rock system, had not only profoundly altered the composition and characteristics of the petroleum fluids, but also obviously changed the physicochemical conditions in the reservoir and resulted in complicated precipitation and solution of carbonate minerals.展开更多
Background Non-suicidal self-injury(NSSI)is a frequent and prominent phenomenon in major depressive disorder(MDD).Even though its prevalence and risk factors are relatively well understood,the potential mechanisms of ...Background Non-suicidal self-injury(NSSI)is a frequent and prominent phenomenon in major depressive disorder(MDD).Even though its prevalence and risk factors are relatively well understood,the potential mechanisms of NSSI in MDD remain elusive.Aims To review present evidence related to the potential mechanisms of NSSI in MDD.Methods According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines,articles for this systematic review were searched on Medline(through PubMed),Embase(through Elsevier),PsycINFO(through OVID)and Web of Science databases for English articles,as well as China National Knowledge Infrastructure(CNKI),SinoMed,Wanfang Data,and the Chongqing VIP Chinese Science and Technology Periodical(VIP)Databases for Chinese articles published from the date of inception to 2 August 2022.Two researchers(BW,HZ)independently screened studies based on inclusion and exclusion criteria and assessed their quality.Results A total of 25157 studies were searched.Only 25 of them were ultimately included,containing 3336 subjects(1535 patients with MDD and NSSI,1403 patients with MDD without NSSI and 398 HCs).Included studies were divided into 6 categories:psychosocial factors(11 studies),neuroimaging(8 studies),stress and hypothalamic-pituitary-adrenal(HPA)axis(2 studies),pain perception(1 study),electroencephalogram(EEG)(2 studies)and epigenetics(1 study).Conclusions This systematic review indicates that patients with MDD and NSSI might have specific psychosocial factors,aberrant brain functions and neurochemical metabolisms,HPA axis dysfunctions,abnormal pain perceptions and epigenetic alterations.展开更多
Laser in situ keratomileusis(LASIK)is a relatively new ophthalmic procedure in refractive surgery.It involves the use of a microkeratome to create a thin corneal flap followed by excimer laser ablation of the corneal ...Laser in situ keratomileusis(LASIK)is a relatively new ophthalmic procedure in refractive surgery.It involves the use of a microkeratome to create a thin corneal flap followed by excimer laser ablation of the corneal stroma and repositioning of the flap.However,complications are bound to occur when a surgical procedure is performed with increasing frequency.In some cases,serious complications such as keratectasia occurred.Risk factors for corneal keratectasia include a thin cornea at baseline,thick corneal flap,excessive ablation,irregular corneal thickness,diverse ablation rates,preexisting keratoconus or form fruste keratoconus,and high intraocular pressure(IOP)~[1].It is evident from incisional refractive surgery that the cornea is not mechanically inert.The mechanical environment of the central corneal tissue is also altered un-展开更多
Brass targets were irradiated with various laser pulses of Excimer laser ranging from 1200 to 3000 for constant fluence of 3.4 J/cm2 in oxygen atmosphere (100 Torr). The surface morphology and crystallographic analyse...Brass targets were irradiated with various laser pulses of Excimer laser ranging from 1200 to 3000 for constant fluence of 3.4 J/cm2 in oxygen atmosphere (100 Torr). The surface morphology and crystallographic analyses were performed by using Scanning Electron Microscope (SEM) and X-Ray Diffractometer (XRD). SEM analysis reveals the formation of laser-induced micro-sized cavities, bumps, cones and wave-like ridges with non-uniform shape and density distribution. These features are formed for all number of pulses;however with increasing number of pulses from 1200 to 2400, the density of cavities decreases whereas, the wave-like ridges become more pronounced and bump-formation is vanished. For maximum number of 3000 shots, the appearance of cones and wave-like ridges becomes diffusive, whereas the density and size of cavities increase again. XRD analysis demonstrates that no new phases are formed in irradiated brass. However, the change in peak intensity along with lower and higher angle shifting is observed which is attributed to generation of laser induced stresses. The Yield Stress (YS), Ultimate Tensile Strength (UTS) as well as Microhardness increase monotonically with increasing number of laser pulses.展开更多
