目的研究便秘型肠易激综合征(C-IBS)大鼠模型对直肠球囊扩张的内脏敏感性改变和肠神经系统及中枢神经系统5-羟色胺(5-HT)、c-fos的分布和异常表达。方法C-IBS大鼠模型组应用冰水灌胃方法建立(A组,n=10)和正常对照大鼠(B组,n=10)。所有...目的研究便秘型肠易激综合征(C-IBS)大鼠模型对直肠球囊扩张的内脏敏感性改变和肠神经系统及中枢神经系统5-羟色胺(5-HT)、c-fos的分布和异常表达。方法C-IBS大鼠模型组应用冰水灌胃方法建立(A组,n=10)和正常对照大鼠(B组,n=10)。所有大鼠给予直肠内球囊扩张,检测球囊扩张引起腹部收缩反射的最小容量阈值及1.0 mL扩张容量时腹部收缩反射(AWR)的次数。结肠、回盲部肌间神经丛及下丘脑、前扣带回5-HT和c-fos表达应用免疫组织化学染色及计算机图像分析系统半定量进行分析。结果直肠内球囊扩张时,A组引起腹部收缩的最小容量阈值略高于B组,无明显统计学差异(P>0.05),直肠球囊扩张体积1.0 mL时A组3 min AWR低于B组(10.3±3.3vs18.3±5.5,P<0.05)。A组结肠、回盲部5-HT、c-fos阳性肌间神经丛的数目及OD值均明显高于B组(P<0.05);A组下丘脑及前扣带回5-HT、c-fos阳性神经组织面积及OD值也明显高于B组。结论C-IBS大鼠模型存在对直肠球囊扩张的内脏敏感性异常,肠神经系统及中枢神经系统5-HT、c-fos的异常表达可能参与C-IBS大鼠内脏敏感性异常的调节。展开更多
目的:探讨便秘型肠易激综合征(C-IBS)大鼠模型对直肠球囊扩张的内脏敏感性改变和脊髓背角5-羟色胺(5-HT)、c-fos的分布和异常表达.方法:C-IBS大鼠模型组应用冰水ig方法建立(A组,n=10),和正常对照大鼠(B组,n=10).所有大鼠给予直肠内球囊...目的:探讨便秘型肠易激综合征(C-IBS)大鼠模型对直肠球囊扩张的内脏敏感性改变和脊髓背角5-羟色胺(5-HT)、c-fos的分布和异常表达.方法:C-IBS大鼠模型组应用冰水ig方法建立(A组,n=10),和正常对照大鼠(B组,n=10).所有大鼠给予直肠内球囊扩张,检测球囊扩张引起腹部收缩反射的最小容量阈值及球囊不同容量扩张时腹部收缩反射的次数.腰骶段脊髓背角5-HT和c-fos表达应用免疫组织化学染色及计算机图像分析系统半定量进行分析.结果:直肠内球囊扩张时,A组引起腹部收缩的最小容量阈值略高于B组,无明显统计学差并(0.59±0.09 vs 0.57±0.13,P>0.05).直肠球囊扩张体积1.0mL时A组腹部收缩反射次数低于B组(10.3±3.3 vs 18.3±5.5,P<0.05);体积1.5和2.0mL高容量扩张时两组无明显差异(P>0.05).A组腰骶段脊髓背角5-HT、c-fos阳性神经组织的面积均明显高于B组(5-HT面积:146.5±15.1 vs 109.3±18.5;5-HT OD:45826±2563.2 vs 29358±8965.5:c-fos面积:125.4±23.3 vs 88.7±23.2;c-fos OD:46258±4642 vs 33238±4587;均P<0.05).结论:C-IBS大鼠模型存在对直肠球囊扩张的内脏敏感性异常,脊髓背角5-HT、c-fos的异常表达可能参与C-IBS大鼠内脏敏感性异常的调节.展开更多
Machine learning algorithms are an important measure with which to perform landslide susceptibility assessments, but most studies use GIS-based classification methods to conduct susceptibility zonation.This study pres...Machine learning algorithms are an important measure with which to perform landslide susceptibility assessments, but most studies use GIS-based classification methods to conduct susceptibility zonation.This study presents a machine learning approach based on the C5.0 decision tree(DT) model and the K-means cluster algorithm to produce a regional landslide susceptibility map. Yanchang County, a typical landslide-prone area located in northwestern China, was taken as the area of interest to introduce the proposed application procedure. A landslide inventory containing 82 landslides was prepared and subsequently randomly partitioned into two subsets: training data(70% landslide pixels) and validation data(30% landslide pixels). Fourteen landslide influencing factors were considered in the input dataset and were used to calculate the landslide occurrence probability based on the C5.0 decision tree model.Susceptibility zonation was implemented according to the cut-off values calculated by the K-means cluster algorithm. The validation results of the model performance analysis showed that the AUC(area under the receiver operating characteristic(ROC) curve) of the proposed model was the highest, reaching 0.88,compared with traditional models(support vector machine(SVM) = 0.85, Bayesian network(BN) = 0.81,frequency ratio(FR) = 0.75, weight of evidence(WOE) = 0.76). The landslide frequency ratio and frequency density of the high susceptibility zones were 6.76/km^(2) and 0.88/km^(2), respectively, which were much higher than those of the low susceptibility zones. The top 20% interval of landslide occurrence probability contained 89% of the historical landslides but only accounted for 10.3% of the total area.Our results indicate that the distribution of high susceptibility zones was more focused without containing more " stable" pixels. Therefore, the obtained susceptibility map is suitable for application to landslide risk management practices.展开更多
