AIM: TO investigate the growth suppression of adenovirus expressing p27^kip1 on established esophageal tumors in nude mice. METHODS: Esophageal carcinoma xenografts in nude mice were established by tumor tissue mass...AIM: TO investigate the growth suppression of adenovirus expressing p27^kip1 on established esophageal tumors in nude mice. METHODS: Esophageal carcinoma xenografts in nude mice were established by tumor tissue mass transplantation. The successfully constructed recombinant adenoviral vectors carrying p2^kip1 gene (Ad- p27^%kip1) were directly injected into the esophageal tumors in nude mice. Compared to control group, the growth curve of tumor was drawn and the growth inhibition rate of tumor was calculated. The histology of tumors was examined by hematoxylin and eosin (H&E) staining. The expression of p27^kip1 and survivin was detected in tumors by immunohistochemical technique. RESULTS: The growth of tumors in gene therapy group with Ad-p27^kip1 was obviously suppressed compared to control group (0.42±0.08 g vs 1.17±0.30 g, t=6.39, P〈0.01), the inhibition rate of tumor growth reached 64.1%. Pathological detection showed that the tumors in nude mice were poorly differentiated esophageal squarnous carcinoma. In addition, the expression of p27^kip1 was increased, while the expression of survivin was decreased in tumors after being transfected with Ad-p27^kip1. CONCLUSION: p27^kip1 gene therapy mediated by adenovirus vector has a significant inhibitory effect on esophageal carcinoma in vivo. Up-regulated p27^kip1 expression and down-regulated survivin expression may be its important mechanisms.展开更多
Indoor smog chamber experiments have been conducted to investigate the dynamics of sec- ondary organic aerosol (SOA) formation from OH-initiated photo-oxidation of isoprene in the presence of organic seed aerosol. T...Indoor smog chamber experiments have been conducted to investigate the dynamics of sec- ondary organic aerosol (SOA) formation from OH-initiated photo-oxidation of isoprene in the presence of organic seed aerosol. The dependence of the size distributions of SOA on both the level of pre-existing particles generated in situ from the photo-oxidation of trace hydrocarbons of indoor atmosphere and the concentration of precursor, has been investi- gated. It was shown that in the presence of high-level seed aerosol and low-level isoprene (typical urban atmospheric conditions), particle growth due to condensation of secondary organic products on pre-existing particles dominated; while in the presence of low-level seed aerosol and comparatively high-level isoprene (typical atmospheric conditions in rural re-gion), bimodal structures appeared in the size distributions of SOA, which corresponded to new particle formation resulting from homogeneous nucleation and particle growth due to condensation of secondary organic products on the per-existing particles respectively. The effects of concentrations of organic seed particles on SOA were also investigated. The particle size distributions evolutions as well as the corresponding formation rates of new particles in different conditions were also estimated.展开更多
AIM: To study the antitumor effect of Chinese compound Jinlongshe (JLS) granules on sarcoma 180 and MKN-45 human gastric cancer cell lines in vivo and its mechanism. METHODS: After establishment of S180 sarcoma (...AIM: To study the antitumor effect of Chinese compound Jinlongshe (JLS) granules on sarcoma 180 and MKN-45 human gastric cancer cell lines in vivo and its mechanism. METHODS: After establishment of S180 sarcoma (S180) and MKN-45 gastric cancer model of nude mice, the tumor-bearing mice were divided into 5 groups at random. Three experimental groups were respectively given the aqueous extract of JLS granules at doses of 120 g, 60 g and 20 g/(kg per 6/wk,i.g) for 3 wk in S180 and 6 wk in nude mice model. Positive control was given cyclophosphamide (Cy) at a dose of 50 mg/(kg per 3/wk, i.g) for 3 wk in S180 models and 5-Fluorouracil (5-FU) 20 mg/(kg per 3/wk, i.g) for 3 wk in nude mice model. Negative control was given normal saline (NS) at a dose of 0.18 g/(kg per 6/wk, i.g) respectively. After 3 wk in mice bearing S180 tumor and 6 wk in nude mice model, the experimental animals were sacrificed and the masses of tumor were weighed, and the rates of tumor inhibition of each treated group were calculated respectively. To determine the antitumor mechanisms, the morphological