Studies have shown that differentiated embryo-chondrocyte expressed gene 1(DEC1)promotes osteoblast osteogenesis.To investigate the role of DEC1 in postmenopausal osteoporosis,we used the two genotypes of mice(Dec1+/+...Studies have shown that differentiated embryo-chondrocyte expressed gene 1(DEC1)promotes osteoblast osteogenesis.To investigate the role of DEC1 in postmenopausal osteoporosis,we used the two genotypes of mice(Dec1+/+and Dec1-/-)to establish an ovariectomy model and found that the bone loss was significantly lower in Dec1-/-ovariectomy mice than in Dec1+/+ovariectomy mice.The expression levels of RUNX2 and OSX were significantly increased in Dec1-/-ovariectomy mice,compared with Dec1+/+ovariectomy mice;however,the expression levels of NFATc1,c-Fos,CTSK,and RANKL/OPG ratio were significantly decreased in Dec1-/-ovariectomy mice,compared with those in Dec1+/+ovariectomy mice.Likewise,DEC1 deficiency also suppressed the expression levels of IL-6 and IL-1β.Further results showed that the mRNA expression levels of Runx2,Osx,and Alp were significantly increased in bone marrow mesenchymal stem cells of Dec1-/-ovariectomy mice,compared with those of Dec1+/+ovariectomy mice.Moreover,the mRNA levels of Il1b,Il6,Tnfa,and Ifng were significantly increased in bone marrow-derived macrophages(BMMs)of Dec1+/+ovariectomy mice,compared with those of Dec1+/+sham mice,but not in Dec1-/-ovariectomy BMMs,when compared with those in Dec1-/-sham BMMs.Additionally,the expression levels of p-IκBαand p-P65 were significantly increased in Dec1+/+ovariectomy BMMs,compared with those in Dec1+/+sham BMMs,but did not increase in Dec1-/-ovariectomy BMMs,compared with those in Dec1-/-sham BMMs.Taken together,DEC1 deficiency inhibited the NF-κB pathway induced by ovariectomy,thereby decreasing cytokines and subsequently inhibiting the decrease of osteo-genesis and the increase of osteoclastogenesis caused by ovariectomy.The findings may provide a novel under-standing of postmenopausal osteoporosis development,and offer potential avenues for the disease intervention.展开更多
Catastrophic geological disasters frequently occur on slopes with obliquely inclined bedding structures(also referred to as obliquely inclined bedding slopes),where the apparent dip sliding is not readily visible.This...Catastrophic geological disasters frequently occur on slopes with obliquely inclined bedding structures(also referred to as obliquely inclined bedding slopes),where the apparent dip sliding is not readily visible.This phenomenon has become a focal point in landslide research.Yet,there is a lack of studies on the failure modes and mechanisms of hidden,steep obliquely inclined bedding slopes.This study investigated the Shanyang landslide in Shaanxi Province,China.Using field investigations,laboratory tests of geotechnical parameters,and the 3DEC software,this study developed a numerical model of the landslide to analyze the failure process of such slopes.The findings indicate that the Shanyang landslide primarily crept along a weak interlayer under the action of gravity.The landslide,initially following a dip angle with the support of a stable inclined rock mass,shifted direction under the influence of argillization in the weak interlayer,moving towards the apparent dip angle.The slide resistance effect of the karstic dissolution zone was increasingly significant during this process,with lateral friction being the primary resistance force.A reduction in the lateral friction due to karstic dissolution made the apparent dip sliding characteristics of the Shanyang landslide more pronounced.Notably,deformations such as bending and uplift at the slope’s foot suggest that the main slide resistance shifts from lateral friction within the karstic dissolution zone to the slope foot’s resistance force,leading to the eventual buckling failure of the landslide.This study unveils a novel failure mode of apparent dip creep-buckling in the Shanyang landslide,highlighting the critical role of lateral friction from the karstic dissolution zone in its failure mechanism.These insights offer a valuable reference for mitigating risks and preventing disasters related to obliquely inclined bedding landslides.展开更多
通过三维离散元分析软件3DEC(3 Dimensional Distinct Element Code),针对卸压孔在不同孔径下的围岩变形情况,较为详细地分析了钻孔卸压在深部巷道中的效果。模拟结果表明,对巷道两帮钻孔卸压以后,应力集中区域由两帮转移到了围岩深部,...通过三维离散元分析软件3DEC(3 Dimensional Distinct Element Code),针对卸压孔在不同孔径下的围岩变形情况,较为详细地分析了钻孔卸压在深部巷道中的效果。模拟结果表明,对巷道两帮钻孔卸压以后,应力集中区域由两帮转移到了围岩深部,且集中在了卸压孔的末端,对深部巷道起到了很好的保护作用,为深部高应力巷道卸压支护提供了依据。展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.82073934 and 81872937 to J.Y.)the Special Foundation for Clinical Science and Technology of Jiangsu Province(Grant No.JX10114120).
