In order to isolate meiotic chromosomes of Populus species meiotic chromosome preparation techniques of pollen mother cells for laser micro-dissection were studied. Pollen mother cells at diakinesis ofPopulus canadens...In order to isolate meiotic chromosomes of Populus species meiotic chromosome preparation techniques of pollen mother cells for laser micro-dissection were studied. Pollen mother cells at diakinesis ofPopulus canadensis Moench were used as samples. Two methods were used to prepare meiotic chromosomes： in the first, cell suspensions were dropped on polyethylene-naphthalate or polyester membrane slides which had just been incubated at -20~C; in the second method, cell suspensions were also dropped on polyethylene-naphthalate or polyester membrane slides, but spread with the aid of high temperatures. The cells did not completely spread by the first method and chromosomes at diakinesis could not be individually distinguished. In contrast, well-spread diakinesis chromosomes were obtained by the second method, where chromosomes, connected with their nucleolus, were successfully isolated with the laser micro-dissection system. As well, we discuss the prospect of applications of laser micro-dissection in cytogeneties and molecular genetics in Populus species.展开更多
Bud flushing is very important for the survival and growth of trees, a phenomenon matched each year with the annual course of temperature and the timing of bud flushing in the spring. Essentially it represents a serio...Bud flushing is very important for the survival and growth of trees, a phenomenon matched each year with the annual course of temperature and the timing of bud flushing in the spring. Essentially it represents a serious ecological and evolutionary tradeoff between survival and growth. The most suitable timing of bud burst permits trees to begin growth sufficiently early to take advantage of favorable spring conditions, but late enough to decrease the risks of tissue damage from late frost. In the present study bud burst spring phenology of poplar （Populus tremula and P. tremuloides） from eight different provenances, originating from Eu- rope and the USA, was observed during March and April, 2009. The experimental plot was located at Solling, Germany （51~44＇0＂ N, 9036＇0＇＇ E）. A six stage subjective scoring system of bud burst phenology was used to identify the phenological stages of the seed- lings, where each plant was observed twice a week. The aim of the study was to predict phenotypic variation in poplar, originating from regions between 42~ and 60~ N latitude, growing in similar environments. Timing of bud flushing of poplar was recorded. It was found that seedlings of provenance 3, which originated from 42.35~ N latitude, started and completed flushing significantly earlier than those of other provenances, while seedlings of provenance 5, originating from 54.29~ N latitude, started flushing very late and only a few plants reached top scoring at the end of the experimental period. Analysis of variance showed statistically highly signifi- cant differences （p 〈 0.05） in bud flushing among the provenances. The correlation between scoring and flushing periods was very strong within provenances although the flushing pattern differed among provenances （origin of the planted seedlings）. Bud flushing showed a negative correlation with the origin of the planted seedlings. Given the field experience gained with this experiment, it is recommended that seedlings from provenances 5 and 8 could be used for future plantations where late frost may be a problem for the young shoots of seedlings.展开更多
Recently,Prevotella spp.,a major genus of gram-negative commensal bacteria in humans,have emerged as a key microbial contributor to host metabolism due to its ability to ferment dietary fibers,produce beneficial short...Recently,Prevotella spp.,a major genus of gram-negative commensal bacteria in humans,have emerged as a key microbial contributor to host metabolism due to its ability to ferment dietary fibers,produce beneficial short-chain fatty acids,and influence immune responses.However,their diversity and functional differences have created challenges for their development and therapeutic use.Recent studies have shown that specific Prevotella species,such as P.copri,P.intestinalis,and P.histicola,can strengthen gut barrier integrity and reduce metabolic imbalances.Notably,Prevotella populations can be increased through high-fiber or herbal-based treatments.Traditional herbal medicines,including fiber-rich decoctions,also demonstrate the potential to boost endogenous Prevotella communities,enhance microbial fermentation,and improve glucose and lipid balance.This perspective examines the context-dependent roles of Prevotella spp.,with emphasis on the functional heterogeneity of key species such as P.copri,suggests a framework for combining herbal modulation with species-level microbiota profiling,and outlines a research plan to explore microbe-herb synergy in treating obesity,type 2 diabetes,and related metabolic disorders.This strategy offers a new,ecology-based approach to complement standard metabolic interventions.展开更多
