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Background: Phytoremediation is affected by physical and chemical properties of the soil such as soil pH, moisture, and nutrient content. Soil pH is a key element influencing Cd bioavailability and can be easily adjusted in agricultural practices. The soil pH level may relate to the effectiveness of phytoremediation; however, this has not been extensively investigated. In the current study, we evaluated the effect of Cd contamination level (0.56 and 0.92 mg/kg) and soil pH (5, 6, and 7) on Cd accumulation and allocation in Artemisia argyi, a fast-growing perennial crop. Results: Our results indicated that higher soil Cd concentrations reduce A. argyi biomass, and the loss of the root mass was particularly significant. Higher soil pH decreased Cd content in stems and roots of A. argyi cultivated in moderately Cd-polluted soil, and increased Cd content in stems and roots of the plant grown in low Cd-polluted soil. Higher soil pH decreased the percentage of Cd distributed in the soluble fraction and cell walls and increased the percentage of Cd in the organelles of leaf cells for moderate soil Cd levels. The bioconcentration and translocation factor exceeded 4.0 and 1.0, respectively, across all tested treatments, indicating that A. argyi is a promising candidate for phytoremediation. Notably, the effects of soil pH on Cd accumulation and subcellular distribution in A. argyi differed between low and moderately Cd-contaminated soils. Conclusion: Adjustments to soil pH based on the degree of Cd contamination can enhance Cd extraction by A. argyi, thereby reducing the overall remediation cycle of cadmium-polluted paddy fields of South China. [ABSTRACT FROM AUTHOR]

Riparian vegetation is crucial for maintaining terrestrial and aquatic biodiversity, but it is threatened by land-use activities. To assess the ecological impacts of riparian vegetation conversion to an oil tea (Camellia oleifera) plantation, we quantified the responses of small mammals in two natural habitats (mature forest and flood-meadow) and in Camellia forests at the community, population, and individual level. We found that the community diversity was similar between Camellia forests and mature forests, but higher than the flood-meadow. Meanwhile, the community composition differed across three habitats, with Camellia forests favoring habitat generalist species. At the population level, Camellia forests and flood-meadow had a similar population density, which were higher than mature forests. At the individual level, Rattus nitidus was less sensitive to this conversion, but the body condition index of Niviventer confucianus was higher in Camellia forests than in mature forests, and Apodemus agrarius in Camellia forests had more ectoparasite load than in the flood-meadow, indicating a species-specific response to the impacts of oil tea plantation. Our study highlights that the occurrence of habitat generalist species and high ectoparasite loads may threaten regional biodiversity and increase the risk of parasite transmission with enlarging the oil tea plantation area within riparian zones. [ABSTRACT FROM AUTHOR]

Cytochrome b (cyt b) gene complete sequences (1143bp) of Takydromus sylvaticus were sequenced. In order to clarify the phylogenetic position of the Takydromus sylvaticus, we investigated the phylogeny of 15 Takydromus spp. distributed in East-Asia by Maximum Parsimony (MP), Bayesian Inference (BI), and Maximum Likelihood (ML) methods using DNA fragments of cyt b genes. The results supported that the Platyplacopus merged into Takydromus and negated the validity of Platyplacopus. Furthermore, the prediction of tertiary structures of cyt b exhibited the CD loop region contain two short helices forming a hairpin arrangement, namely cd1 and cd2. Thermostability analysis shows that the CD-loop region is unstable thermodynamically and may provide mobility to amino acids located at the heme, and might provide high flexibility to the top of ISP (iron-sulfur protein) and the cavity region of Qo binding site. It suggested that the two short helices of CD loop region of cyt b was a dominating portion for ISP binding site.

Author(s): Ying Yu [1]; Jinjin Fan [1]; Xin-Sheng Chen [1, 5]; Dairong Wang [1]; Andres J Klein-Szanto [2]; Robert L Campbell [3]; Garret A FitzGerald [1]; Colin D Funk (corresponding [...]

