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1.
Am J Bot ; 109(6): 910-921, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35471767

RESUMO

PREMISE: Exploring how functional traits vary and covary is important to understand plant responses to environmental change. However, we have limited understanding of the ways multiple functional traits vary and covary within invasive species. METHODS: We measured 12 leaf traits of an invasive plant Chromolaena odorata, associated with plant or leaf economics, herbivore defense, and drought resistance on 10 introduced populations from Asia and 12 native populations from South and Central America, selected across a broad range of climatic conditions, and grown in a common garden. RESULTS: Species' range and climatic conditions influenced leaf traits, but trait variation across climate space differed between the introduced and native ranges. Traits that confer defense against herbivores and drought resistance were associated with economic strategy, but the patterns differed by range. Plants from introduced populations that were at the fast-return end of the spectrum (high photosynthetic capacity) had high physical defense traits (high trichome density), whereas plants from native populations that were at the fast-return end of the spectrum had high drought escape traits (early leaf senescence and high percentage of withered shoots). CONCLUSIONS: Our results indicate that invasive plants can rapidly adapt to novel environmental conditions. Chromolaena odorata showed multiple different functional trait covariation patterns and clines in the native and introduced ranges. Our results emphasize that interaction between multiple traits or functions should be considered when investigating the adaptive evolution of invasive plants.


Assuntos
Secas , Herbivoria , Espécies Introduzidas , Folhas de Planta/fisiologia , Plantas
2.
Zhongguo Zhong Yao Za Zhi ; 46(18): 4704-4711, 2021 Sep.
Artigo em Zh | MEDLINE | ID: mdl-34581079

RESUMO

As the main chemical constituents, iridoids are widely distributed within Gentiana, Gentianaceae, with promising bioactivities. Based on the previous work, the transcriptome of G. lhassica, an original plant of Tibetan herb "Jieji Nabao", was sequenced and analyzed in this study, and the transcriptome databases of roots, stems, leaves, and flowers were constructed so as to explore unigenes that may encode the key enzymes in the biosynthetic pathway of iridoids. Then, qRT-PCR was used to validate the relative expression levels of 11 genes named AACT, DXS, MCS, HDS, IDI, GPPS, GES, G10H, 7-DLNGT, 7-DLGT, and SLS in roots, stems, leaves, and flowers. Also, the total contents of gentiopicroside and loganic acid were determined by HPLC, respectively. The results are as follows:(1)a total of 76 486 unigenes with an average length of 852 bp were obtained;(2)335 unigenes were involved in 19 stan-dard secondary metabolism pathways in KEGG database, with phenylpropanoid biosynthesis having the maximum number(75 unigenes), and no isoflavone biosynthetic pathway was annotated;(3)171 unigenes participatedin 27 key enzymes encoding in the biosynthetic pathway of iridoids, and 1-deoxy-D-xylulose-5-phosphate reductoisomerase(DXR) gene was highly expressed;(4)qRT-PCR results were approximately consistent with RNA-Seq data and the relative expression levels of the 11 genes were higher in the aboveground parts(stem, leaf, and flower) than in the underground part(root);(5)the total contents of gentiopicroside and loganic acid were higher in the aboveground parts(stem, leaf, and flower) than in the underground part(root), and the difference was significant. This study provides basic scientific data for accurate species identification, evaluation of germplasm resources, research on secondary pro-duct accumulation of medicinal plants within Gentianaceae, and protection of endangered alpine species.