理解新疆杨(Populus alba var.pyramidalis)耗水特征对制定沙地人工林科学用水灌溉策略以及林场经营建设具有重要意义。采用包裹式树干茎流仪测定新疆杨液流,并对毛乌素沙地的环境因子进行长期监测。结果表明:新疆杨晴天液流速率最大,...理解新疆杨(Populus alba var.pyramidalis)耗水特征对制定沙地人工林科学用水灌溉策略以及林场经营建设具有重要意义。采用包裹式树干茎流仪测定新疆杨液流,并对毛乌素沙地的环境因子进行长期监测。结果表明:新疆杨晴天液流速率最大,阴天次之,雨天最小,日液流累计量分别为16.38、12.56、2.22 L,晴天和阴天的液流速率接近。5、6、7、8、9、10月的日平均液流量分别为12.12、14.07、14.08、11.60、8.73、3.92 L,5—8月是新疆杨主要的耗水期,累计耗水量为1722.53 L。新疆杨液流与净辐射、饱和水汽压差、气温、太阳辐射、土壤热通量、土壤温度显著正相关,相关系数分别为0.656、0.641、0.634、0.625、0.605、0.467;与土壤湿度、空气相对湿度、降水量显著负相关,相关系数分别为-0.340、-0.233、-0.178;与风速相关性不显著。净辐射对于新疆杨液流的影响最大。展开更多
Tyrosine decarboxylase(TyDC)converts tyrosine to tyramine and plays a crucial role in secondary metabolite reactions,development,and stress responses in plants.Currently,the biological role of TyDC proteins from trees...Tyrosine decarboxylase(TyDC)converts tyrosine to tyramine and plays a crucial role in secondary metabolite reactions,development,and stress responses in plants.Currently,the biological role of TyDC proteins from trees is unknown.This study provided evidence showing that poplar PaTyDC4 functions in wood development and drought stress response.PaTyDC4 is preferentially expressed in wood-forming cells in stems.Overexpression of PaTyDC4 in poplars under the control of a xylem-specific promoter resulted in an increase in the ratio of xylem to phloem width,vessel cell area,and lignin accumulation in the stems.Biochemical assays revealed that PaTyDC4 was a component of the PaC3H17-PaMYB199 module-mediated pathway.In poplar stems,Pa TyDC4 expression was directly suppressed by PaMYB199,which was attenuated by the interaction between PaC3H17 and PaMYB199.In addition,Pa TyDC4 overexpression lines showed stronger drought tolerance than the wild-type lines,with higher photosynthetic capacity and lower levels of H_(2)O_(2).These results indicate that PaTyDC4 promotes xylem differentiation and lignin deposition during secondary growth and confers drought tolerance.Our findings may be useful for the genetic modification of biomass and drought resistance in trees.展开更多
Short rotation plantation forestry(SRF)is being widely adopted to increase wood production,in order to meet global demand for wood products.However,to ensure maximum gains from SRF,optimised management regimes need to...Short rotation plantation forestry(SRF)is being widely adopted to increase wood production,in order to meet global demand for wood products.However,to ensure maximum gains from SRF,optimised management regimes need to be established by integrating robust predictions and an understanding of mechanisms underlying tree growth.Hybrid ecophysiological models,such as potentially useable light sum equation(PULSE)models,are useful tools requiring minimal input data that meet the requirements of SRF.PULSE models have been tested and calibrated for different evergreen conifers and broadleaves at both juvenile and mature stages of tree growth with coarse soil and climate data.Therefore,it is prudent to question:can adding detailed soil and climatic data reduce errors in this type of model?In addition,PULSE techniques have not been used to model deciduous species,which are a challenge for ecophysiological models due to their phenology.This study developed a PULSE model for a clonal Populus tomentosa plantation in northern China using detailed edaphic and climatic data.The results showed high precision and low bias in height(m)and basal area(m^(2)·ha^(-1))predictions.While detailed edaphoclimatic data produce highly precise predictions and a good mechanistic understanding,the study suggested that local climatic data could also be employed.The study showed that PULSE modelling in combination with coarse level of edaphic and local climate data resulted in reasonably precise tree growth prediction and minimal bias.展开更多
