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1.
Huan Jing Ke Xue ; 41(2): 529-536, 2020 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608712

RESUMO

To gain a better understanding of the day-night variation characteristics of water-soluble ions, PM2.5 samples were continuously collected for two months in the Nanjing Jiangbei New Area during winter. The diurnal variation and sources of water-soluble ions were studied. Results showed that the mass concentration of water-soluble ions ranged from 17.07 µg·m-3 to 168.43 µg·m-3 with a mean value of (59.01±30.75) µg·m-3. The average mass concentration of water-soluble ions in daytime was higher than that in the nighttime. The concentration ratio of NO3- and NH4+ to total ion concentrations was higher at night, while SO42- and Cl- were higher during daytime. SO42-, NO3-, and NH4+ (SNA) were the dominant species of water-soluble ions in PM2.5 in Nanjing. The mass concentration of SNA on polluted days was higher than that on clean days. The ratio of the anion-cation balance (AE/CE) was larger than 1, indicating that the PM2.5 was acidic. There was a significant linear correlation between NH4+ with NO3- and SO42-, indicating that it occurred mainly in the form of NH4NO3 and (NH4)2SO4 in PM2.5. The PMF source apportionment indicated that water-soluble ions of PM2.5 were mainly derived from motor vehicle emissions, fossil fuel combustion, biomass burning, and dust in the Nanjing Jiangbei New Area.

2.
Huan Jing Ke Xue ; 41(2): 647-655, 2020 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608723

RESUMO

Chemical and deposition characteristics as well as potential sources of precipitation in Xi'an from 2000 to 2017 were analyzed based on the acid deposition monitoring network in East Asia (EANET). The pH of precipitation showed increasing trends, whereas the conductivity of precipitation showed decreasing trends between 2000 and 2017 in Xi'an. The decreasing order of ion concentration in precipitation was as follows:SO42- > Ca2+ > NH4+ > NO3- > Na+ > Cl- > Mg2+ > K+. The percentage of SO42- in the total ion concentration decreased from 38.6% in 2000 to 27.9% in 2017. The ratio of SO42- to NO3- in recent years indicated that the type of pollutant in Xi'an changed from the coal-burning type to the mixed type. The deposition of SO42- in precipitation had a declining trend, which was consistent with the results of the Mann-Kendall test. Nitrogen and sulphur depositions in precipitation were 16.89 kg·(hm2·a)-1 and 33.52 kg·(hm2·a)-1, respectively, and ammonium nitrogen (NH4+-N) was the main deposition component of atmospheric active nitrogen in the precipitation of Xi'an. Vehicle emissions were the major contributors to SO42- (15.43%) and NO3- (72.99%). NH4+ originated mainly from agriculture sources, and the percentage reached up to 75.47%.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32496756

RESUMO

Recently, room-temperature flexible gas sensors have been widely studied because they can operate without being heated and create low-cost, low-power-consumption devices with long-term stability. Here, by designing the active material composition and structure, we report an electrospun carbon nanofiber (CNF) network grafted by two-dimensional MoS2 nanosheets and embedded CoS2 nanoparticles, which serves as a flexible gas sensor for various toxic or hazardous gases working at room temperature. In particular, the CNFs/CoS2/MoS2 hybrid films exhibit very high selectivity toward NO over other gases including NO2 and CH4, with selectivity coefficients (|SNO/SNO2| and |SNO/SCH4|) as high as 43 and 42 (defined as the ratio of responses between two gases). The sensor shows a linear relationship in the gas concentration range of 1-100 ppm and a stable response during repeated bending. Theoretical calculations suggest that MoS2 can be selectively n-doped by NO, while CoS2 can effectively capture NO molecules, leading to enhanced selectivity and sensitivity. Our large-area flexible sensors made by synergistic design have potential applications in biological and environmental areas for low-cost, selective detection of toxic or targeted gases.

