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1

Edwardsiella ictaluri LuxS: activity, expression, and involvement in pathogenicity

100%
Zhang M., Sun L.
Polish Journal of Microbiology
|
2012
|
tom 61
|
nr 4
Edwardsiella ictaluri is a Gram-negative bacterium and the causative agent of enteric septicemia of catfish. In this study, we examined the expression and function of the LuxS from a pathogenic E. ictaluri strain, J901. J901 was found to produce autoinducer 2 (AI-2) activity that maximized at mid-logarithmic phase and was enhanced by glucose and repressed by high temperature. Consistently, a luxS gene (luxSEi) was identified in J901, whose expression was regulated by cell density, glucose, and temperature in a manner similar to that observed with AI-2 activity. Further analysis showed that LuxSEi is a biologically active AI-2 synthase that was able to complement the luxS-defective phenotype of Escherichia coli DH5. To examine the functional importance of LuxSEi, a genetically modified variant of J901, J901Ri, was constructed, in which luxSEi expression was blocked by RNA interference. Compared to the wild type, J901Ri was (i) reduced in AI-2 activity to a level of 59% of that of the wild type; (ii) impaired in both planktonic and biofilm growth; (iii) significantly attenuated in the ability to infect cultured fish cells and to cause mortality in infected fish; (iv) unable to induce the expression of certain virulence-associated genes. Addition of exogenous AI-2 failed to rescue the growth defect of J901Ri as free-living cells but restored biofilm production and the expression of virulence genes to levels comparable to those of the wild type. Taken together, these results indicate that LuxSEi is a functional AI-2 synthase that is required for optimal cellular growth and host infection.
2

Persulfate oxidation for the remediation of petroleum hydrocarbon-contaminated soils

81%
Wu H., Sun L., Wang H., Wang X.
Polish Journal of Environmental Studies
|
2016
|
tom 25
|
nr 2
The feasibility of total petroleum hydrocarbon-contaminated (TPH) soil remediation was studied using persulfate oxidation. Factors tested included type of activator, persulfate concentration, number of persulfate applications, and reaction time. Probe chemicals were used to study effi ciency of the persulfate oxidation mechanism. The best activation method used Fe2+, which achieved 40.8% TPH degradation at 24 h with an initial TPH concentration of 14,432.5 mg/kg. For alkaline (high pH) and hydrogen peroxide activation treatments, TPH degradation effi ciencies were 35.2% and 21%, respectively. Thermal activation effi ciency was relatively low (15.6%). Kinetic experiments demonstrated that the oxidation reaction was substantially completed within 60 min. A one-time addition of persulfate was superior to multiple applications. The addition of probe compounds produced sulfate radicals, hydroxyl radicals, and reductants. The results indicate that activated persulfate is reasonably effective for remediation of TPH-contaminated soils.
3

The dynamic changes of catechins and related genes in tea (Camellia sinensis) flowers

81%
Sun L., Wang Y., Ding Z., Liu F.
Acta Physiologiae Plantarum
|
2019
|
tom 41
|
nr 02
4

Ship maneuvering prediction using grey box framwork via adaptive RM-SVM with minor rudder

81%
Mei B., Sun L., Shi G., Liu X.
Polish Maritime Research
|
2019
|
tom 26
|
nr 3
A grey box framework is applied to model ship maneuvering by using a reference model (RM) and a support vector machine (SVM) (RM-SVM). First, the nonlinear characteristics of the target ship are determined using the RM and the similarity rule. Then, the linear SVM adaptively fits the errors between acceleration variables of RM and target ship. Finally, the accelerations of the target ship are predicted using RM and linear SVM. The parameters of the RM are known and conveniently acquired, thus avoiding the modeling process. The SVM has the advantages of fast training, quick simulation, and no overfitting. Testing and validation are conducted using the ship model test data. The test case reveals the practicability of the RF-SVM based modeling method, while the validation cases confirm the generalization ability of the grey box framework
5

Estimating evapotranspiration and Its components in cotton fields under deficit irrigation conditions

81%
Wu N., Yang C., Luo Y., Sun L.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 1
Estimating field crop evapotranspiration (ETc) along with its components of soil evaporation and crop transpiration is crucial for developing effective agricultural water-saving strategies. This study separately estimated ETc and its components in cotton fields using a SIMDualKc dual crop coefficient model. Data from a 2-year experiment (2010-2011) were used for model calibration and validation analysis. The experimental plots were irrigated at 1.00, 0.85, 0.70, 0.55, and 0.45 of full irrigation amount in north Xinjiang, China. Based on the results, SIMDualKc accurately estimated actual evapotranspiration (ETc adj) and its components under deficit drip irrigation conditions. Cotton field transpiration accounted for 85.4-94.3% of the ETc in the study area. Although plastic film significantly limited evaporative water loss, the fraction of water loss was still 5.7-14.6% of irrigation water. The adopted estimation method could lead to better understanding of where and when water loss occurs and how much water should be used for maximal benefit. A better understanding of these factors is critical for sustainable agricultural water management practices.
6