Cronobacter spp.has strong resistance to desiccation and high permeability in Enterobacteriaceae,and powdered infant formula(PIF)is one of the main contamination routes.In recent years,the contamination of Cronobacter...Cronobacter spp.has strong resistance to desiccation and high permeability in Enterobacteriaceae,and powdered infant formula(PIF)is one of the main contamination routes.In recent years,the contamination of Cronobacter spp.in PIF incidents occurs from time to time,causing infant serious diseases or death.In this investigation,matrix-assisted laser desorption/ionization time of flight mass spectrometry was used to identify the phenotypes of 35 Cronobacter strains isolated from PIF and its processing environment.Subsequently,the isolates were evaluated for drying and osmotic pressure tolerance.The results showed that the deactivation rate of the strains ranged from 9.01%to 77.57%,and the highest osmotic pressure condition the strains could tolerate was 6 g/100 mL Na Cl.In addition,there was a positive correlation between biofilm formation ability and desiccation resistance.Combined with transcriptomics,Cronobacter spp.could activate biofilm synthesis,produce more trehalose,accumulate betaine and electrolytes to stabilize intracellular structure under the two treatment conditions.A total of 31 and 43 genes were found related to desiccation and permeability resistance,respectively.And some genes(cysM,thuF,ycjO,etc.)were found to be associated with two tolerances for the first time.展开更多
Objective:To evaluate the predictive value of secreted phosphoprotein 1(SPP1)gene expression for postoperative survival in patients with advanced liver cancer undergoing hepatic artery interventional chemoembolization...Objective:To evaluate the predictive value of secreted phosphoprotein 1(SPP1)gene expression for postoperative survival in patients with advanced liver cancer undergoing hepatic artery interventional chemoembolization treatment.Method:Bioinformatics methods,including gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis,were used to identify genes related to survival prognosis in hepatocellular carcinoma(HCC)patients.A retrospective analysis of 115 advanced liver cancer patients treated between January 2016 and October 2017 was conducted.Patients were categorized into SPP1 high-expression(n=89)and low-expression groups(n=26).Additionally,115 healthy individuals served as the control group.The relationship between SPP1 expression and clinical pathological features was analyzed.A 60-month follow-up and logistic regression analysis identified risk factors affecting survival.Results:SPP1 mRNA expression was significantly higher in liver cancer patients compared to healthy controls(P<0.05).SPP1 expression levels were significantly associated with tumor size,Child-Pugh grading,lymph node metastasis,and BCLC staging(P<0.05).High SPP1 expression,along with tumor size,Child-Pugh grading,lymph node metastasis,and BCLC staging,were independent risk factors for survival(P<0.05).The 60-month survival rate was 17.39%,with a median survival of 40 months in the low-expression group versus 18 months in the high-expression group(P<0.05).Conclusion:SPP1 expression is significantly upregulated in advanced liver cancer patients and has predictive value for postoperative survival following hepatic artery chemoembolization treatment.SPP1,combined with clinical indicators such as tumor size,Child-Pugh grading,lymph node metastasis,and BCLC staging,may serve as a prognostic biomarker for interventional treatment outcomes.展开更多
With the rapid development of nuclear energy,the removal of radioactive iodine generated during spent fuel reprocessing has become increasingly important.Based on the unique straw-like structure of populus tomentosa f...With the rapid development of nuclear energy,the removal of radioactive iodine generated during spent fuel reprocessing has become increasingly important.Based on the unique straw-like structure of populus tomentosa fiber(PTF)and the highly active iodine vapor capture ability of zero-valent silver nanoparticles(PTF@Ag^(0)NP),an Ag^(0)NP composite functional material with highly efficient iodine vapor capture capability was synthesized from biowaste PTF through ultrasonic and hightemperature hydrothermal methods in this study.The iodine capture experiment demonstrated that PTF@Ag^(0)NP exhibits rapid iodine capture efficiency,reaching dynamic equilibrium within 4 h and a maximum capture capacity of 1008.1 mg/g.Density functional theory calculations show that PTF@Ag^(0)NP exhibits extremely high chemical reactivity toward iodine,with a reaction binding energy of-2.88 e V.Additionally,the molecular dynamics of PTF@Ag^(0)NP indicate that there is no atomic displacement at 77?C,indicating the excellent temperature stability of the material at the operating temperature.The capture mechanism suggests that iodine vapor primarily reacts with Ag^(0)NP to form Ag I,and that the hydroxyl groups in PTF can also effectively capture iodine vapor by adsorption induction.In conclusion,PTF@Ag^(0)NP is expected to be an effective candidate adsorbent material for removing radioactive iodine vapor from exhaust gases during spent fuel reprocessing.展开更多
基金supported by the State Forestry Administration of China (2002-66)