4.
J Hazard Mater ; 400: 123116, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32569980

RESUMO

Microbial induced carbonate precipitation (MICP) is known as a significant process for remediating heavy metals contaminated environment. In this study, a novel Cd-resistant ureolytic bacteria was isolated and identified as Enterobacter sp. Its performances for immobilizing Cd in solution and soil were systematically discussed at different treatment conditions. Results showed that initial pH and Cd concentration were important parameters to influence Cd removal rate. The maximal Cd removal rate in solution reached 99.50 % within 7 days by MICP. The precipitation produced in Cd removal process were characterized by X-ray diffraction, scanning electron microscopy and energy dispersive spectrometer to understand the removal mechanism. Analyses showed that Cd removal mechanism of CJW-1 was predominately via biominerals including calcites and vaterites to absorb Cd2+. Cd immobilization tests demonstrated that the highest Cd-immobilization rate in soil could reach 56.10 %. Although all treatments contribute to soil pH, fertility, and enzyme activities improvement, oyster shell wastes (OS) had a better effect on soil cation exchange capacity. All treatments had negative effects on soil respiration and bacterial community, but OS can alleviate such adverse influence. Our results emphasized that Cd-resistant ureolytic bacteria strain CJW-1 combined with OS had excellent ability and reuse value to remediate Cd-contaminated environment.

5.
Bioinformatics ; 36(11): 3610-3612, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32170933

RESUMO

SUMMARY: Although many quantitative structure-activity relationship (QSAR) models are trained and evaluated for their predictive merits, understanding what models have been learning is of critical importance. However, the interpretation and visualization of QSAR model results remain challenging, especially for 'black box' models such as deep neural network (DNN). Here, we take a step forward to interpret the learned chemical features from DNN QSAR models, and present VISAR, an interactive tool for visualizing the structure-activity relationship. VISAR first provides functions to construct and train DNN models. Then VISAR builds the activity landscapes based on a series of compounds using the trained model, showing the correlation between the chemical feature space and the experimental activity space after model training, and allowing for knowledge mining from a global perspective. VISAR also maps the gradients of the chemical features to the corresponding compounds as contribution weights for each atom, and visualizes the positive and negative contributor substructures suggested by the models from a local perspective. Using the web application of VISAR, users could interactively explore the activity landscape and the color-coded atom contributions. We propose that VISAR could serve as a helpful tool for training and interactive analysis of the DNN QSAR model, providing insights for drug design, and an additional level of model validation. AVAILABILITY AND IMPLEMENTATION: The source code and usage instructions for VISAR are available on github https://github.com/qid12/visar. CONTACT: shaoli@mail.tsinghua.edu.cn. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

6.
J Hazard Mater ; 388: 122065, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31954306

RESUMO

Bioremediation of cadmium polluted soil using biochar (BC) and plant growth promotion bacteria (PGPB) have been widely concerned. In our study, a novel Cd immobilizing PGPB strain TZ5 was isolated based on the Cd immobilizing potential and plant growth promotion (PGP) traits. Further, changes of surface morphology and functional groups of TZ5 cells were observed after exposed to Cd2+ by SEM-EDS and FTIR analyses. Then, the strain TZ5 was successfully loaded on BC as biochemical composites material (BCM). Pot experiment indicated that the percentage of acetic acid-extractable Cd in BCM treatments significantly decreased by 11.34 % than control. Meanwhile, BCM significantly increased the dry weight of ryegrass by 77.78 %, and decreased the Cd concentration of ryegrass by 48.49 %, compared to control. Microbial counts and soil enzyme activities in rhizosphere were both significantly improved by BCM. Furthermore, the proportion of relative abundance of Bacillus genus was enhanced after treated by BCM, which indicated that the strain TZ5 was successfully colonized in the rhizosphere. This study provided a practical strategy for bioremediation of Cd contaminated soil.

