Insulin secretion is a complex and highly regulated process.Although much progress has been made in understanding the cellular mechanisms of insulin secretion and regulation,it remains unclear how conclusions from the...Insulin secretion is a complex and highly regulated process.Although much progress has been made in understanding the cellular mechanisms of insulin secretion and regulation,it remains unclear how conclusions from these studies apply to living animals.That few studies have been done to address these issues is largely due to the lack of suitable tools in detecting secretory events at high spatial and temporal resolution in vivo.When combined with genetically encoded biosensor,optical imaging is a powerful tool for visualization of molecular events in vivo.In this study,we generated a DNA construct encoding a secretory granule resident protein that is linked with two spectrally separate fluorescent proteins,a highly pH-sensitive green pHluorin on the intra-granular side and a red mCherry in the cytosol.Upon exocytosis of secretory granules,the dim pHluorin inside the acidic secretory granules became highly fluorescent outside the cells at neutral pH,while mCherry fluorescence remained constant in the process,thus allowing ratiometric quantification of insulin secretory events.Furthermore,mCherry fluorescence enabled tracking the movement of secretory granules in living cells.We validated this approach in insulin-secreting cells,and generated a transgenic mouse line expressing the optical sensor specifically in pancreaticβ-cells.The transgenic mice will be a useful tool for future investigations of molecular mechanism of insulin secretion in vitro and in vivo.展开更多
In order to predict the surge pressure caused in the horizontal well drilling process, a new simple and applicable method has been established. It is based on the general theory of hydrostatic drilling fluid mechanics...In order to predict the surge pressure caused in the horizontal well drilling process, a new simple and applicable method has been established. It is based on the general theory of hydrostatic drilling fluid mechanics, and specifically described the flowing physical model towards surge pressure in horizontal well annulus, taking the effect of string eccentricity on the flowing law of drilling fluid into consideration. According to the constitutive equation of casson-mode under one-dimensional steady flow and the equations of annular flow rate under different drill string working conditions, this paper introduced the flow rate computation models of axial laminar flow in eccentric annulus apply to horizontal well, of which the numerical model was calculated by the program called Mathematica, ultimately, a new model for surge pressure prediction towards each interval in horizontal well was put forward. Application examples indicated that it can solve questions easily and precisely, which presents important meaning of guidance to the safety control while horizontal well drilling.展开更多
Based on the fractal nature of pore size in sandstone and grindingbody within a certain range and the Andreasen equation in theory, using the optimization theory of traditional tem- porary plugging agent for reference...Based on the fractal nature of pore size in sandstone and grindingbody within a certain range and the Andreasen equation in theory, using the optimization theory of traditional tem- porary plugging agent for reference, we established a new temporary plugging method for reservoir protection. This new method emphasizes on the formulation and optimization of solid filling particles and softening particles. It is good in easy operation and strong applicability. Indoor experiments with the natural core from Hailaer area were conducted using this new method. Compared with traditional methods, the filtration reduced significantly and the permeability recovery was improved greatly, which verified the rationality of this new method.展开更多
There are few studies on the mechanism of redox status imbalance and intestinal dysfunction in intrauterine growth restricted(IUGR)newborn piglets.Here,we investigated the mechanism of jejunum dysfunction in weaned pi...There are few studies on the mechanism of redox status imbalance and intestinal dysfunction in intrauterine growth restricted(IUGR)newborn piglets.Here,we investigated the mechanism of jejunum dysfunction in weaned piglets with IUGR and the mechanism through which dimethylglycine sodium salt(DMG-Na)supplementation improving the imbalance of their redox status.In this work,a total of 10 normal birth weight(NBW)newborn piglets and 20 IUGR newborn piglets were obtained.After weaning at 21 d,they were assigned to 3 groups(n=10/group):NBW weaned piglets fed standard basal diets(NBWC);one IUGR weaned piglets fed standard basal diets(IUGRC);another IUGR weaned piglets from the same litter fed standard basal diets plus 0.1%DMG-Na(IUGRD).The piglets in these 3 groups were sacrificed at 49 d of age,and the blood and jejunum samples were collected immediately.The growth performance values in the IUGRC group were lower(P<0.05)than those in the NBWC group.Jejunum histomorphological parameters,inflammatory cytokines,and digestive enzyme