Assuntos
Gentiana , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Gentiana/genética , Iridoides , Transcriptoma
3.
Mol Phylogenet Evol ; 107: 345-355, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27908741

RESUMO

Phylogenomics has shown great potential in resolving evolutionary relationships at different taxonomical levels. However, it remains controversial whether all orthologous genes under different selective pressures can be concatenated for phylogenomic reconstruction. Here we used sect. Cyathophora of Pedicularis, one of the most species-rich genera of angiosperms in the alpine and arctic regions of the Northern Hemisphere, as a model to investigate the efficiency of RNA-seq in resolving relationships of closely related congeneric species. Flower transcriptomes were sequenced for all species of sect. Cyathophora and two outgroup species. Forty-one highly conserved single-/low-copy nuclear genes and 1553 orthologous groups (OGs) were identified and concatenated into five datasets based on gene copy numbers and Ka/Ks values to reconstruct the phylogeny of section Cyathophora. We also tested how many genes minimally can resolve the interspecific relationships, and reconstructed the evolutionary history of some floral characters in sect. Cyathophora. The results showed that the five different datasets consistently resolved the interspecific relationships of sect. Cyathophora, and the interspecific relationships can be robustly reconstructed with maximal support when ⩾20 single-/low-copy nuclear genes or 25 OGs are used. Our study suggests that all OGs under different selective pressures can be concatenated for phylogenomic reconstruction, and provides a successful and efficient use of RNA-seq in reconstructing interspecific relationships of a non-model plant group with recent radiations.


Assuntos
Pedicularis/classificação , Pedicularis/genética , Filogenia , Análise de Sequência de RNA/métodos , Regiões Árticas , Sequência de Bases , Núcleo Celular/genética , Bases de Dados Genéticas , Flores/genética , Dosagem de Genes , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Genômica , Funções Verossimilhança , RNA de Plantas/genética , Especificidade da Espécie , Fatores de Tempo , Transcriptoma/genética
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(4): 972-7, 2016 Apr.
Artigo em Zh | MEDLINE | ID: mdl-30048092

RESUMO

Spine is one of the most important organs in the human body. One of the most commonly used method for the treatment of spinal diseases is the internal fixation and accurate placement of pedicle screw, which is a key factor of spinal surgery. However, due to the large differences as to the appearance of pedicles, it is hard to place the pedicle screw precisely, which will cause complication. Therefore, to find a new real-time intra-operative monitoring method with navigation is the direction of clinical application research. In this paper, a new method was firstly proposed. This method combined computer tomography (CT) values and near-infrared spectroscopy (NIRs) measurement data to guide the PS placement, and the relationship between NIRs parameters and CT values along the PS trajectory in vertebrae was investigated. First, we took pig vertebrae as samples and different puncture paths were planned. Second, a near-infrared monitoring device was utilized in experiments of fresh pig vertebrae to acquire the best NIRs monitoring pattern factors. Finally, the correlation function between NIRs data and CT values pattern factors was obtained. The results showed that CT values have a linear relationship with NIRs monitoring pattern factors, which provide references for real-time monitoring method in pedicle screw fixation surgery. This model can be applied in monitoring the pedicle screw implantation and alarming. The proposed method will be potential in improving the accuracy of PS placement and reduce the risk caused by the misplacement of pedicle screw.

5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(11): 3630-6, 2016 Nov.
Artigo em Zh | MEDLINE | ID: mdl-30199171

