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Background: Macrophage migration inhibitory factor (MIF), originally reported as an inflammation regulating molecule, is elevated in various cancer cells, which may promote carcinogenesis. Meanwhile, ISO-1 is a potent small molecular inhibitor of MIF, which has not been investigated in nasopharyngeal carcinoma (NPC), hence the impact of ISO-1 on NPC cells remains to be illustrated. Objective: This study intended to explore the biological function of ISO-1 in NPC cells in vitro and prove a possibility of ISO-1 being a novel agent in NPC treatments. Methods: Gene expression of MIF in Head and Neck squamous cell carcinoma was obtained from The Cancer Genome Atlas (TCGA) database. Nasal pharyngeal tissues were collected from adult patients undergoing nasopharyngeal biopsy for MIF level detection. Proliferation of NPC cell lines 5-8B and 6-10B was studied using Cell Counting Kit-8 (CCK-8) assay and plate-colony-formation assay, apoptosis was determined by flow cytometry and TUNEL staining, migration and invasion capacities were measured by wound-healing assay and transwell assay, all to explore the function of ISO-1 in NPC cells in vitro. Epithelial-to-mesenchymal transition (EMT) level of NPC cells was determined by Western blot analysis and immunofluorescence assay. Results: Transcript level of MIF was significantly higher in head and neck squamous cell carcinoma. Protein MIF was overexpressed in human NPC tissues compared to non-cancerous ones, and its expression could be compromised by ISO-1 in vitro. 100μM ISO-1 significantly hindered NPC cells' migration and invasion capacities in vitro but acted relatively poorly on proliferation and apoptosis. Immunofluorescence assay and Western blotting implied a downregulated EMT level through TGF-β/Smad4 axis in ISO-1 treated NPC cells compared to the vehicle Conclusion: This study indicated that MIF antagonist ISO-1 holds an impact on NPC progression by influencing the migration and invasion of NPC cells ISO-1 inhibits the EMT process of NPC cells through TGF-β/Smad4 axis, supporting that prudent application of ISO-1 may be a potential adjuvant treatment for NPC.

Even though nasopharyngeal carcinoma (NPC) is not common worldwide, it is a major public health burden in endemic areas. Distant metastasis often leads to a poor prognosis for NPC; therefore, new and effective anticancer strategies are needed. Ginkgolic acid (GA) is small-molecule compound existing in Ginkgo biloba that has various biologically relevant activities, including antitumor properties; however, its effects and mechanism of action in NPC are unknown. The effects of GA on NPC and such underlying mechanisms were investigated using 5-8F and CNE2 cells and NP69 human immortalized nasopharyngeal epithelial cells in this study. Moreover, the xenograft models were built to examine GA's effection in vivo. GA treatment decreased the survival and invasive capacity of 5-8F and CNE2 and induced their apoptosis, which varied with dose; this was accompanied by downregulation of B cell lymphoma (Bcl)2, upregulation of Bcl2-associated X protein, and activation of poly-ADP ribose polymerase, and caspase-9/-3. G0/G1 phase arrest was induced by GA in NPCs. It also reduced the expression of cyclin-dependent kinase 6 and its regulators cyclin D2 and cyclin D3. GA inhibited the activation of protein kinase B/nuclear factor signaling; this effect was potentiated with GA and 5-fluorouracil (5-FU), which also enhanced 5-FU-induced apoptosis. In summary, GA may be effective as an adjuvant to conventional chemotherapy drugs in preventing the progression of NPC.

This study selected Dendrobium officinale protocorms as the experimental material and used different light-quality treatments and calcium signalling inhibitors to explore the mechanism of the biological response of calcium to light quality. The results indicate that a 1:3 red:blue (R:B) light ratio promotes the accumulation of biomass and polysaccharides in the protocorm. Nevertheless, this effect can be entirely counteracted by calmodulin (CaM) inhibitors and calcium ion-chelating agents. The possible mechanisms of this effect are as follows: (1) The Ca2+-CaM signal-regulated photosynthetic apparatus is improved by the R:B 1:3 light, increasing the CaM content and Ca2+-ATPase activity. Thus, R:B 1:3 light increases the development of the photosynthetic apparatus in the D. officinale protocorm, enhances its photosynthetic productivity, and promotes the activities of sucrose phosphatase; accordingly, biomass and sucrose accumulation increase. (2) R:B 1:3 light enhances Ca2+-CaM signalling and regulates glycometabolic processes to promote the activities of sucrose synthase, thus increasing fructose and glucose levels and providing sufficient synthetic precursors to promote polysaccharide production.