Based on analysing the wall rock alterations and related rocks which were used as a hint for mineral deposits and as a basis of mechanism research of fluid rock interaction, according to the results of petrographic an...Based on analysing the wall rock alterations and related rocks which were used as a hint for mineral deposits and as a basis of mechanism research of fluid rock interaction, according to the results of petrographic analysis, the authors of this paper consider that the hydrothermally altered conglomerates have the following features. First, the conglomerates studied can be divided into two groups: Group A consists mainly of the gravels of granite and basalt; Group B is mainly composed of the gravels of basalt, limestone, mudstone and granite. Second, three distinct hydrothermal alterations or diagenesis were distinguished in Group A, that is, pre depositional hydrothermal alteration of the volcanic gravels (saussuritzation chloritization, epidotization chloritization, albitization and sericitization), mechanical diagenesis and post diagenetic hydrothermal alteration (epidote chlorite and prehnite calcite association). Third, the Group B is subjected mainly to pre depositional hydrothermal alteration; the alteration types are the same as of Type A. Last, the origin of the post diagenetic hydrothermal alteration of Group A is presumed to be related to the ascending of thermal water along the Naer Creek fault.展开更多
Tumorigenesis is a multistep process,with oncogenic mutations in a normal cell conferring clonal advantage as the initial event.However,despite pervasive somatic mutations and clonal expansion in normal tissues,their ...Tumorigenesis is a multistep process,with oncogenic mutations in a normal cell conferring clonal advantage as the initial event.However,despite pervasive somatic mutations and clonal expansion in normal tissues,their transformation into cancer remains a rare event,indicating the presence of additional driver events for progression to an irreversible,highly heterogeneous,and invasive lesion.Recently,researchers are emphasizing the mechanisms of environmental tumor risk factors and epigenetic alterations that are profoundly influencing early clonal expansion and malignant evolution,independently of inducing mutations.Additionally,clonal evolution in tumorigenesis reflects a multifaceted interplay between cell-intrinsic identities and various cell-extrinsic factors that exert selective pressures to either restrain uncontrolled proliferation or allow specific clones to progress into tumors.However,the mechanisms by which driver events induce both intrinsic cellular competency and remodel environmental stress to facilitate malignant transformation are not fully understood.In this review,we summarize the genetic,epigenetic,and external driver events,and their effects on the co-evolution of the transformed cells and their ecosystem during tumor initiation and early malignant evolution.A deeper understanding of the earliest molecular events holds promise for translational applications,predicting individuals at high-risk of tumor and developing strategies to intercept malignant transformation.展开更多
