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Biochar has been widely recognized as an environmentally efficient adsorbent for removal of heavy metals in wastewater. However, inferior adsorption capacity limits its practical application. In this study, a H 3 PO 4 –modified tea branch biochar (PTBB) was firstly prepared through the one step pyrolysis of H 3 PO 4 -pretreated tea branch powder for enhancing removal efficiency of Cd2+ and Pb2+ from aqueous solutions. H 3 PO 4 modification altered the physicochemical properties of pristine biochar. The PTBB exhibited superior adsorption performance. Its maximum adsorption capacities of Cd2+ and Pb2+ were 98.25 mg g−1 and 127.5 mg g−1 at the pH 6 and dosage of 2 g L−1, which was 1.5 and 1.3 folds of the pristine biochar, respectively. Cd2+ and Pb2+ adsorption data by PTBB were well fitted by the Langmuir isothermal and pseudo-second order kinetic models, indicating monolayer chemical adsorption controlled the adsorption process. The adsorption of Cd2+ and Pb2+ by PTBB was a spontaneous endothermic process and less affected by coexisting cations. PTBB demonstrated a greater affinity for Pb2+ as compared with Cd2+ in binary metal systems. Moreover, PTBB could maintain good stability and regeneration properties. The adsorption of Cd2+ and Pb2+ by PTBB was attributed to cation exchange, precipitation, complexation, and π electron interactions. The quantitative analysis indicated that complexation and precipitation were the primary adsorption mechanisms, which accounted for 50.52–50.56% and 36.7–42.18% to total Cd2+ and Pb2+ adsorption for PTBB, respectively. Therefore, PTBB exhibits great potential for application in the remediation of wastewater containing Cd2+ or Pb2+. [Display omitted] • A novel H 3 PO 4 -modified biochar was prepared. • PTBB displayed superior Cd2+ and Pb2+ adsorption capacities. • PTBB enhanced Cd2+ and Pb2+ adsorption capacity by mineral precipitation and complexation. [ABSTRACT FROM AUTHOR]

Introduction Adenosine 5′-triphosphate (ATP) is a potent signaling molecule that regulates diverse biological activities in cells. Its effects on human dental pulp cells (HDPCs) remain unknown. This study aimed to examine the effects of ATP on proliferation and differentiation of HDPCs. Methods Reverse transcription polymerase chain reaction was performed to explore the mRNA expression of P2 receptor subtypes. Cell Counting Kit-8 test and flow cytometry analysis were used to examine the effects of ATP on proliferation and cell cycle of HDPCs. The effects of ATP on differentiation of HDPCs were examined by using alizarin red S staining, energy-dispersive x-ray analysis, Western blot analysis, and real-time polymerase chain reaction. Results The purinoceptors P2X3, P2X4, P2X5, P2X7, and all P2Y receptor subtypes were confirmed to present in HDPCs. ATP enhanced HDPC proliferation at 10 μmol/L concentration. However, it inhibited cell proliferation by arresting the cell cycle in G 0 G 1 phase ( P < .05 versus control) and induced odontoblastic differentiation, ERK/MAPK activation, and dentin matrix protein 1 (DMP1) and dentin sialophosphoprotein (DSPP) mRNA transcriptions at 800 μmol/L concentration. Suramin, an ATP receptor antagonist, inhibited ERK/MAPK activation and HDPC odontoblastic differentiation ( P < .05 versus control). Conclusions Extracellular ATP activates P2 receptors and downstream signaling events that induce HDPC odontogenic differentiation. Thus, ATP may promote dental pulp tissue healing and repair through P2 signaling. Results provide new insights into the molecular regulation of pulpal wound healing. [ABSTRACT FROM AUTHOR]