7.
J Hazard Mater ; 382: 121093, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31476721

RESUMO

In-situ passivation of soil chromium (Cr) contamination based on chemical and biological passivators has been widely concerned, however, the cooperative effect of two types of passivators on Cr passivation and soil properties was little investigated. In this study, nano zero valent iron (nZVI) and humic acid (HA) as the chemical passivators were selected and were combined with a novel Cr resistant strain QY-1 to study these two points. Results demonstrated that the combination was more effective in Cr immobilization, among which, HA + QY-1 had the highest passivation rate (82.83%), followed by nZVI + QY-1. HA + QY-1 alleviated soil Cr stress most efficiently as its soil relevant fertility indicators, microbial quantity, respiration and seed gemination rate significantly increased. On the contrary, nZVI decreased soil respiration and microbial abundance, but the addition of QY-1 could relieve this phenomenon. The results highlighted the ability of HA + QY-1 to remediate Cr contaminated soil and improve soil stability.

8.
Chemosphere ; 239: 124706, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31493754

RESUMO

The remediation effect of organic acids in heavy metal contaminated soil was widely studied. However, the comprehensive evaluation of organic acids on micro-ecological environment in heavy metal contaminated soil was less known. Herein, this experiment was conducted to investigate the impact of malic acid, citric acid and oxalic acid on soil fertility, cadmium (Cd) speciation and ecotoxicity in contaminated soil. Especially, to evaluate the ecotoxicity of Cd, high-throughput sequencing was used to investigate the soil bacterial community structure and diversity after incubation with organic acids. The results showed that obvious changes in soil pH were not observed. Whereas, the contents of available phosphorus (Olsen-P) and alkali hydrolysable nitrogen (Alkeline-N) evidently increased with a significant difference. Furthermore, compared to control, the proportion of acetic acid-extractable Cd increased by 3.06-6.63%, 6.11-9.43% and 1.91-6.22% respectively in the groups amended with malic acid, citric acid and oxalic acid, which indicated that citric acid did better in improving the availability of Cd than malic acid and oxalic acid. In terms of biological properties, citric acid did best in bacteria count increase, enzyme activities and bacterial community structure improvement. Accordingly, these results provided a better understanding for the influence of organic acids on the micro-ecological environment in Cd contaminated soil, based on physicochemical and biological analysis.


Assuntos
Cádmio/toxicidade , Ácidos Carboxílicos/farmacologia , Recuperação e Remediação Ambiental/métodos , Microbiologia do Solo , Poluentes do Solo/química , Bactérias/efeitos dos fármacos , Cádmio/análise , Cádmio/química , Ácidos Carboxílicos/química , Ácido Cítrico/química , Ácido Cítrico/farmacologia , Ecotoxicologia , Poluição Ambiental/análise , Malatos/química , Malatos/farmacologia , Ácido Oxálico/química , Ácido Oxálico/farmacologia , Solo/química , Poluentes do Solo/análise
9.
Environ Pollut ; 255(Pt 2): 113252, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31542610

RESUMO

To develop a high efficient and eco-friendly approach to remediate cadmium (Cd) contaminated soil, we designed the activation and extraction systems, on the basis of combined effects between the ability of organic acids to activate Cd and the ability of mushroom accumulator (Lentinus edodes) to extract Cd. The results showed that the proportion of acetic acid-extractable Cd significant increased with the application of exogenous organic acids. Additionally, soil microecology analysis indicated that exogenous organic acids evidently enhanced the numbers of microbial cells and the activities of soil enzymes. Besides, high throughput sequencing analysis revealed exogenous organic acids improved the diversity and structure of soil bacterial community after remediation. Particularly, the combination application of mushroom and exogenous citric acid had highest accumulation efficiency of Cd, and its efficiency was 59.19% higher than single mushroom treatment. Hence, exogenous organic acids could alleviate soil microecology and increase mycoextraction efficiency, which suggested it was a feasible route to remediate Cd contaminated soil by the activation and extraction systems.


