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Effects of physiological integration and phosphorus on spread of Alternanthera philoxeroides from soil to chromium-contaminated aquatic habitats

100%

Xu L., Wu X.

Polish Journal of Ecology

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2018

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tom 66

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nr 4

Aquatic ecosystems are receivers for various pollutants, for instance, Chromium (Cr, one of the toxic heavy metals) and phosphorus (one of the biggest causes of water eutrophication). Such contaminants have brought serious impact on health and security of aquatic ecosystems. Physiological integration between the integrated ramets of clonal plants can increase their tolerance to environmental stress. It is hypothesized that physiological integration and phosphorus could facilitate the expansion of amphibious clonal plants from soil to Cr-polluted aquatic habitats. This study was conducted to primarily examine how physiological integration and phosphorus affected the effects of Cr on plant growth and population expansion. An amphibious clonal herbaceous plant Alternanthera philoxeroides was used to simulate the spread process by induced stolon connection or disconnection, Cr pollution and different levels of phosphorus in aquatic habitats. We found that Cr pollution deployed to apical ramets directly decreased the growth and photosynthetic parameters of the apical ramets that lacked connections to the basal ramets, but these effects could be mitigated by stolon connections. Cr pollution had no effects on these disconnected basal ramets, but the transmission of Cr from the apical parts via connected stolons negatively affected the growth of the basal ramets. Increasing the phosphorus not only increased the growth but also decreased the levels of Cr that accumulated in the plant tissues and the bioactivity of Cr. These results indicated that increasing the phosphorus could benefit the population expansion and establishment of A. philoxeroides through physiological integration from terrestrial to Cr-polluted aquatic habitats.

2

Decomposition of plant litter under chromium pollution and associated characteristics of chromium release

100%

Xu L., Wu X.

Polish Journal of Environmental Studies

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2019

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tom 28

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nr 4

In vegetated constructed wetlands, plants used for phytoremediation may release pollutants back into the aquatic system as a result of decomposition after senescence, lessening wastewater disposal efficiency. After treatment of wastewater containing chromium with Alternanthera philoxeroides in constructed wetland, plant litter was used to study the release characteristics of chromium with the biomass decomposition under different levels of Cr pollution. Results indicate that decomposition rates of plant litter under zero and low-level Cr pollution were larger than those under high pollution concentration. Under low Cr intensity, the total Cr concentration in the residual increased in the first 40 days, and then decreased to 67.72% of the initial concentration. In the end, the residual ratios of plant litter in different pollution intensities were 57.91%, 48.16% and 71.79% of the initial mass on average separately, and about 57.45%, 67.14% and 38.32% of Cr had been released into the aquatic environment. The changes in percentages of chemical forms in residual should be correlated with the decomposition process reflected by the interactive effects. The release of Cr could be divided into two stages, i.e. immobilization and discharge. These results were possible coming from the moderating effect of different Cr intensities on microbial decomposers.

3

Modulated human globin gene expression: role for antisense expression vectors

100%

Xu L., Pace B. S.

Cellular and Molecular Biology Letters

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1998

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tom 03

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nr 4

Several approaches have been explored to prevent polymerization of sickle hemoglobin in erythrocytes. We tested the ability of a mammalian expression vector carrying a β gene antisense cDNA fragment to block β gene expression. The antisense expression vector was stably transfected into HS2γβ stable mouse erythroleukemia cell lines producing human γ and β globin chains. By day 14 there was an average 24% decrease and 12% increase in β and γ globin mRNA levels respectively. We observed a loss of β gene inhibition by day 42. This study suggests that a β globin antisense cDNA expression vector may be an alternative gene therapy strategy to decrease sickle hemoglobin levels in patient with sickle cell disease.

4

Effects of physiological integration and fertilization on heavy metal remediation in soil by a clonal grass

81%

Xu L., Wu X., Zhou Z.-F.

Polish Journal of Environmental Studies

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2016

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tom 25

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nr 1

In this paper, ramets of an annual clonal grass Digitaria sanguinalis were subjected to rhizome severing and heavy metal pollution to determine the effects of physiological integration on growth and heavy metal accumulation traits. The negative effect of pollution on survival of offspring ramets was modified by the presence of a stolon connection. Generally, pollution negatively affected growth of offspring ramets and integrated parents. Offspring ramets in polluted soils and connected parents had higher metal contents than those outside polluted soils. In offspring, pollution and rhizome severing reduced the translocation factor (TF) of copper but pollution increased TF of zinc. The results implied that strengthened resource supply with physiological integration was likely to alleviate heavy metal stress to a greater extent. Therefore, connected clones were induced to three levels of fertilization and four heavy metal pollution treatments, studying to what extent fertilization benefited plants. The application of fertilizer to the parents slightly increased the survival rate of connected offspring. The clones produced more biomass with increasing fertilizer intensity. Fertilization resulted in less biomass allocation to roots, but the specific effect of heavy metal led to more investment to root. Fertilization promoted heavy metal accumulation and positively affected TF through integration. The suggested appropriate utilization of fertilizer in connected clones could compensate for damage induced by heavy metal to the whole system. This method should be of great potential use for remediation of heavy metals in soils by clonal plants.

