Traditional and Novel Organophosphate Esters in Plastic Greenhouse: Occurrence, Multimedia Migration, and Exposure Risk via Vegetable Consumption.

The migration and risk of organophosphate esters (OPEs) in agricultural air-soil-plant multimedia systems due to plastic film application remain unclear. This study investigates the multimedia distribution of traditional OPEs (TOPEs), novel OPEs (NOPEs), and their transformation products (POPEs) in plastic and solar greenhouses. The total concentration of OPE-associated contaminants in air and airborne particles ranged from 594 to 1560 pg/m3 and 443 to 15600 ng/g, respectively. Significant correlations between air OPE concentrations and those in polyolefin film (P < 0.01) indicate plastic film as the primary source. Contaminants were also found in soils (96.8-9630 ng/g) and vegetables (197-7540 ng/g). The primary migration pathway for NOPEs was particle dry deposition onto the soil and leaf, followed by plant accumulation. Leaf absorption was the main uptake pathway for TOPEs and POPEs, influenced by vegetable specific leaf surface area. Moreover, total exposure to OPE-associated contaminants via vegetable intake was assessed at 2250 ng/kg bw/day for adults and 2900 ng/kg bw/day for children, with an acceptable hazard index. However, a high ecological risk was identified for NOPE compounds (median risk quotient, 975). This study provides the first evidence of the multimedia distribution and potential threat posed by OPE-associated contaminants in agricultural greenhouses.

Internalization, physiological responses and molecular mechanisms of lettuce to polystyrene microplastics of different sizes: Validation of simulated soilless culture.

Microplastics (MPs) exists widely in the environment, and the resulting pollution of MPs has become a global environmental problem. Plants can absorb MPs through their roots. However, studies on the mechanism of the effect of root exposure to different size MPs on vegetables are limited. Here, we use Polystyrene (PS) MPs with different particle sizes to investigate the internalization, physiological response and molecular mechanism of lettuce to MPs. MPs may accumulate in large amounts in lettuce roots and migrate to the aboveground part through the vascular bundle, while small particle size MPs (SMPs, 100 nm) have stronger translocation ability than large particle size MPs (LMPs, 500 nm). MPs can cause physiological and biochemical responses and transcriptome changes in lettuce. SMPs and LMPs resulted in reduced biomass (38.27 % and 48.22 % reduction in fresh weight); caused oxidative stress (59.33 % and 47.74 % upregulation of SOD activity in roots) and differential gene expression (605 and 907 DEGs). Signal transduction, membrane transport and alteration of synthetic and metabolic pathways may be the main causes of physiological toxicity of lettuce. Our study provides important information for understanding the behavior and fate of MPs in edible vegetables, especially the physiological toxicity of MPs to edible vegetables, in order to assess the potential threat of MPs to food safety and agricultural sustainable development.

Phytoremediation of quinclorac and tebuthiuron-polluted soil by green manure plants.

Quinclorac and tebuthiuron are residual herbicides that may remain in the soil longer than for the cropping season. The objective of this research was to evaluate the use of green manure plants to remediate soils treated with quinclorac and tebuthiuron. Soils were separately treated with 14C-quinclorac and 14C-tebuthiuron at 266.4 and 132 g ha-1, respectively. After 21 days, four green manure plants, namely Crotalaria spectabilis, Canavalia ensiformis, Stizolobium aterrimum, and Lupinus albus, were separately sown in the treated soils. Overall, all four species absorbed more 14C-tebuthiuron [C. ensiformes (22.49%), S. aterrimum (16.71%), L. albus (15%), and C. spectabilis (4.48%)] than 14C-quinclorac [C. ensiformis (13.44%), L. albus (10.02%), S. aterrimum (6.2%), and C. spectabilis (1.75%)]. Quinclorac translocation in all four plants was greater in young leaves compared to old leaves, cotyledons, or roots, and 14C-tebuthiuron translocation in all four plant species was greater in old leaves and cotyledons compared to young leaves or roots. Regardless of the differences in translocation between the two herbicides, the four green manure plants are capable to remediate soils that have been treated with quinclorac and tebuthiuron. However, C. ensiformis is more efficient for the remediation of tebuthiuron-treated soil compared to the other plants.