文摘In order to isolate meiotic chromosomes of Populus species meiotic chromosome preparation techniques of pollen mother cells for laser micro-dissection were studied. Pollen mother cells at diakinesis ofPopulus canadensis Moench were used as samples. Two methods were used to prepare meiotic chromosomes： in the first, cell suspensions were dropped on polyethylene-naphthalate or polyester membrane slides which had just been incubated at -20~C; in the second method, cell suspensions were also dropped on polyethylene-naphthalate or polyester membrane slides, but spread with the aid of high temperatures. The cells did not completely spread by the first method and chromosomes at diakinesis could not be individually distinguished. In contrast, well-spread diakinesis chromosomes were obtained by the second method, where chromosomes, connected with their nucleolus, were successfully isolated with the laser micro-dissection system. As well, we discuss the prospect of applications of laser micro-dissection in cytogeneties and molecular genetics in Populus species.
基金supported by the Institute of Forest Genetics and Forest Tree Breedingthe Institute of Forest Botany, Georg-August-University, Gttingen,Germanyprovided by the university and a scholarship from the European Union
文摘Bud flushing is very important for the survival and growth of trees, a phenomenon matched each year with the annual course of temperature and the timing of bud flushing in the spring. Essentially it represents a serious ecological and evolutionary tradeoff between survival and growth. The most suitable timing of bud burst permits trees to begin growth sufficiently early to take advantage of favorable spring conditions, but late enough to decrease the risks of tissue damage from late frost. In the present study bud burst spring phenology of poplar （Populus tremula and P. tremuloides） from eight different provenances, originating from Eu- rope and the USA, was observed during March and April, 2009. The experimental plot was located at Solling, Germany （51~44＇0＂ N, 9036＇0＇＇ E）. A six stage subjective scoring system of bud burst phenology was used to identify the phenological stages of the seed- lings, where each plant was observed twice a week. The aim of the study was to predict phenotypic variation in poplar, originating from regions between 42~ and 60~ N latitude, growing in similar environments. Timing of bud flushing of poplar was recorded. It was found that seedlings of provenance 3, which originated from 42.35~ N latitude, started and completed flushing significantly earlier than those of other provenances, while seedlings of provenance 5, originating from 54.29~ N latitude, started flushing very late and only a few plants reached top scoring at the end of the experimental period. Analysis of variance showed statistically highly signifi- cant differences （p 〈 0.05） in bud flushing among the provenances. The correlation between scoring and flushing periods was very strong within provenances although the flushing pattern differed among provenances （origin of the planted seedlings）. Bud flushing showed a negative correlation with the origin of the planted seedlings. Given the field experience gained with this experiment, it is recommended that seedlings from provenances 5 and 8 could be used for future plantations where late frost may be a problem for the young shoots of seedlings.
基金supported by the National Research Foundation of Korea(2020R1F1A1074155).
文摘Recently,Prevotella spp.,a major genus of gram-negative commensal bacteria in humans,have emerged as a key microbial contributor to host metabolism due to its ability to ferment dietary fibers,produce beneficial short-chain fatty acids,and influence immune responses.However,their diversity and functional differences have created challenges for their development and therapeutic use.Recent studies have shown that specific Prevotella species,such as P.copri,P.intestinalis,and P.histicola,can strengthen gut barrier integrity and reduce metabolic imbalances.Notably,Prevotella populations can be increased through high-fiber or herbal-based treatments.Traditional herbal medicines,including fiber-rich decoctions,also demonstrate the potential to boost endogenous Prevotella communities,enhance microbial fermentation,and improve glucose and lipid balance.This perspective examines the context-dependent roles of Prevotella spp.,with emphasis on the functional heterogeneity of key species such as P.copri,suggests a framework for combining herbal modulation with species-level microbiota profiling,and outlines a research plan to explore microbe-herb synergy in treating obesity,type 2 diabetes,and related metabolic disorders.This strategy offers a new,ecology-based approach to complement standard metabolic interventions.