Background Tubulointerstitial renal fibrosis is the common end point of progressive kidney diseases, and tubular epithelial-myofibroblast transdifferentiation （TEMT） plays a key role in the progress of tubulointerst...Background Tubulointerstitial renal fibrosis is the common end point of progressive kidney diseases, and tubular epithelial-myofibroblast transdifferentiation （TEMT） plays a key role in the progress of tubulointerstitial renal fibrosis. Anaphylatoxin C3a and C5a are identified as novel profibrotic factors in renal disease and as potential new therapeutic targets. The aim of this study was to investigate whether C3a, C5a can regulate TEMT by transforming growth factor-β1 （TGF-β1）/connective tissue growth factor （CTGF） signaling pathway and the effects of C3a and C5a receptor antagonists （C3aRA and C5aRA） on C3α- and C5α-induced TEMT. Methods HK-2 cells were divided into C3a and C5a groups which were subdivided into four subgroups： control group, 10 ng/ml TGF-I31 group, 50 nmol/L C3a group, 50 nmol/L C3a plus 1 pmol/L C3aRA group; control group, 10 ng/ml TGF-I^I group, 50 nmol/L C5a group, 50 nmol/L C5a plus 2.5 pmol/L C5aRA group. TGF-β1 receptor antagonist （TGF-β1 RA） 10 IJg/ml was used to investigate the mechanism of C3α- and C5α-induced TEMT. Electron microscopy was used to observe the morphological changes. Immunocytochemistry staining, real-time PCR and Western blotting were used to detect the expressions of a smooth muscle actin （α-SMA）, E-cadherin, Col-I, C3a receptor （C3aR）, C5aR, CTGF and TGF-β1. Results HK-2 cells cultured with C3a and C5a for 72 hours exhibited strong staining of α-SMA, lost the positive staining of E-cadherin, and showed a slightly spindle-like shape and loss of microvilli on the cell surface. The expressions of α-SMA, E-cadherin, Col-I, C3aR, C5aR, TGF-β1 and CTGF in C3α- and C5α-treated groups were higher than normal control group （P 〈0.05）. C3aRA and C5aRA inhibited the expressions of α-SMA, Col-I, C3aR, C5aR, and up-regulated the expression of E-cadherin （P 〈0.05）. TGF-β1 and CTGF mRNA expressions induced by C3a and C5a were partly blocked by TGF-β1 RA （P 〈0.05）. Conclusion C3a and C5a can induce TEMT via the up-regu展开更多
The 2 ℃ warming target has been used widely in global and regional climate change research. Previous studies have shown large uncertainties in the time when surface air temperature （SAT） change over China will reac...The 2 ℃ warming target has been used widely in global and regional climate change research. Previous studies have shown large uncertainties in the time when surface air temperature （SAT） change over China will reach 2℃ rela- tive to the pre-industrial era. To understand the uncertainties, we analyzed the projected SAT in the twenty-first century using 40 state-of-the-art climate models under two Repre- sentative Concentration Pathways （RCP4.5 and RCPS.5） from the Coupled Model Intercomparison Project Phase 5. The 2℃ threshold-crossing time （TCT） of SAT averaged across China was around 2033 and 2029 for RCP4.5 and RCP8.5, respectively. Considering a 4-1o- range of inter- model SAT change, the upper and lower bounds of the 2 ℃ TCT could differ by about 25 years or even more. Uncer- tainty in the projected SAT and the warming rate around the TCT are the two main factors responsible for the TCT uncertainty. The former is determined by the climate sensi- tivity represented by the global mean surface temperature response. About 45 % of the intermodel variance of the projected 2 ~C TCT for averaged SAT over China can be explained by climate sensitivity across the models, which is contributed mainly by central and southern China. In a cli- mate more sensitive to CO2 forcing, stronger greenhouse effect, less stratus cloud over the East Asian monsoon region, and less snow cover on the Tibetan Plateau result in increased downward longwave radiation, increased shortwave radia- tion, and decreased shortwave radiation reflected by the surface, respectively, all of which may advance the TCT.展开更多