A New Luminescent Zn(II) Complex: Selective Sensing of Cr2O72- and Prevention Activity Against Orthodontic Root Absorption by Suppressing Inflammatory Response.

A novel luminescent coordination polymer (CP) based on Zn(II) ions as nodes [Zn(OPY)1.5(Hbtc)]n (1), [H3btc = trimesic acid and OPY = 4,4'-(oxybis(4,1-phenylene))dipyridine] has been prepared via the solvothermal assembly of a tripodal multicarboxylic acid ligand, a bis-pyridyl ligand with V-shape containing two diverse coordination patterns as well as Zn2 + ion. The experiments of photoluminescence also reflect that the coordination polymer 1 has high sensitivity to potassium dichromate, and its quenching efficiency is Ksv of 2.12 × 104 L·mol- 1. Furthermore, its treatment activity on orthodontic root absorption was evaluated in vivo. Firstly, the CCK-8 assay was performed in this research to evaluate the biotoxicity of the synthetic compound. Next, the TNF-α and Cbfα1 released by the periodontal ligament fibroblast was determined via the ELISA test kit. In addition to this, the signaling pathway of NF-κB activation after treated with compound was measured by the RT-PCR.

Phytoextraction of diuron, hexazinone, and sulfometuron-methyl from the soil by green manure species.

The herbicides diuron, hexazinone, and sulfometuron-methyl present a potential risk of environmental contamination and are widely used for weed control in sugarcane cultivation. Our objectives were to measure the tolerance of Canavalia ensiformes (L.) DC., Stilizobium aterrimum L., Raphanus sativus L., Crotalaria spectabilis Röth, Lupinus albus L., and Pennisetum glaucum (L.) R. Br. To the herbicides diuron, hexazinone, and sulfometuron-methyl to assess the capacity of these species to extract and accumulate the herbicides in their tissues. Before sowing the green manure species, the soils were individually contaminated with the three 14C-radiolabeled herbicides. 14C-diuron and 14C-sulfometuron-methyl showed higher values remaining in the soil (>90%) for all species of green manure compared to hexazinone (<80%). The green manure species analyzed showed greater potential to remedy soils contaminated with hexazinone than the other herbicides. C. ensiformes showed high phytoextraction of hexazinone when compared to the other species, removing 11.2% of the pollutant from the soil, followed by L. albus (8.6%), S. aterrimum (7.3%), R. sativus (4.8%), C. spectabilis (2.5%), and P. glaucum (1.1%). The results indicate that the phytoextraction of diuron, hexazinone and sulfometuron-methyl is dependent on the species of green manure and can be an important tool for the decontamination of areas polluted by these herbicides.

[Changes in root and alveolar bone before and after treatment by retracting the upper incisors].

OBJECTIVE: Using cone beam computed tomography (CBCT) in image measurement on the patients with maxillary protrusion, the study aims to identify the changes in root and alveolar bone before and after treatment by upper incisor retraction. METHODS: The study was conducted on 37 patients who have received orthodontic treatment from January 2014 to December 2015. The sample comprised 17 males and 20 females, with an average age of 14.5 years. The patients underwent extraction of bimaxillary premolars and given maximum anchorage to retract the upper incisors. The adducent angle, adducent amount, and the amount of elongation of the upper incisor teeth were measured by cephalograms. The patients were scanned by NewTom VGi to obtain CBCT data before and after treatment with upper incisor retraction. Using the NewTom NNT tool, we obtained the multiple planar reconstruction and then adjusted the coronal, axial, and sagittal axis. The sagittal section of the long axis of the maxillary central incisor through the incisal edge and root apex was selected to measure the changes in the root and alveolar bone before and after incisional treatment. RESULTS: Before and after retracting the upper incisors, the adducent angle of central incisor measured 12.92°±6.43°. Adducent amount of the incisors reached (5.54±2.21) mm. Incisor extension amount totaled (0.60±0.95) mm. Root absorption length was (0.81±0.46) mm. Root absorption rate was 6.80%±3.60%. Statistical differences were observed in the changes in root length before and after incisor retraction (P<0.05). After upper incisor retraction, increasing distance from the labial side alveolar ridge to the cemento-enamel junction reached (0.20±0.22) mm. After treatment, we observed that the height of the labial-side alveolar bones decreased and showed statistical difference with the height of labialside alveolar bones before treatment (P<0.05). The results show the correlation between root absorption and horizontal displacement of maxillary center incisor and the distance from the upper incisor apex to labial cortical bone. A correlation also exists between the variable quantity of the labial-side alveolar bones and adducent angle of the upper incisor, with a correlation coefficient of 0.354. The results also show significant difference (P<0.05). CONCLUSIONS: After compensatory treatment of patients with maxillary protrusion, the root length of upper incisor was absorbed remarkably. The height of the labial-side alveolar bones was reduced. A greater tooth movement or beyond the anatomical limitations and alteration limits of the alveolar bone can easily lead to root resorption. A negative correlation exists between the variable quantity of the labialside alveolar bones and adducent angle of the upper incisor.

