Picea neoveitchii is an endemic species in China. It had been listed as an endangered species in red data books. It scatters in several locations of south slope of the Qinling Mountain of China. Upon reviewing the rel...Picea neoveitchii is an endemic species in China. It had been listed as an endangered species in red data books. It scatters in several locations of south slope of the Qinling Mountain of China. Upon reviewing the related literature, discussing with leading scholars on gymnosperm, ecology and plant conservation, the field survey was carried out in four locations. There are eleven mature individuals and two seedlings surviving in its natural habitats. With the survey of quadrat method in four locations, related community index were calculated such as relative important value (RIV), species richness, similarity index, diversity index and evenness index etc. The community could be sorted and characterized as three groups based on the community parameters. The analysis of vegetation table elucidates that Picea neoveitchii is a dominant species with low grouping rate in most surveyed sites. The RAPD analysis shows target species has intraspecific genetic variability. The estimation of Shannon’s phenotypic diversity index (Ho) also explains the difference of genetic variations of different locations. Due to the lack of enough knowledge and professional guide of conservation biological perspective, Picea neoveitchii had been clear-cut for timber production. The extent of occurrence and area of occupancy declined rapidly from 1950s to 1990s. According to the Conservation Category guideline proposed by the World Conservation Union, the conservation status of Picea neoveitchii was reevaluated as Critically Endangered (CR) B2b C2a D. Upon research in areas of ecology, molecular biology, cluster analysis of environmental parameters, a practical conservation strategy is recommended in this research.展开更多
Backgorund:Fruits and seed extracts of Annona montana have significant cytotoxic potential in several cancer cells.This study evaluates the effect of A.montana leaves hexane extract on several signaling cascades and g...Backgorund:Fruits and seed extracts of Annona montana have significant cytotoxic potential in several cancer cells.This study evaluates the effect of A.montana leaves hexane extract on several signaling cascades and gene expression in metastatic breast cancer cells upon insulin-like growth factor-1(IGF-1)stimulation.Methods:MTT assay was performed to determine the proliferation of cancer cells.Propidium iodide staining and flow cytometry analysis of Annexin V binding was utilized to measure the progression of the cell cycle and the induction of apoptosis.Protein expression and phosphorylation were determined by western blotting analysis to examine the underlying cellular mechanism triggered upon treatment with A.montana leaves hexane extract.Results:A.montana leaves hexane(subfraction V)blocked the constitutive stimulation of the PI3K/mTOR signaling pathways.This inhibitory effect was associated with apoptosis induction as evidenced by the positivity with Annexin V and terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNNEL)staining,activation of caspase-3,and cleavage of PPAR.It also limited the expression of various downstream genes that regulate proliferation,survival,metastasis,and angiogenesis(i.e.,cyclin D1,survivin,COX-2,and VEGF).It increased the expression of p53 and p21.Interestingly,we also observed that this extract blocked the activation of AKT and ERK without affecting the phosphorylation of the IGF-1 receptor and activation of Ras upon IGF-1 stimulation.Conclusion:Our study indicates that A.montana leaves(sub-fraction V)extract exhibits a selective anti-proliferative and proapoptotic effect on the metastatic MDA-MB-231 breast cancer cells through the involvement of PI3K/AKT/mTOR/S6K1 pathways.展开更多
The Annona genus is a member of Annonaceae,one of the largest families of plants across tropical and subtropical regions.This family has been used in several ethnomedicinal practices to treat a multitude of human dise...The Annona genus is a member of Annonaceae,one of the largest families of plants across tropical and subtropical regions.This family has been used in several ethnomedicinal practices to treat a multitude of human diseases.However,the molecular mechanism underlying its effect on the lipid droplet formation and on the expression of adipogenic markers of this plant remain to be investigated.In this study,we examined whether the extracts from the aerial part of Annona montana affect in vitro differentiation of preadipocytes.For our investigations,both mouse embryo fibroblast 3T3-L1 and normal human primary subcutaneous preadipocytes were incubated with Annona montana extracts(-and its subfractions-)and then analyzed on preadipocyte differentiation,lipid content,lipid droplet size and number,the expression of