Concrete is one of the most widely used construction materials for basic infrastructure worldwide, especially in developing areas undergoing rapid urbanization. However, concrete inhibits energy exchange between soil and other ecosystem components. To enhance the fluxion of information between ecosystems, surface vegetation, and basement soil, this paper aims to explore the tolerance of plants growing on PC. Therefore, we investigated two different PC sample groups with aggregate particle diameters of 5–10 and 15–20 mm. After curing, the samples were used to plant three ground cover plants (Cynodon dactylon(L.) Pers, Agrostis stolonifera, and Sasa argenteostriatus, e.g., Camus), and the results were compared with those from normal soil without PC underneath as a reference. During an observational period of 12 weeks, the growth and height of the plants were documented and analysed. The physiological indexes of free proline (Pro), malondialdehyde (MDA), chlorophyll (Chl), relative electrical conductivity (REC), and soluble protein (SP) were investigated. The correlations and significant differences between these indexes based on the treatments were analysed. Then, principal component analysis (PCA) was used to determine the main variables affecting plant growth. The results showed that there were significant differences between the PC groups and the natural growth group. The growth and height of the three plant species under near-natural (nonconcrete) conditions were better than those of the plants in the PC treatments. The plants in the large-particle concrete (LC) treatment group showed better adaptability than those in the small-particle concrete (SC) treatment group in terms of growth, although both PC treatments resulted in various degrees of damage. PCA showed that SP, REC, and MDA were the most influential factors on plant growth in this study.

Dwarf bamboo Sasa argenteostriata (Regel) E.G. Camus has previously been considered as potential plant for metal phytoremediation. However, the dynamic responses and correlations among physiological resistances to high-concentration Pb exposure have not been described to date. This study conducted four Pb treatments (0, 1500, 3000, and 4500 mg kg–1) to examine the physiological resistance responses at days 7, 14, and 21. The findings showed that S. argenteostriata can regulate both the enzymatic system and the nonenzymatic system to synergistically overcome Pb damage. In addition, a significant positive correlation was found between enzymes and nonenzymatic substances, which were particularly apparent with regard to the superoxide dismutase (SOD) activities with phytochelatins (PCs) levels, peroxidase (POD), and glutathione reductase (GR) activities with glutathione (GSH) levels, as well as catalase (CAT) and ascorbate peroxidase (APX) activities with soluble protein (SP) levels. Furthermore, Pb concentration was the main factor that induced the physiological responses of S. argenteostriata to Pb stress. The antioxidant enzyme system and the AsA–GSH cycle were dominant resistance mechanisms under 1500 mg kg–1 Pb. AsA–GSH cycle and plant cell chelation were dominant resistance mechanisms under 3000 mg kg–1 Pb. Antioxidant enzymes and plant cell chelation were dominant resistance mechanisms under 4500 mg kg–1 Pb. This study provides comprehensive evidence regarding how both enzymatic and nonenzymatic systems of S. argenteostriata cooperate to alleviate the high-concentration soil Pb stress. The results highlight the environmental remediation potential of this species for Pb-contaminated media.

The significant influence of •NO on the stress response is well established; however, the precise metabolic pathways of •NO and RNS under metal stresses remain unclear. Here, the key components of ROS and RNS metabolism under Cd stress were investigated with multi-level approaches using high-quality forage white clover (Trifolium repens L.) plants. For the studied plants, Cd disturbed the redox homeostasis, affected the absorption of minerals, and exacerbated the degree of lipid peroxidation, thus triggering oxidative stress. However, •NO was also involved in regulating mineral absorption, ROS-scavenger levels and mRNA expression in Cd-treated white clover plants. In addition, GSNOR activity was up-regulated by Cd with the simultaneous depletion of •NO generation and GSNO but was counteracted by the •NO donor sodium nitroprusside. Response to Cd-stressed SNOs was involved in generating ONOO- and NO2-Tyr in accordance with the regulation of •NO-mediated post-translational modifications in the ASC-GSH cycle, selected amino acids and NADPH-generating dehydrogenases, thereby provoking nitrosative stress. Taken together, our data provide comprehensive metabolite evidence that clearly confirms the relationships between ROS and RNS in Cd-stressed plants, supporting their regulatory roles in response to nitro-oxidative stress and providing an in-depth understanding of the interaction between two families subjected to metal stresses.

