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| 1 | China's lakes at present:Number,area and spatial distribution显示文摘Based on 11004 satellite images from CBERS CCD and Landsat TM/ETM,changes in the spatial characteristics of all lakes in China were determined following pre-established interpretation rules.This dataset was supported by 6843 digital raster images(1:100000 and 1:50000),a countrywide digital vector dataset(1:250000),and historical literature.Comparative data were corrected for seasonal variations using precipitation data.There are presently 2693 natural lakes in China with an area greater than 1.0 km2,excluding reservoirs.These lakes are distributed in 28 provinces,autonomous regions and municipalities and have a total area of 81414.6 km2,accounting for-0.9% of China's total land area.In the past 30 years,the number of newly formed and newly discovered lakes with an area greater than 1.0 km2 is 60 and 131,respectively.Conversely,243 lakes have disappeared in this time period. | MA RongHua YANG GuiShan DUAN HongTao JIANG JiaHu WANG SuMin FENG XueZhi LI AiNong KONG FanXiang XUE Bin WU JingLu LI ShiJie | 2011 | Science China Earth Sciences2011，54，2： | 79 |
| 2 | Southwest monsoon changes indicated by oxygen isotope of ostracode shells from sediments in Qinghai Lake since the late Glacial显示文摘The δ 18O records of ostracode shells in sediments of core QH-2000 from Qinghai Lake can be used as a better proxy to reflect monsoon changes. Low monsoon precipitation between 17.5 and 11 cal. ka BP is indicated by positive δ 18O values averaging 2.37‰. A fast shift in δ 18O from positive at 11 cal. ka BP to negative at 10 cal. ka BP indicates sharp increase of monsoon precipitation. An interval of generally high monsoon precipitation is observed between 10 and 6 cal. ka BP with δ 18O values averaging -2.15‰. Decrease of monsoon precipitation between 6 and 2.5 cal. ka BP is indicated by positive δ 18O values. δ 18O keeps positive values averaging 3.0‰ between 2.5 and 0 cal. ka BP suggesting low high monsoon precipitation. The climatic changes indicated by δ 18O records of ostracode shells in sedi- ments of core QH-2000 from Qinghai Lake and our broader regional comparison show that the climate in Qinghai Lake since the late Glacial is probably controlled by southwest monsoon other than southeast monsoon. | LIU XingQi SHEN Ji WANG SuMin WANG YongBo LIU WeiGuo | 2007 | Chinese Science Bulletin2007，52，4： | 39 |
| 3 | A 16000-year pollen record of Qinghai Lake and its paleoclimate and paleoenvironment显示文摘The paleoclimate and paleoenvironment of Qinghai Lake indicated by a 16000-year pollen record are as follows. It was very cold and dry before 15200 years. During the Late Glacial, the climate varied from colder and semiarid to cool and semi-humid and fluctuated frequently but with little amplitude. Three cold events in the periods of 13400-13000, 11600-12000, and 11000-10400 aBP respectively correspond to the Oldest Dryas, Older Dryas and Younger Dryas events, whereas the two warm periods between them, 12000-13000 and 11600-11000 aBP, respectively correspond to Boiling and Allerod periods. The temperature increased abruptly after the Younger Dryas event, and then the climate gradually turned to be warm and wet from warm and semiarid. In the Holocene, the largest amplitude of cold event that occurred at ca. 8200 aBP is quite prominent. The Holocene climatic optimum culminated at 6700 aBP. After 2100 aBP, the climate tended to be cold and dry, keeping on up to now. Palaeoclimatic evolution and events of | LIU Xingqi SHEN Ji WANG Sumin YANG Xiangdong TONG Guobang ZHANG Enlou | 2002 | Chinese Science Bulletin2002，47，22： | 33 |
| 4 | New progress of lake sediments and environmental changes research in China显示文摘Environmental change recorded by lake sediments is one of the important branches of the past global changes study. The new progress of lake sediments and environmental changes in China since the late 1980s has been comprehensively discussed. The highlights emphasized are Asian paleomonsoon migration reflected by lake level fluctuation, uplift of the Qinghai-Xizang Plateau recorded by lacustrine sediments, saltlake sediments and | WANG Sumin and ZHANG ZhenkeLaboratory of Lake Sediment and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences , Nanjing 210008, China Department of Geography and Oceanology, Nanjing University , Nanjing 210093 , China | 1999 | Chinese Science Bulletin1999，44，19： | 22 |