RESUMO

Leaf electrolyte leakage is an important index of the plant cell permeability which plays an important role in the study of turfgrass salt stress. Traditional methods of measuring leaf electrolyte leakage have many disadvantages such as time-consuming, destroying the plants and being unable to monitor salt stress in large area. The aim of this study is to build a hyperspectral inversion model for leaf electrolyte leakage of creeping bentgrass under different salt concentration stresses thus to promote the application of the hyperspectral techniques in turfgrass salt stress monitoring. Creeping bentgrass was used in this study, and it was grown in water for two weeks before salt treatments. Leaves were collected at 7, 14 and 21 d under 0(CK), 100 and 200 mmol·L-1 NaCl respectively. The spectral values were gathered using Unispec-SC Spectral Analysis System (PP SYSTEMS,USA)before collecting grass leaves. Leaf electrolyte leakage was measured with electrical conductivity method. The relation and differences between salt treatments and spectral reflectance values were analyzed with EXCEL. Normalized difference vegetation index (NDVI) and difference vegetation index (DVI) were calculated using the spectral reflectance values. The first-order differential was calculated with difference method. The trilateral parameters of the blue, green and red rays were calculated at the meantime. The correlation analysis of the Leaf electrolyte leakage, spectral reflectance value, DVI and trilateral parameters was achieved by using EXCEL and Matlab software. Electrolyte leakage inversion model of the calibration set consisted of 48 high correlational samples, was built using unary linear regression, multivariate linear regression and partial least-squares regression methods. The prediction set inspection inversion model was established using the other 24 samples. The results showed that there is a positive correlation between salt stresses and 450~700 nm wave band. The leaf electrolyte leakage was positively associated with 450~732 nm band region at 0.01. The green edge amplitude and area of green edge were correlated with the foliar electrolyte leakage positively. Models based on partial least squares regression could inversion the foliar electrolyte leakage optimally. The calibration R2 reached to 0.681, and the validation R2 reached to 0.758. The calibration RMSE was 7.124, and the validation RMSE reached to 7.079. The inversion model made it possible to detect creeping bentgrass leaf electrolyte leakage under salt stress rapidly. This study also provided theoretical reference for monitoring the damage of other creeping bentgrass related plant species resulted by salt stress.


Assuntos
Agrostis , Eletrólitos , Análise dos Mínimos Quadrados , Modelos Lineares , Folhas de Planta , Plantas , Análise Espectral , Água
6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(8): 2246-51, 2015 Aug.
Artigo em Zh | MEDLINE | ID: mdl-26672303

RESUMO

The physiological mechanism and ecological structure of forest trees can change with the changes of years. In a certain extent, the changes were expressed through the canopy spectral features. The mastery of changing rules about spectral characteristics of trees over the years is benefit to remote sensing interpretation and provide scientific basis for the classification of different trees. The study adopted high-resolution spectrometer to measure the canopy spectral characteristics for seven major deciduous trees and seven evergreen trees to gain the spectrum curve of four different ages and calculate the first derivative curve. The analysis of changing rules about spectral characteristics of different deciduous trees and evergreen trees and the comparison of changes about spectrum of various trees in the visible and infrared band could find the best year and best band for identification of trees. The results showed that the canopy spectral reflectance of deciduous and evergreen trees increases with the increase of age. And the spectral changes of two species were most obvious in the near infrared band.


Assuntos
Florestas , Folhas de Planta , Estações do Ano , China , Análise Espectral , Árvores/crescimento & desenvolvimento
7.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(8): 847-51, 2015 Aug.
Artigo em Zh | MEDLINE | ID: mdl-26287351

RESUMO

OBJECTIVE: To compare the differences of clinical efficacy between heated humidified high-flow nasal cannula (HHHFNC) ventilation and nasal continuous positive airway pressure (NCPAP) in the treatment of respiratory distress syndrome (RDS) in very low birth weight (VLBW) infants. METHODS: A total of 66 VLBW infants who were admitted to the neonatal intensive care unit were diagnosed with RDS, and they were randomly assigned to HHHFNC group and NCPAP group after receiving treatment with porcine pulmonary surfactant and conventional treatment. The changes in clinical symptoms and the incidence of complications were observed in the two groups. RESULTS: The HHHFN group had significantly earlier first milk feeding and full enteral feeding, significantly shorter oxygen exposure time and invasive ventilation time, and significantly lower incidences of second intubation within 7 days, nasal injury, air leak, and abdominal distention, as compared with the NCPAP group. CONCLUSIONS: Compared with NCPAP, HHHFNC causes slighter injury and has better tolerability, and it can be considered as the first choice of noninvasive ventilation in the treatment of RDS in VLBW infants.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas/métodos , Recém-Nascido de muito Baixo Peso , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Feminino , Humanos , Recém-Nascido , Masculino
8.
Talanta ; 278: 126546, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39002263

