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Cold stress resulting from chilling and freezing temperatures substantially inhibits plant growth and reduces crop production worldwide. Tremendous research efforts have been focused on elucidating the molecular mechanisms of freezing tolerance in plants. However, little is known about the molecular nature of chilling stress responses in plants. Here we found that two allelic mutants in a spliceosome component gene SmEb (smeb-1 and smeb-2) are defective in development and responses to chilling stress. RNA-seq analysis revealed that SmEb controls the splicing of many pre-messenger RNAs (mRNAs) under chilling stress. Our results suggest that SmEb is important to maintain proper ratio of the two COP1 splicing variants (COP1a/COP1b) to fine tune the level of HY5. In addition, the transcription factor BES1 shows a dramatic defect in pre-mRNA splicing in the smeb mutants. Ectopic expression of the two BES1 splicing variants enhances the chilling sensitivity of the smeb-1 mutant. Furthermore, biochemical and genetic analysis showed that CBFs act as negative upstream regulators of SmEb by directly suppressing its transcription. Together, our results demonstrate that proper alternative splicing of pre-mRNAs controlled by the spliceosome component SmEb is critical for plant development and chilling stress responses.

In recent years, group recommendation has become a research hotspot and focus in online social network community. Currently, several deep-learning-based approaches are leveraged to learn preferences of groups for items and predict the next items in which groups may be interested. Yet, their recommendation performance is still unsatisfactory due to the sparse group–item interactions. In order to address this problem, in this article, we introduce an effective model, namely Social Group Recommendation model with TrAdaBoost (SGRTAB), to raise the performance of group recommendation in online social networks. The SGRTAB model includes two stages: data preprocessing (DP) and model optimization (MO). In DP, SGRTAB produces inputs for MO and implements three related tasks: extracting individual features, handling group data via GloVe, and utilizing user contribute ratings to their own groups, whereas in MO, SGRTAB implements group preference learning with the assistance of user preference learning based on the TrAdaBoost algorithm. Specifically, SGRTAB can effectively absorb the knowledge of user preferences into the process of group preference learning through the idea of transferring-ensemble learning. Moreover, extensive experiments on four real-world data sets indicate that the proposed SGRTAB model significantly outperforms the state-of-the-art baselines for social group recommendation.

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MicroRNAs have been shown to be involved in various cell processes, including proliferation, apoptosis and differentiation. However, little is known about their function in granulopoiesis. In the present study, overexpression and knockdown experiments revealed that miR-15b was required to block the proliferation of NB4 and HL60 cells and induce them differentiated to granulocyte lineage. Moreover, we identified CCNE1 as a direct target of miR-15b, and demonstrated that CCNE1 was involved in cell differentiation and proliferation in acute promyelocytic leukemia cells. In addition, we demonstrated a novel pathway in which miR-15b regulated cells arrested in the G0/G1 phase and promoted terminal differentiation of cells by targeting CCNE1, which could modulate the cell cycle effort pRb in APL cells. These events blocked cell proliferation and promoted granulocyte differentiation. In conclusion, our data highlighted, for the first time, the important role of miR-15b in myeloid differentiation and suggested the potential role of miR-15b in cancer therapy.

The widespread agricultural problem of pre-harvest sprouting (PHS) could potentially be overcome by improving seed dormancy. Here, we report that miR156, an important grain yield regulator, also controls seed dormancy in rice. We found that mutations in one MIR156 subfamily enhance seed dormancy and suppress PHS with negligible effects on shoot architecture and grain size, whereas mutations in another MIR156 subfamily modify shoot architecture and increase grain size but have minimal effects on seed dormancy. Mechanistically, mir156 mutations enhance seed dormancy by suppressing the gibberellin (GA) pathway through de-represssion of the miR156 target gene Ideal Plant Architecture 1 (IPA1), which directly regulates multiple genes in the GA pathway. These results provide an effective method to suppress PHS without compromising productivity, and will facilitate breeding elite crop varieties with ideal plant architectures., Pre-harvest sprouting reduces the yield of agriculturally important crops such as rice. Here, the authors show that mutating specific members of the MIR156 gene family can suppress pre-harvest sprouting in rice without negative effects on plant architecture, suggesting a practical route to elite crop varieties.

