Colon cancer is one of the malignant tumors with high morbidity and mortality worldwide,and its etiology is closely related to high levels of hydrogen sulfide(H_(2)S).To date,H_(2)S-activated near-infrared(NIR)fluores...Colon cancer is one of the malignant tumors with high morbidity and mortality worldwide,and its etiology is closely related to high levels of hydrogen sulfide(H_(2)S).To date,H_(2)S-activated near-infrared(NIR)fluorescent(FL)probes with high tumor tropism are still scarce.In this work,we created a new NIR FL probes(Cy-DG)that enables colon cancer targeted imaging and rapid fecal optical analysis by introducing an H_(2)S-recognition moiety and two D-glucosamine fragments on the scaffold of QCy7.Cy-DG exhibits excellent properties,including specific"off-on"response toward H_(2)S,intense NIR emission at 703 nm,large Stokes shift(118 nm),and high sensitivity(limit of detection(LOD),0.48μmol/L).Notably,the presence of D-glucosamine allows Cy-DG to be preferentially taken up by cancer cells.After intravenous administration,Cy-DG was able to efficiently accumulate in a MC38 intestinal cancer model and sensitively detect endogenous H_(2)S in vivo,showing 5.94-fold higher fluorescence intensity in small tumors<5 mm.Furthermore,Cy-DG was successfully used to detect H_(2)S in feces samples from colon cancer-bearing mice.We believe that Cy-DG has great potential as a powerful diagnostic tool for H_(2)S-related disorder and stool examinations in the future.展开更多
In most arid and semi-arid regions of the world, domestic livestock and native wildlife share pastures, and their competition for forage and habitat is thought to be a serious conservation issue. Moreover, unmanaged g...In most arid and semi-arid regions of the world, domestic livestock and native wildlife share pastures, and their competition for forage and habitat is thought to be a serious conservation issue. Moreover, unmanaged grazing by livestock can cause the population decline in wild ungulates. The diet of an animal species is a determining aspect of its ecological niche, and investigating its diet has been one of the initial steps in basic ecology study of a new species. To get an approximate understanding of the interspecific food relationships of argali（Ovis ammon darwini） between sexes, and sympatric domestic sheep and goats, we compared the diet compositions and diet-overlaps among these herbivores, i.e., male argali, female argali, domestic sheep, and domestic goats in the Mengluoke Mountains of Xinjiang, China by using micro-histological fecal analysis. Female argali, male argali, domestic sheep and domestic goat primarily consumed forbs（43.31%±4.86%）, grass（36.02%±9.32%）, forbs（41.01%±9.18%）, and forbs（36.22%±10.61%）, respectively in warm season. All these animals consumed mostly shrubs（female argali： 36.47%±7.56%; male argali： 47.28%±10.75%; domestic sheep： 40.46%±9.56%; and domestic goats： 42.88%±9.34%, respectively） in cold season. The diet-overlaps were relatively high among all species in cold season with values ranging from 0.88 to 0.94. Furthermore, Schoener＇s index measured between each possible pair of 4 herbivores increased from the warm season to the cold season. The results illustrate that the high degree of diet-overlap of argali and domestic livestock（sheep and goat） may pose a threat to the survival of the argali in cold season. From the viewpoint of rangeland management and conservation of the endangered argali, the numbers of domestic sheep and goats should be limited in cold season to reduce food competition.展开更多
基金financial support from the National Natural Science Foundation of China(Nos.22422407,22174078)the Fundamental Research Funds for the Central Universities,Nankai University(No.020-63253156)support from the Doctoral Foundation Program of Henan University of Technology(No.2021BS035)。
文摘Colon cancer is one of the malignant tumors with high morbidity and mortality worldwide,and its etiology is closely related to high levels of hydrogen sulfide(H_(2)S).To date,H_(2)S-activated near-infrared(NIR)fluorescent(FL)probes with high tumor tropism are still scarce.In this work,we created a new NIR FL probes(Cy-DG)that enables colon cancer targeted imaging and rapid fecal optical analysis by introducing an H_(2)S-recognition moiety and two D-glucosamine fragments on the scaffold of QCy7.Cy-DG exhibits excellent properties,including specific"off-on"response toward H_(2)S,intense NIR emission at 703 nm,large Stokes shift(118 nm),and high sensitivity(limit of detection(LOD),0.48μmol/L).Notably,the presence of D-glucosamine allows Cy-DG to be preferentially taken up by cancer cells.After intravenous administration,Cy-DG was able to efficiently accumulate in a MC38 intestinal cancer model and sensitively detect endogenous H_(2)S in vivo,showing 5.94-fold higher fluorescence intensity in small tumors<5 mm.Furthermore,Cy-DG was successfully used to detect H_(2)S in feces samples from colon cancer-bearing mice.We believe that Cy-DG has great potential as a powerful diagnostic tool for H_(2)S-related disorder and stool examinations in the future.
基金supported by the National Key Research and Development Project of China (2016YFC0503307)the National Natural Science Foundation of China (31661143019,4151101357,U1303301)
文摘In most arid and semi-arid regions of the world, domestic livestock and native wildlife share pastures, and their competition for forage and habitat is thought to be a serious conservation issue. Moreover, unmanaged grazing by livestock can cause the population decline in wild ungulates. The diet of an animal species is a determining aspect of its ecological niche, and investigating its diet has been one of the initial steps in basic ecology study of a new species. To get an approximate understanding of the interspecific food relationships of argali（Ovis ammon darwini） between sexes, and sympatric domestic sheep and goats, we compared the diet compositions and diet-overlaps among these herbivores, i.e., male argali, female argali, domestic sheep, and domestic goats in the Mengluoke Mountains of Xinjiang, China by using micro-histological fecal analysis. Female argali, male argali, domestic sheep and domestic goat primarily consumed forbs（43.31%±4.86%）, grass（36.02%±9.32%）, forbs（41.01%±9.18%）, and forbs（36.22%±10.61%）, respectively in warm season. All these animals consumed mostly shrubs（female argali： 36.47%±7.56%; male argali： 47.28%±10.75%; domestic sheep： 40.46%±9.56%; and domestic goats： 42.88%±9.34%, respectively） in cold season. The diet-overlaps were relatively high among all species in cold season with values ranging from 0.88 to 0.94. Furthermore, Schoener＇s index measured between each possible pair of 4 herbivores increased from the warm season to the cold season. The results illustrate that the high degree of diet-overlap of argali and domestic livestock（sheep and goat） may pose a threat to the survival of the argali in cold season. From the viewpoint of rangeland management and conservation of the endangered argali, the numbers of domestic sheep and goats should be limited in cold season to reduce food competition.