Assuntos
Cádmio/química , Poluentes do Solo/metabolismo , Agaricales , Bactérias , Biodegradação Ambiental , Cádmio/análise , Compostos Orgânicos , Cogumelos Shiitake , Solo/química , Poluentes do Solo/análise
10.
Environ Pollut ; 252(Pt A): 553-561, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31181500

RESUMO

Remediation of soil chromium (Cr) pollution is becoming more and more urgent. In this study, a multi-loaded nano-zero-valent iron (nZVI) material (CNH) was prepared by carboxymethyl cellulose (CMC) and humic acid (HA) as dispersant and support agent, respectively, and the remediation effect of CNH, HA and CN (CNH without HA) for Cr contaminated soil was investigated within 90 d cycle. After 7 d treatment of CNH, the HOAc-extractable Cr decreased significantly. After the 90 d remediation, the HOAc-extractable Cr decreased most in the treatment of 3% CNH, about 74.48% lower than control. All treatments eventually caused different decline of soil pH, with a range of 0.12-0.54, in which the CNH treatment group had the least depression. HA loading significantly weakened the toxicity of nZVI, resulting in the higher soil microbial quantity and enzyme activities compared with CN. Additionally, the improvement of soil microecology by CNH and HA was positively correlated with the ratio of application, while CN was negatively correlated (except FDA enzyme activity) with these indexes. These results emphasized the potential of the synthesized CNH as a promising material to remediate Cr contaminated soil. Furthermore, details of possible mechanistic insight into the Cr remediation were carefully discussed.


Assuntos
Cromo/química , Poluição Ambiental/análise , Recuperação e Remediação Ambiental/métodos , Ferro/química , Poluentes do Solo/análise , Solo/química , Carboximetilcelulose Sódica , Substâncias Húmicas , Microbiologia do Solo
11.
3 Biotech ; 9(5): 166, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30997303

RESUMO

The zinc finger protein (ZFP) transcription factor family plays an important role in regulating plant growth, development, and response to abiotic stress. In this study, we aimed to determine the role of GmZAT4, a C2H2-type transcription factor, in abiotic stress tolerance. The complete coding sequence of the GmZAT4 gene was isolated from soybean root RNA, which shows highest expression level compared with leaf, flower and other tissues. Using multiple sequence alignment and conserved domain analysis, we showed that GmZAT4 is a typical C2H2-type transcription factor which is comprised of two C2H2 domains, including a highly conserved QALGGH motif, and implied the regulation of abiotic stress tolerance in plant. A phylogenetic tree revealed that the soybean GmZAT4 gene clustered with ZAT4 from Glycine soja and AZF1, AZF2, and AZF3 from Arabidopsis thaliana. The mRNA expression levels of GmZAT4 were determined in two soybean cultivars by quantitative reverse transcription (qRT)-PCR and compared. The results showed higher expression (up to 60, 25 and 4 times, respectively) in the drought-tolerant type (Jinda 74) compared to the drought-sensitive soybean cultivar (Jinda 53) following treatment with 18% PEG, 150 mM NaCl, or 100 µM abscisic acid (ABA). GmZAT4 was ectopically over-expressed in A. thaliana to determine its role in abiotic stress tolerance. GmZAT4 overexpression enhanced the tolerance of A. thaliana to treatment with 20% PEG and 150 mM NaCl, and improved the germination rate following treatment with 1 µM or 2 µM ABA. The expression profiles of marker genes in the ABA signaling pathway, such as RD29A, RD29B, ABI, and RAD, indicated that GmZAT4 enhanced the abiotic stress tolerance of Arabidopsis. These results suggest that the C2H2-type ZFP encoded by GmZAT4 plays an important role in PEG and NaCl stress tolerance and ABA responses in soybean and A. thaliana.

