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1.
Medicine (Baltimore) ; 99(7): e19015, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32049797

RESUMO

Non-Hodgkin lymphoma (NHL) can co-exist with autoimmune hemolytic anemia (AIHA), a phenomenon known as AIHA-associated NHL (AIHA/NHL). However, few studies have reported AIHA/NHL incidence or its clinical characteristics. We conducted a retrospective analysis of 20 AIHA/NHL patients treated at our hospital from 2009 to 2018. AIHA/NHL was presented by only 0.91% of the NHL and 9.8% of the AIHA patients. In addition, AIHA occurred most frequently with angioimmunoblastic T-cell lymphoma (AITL) (7.31%), followed by marginal zone B-cell lymphoma (MZBL) (6.25%), B-cell lymphoma-unclassified (BCL-U) (4.25%), chronic lymphocytic leukemia/small lymphocyte lymphoma (CLL/SLL) (2.50%), and mantle cell lymphoma (MCL) (2.30%). In addition to the CLL/SLL patients with impaired bone marrow, 66.7% of the AIHA/NHL patients had lymphoma bone marrow infiltration (LBMI), of which 4 patients presented LBMI in bone marrow smears (BMS) but not in bone marrow biopsy (BMB) and 6 were positive for BMB but not BMS. The 1-, 3- and 5-year survival rates of AIHA/NHL patients were 70%, 30% and 20%, respectively, and they responded poorly to chemotherapy. In conclusion, AIHA can co-exist with various NHLs and the defining clinical characteristic of AIHA/NHL is the high incidence of LBMI. However, both BMS and BMB should be performed to avoid missed diagnosis.


Assuntos
Anemia Hemolítica Autoimune/epidemiologia , Medula Óssea/patologia , Linfoma não Hodgkin/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia Hemolítica Autoimune/patologia , Biópsia , Feminino , Humanos , Incidência , Linfoma não Hodgkin/classificação , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida
2.
Sci Total Environ ; 703: 135475, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31767296

RESUMO

Ectomycorrhizal (ECM) fungi are closely related to vegetation compositions, edaphic properties, and site-specific processes. However, the coevolutionary mechanisms underlying the spatial distributions in floristic and ECM fungal composition in the context of biotic adaptations and abiotic variances remain unclear. We combine a total of 25 ECM fungus-associated environmental variables to impose three types of composite scores and then quantify the environmental gradients of geographical site, soil chemical property and vegetation functional trait across 122 grids of 20 m × 20 m in a 25-hm2 forest plot. Significant dissimilarities in vegetational and ECM fungal abundance and composition existed along the above environmental gradients. Specifically, a contrasting floristic distribution (e.g., Betula platyphylla vs. Tilia mandshurica) existed between the northeastern and southwestern areas and was closely related to the nutrient and moisture gradients (with high levels in the west and low levels in the east). Furthermore, the ECM fungal communities were more abundant in the nutrient-poor and low-moisture environments than in the nutrient-rich and high-moisture environments, and the mixed-forest in the middle-gradient sites between the northeastern and southwestern areas harbored the highest ECM fungal diversity. These findings suggest that predictable within-site vegetation succession is closely related to ECM-associated determinants and the natural spatial heterogeneity of edaphic properties at a local scale.

3.
Zhongguo Zhong Yao Za Zhi ; 44(22): 4830-4836, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31872589

RESUMO

GRAS transcription factors play important roles in the regulation of plant root growth and GA signaling. In this study,SmGRAS3 gene was cloned,which open reading frame was 2 247 bp,and encoding 748 amino acids. The physicochemical properties and structure of SmGRAS3 and its encoded protein were analyzed by bioinformatics software. This gene belongs to the SCL9 subfamily of the GRAS family,and its promoter sequence mainly contains the light response,stress response,and hormone response elements. It may interact with the GA signal pathway and anti-stress related proteins. The subcellular localization showed that SmGRAS3 protein was mainly located in the nucleus. The expression pattern analysis showed that the expression of Sm GRAS3 was the highest in the root and the lowest in the stem,and both light and low temperature could induce the high expression level of SmGRAS3. This study provides a foundation for further study on the roles of SmGRAS3 gene in the root growth and stress tolerance of Salvia miltiorrhiza.


