AIM: To investigate whether induction of tolerance of mice to lipopolysaccharide (LPS) was able to inhibit apoptotic reaction in terms of characteristic DNA fragmentation and protect mice from lethal effect. METHODS: ...AIM: To investigate whether induction of tolerance of mice to lipopolysaccharide (LPS) was able to inhibit apoptotic reaction in terms of characteristic DNA fragmentation and protect mice from lethal effect. METHODS: Experimental groups of mice were pretreated with non-lethal amount of LPS (0.05 μg). Both control and experimental groups simultaneously were challenged with LPS plus D-GaIN for 6-7 h. The evaluations of both DNA fragmentations from the livers and the protection efficacy against lethality to mice through induction of tolerance to LPS were conducted. RESULTS: In the naive mice challenge with LPS plus D-GaIN resulted in complete death in 24 h, whereas a characteristic apoptotic DNA fragmentation was exclusively seen in the livers of mice receiving LPS in combination with D-GaIN. The mortality in the affected mice was closely correlated to the onset of DNA fragmentation. By contrast, in the mice pre-exposed to LPS, both lethal effect and apoptotic DNA fragmentation were suppressed when challenged with LPS/D-GalN. In addition to LPS, the induction of mouse tolerance to TNF also enabled mice to cross-react against death and apoptotic DNA fragmentation when challenged with TNF and/or LPS in the presence of D-GaIN. Moreover, this protection effect by LPS could last up to 24 h. TNFR1 rather than TNFR2 played a dual role in signaling pathway of either induction of tolerance to LPS for the protection of mice from mortality or inducing morbidity leading to the death of mice. CONCLUSION: The mortality of D-GalN-treated mice in response to LPS was exceedingly correlated to the onset of apoptosis in the liver, which can be effectively suppressed by brief exposure of mice to a minute amount of LPS. The induced tolerance status was mediated not only by LPS but also by TNF. The developed tolerance to either LPS or TNF can be reciprocally cross-reacted between LPS and TNF challenges, whereas the signaling of induction of tolerance and promotion of apoptosis was through TNFR1, rather than TNFR2.展开更多
Objective: The aim of the study was to investigate the mechanism of gemcitabine (GEM) combination with radiation on the high metastasis human ovarian cancer cell line (HO-8910PM). Methods: Human ovarian cancer c...Objective: The aim of the study was to investigate the mechanism of gemcitabine (GEM) combination with radiation on the high metastasis human ovarian cancer cell line (HO-8910PM). Methods: Human ovarian cancer cell line HO- 8910PM was treated with different concentrations of gemcitabine for 24 h, then the cells were counted. In the study of GEM combination with radiation, an efficiency of colony formation was observed; the cell cycle and apoptosis were analyzed by flow cytometry; the experiment of depend on the time and its radio sensitivity were observed by using mitotic index with the cells for each 24, 48, 72 and 96 h after experiment. Results: It suggested that the GEM had an inhibition effect on the human ovarian cancer cell line. The alive cell numbers were decreased by following a height of GEM concentration. When GEM in combina- tion with a radiation, the suppression was significantly increased than that of single GEM therapy. The efficiency of colony formation was significantly lower, under this condition the cell could be arrested at G0-G1 phase and could be decreased to enter into the S phase; the apoptosis percentage could be significantly increased; especially, under the 4 Gy and 6 Gy doses the cell apoptosis was more obvious. GEM combination with radiation had depended on the time to the cells; mitotic index of the calls in combination group was observed significantly lower than that of single GEM therapy or single radiation, and this showed that it had an effect of radiosensitivity. Conclusion: The GEM has a significant growth inhibition on the human ovarian cancer cells, GEM combination with radiation could induce HO-8910PM cell occurred arrested and apoptosis. It has depended on the time and has a radiosensitivity effect. The result shows that it is a better method to treat the human ovarian cancer by using radiotherapy combined with gemcitabine.展开更多