Targeted disruption of 5-lipoxygenase gene by homologous recombination in embryonic stem cells establishes the physiological importance of leukotrienes, a class of biological mediators of inflammation and anaphylaxis. The observed 5-lipoxygenase-deficient mice show resistance to the harmful effects of endotoxin shock induced by the platelet-activating factor and confirm that leukotrienes are vital to the pathophysiology of specific inflammatory states. Mast cells release chemotactic leukotrienes that facilitate neutrophil recruitment during early inflammatory insult.

Species with mixed mating systems often demonstrate variable expression of breeding system characteristics and thus represent the opportunity to understand the factors and mechanisms that promote both outcrossed and selfed seed production. Here, we investigate variation in levels of herkogamy (variation in stigma-anther separation distance) in a Puerto Rican population of hummingbird pollinated Gesneria citrina Urban. There is significant variation in herkogamy levels among individuals of this species and stigma-anther separation is negatively associated with the ability to set fruits and seeds in the absence of pollinators. The variation in levels of herkogamy may represent a mechanism to ensure the production of some self-fertilized progeny in the absence of hummingbird pollinators. We also describe a novel breeding system in G. citrina, where stamens elongate over time to reach stigma height, but stamen elongation is accelerated by pollination. These results suggest that once the flowers are pollinated, stamen elongation may favor increased pollen removal and siring success, while the reduction in stigma-anther distance no longer imposes the risk of interference between male and female functions. We discuss our findings of breeding system variation in the context of pollination system evolution in an island setting (Antillean islands). [ABSTRACT FROM AUTHOR]

Sediment accretion (burial) and nutrient enrichment may exert a synergistic influence on the growth and distribution of macrophytes in floodplain wetlands; however, this phenomenon has rarely been examined. In this study, we investigated the effects of sediment accretion and nutrient enrichment on the growth and vegetative propagation of Phalaris arundinacea within a Carex thunbergii stand (one P. arundinacea ramet within 25 C . thunbergii ramets) using a factorial sediment burial (0, 3, and 6 cm) and nutrient addition (low, medium, and high) experimental design. High sediment burial (6 cm) without nutrient addition decreased the aboveground and total biomass of C. thunbergii but did not affect P. arundinacea , indicating that P. arundinacea is more tolerant to sediment burial than C. thunbergii . Moderate sediment burial (3 cm) with nutrient addition enhanced the aboveground and total biomass of P. arundinacea but did not affect C. thunbergii , indicating that P. arundinacea may gain a growth advantage over C. thunbergii under moderate sedimentation. High sediment burial with nutrient addition increased the number of rhizomes and ramets produced by P. arundinacea but did not affect C. thunbergii , indicating that the relative abundance of P. arundinacea may increase within the Carex community under high sedimentation conditions. Based on these results, it can be concluded that an increased sedimentation rate facilitates the invasion of P. arundinacea into Carex grasslands, and this invasion is further enhanced by nutrient enrichment. Therefore, management measures should be taken to reduce the sediment load and nutrient input to prevent Carex grasslands invasion by P. arundinacea and maintain the ecological function of floodplain wetlands., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision. The reviewer ZD declared a past co-authorship with the author X-SC to the handling editor., (Copyright © 2024 Guo, Zhong, Sun, Song, Liu and Chen.)

Aim: To study the effect of 5-lipoxygenase inhibitors on the expression of intercellular adhesion molecule-1 (ICAM-1) in melanoma cells., Methods: ICAM-1 protein of human melanoma cell a375 was detected by enzyme-linked immunosorbent, flow cytometry and Western blot analysis. Level of ICAM-1 mRNA in a375 was evaluated by Northern blot analysis. Adhesion of a375 to endothelial cell EC304 was analyzed by isotopic tracing., Results: 5-Lipoxygenase inhibitors nordihydroguaiaretic acid, AA861 and MK886, could suppress the expression of ICAM-1 protein as well as of its mRNA in a375 cells and reduce the adhesion of a375 to EC304., Conclusion: 5-Lipoxygenase inhibitors can inhibit the expression of ICAM-1 in human melanoma cells and may be valuable for treatment of melanoma metastasis.