12.
Chemosphere ; 228: 44-53, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31022619

RESUMO

Although iron nanoparticles (NPs) have been used for environmental remediation of heavy metal, their potential to remediate lead (Pb) contaminated soil and effect on soil micro-ecology is unclear. The purpose of this study was to investigate the potential of nanoscale zerovalent iron (nZVI), nanoscale zerovalent iron supported by biochar (nZVI@BC), ferrous sulfide (FeS-NPs), ferrous sulfide supported by biochar (FeS-NPs@BC), ferriferrous oxide (Fe3O4-NPs) and ferriferrous oxide supported by biochar (Fe3O4-NPs@BC) to remediate Pb contaminated soil and the influences for soil micro-ecology. The results showed that biochar (BC) could improve the crystal shape and superficial area of iron-based nanoparticles. Soil pH values was significantly decreased by FeS-NPs and FeS-NPs@BC, but increased by other iron-nanoparticles. The ability to reduce available Pb concentration showed significant difference among these iron-nanoparticles, that is, the immobilized rate were nZVI by 45.80%, nZVI@BC by 54.68%, FeS-NPs by 2.70%, FeS-NPs@BC by 5.13%, Fe3O4-NPs by 47.47%, Fe3O4-NPs@BC by 30.51% at day 90. Almost all soil enzyme activities in Fe3O4-NPs and Fe3O4-NPs@BC groups were increased, but the majority of the enzyme activities were inhibited in other iron-based nanoparticles groups, while the maximum bacterial number was determined in FeS-NPs group. Furthermore, microbial diversity analysis showed that FeS-NPs has significantly changed microbial community richness and diversity, followed by nZVI and Fe3O4-NPs. Accordingly, our results suggested that nZVI@BC had the best immobilization effect on Pb in high-concentration Pb-contaminated alkaline soil, but the toxic effect of Fe3O4-NPs on soil micro-ecology was relatively minimal.


Assuntos
Recuperação e Remediação Ambiental/métodos , Ferro/química , Chumbo/análise , Nanopartículas , Poluentes do Solo/química , Bactérias/citologia , Bactérias/enzimologia , Carvão Vegetal , Compostos Ferrosos , Ferro/análise , Nanopartículas/química , Solo/química , Poluentes do Solo/análise
13.
Ecotoxicol Environ Saf ; 166: 116-122, 2018 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-30253286

RESUMO

Although the effect of heavy metal on soil microbial diversity was widely studied, the interaction among micro-ecological environment in heavy metal contaminated soil was less known. In this study, we systematically investigated the influence of cadmium (Cd) on soil micro-ecological environment (pH, nutrient content, soil enzyme activities, microbial biomass, bacterial and fungal diversities). Results showed that pH values slightly decreased with the Cd level increase, whereas the nutrient content including of Olsen-P (OSP), Alkeline-N (ALN), Olsen-K (OSK) and organic matter (OM) did not show significant difference in different treatments. In contrast to physicochemical properties, the biochemical qualities were easily influenced by Cd pollutant, resulting in soil microbial numbers and enzyme activities significantly decreased. High-throughput sequencing showed that microbial community composition was significantly affected by heavy metal. For bacteria, Actinobacteria abundance significantly decreased in Cd treated soil, corresponding to Proteobacteria and Firmicutes increased. For fungi, the most dominant phyla member (Ascomycota) was significantly decreased whereas Zygomycota significantly increased with Cd addition. These results further revealed the integral interrelation of micro-ecology environmental players under the stress of different Cd levels.


Assuntos
Cádmio/análise , Metais Pesados/análise , Microbiota/efeitos dos fármacos , Microbiologia do Solo , Poluentes do Solo/análise , Bactérias/efeitos dos fármacos , Biomassa , Ecologia , Fungos/efeitos dos fármacos , Solo/química
14.
Environ Pollut ; 240: 717-724, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29778057