Scent marking behaviour in the male Chinese water deer

81%
Sun L., Xiao B., Dai N.
Acta Theriologica
|
1994
|
tom 39
|
nr 2
Two types of scent marking behaviour are described in male Chinese water deer Hydropotes inerrnis Swinhoe, 1870 in their natural habitat in Jiangxi, China. Of all marking events, forehead-rubbing accounted for 13.6%, and urination with defaecation and/or pawing with the forefeet accounted for 86.4%. Urine was the most frequently used marking material. During the mating season, bucks seemed to reduce the size of each pellet group to increase marking frequency. A higher proportion of pellet groups was deposited together in the mating season than the non-mating season. Marking occurred more frequently near the borders than on the inner areas of territories.
7

Human health risk assessment of organophosphate esters in urban topsoils of Shenyang, China

71%
Luo Q., Gu L., Shan Y., Wang H., Sun L.
Polish Journal of Environmental Studies
|
2020
|
tom 29
|
nr 4
8

Phytoextraction potential of Solanum nigrum L. and Beta vulgaris L. var. cicla L. in Cd-contaminated water

71%
Li Y., Hu X., Song X., Hou Y., Sun L.
Polish Journal of Environmental Studies
|
2015
|
tom 24
|
nr 4
The potential of two Cd-hyperaccumulators, Solarium nigrum L. (SN) and Beta vulgaris L. var. cicla L. (BV), as phytoremediation plants to remove Cadmium (Cd) from contaminated water was evaluated in hydroponics. The results showed that Cd exposure induced chlorosis and inhibited biomass growth in SN. However, these symptoms did not appear in BV. In BV, the Cd concentrations increased from 14.2 to 314.7 mg kg⁻¹ in the shoots and 241.1 to 4547.9 mg kg⁻¹ in the roots when the Cd concentration in the nutrient solution increased from 0.5 to 50 µМ. The corresponding increase in SN was from 7.4 to 100.6 mg kg⁻¹ in the shoots and 30.2 to 2010.7 mg kg⁻¹ in the roots. Generally, ВV showed a higher tolerance and accumulation of Cd, while SN was more efficient for Cd removal due to its higher biomass.
9

Influence of dissolved organic matter on Cd speciation in rhizosphere soil solution and phytoextraction by Sedum alfredii and Sedum sarmentosum

71%
Lian M., Zhang Y., Sun L., Hu X., Zeng X.
Polish Journal of Environmental Studies
|
2015
|
tom 24
|
nr 5
10
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Provenance-specific climate sensitivity of Pinus massoniana – a multi-environmental trial in subtropical China

71%
Zhang Z., Jin G., Feng Z., Sun L., Zhou Z.
Dendrobiology
|
2021
|
tom 85
11

Effects of sewage sludge biochar on soil characteristics and crop yield in Loamy sand soil

71%
You L., Sun L., Liu X., Hu X., Xu Q.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 4
Biochar produced from sewage sludge could provide an important alternative to waste management practices while offering an opportunity to improve soil properties and reduce the risk of contamination from direct applications of sewage sludge soil amendments. We assessed the impacts of different rates of biochar application (20, 40, 60 t ha-1) to peanuts grown in a loamy sand soil in the North China Plain on composition of the soil microbial community, soil bulk density (BD), pH, total carbon (TC), total nitrogen (TN), C:N, available phosphorus (P), available potassium (K), dissolved organic carbon (DOC) and crop yield. We found that sewage sludge biochar application increased TC, TN, available K, and C:N, and decreased soil BD and pH and had variable effects on DOC. Amendment with biochar increased microbial biomass and the proportion of Gram-positive bacteria, Gram-negative bacteria, fungi and Actinomycetes, while it decreased the ratios of groups of bacteria. The highest crop yield was achieved under 40 t ha-1 of biochar. Our study suggests that the lower rates of sewage sludge biochar application could improve soil physicochemical properties and increase levels of soil microbes and crop yield; however, the highest rate may induce negative effects on microbe community composition.
12

Effects of mismatches and insertions on discrimination accuracy of nucleic acid probes