| 5 | Simulated and reconstructed winter temperature in the eastern China during the last millennium显示文摘The reconstructed temperature anomalies in the eastern China were compared with the output from a 1000-year model simulation in an attempt to evaluate the model’s regional simulation skills and to understand the causes of climate change in China over the last millennium. The reconstructed data are the winter half-year temperature anomalies in the central region of eastern China (25°-40°N, east of 105°E) for the last 1000 years with a 30-year resolu- tion. The model used is the global atmosphere-ocean coupled climate model, ECHO-G, which was driven by time-varying external forcings including solar radiation, volcanic erup- tions, and greenhouse gas concentrations (CO2 and CH4) for the same period. The correlation coefficient between the simulated and reconstructed time series is 0.37, which is sta- tistically significant at a confidence level of 97.5%. The Me- dieval Warm Period (MWP) during 1000-1300 A.D., the Little Ice Age (LIA) during 1300-1850 A.D. and the modern warming period after 1900 A.D. are all recognizable from both the simulated and reconstructed temperatures. The anomalies associated with the LIA and the modern warming simulated by the model are in good consistency with the re- constructed counterpart. In particular during the Maunder sun-spot minimum (1670-1710 A.D.), both the simulated and reconstructed temperature anomalies reach their min- ima without any phase difference. But in the earlier MWP, significant discrepancies exist between the simulation and the reconstruction, which might reflect the degrading quality of the reconstruction data. The range of the simulated anoma- lies (1.62 K) is comparable with that of reconstructed (2.0 K). Diagnosis of the model results indicates that, during the last millennium, variations in solar radiation and volcanic activ- ity are the main controlling factors on regional temperature change, while in the recent 100 years, the change of the con- centration of greenhouse gases plays most important role in explaining the rapid temperature rising. | LIU Jian H. Storch CHEN Xing E. Zorita ZHENG Jingyun WANG Sumin | 2005 | Chinese Science Bulletin2005，50，24： | 21 |
| 6 | Preliminary study on LGM climate simulation and the diagnosis for East Asia显示文摘LGM climate study is a hot topic in international fields on global changes. Climate simulation in this study applies both common designs of 21 kaBP boundary conditions from the Paleoclimate Modeling Intercomparison Project (PMIP), including insolation, glaciation, sea surface temperature and atmospheric CO2 concentration, and land surface conditions from Eurasia continent by compilation of geological evidence. The simulation outputs are in agreement with climate spatial patterns reconstructed by observation records. Sensitive experiment on land surface conditions shows that changes in vegetation would make significant impacts on temperature and precipitation. Particularly in the Tibetan Plateau, this change would increase in differences of winter and summer temperature, precipitation and P-E. | YU Ge CHEN Xing LIU Jian WANG Sumin | 2001 | Chinese Science Bulletin2001，46，5： | 16 |
| 7 | PERFORMANCE ANALYSIS OF POLLING SYSTEMS WITH LIMITED SERVICE显示文摘This paper analyzes a queue mode] of the polling system with limited service (K=1) in discrete time. By the imbedded Markov chain theory and the probability generating function method, the mean values of queue length and message waiting time are explicitly obtained. Also, we give the simulation results. The results obtained by H. Tagai (1985) are revised. | Zhao Dongfeng Li Bihai Zheng Sumin(Department of Information and Electronic Science, Yunnan University, Kunming 650091) | 1998 | Journal of Electronics(China)1998，15，1： | 12 |
| 8 | Connexin 43 hemichannels protect bone loss during estrogen deficiency显示文摘Estrogen deficiency in postmenopausal women is a major cause of bone loss,resulting in osteopenia,osteoporosis,and a high risk for bone fracture.Connexin 43 (Cx43) hemichannels (HCs) in osteocytes play an important role in osteocyte viability,bone formation,and remodeling.We showed here that estrogen deficiency reduced Cx43 expression and HC function.To determine if functional HCs protect osteocytes and bone loss during estrogen deficiency,we adopted an ovariectomy model in wild-type (WT) and two transgenic Cx43 mice:R76W (dominant-negative mutant inhibiting only gap junction channels) and Cx43 Δ130–136 (dominant-negative mutant compromising both gap junction channels and HCs).The bone mineral density (BMD),bone structure,and histomorphometric changes of cortical and trabecular bones after ovariectomy were investigated.Our results showed that the Δ130–136 transgenic cohort had greatly decreased vertebral trabecular bone mass compared to WT and R76W mice,associated with a significant increase in the number of apoptotic osteocyte and empty lacunae.Moreover,osteoclast surfaces in trabecular and cortical bones were increased after ovariectomy in the R76W and WT mice,respectively,but not in Δ130–136 mice.These data demonstrate that impairment of Cx43 HCs in osteocytes accelerates vertebral trabecular bone loss and increase in osteocyte apoptosis,and further suggest that Cx43 HCs in osteocytes protect trabecular bone against catabolic effects due to estrogen deficiency. | Liang Ma Rui Hua Yi Tian Hongyun Cheng Roberto Jose Fajardo Joseph J. Pearson Teja Guda Daniel Brian Shropshire Sumin Gu Jean X. Jiang | 2019 | Bone Research2019，7，2： | 11 |
| 9 | Finite element simulation and experimental test of the wear behavior for self-lubricating spherical plain bearings显示文摘In this study, based on the classical Archard adhesion wear theory, a three-dimensional finite element model was established, with the aim of simulating the failure process of self-lubricating spherical plain bearings in the swinging wear condition. The results show that the self-lubricating spherical plain bearings go through two different stages during the wear process, namely, initial wear stage and stable wear stage. Because the large contact points wear out during the initial wear stage, the maximum contact pressure decreases as the test period increases. The relatively larger wear depth region shows elliptical distribution, and the maximum distribution appears in the central contact area. The wear depth reaches 0.974 mm after swinging 25,000 times. PTFE fibers, which possess a good friction performance but poor abrasion resistance, abundantly exist on the friction surfaces of the fabric liner. Consequently, the friction torque during the initial wear stage is slightly smaller than the friction torque during the stable wear stage; however, the wear rate during the initial wear stage is high. The reliability and effectiveness of the finite element model are verified by experiment. The developed finite element model can be used for the analysis of the wear mechanisms of bearings and the prediction of the service life of bearings. | Yahong XUE Jigang CHEN Sumin GUO Qingliang MENG Junting LUO | 2018 | Friction2018，6，3： | 11 |
| 10 | Variation characteristics of heavy metals and nutrients in the core sediments of Taihu Lake and their pollution history显示文摘The sedimentary environment change, trophic evolution and heavy metals pollution history of the northern Taihu Lake in the last 100 years are studied according to the sedimentary geochemical proxies of the core sediments, such as grain size, nutrients, heavy metals, diatom, etc. The nutrients in the sediments depended mainly on the lake internal circulation and the heavy metals were from natural geogenic sources before the 1920s, which were not influenced by human activities generally, and grain size was one of the key factors influencing heavy metals content in the sediments.The alternation of manner and strength of human activities in Taihu Lake catchment before and after the 1920s made the lake sediments coarser, and hence heavy metals and TP content decreased contrasted with that before the 1920s. TP content in sediments and water increased from the 1950s to late 1970s due to anthropogenic pollutants discharge, and the lake belonging to mesotrophic state.TN and TOC content and C/N ratio increased due to the increasing external pollutants into Taihu Lake by human activities, TP content also increased obviously in water and sediments, and the diatom association was dominated by eutrophic species since the late 1970s, indicating the eutrophication state of Taihu Lake in this period. Meanwhile the increasing in heavy metals content, such as Cu, Mn,Ni, Pb and Zn, and their proportion of valid fractions in the sediments indicates that they all result from human pollutants since the late 1970s. The heavy metals in the surface sediments have certain potential biological toxicity due to the higher SEM/AVS ratio. | LIU Enfeng SHEN Ji LIU Xingqi ZHU Yuxin WANG Sumin | 2006 | Science China Earth Sciences2006，49，z1： | 11 |