Lilium sargentiae E.H. Wilson (Liliaceae) is an ornamental and economic flowering bulb in China. Unfortunately, due to low natural bulb multiplication rates or long juvenile phases, commercial release of a new genotype may take 10 or even 20 years. In this study, bulbs were expanded in test tubes by adding sucrose, to shorten the duration of the commercial production cycle. Results indicated that when sucrose, with a concentration of 60 g l−1, was supplied to the culture medium, the bulblets could be most effectively induced and expanded. The effect of sucrose on the formation and expansion of L. sargentiae was obvious and dominant. It was not connected to the osmotic potential of sucrose, nor entirely explained by the function of sucrose as an energy and carbon source. We used sugar analogues in the culturing of explanted materials to research the effect of sucrose-specific signaling on bulblet formation and expansion. Results showed that exogenous 3-O-methyl glucose could not induce and expand test-tube bulblets, which was similar to mannose, whereas isomaltulose could generate similar results to those obtained with sucrose. The results further indicated that the specific signalling of sucrose could be responsible for the effect on bulblets formation and swelling. We used the exclusion method to confirm above results and hypothesis, and observed that only a small part of sucrose was transformed by cell wall invertase and entered the cells through hexose transporters, playing a certain effect on bulbelt growth and development through hexose or hexose signaling systems. Overall, the effect of sucrose on bulblet induction and swelling could be explained by sucrose-specific signaling. Furthermore, this effect has a direct correlation with the sucrose-specific vector.

Dwarf bamboo is a woody plant with potential for use in the remediation of Pb-contaminated soil. Due to its clonal growth habit, there are two keys to its application for continuous soil Pb remediation: 1) its ability to form shoots and grow into new bamboo normally under Pb stress and 2) the Pb tolerance and accumulation characteristics of this new bamboo. Here, 5 species of dwarf bamboo were treated with 2 levels of soil Pb stress (0 and 1500 mg kg−1). In the roots of 3 of the species (Sasa argenteostriata, Sasaella glabra, and Indocalamus decorus), Pb tended to be distributed along the cell wall and transported to vacuoles. In the other 2 species (Sasa auricoma and Sasa fortunei), Pb was arranged linearly along the cell wall. Under Pb treatment, the new bamboo of all species showed gradual physiological adaptation to Pb stress. Correlations of the net photosynthetic rate, superoxide dismutase activity, and free proline levels with Pb content in new leaves in November were all higher than those in July, though that of malondialdehyde content decreased, suggesting that new dwarf bamboo exhibits good soil Pb stress tolerance. Sasa argenteostriata and Indocalamus decorus consistently maintained higher antioxidant enzyme activities and free proline levels than the other species under Pb treatment, and the total biomass per pot of the new bamboo decreased the least compared to that in the Pb-free treatment for these two species. Therefore, these bamboo species may be used in the long-term continuous remediation of Pb-contaminated soil.

Cadmium (Cd) is a non-essential metallic element with potentially deleterious effects on plants, animals, and human health. Many studies have indicated that nitrogen (N) application can effectively alleviate Cd toxicity in plants. However, the function of nitrogen in this process remains unclear. In this study, high-throughput RNA sequencing and comparative analysis were carried out on poplar (Populus cathayana Rehd) trees treated with only Cd or co-treated with N and Cd, and both treatments were compared against a negative control (no Cd or N) and plants treated with only N. The results showed that approximately 48045828, 46712688, 46681202, and 48076990 clean reads were obtained in the control, Cd, N + Cd, and N treatments. Gene ontology and pathway enrichment analysis (KEGG) indicated that differentially expressed genes (DEGs) could be classified primarily into 144 pathways, among which 19 were related to heavy metal transportation and cell detoxification. The up- and down-regulated DEGs were predominately involved in glutathione (GSH) synthesis, cysteine (Cys), glycine (Gly), brassinosteroid (BR), and salicylic acid (SA)-related pathways. Real-time quantitative PCR (RT-qPCR) revealed that the expression profiles of DEGs were consistent with the results from RNA sequencing analysis. Eight candidate genes encoding GSH, Cys, Gly, BR, and SA were associated with detoxification of Cd and were selected for further screening. A schematic model to explain the involvement of DEGs and N in the Cd-responsive regulatory network is proposed. This study represents the first comprehensive transcriptome-based characterization of N- and Cd-responsive DEGs in poplar. These results provide fundamental insight into the molecular mechanism of N assistance in Cd detoxification. In addition, the results of this study build a solid foundation for further genetic manipulation of Cd accumulation in plants and for the development of phytoremediation approaches to reclaim Cd-contaminated soils.