On April 14, 2010 at 07:49 (Beijing time), a catastrophic earthquake with Ms 7. 1 occurred at the central Qinghai-Tibetan Plateau. The epicenter was located at Yushu county, Qinghai Province, China. A total of 2036...On April 14, 2010 at 07:49 (Beijing time), a catastrophic earthquake with Ms 7. 1 occurred at the central Qinghai-Tibetan Plateau. The epicenter was located at Yushu county, Qinghai Province, China. A total of 2036 landslides were determined from visual interpretation of aerial photographs and high resolution remote sensing images, and verified by selected field investigations. These landslides covered a total area of about 1. 194km~. Characteristics and failure mechanisms of these landslides are listed in this paper, including the fact that the spatial distribution of these landslides is controlled by co- seismic main surface fault ruptures. Most of the landslides were small scale, causing rather less hazards, and often occurring close to each other. The landslides were of various types, including mainly disrupted landslides and rock falls in shallows and also deep-seated landslides, liquefaction induced landslides, and compound landslides. In addition to strong ground shaking, which is the direct landslide triggering factor, geological, topographical, and human activity also have impact on the occurrence of earthquake triggered landslides. In this paper, five types of failure mechanisms related to the landslides are presented, namely, the excavated toes of slopes accompanied by strong ground shaking; surface water infiltration accompanied by strong ground shaking; co- seismic fault slipping accompanied by strong ground shaking; only strong ground shaking; and delayed occurrence of landslides due to snow melt or rainfall infiltration at sites where slopes were weakened by co-seismic ground shaking. Besides the main co-seismic surface ruptures, slope fissures were also delineated from visual interpretation of aerial photographs in high resolution. A total of 4814 slope fissures, with a total length up to 77. lkm, were finally mapped. These slope fissures are mainly distributed on the slopes located at the southeastern end of the main co-seismic surface rupture zone, an area subject to strong compression during the earthquake.展开更多
Laboratory and greenhouse studies were conducted to assess the allelopathic potential of 12 rice cultivars on barnyard grass. Polyethylene glycol (PEG) was used to determine the influence of osmotic potential on the...Laboratory and greenhouse studies were conducted to assess the allelopathic potential of 12 rice cultivars on barnyard grass. Polyethylene glycol (PEG) was used to determine the influence of osmotic potential on the bioassay materials. Effect of different concentrations of stem, root, and leaf extracts of rice cultivars on seed germination, radicle and primary shoot length of barnyard grass seedlings, and rate of respiration of root pieces were investigated in the laboratory experiments. Shoot height and dry weight of weed stands were studied in the greenhouse, Also total peroxidase activity, chlorophyll pigment and mitotic index were determined. Results indicated that, among rice cultivars, Mehr, Tarom-mahali, G3, Nemat, and Shahpasand caused the most inhibition effects on investigated factors. Amol-3 showed the least negative effects on growth of seedlings and stands of barnyard grass. In laboratory, the Mehr cultivar demonstrated the maximum inhibitory effects by reducing barnyard grass seed germination percentage (88%), radicle length (100%), primary shoot length (83%), and root respiration (85%) Cell division, expressed as mitotic index, was significantly reduced in the presence of rice aqueous extracts. Mehr cultivar had higher inhibitory effect on mitosis compared to Amol-3. In greenhouse, the same cultivar showed the maximum inhibitory effect by reducing barnyard grass height (45%) and dry weight (64%). With increase in extract concentration, the inhibitory effect increased. Leaf extract from rice plants was more effective compared with the root and stem extracts. Comparison of rice cultivars and PEG indicated that any reduction in germination and growth of barnyard grass using rice extract concentrations of 5% and 10% must have been the result of allelochemicals in the extracts. Lower extract concentrations showed a more pronounced inhibitory effect in the laboratory as compared to the greenhouse studies. These results suggest that rice leaf extracts may be a source of natural herbicide.展开更多