The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of Au.This paper presents a new understanding for Dongping ore system,based on the previous studies.The mineralization origi...The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of Au.This paper presents a new understanding for Dongping ore system,based on the previous studies.The mineralization originally occurred at 400-380 Ma,simultaneous with emplacement of the Shuiquangou alkaline complex,and was overprinted by the hydrothermal activity in the Yanshanian.Isotope compositions of ores indicate metals of the deposit are mainly provided by the Shuiquangou complex.Ore-forming fluids are characterized by increasing oxygen fugacity and decreasing sulfur fugacity,while tellurium fugacity increased in the Stage II-2 and decreased in Stage II-3.These systematic changes are closely related to the processes of mineral precipitation and fluid evolution.Sulfide precipitation from Stage Ⅰ to Stage Ⅱ was triggered by fluid boiling,which leads to the precipitation of Pb-Bi-Te,due to decrement of sulfur fugacity.Condensation of gas phase containing high concentration of H_2Te leads to precipitation of Te-Au-Ag minerals and native tellurium.Based on these hypotheses,this paper present a polyphase metallogenic model as follow.During the Devonian,fluids were released from alkaline magmas,which carried ore-forming materials form the surrounding rocks and precipitate the early ores.During the Jurassic-Cretaceous,fluorine-rich fluids exsolved from highly factionated Shangshuiquan granite,which extracted and concentrated Au from the Shuiquangou complex and the Sanggan Group metamorphic rocks,and finally formed the Dongping gold deposit.展开更多
Over the last 30 years,a new actor in the area of ecology and evolution has emerged:niche construction theory(NCT).The fundamental premise of NCT is that organisms may actively influence evolutionary processes by modi...Over the last 30 years,a new actor in the area of ecology and evolution has emerged:niche construction theory(NCT).The fundamental premise of NCT is that organisms may actively influence evolutionary processes by modifying their circumstances[1].According to Trappes et al.,[2]the concept of niche construction should only be applied to species that alter their environment,which they believe to be its intuitive scope.They add two more terms to describe the ways that organisms engage with their surroundings and so influence their niches:when organisms choose their environment,this is known as niche choice,and when they adapt their phenotype to fit their environment,this is known as niche conformance.These three concepts are often referred to as niche-altering mechanisms,or NC3 mechanisms:niche conformance,niche construction,and niche choice.This is in line with definitions of mechanisms developed in scientific philosophy[2].展开更多
基金supported by a grant from the Institut Professeur Baulieu (to DT)。
文摘The study of the brain and its complex functions is highly fascinating and,at the same time,extremely important.Indeed,furthering our understanding of the biology of neurons and synapses is a prerequisite to uncover the mechanisms involved in memory formation and the coordination of movement as well as their alterations occurring in several neurological disorders.
文摘Abstract The Shibangou gold deposit in western Henan is associated with irregular quartz veinlets occurring in altered shear zones dissecting a dioritic intrusion. The altered shear zones are characterized by silicification, pyritization, sericilization, chloritization and K-feldspar alteration. Zoning of altered rocks adjacent to the Au-bearing quartz veins is obviously exhibited. Fine-grained sulphides and quartz veinlets of different ages and small-scale fissures are widely distributed in the central part of the altered zones. Major mineralization types in this gold deposit are Au-bearing quartz veinlets and altered rocks in the shear zones. Samples were collected from drilling cores according to the alteration zoning and mineralization type and all samples were analyzed for major and trace elements. Mass balance, volume change (fv=97.3–71.9%) and major element variation sequences are studied in terms of major elements. The changes of mobile components (SiO2, K2O, Fe2O3) and CaO) and immobile component (Al2O3) in the wall-rock alteration are discussed. The gold mineralization is associated with the enrichment of As, Ag, Hg and Pb and depletion of Cu and Zn. The study of compositional variation of altered rocks proves to be a very efficient method for defining the extent of wall-rock alteration, fluid activity and mineralization and enrichment.