RAS-responsive element-binding protein 1 (RREB1) is a transcription factor that is implicated in RAS signaling and multiple tumors. However, the role of RREB1 in acute myeloid leukemia has not been studied. We found that RREB1 is overexpressed in AML patients and myeloid leukemia cell lines (NB4 and HL-60), and RREB1 expression was significantly decreased during granulocytic differentiation of myeloid leukemia cells induced by all-trans retinoic acid (ATRA). Then we performed a RREB1 knockdown assay in NB4 and HL-60 cells; the results showed that knockdown of RREB1 upregulated expression of CD11b, CEBPβ, and microRNA-145 (miR-145), which hinted that knockdown of RREB1 enhanced granulocytic differentiation of myeloid leukemia cells. In addition, inhibitor of miR-145 can offset the enhanced effect on granulocytic differentiation mediated by downregulation of RREB1. These collective findings demonstrated that RREB1 blocks granulocytic differentiation of myeloid leukemia cells by inhibiting the expression of miR-145 and downstream targets of the RAS signal pathway. These may provide a promising therapeutic target for AML patients.

The impacts of sonication on the photosynthetic activity of Synedra sp. (diatom) and its mechanism were investigated for the first time. Three photosynthetic parameters, i.e., effective quantum yield (Φe), initial slope of rapid light curves (α) and maximum relative electron transport rate (rETRmax) were employed to evaluate its photosynthetic activity during sonication for the first time. The results showed that 600 kHz is the optimal frequency for the inhibition of the photosynthetic activity and biomass as the ultrasonic frequencies varied from 100 to 800 kHz. When the photosynthetic activity was inhibited to be not detected by sonication, Φe, α and rETRmax gradually recovered from 0 to 36.4%, 35.2% and 48.3% of that in the blank group, respectively, after 12-day cultivation (no sonication). However, the biomass was still suppressed to 9.2% of that in the blank after the same cultivation. A single time sonication treatment achieved better inhibition efficiency than the multiple times modes when their total sonication time was equal. The inhibition mechanism for the photosynthetic activity of Synedra sp. by sonication can be concluded as follows: at the early stage, the thylakoids membrane expansion and oscillation can lead to the structure damage of thylakoids; subsequently, OH oxidation is responsible for the chlorophyll-a degradation.

Abscisic acid (ABA) signaling is critical for seed germination and abiotic stress responses in terrestrial plants. Pre-mRNA splicing is known to regulate ABA signaling. However, the involvement of canonical spliceosomal components in regulating ABA signaling is poorly understood. Here, we show that the spliceosome component Sm core protein SmEb plays an important role in ABA signaling. SmEb expression is up-regulated by ABA treatment, and analysis of Arabidopsis smeb mutant plants suggest that SmEb modulates the alternative splicing of the ABA signaling component HAB1 by enhancing the HAB1.1 splicing variant while repressing HAB1.2. Overexpression of HAB1.1 but not HAB1.2 rescues the ABA-hypersensitive phenotype of smeb mutants. Mutations in the transcription factor ABI3, 4, or 5 also reduce the ABA hypersensitivity of smeb mutants during seed germination. Our results show that the spliceosomal component SmEb plays an important role in ABA regulation of seed germination and early seedling development.