Cadmium (Cd) and zinc (Zn) coexist in the environment but interact differently in plants. Cosmos bipinnatus has been potentially considered as a Cd-accumulator. Thus, this study investigated the detoxification mechanism in C. bipinnatus seedlings under Cd, Zn and Cd + Zn stresses. In the present study, the presence of Zn inhibited Cd uptake and translocation, whereas Cd merely hindered Zn uptake. The concentration of Cd in soluble fraction significantly decreased and Cd was bounded to the cell wall in root under Cd + Zn stress. Meanwhile, Zn and Cd mutually decreased their concentrations in the ethanol extractable form (FE) and water extractable form (FW) in roots and shoots. Furthermore, Cd + Zn stress enhanced the activities of superoxide dismutase (SOD, EC 1.15.1.1), peroxidase (POD, EC 1.11.1.7) and catalase (CAT, EC 1.11.1.6) compared to Cd stress alone. These results suggested that Zn effectively decreased Cd uptake and translocation, changed their subcellular distributions, regulated their chemical forms composition and increased antioxidative enzyme activities, thereby enhancing the tolerance to Cd in C. bipinnatus. This study physiologically revealed the interactive effect of Cd and Zn on the detoxification mechanism of Cd in C. bipinnatus and provided new information on phytoremediation of the heavy metal contaminated soils.

Forest therapy is a fast-growing treatment approach, as it has the potential to alleviate stressful life events and to improve psychological well-being and physical health. Bamboo forests are widespread in southwestern China. Nevertheless, a knowledge gap on the specific health benefits of bamboo forest (BF) therapy still exists. To explore the psycho-physiologic responses of participants to the effects of BF therapy, 60 male adults aged between 19 and 24, with similar healthy conditions, were selected to participate in this study. A one-group pretest&ndash, posttest design was used for the BF sites and the city site (CS) to compare the difference in the psycho-physiologic responses of participants before and after the test. Participants at the BF sites participated in a three-day bamboo forest therapy session, and those at the CS participated in a three-day urban program. Blood pressure, heart rate, and peripheral oxygen saturation were measured as the physical signs, and the profile of mood state (POMS) questionnaire was completed by the participants for the psychological evaluation. Blood was sampled, and natural killer (NK) activity, the number of NK cells, and the levels of corticosterone, granulysin, perforin, and granzyme A/B in peripheral blood lymphocytes (PBLs) were measured. All the measurements mentioned above were performed at 08:00 on the first and fourth days within the test. Results indicated that the three-day BF therapy was capable of enhancing positive mood states and also reducing negative mood states in the male participants. The blood pressure and heart rates of the male participants decreased, while the peripheral oxygen saturation increased after the three-day BF therapy session. Furthermore, BF therapy significantly increased NK activity and the number of NK cells and perforin-, granulysin-, and granzyme A/B-expressing cells and significantly decreased the corticosterone level in PBLs in the male participants. The three-day BF therapy session improved the psychological and physiological well-being and enhanced the immune functions of the male college students.

Bermudagrass (Cynodon dactylon (L.) Pers) turf is the most widely used turfgrass in urban landscapes. Large amounts of fertilizer are usually applied for maximum turf performance, while relatively little attention has been paid to efficient nutrient management of bermudagrass turf. The design opted for was a 3-factor and 5-level Central Composite Rotatable Design (CCRD) consisting of 24 experimental runs in the greenhouse with response surface methodology (RSM) and simulated regression modeling. The experiment covered in this study was carried out at Sichuan Agricultural University with the objectives of understanding the interactive effects of nitrogen, (N), phosphorus (P), and potassium (K) fertilization on the bermudagrass integrated turf performance (ITP) and optimizing the amount of N, P, and K required for optimum turf performance during establishment. The qualitative and quantitative relationships between bermudagrass and fertilization significantly affected the ITP. The N, P, and K Fertilization significantly influenced the percent grass cover, turf height, shoot dry weight, root dry weight, and total chlorophyll content. Fertilization with N and P significantly enhanced the tiller length, turf density, color, and total protein levels. Root length was augmented with the application of P and K. We found that 3-D surface plots indicated significant interactive effects of NP, NK, and PK on the ITP. A simulation optimization and frequency analysis indicated that the optimal combined amounts of these nutrients were N: 26.0&ndash, 27.6 g m&minus, 2, P: 24.2&ndash, 26.4 g m&ndash, 2, and K: 3.1&ndash, 5.0 g m&ndash, 2 during the establishment phase. The results suggest that optimized fertilization is key to sustainable nutrient management of bermudagrass integrated turf performance.