| 11 | Palynological evidence for vegetational and climatic changes from the HQ deep drilling core in Yunnan Province, China显示文摘The high-resolution pollen study of a 737.72-m-long lake sediment core in the Heqing Basin of Yunnan Province shows that the vegetation and climate of mountains around the Heqing Basin went through six obvious changes since 2.780 Ma B.P. Namely, Pinus forest occupied most mountains around the studied area and the structure of vertical vegetational belt was simple between 2.780 and 2.729 Ma B.P., reflecting a relatively warm and dry climate. During 2.729―2.608 Ma B.P., the areas of cold-temperate conifer forest (CTCF) and Tsuga forest increased and the structure of vertical vegetational belt became clear. According to percentages of tropical and subtropical elements growing in low-altitude regions rifely increased, we speculate that the increase of CTCF and Tsuga forest areas mainly resulted from strong uplift of mountains which provided upward expanding space and growing condition for these plants. Thus, the climate of the low-altitude regions around the basin was relatively warm and humid. Between 2.608 and 1.553 Ma B.P., Pinus forest occupied most mountains around the studied area and forest line of CTCF rose, which reflects a moderately warm-dry climate on the whole. During 1.553―0.876 Ma B.P., the structure of vertical vegetational belt in mountains around the studied area became complicated and the amplitude of vegetational belts shifting up and down enlarged, which implies that the amplitude of climatic change increased, the climatic associational feature was more complex and the climate was moderately cold at a majority of the stage. During 0.876―0.252 Ma B.P., there were all vertical vegetational belts existing at present in mountains around the studied area. The elements of each belt were more abundant and complex than earlier. At different periods in the stage vertical vegetational belts occurred as expanding or shrinking, and alternated each other. The amplitude of vegetational belts shifting up and down was the maximum in the whole section. This change suggests that the amplitude of climatic change was evidently larger than earlier, but the frequency reduced and the climatic associational feature was more complex. From 0.252 Ma B.P. to the present, the most time was characteristic of the expanding of Pinus forest and semi-humid evergreen broad-leaved forest (SEBF) in mountains around the studied area, while expanding time of other vegetational belts was very short, which reflects a smaller amplitude of cold and warm fluctuation. On the basis of the six obvious cycles of vegetational and climatic changes, there were still many times of secondary vegetational successions and climatic oscillations. Based on the above analysis, the forcing mechanism of vegeta-tional succession and climatic change in the Heqing Basin is further discussed. It is primarily consid-ered that main influential factors were exterior factors such as orbital parameters, etc., but the uplift of the Qinghai-Tibet Plateau played a very important function for environmental changes in the Heqing Basin at two times obvious increase of vertical vegetational belts and three climatic transitions. | XIAO XiaYun SHEN Ji WANG SuMin XIAO HaiFeng TONG GuoBang | 2007 | Science China Earth Sciences2007，50，8： | 10 |
| 12 | Characteristics of an early Holocene climate and environment from lake sediments in Ebinur region, NW China显示文摘The characteristics of climatic environment in the early Holocene epoch were studied through analyzing environmental proxies from the sediments in the Ebinur Lake--a closed one in the arid region. The pollen assemblage and other geochemical indices showed that, the temperature was somewhat low in the period (8.0-11.5 cal kaBP) as a whole, but in the early period (11.5-10.6 cal kaBP) the temperature was higher, in company with more precipitation. In the conversion period from the early Holocene epoch to the middle Holocene epoch (8.9-8.0 cal kaBP) the climate fluctuated remarkably. Particularly the three layers of peat sediment revealed the strong instability of climate in the early Holocene epoch in the Ebinur region. All information on the development of peat and the experimental data of pollen and stable isotopes implied that, the climatic condition at 8.2, 8.6 and 10.5 cal kaBP was characterized by noticeable cold and humidness, and could be regarded as three cold and humid events in the early Holocene epoch. | WU Jinglu SHEN Ji WANG Sumin JIN Zhangdong YANG Xiangdong | 2005 | Science China Earth Sciences2005，48，2： | 10 |