文摘Osteoporosis and osteopenia are major health issues that mainly affect elderly people,women after menopause and immobilized patients.Our previous studies have proved that sclerostin antibody(Scl-Ab)can dramatically enhance bone formation and reduce bone resorption in a severe osteoporosis rat model with the combination of ovariectomy(OVX)and hindlimb immobilization(HLS).However,the mechanism in the cellular level is unclear.The objective of this study is to assess the effect of Scl-Ab on osteocytic morphology change in a combined OVX and HLS rat model via quantification of long-and short-axis and the ratio and osteocyte volume in midshaft cortical bone.Four-month-old virgin female SD rats were divided into 7 groups(n=11 per group):Sham+Veh,Sham+HLS+Veh,Sham+HLS+Scl-Ab,OVX+Veh,OVX+Scl-Ab,OVX+HLS+Veh,OVX+HLS+Scl-Ab.HLS was performed 2 weeks after sham or OVX surgery;and treatment was initiated at the time of HLS.Scl-Ab(25 mg/kg)or vehicle was subcutaneously injected twice per week for 5 weeks.Femurs were harvested at the end of study and embedded in PMMA and polished for SEM imaging.Cortical bone mid shaft osteocyte number per bone area was quantified under 1K magnification;the ratios between long axis and short axis of osteocytes were quantified under 2K magnification;osteocyte dendrite number and surface area were quantified under 5K magnification.Osteocyte dendrites width was quantified using 10K magnification.All the quantification was done by ImageJ.We have reported that multiple morphological and structural changes in osteocytes,including a decreased osteocyte density and reduced osteocyte dendrite number in HLS,OVX or the combination group and Scl-Ab’s ability to abolish these unfavorable alterations.We continued our SEM analysis on osteocytes and discovered that the oval shape of osteocyte under HLS,OVX or HLS+OVX has been distorted toward a spindle-like shape,with relatively longer long axis and shorter short axis,assuming osteocyte has a perfect spheroid shape.The ratio between long-and short-axis showed an increased trend in OVX and HLS condition,but Scl-Ab inhibited these increases(P<0.001,P<0.01,respectively).The volume decreased in HLS,OVX group,but Scl-Ab maintained osteocytes’volume in HLS condition(P<0.001).It indicates that cortical bone responds to HLS and/or OVX and Scl-Ab treatment via multiple cellular mechanisms,including density of osteocyte,dendrite number and osteocyte shape.The change of osteocyte shape may imply an altered cytoskeleton system within osteocyte and a subsequent disruption of mechanosensing ability for osteocyte,which lead to bone loss macroscopically.These data suggest Scl-Ab’s therapeutic potential could be related with its ability to maintain osteocyte’s morphologic and structural changes induced by OVX,HLS or both.
基金supported by the"973"Project (2005CB422105)the Program for Changjiang Scholars and Innovative Research Team at the University (PCSIRT IRT0658).
文摘Solid bitumens were found throughout the carbonate reservoirs in the Puguang gas field, the largest gas field so far found in marine carbonates in China, confirming that the Puguang gas field evolved from a paleo-oil reservoir. The fluid conduit system at the time of intensive oil accumulation in the field was reconstructed, and petroleum migration pathways were modeled using a 3-D model and traced by geochemical parameters. The forward modeling and inversion tracing coincided with each other and both indicated that oils accumulated in the Puguang-Dongyuezhai structure originated from a generative kitchen to the northwest of the Puguang gas field. The deposition of organic-rich Upper Permian source rocks dominated by sapropelic organic matter in the Northeast Sichuan Basin, the development of fluid conduit system that was vertically near-source rock and laterally near-generative kitchen, and the focusing of oils originated from a large area of the generative kitchen, were the three requirements for the formation of the giant paleo-oil reservoir from which the giant Puguang gas field evolved. The Puguang gas field had experienced a three-stage evolution. The post-accumulation processes, especially the organic-inorganic interaction in the hydrocarbon-water-rock system, had not only profoundly altered the composition and characteristics of the petroleum fluids, but also obviously changed the physicochemical conditions in the reservoir and resulted in complicated precipitation and solution of carbonate minerals.
基金This study was funded by Shanghai Science and Technology Committee(grant no.20ZR1448500,YDZX20213100001003,22YF1439100)the National Natural Science Foundation of China(grant no.82201678).