71%
Piao X., Sun L., Zhang T., Gan Y., Guan Y.
Acta Biochimica Polonica
|
2008
|
tom 55
|
nr 4
713-720
Effective discrimination of non-complementary nucleotides is an important factor to ensure the accuracy of hybridization-based nucleic acid analyses. The current study investigates the effects of the chemical nature, the positions, the numbers, and the cooperative behavior of mismatches as well as insertions on 20-mer and 30-mer duplexes. We observed the hybridization stability trend affected by mismatches: G:T ≈ G:G > G:A > A:A ≈ T:T > A:C ≈ T:C > C:C. The experimental data show that mismatches at the center of the oligonucleotide probes have a more profound destabilizing effect on the hybridization stability than those at either ends. Insertions also demonstrate a similar destabilizing effect as mismatches. These results provide useful information for designing DNA microarray nucleotide probes and for improving the discrimination accuracy of hybridization-based detections.
13

Effects of waterlogging stress on the physiological response and grain-filling characteristics of spring maize (Zea mays L.) under field conditions

71%
Tian L., Bi W., Liu X., Sun L., Li J.
Acta Physiologiae Plantarum
|
2019
|
tom 41
|
nr 05
A field experiment was implemented to discuss the effects of waterlogging and subsurface waterlogging stress on the grain yield, grain-filling characteristics, superoxide anion (O⋅−₂) content, hydrogen peroxide (H₂O₂) content, malondialdehyde (MDA) content, antioxidant enzyme activity, proline, soluble protein content and SPAD value of the spring maize (Zea mays L.) hybrids “Demeiya1” (DMY1) and “Keyu16” (KY16). The waterlogging and subsurface waterlogging treatments were conducted for different durations (3, 6, and 9 days and 5, 10, and 15 days, respectively) at the seedling (V3), jointing (V6), and tasseling (VT) stages. The results showed that the most significant effects of waterlogging and subsurface waterlogging stress occurred at the V3 stage, followed by the V6 stage and then VT stage. Waterlogging and subsurface waterlogging caused a decline in grain filling, which resulted in a decline in grain weight and ultimately caused an obvious decrease in yield. The content of O⋅−₂ and H₂O₂ as well as MDA increased with the prolongation of the duration of waterlogging and subsurface waterlogging, which caused an up-regulation of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities, as well as increased proline and soluble protein contents and decreased SPAD value. In addition, we also demonstrated that KY16 is more sensitive than DMY1 to waterlogging and subsurface waterlogging.
14

C-fos upregulates P-glycoprotein, contributing to the development of multidrug resistance in HEp-2 laryngeal cancer cells with VCR-induced resistance

61%
Li G., Hu X., Sun L., Li X., Li J., Li T.
Cellular and Molecular Biology Letters
|
2018
|
tom 23
Background: Laryngeal cancer tends to have a very poor prognosis due to the unsatisfactory efficacy of chemotherapy for this cancer. Multidrug resistance (MDR) is the main cause of chemotherapy failure. The proto-oncogene c-fos has been shown to be involved in the development of MDR in several tumor types, but few studies have evaluated the relationship between c-fos and MDR in laryngeal cancer. We investigated the role of c-fos in MDR development in laryngeal cancer cells (cell line: human epithelial type 2, HEp-2) using the chemotherapeutic vincristine (VCR). Methods: HEp-2/VCR drug resistance was established by selection against an increasing drug concentration gradient. The expressions of c-fos and multidrug resistance 1 (mdr1) were measured using qPCR and western blot. C-fos overexpression or knockdown was performed in various cells. The intracellular rhodamine-123 (Rh-123) accumulation assay was used to detect the transport capacity of P-glycoprotein (P-gp, which is encoded by the mdr1 gene). Results: HEp-2 cells with VCR-induced resistance (HEp-2/VCR cells) were not only resistant to VCR but also evolved cross-resistance to other chemotherapeutic drugs. The expressions of the c-fos and mdr1genes were significantly higher in the HEp-2/ VCR cells than in control cells. C-fos overexpression in HEp-2 cells (c-fos WT) resulted in increased P-gp expression and increased the IC50 for 5-FU. C-fos knockdown in the HEp-2/VCR cells (c-fos shRNA) resulted in decreased P-gp expression and decreased IC50 for 5-FU. An intracellular Rh-123 accumulation assay showed that the mean intracellular fluorescence intensity (MFI) was lower in the HEp-2/VCR cells than in HEp-2 cells. C-fos WT cells also showed lower MFI. By contrast, c-fos shRNA cells exhibited a higher MFI than the control group. Conclusion: C-fos increased the expression of P-gp and mdr1 in the HEp-2/VCR cells, and enhanced the efflux function of the cells, thereby contributing to the development of MDR.
15