| 13 | A subfossil chironomid-total phosphorus inference model for lakes in the middle and lower reaches of the Yangtze River显示文摘The results of an investigation into the relationship between surface sediment subfossil chi- ronomid distribution and water quality are presented. Data from 30 lakes in the middle and lower reaches of the Yangtze River indicate that the nutrient gradi- ent was the major factor affecting the distribution of chironomids across these sites. Canonical corre- spondence analysis (CCA) revealed that of 12 sum- mer water environmental variables, total Phosphorus was most important, accounting for 20.1% of the variance in the chironomid data. This was significant enough to allow the development of quantitative in- ference models. A TP inference model was devel- oped using weighted averaging (WA), partial least squares (PLS) and weighted averaging partial least squares (WA-PLS). An optimal two-component WA-PLS model provided a high jack-knifed coeffi- cient of prediction for conductivity r 2jack = 0.76, with a low root mean squared error of prediction (RMSEPjack = 0.13). Using this model it is possible to produce long-term quantitative records of past water quality for lacustrine sites across the middle and lower reaches of the Yangtze River, which has important implications for future lake management and eco- logical restoration. | ZHANG Enlou Alan Bedford Richard Jones SHEN Ji WANG Sumin TANG Hongqu | 2006 | Chinese Science Bulletin2006，51，17： | 10 |
| 14 | Intermetallic phase formation and evolution during homogenization and solution in Al-Zn-Mg-Cu alloys显示文摘The effects of major alloy element contents of Zn,Mg,Cu in Al-Zn-Mg-Cu alloys on the formation and evolution of intermetallic phases during casting,homogenization and solution treatment have been investigated through using X-ray diffraction,scanning electron microscopy and differential scanning calorimetry.Experimental results showed that a relatively higher Zn content with lower Mg and Cu contents was beneficial to the formation of MgZn2phase instead of the Al2CuMg phase,which resulted in the unicity of the intermetallics in the Al matrix,and that the MgZn2phase was easier for diffusion and dissolution during homogenization and solution than the Al2CuMg phase.Additionally,the results of the first-principles calculations gave support for explaining the experimental phenomena.A larger absolute value of formation enthalpy and a smaller value of binding energy of the MgZn2phase,as compared with the Al2CuMg phase,give it priority to precipitate during casting and make it easier to re-dissolve during homogenization and solution treatment.What’s more,higher elastic constants with severe anisotropy of Young’s modulus make undissolved blocks of Al2CuMg phase act as crack initiation,which degrade the performance of the materials. | LI ChunMei CHEN ZhiQian ZENG SuMin CHENG NanPu CHEN TianXiao | 2013 | Science China(Technological Sciences)2013，56，11： | 10 |
| 15 | Lake records and LGM climate in China显示文摘Chinese lake status database has provided systematic geological records of much higher lake level and fresher water than today at the LGM from western China. This wet condition was significant contrast with very dry conditions in eastern China. Together with lake studies from Eurasian continents, there was a wet-condition belt from the Mediterranean and the Middle East, Central Asia to western China. Palaeoclimate simulations confirmed that the wet conditions in western China were produced by decrease of the evaporation and increase of precipitation by positive anomaly of annual P-E of 70-95 mm/a between the LGM and today. The westerlies enhanced in the strength and shifted southwards-eastwards in the position, and the low thermal conditions in the Eurasian continent creating temperature 4-16℃ lower than today and relatively low evaporation, were the major two important climate conditions to yield cold-wet climates in western China. | Ge Yu Bin Xue Sumin Wang Jian Liu | 2000 | Chinese Science Bulletin2000，45，13： | 9 |