changes, cell cycle and apoptosis were observed in MKN-45 nude mice model. Annexin V-FITC/PI double staining FCM assay was used to further determine the live cells, apoptotic cells, necrotic cells and debris. RESULTS: The inhibitory rates of JLS granules at the doses of 20 g/kg, 60 g/kg and 120 g/kg were 50.31%, 55.94% and 68.13% (P 〈 0.01) in nude mice models and 40.90%, 50.32% and 58.46% (P 〈 0.01) in S180 model. The inhibitory rate of Cy was 85.22% in S180 models and the inhibitory rate of 5-FU was 53.43% in nude mice model (P 〈 0.01). Nuclear chromatin and margination were observed under a transmission electron microscope (TEM). The G0/G1 phase was arrested, typical apoptotic peak appeared, the apoptotic rate was 22.81%-38.54% in three JLS granule-treated groups. Annexin V-FITC/PI double staining FCM assay showed that the apoptotic cells were 4.36%, 3.08% and 7.08% in three dosages, most cells were localized in the low right quadrant. CONCLUSION:Jinlongshe granules possess anti-tumor effects on experimental tumor models in vivo, and apoptosis induction is one of its anti-tumor mechanisms.展开更多
The correlation coefficients and scattering were studied in Ki and new inbred lines for phytic acid (PA) and inorganic phosphorus content (InP) content in seeds of tropical maize (Zea mays L.). The understanding...The correlation coefficients and scattering were studied in Ki and new inbred lines for phytic acid (PA) and inorganic phosphorus content (InP) content in seeds of tropical maize (Zea mays L.). The understanding of the variability in PA and InP characters would be useful in a breeding program. A total of 16 Ki and 25 new inbred lines of tropical maize were planted in Completely Randomized Design (CRD) during late rainy season, 2007 to early rainy season, 2009 at Inseechandrastitya Institute for Crops Research and Development, Thailand. The result showed low correlation with no statistical significant between PA and InP contents in corn seeds performed either in different sources of inbred lines or years. For PA content, most of inbred lines were skewed toward high PA (〉 900 mg/100 g) both in Ki and new inbred lines in every year. The lowest PA value found in Ki inbred lines both in two years were Ki10, Ki15, Ki20, and Ki52.30A10-S11-43-1-3 was the lowest PA inbred lines observing in two years in new germplasm.展开更多
Why do two sexes of the same species differ in body size holds a long-standing question of evolutionary biology. While many across-species comparisons have focused on ultimate causes behind sexual size dimorphism (SS...Why do two sexes of the same species differ in body size holds a long-standing question of evolutionary biology. While many across-species comparisons have focused on ultimate causes behind sexual size dimorphism (SSD), only have a few been directed toward elucidating its ontogenetic basis. Urodeles are an amphibian group in which the direction and degree of SSD vary greatly among species. Using demographic data yielded by skeletochronology for 33 urodele species, the current study re- veals a positive across-species correlation between SSD and the sex difference in mean age of adult animals, and the latter in- creases with the corresponding difference in age at maturity; annual growth rate does not differ between the sexes. We conclude that extended longevities in one sex, which is mediated by delayed maturation, would allow it to grow for longer and get larger, with growth rate making a weak contribution to body size. The sex-specific divergence in ontogenetic trajectory might be ex- plained by potentially high growth costs of reproduction to females in association with stronger fecundity selection, and to males that are expected to experience stronger sexual selection [Current Zoology 59 (1): 142-150, 2013].展开更多