Dwarf bamboo Sasa argenteostriata (Regel) E.G. Camus is considered as potential plants for metal phytoremediation in previous filed observations. However, the mechanisms of lead (Pb) detoxification has not been described. The objective of this study was to explore the difference strategies or mechanisms of Pb detoxification in plant tissues. In this regard, four Pb treatments with hydroponics including 0 (control), 300, 600, and 900 mg L−1 were conducted to examine subcellular compartmentalization, Pb accumulation/species and antioxidant-assisted chelation. Our findings showed the retention of Pb by the whip-root system is one of its detoxification mechanisms to avoid damage the shoots. In addition, the cell wall retention is the dominant detoxification strategy of whips, new roots, old roots and new/old stems, while vacuolar compartmentalization is for new/old leaves. Interestingly, four low-mobility/-toxicity Pb species (i.e., FNaCl, FHAc, FHCl and FR) are distributed in roots, whips and stems, while two high-mobility/-toxicity Pb species (FE and FW) in leaves. The conversion of Pb to low-toxicity/-migration is a Pb-detoxification strategy in roots, whips and stems but not in leaves. Besides, the new/old roots and leaves can alleviate Pb damage through the synthesis of non-protein thiol, glutathione and phytochelatins. Among these, phytochelatins play a leading role in the detoxification in new/old roots, while glutathione is in new/old leaves. This study provides the first comprehensive evidence regarding the different strategies for Pb detoxification in dwarf bamboo tissues from physiological to cellular level, supporting that this plant could be rehabilitated for phytoremediation in Pb-contaminated media.

Bamboos are considered as potential plants for phytoremediation. However, the mechanisms of EDTA-assisted bamboo for lead (Pb) control has not been described. The objective of this study was to examine the tolerance and behaviors of Pb to screen bamboos for Pb-contaminated soil and to explore the effects of EDTA on their phytoremediation. In this regard, five dwarf bamboos were treated with various doses Pb (0–1500 mg kg−1) and/or EDTA (500 or 250–1000 mg kg−1) to investigate antioxidant systems and Pb accumulation/species. Our findings showed that different doses of Pb significantly affect lipid peroxidation and antioxidant compounds in studied bamboos. EDTA increased the absorption of soil Pb2+ in all tissues with increasing Pb doses, while the Pb concentrations in all bamboo roots was higher than those in other tissues. Among these plants, Arundinaria argenteostriata (AA) and A. fortunei (AF) showed greater oxidative tolerance than other bamboos. Moreover, Pb accumulation showed the highest values in AA and AF plants relative to other bamboos. With increasing EDTA doses, levels of reducible and residual Pb decreased but the weak acid-soluble and total Pb increased in Pb-stressed AA/AF soils. Similarly, EDTA increased Pb2+ concentration in both bamboo tissues, while the Pb2+ level in leaves was higher than that in other organs at the highest EDTA dose. This study provides the first comprehensive evidence regarding EDTA enhancing the availability, absorption, and translocation of Pb in bamboo/soil, suggesting the application of EDTA may be an effective strategy for phytoremediation with two Arundinaria bamboos in Pb-contaminated soils.

To date, several species of Asteraceae have been considered as Cd-accumulators. However, little information on the Cd tolerance and associated mechanisms of Asteraceae species Cosmos bipinnatus, is known. Presently, several physiological indexes and transcriptome profiling under Cd stress were investigated. C. bipinnatus exhibited strong Cd tolerance and recommended as a Cd-accumulator, although the biomasses were reduced by Cd. Meanwhile, Cd stresses reduced Zn and Ca uptake, but increased Fe uptake. Subcellular distribution indicated that the vacuole sequestration in root mainly detoxified Cd under lower Cd stress. Whilst, cell wall binding and vacuole sequestration in root co-detoxified Cd under high Cd exposure. Meanwhile, 66,407 unigenes were assembled and 41,674 (62.75%) unigenes were annotated in at least one database. 2,658 DEGs including 1,292 up-regulated unigenes and 1,366 down-regulated unigenes were identified under 40 μmol/L Cd stress. Among of these DEGs, ZIPs, HMAs, NRAMPs and ABC transporters might participate in Cd uptake, translocation and accumulation. Many DEGs participating in several processes such as cell wall biosynthesis, GSH metabolism, TCA cycle and antioxidant system probably play critical roles in cell wall binding, vacuole sequestration and detoxification. These results provided a novel insight into the physiological and transcriptome response to Cd in C. bipinnatus seedlings.