| 16 | Spatio-temporal variations of the bacterioplankton community composition in Chaohu Lake, China显示文摘Despite considerable attention paid to Chaohu Lake in China, the dynamics of bacterioplankton community composition (BCC) on spatial and seasonal scales are poorly understood.In this study, water samples were collected from autumn 2006 to summer 2007 at five positions in Chaohu Lake with difierent trophic status.BCC of these samples was determined by both the PCR amplification of the 16S rDNA gene and the denaturing gradient gel electrophoresis (DGGE).The abundance and diversity of bacterioplankton communities at difierent sampling positions showed similar seasonal patterns.The BCCs in the samples varied substantially, and the pattern of changes indicated that the seasonal difierence might have a significant impact on the BCC's structure in the lake.Canonical correspondence anal-ysis (CCA) on the DGGE patterns and physicochemical parameters indicated that the temperature and the levels of 5-d biochemical O2 demand (BOD5), NH3-N, CODMn, total nitrogen, total phosphorous, and dissolved oxygen significantly infiuenced the BCC, and four of the seven variables were related to the level of eutrophication.Our results indicate that eutrophic status and season are the most infiu-ential factors in determining BCC in Chaohu Lake. | Chaoling Wei Sumin Bao Xinyan Zhu Xiangming Huang | 2008 | Progress in Natural Science:Materials International2008，18，9： | 9 |
| 17 | Historical trophic evolutions and their ecological responses from shallow lakes in the middle and lower reaches of the Yangtze River: Case studies on Longgan Lake and Taibai Lake显示文摘The evolutions of diatom floras and the total phosphorous (TP) concentrations in the historical period were reconstructed for two lakes, Longgan and Taibai in the middle Yangtze River,based on high resolutional fossil diatom study from two sediment cores and an established regional diatom-TP transfer function. The TP concentration in Longgan Lake changed slightly in the range of 36-62 μg/L and kept its middle trophic level in the past 200 years. The changes of diatom assemblages reflect a macrophyte-dominated history of the lake. During the nineteenth century, the lake TP concentration increased comparatively, corresponding to the increase in abundance of benthic diatoms. The progressive increase of epiphytic diatoms since the onset of the twentieth century indicates the development of aquatic plants, coinciding with the twice drops of water TP level. The TP concentration in Taibai Lake kept a stable status about 50 μg/L before 1953 AD, while diatoms dominated by facultative planktonic Aulacoseira granulata shifted quickly to epiphytic diatom species, indicating a rapid expansion of aquatic vegetation. During 1953-1970 AD, the coverage of aquatic plants decreased greatly inferred by the low abundance of epiphytic diatoms as well as declined planktonic types, and the reconstructed TP concentration shows an obvious rising trend firstly, suggesting the beginning of the lake eutrophication. The lake was in the eutrophic condition after 1970, coinciding with the successive increase of planktonic diatoms. The comparison of the two lakes suggests the internal adjustment and purification function of aquatic plants for nutrients in water. The discrepancy of TP trends in the two lakes after 1960 reflects two different patterns of lake environmental response to human disturbance. Sediments in Taibai Lake clearly recorded the process of lake ecological transformation from the macrophyte-dominated stage to the algae-dominated stage. The limits of TP concentration (68-118 μg/L) in the transitional state can be considered as the critical value between the two stable ecosystems. Further work will be necessary to provide more evidence from the sediments in more eutrophic lakes for the primary inference. The reconstructive TP level and the inference of aquatic plants from fossil diatoms in different lakes, as well as their comparison provide a scientific basis for ecological restoration of eutrophic lakes in research regions. | YANG Xiangdong SHEN Ji DONG Xuhui LIU Enfeng WANG Sumin | 2006 | Science China Earth Sciences2006，49，z1： | 8 |
| 18 | The plant diversity and its relationship with paleoenvironment since 2.78 Ma revealed by pollen records in the Heqing deep drilling core显示文摘Multifold palynological diversity indices calculated by pollen data of the Heqing deep drilling core are synthetically analyzed, the results show that the plant diversity rapidly increased and its fluctuant amplitude and frequency evidently largened during the stages of 2.729―2.608 Ma, 1.176―0.342 Ma and since 0.118 Ma respectively, while during the other periods the plant diversity was relatively low with a gentle fluctuation. To discuss further the relation between ancient plant diversity and paleoenvironment, it is considered that the plant diversity in the Heqing region lies on increase or decrease of vertical vegetational belts in mountains around the studied area and richness of components of these vegetational belts, and is controlled by amplitude of tectonic