文摘Background Non-suicidal self-injury(NSSI)is a frequent and prominent phenomenon in major depressive disorder(MDD).Even though its prevalence and risk factors are relatively well understood,the potential mechanisms of NSSI in MDD remain elusive.Aims To review present evidence related to the potential mechanisms of NSSI in MDD.Methods According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines,articles for this systematic review were searched on Medline(through PubMed),Embase(through Elsevier),PsycINFO(through OVID)and Web of Science databases for English articles,as well as China National Knowledge Infrastructure(CNKI),SinoMed,Wanfang Data,and the Chongqing VIP Chinese Science and Technology Periodical(VIP)Databases for Chinese articles published from the date of inception to 2 August 2022.Two researchers(BW,HZ)independently screened studies based on inclusion and exclusion criteria and assessed their quality.Results A total of 25157 studies were searched.Only 25 of them were ultimately included,containing 3336 subjects(1535 patients with MDD and NSSI,1403 patients with MDD without NSSI and 398 HCs).Included studies were divided into 6 categories:psychosocial factors(11 studies),neuroimaging(8 studies),stress and hypothalamic-pituitary-adrenal(HPA)axis(2 studies),pain perception(1 study),electroencephalogram(EEG)(2 studies)and epigenetics(1 study).Conclusions This systematic review indicates that patients with MDD and NSSI might have specific psychosocial factors,aberrant brain functions and neurochemical metabolisms,HPA axis dysfunctions,abnormal pain perceptions and epigenetic alterations.
基金supported by the National Natural Science Foundation of China(11032008)Natural Science Foundation of Shanxi Province(2012011046-2)
文摘Laser in situ keratomileusis(LASIK)is a relatively new ophthalmic procedure in refractive surgery.It involves the use of a microkeratome to create a thin corneal flap followed by excimer laser ablation of the corneal stroma and repositioning of the flap.However,complications are bound to occur when a surgical procedure is performed with increasing frequency.In some cases,serious complications such as keratectasia occurred.Risk factors for corneal keratectasia include a thin cornea at baseline,thick corneal flap,excessive ablation,irregular corneal thickness,diverse ablation rates,preexisting keratoconus or form fruste keratoconus,and high intraocular pressure(IOP)~[1].It is evident from incisional refractive surgery that the cornea is not mechanically inert.The mechanical environment of the central corneal tissue is also altered un-
文摘Brass targets were irradiated with various laser pulses of Excimer laser ranging from 1200 to 3000 for constant fluence of 3.4 J/cm2 in oxygen atmosphere (100 Torr). The surface morphology and crystallographic analyses were performed by using Scanning Electron Microscope (SEM) and X-Ray Diffractometer (XRD). SEM analysis reveals the formation of laser-induced micro-sized cavities, bumps, cones and wave-like ridges with non-uniform shape and density distribution. These features are formed for all number of pulses;however with increasing number of pulses from 1200 to 2400, the density of cavities decreases whereas, the wave-like ridges become more pronounced and bump-formation is vanished. For maximum number of 3000 shots, the appearance of cones and wave-like ridges becomes diffusive, whereas the density and size of cavities increase again. XRD analysis demonstrates that no new phases are formed in irradiated brass. However, the change in peak intensity along with lower and higher angle shifting is observed which is attributed to generation of laser induced stresses. The Yield Stress (YS), Ultimate Tensile Strength (UTS) as well as Microhardness increase monotonically with increasing number of laser pulses.
文摘Based on analysing the wall rock alterations and related rocks which were used as a hint for mineral deposits and as a basis of mechanism research of fluid rock interaction, according to the results of petrographic analysis, the authors of this paper consider that the hydrothermally altered conglomerates have the following features. First, the conglomerates studied can be divided into two groups: Group A consists mainly of the gravels of granite and basalt; Group B is mainly composed of the gravels of basalt, limestone, mudstone and granite. Second, three distinct hydrothermal alterations or diagenesis were distinguished in Group A, that is, pre depositional hydrothermal alteration of the volcanic gravels (saussuritzation chloritization, epidotization chloritization, albitization and sericitization), mechanical diagenesis and post diagenetic hydrothermal alteration (epidote chlorite and prehnite calcite association). Third, the Group B is subjected mainly to pre depositional hydrothermal alteration; the alteration types are the same as of Type A. Last, the origin of the post diagenetic hydrothermal alteration of Group A is presumed to be related to the ascending of thermal water along the Naer Creek fault.