Assuntos
Salvia miltiorrhiza/genética , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas , Fatores de Transcrição
4.
BMC Genomics ; 20(1): 877, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31747870

RESUMO

BACKGROUND: Cadmium (Cd) is a serious heavy metal (HM) soil pollutant. To alleviate or even eliminate HM pollution in soil, environmental-friendly methods are applied. One is that special plants are cultivated to absorb the HM in the contaminated soil. As an excellent economical plant with ornamental value and sound adaptability, V. bonariensis could be adapted to this very situation. In our study, the Cd tolerance in V. bonariensis was analyzed as well as an overall analysis of transcriptome. RESULTS: In this study, the tolerance of V. bonariensis to Cd stress was investigated in four aspects: germination, development, physiological changes, and molecular alterations. The results showed that as a non-hyperaccumulator, V. bonariensis did possess the Cd tolerance and the capability to concentration Cd. Under Cd stress, all 237, 866 transcripts and 191, 370 unigenes were constructed in the transcriptome data of V. bonariensis roots. The enrichment analysis of gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway revealed that differentially expressed genes (DEGs) under Cd stress were predominately related to cell structure, reactive oxygen species (ROS) scavenging system, chelating reaction and secondary metabolites, transpiration and photosynthesis. DEGs encoding lignin synthesis, chalcone synthase (CHS) and anthocyanidin synthase (ANS) were prominent in V. bonariensis under Cd stress. The expression patterns of 10 DEGs, validated by quantitative real-time polymerase chain reaction (qRT-PCR), were in highly accordance with the RNA-Sequence (RNA-Seq) results. The novel strategies brought by our study was not only benefit for further studies on the tolerance of Cd and functional genomics in V. bonariensis, but also for the improvement molecular breeding and phytoremediation.

5.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(9): 898-903, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31506150

RESUMO

OBJECTIVE: To study the predictive value of Pediatric Age-adapted Sequential Organ Failure Assessment Score (pSOFA), Pediatric Risk of Mortality Score III (PRISM III), and Pediatric Critical Illness Score (PCIS) in children with severe sepsis. METHODS: A retrospective analysis was performed for the clinical data of 193 hospitalized children with severe sepsis. According to the final outcome, these children were divided into a survival group with 151 children and a death group with 42 children. The scores of pSOFA, PRISM III, and PCIS were determined according to the worst values of each index within 24 hours after admission. The receiver operating characteristic (ROC) curve was used to analyze the efficiency of each scoring system in predicting the risk of death due to sepsis. Smooth curve fitting was used to analyze the correlation between the three scoring systems and the threshold effect of each scoring system. Decision curve analysis (DCA) was used to evaluate the application value of each scoring system. RESULTS: The ROC analysis showed that PCIS and pSOFA had a similar predictive value (P=0.182) and that PRISM III and pSOFA had a similar predictive value (P=0.210), while PRISM III had a better predictive value than PCIS (P=0.045). PRISM III had the highest degree of fitting with prognosis, followed by pSOFA and PCIS. The DCA analysis showed that when the risk of death was 0.4 and 0.6 in children with severe sepsis and the three scoring systems were used as the basis for emergency intervention decision-making, pSOFA achieved the highest standardized net benefit, followed by PRISM III and PCIS. CONCLUSIONS: All three scoring systems have a certain value in predicting the prognosis of children with severe sepsis, and pSOFA has a better value than PRISM III and PCIS.


Assuntos
Escores de Disfunção Orgânica , Sepse , Criança , Estado Terminal , Humanos , Prognóstico , Curva ROC , Estudos Retrospectivos
6.
Math Biosci Eng ; 16(4): 2293-2304, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31137213

RESUMO

The growth of the species population is greatly influenced by seasonally varying environments. By regarding the maturation age of the species as a periodic developmental process, we propose a time periodic and diffusive model in bounded domain. To analyze this model with periodic delay, we first define the basic reproduction ratio R0 of the spatially homogeneous model and then show that the species population will be extinct when R0≤1 while remains persistent and tends to periodic oscillation if R0>1. Finally, combining the comparison principle with the fact that solutions of the spatially homogeneous model are also solutions of our model subject to Neumann boundary condition, we establish the global dynamics of a threshold type for PDE model in terms of R0.