Changes in root and alveolar bone before and after treatment by retracting the upper incisors / 华西口腔医学杂志

OBJECTIVE@#Using cone beam computed tomography (CBCT) in image measurement on the patients with maxillary protrusion, the study aims to identify the changes in root and alveolar bone before and after treatment by upper incisor retraction.@*METHODS@#The study was conducted on 37 patients who have received orthodontic treatment from January 2014 to December 2015. The sample comprised 17 males and 20 females, with an average age of 14.5 years. The patients underwent extraction of bimaxillary premolars and given maximum anchorage to retract the upper incisors. The adducent angle, adducent amount, and the amount of elongation of the upper incisor teeth were measured by cephalograms. The patients were scanned by NewTom VGi to obtain CBCT data before and after treatment with upper incisor retraction. Using the NewTom NNT tool, we obtained the multiple planar reconstruction and then adjusted the coronal, axial, and sagittal axis. The sagittal section of the long axis of the maxillary central incisor through the incisal edge and root apex was selected to measure the changes in the root and alveolar bone before and after incisional treatment.@*RESULTS@#Before and after retracting the upper incisors, the adducent angle of central incisor measured 12.92°±6.43°. Adducent amount of the incisors reached (5.54±2.21) mm. Incisor extension amount totaled (0.60±0.95) mm. Root absorption length was (0.81±0.46) mm. Root absorption rate was 6.80%±3.60%. Statistical differences were observed in the changes in root length before and after incisor retraction (P<0.05). After upper incisor retraction, increasing distance from the labial side alveolar ridge to the cemento-enamel junction reached (0.20±0.22) mm. After treatment, we observed that the height of the labial-side alveolar bones decreased and showed statistical difference with the height of labialside alveolar bones before treatment (P<0.05). The results show the correlation between root absorption and horizontal displacement of maxillary center incisor and the distance from the upper incisor apex to labial cortical bone. A correlation also exists between the variable quantity of the labial-side alveolar bones and adducent angle of the upper incisor, with a correlation coefficient of 0.354. The results also show significant difference (P<0.05).@*CONCLUSIONS@#After compensatory treatment of patients with maxillary protrusion, the root length of upper incisor was absorbed remarkably. The height of the labial-side alveolar bones was reduced. A greater tooth movement or beyond the anatomical limitations and alteration limits of the alveolar bone can easily lead to root resorption. A negative correlation exists between the variable quantity of the labialside alveolar bones and adducent angle of the upper incisor.

Agrobacterium-mediated transient expression via root absorption in flowering Chinese cabbage.

BACKGROUND: Because most transient transformation techniques are inadequate for functional genomics research in roots, we aimed to develop a simple and efficient Agrobacterium-mediated transient transformation system that utilized root absorption for research in flowering Chinese cabbage. RESULTS: Both semi-quantitative and fluorescent quantitative RT-PCR confirmed that the target gene BcAMT1;3 was more highly expressed in plants that were infected with the transformed Agrobacterium strain (EHA105-p35S-BcAMT1;3) than in control plants that were infected with the control strain (EHA105-p35S). Furthermore, GUS staining analysis conformed the availability of this transient transformation system. In addition, we found that the highest transformation efficiency was achieved using an Agrobacterium cell density of OD600 = 0.3 for 3-6 h, without hyperosmotic pretreatment, and under these conditions, the peak transformation efficiency was observed at 2 and 4 d after infection. CONCLUSIONS: The transformation method developed by the present study is simple and convenient, since no special equipment is required, and since the method causes no damage, the plants can be used for subsequent experiments.