文摘目的研究便秘型肠易激综合征(C-IBS)大鼠模型对直肠球囊扩张的内脏敏感性改变和肠神经系统及中枢神经系统5-羟色胺(5-HT)、c-fos的分布和异常表达。方法C-IBS大鼠模型组应用冰水灌胃方法建立(A组,n=10)和正常对照大鼠(B组,n=10)。所有大鼠给予直肠内球囊扩张,检测球囊扩张引起腹部收缩反射的最小容量阈值及1.0 mL扩张容量时腹部收缩反射(AWR)的次数。结肠、回盲部肌间神经丛及下丘脑、前扣带回5-HT和c-fos表达应用免疫组织化学染色及计算机图像分析系统半定量进行分析。结果直肠内球囊扩张时,A组引起腹部收缩的最小容量阈值略高于B组,无明显统计学差异(P>0.05),直肠球囊扩张体积1.0 mL时A组3 min AWR低于B组(10.3±3.3vs18.3±5.5,P<0.05)。A组结肠、回盲部5-HT、c-fos阳性肌间神经丛的数目及OD值均明显高于B组(P<0.05);A组下丘脑及前扣带回5-HT、c-fos阳性神经组织面积及OD值也明显高于B组。结论C-IBS大鼠模型存在对直肠球囊扩张的内脏敏感性异常,肠神经系统及中枢神经系统5-HT、c-fos的异常表达可能参与C-IBS大鼠内脏敏感性异常的调节。
文摘目的:探讨便秘型肠易激综合征(C-IBS)大鼠模型对直肠球囊扩张的内脏敏感性改变和脊髓背角5-羟色胺(5-HT)、c-fos的分布和异常表达.方法:C-IBS大鼠模型组应用冰水ig方法建立(A组,n=10),和正常对照大鼠(B组,n=10).所有大鼠给予直肠内球囊扩张,检测球囊扩张引起腹部收缩反射的最小容量阈值及球囊不同容量扩张时腹部收缩反射的次数.腰骶段脊髓背角5-HT和c-fos表达应用免疫组织化学染色及计算机图像分析系统半定量进行分析.结果:直肠内球囊扩张时,A组引起腹部收缩的最小容量阈值略高于B组,无明显统计学差并(0.59±0.09 vs 0.57±0.13,P>0.05).直肠球囊扩张体积1.0mL时A组腹部收缩反射次数低于B组(10.3±3.3 vs 18.3±5.5,P<0.05);体积1.5和2.0mL高容量扩张时两组无明显差异(P>0.05).A组腰骶段脊髓背角5-HT、c-fos阳性神经组织的面积均明显高于B组(5-HT面积:146.5±15.1 vs 109.3±18.5;5-HT OD:45826±2563.2 vs 29358±8965.5:c-fos面积:125.4±23.3 vs 88.7±23.2;c-fos OD:46258±4642 vs 33238±4587;均P<0.05).结论:C-IBS大鼠模型存在对直肠球囊扩张的内脏敏感性异常,脊髓背角5-HT、c-fos的异常表达可能参与C-IBS大鼠内脏敏感性异常的调节.
基金This research is funded by the National Natural Science Foundation of China(Grant Nos.41807285 and 51679117)Key Project of the State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(SKLGP2019Z002)+3 种基金the National Science Foundation of Jiangxi Province,China(20192BAB216034)the China Postdoctoral Science Foundation(2019M652287 and 2020T130274)the Jiangxi Provincial Postdoctoral Science Foundation(2019KY08)Fundamental Research Funds for National Universities,China University of Geosciences(Wuhan)。
文摘Machine learning algorithms are an important measure with which to perform landslide susceptibility assessments, but most studies use GIS-based classification methods to conduct susceptibility zonation.This study presents a machine learning approach based on the C5.0 decision tree(DT) model and the K-means cluster algorithm to produce a regional landslide susceptibility map. Yanchang County, a typical landslide-prone area located in northwestern China, was taken as the area of interest to introduce the proposed application procedure. A landslide inventory containing 82 landslides was prepared and subsequently randomly partitioned into two subsets: training data(70% landslide pixels) and validation data(30% landslide pixels). Fourteen landslide influencing factors were considered in the input dataset and were used to calculate the landslide occurrence probability based on the C5.0 decision tree model.Susceptibility zonation was implemented according to the cut-off values calculated by the K-means cluster algorithm. The validation results of the model performance analysis showed that the AUC(area under the receiver operating characteristic(ROC) curve) of the proposed model was the highest, reaching 0.88,compared with traditional models(support vector machine(SVM) = 0.85, Bayesian network(BN) = 0.81,frequency ratio(FR) = 0.75, weight of evidence(WOE) = 0.76). The landslide frequency ratio and frequency density of the high susceptibility zones were 6.76/km^(2) and 0.88/km^(2), respectively, which were much higher than those of the low susceptibility zones. The top 20% interval of landslide occurrence probability contained 89% of the historical landslides but only accounted for 10.3% of the total area.Our results indicate that the distribution of high susceptibility zones was more focused without containing more " stable" pixels. Therefore, the obtained susceptibility map is suitable for application to landslide risk management practices.