Assuntos
Número Básico de Reprodução , Estações do Ano , Especificidade da Espécie , Algoritmos , Simulação por Computador , Modelos Biológicos , Dinâmica Populacional , Chuva
7.
BMC Genomics ; 19(1): 319, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29720105

RESUMO

BACKGROUND: Chrysanthemum is one kind of ornamental plant well-known and widely used in the world. However, its quality and production were severely affected by low temperature conditions in winter and early spring periods. Therefore, we used the RNA-Seq platform to perform a de novo transcriptome assembly to analyze chrysanthemum (Dendranthema grandiflorum) transcription response to low temperature. RESULTS: Using Illumina sequencing technology, a total of 86,444,237 high-quality clean reads and 93,837 unigenes were generated from four libraries: T01, controls; T02, 4 °C cold acclimation (CA) for 24 h; T03, - 4 °C freezing treatments for 4 h with prior CA; and T04, - 4 °C freezing treatments for 4 h without prior CA. In total, 7583 differentially expressed genes (DEGs) of 36,462 annotated unigenes were identified. We performed GO and KEGG pathway enrichment analyses, and excavated a group of important cold-responsive genes related to low temperature sensing and signal transduction, membrane lipid stability, reactive oxygen species (ROS) scavenging and osmoregulation. These genes encode many key proteins in plant biological processes, such as protein kinases, transcription factors, fatty acid desaturase, lipid-transfer proteins, antifreeze proteins, antioxidase and soluble sugars synthetases. We also verified expression levels of 10 DEGs using quantitative real-time polymerase chain reaction (qRT-PCR). In addition, we performed the determination of physiological indicators of chrysanthemum treated at low temperature, and the results were basically consistent with molecular sequencing results. CONCLUSION: In summary, our study presents a genome-wide transcript profile of Dendranthema grandiflorum var. jinba and provides insights into the molecular mechanisms of D. grandiflorum in response to low temperature. These data contributes to our deeper relevant researches on cold tolerance and further exploring new candidate genes for chilling-tolerance and freezing-tolerance chrysanthemum molecular breeding.


Assuntos
Chrysanthemum/genética , Chrysanthemum/fisiologia , Resposta ao Choque Frio/genética , Perfilação da Expressão Gênica , Aclimatação/genética , Membrana Celular/metabolismo , Chrysanthemum/citologia , Chrysanthemum/metabolismo , Anotação de Sequência Molecular , Osmose , Fenótipo , Reguladores de Crescimento de Planta/metabolismo , Proteínas Quinases/metabolismo , Análise de Sequência , Transdução de Sinais/genética , Fatores de Transcrição/metabolismo
8.
Environ Sci Pollut Res Int ; 25(15): 14614-14625, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29532374

RESUMO

A dual-permeability hydro-biodegradation model is developed to describe the leachate flow in municipal solid waste (MSW) and predict the long-term settlement induced by biodegradation in bioreactor landfills. The model is verified against Hydrus-1D and a recirculation experiment conducted in a full-scale landfill. Preferential flow and mass transfer between fissure and matrix can be reasonably modeled by the proposed model. A higher recirculation flow rate can speed up the stabilization process of landfill. However, too much recirculation leachate is not economical and environmental friendly. A stabilization speed index and a leachate utilization index are adopted to evaluate the stabilization speed of bioreactor landfill and utilization rate of leachate, respectively, and the optimal recirculation flow rate is estimated. A flow rate of q = 5 × 10-5-5 × 10-4 m/h (equivalent to recirculation intensity of Q = 15-150 L/tonwaste/year) is recommended for recirculation, which has been verified by the field data in numerous bioreactor landfills.