RESUMO

As a new type of porous crystalline composite material, MOF-COF has shown great advantages in metal separation. Herein, a CoMOF-COF was designed for highly selective separation of trace Pb2+ ions. The designed CoMOF-COF has a high density of nitrogen-oxygen functional groups and can selectively separate metal ions. There is a strong affinity between the designed CoMOF-COF material and metal Pb2+ ions, which can be attributed to the ordered heterogeneous porous structure and large amounts of nitrogen-and oxygen-containing functional groups. The composite showed high adsorption selectivity for Pb2+ ions and had adsorption capacity of 33 mg g-1, with high chemical stability. Based on this solid phase extraction material, a high sensitivity detection method for Pb2+ ions was established, which has the detection limit of 37.3 ng L-1, precision of 1.9 %. Linear detection range is 0.2-10 ng mL-1, and the detection of Pb2+ ions in actual water samples was realized. Through this study, it is proved that the strong affinity between the designed CoMOF-COF materials and metal Pb2+ ions can be attributed to the soft and hard acid-base theory, which reveals the structure-activity relationship between the porous heterostructure of such materials and metal separation, providing a highly selective separation material for the separation of other environmental pollutants.

9.
Huan Jing Ke Xue ; 43(1): 306-313, 2022 Jan 08.
Artigo em Zh | MEDLINE | ID: mdl-34989515

RESUMO

To explore the composition of the nirS denitrifying bacterial community during stratification in spring(March to May) in a drinking water reservoir and its relationship with water quality, the water quality and relative abundance and structure of the denitrifying bacterial community were analyzed using in-situ monitoring coupled with Illumina high-throughput sequencing technology in the Lijiahe Reservoir. The results showed that:① through high-throughput sequencing, 4 phyla and 13 genera were identified. The dominant bacterial phylum was Proteobacteria, and its relative abundance was between 52.5% and 70.6%. The overall trend of the relative abundance of Proteobacteria decreased on the time scale (P<0.05), and its relative abundance in the surface and middle layers was higher than that of the bottom layer on the spatial scale (P<0.05). There was no difference in the proportion of Proteobacteria between the surface and middle layers (P>0.05), and the abundance of its bottom layer was relatively stable; eight genera of bacteria with denitrification function were identified, among which the dominant bacterial genera (relative abundance>1%) were Dechloromonas and Pseudomonas. The relative abundance of Dechloromonas showed a trend of first decreasing and then increasing on the time scale, whereas the relative abundance of Pseudomonas showed a trend of increasing first and then decreasing on the time scale. There were no differences on the spatial scale between these two genera (P>0.05); the changes in bacterial diversity and abundance were basically similar, with a trend of first increasing and then decreasing on the time scale. The highest diversity and abundance of the bacterial community gradually increased with increasing depth on the spatial scale. ② ρ(TN) of the reservoir during stratification was 2.35-2.91 mg·L-1, and the nitrogen pollution was more serious. In March and April, ρ(TN) on the vertical scale was basically similar and showed a decreasing trend. In May, the content of total nitrogen was higher than that in March and April, and the highest value of total nitrogen content occurred in the surface layer. ③ Redundancy analysis showed that water temperature, dissolved oxygen, nitrate, and ammonia nitrogen were the main driving factors, and ammonia nitrogen showed a significantly negative correlation with Dechlormonas. In summary, the study of nirS-type denitrification communities and related influencing factors will contribute to analyzing the characteristics of denitrifying bacterial community changes in a micro-polluted drinking water reservoir and provide a theoretical research basis for the biological remediation of nitrogen pollution in such reservoirs in the future.