adipogenic-specific transcriptional factors,as well as cell survival.From our examinations,we found the Annona montana ethyl acetate extract to exhibit a potent inhibitory effect on adipogenesis,without affecting cell survival,in a dose-dependent manner.Such inhibitory effects included a significant decrease in the accumulation of lipid content by both a dramatic reduction of size and number of lipid droplets.This extract strongly attenuated the expression of PPARγand HMGB2.It also inhibited the expression of CEBPα,FAS,and Akt without influencing Erk1/2 activities.Our findings suggest that specifically,the Annona montana ethyl acetate extract has a prominent inhibitory effect in cellular pathways of adipocyte differentiation by modulating specific gene expression,which is known to perform a pivotal role during adipogenesis.展开更多
Background: The guild concept is useful for understanding the community structure in a land-bridge island system,but most fragmentation studies have focused only on the importance of island area and isolation, other i...Background: The guild concept is useful for understanding the community structure in a land-bridge island system,but most fragmentation studies have focused only on the importance of island area and isolation, other island attributes such as perimeter-area ratio(PAR) were overlooked or understudied.Methods: We have adopted a guild approach to investigate the impacts of island attributes on bird guild richness on a set of 41 recently isolated land-bridge islands in the Thousand Island Lake(TIL), China.Results: We found insectivores had the largest number of species(34 species), fol owed by understory foraging guilds(28 species), omnivores(27 species) and canopy guilds(25 species). Furthermore, our data showed that migrants and residents responded equal y to island area, insectivores and understory guilds were sensitive to island area but omnivores and canopy guilds were not very sensitive. Most guild richness was determined by island area, except for omnivores and canopy guilds.Conclusions: Although PAR or habitat diversity found to be important for bird species richness, our results highlight the importance of island area in maintaining bird diversity in fragmented island systems.展开更多
SiC BJT代表了最具吸引力的SiC开关结构之一,具有很低的电阻系数、较快的开关速度以及较小的温度依赖性。其良好的短路能力及不存在二次击穿可实现器件可靠工作。我们对与实际应用直接相关的器件性能进行了详细研究,并对以降耗为目的的...SiC BJT代表了最具吸引力的SiC开关结构之一,具有很低的电阻系数、较快的开关速度以及较小的温度依赖性。其良好的短路能力及不存在二次击穿可实现器件可靠工作。我们对与实际应用直接相关的器件性能进行了详细研究,并对以降耗为目的的驱动解决方案进行了测试。鉴于光伏系统降低成本的压力不断增加,我们额外进行了以实现节约为目的的实验,不仅基于SiC技术,同时包括新型磁芯材料方面。为此,我们在实验室中对一个额定功率为17kW的小型升压转换器进行了测试,并在本文中给出了结果。展开更多
Zephyranthes is valued as a native ornamental landscaping plant and a traditional medicinal herb. Due to the low seed viability, this study was carried out to evaluate the potential of seed embryo rescue using the art...Zephyranthes is valued as a native ornamental landscaping plant and a traditional medicinal herb. Due to the low seed viability, this study was carried out to evaluate the potential of seed embryo rescue using the artificial seed technique and long-preservation in Z. atamasca and Z. grandiflora. Seed embryos were selected for encapsulation with different concentration of sodium alginate (3%, 4%, and 5%) and calcium chloride (either 25, 50, 75, and 100 mM) followed by no encapsulated embryos as a control. The greatest viability of encapsulated embryos was 95% in Z. grandiflora and 85% in Z. atamasca with the combination of 4% sodium alginate and 100 mM calcium chloride after two weeks at 5°C. The highest viability with A<sub>490nm</sub>0.12 and A<sub>490nm</sub>0.16 were achieved when embryos were cultured in pretreatment medium with 30 g/L sucrose in Z. grandiflora and Z. atamasca, respectively. The highest viability by TTC assay after cryopreservation was observed with 54% viability for Z. grandiflora and 48% viability with Z. atamasca, after 2 h of dehydration. Rain lilies embryos were successfully preserved functioned as artificial seed and cryopreservation using encapsulation-dehydration method has been established for both species that can be used for other flower species with some modifications.展开更多
In-vitro propagation is a technique that provides a vital solution for the conservation of endangered orchid species. The media used in tissue culture can be modified through the addition of inexpensive organic materi...In-vitro propagation is a technique that provides a vital solution for the conservation of endangered orchid species. The media used in tissue culture can be modified through the addition of inexpensive organic materials as an alternative to expensive synthetic additives. Some organic sources, such as coconut water and fruit juice, contain significant amounts of vitamins, amino acids, and organic compounds which can act as growth regulators, making these organic sources excellent additives for in-vitro cultivation. The aim of this study was to develop a protocol