Assuntos
Reatores Biológicos , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/química , Biodegradação Ambiental , Modelos Teóricos , Permeabilidade , Eliminação de Resíduos , Resíduos Sólidos/análise
9.
Sci Rep ; 7(1): 13758, 2017 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-29062128

RESUMO

White- and brown-rot fungal decay via distinct pathways imparts characteristic molecular imprints on decomposing wood. However, the effect that a specific wood-rotting type of fungus has on proximal soil organic matter (SOM) accumulation remains unexplored. We investigated the potential influence of white- and brown-rot fungi-decayed Abies nephrolepis logs on forest SOM stocks (i.e., soil total carbon (C) and nitrogen (N)) and the concentrations of amino sugars (microbial necromass) at different depths and horizontal distances from decaying woody debris. The brown-rot fungal wood decay resulted in higher concentrations of soil C and N and a greater increase in microbial necromass (i.e., 1.3- to 1.7-fold greater) than the white-rot fungal wood decay. The white-rot sets were accompanied by significant differences in the proportions of the bacterial residue index (muramic acid%) with soil depth; however, the brown-rot-associated soils showed complementary shifts, primarily in fungal necromass, across horizontal distances. Soil C and N concentrations were significantly correlated with fungal rather than bacterial necromass in the brown-rot systems. Our findings confirmed that the brown-rot fungi-dominated degradation of lignocellulosic residues resulted in a greater SOM buildup than the white-rot fungi-dominated degradation.


Assuntos
Basidiomycota/classificação , Basidiomycota/metabolismo , Carbono/metabolismo , Nitrogênio/metabolismo , Compostos Orgânicos/metabolismo , Solo/química , Madeira/química
10.
Appl Opt ; 56(15): 4347-4352, 2017 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-29047859

RESUMO

The movement flatness error is one of the critical parameters of motorized stage performance. In this work, the measurement of the movement flatness error based on an astigmatic method is proposed, in which the focus error signal is detected and used to analyze the movement flatness error. The theoretical derivation and analysis are presented, and the experimental system is established accordingly. The experimental results indicate that our measurement method and established system exhibit an accuracy of less than ±100 nm. The movement flatness error of an x-y stepping motorized stage is measured using the established system, and the movement flatness error profile is mapped; it is determined that the maximum movement flatness error is within 1.3 µm in our experiment. The proposed method is hence proven to be an effective way of measuring the movement flatness error of motorized stages.

11.
Front Plant Sci ; 8: 1592, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28959270

RESUMO

High salinity seriously affects the production of chrysanthemum, so improving the salt tolerance of chrysanthemum becomes the focus and purpose of our research. The WRKY transcription factor (TF) family is highly associated with a number of processes of abiotic stress responses. We isolated DgWRKY4 from Dendranthema grandiflorum, and a protein encoded by this new gene contains two highly conserved WRKY domains and two C2H2 zinc-finger motifs. Then, we functionally characterized that DgWRKY4 was induced by salt, and DgWRKY4 overexpression in chrysanthemum resulted in increased tolerance to high salt stress compared to wild-type (WT). Under salt stress, the transgenic chrysanthemum accumulated less malondialdehyde, hydrogen peroxide (H2O2), and superoxide anion ([Formula: see text]) than WT, accompanied by more proline, soluble sugar, and activities of antioxidant enzymes than WT; in addition, a stronger photosynthetic capacity and a series of up-regulated stress-related genes were also found in transgenic chrysanthemum. All results demonstrated that DgWRKY4 is a positive regulatory gene responding to salt stress, via advancing photosynthetic capacity, promoting the operation of reactive oxygen species-scavenging system, maintaining membrane stability, enhancing the osmotic adjustment, and up-regulating transcript levels of stress-related genes. So, DgWRKY4 can serve as a new candidate gene for salt-tolerant plant breeding.

12.
Environ Sci Pollut Res Int ; 24(25): 20811-20817, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28791528

RESUMO

Leachate is a polluting liquid which may cause harmful effects on human health or the environment without a tightly control manner. The leachate management is an important part of the design and operation of bioreactor landfills. To detect the leachate distribution in Laogang Landfill, China, the measurement of electrical resistivity tomography (ERT) was carried out in three areas with different ages. ERT method proved to be an effective non-invasive geophysical method in bioreactor landfills, and the physical properties of waste samples obtained by boreholes were tested in a laboratory. The correlation between the resistivity and the moisture content was described by Archie's law. The result shows that the moisture content of fresh waste is inhomogeneous, while that of aged waste increases with depth. A pseudo 3D model of the moisture content was proposed to improve the understanding of leachate distribution and exhibit the accuracy of the ERT method.