A collaborative system including peroxymonosulfate (PMS) activation in a photocatalytic fuel cell (PFC) with an BiOI/TiO2 nanotube arrays p-n type heterojunction as photoanode under visible light (PFC(BiOI/TNA)/PMS/vis system) was established. Xenon lamp was used as the light source of visible light. A 4.6 times higher pseudo-first-order bezafibrate (BZF) degradation rate constant was achieved in this system compared with the single PFC(BiOI/TNA)/vis system. The radical quenching experiments revealed that the contribution of reactive oxidative species (ROS) followed the order of 1O2 ≈ h+ >> •OH > SO4•− >>O2•−. The EPR tests demonstrated that PMS addition enlarged the formation of 1O2, •OH and SO4•−, but suppressed O2•− yield. Interestingly, 1O2 was further proved to dominantly originated from the priority reaction between positive photoinduced holes (h+) and negatively charged PMS. Besides, N2-purging tests and density functional theory calculation indicated that PMS probably reacted with residual photoinduced electron (e−) on the more negative conduction band (CB) of BiOI to form •OH and SO4•−, but competed with dissolved oxygen. Other e− transferred to the less negative CB of TNA through p-n junction will efficiently move to cathode through the external circuit. The greatly promoted power generation of PFC system was observed after PMS addition due to extra h+ consumption and efficient e− separation and transfer. Besides, three possible pathways for BZF degradation were proposed including hydroxylation, fibrate chain substituent and amino bond fracture. This study can provide new insights into the mechanisms of PMS assisted photocatalysis and accompanying energy recovery.

Extracellular organic matter (EOM) is an important precursor of disinfection by-products (DBPs). Nowadays, little is known about changes in molecular weight (MW) and hydrophilic (HPI)/hydrophobic (HPO) fractions of EOM during the entire algal growth phase. In this study, a combined approach of fractionation procedure and parallel factor (PARAFAC) analysis was applied to characterize the EOM during the entire growth phase of two algal species (M. aeruginosa and Synedra sp.), and investigated the relationships between fluorescent component and the DBP formation potential (FP) in MW and HPI/HPO fractions. Thereinto, three components (including one protein-like component (C1), one humic-like component (C2), and one fulvic acid–like component (C3)) were identified by the PARAFAC model. For two algae, the HPI and high MW (> 100 kDa) fractions were both the main components of algal EOM in the three growth phases in terms of the dissolved organic carbon. The high MW fraction had more C1 compared with other MW fractions, especially for M. aeruginosa. Besides, the formation risk of EOM-derived DBPs from M. aeruginosa was lower than that from Synedra sp. The result of this study showed the FP of DBPs varied with fluorescent components of algal EOM fractions and also indicated that the humic-like substances were tended to form trichloromethane and the tryptophan-like substances were associated with dichloroacetic acid by canonical correspondence analysis for both two algae.

In this study, a new Fenton system combining electro-Fenton and bio-electro-Fenton (EF-BEF) processes was proposed for ENR degradation and swine wastewater treatment, and pitaya peel-derived carbon modified with sulfidised nanoscale zerovalent iron (SnZVI) was developed as a catalyst for the system. The as-prepared PPC-800 carbon displayed a hierarchical porous structure (693.5 m

Objective To investigate the inhibitory effect of abnormal nuclear localization of the nuclear localization signal-retinoic acid receptor α (NLS-RARα) on cell differentiation and its mechanism of nuclear transport. Methods Over-expression of HA-NLS-RARα and empty vector in HEK293T cells and U937 cells were achieved through a lentivirus vector and were assigned as NLS-RARα over-expression (NR) group and negative control (NC) group. Extracted nucleoproteins and cytosolic proteins of NC and NR groups of HEK293T cells and U937 cells were detected by Western blot analysis in order to demonstrate the localization of NLS-RARα. Meanwhile, immunofluorescence assay was performed to explore the localization of NLS-RARα. The real-time quantitative PCR and Western blot analysis were used to detect difference in the mRNA and protein expression of CD11b and CEBPβ in the NR cells treated with 1, 25-dihydroxyvitamin D3 (1, 25D3) compared with NC cells treated with 1, 25D3. Mass spectrometric analysis and co-immunoprecipitation were conducted to screen the transport proteins which were associated with NLS-RARα, which was followed by the verification of nuclear accumulation of NLS-RARα by the transfection of transport protein small interfering RNA. Results Western blot assay and immunofluorescence showed that NLS-RARα was mainly located in the nucleus. And the qRT-PCR analysis and western blot assay showed a significant decrease in the mRNA and protein expression of CD11b and CEBPβ in the NR group compared with the NC group. It demonstrated that NLS-RARα inhibited cell differentiation. Mass spectrometric analysis and COIP demonstrated that KPNA2 (importin α1) and KPNB1 (importin β1) interacted with NLS-RARα, and the knockdown of KPNA2/KPNB1 inhibited the nuclear accumulation of NLS-RARα. Conclusion Abnormal localization of NLS-RARα inhibits cell differentiation via binding to KPNA2 and KPNB1 into the nucleus.