基金supported by the National Natural Science Foundation of China(81988101 to D.L.and to C.W.,82203156 to S.Z.)National Key Research and Development Program of China(2021YFC2501000 to D.L.,2023YFC3503200 to S.Z.)+1 种基金Medical and Health Technology Innovation Project of Chinese Academy of Medical Sciences(2021-I2M-1-013 to D.L.and to C.W.,2022-I2M-2-003 to D.L.)Beijing Outstanding Young Scientist Program(BJJWZYJH01201910023027 to C.W.).
文摘Tumorigenesis is a multistep process,with oncogenic mutations in a normal cell conferring clonal advantage as the initial event.However,despite pervasive somatic mutations and clonal expansion in normal tissues,their transformation into cancer remains a rare event,indicating the presence of additional driver events for progression to an irreversible,highly heterogeneous,and invasive lesion.Recently,researchers are emphasizing the mechanisms of environmental tumor risk factors and epigenetic alterations that are profoundly influencing early clonal expansion and malignant evolution,independently of inducing mutations.Additionally,clonal evolution in tumorigenesis reflects a multifaceted interplay between cell-intrinsic identities and various cell-extrinsic factors that exert selective pressures to either restrain uncontrolled proliferation or allow specific clones to progress into tumors.However,the mechanisms by which driver events induce both intrinsic cellular competency and remodel environmental stress to facilitate malignant transformation are not fully understood.In this review,we summarize the genetic,epigenetic,and external driver events,and their effects on the co-evolution of the transformed cells and their ecosystem during tumor initiation and early malignant evolution.A deeper understanding of the earliest molecular events holds promise for translational applications,predicting individuals at high-risk of tumor and developing strategies to intercept malignant transformation.
基金financially supported by the project of the China Geological Survey(DD20230292,DD20242591)。
文摘The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of Au.This paper presents a new understanding for Dongping ore system,based on the previous studies.The mineralization originally occurred at 400-380 Ma,simultaneous with emplacement of the Shuiquangou alkaline complex,and was overprinted by the hydrothermal activity in the Yanshanian.Isotope compositions of ores indicate metals of the deposit are mainly provided by the Shuiquangou complex.Ore-forming fluids are characterized by increasing oxygen fugacity and decreasing sulfur fugacity,while tellurium fugacity increased in the Stage II-2 and decreased in Stage II-3.These systematic changes are closely related to the processes of mineral precipitation and fluid evolution.Sulfide precipitation from Stage Ⅰ to Stage Ⅱ was triggered by fluid boiling,which leads to the precipitation of Pb-Bi-Te,due to decrement of sulfur fugacity.Condensation of gas phase containing high concentration of H_2Te leads to precipitation of Te-Au-Ag minerals and native tellurium.Based on these hypotheses,this paper present a polyphase metallogenic model as follow.During the Devonian,fluids were released from alkaline magmas,which carried ore-forming materials form the surrounding rocks and precipitate the early ores.During the Jurassic-Cretaceous,fluorine-rich fluids exsolved from highly factionated Shangshuiquan granite,which extracted and concentrated Au from the Shuiquangou complex and the Sanggan Group metamorphic rocks,and finally formed the Dongping gold deposit.
文摘Over the last 30 years,a new actor in the area of ecology and evolution has emerged:niche construction theory(NCT).The fundamental premise of NCT is that organisms may actively influence evolutionary processes by modifying their circumstances[1].According to Trappes et al.,[2]the concept of niche construction should only be applied to species that alter their environment,which they believe to be its intuitive scope.They add two more terms to describe the ways that organisms engage with their surroundings and so influence their niches:when organisms choose their environment,this is known as niche choice,and when they adapt their phenotype to fit their environment,this is known as niche conformance.These three concepts are often referred to as niche-altering mechanisms,or NC3 mechanisms:niche conformance,niche construction,and niche choice.This is in line with definitions of mechanisms developed in scientific philosophy[2].