activity as well as serum immunoglobulin were lower(P<0.05)in the IUGRC group than those in the NBWC group.Compared with these in the NBWC group,the redox status of serum,jejunum,and mitochondria and the expression levels of jejunum redox status-related,cell adhesion-related,and mitochondrial function-related genes and proteins were suppressed in the IUGRC group(P<0.05).However,compared with those in the IUGRC group,the growth performance values,jejunum histomorphological parameters,inflammatory cytokines,digestive enzyme activity,serum immunoglobulin,redox status of serum,jejunum,and mitochondria,and the expression levels of jejunum redox status-related,cell adhesion-related,and mitochondrial function-related genes and proteins were improved(P<0.05)in the IUGRD group.In conclusion,dietary DMG-Na supplementation alleviates redox status imbalance and intestinal dysfunction in IUGR weaned piglets mainly by activating the sirtuin 1(SIRT1)/peroxisome proliferatoractivated receptorgcoactivator-1a(PGC1a)pathway,thereby improving their unfavorable body state.展开更多
Background:Insufficient cerebral perfusion is suggested to play a role in the development of Alzheimer disease(AD).However,there is a lack of direct evidence indicating whether hypoperfusion causes or aggravates AD pa...Background:Insufficient cerebral perfusion is suggested to play a role in the development of Alzheimer disease(AD).However,there is a lack of direct evidence indicating whether hypoperfusion causes or aggravates AD pathology.We investigated the effect of chronic cerebral hypoperfusion on AD-related pathology in humans.Methods:We enrolled a group of cognitively normal patients(median age:64 years)with unilateral chronic cerebral hypoperfusion.Regions of interest with the most pronounced hypoperfusion changes were chosen in the hypoperfused region and were then mirrored in the contralateral hemisphere to create a control region with normal perfusion.11C-Pittsburgh compound-positron emission tomography standard uptake ratios and brain atrophy indices were calculated from the computed tomography images of each patient.Results:The median age of the 10 participants,consisting of 4 males and 6 females,was 64 years(47-76 years).We found that there were no differences in standard uptake ratios of the cortex(volume of interest[VOI]:P=0.721,region of interest[ROI]:P=0.241)and grey/white ratio(VOI:P=0.333,ROI:P=0.445)and brain atrophy indices(Bicaudate,Bifrontal,Evans,Cella,Cella media,and Ventricular index,P>0.05)between the hypoperfused regions and contralateral normally perfused regions in patients with unilateral chronic cerebral hypoperfusion.Conclusion:Our findings suggest that chronic hypoperfusion due to large vessel stenosis may not directly induce cerebralβ-amyloid deposition and neurodegeneration in humans.展开更多
Sex reversal,representing extraordinary sexual plasticity during the life cycle,not only triggers reproduction in animals but also affects reproductive and endocrine system-related diseases and cancers in humans.Sex r...Sex reversal,representing extraordinary sexual plasticity during the life cycle,not only triggers reproduction in animals but also affects reproductive and endocrine system-related diseases and cancers in humans.Sex reversal has been broadly reported in animals;however,an integrated resource hub of sex reversal information is still lacking.Here,we constructed a comprehensive database named ASER(Animal Sex Reversal)by integrating sex reversal-related data of 18 species from teleostei to mammalia.We systematically collected 40,018 published papers and mined the sex reversal-associated genes(SRGs),including their regulatory networks,from 1611 core papers.We annotated homologous genes and computed conservation scores for whole genomes across the 18 species.Furthermore,we collected available RNA-seq datasets and investigated the expression dynamics of SRGs during sex reversal or sex determination processes.In addition,we manually annotated 550 in situ hybridization(ISH),fluorescence in situ hybridization(FISH),and im-munohistochemistry(IHC)images of SRGs from the literature and described their spatial expression in the gonads.Collectively,ASER provides a unique and integrated resource for researchers to query and reuse organized data to explore the mechanisms and applications of SRGs in animal breeding and human health.The ASER database is publicly available at http://aser.ihb.ac.cn/.展开更多
Ning Jennifer Chang's book shines a new light on micro-history studies of modem China.In this carefully researched project,Chang presents a significant number of details about horse racing,greyhound racing,and jai...Ning Jennifer Chang's book shines a new light on micro-history studies of modem China.In this carefully researched project,Chang presents a significant number of details about horse racing,greyhound racing,and jai alai in modem Shanghai to her readers.展开更多