文摘Studies have shown that differentiated embryo-chondrocyte expressed gene 1(DEC1)promotes osteoblast osteogenesis.To investigate the role of DEC1 in postmenopausal osteoporosis,we used the two genotypes of mice(Dec1+/+and Dec1-/-)to establish an ovariectomy model and found that the bone loss was significantly lower in Dec1-/-ovariectomy mice than in Dec1+/+ovariectomy mice.The expression levels of RUNX2 and OSX were significantly increased in Dec1-/-ovariectomy mice,compared with Dec1+/+ovariectomy mice;however,the expression levels of NFATc1,c-Fos,CTSK,and RANKL/OPG ratio were significantly decreased in Dec1-/-ovariectomy mice,compared with those in Dec1+/+ovariectomy mice.Likewise,DEC1 deficiency also suppressed the expression levels of IL-6 and IL-1β.Further results showed that the mRNA expression levels of Runx2,Osx,and Alp were significantly increased in bone marrow mesenchymal stem cells of Dec1-/-ovariectomy mice,compared with those of Dec1+/+ovariectomy mice.Moreover,the mRNA levels of Il1b,Il6,Tnfa,and Ifng were significantly increased in bone marrow-derived macrophages(BMMs)of Dec1+/+ovariectomy mice,compared with those of Dec1+/+sham mice,but not in Dec1-/-ovariectomy BMMs,when compared with those in Dec1-/-sham BMMs.Additionally,the expression levels of p-IκBαand p-P65 were significantly increased in Dec1+/+ovariectomy BMMs,compared with those in Dec1+/+sham BMMs,but did not increase in Dec1-/-ovariectomy BMMs,compared with those in Dec1-/-sham BMMs.Taken together,DEC1 deficiency inhibited the NF-κB pathway induced by ovariectomy,thereby decreasing cytokines and subsequently inhibiting the decrease of osteo-genesis and the increase of osteoclastogenesis caused by ovariectomy.The findings may provide a novel under-standing of postmenopausal osteoporosis development,and offer potential avenues for the disease intervention.
基金jointly supported by the projects of the China Geological Survey(DD20230092,DD20201119)。
文摘Catastrophic geological disasters frequently occur on slopes with obliquely inclined bedding structures(also referred to as obliquely inclined bedding slopes),where the apparent dip sliding is not readily visible.This phenomenon has become a focal point in landslide research.Yet,there is a lack of studies on the failure modes and mechanisms of hidden,steep obliquely inclined bedding slopes.This study investigated the Shanyang landslide in Shaanxi Province,China.Using field investigations,laboratory tests of geotechnical parameters,and the 3DEC software,this study developed a numerical model of the landslide to analyze the failure process of such slopes.The findings indicate that the Shanyang landslide primarily crept along a weak interlayer under the action of gravity.The landslide,initially following a dip angle with the support of a stable inclined rock mass,shifted direction under the influence of argillization in the weak interlayer,moving towards the apparent dip angle.The slide resistance effect of the karstic dissolution zone was increasingly significant during this process,with lateral friction being the primary resistance force.A reduction in the lateral friction due to karstic dissolution made the apparent dip sliding characteristics of the Shanyang landslide more pronounced.Notably,deformations such as bending and uplift at the slope’s foot suggest that the main slide resistance shifts from lateral friction within the karstic dissolution zone to the slope foot’s resistance force,leading to the eventual buckling failure of the landslide.This study unveils a novel failure mode of apparent dip creep-buckling in the Shanyang landslide,highlighting the critical role of lateral friction from the karstic dissolution zone in its failure mechanism.These insights offer a valuable reference for mitigating risks and preventing disasters related to obliquely inclined bedding landslides.
文摘通过三维离散元分析软件3DEC(3 Dimensional Distinct Element Code),针对卸压孔在不同孔径下的围岩变形情况,较为详细地分析了钻孔卸压在深部巷道中的效果。模拟结果表明,对巷道两帮钻孔卸压以后,应力集中区域由两帮转移到了围岩深部,且集中在了卸压孔的末端,对深部巷道起到了很好的保护作用,为深部高应力巷道卸压支护提供了依据。