Assuntos
Bactérias , Desnitrificação , Bactérias/genética , Nitratos , Nitrogênio/análise , Qualidade da Água
10.
J Hazard Mater ; 411: 125021, 2021 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-33476910

RESUMO

A novel dual functional composite (MOFL-TpBD) was prepared through solvothermal methods, with excellent Pb2+ ions separation and stable 2,4,6-Trinitrophenol (TNP) fluorescence detection performance. MOFL-TpBD was characterized by FTIR, XRD, XPS, SEM and TGA et al. The prepared material was used to extract Pb2+ ions, with an adsorption capacity of 21.74 mg g-1 calculated by Langmuir isotherm model. The limit of detection was 0.32 µg L-1, along with a linear range from 0.7 to 12 µg L-1 and a precision of 5.4% (1 µg L-1, n = 9), respectively, where MOFL-TpBD was adopted as adsorbent for Pb2+ ions preconcentration. The practical samples and reference water sample were measured by the provided method, with the satisfactory recoveries (91-110%) and reliable analytical results. MOFL-TpBD was capable of fluorescent sensing of TNP, with a linear range from 0.01 to 1 mM and a limit of detection of 3.52 µM, respectively, and a precision of 3.29% was obtained (0.2 mM, n = 11). Meanwhile, the recoveries ranged from 91% to 108% in analysis of TNP for the practical samples. The designed material provided a potential candidate material for the detection of heavy metal ions and explosives in environmental water samples.

11.
Sci Total Environ ; 764: 144388, 2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33387764

RESUMO

Selective adsorption via the size matching effect is one of the most effective strategies for separating and analyzing low levels of organic molecules. Herein, multicomponent covalent organic frameworks (MC-COFs) with tunable pore sizes are constructed by using one knot (1,3,5-triformylphloroglucinol, Tp) and two organic linkers (p-phenylenediamine, Pa; benzidine, BD). The pore sizes of the MC-COFs composed of TpPaBDX (X = [BD]/([Pa] + [BD]) × 100 = 0, 25, 50, 75, and 100) range from 0.5-1.5 to 0.5-2.2 nm due to variations in the initial organic linker ratios. When coupling TpPaBDX-based solid-phase microextraction (SPME) with constant flow desorption ionization mass spectrometry (CFDI-MS), these MC-COFs feature better selective adsorption performance for tetrabromobisphenol A (TBBPA) derivatives than TpPa with a smaller pore size, TpBD with a larger pore size and even some commercial fibers (e.g., polydimethylsiloxane/divinylbenzene (PDMS/DVB)-, polyacrylate (PA)- and PDMS-coated fibers). The improved method involving MC-COF TpPaBD50 also presents favorable stability with relative standard deviations (RSD, 1 µg L-1) for single fibers of 5.5-7.9% (n = 7) and fiber-to-fiber of 6.6-7.8% (n = 7). Due to the decreased limits of detection and quantification (0.5-12 and 1.6-40 ng L-1), and reduced separation and detection time (7 min), ultratrace levels of TBBPA derivatives in real water samples are successfully detected. The proposed method shows great potential for the rapid tracing of the distribution, transportation and transformation of TBBPA derivatives to better understand their ecotoxicological effects in environmental media.

12.
ACS Appl Mater Interfaces ; 13(36): 43668-43675, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34473482

RESUMO

The efficient recognition of circulating tumor cells (CTCs) with an aptamer probe confers numerous benefits; however, the stability and binding affinity of aptamers are significantly hampered in real biological sample matrices. Inspired by the efficient preying mechanism by multiplex tubing feet and endoskeletons of sea urchins, we engineered a superefficient biomimetic single-CTC recognition platform by conjugating dual-multivalent-aptamers (DMAs) Sgc8 and SYL3C onto AuNPs to form a sea urchin-like nanoprobe (sea urchin-DMA-AuNPs). Aptamers Sgc8 and SYL3C selectively bind with the biomarker proteins PTK7 and EpCAM expressed on the surface of CTCs. CTCs were captured with 100% efficiency, followed by sorting on a specially designed multifunctional microfluidic configuration, integrating a single-CTC separation unit and a hydrodynamic filtrating purification unit. After sorting, background-free analysis of biomarker proteins in single CTCs was undertaken with inductively coupled plasma mass spectrometry by measuring the amount of 197Au isotope in sea urchin-DMA-AuNPs. With respect to a single-aptamer nanoprobe/-interface, the dual-aptamer nanoprobe improves the binding efficiency by more than 200% (Kd < 0.35 nM). The microchip facilitates the recognition of single CTCs with a sorting separation rate of 93.6% at a flow rate of 60 µL min-1, and it exhibits 73.8 ± 5.0% measurement efficiency for single CTCs. The present strategy ensures the manipulation and detection of a single CTC in 100 µL of whole blood within 1 h.