for in-vitro micropropagation and acclimatization of Epidendrum nocturnum using organic supplements in the growth media and various substrates at the acclimatization stage. Banana powder, coconut water, and potato dextrose were added to a basal seed sowing media and evaluated for seed germination percentage and plantlet growth. In addition, various substrates such as coconut coir, horticultural charcoal, sphagnum moss, and wood bark were evaluated for height, number of leaves, and number of shoots in the acclimatization portion of this study. The culture medium with coconut water showed a greater germination percentage (71.00% and 76.75%) compared with the control (37.50% and 45.50%) at 60 and 90 days after seed sowing, respectively. Media with organic supplements showed greater values of plant length and number of roots compared with the control. The combination of coconut coir and horticultural charcoal was shown to be more efficient than the combination of sphagnum moss, horticultural charcoal, and wood bark, as results showed greater values of plant height and number of leaves at 30, 90, and 120 days after transplantation in acclimatization of E. nocturnum.展开更多
文摘Picea neoveitchii is an endemic species in China. It had been listed as an endangered species in red data books. It scatters in several locations of south slope of the Qinling Mountain of China. Upon reviewing the related literature, discussing with leading scholars on gymnosperm, ecology and plant conservation, the field survey was carried out in four locations. There are eleven mature individuals and two seedlings surviving in its natural habitats. With the survey of quadrat method in four locations, related community index were calculated such as relative important value (RIV), species richness, similarity index, diversity index and evenness index etc. The community could be sorted and characterized as three groups based on the community parameters. The analysis of vegetation table elucidates that Picea neoveitchii is a dominant species with low grouping rate in most surveyed sites. The RAPD analysis shows target species has intraspecific genetic variability. The estimation of Shannon’s phenotypic diversity index (Ho) also explains the difference of genetic variations of different locations. Due to the lack of enough knowledge and professional guide of conservation biological perspective, Picea neoveitchii had been clear-cut for timber production. The extent of occurrence and area of occupancy declined rapidly from 1950s to 1990s. According to the Conservation Category guideline proposed by the World Conservation Union, the conservation status of Picea neoveitchii was reevaluated as Critically Endangered (CR) B2b C2a D. Upon research in areas of ecology, molecular biology, cluster analysis of environmental parameters, a practical conservation strategy is recommended in this research.
基金supported by the National Institutes of Health Grant SC1DK084343(to MAB)by Mass Spectrometry Research and Education Center must cite funding from NIH S10 OD021758-01A1.
文摘Backgorund:Fruits and seed extracts of Annona montana have significant cytotoxic potential in several cancer cells.This study evaluates the effect of A.montana leaves hexane extract on several signaling cascades and gene expression in metastatic breast cancer cells upon insulin-like growth factor-1(IGF-1)stimulation.Methods:MTT assay was performed to determine the proliferation of cancer cells.Propidium iodide staining and flow cytometry analysis of Annexin V binding was utilized to measure the progression of the cell cycle and the induction of apoptosis.Protein expression and phosphorylation were determined by western blotting analysis to examine the underlying cellular mechanism triggered upon treatment with A.montana leaves hexane extract.Results:A.montana leaves hexane(subfraction V)blocked the constitutive stimulation of the PI3K/mTOR signaling pathways.This inhibitory effect was associated with apoptosis induction as evidenced by the positivity with Annexin V and terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNNEL)staining,activation of caspase-3,and cleavage of PPAR.It also limited the expression of various downstream genes that regulate proliferation,survival,metastasis,and angiogenesis(i.e.,cyclin D1,survivin,COX-2,and VEGF).It increased the expression of p53 and p21.Interestingly,we also observed that this extract blocked the activation of AKT and ERK without affecting the phosphorylation of the IGF-1 receptor and activation of Ras upon IGF-1 stimulation.Conclusion:Our study indicates that A.montana leaves(sub-fraction V)extract exhibits a selective anti-proliferative and proapoptotic effect on the metastatic MDA-MB-231 breast cancer cells through the involvement of PI3K/AKT/mTOR/S6K1 pathways.
基金supported by the National Institutes of Health Grant SC1DK084343the U.S.Department of Defense Grant W911NF-13-0167(to MAB).