基金This research was supported by the grants from the National Natural Science Foundation of China，the Science and Technology Research Projects of Sichuan Province
文摘Background Tubulointerstitial renal fibrosis is the common end point of progressive kidney diseases, and tubular epithelial-myofibroblast transdifferentiation （TEMT） plays a key role in the progress of tubulointerstitial renal fibrosis. Anaphylatoxin C3a and C5a are identified as novel profibrotic factors in renal disease and as potential new therapeutic targets. The aim of this study was to investigate whether C3a, C5a can regulate TEMT by transforming growth factor-β1 （TGF-β1）/connective tissue growth factor （CTGF） signaling pathway and the effects of C3a and C5a receptor antagonists （C3aRA and C5aRA） on C3α- and C5α-induced TEMT. Methods HK-2 cells were divided into C3a and C5a groups which were subdivided into four subgroups： control group, 10 ng/ml TGF-I31 group, 50 nmol/L C3a group, 50 nmol/L C3a plus 1 pmol/L C3aRA group; control group, 10 ng/ml TGF-I^I group, 50 nmol/L C5a group, 50 nmol/L C5a plus 2.5 pmol/L C5aRA group. TGF-β1 receptor antagonist （TGF-β1 RA） 10 IJg/ml was used to investigate the mechanism of C3α- and C5α-induced TEMT. Electron microscopy was used to observe the morphological changes. Immunocytochemistry staining, real-time PCR and Western blotting were used to detect the expressions of a smooth muscle actin （α-SMA）, E-cadherin, Col-I, C3a receptor （C3aR）, C5aR, CTGF and TGF-β1. Results HK-2 cells cultured with C3a and C5a for 72 hours exhibited strong staining of α-SMA, lost the positive staining of E-cadherin, and showed a slightly spindle-like shape and loss of microvilli on the cell surface. The expressions of α-SMA, E-cadherin, Col-I, C3aR, C5aR, TGF-β1 and CTGF in C3α- and C5α-treated groups were higher than normal control group （P 〈0.05）. C3aRA and C5aRA inhibited the expressions of α-SMA, Col-I, C3aR, C5aR, and up-regulated the expression of E-cadherin （P 〈0.05）. TGF-β1 and CTGF mRNA expressions induced by C3a and C5a were partly blocked by TGF-β1 RA （P 〈0.05）. Conclusion C3a and C5a can induce TEMT via the up-regu
基金supported jointly by the ‘‘Strategic Priority Research Program–Climate Change: Carbon Budget and Related Issues’’ of the Chinese Academy of Sciences (XDA05110300)the Research Fund for Commonwealth Trades (Meteorology) (GYHY201506012)+1 种基金the National Natural Science Foundation of China (41420104006)the China Postdoctoral Science Foundation (2015M581152)
文摘The 2 ℃ warming target has been used widely in global and regional climate change research. Previous studies have shown large uncertainties in the time when surface air temperature （SAT） change over China will reach 2℃ rela- tive to the pre-industrial era. To understand the uncertainties, we analyzed the projected SAT in the twenty-first century using 40 state-of-the-art climate models under two Repre- sentative Concentration Pathways （RCP4.5 and RCPS.5） from the Coupled Model Intercomparison Project Phase 5. The 2℃ threshold-crossing time （TCT） of SAT averaged across China was around 2033 and 2029 for RCP4.5 and RCP8.5, respectively. Considering a 4-1o- range of inter- model SAT change, the upper and lower bounds of the 2 ℃ TCT could differ by about 25 years or even more. Uncer- tainty in the projected SAT and the warming rate around the TCT are the two main factors responsible for the TCT uncertainty. The former is determined by the climate sensi- tivity represented by the global mean surface temperature response. About 45 % of the intermodel variance of the projected 2 ~C TCT for averaged SAT over China can be explained by climate sensitivity across the models, which is contributed mainly by central and southern China. In a cli- mate more sensitive to CO2 forcing, stronger greenhouse effect, less stratus cloud over the East Asian monsoon region, and less snow cover on the Tibetan Plateau result in increased downward longwave radiation, increased shortwave radia- tion, and decreased shortwave radiation reflected by the surface, respectively, all of which may advance the TCT.
