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Background:  miR-125a-5p regulated biological processes in various types of cancer, including colorectal cancer (CRC). TAZ, a vital transcriptional coactivators of the Hippo pathway, was found to be overexpressed in various cancers. Objectives: This study aims to study the effect of miR-125a-5p on the progression of CRC by regulating TAZ expression. Methods:  In this study, miR-125a-5p and TAZ expression in CRC tissue and cell lines were detected by real-time polymerase chain reaction (RT-PCR). Luciferase reporter assay was applied to detect whether TAZ was a target of miR-125a-5p. Cell migration and invasion were detected in vitro by wound-healing assay and cell invasion assay. Western blot was used to detect the expression of epithelial-mesenchymal transition (EMT)-related proteins. Findings: The results revealed downregulation of miR-125a-5p, as well as upregulation of TAZ in CRC tissue and cell lines. TAZ was identified as a direct target of miR-125a-5p, and its expression was negatively regulated by miR-125a-5p in CRC cell lines. The functional studies revealed that overexpression of miR-125a-5p inhibited the migration, invasion and EMT of CRC cells, while upregulation of TAZ reversed the inhibitory effect caused by miR-125a-5p. Conclusion: Our data suggest that miR-125a-5p inhibits CRC cell migration, invasion and EMT by targeting TAZ. These results suggest that miR-125a-5p serves as a potential therapeutic biomarker for CRC patients. [ABSTRACT FROM AUTHOR]

A bamboo species (Phyllostachys praecox) and a Cd/Zn hyperaccumulator (Sedum plumbizincicola) were tested under different planting systems to compare their heavy metal phytoremediation ability. P. praecox (MP), S. plumbizincicola (MS) and P. praecox × S. plumbizincicola (IPS) plantations were established in Cu, Zn, and Cd-contaminated soil. Soil properties and heavy metal contents in plants were determined and compared after four years of plantation establishment. The rankings of available and total metal contents in soil layers were MP > MS > IPS (0-20 cm) and MP > IPS > MS (20-40 cm, except for Cu), respectively. The Cu and Zn contents in mature bamboo tissues were significantly lower, but the Cd contents in bamboo tissues (except for leaves) higher, in the IPS than in the MP. The bioconcentration and the translocation factors in most of bamboo tissues showed an increasing trend from the MP to the IPS. Heavy metal distribution in plants is greatly affected by the planting patterns. The tested intercropping system of two plant species showed higher biomass productivity, implying more heavy metals can be removed from the soil through the harvesting of plants. Therefore, the IPS leads to significant improvement of soil phytoremediation. [ABSTRACT FROM AUTHOR]

Evidence has suggested that salidroside inhibits the proliferation and invasion of renal clear cell, lung, breast, and colon cancer. However, effect of salidroside on colorectal cancer (CRC) cells against oxaliplatin (L-OHP) resistance remains unclear. In the present study, the CRC HT-29 cell line and L-OHP resistance HT-29/L-OHP cell line were used to evaluate the effect, and mechanism of salidroside on L-OHP resistance. The results demonstrated that the activity of HT-29 cells was lower compared with that of HT-29/L-OHP cells following L-OHP intervention, and was accompanied with varied expression levels of drug resistant proteins. The combination of salidroside and L-OHP weakened cell activity significantly compared single utilization. Compared with the control group, salidroside intervention resulted in a higher percentage of HT-29/L-OHP cells in the G0/G1 stage, and reduced percentage in the G2/M stage, but no significant variation in the S stage. The HT-29/L-OHP cells exhibited increased apoptosis rates and caspase-3 activity, but decreased metastatic, and invasive abilities following salidroside intervention. Quantitative polymerase chain reaction and western blot analysis detected variations in the expression levels of associated genes in HT-29/L-OHP cells following salidroside intervention. In all, the results of the present study revealed that salidroside is able to decrease the activity and invasive capacity of HT-29/L-OHP cells, and treatment with salidroside is associated with increased apoptosis of cancer cells through the regulation of certain genes. [ABSTRACT FROM AUTHOR]

Purpose: The sources of and changes in molecular composition of soil organic carbon (SOC) due to land use change in a paddy soil chronosequence ˃6000 years old were studied using a lipid biomarker approach. Materials and methods: Lipid biomarkers comprising fatty acids, aliphatic alcohols, and sterols were used to evaluate rice field reclamation and management over 6000 years on sources of and changes in molecular composition of SOC in two soil profiles comprising of the following three soil chronosequence layers (from bottom to top): 6280-year-old BP prehistoric paddy soil/pristine upland, 3320-year-old BP ancient paddy soil, and the present paddy soil. Furthermore, comparison with adjacent abandoned paddy soils was made to indicate the effect of abandoning cultivation due to urbanization on the sources and fluctuations in the molecular composition of SOC. Results and discussion: Fatty acids and aliphatic alcohols represented the most abundant fraction (∼80%) of autochthonous organic carbon sources from microbial activity in the prehistoric pristine upland. Reclamation of pristine upland to submerged rice fields led to 44.5 and 41.1% increases in the ratio of long-chain n-fatty acids and n-alcohols (≥C22), respectively, to the total saturated homologs indicating an increased input of allochthonous organic matter sources derived from rice cropping. The evolution of the paddy soil from 6280 to 3320 years BP and then to the present was accompanied by a slight and gradual increase in the proportion of the higher plant-derived organic components. Abandonment of rice cropping led to an apparent decrease in the concentration of the lipid biomarkers suggesting a decline in rice roots and stubble inputs and of microbial activity. Conclusions: Lipid biomarkers can be used to trace the sources and fluctuations in the molecular composition of SOC in paddies owing to land use change. Fatty acids were more suitable as the lipid proxy than aliphatic alcohols or sterols. [ABSTRACT FROM AUTHOR]