Assuntos
Aptâmeros de Nucleotídeos/química , Separação Celular/métodos , Ácidos Nucleicos Imobilizados/química , Dispositivos Lab-On-A-Chip , Nanopartículas Metálicas/química , Células Neoplásicas Circulantes/química , Materiais Biomiméticos/química , Moléculas de Adesão Celular/química , Linhagem Celular Tumoral , Molécula de Adesão da Célula Epitelial/química , Ouro/química , Humanos , Espectrometria de Massas , Técnicas Analíticas Microfluídicas/métodos , Receptores Proteína Tirosina Quinases/química
13.
Nat Plants ; 7(2): 129-136, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33594262

RESUMO

MicroRNA168 (miR168) is a key miRNA that targets Argonaute1 (AGO1), a major component of the RNA-induced silencing complex1,2. Previously, we reported that miR168 expression was responsive to infection by Magnaporthe oryzae, the causal agent of rice blast disease3. However, how miR168 regulates immunity to rice blast and whether it affects rice development remains unclear. Here, we report our discovery that the suppression of miR168 by a target mimic (MIM168) not only improves grain yield and shortens flowering time in rice but also enhances immunity to M. oryzae. These results were validated through repeated tests in rice fields in the absence and presence of rice blast pressure. We found that the miR168-AGO1 module regulates miR535 to improve yield by increasing panicle number, miR164 to reduce flowering time, and miR1320 and miR164 to enhance immunity. Our discovery demonstrates that changes in a single miRNA enhance the expression of multiple agronomically important traits.


Assuntos
Magnoliopsida/genética , MicroRNAs/genética , Oryza/genética , Melhoramento Vegetal/métodos , Imunidade Vegetal/genética , Plantas Geneticamente Modificadas/genética , RNA de Plantas/genética , China , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Supressão Genética
14.
Theor Appl Genet ; 121(5): 907-17, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20523963

RESUMO

The universal stress proteins (USPs) play an important role in enhancing survival rate during prolonged exposure to heat shock, nutrient starvation, or stressors from agents that arrest cell growth or damage DNA structures. Searching the HarvEST database of barley resulted in 25 putative USP cDNA sequences. Of these, 16 could translate into intact proteins (putative USPs). The alignments of multiple amino acid sequences between the putative barley USPs with those of Arabidopsis and Methanococcus jannaschii resulted in a set of common residues involved in ATP-binding. The 16 putative USPs in barley and the 21 in Arabidopsis were clustered into seven groups, which were distinct from those of E. coli. The genes in these different groups have different intron/exon structures. Nine putative USP genes of barley were cloned successfully based on their sequence characteristics, and they contain two or three introns each. Two of these introns were present in all the genes, one located between beta2 and alpha2, and the other between beta 4 and alpha 4. Five sets of primers were successfully developed for these putative USP genes. Two of them were mapped on chromosome 1H and the other three were located on three different chromosomes, 2H, 3H and 6H, respectively. Expression analyses were carried out for nine of these putative USP genes. The expression for two of them was undetectable within 27 h following exposure to salt stress. Six of the other seven were expressed in both root and leaf, and the remaining one was expressed in root only. The majority of these genes was expressed more in the salt-sensitive variety, Morex, than in the more tolerant variety, Steptoe.