In acute promyelocytic leukemia (APL), all-trans retinoic acid (ATRA) treatment induces granulocytic differentiation and maturation. MicroRNAs play pivotal roles in formation of the leukemic phenotype. Previously, microRNA-382-5p (miR-382-5p) was upregulated in acute myeloid leukemia (AML) with t(15;17). In the present study, we found that miR-382-5p expression was elevated with ATRA-induced differentiation of APL. To investigate the potential functional role of miR-382-5p in APL differentiation, an APL cell line was transfected with miR-382-5p mimics, inhibitors, or negative control (NC). The results showed in APL cell line NB4 that miR-382-5p downregulation upon ATRA treatment was a key event in the drug response. Mechanistic investigations revealed that miR-382-5p targeted the ATRA-regulated tumor suppressor gene PTEN through direct binding to its 3' UTR. Enforced expression of miR-382-5p or specific PTEN inhibitors inhibited ATRA-induced granulocytic differentiation via regulation of the cell cycle regulator cyclinD1. Conversely, PTEN overexpression promoted differentiation and enhanced sensitivity of NB4 cell line to physiological levels of ATRA. Finally, we found that PTEN overexpression restored PML nuclear bodies (NBs). Taken together, these results demonstrated that up-regulated miR-382-5p in NB4 cell line inhibited granulocytic differentiation through the miR-382-5p/PTEN axis, uncovering PTEN as a critical element in the granulocytic differentiation program induced by ATRA in APL.

© 2020 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

A majority of acute promyelocytic leukaemia (APL) cases are characterized by the PML-RARα fusion gene. Previous studies have shown that neutrophil elastase (NE) can cleave PML-RARα and is important for the development of APL. Here, we demonstrate that one of the cleavage products of PML-RARα, NLS-RARα, can block cell differentiation by repressing the expression of the target genes within the retinoic acid signalling pathway. The results of reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot analysis showed that NLS-RARα depressed the expression of the cell differentiation marker protein, CD11b and CEBPβ, as well as the retinoic acid signalling pathway target genes, RARβ and CEBPe. Studies have shown that NLS-RARα forms heterodimers with retinoid X receptor α(RXRα) and interacts with SMRT. When treated with all-trans retinoic acid (ATRA), NLS-RARα exhibits diminished transcriptional activity compared to RARα. Moreover, in the presence of high doses of ATRA, NLS-RARα could be degraded along with the consequent transactivation of retinoic acid signalling pathway target genes and cell differentiation induction in a dose- and time-dependent manner. Together, these results indicate that NLS-RARα blocks cell differentiation by inhibiting the retinoic acid signalling pathway.