RESUMO

In this study, the dynamic Cr(VI) removal process from water by the synthesized multilayer material coated nanoscale zerovalent iron (SBC-nZVI) was systematically discussed at different treatment conditions. The results showed that initial pH, contact time, Cr(VI) concentration and the dosage of SBC-nZVI were important parameters that influenced the Cr(VI) removal efficiency. The major Cr(VI) removal occurred within 60 min and gradually tend to equilibrium with consistent treatment. The removal efficiency was highly depended on pH values and the adsorption kinetics agreed well with the pseduo-second-order model (PSO). When the initial Cr(VI) concentration was below 15 mg/L, the removal rate could reach to about 100%. Moreover, the removal efficiency increased with the increase of SBC-nZVI dosage, which related to the increase of reactive sites. To understand the removal mechanism, SBC-nZVI before and after reaction with Cr(VI) were characterized by fourier transform infrared spectra (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), and X-ray photoelectron spectroscopy (XPS). These analysis showed that the interaction of SBC-nZVI with Cr(VI) was mainly controlled by reduction and electrostatic attraction. Therefore, these results explained the interaction between Cr(VI) and SBC-nZVI material in detail, and further proved that SBC-nZVI could be an effective material to remove Cr(VI) from water.


Assuntos
Cromo/análise , Recuperação e Remediação Ambiental/métodos , Ferro/química , Poluentes Químicos da Água/análise , Água/química , Adsorção , Cinética , Microscopia Eletrônica de Varredura/métodos , Espectroscopia Fotoeletrônica/métodos , Difração de Raios X/métodos
15.
Int J Gynecol Cancer ; 28(2): 323-331, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29240605

RESUMO

OBJECTIVE: This study aimed to investigate whether platelet-derived growth factor D (PDGF-D) is a prognostic biomarker and is associated with platinum resistance in epithelial ovarian cancer, which has not been studied by others previously. METHODS: In this study, we detected expression of PDGF-D in ovarian cancer tissues through immunohistochemistry and Western blotting. Furthermore, we analyzed the association between PDGF-D expression and clinicopathological features including prognosis in epithelial ovarian cancer. Statistical analyses were performed by using χ test, log-rank test, Cox regression test, and Kaplan-Meier method. RESULTS: High PDGF-D expression is positively correlated with International Federation of Gynecology and Obstetrics stage (P < 0.001), histologic grade (P < 0.001), lymph node metastasis (P = 0.022), and poor prognosis (P < 0.001). Platelet-derived growth factor D in platinum-resistant cases is overexpressed compared with that in platinum-sensitive cases (P < 0.001). Obstetrics stage (P = 0.029) and PDGF-D overexpression (P < 0.001) are independently correlated with platinum resistance. CONCLUSIONS: Our study indicates that PDGF-D overexpression is an independent predictor of platinum-based chemotherapy resistance and that it may also be a potential biomarker for targeted therapy and poor prognosis.


Assuntos
Biomarcadores Tumorais , Carcinoma Epitelial do Ovário/diagnóstico , Resistencia a Medicamentos Antineoplásicos , Linfocinas/fisiologia , Neoplasias Ovarianas/diagnóstico , Fator de Crescimento Derivado de Plaquetas/fisiologia , Compostos de Platina/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/metabolismo , Feminino , Humanos , Linfocinas/metabolismo , Pessoa de Meia-Idade , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Fator de Crescimento Derivado de Plaquetas/metabolismo , Valor Preditivo dos Testes , Prognóstico , Adulto Jovem
16.
Curr Microbiol ; 75(3): 316-322, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29090322

RESUMO

A novel bacterial cells immobilized carrier (ZnONPs/PVA), polyvinyl alcohol (PVA) composites decorated with ZnO nanoparticles (ZnO NPs), was prepared and used for immobilization of the strain Ochrobactrum sp. LC-1, and subsequently for quinoline degrading in water. Characterization of ZnONPs/PVA by using X-ray diffractometer and scanning electron microscopy demonstrated that ZnO NPs were coated on the surface of PVA cubes evenly and the bacterium grew well on the ZnONPs/PVA. Quinoline biodegradation results showed that the degradation effect of quinoline by ZnONPs/PVA immobilized cells was superior to the free cells significantly. The structure and physical properties of ZnNPs/PVA were maintained steady after the reuse of ZnNPs/PVA for cells immobilization several times. Reusability of the ZnONPs/PVA immobilized cells revealed that the quinoline removal ratio was above 97% within 8 h under the conditions of pH neutral, 37 °C when the initial quinoline concentration was 300 mg/L.