AMP-activated protein kinase (AMPK) is an energy sensor that couples the cellular energy state with basic biological processes. AMPK is thought to be linked with cell division although the underlying mechanisms rema...AMP-activated protein kinase (AMPK) is an energy sensor that couples the cellular energy state with basic biological processes. AMPK is thought to be linked with cell division although the underlying mechanisms remain largely unknown. Here, we show that AMPK functionally participates throughout cell division and that AMPK catalytic subunits, especially α2, are sequentially associated with separate mitotic apparatus. Using quantitative phosphoproteomics analysis, we found that the strong direct sub- strate KIF4A is phosphorylated by AMPK at Set801. Further analysis revealed that AMPK and Aurora B competitively phosphore- gulates KIF4A during mitotic phase due to overlapping recognition motifs, resulting in the elaborate phosphoregutation for KIF4A-dependent central spindle length control. Given the intrinsic energy-sensing function of AMPK, our study links the KIF4A- dependent control of central spindle length with cellular glucose stress.展开更多
The Drosophila homolog of schizophrenia susceptibility gene dysbindin(Ddysb)affects a range of behaviors through regulation of multiple neurotransmitter signals,including dopamine activity.To gain insights into mechan...The Drosophila homolog of schizophrenia susceptibility gene dysbindin(Ddysb)affects a range of behaviors through regulation of multiple neurotransmitter signals,including dopamine activity.To gain insights into mechanisms underlying Ddysb-dependent regulation of dopamine signal,we investigated interaction between Ddysb and Ebony,the Drosophilaβ-alanyl-monoamine synthase involved in dopamine recycling.We found that Ddysb was capable of regulating expression of Ebony in a bi-directional manner and its subcellular distribution.Such regulation is confined to glial cells.The expression level of ebony and its accumulation in glial soma depend positively on Ddysb activity,whereas its distribution in glial processes is bound to be reduced in response to any alterations of Ddysb from the normal control level,either an increase or decrease.An optimal binding ratio between Dysb and Ebony might contribute to such non-linear effects.Thus,Ddysb-dependent regulation of Ebony could be one of the mechanisms that mediate dopamine signal.展开更多
基金Supported by a fellowship (to Zhou B) from Max-Planck-Society, Germany, and partially supported by the National Key Basic ResearchDevelopment Program (973 Program) of China, No. 2002CB513006 (to Zhou B)
文摘AIM: To investigate whether induction of tolerance of mice to lipopolysaccharide (LPS) was able to inhibit apoptotic reaction in terms of characteristic DNA fragmentation and protect mice from lethal effect. METHODS: Experimental groups of mice were pretreated with non-lethal amount of LPS (0.05 μg). Both control and experimental groups simultaneously were challenged with LPS plus D-GaIN for 6-7 h. The evaluations of both DNA fragmentations from the livers and the protection efficacy against lethality to mice through induction of tolerance to LPS were conducted. RESULTS: In the naive mice challenge with LPS plus D-GaIN resulted in complete death in 24 h, whereas a characteristic apoptotic DNA fragmentation was exclusively seen in the livers of mice receiving LPS in combination with D-GaIN. The mortality in the affected mice was closely correlated to the onset of DNA fragmentation. By contrast, in the mice pre-exposed to LPS, both lethal effect and apoptotic DNA fragmentation were suppressed when challenged with LPS/D-GalN. In addition to LPS, the induction of mouse tolerance to TNF also enabled mice to cross-react against death and apoptotic DNA fragmentation when challenged with TNF and/or LPS in the presence of D-GaIN. Moreover, this protection effect by LPS could last up to 24 h. TNFR1 rather than TNFR2 played a dual role in signaling pathway of either induction of tolerance to LPS for the protection of mice from mortality or inducing morbidity leading to the death of mice. CONCLUSION: The mortality of D-GalN-treated mice in response to LPS was exceedingly correlated to the onset of apoptosis in the liver, which can be effectively suppressed by brief exposure of mice to a minute amount of LPS. The induced tolerance status was mediated not only by LPS but also by TNF. The developed tolerance to either LPS or TNF can be reciprocally cross-reacted between LPS and TNF challenges, whereas the signaling of induction of tolerance and promotion of apoptosis was through TNFR1, rather than TNFR2.