文摘Insulin secretion is a complex and highly regulated process.Although much progress has been made in understanding the cellular mechanisms of insulin secretion and regulation,it remains unclear how conclusions from these studies apply to living animals.That few studies have been done to address these issues is largely due to the lack of suitable tools in detecting secretory events at high spatial and temporal resolution in vivo.When combined with genetically encoded biosensor,optical imaging is a powerful tool for visualization of molecular events in vivo.In this study,we generated a DNA construct encoding a secretory granule resident protein that is linked with two spectrally separate fluorescent proteins,a highly pH-sensitive green pHluorin on the intra-granular side and a red mCherry in the cytosol.Upon exocytosis of secretory granules,the dim pHluorin inside the acidic secretory granules became highly fluorescent outside the cells at neutral pH,while mCherry fluorescence remained constant in the process,thus allowing ratiometric quantification of insulin secretory events.Furthermore,mCherry fluorescence enabled tracking the movement of secretory granules in living cells.We validated this approach in insulin-secreting cells,and generated a transgenic mouse line expressing the optical sensor specifically in pancreaticβ-cells.The transgenic mice will be a useful tool for future investigations of molecular mechanism of insulin secretion in vitro and in vivo.
文摘In order to predict the surge pressure caused in the horizontal well drilling process, a new simple and applicable method has been established. It is based on the general theory of hydrostatic drilling fluid mechanics, and specifically described the flowing physical model towards surge pressure in horizontal well annulus, taking the effect of string eccentricity on the flowing law of drilling fluid into consideration. According to the constitutive equation of casson-mode under one-dimensional steady flow and the equations of annular flow rate under different drill string working conditions, this paper introduced the flow rate computation models of axial laminar flow in eccentric annulus apply to horizontal well, of which the numerical model was calculated by the program called Mathematica, ultimately, a new model for surge pressure prediction towards each interval in horizontal well was put forward. Application examples indicated that it can solve questions easily and precisely, which presents important meaning of guidance to the safety control while horizontal well drilling.
文摘Based on the fractal nature of pore size in sandstone and grindingbody within a certain range and the Andreasen equation in theory, using the optimization theory of traditional tem- porary plugging agent for reference, we established a new temporary plugging method for reservoir protection. This new method emphasizes on the formulation and optimization of solid filling particles and softening particles. It is good in easy operation and strong applicability. Indoor experiments with the natural core from Hailaer area were conducted using this new method. Compared with traditional methods, the filtration reduced significantly and the permeability recovery was improved greatly, which verified the rationality of this new method.
基金National Key Research and Development Program of China(No.2018YFD0501101)the National Natural Science Foundation of China(No.31802094).
文摘There are few studies on the mechanism of redox status imbalance and intestinal dysfunction in intrauterine growth restricted(IUGR)newborn piglets.Here,we investigated the mechanism of jejunum dysfunction in weaned piglets with IUGR and the mechanism through which dimethylglycine sodium salt(DMG-Na)supplementation improving the imbalance of their redox status.In this work,a total of 10 normal birth weight(NBW)newborn piglets and 20 IUGR newborn piglets were obtained.After weaning at 21 d,they were assigned to 3 groups(n=10/group):NBW weaned piglets fed standard basal diets(NBWC);one IUGR weaned piglets fed standard basal diets(IUGRC);another IUGR weaned piglets from the same litter fed standard basal diets plus 0.1%DMG-Na(IUGRD).The piglets in these 3 groups were sacrificed at 49 d of age,and the blood and jejunum samples were collected immediately.The growth performance values in the IUGRC group were lower(P<0.05)than those in the NBWC group.Jejunum histomorphological parameters,inflammatory cytokines,and digestive enzyme activity as well as serum immunoglobulin were lower(P<0.05)in the IUGRC group than those in the NBWC group.Compared with these in the NBWC group,the redox status of serum,jejunum,and mitochondria and the expression levels of jejunum redox status-related,cell adhesion-related,and mitochondrial function-related genes and proteins were suppressed in the IUGRC group(P<0.05).However,compared with those in the IUGRC group,the growth performance values,jejunum histomorphological parameters,inflammatory cytokines,digestive enzyme activity,serum immunoglobulin,redox status of serum,jejunum,and mitochondria,and the expression levels of jejunum redox status-related,cell adhesion-related,and mitochondrial function-related genes and proteins were improved(P<0.05)in the IUGRD group.In conclusion,dietary DMG-Na supplementation alleviates redox status imbalance and intestinal dysfunction in IUGR weaned piglets mainly by activating the sirtuin 1(SIRT1)/peroxisome proliferatoractivated receptorgcoactivator-1a(PGC1a)pathway,thereby improving their unfavorable body state.