文摘The Annona genus is a member of Annonaceae,one of the largest families of plants across tropical and subtropical regions.This family has been used in several ethnomedicinal practices to treat a multitude of human diseases.However,the molecular mechanism underlying its effect on the lipid droplet formation and on the expression of adipogenic markers of this plant remain to be investigated.In this study,we examined whether the extracts from the aerial part of Annona montana affect in vitro differentiation of preadipocytes.For our investigations,both mouse embryo fibroblast 3T3-L1 and normal human primary subcutaneous preadipocytes were incubated with Annona montana extracts(-and its subfractions-)and then analyzed on preadipocyte differentiation,lipid content,lipid droplet size and number,the expression of adipogenic-specific transcriptional factors,as well as cell survival.From our examinations,we found the Annona montana ethyl acetate extract to exhibit a potent inhibitory effect on adipogenesis,without affecting cell survival,in a dose-dependent manner.Such inhibitory effects included a significant decrease in the accumulation of lipid content by both a dramatic reduction of size and number of lipid droplets.This extract strongly attenuated the expression of PPARγand HMGB2.It also inhibited the expression of CEBPα,FAS,and Akt without influencing Erk1/2 activities.Our findings suggest that specifically,the Annona montana ethyl acetate extract has a prominent inhibitory effect in cellular pathways of adipocyte differentiation by modulating specific gene expression,which is known to perform a pivotal role during adipogenesis.
基金supported by the National Natural Science Foundation of China (No. 31170397)the Fundamental Research Funds for the Central Universities
文摘Background: The guild concept is useful for understanding the community structure in a land-bridge island system,but most fragmentation studies have focused only on the importance of island area and isolation, other island attributes such as perimeter-area ratio(PAR) were overlooked or understudied.Methods: We have adopted a guild approach to investigate the impacts of island attributes on bird guild richness on a set of 41 recently isolated land-bridge islands in the Thousand Island Lake(TIL), China.Results: We found insectivores had the largest number of species(34 species), fol owed by understory foraging guilds(28 species), omnivores(27 species) and canopy guilds(25 species). Furthermore, our data showed that migrants and residents responded equal y to island area, insectivores and understory guilds were sensitive to island area but omnivores and canopy guilds were not very sensitive. Most guild richness was determined by island area, except for omnivores and canopy guilds.Conclusions: Although PAR or habitat diversity found to be important for bird species richness, our results highlight the importance of island area in maintaining bird diversity in fragmented island systems.
文摘Zephyranthes is valued as a native ornamental landscaping plant and a traditional medicinal herb. Due to the low seed viability, this study was carried out to evaluate the potential of seed embryo rescue using the artificial seed technique and long-preservation in Z. atamasca and Z. grandiflora. Seed embryos were selected for encapsulation with different concentration of sodium alginate (3%, 4%, and 5%) and calcium chloride (either 25, 50, 75, and 100 mM) followed by no encapsulated embryos as a control. The greatest viability of encapsulated embryos was 95% in Z. grandiflora and 85% in Z. atamasca with the combination of 4% sodium alginate and 100 mM calcium chloride after two weeks at 5°C. The highest viability with A<sub>490nm</sub>0.12 and A<sub>490nm</sub>0.16 were achieved when embryos were cultured in pretreatment medium with 30 g/L sucrose in Z. grandiflora and Z. atamasca, respectively. The highest viability by TTC assay after cryopreservation was observed with 54% viability for Z. grandiflora and 48% viability with Z. atamasca, after 2 h of dehydration. Rain lilies embryos were successfully preserved functioned as artificial seed and cryopreservation using encapsulation-dehydration method has been established for both species that can be used for other flower species with some modifications.
文摘In-vitro propagation is a technique that provides a vital solution for the conservation of endangered orchid species. The media used in tissue culture can be modified through the addition of inexpensive organic materials as an alternative to expensive synthetic additives. Some organic sources, such as coconut water and fruit juice, contain significant amounts of vitamins, amino acids, and organic compounds which can act as growth regulators, making these organic sources excellent additives for in-vitro cultivation. The aim of this study was to develop a protocol for in-vitro micropropagation and acclimatization of Epidendrum nocturnum using organic supplements in the growth media and various substrates at the acclimatization stage. Banana powder, coconut water, and potato dextrose were added to a basal seed sowing media and evaluated for seed germination percentage and plantlet growth. In addition, various substrates such as coconut coir, horticultural charcoal, sphagnum moss, and wood bark were evaluated for height, number of leaves, and number of shoots in the acclimatization portion of this study. The culture medium with coconut water showed a greater germination percentage (71.00% and 76.75%) compared with the control (37.50% and 45.50%) at 60 and 90 days after seed sowing, respectively. Media with organic supplements showed greater values of plant length and number of roots compared with the control. The combination of coconut coir and horticultural charcoal was shown to be more efficient than the combination of sphagnum moss, horticultural charcoal, and wood bark, as results showed greater values of plant height and number of leaves at 30, 90, and 120 days after transplantation in acclimatization of E. nocturnum.