5

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The Jiyuan tetrapod fauna of the Upper Permian of China: new pareiasaur material and the reestablishment of Honania complicidentata

81%

Xu L., Li X.-W., Jia S.-H., Liu J.

Acta Palaeontologica Polonica

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2015

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tom 60

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nr 3

Honania complicidentata and Tsiyuania simplicidentata are pareiasaur taxa based on material from the Shangshihezi Formation of Jiyuan, Henan Province, China that were earlier designated as nomina vana. Based on the study of new material, and the reexamination of old specimens, we determine that the pareiasaur material from Jiyuan represents a single species that differs from all known species from other localities. Thus, we resurrect the name H. complicidentata for the material from Jiyuan. H. complicidentata is characterized by maxillary teeth with high crowns, dentary teeth slightly posteriorly inclined compared to the dentary dorsal margin, nearly all preserved marginal teeth have a cusped cingulum on the lingual surface, and humerus without an ectepicondylar foramen. Phylogenetic analysis shows Honania is more basal than Shansisaurus and Shihtienfenia from the Sunjiagou Formation of China.

6

Length-frequency compositions and weight-length relations for big-eye tuna, yellowfin tuna, and albacore [Perciformes: Scombrinae] in the Atlantic, Indian, and eastern Pacific Oceans

81%

Zhu G., Xu L., Zhou Y., Dai X.

Acta Ichthyologica et Piscatoria

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2008

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tom 38

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nr 2

157-161

Background. Bigeye tuna, Thunnus obesus (Lowe, 1839); yellowfin tuna, Thunnus albacares (Bonnaterre, 1788); and albacore, Thunnus alalunga (Bonnaterre, 1788), are very important species for world fisheries. It is crucial to the future existence of those economically important species that the best possible biological data on the species is provided to fisheries managers. Materials and Methods. The weight–length relations (WLRs) for bigeye tuna, yellowfin tuna, and albacore, collected in the Atlantic, Indian, and eastern Pacific oceans were studied using commonly accepted methodology. Results. Significant differences can be found from the fork length distributions and the WLRs of the above 3 tuna species and the relations of gilled-gutted and whole weight of bigeye and yellowfin tunas collected from the Atlantic, Indian, and Eastern Pacific Oceans. Significant differences of fork length distributions can be found for bigeye tuna, yellowfin tuna, and albacore from the three areas. The growth exponents (b) of bigeye tuna, yellowfin tuna, and albacore collected from the Atlantic, Indian, and eastern Pacific oceans register significant deviations from isometric value of 3. Conclusion. The date collected will be useful for the fisheries management of the three species studied.

7

Amount and activity changes of 20S proteasome modified by oxidation in salt-treated wheat root tips

81%

Shi C., Zhang Y., Xu L., Bian K.

Acta Physiologiae Plantarum

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2011

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tom 33

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nr 4

To study the response of 20S proteasome in wheat (Triticum aestivum L.) roots to salt stress, the root tips from wheat seedlings treated with 200 mM NaCl for different times were used for studying its carbonyl level, caseinolytic activity, protein abundance and other biochemical characteristics. The contents of carbonylated and ubiquitinated proteins (Ub-P) were also investigated. During this stressed process, both the productive rate of O₂⁻ and the content of H₂O₂ gradually increased, with the concomitant increase in carbonyl level of total soluble proteins and 20S proteasome, together with the gradual increase in the activities of the total and 20S proteasome in salt-treated root tips. However, the amounts of 20S proteasome decreased particularly during this process. Moreover, metal-catalyzed oxidation of proteins from control plants in vitro validated that the oxidative modification also could increase the activity of 20S proteasome, but decrease its abundance. In addition, the amounts of Ub-P with molecular weights above 35 kDa remained similar to the control plants, but that below 35 kDa decreased significantly in treated root tips. The changes in the proteasome activity and amount argue in favor of the active involvement of this proteolytic system in salt-stressed plants.

8

Enterococcus faecalis bioflocculant enhances recovery of graphene oxide from water

81%

Xu L., Ma R., Sun C., Sun D.