Assuntos
Monitoramento Ambiental/métodos , Poluentes do Solo/análise , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/análise , Reatores Biológicos , China , Impedância Elétrica , Monitoramento Ambiental/instrumentação , Eliminação de Resíduos , Tomografia/métodos
13.
High Alt Med Biol ; 18(3): 219-225, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28846033

RESUMO

Cao, Xue-Feng, Zhen-Zhong Bai, Lan Ma, Shuang Ma, and Ri-Li Ge. Metabolic alterations of Qinghai-Tibet plateau pikas in adaptation to high altitude. High Alt Med Biol. 18:219-225, 2017.-To determine specific metabolic alterations in the myocardium of plateau pikas (Ochotona curzoniae) and potential metabolic biomarkers involved in their adaptation to the high-altitude environment of the Qinghai-Tibet Plateau. Ten pikas were captured by traps in the Kekexili Reserve (4630 m a.s.l; n = 5) and at the foot of the Laji Mountain (2600 m a.s.l; n = 5) on the Qinghai-Tibet Plateau, Qinghai Province, China. Metabolite levels were determined by gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) metabolomics, and multivariate statistical analysis was performed. Several metabolites involved in carbohydrate, fat, energy, and redox homeostasis pathways were significantly altered in pikas living at 4630 m. In addition, those pikas showed increased levels of lactic acid, sarcosine, 4-hydroxybutyrate, methionine, tartaric acid, ribose, tyrosine, pentadecanoic acid, 2-monoolein, 3,5-dihydroxyphenylglycine, trehalose-6-phosphate, succinic acid, myoinositol, fumaric acid, taurine, 2-hydroxybutanoic acid, gluconic acid, citrulline, and glutathione, but decreased levels of oleic acid and 2'-deoxyadenosine 5'-monophosphate. Metabolic activity is significantly altered in the myocardium of pikas in the high-altitude areas of the Qinghai-Tibet Plateau. This study provides important insights into metabolic biomarkers related to the adaptation of pikas to high-altitude hypoxia.


Assuntos
Aclimatação/fisiologia , Altitude , Lagomorpha/metabolismo , Metaboloma/fisiologia , Miocárdio/metabolismo , Animais , China , Análise Multivariada , Tibet
14.
Sci Rep ; 7(1): 4799, 2017 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-28684847

RESUMO

WRKY transcription factors play important roles in plant growth development, resistance and substance metabolism regulation. However, the exact function of the response to salt stress in plants with specific WRKY transcription factors remains unclear. In this research, we isolated a new WRKY transcription factor DgWRKY5 from chrysanthemum. DgWRKY5 contains two WRKY domains of WKKYGQK and two C2H2 zinc fingers. The expression of DgWRKY5 in chrysanthemum was up-regulated under various treatments. Meanwhile, we observed higher expression levels in the leaves contrasted with other tissues. Under salt stress, the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) enzymes in transgenic chrysanthemum were significantly higher than those in WT, whereas the accumulation of H2O2, O2- and malondialdehyde (MDA) was reduced in transgenic chrysanthemum. Several parameters including root length, root length, fresh weight, chlorophyll content and leaf gas exchange parameters in transgenic chrysanthemum were much better compared with WT under salt stress. Moreover, the expression of stress-related genes DgAPX, DgCAT, DgNCED3A, DgNCED3B, DgCuZnSOD, DgP5CS, DgCSD1 and DgCSD2 was up-regulated in DgWRKY5 transgenic chrysanthemum compared with that in WT. These results suggested that DgWRKY5 could function as a positive regulator of salt stress in chrysanthemum.


Assuntos
Chrysanthemum/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Estresse Salino/genética , Tolerância ao Sal/genética , Fatores de Transcrição/genética , Dedos de Zinco CYS2-HIS2 , Catalase/genética , Catalase/metabolismo , Chrysanthemum/efeitos dos fármacos , Chrysanthemum/metabolismo , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Peroxidase/genética , Peroxidase/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Caules de Planta/efeitos dos fármacos , Caules de Planta/genética , Caules de Planta/metabolismo , Plantas Geneticamente Modificadas , Domínios Proteicos , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/metabolismo , Cloreto de Sódio/farmacologia , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo , Fatores de Transcrição/metabolismo
15.
FEMS Microbiol Ecol ; 93(5)2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28499007