Aims Understanding the patterns and drivers of carbon isotope discrimination(13Δ)in C_(3)and C_(4)functional groups is critical for predicting C_(3)/C_(4)vegetation ratio from the isotopic composition of soil organic...Aims Understanding the patterns and drivers of carbon isotope discrimination(13Δ)in C_(3)and C_(4)functional groups is critical for predicting C_(3)/C_(4)vegetation ratio from the isotopic composition of soil organic matter.In this study,we aimed to evaluate how intraspecific variation will modify functional group-level 13Δvalues and the associated prediction of C_(3)/C_(4)vegetation ratio.Methods We investigated 13Δof 726 individual plants(96 species;C_(3)and C_(4)functional groups)and topsoil organic matter in 26 grassland communities along an aridity gradient in northern China.The fraction of C_(4)contribution was calculated with mixing models that considered:(i)both intra-and interspecific effects on the 13Δvalues of C_(3)and C_(4)functional groups;(ii)only interspecific effects;or(iii)none of these effects.Important Findings We found divergent responses of plant 13Δat the intraspecific level to the changes of aridity across the gradient.The 13Δof both C_(3)and C_(4)functional groups was negatively correlated with an aridity index,with higher sensitivity for C_(3)than for C_(4)functional groups.Intraspecific 13Δvariation played a key role in driving the total 13Δvariations of C_(3)plants.Overlooking such intraspecific effect in mixing models led to a greatly increased fraction of C_(4)contribution to soil organic carbon.A correction for the effects of intraspecific variation is therefore essential for correctly inferring C_(3)/C_(4)vegetation ratio in the past.Our findings provide basic information for the reconstruction of past vegetation change from bulk materials in arid and semiarid biomes.展开更多
Understanding how diaspore(hereafter‘seed’)morphology and orientation affect secondary seed dispersal by wind is important to link seed dispersal and post-dispersal processes,such as seed lodging,predation and germi...Understanding how diaspore(hereafter‘seed’)morphology and orientation affect secondary seed dispersal by wind is important to link seed dispersal and post-dispersal processes,such as seed lodging,predation and germination.This study aims to describe the effects of seed morphology and orientation on secondary seed dispersal by wind via mechanistic modelling.We extend the mechanistic model of Schurr et al.(2005)in order to describe how secondary seed dispersal by wind is affected by wind conditions,ground surface,seed morphology and orientation.The model simulates the initial landing orientations,dispersal distances and stopping orientations of individual seeds.To parameterize the model,we measured orientation-specific vertical seed projection and seed lift-off velocity(the wind speed at which a seed starts moving on the ground)of the asymmetric seeds of heterocarpous Zygophyllum xanthoxylon,and determined orientation-specific model parameters that depend on properties of seeds and/or the environment.To validate the model,we conducted wind channel experiments in which we released seeds of Z.xanthoxylon onto a sand-coated tar paper,and recorded the initial landing orientations,dispersal distances and stopping orientations of the seeds.The extended model could precisely predict secondary dispersal distance,and explain up to 99%of variation in the observed proportions of seeds which stopped in various orientations.The model predicts that secondary dispersal distance increases with wind speed and decreases with aerodynamic roughness length,and that there might be a positive correlation between dispersal distance and germination success.展开更多
文摘AIM: TO investigate the growth suppression of adenovirus expressing p27^kip1 on established esophageal tumors in nude mice. METHODS: Esophageal carcinoma xenografts in nude mice were established by tumor tissue mass transplantation. The successfully constructed recombinant adenoviral vectors carrying p2^kip1 gene (Ad- p27^%kip1) were directly injected into the esophageal tumors in nude mice. Compared to control group, the growth curve of tumor was drawn and the growth inhibition rate of tumor was calculated. The histology of tumors was examined by hematoxylin and eosin (H&E) staining. The expression of p27^kip1 and survivin was detected in tumors by immunohistochemical technique. RESULTS: The growth of tumors in gene therapy group with Ad-p27^kip1 was obviously suppressed compared to control group (0.42±0.08 g vs 1.17±0.30 g, t=6.39, P〈0.01), the inhibition rate of tumor growth reached 64.1%. Pathological detection showed that the tumors in nude mice were poorly differentiated esophageal squarnous carcinoma. In addition, the expression of p27^kip1 was increased, while the expression of survivin was decreased in tumors after being transfected with Ad-p27^kip1. CONCLUSION: p27^kip1 gene therapy mediated by adenovirus vector has a significant inhibitory effect on esophageal carcinoma in vivo. Up-regulated p27^kip1 expression and down-regulated survivin expression may be its important mechanisms.