Assuntos
Ochrobactrum/química , Ochrobactrum/metabolismo , Quinolinas/metabolismo , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Biodegradação Ambiental , Células Imobilizadas/química , Células Imobilizadas/metabolismo , Nanopartículas/química , Álcool de Polivinil/química , Quinolinas/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo , Óxido de Zinco/química
17.
Appl Plant Sci ; 5(7)2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28791202

RESUMO

PREMISE OF THE STUDY: Proso millet (Panicum miliaceum; Poaceae) is a minor crop with good nutritional qualities and strong tolerance to drought stress and soil infertility. However, studies on genetic diversity have been limited due to a lack of efficient genetic markers. METHODS: Illumina sequencing technology was used to generate short read sequences of proso millet, and de novo transcriptome assemblies were used to develop a de novo assembly of proso millet. Genic simple sequence repeat (SSR) markers were identified and used to detect polymorphism among 56 accessions. Population structure and genetic similarity coefficient were estimated. RESULTS: In total, 25,341 unique gene sequences and 4724 SSR loci were obtained from the transcriptome, of which 229 pairs of SSR primers were validated, which resulted in 14 polymorphic genic SSR primers exhibiting 43 total alleles. According to the ratio of polymorphic markers (6.1%, 14/229), there are potentially 288 polymorphic genic SSR markers available for genetic assay development in the future. Bayesian population analyses showed that the 56 accessions comprised two distinct groups. DISCUSSION: A genetic structure and cluster assay indicated that the accessions from the Loess Plateau of China shared a high genetic similarity coefficient with those from other regions and that there was no correlation between genetic diversity and geographic origin. The transcriptome sequencing data and millet-specific SSR markers developed in this study establish an excellent resource for gene discovery and may improve the development of breeding programs in proso millet in the future.

18.
Proc Natl Acad Sci U S A ; 114(19): 5047-5052, 2017 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-28439024

RESUMO

Members of the aquaporin (AQP) family have been suggested to transport aluminum (Al) in plants; however, the Al form transported by AQPs and the roles of AQPs in Al tolerance remain elusive. Here we report that NIP1;2, a plasma membrane-localized member of the Arabidopsis nodulin 26-like intrinsic protein (NIP) subfamily of the AQP family, facilitates Al-malate transport from the root cell wall into the root symplasm, with subsequent Al xylem loading and root-to-shoot translocation, which are critical steps in an internal Al tolerance mechanism in Arabidopsis We found that NIP1;2 transcripts are expressed mainly in the root tips, and that this expression is enhanced by Al but not by other metal stresses. Mutations in NIP1;2 lead to hyperaccumulation of toxic Al3+ in the root cell wall, inhibition of root-to-shoot Al translocation, and a significant reduction in Al tolerance. NIP1;2 facilitates the transport of Al-malate, but not Al3+ ions, in both yeast and Arabidopsis We demonstrate that the formation of the Al-malate complex in the root tip apoplast is a prerequisite for NIP1;2-mediated Al removal from the root cell wall, and that this requires a functional root malate exudation system mediated by the Al-activated malate transporter, ALMT1. Taken together, these findings reveal a critical linkage between the previously identified Al exclusion mechanism based on root malate release and an internal Al tolerance mechanism identified here through the coordinated function of NIP1;2 and ALMT1, which is required for Al removal from the root cell wall, root-to-shoot Al translocation, and overall Al tolerance in Arabidopsis.


Assuntos
Alumínio/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , Raízes de Plantas/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Transporte Biológico Ativo/fisiologia , Transportadores de Ânions Orgânicos/genética , Raízes de Plantas/genética
19.
Medicine (Baltimore) ; 95(42): e5164, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27759648