RESUMO

Understanding soil CO2 flux temperature sensitivity (Q10) is critical for predicting ecosystem-level responses to climate change. Yet, the effects of warming on microbial CO2 respiration still remain poorly understood under current Earth system models, partly as a result of thermal acclimation of organic matter decomposition. We conducted a 117-day incubation experiment under constant and diurnally varying temperature treatments based on four forest soils varying in vegetation stand and soil horizon. Our results showed that Q10 was greater under varying than constant temperature regimes. This distinction was most likely attributed to differences in the depletion of available carbon between constant high and varying high-temperature treatments, resulting in significantly higher rates of heterotrophic respiration in the varying high-temperature regime. Based on 16S rRNA gene sequencing data using Illumina, the varying high-temperature regime harbored higher prokaryotic alpha-diversity, was more dominated by the copiotrophic strategists and sustained a distinct community composition, in comparison to the constant-high treatment. We found a tightly coupled relationship between Q10 and microbial trophic guilds: the copiotrophic prokaryotes responded positively with high Q10 values, while the oligotrophs showed a negative response. Effects of vegetation stand and soil horizon consistently supported that the copiotrophic vs oligotrophic strategists determine the thermal sensitivity of CO2 flux. Our observations suggest that incorporating prokaryotic functional traits, such as shifts between copiotrophy and oligotrophy, is fundamental to our understanding of thermal acclimation of microbially mediated soil organic carbon cycling. Inclusion of microbial functional shifts may provide the potential to improve our projections of responses in microbial community and CO2 efflux to a changing environment in forest ecosystems.


Assuntos
Aclimatação/fisiologia , Bactérias/metabolismo , Dióxido de Carbono/metabolismo , Mudança Climática , Ecossistema , Florestas , Processos Heterotróficos , Temperatura Alta , RNA Ribossômico 16S/genética , Solo/química , Microbiologia do Solo
16.
Sci Total Environ ; 590-591: 242-248, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28262364

RESUMO

Soil respiration is the largest terrestrial carbon flux into the atmosphere, and different tree species could directly influence root derived respiration and indirectly regulate soil respiration rates by altering soil chemical and microbial properties. In this study, we assessed the small scale spatial heterogeneity of soil respiration and the microbial community below the canopy of three dominant tree species (Korean pine (Pinus koraiensis), Mongolian oak (Quercus mongolica), and Manchuria ash (Fraxinus mandshurica)) in a temperate mixed forest in Northeast China. Soil respiration differed significantly during several months and increased in the order of oak

Assuntos
Florestas , Microbiologia do Solo , Solo/química , Árvores/fisiologia , Carbono/análise , China , Fraxinus , Nitrogênio/análise , Pinus , Raízes de Plantas , Quercus
17.
Plant Cell Rep ; 36(4): 571-581, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28116501

RESUMO

KEY MESSAGE: DgNAC1, a transcription factor of chrysanthemum, was functionally verified to confer salt stress responses by regulating stress-responsive genes. NAC transcription factors play effective roles in resistance to different abiotic stresses, and overexpressions of NAC TFs in Arabidopsis have been proved to be conducive in improving salinity tolerance. However, functions of NAC genes in chrysanthemum continue to be poorly understood. Here, we performed physiology and molecular experiments to evaluate roles of DgNAC1 in chrysanthemum salt stress responses. In this study, DgNAC1-overexpressed chrysanthemum was obviously more resistant to salt over the WT (wild type). Specifically, the transgenic chrysanthemum showed a higher survival rate and lower EC (electrolyte conductivity) than WT under salt stress. The transgenic chrysanthemum also showed fewer accumulations of MDA (malondialdehyde) and reactive oxygen species (H2O2 and O2-), greater activities of SOD (superoxide dismutase), POD (peroxidase) and CAT (catalase), as well as more proline content than WT under salt stress. Furthermore, stress-responsive genes in transgenic chrysanthemum were greater up-regulated than in WT under salinity stress. Thus, all results revealed that DgNAC1 worked as a positive regulator in responses to salt stress and it may be an essential gene for molecular breeding of salt-tolerant plants.