文摘Indoor smog chamber experiments have been conducted to investigate the dynamics of sec- ondary organic aerosol (SOA) formation from OH-initiated photo-oxidation of isoprene in the presence of organic seed aerosol. The dependence of the size distributions of SOA on both the level of pre-existing particles generated in situ from the photo-oxidation of trace hydrocarbons of indoor atmosphere and the concentration of precursor, has been investi- gated. It was shown that in the presence of high-level seed aerosol and low-level isoprene (typical urban atmospheric conditions), particle growth due to condensation of secondary organic products on pre-existing particles dominated; while in the presence of low-level seed aerosol and comparatively high-level isoprene (typical atmospheric conditions in rural re-gion), bimodal structures appeared in the size distributions of SOA, which corresponded to new particle formation resulting from homogeneous nucleation and particle growth due to condensation of secondary organic products on the per-existing particles respectively. The effects of concentrations of organic seed particles on SOA were also investigated. The particle size distributions evolutions as well as the corresponding formation rates of new particles in different conditions were also estimated.
基金Supported by the Modernization Programs of Chinese Materia Medica of Science and Technology Commission Foundation of Shanghai, No. 04DZ19811
文摘AIM: To study the antitumor effect of Chinese compound Jinlongshe (JLS) granules on sarcoma 180 and MKN-45 human gastric cancer cell lines in vivo and its mechanism. METHODS: After establishment of S180 sarcoma (S180) and MKN-45 gastric cancer model of nude mice, the tumor-bearing mice were divided into 5 groups at random. Three experimental groups were respectively given the aqueous extract of JLS granules at doses of 120 g, 60 g and 20 g/(kg per 6/wk,i.g) for 3 wk in S180 and 6 wk in nude mice model. Positive control was given cyclophosphamide (Cy) at a dose of 50 mg/(kg per 3/wk, i.g) for 3 wk in S180 models and 5-Fluorouracil (5-FU) 20 mg/(kg per 3/wk, i.g) for 3 wk in nude mice model. Negative control was given normal saline (NS) at a dose of 0.18 g/(kg per 6/wk, i.g) respectively. After 3 wk in mice bearing S180 tumor and 6 wk in nude mice model, the experimental animals were sacrificed and the masses of tumor were weighed, and the rates of tumor inhibition of each treated group were calculated respectively. To determine the antitumor mechanisms, the morphological changes, cell cycle and apoptosis were observed in MKN-45 nude mice model. Annexin V-FITC/PI double staining FCM assay was used to further determine the live cells, apoptotic cells, necrotic cells and debris. RESULTS: The inhibitory rates of JLS granules at the doses of 20 g/kg, 60 g/kg and 120 g/kg were 50.31%, 55.94% and 68.13% (P 〈 0.01) in nude mice models and 40.90%, 50.32% and 58.46% (P 〈 0.01) in S180 model. The inhibitory rate of Cy was 85.22% in S180 models and the inhibitory rate of 5-FU was 53.43% in nude mice model (P 〈 0.01). Nuclear chromatin and margination were observed under a transmission electron microscope (TEM). The G0/G1 phase was arrested, typical apoptotic peak appeared, the apoptotic rate was 22.81%-38.54% in three JLS granule-treated groups. Annexin V-FITC/PI double staining FCM assay showed that the apoptotic cells were 4.36%, 3.08% and 7.08% in three dosages, most cells were localized in the low right quadrant. CONCLUSION:Jinlongshe granules possess anti-tumor effects on experimental tumor models in vivo, and apoptosis induction is one of its anti-tumor mechanisms.
文摘The correlation coefficients and scattering were studied in Ki and new inbred lines for phytic acid (PA) and inorganic phosphorus content (InP) content in seeds of tropical maize (Zea mays L.). The understanding of the variability in PA and InP characters would be useful in a breeding program. A total of 16 Ki and 25 new inbred lines of tropical maize were planted in Completely Randomized Design (CRD) during late rainy season, 2007 to early rainy season, 2009 at Inseechandrastitya Institute for Crops Research and Development, Thailand. The result showed low correlation with no statistical significant between PA and InP contents in corn seeds performed either in different sources of inbred lines or years. For PA content, most of inbred lines were skewed toward high PA (〉 900 mg/100 g) both in Ki and new inbred lines in every year. The lowest PA value found in Ki inbred lines both in two years were Ki10, Ki15, Ki20, and Ki52.30A10-S11-43-1-3 was the lowest PA inbred lines observing in two years in new germplasm.