Association between RBMS1 gene rs7593730 and BCAR1 gene rs7202877 and Type 2 Diabetes Mellitus in a Chinese Han Population

61%
Kozakova O. V., Chen M., Jamaspishvili E., Lin Z., Yu J., Sun L., Qiao H.
Acta Biochimica Polonica
|
2018
|
tom 65
|
nr 3
16

Erratum to: from green to red: large-scale transcriptome comparison of a bud sport in poplar (Populus deltoides)

61%
Zhang F., Zhao J., Wan X., Luo X., Li W., Sun L., Chen Q.
Acta Physiologiae Plantarum
|
2017
|
tom 39
|
nr 04
17
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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LBP gene methylation involved in mRNA expression and resistance to E. coli F18 in weaned piglets

61%
Gan L. N., Bao W. B., Wu S. L., Qin W. Y., Sun L., Zhao C. X.
Polish Journal of Veterinary Sciences
|
2017
|
tom 20
|
nr 4
18

Model to assess the habitat suitability for endangered bird species: Brown Eared-pheasant Crossoptilon mantchuricum Swinhoe in Xiaowutaishan Reserve, China

61%
Li D., Gao S., Wu Y., Sun L., Guo S., Li J.
Polish Journal of Ecology
|
2008
|
tom 56
|
nr 4
723-729
Brown Eared-pheasant (Crossoptilon mantchuricum Swinhoe, 1863) is an endangered species endemic to China. Habitat management for Brown Eared-pheasant has to compensate the loss of natural forests and to improve their habitat quality. In this study, we applied a Habitat Suitability Index (HSI) model to analyze the habitat suitability and quality for the breeding populations of this species in Xiaowutaishan National Nature Reserve, North China. The Reserve (area 21833 ha) is located at 800–2882 m a.s.l. and high mountain and deep valley habitats as well as different types of mountain forest and alpine meadows occur there. We used six variables (vegetation type, canopy cover, altitude, exposure, slope gradient and position of slope) both in field observation and in the analysed model. According to the utilization rates of different habitat types by Brown Eared-pheasants, these variables were categorized into five classes (unsuitable, less suitable, moderately suitable, suitable, and highly suitable). Our results show that highly suitable, suitable, less suitable and unsuitable habitat accounted for 13.5%, 53%, 32%, and 1.5% of the entire reserve area, respectively. Our HSI model is well validated by the observed data. We expect this study can be useful as an example of successful model applying to the habitat management or population manipulation of the endangered species.
19

From green to red: large-scale transcriptome comparison of a bud sport in poplar (Populus deltoides)

61%
Zhang F., Zhao J., Wan X., Luo X., Li W., Sun L., Chen Q.
Acta Physiologiae Plantarum
|
2016
|
tom 38
|
nr 10
20

Physiological and antioxidant responses of Basella alba to NaCl or Na2 SO4 stress

52%
Ning J., Ai S., Yang S., Cui L., Chen Y., Sun L., Wang R., Li M., Zeng Z.
Acta Physiologiae Plantarum
|
2015
|
tom 37
|
nr 07
Salinity is a major factor negatively affecting plant growth and agricultural productivity. To gain a better insight into Basella alba responses to different salt stress, some physiological parameters were investigated on this species after 15-day exposure to 200 mM NaCl or 100 mM Na2SO4 stress. Plant growth was significantly suppressed under salinity and a more pronounced impairment induced by NaCl instead of Na2SO4 was observed. A high level of water content was maintained in salt-treated shoot. Salinity stress caused marked increase in Na+, Ca2+, Cl- and SO4 2- concentrations and decrease in K+ level and K+/Na+, Ca2+/Na+ and Mg2+/Na+ ratios in plants. The absorptive abilities of K+, Ca2+ and Mg2+ in plants were improved significantly under salinity. Plants suffered a deeper oxidative stress in the presence of NaCl than Na2SO4 as evidenced by the higher increase in foliar superoxide anions (O2-) and malondialdehyde (MDA) production as well as electrolyte leakage. No salt-induced alterations were observed on foliar hydrogen peroxide (H2O2) level. B. alba responded to the oxidative stress by enhancing antioxidant capacity involving ascorbate, reduced glutathione as well as antioxidant enzymes. Superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione reductase (GR) were all involved in the detoxification of reactive oxygen species (ROS) in plants exposed to salt stress, whereas catalase (CAT) only functioned in the Na2SO4-treated plants. The ability of water maintenance in shoot and improvement of cation absorbability as well as enhanced foliar antioxidant capability all contribute to the salt adaptation of B. alba, whereas a more efficient cation transport system and antioxidant mechanisms may be responsible for the better acclimation of this species to Na2SO4 than NaCl.
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