文摘Objective: The aim of the study was to investigate the mechanism of gemcitabine (GEM) combination with radiation on the high metastasis human ovarian cancer cell line (HO-8910PM). Methods: Human ovarian cancer cell line HO- 8910PM was treated with different concentrations of gemcitabine for 24 h, then the cells were counted. In the study of GEM combination with radiation, an efficiency of colony formation was observed; the cell cycle and apoptosis were analyzed by flow cytometry; the experiment of depend on the time and its radio sensitivity were observed by using mitotic index with the cells for each 24, 48, 72 and 96 h after experiment. Results: It suggested that the GEM had an inhibition effect on the human ovarian cancer cell line. The alive cell numbers were decreased by following a height of GEM concentration. When GEM in combina- tion with a radiation, the suppression was significantly increased than that of single GEM therapy. The efficiency of colony formation was significantly lower, under this condition the cell could be arrested at G0-G1 phase and could be decreased to enter into the S phase; the apoptosis percentage could be significantly increased; especially, under the 4 Gy and 6 Gy doses the cell apoptosis was more obvious. GEM combination with radiation had depended on the time to the cells; mitotic index of the calls in combination group was observed significantly lower than that of single GEM therapy or single radiation, and this showed that it had an effect of radiosensitivity. Conclusion: The GEM has a significant growth inhibition on the human ovarian cancer cells, GEM combination with radiation could induce HO-8910PM cell occurred arrested and apoptosis. It has depended on the time and has a radiosensitivity effect. The result shows that it is a better method to treat the human ovarian cancer by using radiotherapy combined with gemcitabine.
基金sponsored by the National Natural Science Foundation,China(40821160550),supported by the National Natural Science Foundation of China (41202235 )the Basic Scientific Fund of the Institute of Geology, China Earthquake Administration (IGCEA1215)
文摘On April 14, 2010 at 07:49 (Beijing time), a catastrophic earthquake with Ms 7. 1 occurred at the central Qinghai-Tibetan Plateau. The epicenter was located at Yushu county, Qinghai Province, China. A total of 2036 landslides were determined from visual interpretation of aerial photographs and high resolution remote sensing images, and verified by selected field investigations. These landslides covered a total area of about 1. 194km~. Characteristics and failure mechanisms of these landslides are listed in this paper, including the fact that the spatial distribution of these landslides is controlled by co- seismic main surface fault ruptures. Most of the landslides were small scale, causing rather less hazards, and often occurring close to each other. The landslides were of various types, including mainly disrupted landslides and rock falls in shallows and also deep-seated landslides, liquefaction induced landslides, and compound landslides. In addition to strong ground shaking, which is the direct landslide triggering factor, geological, topographical, and human activity also have impact on the occurrence of earthquake triggered landslides. In this paper, five types of failure mechanisms related to the landslides are presented, namely, the excavated toes of slopes accompanied by strong ground shaking; surface water infiltration accompanied by strong ground shaking; co- seismic fault slipping accompanied by strong ground shaking; only strong ground shaking; and delayed occurrence of landslides due to snow melt or rainfall infiltration at sites where slopes were weakened by co-seismic ground shaking. Besides the main co-seismic surface ruptures, slope fissures were also delineated from visual interpretation of aerial photographs in high resolution. A total of 4814 slope fissures, with a total length up to 77. lkm, were finally mapped. These slope fissures are mainly distributed on the slopes located at the southeastern end of the main co-seismic surface rupture zone, an area subject to strong compression during the earthquake.