文摘Background:Insufficient cerebral perfusion is suggested to play a role in the development of Alzheimer disease(AD).However,there is a lack of direct evidence indicating whether hypoperfusion causes or aggravates AD pathology.We investigated the effect of chronic cerebral hypoperfusion on AD-related pathology in humans.Methods:We enrolled a group of cognitively normal patients(median age:64 years)with unilateral chronic cerebral hypoperfusion.Regions of interest with the most pronounced hypoperfusion changes were chosen in the hypoperfused region and were then mirrored in the contralateral hemisphere to create a control region with normal perfusion.11C-Pittsburgh compound-positron emission tomography standard uptake ratios and brain atrophy indices were calculated from the computed tomography images of each patient.Results:The median age of the 10 participants,consisting of 4 males and 6 females,was 64 years(47-76 years).We found that there were no differences in standard uptake ratios of the cortex(volume of interest[VOI]:P=0.721,region of interest[ROI]:P=0.241)and grey/white ratio(VOI:P=0.333,ROI:P=0.445)and brain atrophy indices(Bicaudate,Bifrontal,Evans,Cella,Cella media,and Ventricular index,P>0.05)between the hypoperfused regions and contralateral normally perfused regions in patients with unilateral chronic cerebral hypoperfusion.Conclusion:Our findings suggest that chronic hypoperfusion due to large vessel stenosis may not directly induce cerebralβ-amyloid deposition and neurodegeneration in humans.
基金supported by grants from the National Natural Science Foundation of China(Grant Nos.31922085,31872191 to DL,Grant No.31922039 to YZ)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDA24010108 to WH and DL)+1 种基金the China Agriculture Research System of Ministry of Finance(MOF)and Ministry of Agriculture and Rural Affairs(MARA)(Grant No.CARS-46 to WH)the Natural Science Foundation of Hubei Province,China(Grant No.2020CFA056 to DL,Grant No.2020CFA057 to YZ).
文摘Sex reversal,representing extraordinary sexual plasticity during the life cycle,not only triggers reproduction in animals but also affects reproductive and endocrine system-related diseases and cancers in humans.Sex reversal has been broadly reported in animals;however,an integrated resource hub of sex reversal information is still lacking.Here,we constructed a comprehensive database named ASER(Animal Sex Reversal)by integrating sex reversal-related data of 18 species from teleostei to mammalia.We systematically collected 40,018 published papers and mined the sex reversal-associated genes(SRGs),including their regulatory networks,from 1611 core papers.We annotated homologous genes and computed conservation scores for whole genomes across the 18 species.Furthermore,we collected available RNA-seq datasets and investigated the expression dynamics of SRGs during sex reversal or sex determination processes.In addition,we manually annotated 550 in situ hybridization(ISH),fluorescence in situ hybridization(FISH),and im-munohistochemistry(IHC)images of SRGs from the literature and described their spatial expression in the gonads.Collectively,ASER provides a unique and integrated resource for researchers to query and reuse organized data to explore the mechanisms and applications of SRGs in animal breeding and human health.The ASER database is publicly available at http://aser.ihb.ac.cn/.
文摘Ning Jennifer Chang's book shines a new light on micro-history studies of modem China.In this carefully researched project,Chang presents a significant number of details about horse racing,greyhound racing,and jai alai in modem Shanghai to her readers.