Domestication has resulted in reduced salt tolerance in tomato. To identify the genetic components causing this deficiency, we performed a genome‐wide association study (GWAS) for root Na(+)/K(+) ratio in a population consisting of 369 tomato accessions with large natural variations. The most significant variations associated with root Na(+)/K(+) ratio were identified within the gene SlHAK20 encoding a member of the clade IV HAK/KUP/KT transporters. We further found that SlHAK20 transports Na(+) and K(+) and regulates Na(+) and K(+) homeostasis under salt stress conditions. A variation in the coding sequence of SlHAK20 was found to be the causative variant associated with Na(+)/K(+) ratio and confer salt tolerance in tomato. Knockout mutations in tomato SlHAK20 and the rice homologous genes resulted in hypersensitivity to salt stress. Together, our study uncovered a previously unknown molecular mechanism of salt tolerance responsible for the deficiency in salt tolerance in cultivated tomato varieties. Our findings provide critical information for molecular breeding to improve salt tolerance in tomato and other crops.

As sessile organisms, plants are highly sensitive to environmental stresses. In response to stresses, globally repressed translation initiation leads to stress granule (SG) formation. Protein liquid-liquid phase separation (LLPS) contributes to SG formation, but a direct link between protein LLPS and stress resistance has not yet been found in plants. Here, we report that two RNA-binding proteins, RBGD2 and RBGD4, function redundantly to improve heat resistance in Arabidopsis. RBGD2 and RBGD4 undergo LLPS in vitro and condense into heat-induced SGs in vivo via tyrosine residue array (TRA). Importantly, disrupting LLPS by mutating TRA abolishes RBGD2/4 condensation in SGs and impairs their protective function against heat stress (HS). Further study found that upon HS, the RBGD2/4 interaction network expands with additional SG proteins and heat-responsive mRNA. Our work shows a mechanistic basis that underlies protein LLPS in HS response in plants and suggests manipulation of protein LLPS as a general strategy to improve plant stress resistance.

Terrestrial plants must cope with drought stress to survive. Under drought stress, plants accumulate the phytohormone abscisic acid (ABA) by increasing its biosynthesis and decreasing its catabolism. However, the regulatory pathways controlling ABA catabolism in response to drought remain largely unclear. Here, we report that the flowering repressor SHORT VEGETATIVE PHASE (SVP) is induced by drought stress and associates with the promoter regions of the ABA catabolism pathway genes CYP707A1, CYP707A3 and AtBG1, causing decreased expression of CYP707A1 and CYP707A3 but enhanced expression of AtBG1 in Arabidopsis leaves. Loss-of-function mutations in CYP707A1 and CYP707A3 or overexpression of AtBG1 could rescue the drought-hypersensitive phenotype of svp mutant plants by increasing cellular ABA levels. Collectively, our results suggest that SVP is a central regulator of ABA catabolism and that a regulatory pathway involving SVP, CYP707A1/3, and AtBG1 plays a critical role in plant response to water deficit and plant drought resistance.

This study investigated phytoplankton and bacterioplankton communities by flow cytometer in a tributary backwater area of the Three Gorges Reservoir, China. Samplings were conducted in two cyanobacterial bloom periods (May and August) and no algal-blooms period (November) of 2014, representing three different operational stages of the reservoir, i.e., reservoir discharge period, fluctuating period in the summer flood season, and high water level in the impoundment period. Phyto- and bacterioplankton exhibit a wide range of variability along the depth profiles of the water column. In the investigated two cyanobacterial bloom periods, prokaryotes accounted for over 50% of the total phytoplankton. As for bacterioplankton, low nucleic acid bacteria were dominant in August and November. A positive correlation was observed between phytoplankton (pico- and nanophytoplankton), Chl a, and bacterioplankton. High nucleic acid groups and prokaryotes were highly coupled in May and August, which indicated that this high nucleic acid group could probably contribute to the explanation of cyanobacterial bloom formation in this area.