Polish Journal of Environmental Studies

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2018

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tom 27

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nr 6

Bioflocculation is a promising method of removing GO from the water as it is safe, biodegradable, and non-secondary pollution, but few studies on effective and economic bioflocculant of GO have been reported. Accordingly, this work evaluated flocculation efficiency of an extracellular bioflocculant named MBF-21 produced by Enterococcus faecalis. Optimum culture conditions for bioflocculant production were initial medium pH of 7 and incubation temperature of 40ºC. The optimum carbon and nitrogen sources for bioflocculant production were glucose and beef extract. Results of Fourier transform infrared (FTIR) indicated the presence of carboxyl, hydroxyl, and amide groups on the MBF-21. The Zeta potential of MBF-21 analysis revealed that MBF-21 was mainly negatively charged. MBF-21 showed a significant ability in flocculation of GO, and flocculation efficiency was over 90% under neutral, acidic, and alkaline conditions, indicating that flocculation of GO was ion-independent. The conditions for flocculation of GO were optimized by response surface methodology (RSM) and determined to be an 11.57 mg/L dose and flocculation time of 75 min.

9

Studying soil salinity and its relations with microtopography and vegetation at field scale

71%

Zhao C.-W., Xu L., Wang Z.-C., Wang Y.-H., Chi C.-M.

Polish Journal of Environmental Studies

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2013

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tom 22

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nr 4

Spatial variation of soil salinity and sodicity is a typical characteristic of Songnen Plain grasslands in northeast China. Best management practices and grassland productivity improvement require further understanding of the relationships among the causal factors at field scale. A field soil survey for the interactions among salinity, microtopography, and vegetation was conducted on a 2.8 hectare saline sodic grassland at Da’an Sodic Land Experimental Station, Chinese Academy of Sciences, northeast China. Salinity of the soil decreases by depth increment with Na+ and HCO-3 as the dominant ions. Soil salinity and sodicity parameters measured include pH, electrical conductivity for 1 to 5 soil-water extracts (EC1:5), apparent electrical conductivity (ECa), sodium adsorption ratio, and exchangeable sodium percentage. Soil salinity is in an order of slope > mound > depression for microtopography and soil under S. corniculata community is in severe salinity, while there is no significant difference under P. australis-A. mongolica and P. australis communities. The water and salt regime in various microtopographical conditions also is discussed.

10

Antioxidant responses to waterlogging stress and subsequent recovery in two Kentucky bluegrass (Poa pratensis L.) cultivars

71%

Puyang X., An M., Xu L., Han L., Zhang X.

Acta Physiologiae Plantarum

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2015

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tom 37

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nr 10

The antioxidant enzyme activities and gene expressions in leaves of Kentucky bluegrass (Poa pratensis L.) were investigated in response to waterlogging stress and subsequent drainage. Two cultivars contrasting in waterlogging tolerance, ‘Moonlight’ (waterlogging-tolerant) and ‘Kenblue’ (waterlogging-sensitive), were subjected to waterlogging for 28 days (d) followed by 7 d of drainage recovery. Waterlogging stress increased malondialdehyde (MDA), superoxide anion (O2 -) and hydrogen peroxide (H2O2) in both cultivars. Moonlight exhibited greater turfgrass quality (TQ) rating and chlorophyll (Chl) content than Kenblue during the waterlogging and drainage period. After 7 d of drainage, all physiological parameters returned to the control level for Moonlight, but not for Kenblue. Higher activities of superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) as well as more abundance of isozymes were found in Moonlight relative to Kenblue under waterlogging stress. Moonlight showed higher SOD and APX activity and isozymes intensity when compared with Kenblue during the drainage period. The transcript levels of chloroplastic Cu/ZnSOD (Chl Cu/ZnSOD), MnSOD, FeSOD, POD and cytosolic APX (Cyt APX) were higher in Moonlight relative to Kenblue under waterlogging conditions, and higher transcript activities of Chl Cu/ZnSOD, FeSOD and Cyt APX were observed in Moonlight than in Kenblue at 7 d of drainage. The results of this study indicate that higher SOD and APX activity, isozymes intensity and gene expression level in Moonlight relative to Kenblue may play crucial roles in Kentucky bluegrass tolerance to waterlogging stress.

11

DNA vaccine encoding Haemonchus contortus Actin induces partial protection in Goats

71%

Yan R., Wang J., Xu L., Song X., Li X.