Rice cultivation requires large quantities of irrigation water and mineral fertilizers. This provides an opportunity for the recycling of the plant nutrients in anaerobically digested pig slurry, large amounts of which are generated in Chinese pig farms. Hence, to promote the sustainable development of livestock and poultry breeding and rice production, a micro-plot field experiment was carried out to assess whether or not slurry can replace mineral fertilizers in rice paddy production in terms of plant tillering, grain quality, and yields. The results indicate that the total N content of the slurry can serve as an alternative source of N when compared to the control (450 kg ha commercial compound fertilizer (N/PO/KO = 15:15:15) as basal fertilizer, 300 kg ha urea (N% = 46), and 150 kg ha commercial compound fertilizer as top-dressed fertilizer). No negative effects on plant growth or grain yield were observed, although there may be a potential risk due to an increase in grain Cu concentration. The amylose content and gel consistency of the rice grains were enhanced significantly by the use of slurry as a basal fertilizer, but the grain protein and total amino acid contents decreased. The results suggest that anaerobically digested pig slurry can replace mineral fertilizers in rice production when applied as a basal dressing together with urea and commercial compound fertilizer as top-dressed fertilizers. [ABSTRACT FROM AUTHOR]

The influence from the manufacturing of compact fluorescent lamps (CFL) on mercury (Hg) speciation and distribution in river catchments nearby a typical CFL manufacturing area in China was investigated. Water, sediment, river snail ( Procambarus clarkii), and macrophyte ( Paspalum distichum L.) samples were collected. Total Hg (THg) and methylmercury (MeHg) concentrations in water ranged from 1.06 to 268 ng · L and N.D. −2.14 ng · L, respectively. MeHg was significantly positively correlated with THg in water. THg and MeHg in sediment ranged from 15.0 to 2480 and 0.06 to 1.85 ng · g, respectively. River snail samples exhibited high concentrations of THg (206-1437 ng · g) and MeHg (31.4-404 ng · g). THg and MeHg concentrations in root of P. distichum L. were significantly higher than those in shoot, indicating that THg and MeHg in the plant were mainly attributed to root assimilation. A very high bioaccumulation factor (20.9 ± 22.1) for MeHg in P. distichum L was noted, suggesting that P. distichum L. might have a potential role in phytoremediating MeHg contaminated soil due to its abnormal uptake capacity to MeHg. [ABSTRACT FROM AUTHOR]

An arsenic hyperaccumulator,Pteris vittataL., is common in nature and could occur either on As-contaminated soils or on uncontaminated soils. However, it is not clear whether phosphate transporter play similar roles in As uptake and translocation in nonmetallicolous and metallicolous populations ofP. vittata. Five populations were used to investigate effects of phosphate on arsenate uptake and translocation in the plants growing in 1.2 L 20% modified Hoagland's nutrient solution containing either 100 μM phosphate or no phosphate and 10 μM arsenate for 1, 2, 6, 12, 24 h, respectively. The results showed that the nonmetallicolous populations accumulated apparently more As in their fronds and roots than the metallicolous populations at both P supply levels. Phosphate significantly (P < 0.01) decreased frond and root concentrations of As during short time solution culture. In addition, the effects of phosphate on As translocation inP. vittatavaried among different time-points during time-course hydroponics (1–24 h). The present results indicated that the inhibitory effect of phosphate on arsenate uptake was larger in the three nonmetallicolous populations than those in the two metallicolous populations ofP. vittata. [ABSTRACT FROM AUTHOR]

Although it is known that the first As hyperaccumulator identified, Pteris vittata L., could exist in As-contaminated as well as uncontaminated soils, intra-specific variation in As accumulation among metallicolous (from As-contaminated soils) and nonmetallicolous populations (from uncontaminated soils) of P. vittata has not been fully explored. Variations in As concentrations of fronds were observed in three nonmetallicolous populations and four metallicolous populations of P. vittata collected from southeast China. The kinetics study showed that the concentration-dependent influx of arsenate and arsenite observed followed Michaelis-Menten kinetics, and that the average V for arsenate and arsenite was apparently larger in the three nonmetallicolous populations than that in the three metallicolous populations. The pot trials indicated that the nonmetallicolous populations had significantly ( p < 0.05) higher frond biomass, about 1.5-1.9-folds, when compared with the metallicolous populations in 250 and 500 mg As kg soil treatments. The pot trials also demonstrated that the nonmetallicolous population of P. vittata had a significantly higher accumulation and translocation capacity for As. The present study suggests that As removal by P. vittata can be greatly enhanced by the judicious selection of the appropriate populations. [ABSTRACT FROM AUTHOR]