In this study, zinc oxide nanoparticles (ZnO NPs) were synthesized using leaf extract of Cinnamomum camphora (L.) Presl and zinc acetate. Its antifungal activity was evaluated against Alternaria alternata which caused early blight disease in Solanum lycopersicum. The results showed that the size of the synthesized ZnO NPs obviously depended on the pH during the reaction. The peak of the UV–Vis spectra was at 368–374 nm, which confirmed the synthesis of ZnO NPs. SEM showed that the synthesized ZnO NPs agglomerated into spherical particles. TEM reveled that the average particle sizes of ZnO NPs synthesized at pH 7, pH 8 and pH 9 were about 13.92, 15.19 and 21.13 nm, respectively. Furthermore, ZnO NPs treatments at 20–160 mg/L could significantly inhibit the mycelia growth of A. alternata , and ZnO NPs synthesized at pH 7 showed the best antifungal effect with MIC value recorded as 20 mg/L. Moreover, 20 mg/L ZnO NPs synthesized at pH 7 significantly limited spore germination and germ tube elongation of A. alternata. In addition, ZnO NPs induced excessive accumulation of MDA in A. alternata and caused the damage of cell membrane, leading to the leakage of protein and nucleic acid. Therefore, green synthesized ZnO NPs, as a promising biocontrol agent, could be used to control fungal diseases. [Display omitted] • ZnO nanoparticles (NPs) were synthesized via green synthesis using Cinnamomum camphora (L.) Presl leaf extract. • ZnO NPs were synthesized at pH 7–9 with the range of 13–22 nm. • ZnO NPs had significant antifungal activity. • The possible antifungal mechanism of ZnO NPs was related to lipid peroxidation and cellular leakage. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) and lead (Pb) pollution is a major environmental issue affecting plant production. Spermidine (Spd) is involved in plant response to abiotic stress. However, the role and associated mechanism of Spd under Cd + Pb combined stress are poorly understood. The potential protective role of Spd at different concentration on rice (Oryza sativa L.) seedlings exposed to Cd + Pb treatment was investigated by a hydroponic experiment in this study. The results showed that exogenous Spd enhanced the tolerance of rice seedlings to Cd + Pb stress, resulted in an increase in plant height, root length, fresh weight and dry weight of roots and shoots. Further, application of Spd decreased the contents of hydrogen peroxide, superoxide anion, malondialdehyde, and the accumulation of Cd and Pb, and increased the contents of mineral nutrient, carotenoids, chlorophyll, proline, soluble sugar, soluble protein, total phenol, flavonoid, anthocyanin, and antioxidant enzymes activities in roots and shoots of rice seedlings under Cd + Pb stress. Particularly, 0.5 mmol L−1 Spd was the most effective to alleviate the adverse impacts on growth and physiological metabolism of rice seedlings under Cd + Pb stress. Principal component analysis and heat map clustering established correlations between physio-biochemical parameters and further revealed Spd alleviated Cd + Pb damage in rice seedling was associated with inhibition of accumulation and translocation of Cd and Pb, increasing the contents of photosynthetic pigments and mineral nutrient and stimulation of antioxidative response and osmotic adjustment. Overall, our findings provide an important prospect for use of Spd in modulating Cd + Pb tolerance in rice plants. Spd could help to alleviate Cd + Pb damage through inhibition of accumulation and translocation of Cd and Pb and stimulation of oxidant-defense system and osmotic adjustment. • Cd and Pb combined stress affected the physiological and biochemical parameters that inhibit growth of rice plants. • Applied spermidine reduced the harmful effects induced by Cd and Pb. • Multivariate analysis demonstrated that spermidine promoted rice growth under Cd and Pb combined stress. • The best treatment for alleviating Cd and Pb combined stress is 0.5 mmol L−1 spermidine. [ABSTRACT FROM AUTHOR]

Ovarian cancer is the most lethal malignancy of the women genital tract. Exploring novel factors involved in the development of ovarian cancer and characterizing the molecular mechanisms by which regulate the tumorigenesis of ovarian cancer are quite necessary. Here, we found that miR-19a was highly expressed in ovarian cancer tissues and cell lines. Overexpression of miR-19a promoted the viability of ovarian cancer cells, while down-regulation of miR-19a inhibited the growth of ovarian cancer cells. To further understand the underlying molecular mechanism of miR-19a in regulating ovarian cancer cell growth, the downstream targets of miR-19a were predicted. The bioinformatics analysis showed that the tumor suppressor PTEN was found as one of the targeting candidates of miR-19a. MiR-19a bound the 3′-UTR of PTEN and highly expressed miR-19a decreased both the mRNA and protein levels of PTEN in ovarian cancer cells. Overexpression of PTEN suppressed the promoting effect of miR-19a on regulating the growth of ovarian cancer cells. Notably, the expression of miR-19a and PTEN was inversely correlated in ovarian cancer tissues. These results demonstrated the potential oncogenic role of miR-19a in ovarian cancer, which suggested that miR-19a might be a promising target in the diagnosis and treatment of ovarian cancer. [ABSTRACT FROM AUTHOR]