Acta Parasitologica

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2014

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tom 59

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nr 4

Actin is a globular multi-functional protein that forms microfilaments, and participates in many important cellular processes. Previous study found that Haemonchus contortus actin could be recognized by the serum of goats infected with the homology parasite. This indicated that H. contortus actin could be a potential candidate for vaccine. In this study, DNA vaccine encoding H. contortus actin was tested for protection against experimental H. contortus infections in goats. Fifteen goats were allocated into three trial groups. The animals of Actin group were vaccinated with the DNA vaccine on day 0 and 14, and challenged with 5000 infective H. contortus third stage larval (L3) on day 28. An unvaccinated positive control group was challenged with L3 at the same time. An unvaccinated negative control group was not challenged with L3. The results showed that DNA vaccine were transcribed at local injection sites and expressed in vivo post immunizations respectively. For goats in Actin vaccinated group, higher levels of serum IgG, serum IgA and mucosal IgA were produced, the percentages of CD4+ T lymphocytes, CD8+ T lymphocytes and B lymphocytes and the concentrations of TGF-β were increased significantly (P<0.05). Following L3 challenge, the mean eggs per gram feces (EPG) and worm burdens of Actin group were reduced by 34.4% and 33.1%, respectively. This study suggest that recombinant H. contortus Actin DNA vaccine induced partial immune response and has protective potential against goat haemonchosis.

12

Molecular cloning of enolase from Trichinella spiralis and the protective immunity in mice

71%

Zhang X., Xu L., Song X., Li X., Yan R.

Acta Parasitologica

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2018

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tom 63

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nr 2

13

Isolation and identification of Mycoplasma mycoides cluster strains from goats in Chongqing, China

71%

Wang H., Yang H., Xu L., Ma N., Ding H.

Bulletin of the Veterinary Institute in Puławy

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2014

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tom 58

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nr 1

In order to evaluate the prevalence of the Mycoplasma mvcoides cluster in goats in Chongqing, China, an epidemiological survey in this area was carried out. A total of 68 samples were subjected to bacteria isolation on Hartley's medium. Four isolates (three from lung tissue and one from nasal discharges) were recovered from the samples and identified as the Mycoplasma species by their morphological and biochemical characteristics. They were further confirmed by PCR using 16S rRNA specific primer pairs and by restriction enzyme analysis. In vitro antimicrobial susceptibility of the isolates indicated that some strains had developed resistance to the antibiotics tested. This is the first report on the isolation, identification, and molecular characterisation of Mycoplasma species isolated from goats in Chongqing. This study also revealed a prevalence of Mycoplasma species infection in goats in this area.

14

Leaf anatomy and cytology in field-grown 'blunt with blossom' cucumber

71%

Li Z. Y., Xu L., Yang G. D., Li X. G., Zheng C. C.

Vegetable Crops Research Bulletin

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2003

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tom 59

15

Effects of physiological integration and phosphorus on spread of Alternanthera philoxeroides from soil to chromium-contaminated aquatic habitats

Decomposition of plant litter under chromium pollution and associated characteristics of chromium release

Modulated human globin gene expression: role for antisense expression vectors

Effects of physiological integration and fertilization on heavy metal remediation in soil by a clonal grass

The Jiyuan tetrapod fauna of the Upper Permian of China: new pareiasaur material and the reestablishment of Honania complicidentata

Length-frequency compositions and weight-length relations for big-eye tuna, yellowfin tuna, and albacore [Perciformes: Scombrinae] in the Atlantic, Indian, and eastern Pacific Oceans

Amount and activity changes of 20S proteasome modified by oxidation in salt-treated wheat root tips

Enterococcus faecalis bioflocculant enhances recovery of graphene oxide from water

Studying soil salinity and its relations with microtopography and vegetation at field scale

Antioxidant responses to waterlogging stress and subsequent recovery in two Kentucky bluegrass (Poa pratensis L.) cultivars

DNA vaccine encoding Haemonchus contortus Actin induces partial protection in Goats

Molecular cloning of enolase from Trichinella spiralis and the protective immunity in mice

Isolation and identification of Mycoplasma mycoides cluster strains from goats in Chongqing, China

Leaf anatomy and cytology in field-grown 'blunt with blossom' cucumber

A numerical and experimental study of marine hydrogen-natural gas-diesel tri-fuel engines

Spatial distribution, risk assessment, and seasonal variations of 4-nonylphenol in China’s Yinma River Basin

Secretion of catalpol from Rehmannia glutinosa roots to the rhizosphere

Epigenetic control of Pollen Ole e 1 allergen and extensin family gene expression in Arabidopsis thaliana

Reconstruction of oviraptorid clutches illuminates their unique nesting biology

A new troodontid theropod from the Late Cretaceous of central China, and the radiation of Asian troodontids