文摘Laboratory and greenhouse studies were conducted to assess the allelopathic potential of 12 rice cultivars on barnyard grass. Polyethylene glycol (PEG) was used to determine the influence of osmotic potential on the bioassay materials. Effect of different concentrations of stem, root, and leaf extracts of rice cultivars on seed germination, radicle and primary shoot length of barnyard grass seedlings, and rate of respiration of root pieces were investigated in the laboratory experiments. Shoot height and dry weight of weed stands were studied in the greenhouse, Also total peroxidase activity, chlorophyll pigment and mitotic index were determined. Results indicated that, among rice cultivars, Mehr, Tarom-mahali, G3, Nemat, and Shahpasand caused the most inhibition effects on investigated factors. Amol-3 showed the least negative effects on growth of seedlings and stands of barnyard grass. In laboratory, the Mehr cultivar demonstrated the maximum inhibitory effects by reducing barnyard grass seed germination percentage (88%), radicle length (100%), primary shoot length (83%), and root respiration (85%) Cell division, expressed as mitotic index, was significantly reduced in the presence of rice aqueous extracts. Mehr cultivar had higher inhibitory effect on mitosis compared to Amol-3. In greenhouse, the same cultivar showed the maximum inhibitory effect by reducing barnyard grass height (45%) and dry weight (64%). With increase in extract concentration, the inhibitory effect increased. Leaf extract from rice plants was more effective compared with the root and stem extracts. Comparison of rice cultivars and PEG indicated that any reduction in germination and growth of barnyard grass using rice extract concentrations of 5% and 10% must have been the result of allelochemicals in the extracts. Lower extract concentrations showed a more pronounced inhibitory effect in the laboratory as compared to the greenhouse studies. These results suggest that rice leaf extracts may be a source of natural herbicide.
基金This work was supported by the National Natural Science Foundation of China (81673489), the State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences (SIMM1705ZZ-02), Institutes for Drug Discovery and Development, Chinese Academy of Sciences (CASIMM0120161001), and the Science and Technology Commission of Shanghai Municipality (16430724100 and 14431902800).
文摘AMP-activated protein kinase (AMPK) is an energy sensor that couples the cellular energy state with basic biological processes. AMPK is thought to be linked with cell division although the underlying mechanisms remain largely unknown. Here, we show that AMPK functionally participates throughout cell division and that AMPK catalytic subunits, especially α2, are sequentially associated with separate mitotic apparatus. Using quantitative phosphoproteomics analysis, we found that the strong direct sub- strate KIF4A is phosphorylated by AMPK at Set801. Further analysis revealed that AMPK and Aurora B competitively phosphore- gulates KIF4A during mitotic phase due to overlapping recognition motifs, resulting in the elaborate phosphoregutation for KIF4A-dependent central spindle length control. Given the intrinsic energy-sensing function of AMPK, our study links the KIF4A- dependent control of central spindle length with cellular glucose stress.
基金supported by the National Basic Research Program of Ministry of Science and Technology of China(2009CB941301 and 2013CB835102)the Tsinghua University Initiative Scientific Research Program(20111080956,all to Zhong Yi)+1 种基金the China Postdoctoral Science Foundation(2012M510412)supported by the Postdoctoral Fellowship at Tsinghua-Peking Center for Life Sciences
文摘The Drosophila homolog of schizophrenia susceptibility gene dysbindin(Ddysb)affects a range of behaviors through regulation of multiple neurotransmitter signals,including dopamine activity.To gain insights into mechanisms underlying Ddysb-dependent regulation of dopamine signal,we investigated interaction between Ddysb and Ebony,the Drosophilaβ-alanyl-monoamine synthase involved in dopamine recycling.We found that Ddysb was capable of regulating expression of Ebony in a bi-directional manner and its subcellular distribution.Such regulation is confined to glial cells.The expression level of ebony and its accumulation in glial soma depend positively on Ddysb activity,whereas its distribution in glial processes is bound to be reduced in response to any alterations of Ddysb from the normal control level,either an increase or decrease.An optimal binding ratio between Dysb and Ebony might contribute to such non-linear effects.Thus,Ddysb-dependent regulation of Ebony could be one of the mechanisms that mediate dopamine signal.