• EBR enhanced anthracnose resistance in mango fruit. • EBR showed no antifungal activity to C. gloeosporioides in vitro. • EBR enhanced defense-related enzyme activities. • EBR slowed down the hydrolysis of pectin. Brassinosteroids (BRs) are natural steroidal phytohormones that regulate many essential processes of plant growth, development and responses to stress. However, the role of BRs in the defense response against Colletotrichum gloeosporioides in mango fruit remains largely unknown. This study investigated the resistance against C. gloeosporioides and the possible mechanisms of exogenous 24-epibrassinolide (EBR) in mango fruit. Results showed 1 μmol L−1 EBR effectively reduced the disease incidence and disease severity on mango fruit after inoculating with C. gloeosporioides. However, EBR had no direct antifungal activity against C. gloeosporioides in vitro test. EBR significantly improved the activities of phenylalanine ammonia-lyase (PAL), peroxidase (POD), chitinase (CHT), cinnamate-4-hydroxylase (C4H), β-1,3-glucanase (GLU) and 4-hydroxycinnamate CoA ligase (4CL), as well as the accumulation of flavonoids, lignin and total phenolics in mango fruit. EBR treatment also increased hydrogen peroxide (H 2 O 2) content in mango fruit at early storage stage after inoculation, while increased catalase (CAT), ascorbate peroxidase (APX) and superoxide dismutase (SOD) activities with low reactive oxygen species (ROS) level in later storage stage. Besides, EBR treatment markedly reduced the changes in pectin methylesterase (PME) and polygalacturonase (PG) activities, which slowed down the hydrolysis of pectin, thus maintaining cell wall integrity. The principal component analysis indicated that EBR treatment was strongly associated with the increase of defense enzyme activities and metabolite contents and the inhibition of pectin hydrolysis. These results indicated that exogenous EBR could be a promising strategy to increase resistance against C. gloeosporioides in mango fruit by improving the defense responses against pathogens. [Display omitted] [ABSTRACT FROM AUTHOR]

Objective: To study the effectiveness of a dentifrice containing polymethyl vinyl ether-maleic acid (PVM/MA) copolymer in a silica base in occluding dentin tubules for treatment of dentin sensitivity.Methods: Thirty-two human dentin discs were divided into two groups and brushed in the morning for 30s each to study the dentifrices with and without PVM/MA copolymer. Dentin tubule occlusion and dentin permeability were evaluated with a focus variation three dimensional vertical scanning microscope (IFM) and electrochemical impedance spectroscopy (EIS). After second brushing for 30s in the afternoon the dentin discs were immersed in saliva for 16 h and then subjected to erosion using orange juice for 10 min. The effects of saliva and orange juice on tubule occlusion used in the study of dentifrices were further evaluated with IFM.Results: On average 97.7% of the dentin tubules were occluded after brushing in the PVM/MA group, as compared to 13.3% in the control group (p<0.0001). EIS showed that the impedance of the dentin disc increased after treatment with PVM/MA but not in the control group (p<0.05). After 16 h of storage in saliva and 10 min of erosion by orange juice, 86% of the dentin tubules remained occluded in the PVM/MA treated dentifrice. The sizes of the tubule openings were increased after orange juice erosion in the control group but not in the PVM/MA group.Conclusion: Dentifrice containing PVM/MA copolymer in a silica base effectively occluded dentin tubules. The intra-tubular plugs were resistant to saliva and orange juice challenges. [ABSTRACT FROM AUTHOR]