Assuntos
Genes de Plantas/genética , Proteínas de Choque Térmico/genética , Hordeum/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Arabidopsis/genética , Mapeamento Cromossômico , Sequência Conservada/genética , Éxons/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/metabolismo , Íntrons/genética , Dados de Sequência Molecular , Filogenia , Folhas de Planta/genética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Estrutura Secundária de Proteína , Alinhamento de Sequência , Especificidade da Espécie
15.
Hereditas ; 147(1): 18-26, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20416013

RESUMO

Specific primers were designed to amplify the sequences of Hina genes from 121 wild barley (Hordeum spontaneum) accessions belonging to 18 populations from Iran, Israel and Turkey. Forty-nine single nucleotide polymorphisms (SNPs), nine indels, and 26 haplotypes were determined by sequence analysis. The genetic polymorphism (P), genetic diversity (He), and Shannon's information index (I) in the 18 populations were 0.486, 0.181 and 0.269, respectively. Approximately 2/3 genetic variations of Hina genes were presented within populations, while approximately 1/3 genetic variations were observed between populations. Broad gene flow (Nm= 3.31) and low genetic variation (Gst= 0.0702) were detected. However, the genetic differentiation between populations was independent of geographical distances according to the Mantel test (p = 0.478). The result of Spearman rank correlations (r(s)) showed that the genetic indices (P, He and I) of Hina were not significantly correlated with ecological factors. Only eight SNP positions correlated significantly with ecological factors. Of the eight SNP positions that positively correlated with ecological factors, only one SNP (769, T-C) was located in the coding region; however, it was not responsible for the amino acid change.


Assuntos
Genes de Plantas/genética , Hordeum/genética , Polimorfismo de Nucleotídeo Único , Sequência de Bases , DNA de Plantas/química , DNA de Plantas/genética , Ecologia , Variação Genética , Genética Populacional , Haplótipos , Hordeum/classificação , Hordeum/crescimento & desenvolvimento , Mutação INDEL , Irã (Geográfico) , Israel , Filogenia , Reação em Cadeia da Polimerase , Locos de Características Quantitativas/genética , Análise de Sequência de DNA , Especificidade da Espécie , Turquia
16.
Talanta ; 203: 210-219, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31202328

RESUMO

A magnetic functionalized bio-sorbent based on aptamer was designed for the selective separation of ultra-trace Pb2+, shortly termed as Fe3O4@Au@DNA. Pb(II) specific aptamer attached to the magnetic solid substrate served as affinity probe to capture and separate trace lead. Oligonucleotides with a polyA block were employed for the immobilization on the surface of AuNPs, with adenine sequences (polyA) as the part of effective anchoring block. The prepared Fe3O4@Au@DNA composites were characterized by FT-IR, SEM and XPS. The binding of lead on Fe3O4@Au@DNA composites surface was pH-dependent, the adsorption follows Langmuir model, and the adsorption dynamic fits the pseudo-second-order kinetics model. Procedure for lead separation and preconcentration was explored and combined with detection of graphite furnace atomic absorption spectrometry (GFAAS). Under the optimum condition, an enrichment factor of 17.73 was obtained with a sample volume of 1.0 mL. The limit of detection (LOD) was 57 ng L-1 along with a relative standard deviation (RSD) of 2.06 (n = 9). The procedure was further validated by a certified reference material GBW08608 and several environmental and blood samples.


Assuntos
Aptâmeros de Nucleotídeos/química , DNA/química , Chumbo/sangue , Nanopartículas de Magnetita/química , Espectrofotometria Atômica/métodos , Poluentes Químicos da Água/análise , Adsorção , Ouro/química , Humanos , Lagos/análise , Chumbo/química , Limite de Detecção , Concentração Osmolar , Poluentes Químicos da Água/química
17.
Org Lett ; 21(5): 1374-1378, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30763106

RESUMO

The biosynthetic gene clusters for herbicidins ( hbc) and aureonuclemycin ( anm) were identified in Streptomyces sp. KIB-027 and Streptomyces aureus, respectively. The roles of genes possibly involved in post-core-assembly steps in herbicidin biosynthesis in these clusters and a related her cluster were studied. Through systematic gene deletions, structural elucidation of the accumulated intermediates in the mutants, and in vitro verification of the encoded enzymes, the peripheral modification pathway for herbicidin biosynthesis is now fully established.