Assuntos
Chrysanthemum/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Tolerância ao Sal/genética , Plantas Tolerantes a Sal/genética , Fatores de Transcrição/genética , Chrysanthemum/efeitos dos fármacos , Chrysanthemum/genética , Peróxido de Hidrogênio/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia , Salinidade , Plantas Tolerantes a Sal/efeitos dos fármacos , Plantas Tolerantes a Sal/metabolismo , Cloreto de Sódio/farmacologia , Fatores de Transcrição/metabolismo
18.
Sci Rep ; 7: 41700, 2017 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-28134322

RESUMO

Phormium tenax is a kind of drought resistant garden plant with its rich and colorful leaves. To clarify the molecular mechanism of drought resistance in Phormium tenax, transcriptome was sequenced by the Illumina sequencing technology under normal and drought stress, respectively. A large number of contigs, transcripts and unigenes were obtained. Among them, only 30,814 unigenes were annotated by comparing with the protein databases. A total of 4,380 genes were differentially expressed, 2,698 of which were finally annotated under drought stress. Differentially expression analysis was also performed upon drought treatment. In KEGG pathway, the mechanism of drought resistance in Phormium tenax was explained from three aspects of metabolism and signaling of hormones, osmotic adjustment and reactive oxygen species metabolism. These results are helpful to understand the drought tolerance mechanism of Phormium tenax and will provide a precious genetic resource for drought-resistant vegetation breeding and research.


Assuntos
Secas , Estresse Fisiológico , Transcriptoma , Xanthorrhoeaceae/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Xanthorrhoeaceae/fisiologia
19.
PLoS One ; 11(7): e0159721, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27447718

RESUMO

Salt stress has some remarkable influence on chrysanthemum growth and productivity. To understand the molecular mechanisms associated with salt stress and identify genes of potential importance in cultivated chrysanthemum, we carried out transcriptome sequencing of chrysanthemum. Two cDNA libraries were generated from the control and salt-treated samples (Sample_0510_control and Sample_0510_treat) of leaves. By using the Illumina Solexa RNA sequencing technology, 94 million high quality sequencing reads and 161,522 unigenes were generated and then we annotated unigenes through comparing these sequences to diverse protein databases. A total of 126,646 differentially expressed transcripts (DETs) were identified in leaf. Plant hormones, amino acid metabolism, photosynthesis and secondary metabolism were all changed under salt stress after the complete list of GO term and KEGG enrichment analysis. The hormone biosynthesis changing and oxidative hurt decreasing appeared to be significantly related to salt tolerance of chrysanthemum. Important protein kinases and major transcription factor families involved in abiotic stress were differentially expressed, such as MAPKs, CDPKs, MYB, WRKY, AP2 and HD-zip. In general, these results can help us to confirm the molecular regulation mechanism and also provide us a comprehensive resource of chrysanthemum under salt stress.


Assuntos
Chrysanthemum/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Folhas de Planta/genética , Tolerância ao Sal/genética , Estresse Fisiológico/genética , Transcriptoma , Chrysanthemum/efeitos dos fármacos , Chrysanthemum/metabolismo , Biologia Computacional/métodos , Bases de Dados Genéticas , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ontologia Genética , Genoma de Planta , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Salinidade , Transdução de Sinais/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos
20.
Sci Rep ; 6: 18783, 2016 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-26733344

RESUMO

Changes in soil organic carbon (SOC) stability may alter carbon release from the soil and, consequently, atmospheric CO2 concentration. The mean annual temperature (MAT) can change the soil physico-chemical characteristics and alter the quality and quantity of litter input into the soil that regulate SOC stability. However, the relationship between climate and SOC stability remains unclear. A 500-day incubation experiment was carried out on soils from an 11 °C-gradient mountainous system on Changbai Mountain in northeast China. Soil respiration during the incubation fitted well to a three-pool (labile, intermediate and stable) SOC decomposition model. A correlation analysis revealed that the MAT only influenced the labile carbon pool size and not the SOC stability. The intermediate carbon pool contributed dominantly to cumulative carbon release. The size of the intermediate pool was strongly related to the percentage of sand particle. The decomposition rate of the intermediate pool was negatively related to soil nitrogen availability. Because both soil texture and nitrogen availability are temperature independent, the stability of SOC was not associated with the MAT, but was heavily influenced by the intrinsic processes of SOC formation and the nutrient status.


Assuntos
Altitude , Carbono/química , Ecossistema , Florestas , Solo/química , China
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