A pot trial was conducted to investigate the effects of three arbuscular mycorrhizal (AM) fungi species, including Glomus geosporum BGC HUN02C, G. versiforme BGC GD01B, and G. mosseae BGC GD01A, on grain yield and arsenic (As) uptake of upland rice (Zhonghan 221) in As-spiked soils. Moderate levels of AM colonization (24.1-63.1 %) were recorded in the roots of upland rice, and up to 70 mg kg As in soils did not seem to inhibit mycorrhizal colonization. Positive mycorrhizal growth effects in grain, husk, straw, and root of the upland rice, especially under high level (70 mg kg) of As in soils, were apparent. Although the effects varied among species of AM fungi, inoculation of AM fungi apparently enhanced grain yield of upland rice without increasing grain As concentrations in As-spiked soils, indicating that AM fungi could alleviate adverse effects on the upland rice caused by As in soils. The present results also show that mycorrhizal inoculation significantly ( p < 0.05) decreased As concentrations in husk, straw, and root in soils added with 70 mg kg As. The present results suggest that AM fungi are able to mitigate the adverse effects with enhancing rice production when growing in As-contaminated soils. [ABSTRACT FROM AUTHOR]

We assessed the effect of mycorrhizal inoculation on short-term uptake kinetics of arsenate and arsenite by excised roots of upland rice ( Oryza sativa L. cv. Zhonghan 221). A concentration of 0.01-0.05 mM arsenic (As) differentially affected the influx rates of both arsenate and arsenite into rice roots non-inoculated or inoculated with Glomus mosseae and G. versiforme. While Vmax for arsenate uptake by non-mycorrhizal roots was 1.02 µmol g−1 fresh weight h−1, it was reduced by a factor of 2.4 for mycorrhizal roots (about 0.42 µmol g−1 fresh weight h−1) in the high-affinity uptake system. However, at high concentrations of 0.5-2.5 mM As only G. versiforme was able to reduce As influx. The results show that mycorrhizal effects on As uptake of upland rice are both concentration and species-specific. [ABSTRACT FROM AUTHOR]

Iris pseudacorusL. (yellow flag) is a wide-use wetland plant for constructed wetlands for removing metals from wastewater. This study aims to understand effects of root iron plaque on sequestration and translocation of Cr and Ni in yellow flag seedlings using a hydroponic experiment. Yellow flag seedlings (4-week-old seedlings with 4–6 leaves) with or without iron plaque induction (at 50 mg Fe2+L−1for 72 hours) were spiked for 6 days in the Hoagland solution with Cr or Ni at 0.5, 5, and 50 mg L−1, equivalent to 1, 10, 100 times of thresholds of surface water quality, respectively. Results indicated that root iron plaque significantly reduced translocation of Cr and Ni to root but increased from root to shoot. Root iron plaque formation counteracted Cr toxicity to yellow flag seedlings while the control showed Cr toxicity to root at 5 mg L−1and to shoot at 50 mg L−1with significant biomass loss. Neither Ni exposures caused significant biomass loss nor root iron plaque formation significantly changed Ni distribution among plant parts. Our study suggests that root iron plaque effects on metal sequestration and translocation in yellow flag seedlings were metal-dependent. [ABSTRACT FROM AUTHOR]

In order to investigate the effects of soil microorganisms on biochemical and physiological response of plants to PAHs, PAH-degrading bacteria(Acinetobacter sp.)and/or arbuscular mycorrhizal fungus(Glomus mosseae)were inoculated with ryegrass(Lolium multiflorum)under four different concentrations of phenanthrene and pyrene (0, 50 + 50, 100 + 100, 200 + 200 mg kg–1) in soils.Acinetobacter sp.played limited roles on the growth of ryegrass, chlorophyll content, water soluble carbohydrate content, malondialdehyde (MDA) content, activities of superoxide dismutase (SOD) and peroxidase (POD) in shoot. By contrast,G. mosseaesignificantly (P < 0.01) increased ryegrass growth, partially by improving the photosynthetic activity through increasing the chlorophyll content in shoot.G. mosseaealso significantly decreased MDA content in shoot. However,G. mosseaesignificantly increased SOD activity in shoot, which seemed to be resulted from significantly higher pyrene concentrations in shoot. The present study suggested that AM fungi could reduce the damage of cell membranes caused by free radicals, which may be one of the mechanisms involved in mycorrhizal alleviation of plant stress under PAHs. The present study indicated that the dual inoculation was superior to single inoculation in remediating PAHs contaminated soils. Supplemental materials are available for this article. Go to the publisher's online edition ofInternational Journal of Phytoremediationto view the supplemental file. [ABSTRACT FROM AUTHOR]