uplift of mountains and climatic changes. The high plant diversity during 2.729―2.608 Ma responded to the strong uplift of mountains at the stage, while the plant diversity greatly increased and its fluctuant amplitude and frequency markedly largened at about 1.176 Ma was obviously response to the Middle Pleistocene Transition. The plant diversity and its fluctuant amplitude and frequency increased further at about 0.991 Ma may be superposably affected by both the Middle Pleistocene Transition and the tectonic uplift. The plant diversity increased since 0.118 Ma may indicate that the southwest monsoon strengthened and humid climate more fitted many kinds of plants to grow. | XIAO XiaYun SHEN Ji WANG SuMin XIAO HaiFeng TONG GuoBang | 2008 | Chinese Science Bulletin2008，53，23： | 8 |
| 19 | Mechanotransduction via the coordinated actions of integrins,PI3K signaling and Connexin hemichannels显示文摘Mechanical loading opens connexin 43(Cx43)hemichannels(HCs),leading to the release of bone anabolic molecules,such as prostaglandins,from mechanosensitive osteocytes,which is essential for bone formation and remodeling.However,the mechanotransduction mechanism that activates HCs remains elusive.Here,we report a unique pathway by which mechanical signals are effectively transferred between integrin molecules located in different regions of the cell,resulting in HC activation.Both integrinα5 andαV were activated upon mechanical stimulation via either fluid dropping or flow shear stress(FSS).Inhibition of integrinαV activation or ablation of integrinα5 prevented HC opening on the cell body when dendrites were mechanically stimulated,suggesting mechanical transmission from the dendritic integrinαV toα5 in the cell body during HC activation.In addition,HC function was compromised in vivo,as determined by utilizing an antibody blockingαV activation andα5-deficient osteocyte-specific knockout mice.Furthermore,inhibition of integrinαV activation,but not that ofα5,attenuated activation of the phosphoinositide 3-kinase(PI3K)-protein kinase B(AKT)signaling pathway upon mechanical loading,and the inhibition of PI3K/AKT activation blocked integrinα5 activation and HC opening.Moreover,HC opening was blocked only by an anti-integrinαV antibody at low but not high FSS levels,suggesting that dendriticαV is a more sensitive mechanosensor thanα5 for activating HCs.Together,these results reveal a new molecular mechanism of mechanotransduction involving the coordinated actions of integrins and PI3K/AKT in osteocytic dendritic processes and cell bodies that leads to HC opening and the release of key bone anabolic factors. | Manuel A.Riquelme Sumin Gu Rui Hua Jean X.Jiang | 2021 | Bone Research2021，9，1： | 7 |
| 20 | T cells promote the regeneration of neural precursor cells in the hippocampus of Alzheimer's disease mice显示文摘Alzheimer's disease is closely associated with disorders of neurogenesis in the brain, and growing evidence supports the involvement of immunological mechanisms in the development of the disease. However, at present, the role of T cells in neuronal regeneration in the brain is unknown. We injected amyloid-beta 1–42 peptide into the hippocampus of six BALB/c wild-type mice and six BALB/c-nude mice with T-cell immunodeficiency to establish an animal model of Alzheimer's disease. A further six mice of each genotype were injected with same volume of normal saline. Immunohistochemistry revealed that the number of regenerated neural progenitor cells in the hippocampus of BALB/c wild-type mice was significantly higher than that in BALB/c-nude mice. Quantitative fluorescence PCR assay showed that the expression levels of peripheral T cell-associated cytokines(interleukin-2, interferon-γ) and hippocampal microglia-related cytokines(interleukin-1β, tumor necrosis factor-α) correlated with the number of regenerated neural progenitor cells in the hippocampus. These results indicate that T cells promote hippocampal neurogenesis in Alzheimer's disease and T-cell immunodeficiency restricts neuronal regeneration in the hippocampus. The mechanism underlying the promotion of neuronal regeneration by T cells is mediated by an increased expression of peripheral T cells and central microglial cytokines in Alzheimer's disease mice. Our findings provide an experimental basis for understanding the role of T cells in Alzheimer's disease. | Jing Liu Yuxin Ma Sumin Tian Li Zhang Mengmeng Zhao Yaqiong Zhang Dachuan Xu | 2014 | Neural Regeneration Research2014，9，16： | 7 |
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