文摘Why do two sexes of the same species differ in body size holds a long-standing question of evolutionary biology. While many across-species comparisons have focused on ultimate causes behind sexual size dimorphism (SSD), only have a few been directed toward elucidating its ontogenetic basis. Urodeles are an amphibian group in which the direction and degree of SSD vary greatly among species. Using demographic data yielded by skeletochronology for 33 urodele species, the current study re- veals a positive across-species correlation between SSD and the sex difference in mean age of adult animals, and the latter in- creases with the corresponding difference in age at maturity; annual growth rate does not differ between the sexes. We conclude that extended longevities in one sex, which is mediated by delayed maturation, would allow it to grow for longer and get larger, with growth rate making a weak contribution to body size. The sex-specific divergence in ontogenetic trajectory might be ex- plained by potentially high growth costs of reproduction to females in association with stronger fecundity selection, and to males that are expected to experience stronger sexual selection [Current Zoology 59 (1): 142-150, 2013].
基金This work was supported by the National Natural Science Foundation of China(31971465,31822006,31770503,41807108)National Basic Research Program of China(2016YFC0500601,2016YFC0500700)+1 种基金Youth Innovation Promotion Association CAS(201832,2020199)the Key Research Program from CAS(KFZD-SW-305-002).
文摘Aims Understanding the patterns and drivers of carbon isotope discrimination(13Δ)in C_(3)and C_(4)functional groups is critical for predicting C_(3)/C_(4)vegetation ratio from the isotopic composition of soil organic matter.In this study,we aimed to evaluate how intraspecific variation will modify functional group-level 13Δvalues and the associated prediction of C_(3)/C_(4)vegetation ratio.Methods We investigated 13Δof 726 individual plants(96 species;C_(3)and C_(4)functional groups)and topsoil organic matter in 26 grassland communities along an aridity gradient in northern China.The fraction of C_(4)contribution was calculated with mixing models that considered:(i)both intra-and interspecific effects on the 13Δvalues of C_(3)and C_(4)functional groups;(ii)only interspecific effects;or(iii)none of these effects.Important Findings We found divergent responses of plant 13Δat the intraspecific level to the changes of aridity across the gradient.The 13Δof both C_(3)and C_(4)functional groups was negatively correlated with an aridity index,with higher sensitivity for C_(3)than for C_(4)functional groups.Intraspecific 13Δvariation played a key role in driving the total 13Δvariations of C_(3)plants.Overlooking such intraspecific effect in mixing models led to a greatly increased fraction of C_(4)contribution to soil organic carbon.A correction for the effects of intraspecific variation is therefore essential for correctly inferring C_(3)/C_(4)vegetation ratio in the past.Our findings provide basic information for the reconstruction of past vegetation change from bulk materials in arid and semiarid biomes.
基金The work was supported by the National Natural Science Foundation of China(31770504,32171870)the Special Funds for Fundamental Research in Central Public Research Institutes(CAFYBB2019MA004)+1 种基金the Sino-German(CSC-DAAD)Postdoc Scholarship Program(57165010,2015)the German Research Foundation(DFG)(DynNiche,SCHU 2259/5-1 and SCHU 2259/5-2).
文摘Understanding how diaspore(hereafter‘seed’)morphology and orientation affect secondary seed dispersal by wind is important to link seed dispersal and post-dispersal processes,such as seed lodging,predation and germination.This study aims to describe the effects of seed morphology and orientation on secondary seed dispersal by wind via mechanistic modelling.We extend the mechanistic model of Schurr et al.(2005)in order to describe how secondary seed dispersal by wind is affected by wind conditions,ground surface,seed morphology and orientation.The model simulates the initial landing orientations,dispersal distances and stopping orientations of individual seeds.To parameterize the model,we measured orientation-specific vertical seed projection and seed lift-off velocity(the wind speed at which a seed starts moving on the ground)of the asymmetric seeds of heterocarpous Zygophyllum xanthoxylon,and determined orientation-specific model parameters that depend on properties of seeds and/or the environment.To validate the model,we conducted wind channel experiments in which we released seeds of Z.xanthoxylon onto a sand-coated tar paper,and recorded the initial landing orientations,dispersal distances and stopping orientations of the seeds.The extended model could precisely predict secondary dispersal distance,and explain up to 99%of variation in the observed proportions of seeds which stopped in various orientations.The model predicts that secondary dispersal distance increases with wind speed and decreases with aerodynamic roughness length,and that there might be a positive correlation between dispersal distance and germination success.