基金Financial support was obtained from National Natural Science Foundation of China(Grant Nos.32101549 and 32201585)Natural Science Foundation of Shandong Province,China(Grant No.ZR202112010288)+2 种基金Science&Technology Specific Projects in Agricultural High-tech Industrial Demonstration Area of the Yellow River Delta(Grant No.2022SZX39)Technical Innovation and Application Development Special Project of Chongqing(Grant No.CSTB2022TIAD-LDX0013)the Taishan Scholar Program of Shandong(Grant No.tsqn202103092)。
文摘Tyrosine decarboxylase(TyDC)converts tyrosine to tyramine and plays a crucial role in secondary metabolite reactions,development,and stress responses in plants.Currently,the biological role of TyDC proteins from trees is unknown.This study provided evidence showing that poplar PaTyDC4 functions in wood development and drought stress response.PaTyDC4 is preferentially expressed in wood-forming cells in stems.Overexpression of PaTyDC4 in poplars under the control of a xylem-specific promoter resulted in an increase in the ratio of xylem to phloem width,vessel cell area,and lignin accumulation in the stems.Biochemical assays revealed that PaTyDC4 was a component of the PaC3H17-PaMYB199 module-mediated pathway.In poplar stems,Pa TyDC4 expression was directly suppressed by PaMYB199,which was attenuated by the interaction between PaC3H17 and PaMYB199.In addition,Pa TyDC4 overexpression lines showed stronger drought tolerance than the wild-type lines,with higher photosynthetic capacity and lower levels of H_(2)O_(2).These results indicate that PaTyDC4 promotes xylem differentiation and lignin deposition during secondary growth and confers drought tolerance.Our findings may be useful for the genetic modification of biomass and drought resistance in trees.
基金The National Key Research and Development Program of China(Grant No.2021YFD2201203)the 5·5 Engineering Research&Innovation Team Project of Beijing Forestry University(No.BLRC2023C05)the Key Research and Development Program of Shandong Province(No.2021SFGC02050102)。
文摘Short rotation plantation forestry(SRF)is being widely adopted to increase wood production,in order to meet global demand for wood products.However,to ensure maximum gains from SRF,optimised management regimes need to be established by integrating robust predictions and an understanding of mechanisms underlying tree growth.Hybrid ecophysiological models,such as potentially useable light sum equation(PULSE)models,are useful tools requiring minimal input data that meet the requirements of SRF.PULSE models have been tested and calibrated for different evergreen conifers and broadleaves at both juvenile and mature stages of tree growth with coarse soil and climate data.Therefore,it is prudent to question:can adding detailed soil and climatic data reduce errors in this type of model?In addition,PULSE techniques have not been used to model deciduous species,which are a challenge for ecophysiological models due to their phenology.This study developed a PULSE model for a clonal Populus tomentosa plantation in northern China using detailed edaphic and climatic data.The results showed high precision and low bias in height(m)and basal area(m^(2)·ha^(-1))predictions.While detailed edaphoclimatic data produce highly precise predictions and a good mechanistic understanding,the study suggested that local climatic data could also be employed.The study showed that PULSE modelling in combination with coarse level of edaphic and local climate data resulted in reasonably precise tree growth prediction and minimal bias.
基金supported by the Joint Funds of the National Natural Science Foundation of China(U21A20272)。
文摘Cronobacter spp.has strong resistance to desiccation and high permeability in Enterobacteriaceae,and powdered infant formula(PIF)is one of the main contamination routes.In recent years,the contamination of Cronobacter spp.in PIF incidents occurs from time to time,causing infant serious diseases or death.In this investigation,matrix-assisted laser desorption/ionization time of flight mass spectrometry was used to identify the phenotypes of 35 Cronobacter strains isolated from PIF and its processing environment.Subsequently,the isolates were evaluated for drying and osmotic pressure tolerance.The results showed that the deactivation rate of the strains ranged from 9.01%to 77.57%,and the highest osmotic pressure condition the strains could tolerate was 6 g/100 mL Na Cl.In addition,there was a positive correlation between biofilm formation ability and desiccation resistance.Combined with transcriptomics,Cronobacter spp.could activate biofilm synthesis,produce more trehalose,accumulate betaine and electrolytes to stabilize intracellular structure under the two treatment conditions.A total of 31 and 43 genes were found related to desiccation and permeability resistance,respectively.And some genes(cysM,thuF,ycjO,etc.)were found to be associated with two tolerances for the first time.