RESUMO

BACKGROUND: Stanford type-A acute aortic dissection (AAD) is a severe cardiovascular disease demonstrating the characteristics of acute onset and rapid development, with high morbidity and mortality. The available evidence shows that preoperative acute lung injury (ALI) induced by Stanford type-A AAD is a frequent and important cause for a number of untoward consequences. However, there is no study assessing the incidence of preoperative ALI and its independent determinants before Standford type-A AAD surgery in Chinese adult patients. METHODS/DESIGN: This is a prospective, double-blind, signal-center clinical trial. We will recruit 130 adult patients undergoing Stanford type-A AAD surgery. The incidence of preoperative ALI will be evaluated. Perioperative clinical baselines and serum variables including coagulation, fibrinolysis, inflammatory, reactive oxygen species, and endothelial cell function will be assayed. The independent factors affecting the occurrence of preoperative ALI will be identified by multiple logistic regression analysis. TRIAL REGISTRATION: ClinicalTrials.gov (https://register.clinicaltrials.gov/), Registration number NCT01894334.


Assuntos
Lesão Pulmonar Aguda/epidemiologia , Aneurisma Dissecante/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Complicações Intraoperatórias/epidemiologia , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Doença Aguda , Lesão Pulmonar Aguda/diagnóstico , Lesão Pulmonar Aguda/etiologia , Adolescente , Adulto , Idoso , Aneurisma Dissecante/diagnóstico , Aneurisma Dissecante/mortalidade , Aneurisma da Aorta Torácica/diagnóstico , Aneurisma da Aorta Torácica/mortalidade , China/epidemiologia , Método Duplo-Cego , Feminino , Seguimentos , Mortalidade Hospitalar/tendências , Humanos , Incidência , Complicações Intraoperatórias/diagnóstico , Complicações Intraoperatórias/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Adulto Jovem
20.
J Neurol Sci ; 368: 277-84, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27538649

RESUMO

Previous studies have shown that xenon-delayed postconditioning for up to 2h after reperfusion provides protection against spinal cord ischemia/reperfusion (I/R) injury in rats. This study was designed to determine the roles of phosphatidylinositol 3-kinase (PI3K)-Akt and extracellular signal-regulated kinase (ERK) in this neuroprotection. The rats were randomly assigned to the following nine groups (n=16∗9): 1) I/R+N2 group, 2) I/R+Xe group, 3) I/R+PD98059+N2 group (ERK blocking agent), 4) I/R+wortmannin+N2 group (PI3K-Akt blocking agent), 5) I/R+PD98059+Xe group, 6) I/R+wortmannin+Xe group, 7) I/R+DMSO+Xe group (dimethyl sulfoxide, vehicle control), 8) I/R+DMSO+N2 group, and 9) sham group (no spinal cord ischemia and no xenon). Spinal cord ischemia was induced for 25min in male Sprague-Dawley rats. Neurological function was assessed using the Basso, Beattie, and Bresnahan (BBB) open-field locomotor scale at 6, 12, 24 and 48h after reperfusion. Histological examination of the lumbar spinal cord was performed using Nissl staining and TUNEL staining at 4 (n=8) and 48 (n=8)h after reperfusion. Western blotting was performed to evaluate p-Akt and p-ERK expression in the spinal cord at 4 (n=8) and 48 (n=8) h after reperfusion. Compared with the sham group, all rats in the I/R groups had lower BBB scores, fewer normal motor neurons, more apoptotic neurons and lower p-Akt and p-ERK levels at each time point (P<0.05). Compared with the I/R group, rats in the I/R+Xe group had higher neurological scores, more normal motor neurons, fewer apoptotic neurons and significantly higher levels of p-Akt and p-ERK at each time point (P<0.05). Compared with the I/R+Xe group, the I/R+PD98059+Xe and I/R+wortmannin+Xe groups showed worse neurological outcomes and less p-Akt and p-ERK at each time point (P<0.05). These results suggest that xenon-delayed postconditioning improves neurological outcomes to spinal cord I/R injury in rats through the activation of the AKT and ERK signaling pathways.


Assuntos
Anestésicos Inalatórios/uso terapêutico , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Isquemia do Cordão Espinal/tratamento farmacológico , Xenônio/uso terapêutico , Animais , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Masculino , Ratos , Ratos Sprague-Dawley
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