Assuntos
Antibacterianos/química , Nucleosídeos de Purina/biossíntese , Streptomyces/química , Estrutura Molecular
18.
Oncol Lett ; 13(6): 4341-4348, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28599436

RESUMO

WEE1 is a serine/threonine protein kinase that inactivates cell division cycle 2 and is therefore a critical cell cycle regulator. Increased WEE1 expression has been observed in numerous types of human malignancies, including hepatocellular carcinoma and melanoma. WEE1 inhibition also results in evident anti-tumor effects in several human tumor cells including colon cancer cells, suggesting WEE1 as a potential therapeutic target for the treatment of cancer. However, the expression pattern of WEE1 in colorectal cancer (CRC) remains unclear. In the present study, WEE1 mRNA expression in 43 cases of CRC tissues matched with adjacent normal tissues was determined by reverse-transcription quantitative polymerase chain reaction. The results demonstrated that WEE1 mRNA expression was significantly increased in CRC tissues and that this upregulation correlated significantly with hepatic metastasis, distant metastasis and high tumor node metastasis (TNM) stage of CRC. Additionally, WEE1 protein in 102 CRC tissue samples was detected by immunohistochemistry, and positive staining of WEE1 was identified in more than half of patients with CRC. WEE1 staining scores were also observed to be associated with distant metastasis and high TNM stage of CRC. In addition, patients with CRC with high WEE1 staining score (2+ or 3+) exhibited either poorer overall survival or poorer disease-free survival compared with those with low WEE1 staining score (0 or 1+). The multivariable Cox model also identified a high WEE1 staining score as well as high TNM stage to be independent prognostic factors for CRC. In conclusion, WEE1 upregulation is associated with a high degree of malignancy and poor prognosis of CRC, suggesting WEE1 as a potential prognostic biomarker for CRC.

19.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(3): 1848-9, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-25329268

RESUMO

The complete mitochondrial genome of Platysmacheilus nudiventris (Teleostei, Cyprinidae, Gobioninae), an endemic Chinese cyprinid fish, was first determined by DNA sequencing based on the PCR fragments. The total length of the mitochondrial genome is 16,603 bp, including 22 transfer RNA genes, 2 ribosomal RNA genes, 13 protein-coding genes and a non-coding control region (D-loop). The overall-based composition is 30.2% A, 26.9% T, 16.7% G and 26.1% C, with high A+T content (57.1%). The results will provide useful data for further studies on species identification, evolutionary and population genetic studies of P. nudiventris and its related species.


Assuntos
Cyprinidae/genética , Genoma Mitocondrial , Animais , Composição de Bases/genética , Sequência de Bases , DNA Mitocondrial/genética , Genes Mitocondriais , RNA de Transferência/genética
20.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(3): 1904-5, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-25319287

RESUMO

In this study, the complete mitochondrial DNA genome sequence of Xenophysogobio nudicorpa was first determined by DNA sequencing based on the PCR fragments. The complete mitochondrial DNA (mtDNA) genome sequence of X. nudicorpa is a circular molecule of 16,616 bp in length. It consists of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a control region (D-loop). The gene nucleotide composition of X. nudicorpa is 30.5% A, 26.0% C, 16.8% G, and 26.7% T, with a relatively high A+T content (57.2%). The results could provide useful data for studying genetic diversity and phylogenetics in X. nudicorpa and related species.


Assuntos
Cyprinidae/genética , Genoma Mitocondrial , Animais , Composição de Bases/genética , Pareamento de Bases/genética , Sequência de Bases , DNA Mitocondrial/genética , RNA de Transferência/genética
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