基金Medical Research Project of Xi’an Science and Technology Bureau“Molecular Mechanism of miR-1305 Competitive Endogenous circRNA in the Development of Liver Cancer”(Project No.22YXYJ0134)General Project of Key Research and Development Program of Shaanxi Provincial Department of Science and Technology“Mechanism Study on the Inhibition of Liver Cancer Invasion and Metastasis by Downregulating METTL3 and Reducing the m6A Modification Level of MMP3 with Honokiol”(Project No.2023-YBSF-631)。
文摘Objective:To evaluate the predictive value of secreted phosphoprotein 1(SPP1)gene expression for postoperative survival in patients with advanced liver cancer undergoing hepatic artery interventional chemoembolization treatment.Method:Bioinformatics methods,including gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis,were used to identify genes related to survival prognosis in hepatocellular carcinoma(HCC)patients.A retrospective analysis of 115 advanced liver cancer patients treated between January 2016 and October 2017 was conducted.Patients were categorized into SPP1 high-expression(n=89)and low-expression groups(n=26).Additionally,115 healthy individuals served as the control group.The relationship between SPP1 expression and clinical pathological features was analyzed.A 60-month follow-up and logistic regression analysis identified risk factors affecting survival.Results:SPP1 mRNA expression was significantly higher in liver cancer patients compared to healthy controls(P<0.05).SPP1 expression levels were significantly associated with tumor size,Child-Pugh grading,lymph node metastasis,and BCLC staging(P<0.05).High SPP1 expression,along with tumor size,Child-Pugh grading,lymph node metastasis,and BCLC staging,were independent risk factors for survival(P<0.05).The 60-month survival rate was 17.39%,with a median survival of 40 months in the low-expression group versus 18 months in the high-expression group(P<0.05).Conclusion:SPP1 expression is significantly upregulated in advanced liver cancer patients and has predictive value for postoperative survival following hepatic artery chemoembolization treatment.SPP1,combined with clinical indicators such as tumor size,Child-Pugh grading,lymph node metastasis,and BCLC staging,may serve as a prognostic biomarker for interventional treatment outcomes.
基金supported by the Sichuan Outstanding Young Scientific and Technological Talents Project(No.2021JDJQ0016)Doctoral Initiation Project of China West Normal University(No.22k E043)and Science and Technology Project of Sichuan Province(No.2022NSFSC0388)。
文摘With the rapid development of nuclear energy,the removal of radioactive iodine generated during spent fuel reprocessing has become increasingly important.Based on the unique straw-like structure of populus tomentosa fiber(PTF)and the highly active iodine vapor capture ability of zero-valent silver nanoparticles(PTF@Ag^(0)NP),an Ag^(0)NP composite functional material with highly efficient iodine vapor capture capability was synthesized from biowaste PTF through ultrasonic and hightemperature hydrothermal methods in this study.The iodine capture experiment demonstrated that PTF@Ag^(0)NP exhibits rapid iodine capture efficiency,reaching dynamic equilibrium within 4 h and a maximum capture capacity of 1008.1 mg/g.Density functional theory calculations show that PTF@Ag^(0)NP exhibits extremely high chemical reactivity toward iodine,with a reaction binding energy of-2.88 e V.Additionally,the molecular dynamics of PTF@Ag^(0)NP indicate that there is no atomic displacement at 77?C,indicating the excellent temperature stability of the material at the operating temperature.The capture mechanism suggests that iodine vapor primarily reacts with Ag^(0)NP to form Ag I,and that the hydroxyl groups in PTF can also effectively capture iodine vapor by adsorption induction.In conclusion,PTF@Ag^(0)NP is expected to be an effective candidate adsorbent material for removing radioactive iodine vapor from exhaust gases during spent fuel reprocessing.