The worsening of Cadmium (Cd) pollution has intensified the urban ecological environment deterioration in the world. Purifying contaminated environment using the tall, colored-leaf woody plants has been proved as an aesthetically pleasing approach. However, the effects of Cd stress on colored-leaf woody plants have been little reported. Present hydroponic experiments were carried out to study the physiological and related anthocyanin biosynthesis genes responses to Cd stress in “Quanhong Poplar” plants. The experiments consisted of four Cd levels (0, 50, 100 and 150 μM). Leaves were sampled at 5, 10, 20, 30, 40, 50, and 60 days after the first treatment for detection of related enzyme activities and genes expression. The results showed that the plants treated with 100 or 150 μM Cd presented obvious toxicity symptom, i.e. the inhibition of growth and the decrease of chlorophyll and anthocyanin contents. However, plants growth was enhanced and the synthesis of chlorophyll, anthocyanin were promoted when the plants were subject to 50 μM Cd stress. Furthermore, the activities of relative enzymes as well as their genes expression were induced, which indicated that low concentration of Cd induced the anthocyanin accumulation in “Quanhong Poplar” plants, which suggested that using “Quanhong Poplar” to purify contaminated environment would be an aesthetically pleasing approach, which would not only remediate contaminated environments but also bring landscape effects.

The red-leaf coloration of Quanhong poplar (QHP) (Populus deltoides), resulting from a bud sport, is a distinctive trait conferring high ornamental value. However, the underlying molecular coloration mechanism of the red-leaf poplar remains unknown. In this study, tissue buds and leaves from mutant QHP(red)and its wild-type progenitor L2025 (green) were used to study the coloration mechanism by high-throughput RNA sequencing and comparative analysis of the transcriptomes. A total of 12,000 differentially expressed genes (DEGs) were obtained. Functional enrichment using Gene Ontology (GO) and, Genes and Genomes (KEGG) annotations showed that 4951 bud DEGs and 1927 leaf DEGs participate in many important biological and metabolic pathways, including anthocyanin biosynthesis. Importantly, some structural genes that contribute to photosynthesis were down-regulated, and some candidate genes involved in the biosynthesis of abscisic acid (ABA), ethylene and anthocyanin were up-regulated in the QHP mutant. The DEGs identified provided insight into the novel traits of the mutant. The unigene dataset that was used to discover candidate genes provides a comprehensive resource for molecular research in red-leaf poplar and may provide insight into coloration of other woody plants.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editors-in-Chief. The authors have plagiarized part of a paper that had appeared in Plant, CellEnvironment, 29 (2006) 1532-1544. https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-3040.2006.01531.x The images that were reused were: Fig. 1e, 1f, 1g, 1h, 2a, 2b, 2e, 2f. One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.

Despite numerous reports implicating nitric oxide (NO) in the environmental-stress responses of plants, the specific metabolic and ionic mechanisms of NO-mediated adaptation to metal stress remain unclear. Here, the impacts of copper (Cu) and NO donor (SNP, 50 μM) alone or in combination on the well-known medicinal plant Catharanthus roseus L. were investigated. Our results showed that Cu markedly increased Cu 2+ accumulation, decreased NO production, and disrupted mineral equilibrium and proton pumps, thereby stimulating a burst of ROS; in addition, SNP ameliorates the negative toxicity of Cu, and cPTIO reverses this action. Furthermore, the accumulations of ROS and NO resulted in reciprocal changes. Interestingly, nearly all of the investigated amino acids and the total phenolic content in the roots were promoted by the SNP treatment but were depleted by the Cu + SNP treatment, which is consistent with the self-evident increases in phenylalanine ammonia-lyase activity and total soluble phenol content induced by SNP. Unexpectedly, leaf vincristine and vinblastine as well as the total alkaloid content (ca. 1.5-fold) were decreased by Cu but markedly increased by SNP (+38% and +49% of the control levels). This study provides the first evidence of the beneficial behavior of NO, rather than other compounds, in depleting Cu toxicity by regulating mineral absorption, reestablishing ATPase activities, and stimulating secondary metabolites.

It is experimentally confirmed that tinned steel sheet can be completely purified by electrolyzing with caustic solution. The concentrations of NaOH-Na 2 CO 3 - and Na 2 SnO 3 -3H 2 O, and the temperature of electrolyte are important factors to influence the critical current density of passivation of Sn layer. These parameters are optimized by experiments with the orthogonal method.