To date, the removal of harmful algae and specific algae metabolites (e.g., microcystins, odorous compounds and phycocyanin) by ultrasound has been confirmed. However, the effects of ultrasound on algal organic matter (AOM) variation have not been systematically investigated, which is of great necessity for the management of water safety and the practical application of ultrasound for algae control. This study investigated the effects of ultrasound at three typical frequencies on the degradation behaviors and characters of AOM, including their fluorescence properties, molecular weight and especially sample toxicity. The results showed effective growth inhibition of algae over 7 days after ultrasonic treatment at frequencies of 29.4, 470 and 780 kHz; however, extracellular AOM increased by 1.4%–147.2%, −2.1%–82.5% and 0.9%–90.8%, respectively. High-frequency ultrasound (470 and 780 kHz) had significantly better AOM degradation. The fluorescence pseudo first-order rate constant refers to the decrease in fluorescence and implicates AOM degradation. The rate constants of AOM components were 0.00178–0.00295, 0.00880–0.01763 and 0.00670–0.01319 for the 29.4, 470 and 780 kHz treatments (0.059 W/mL), respectively. Low-frequency sonication was dominated by limited pyrolysis and supercritical water oxidation (SCWO) and mainly caused non-fracture damage. In addition to pyrolysis and SCWO, high-frequency sonication included conspicuous hydroxyl radical oxidation that accounted for more than 60% of the degradation. During high-frequency sonication, some AOM (~25.1 kDa) was degraded into smaller products (0.8–2.0 kDa), and the degradation of the humic-like components was greater than that of the protein-like components. Moreover, high-frequency sonication caused an evident decrease in the toxicity of AOM. This study indicates that high-frequency ultrasound was a promising algae-controlling strategy with respect to effectiveness and safety.

The squat reinforced concrete (RC) shear wall having low aspect ratio is a crucial structural component for both conventional buildings and nuclear-related structures due to the substantial role in resisting the lateral seismic loading. The prediction model for shear capacity of these walls becomes essential in ensuring the seismic safety of the building. Therefore, a model to predict the shear strength of squat RC walls has been proposed using a hybrid intelligence algorithm including the artificial neural network and particle swarm optimization algorithm (ANN–PSO). A total of 139 test results of squat walls are collected and utilized to train and test the hybrid ANN–PSO model. The performance of the proposed model has been assessed against the other shear strength models. The proposed model demonstrates good prediction capability with high accuracy for predicting shear strength of the RC walls.

The degradation of ofloxacin (OFX) at low concentration in aqueous solution by UVA-LED/TiO2 nanotube arrays photocatalytic fuel cells (UVA-LED/TiO2 NTs PFCs) was investigated. TiO2 nanotube arrays (TiO2 NTs) photoanode prepared by anodization-constituted anatase–rutile bicrystalline framework. The results indicated that the degradation efficiency of OFX by UVA-LED/TiO2 NTs PFC was significantly enhanced by 14.3% compared with UVA-LED/TiO2 NTs photocatalysis. The pH affected the degradation efficiency markedly; the highest degradation efficiency (95.0%) and the pseudo-first-order reaction rate constant k value (0.049 min−1) were achieved in neutral condition (pH 7.0). The degradation efficiency increased with the increasing concentration of dissolved oxygen (DO) in the UVA-LED/TiO2 NTs PFC. The main reactive species of OFX degradation are positive holes (h+) and superoxide ion radicals (O 2 ·− ) in a DO sufficient condition. Furthermore, the possible pathways of OFX degradation were proposed.

The potential risks of sono-induced nitrosation and nitration side reactions and consequent toxic nitrogenous byproducts were first investigated via sono-degradation of diphenylamine (DPhA) in this study. The kinetic models for overall DPhA degradation and the formation of nitrosation byproduct (N-nitrosodiphenylamine, NDPhA) and nitration byproducts (2-nitro-DPhA and 4-nitro-DPhA) were well established and fitted (R2 > 0.98). Nitrosation contributed much more than nitration (namely, 43.3 - 47.3 times) to the sono-degradation of DPhA. The contribution of sono-induced nitrosation ranged from 0.4 to 56.6% at different conditions. The maximum NDPhA formation rate and the contribution of sono-induced nitrosation were obtained at 600 and 200 kHz, respectively, as ultrasonic frequencies at 200 to 800 kHz. Both NDPhA formation rate and the contribution of sono-induced nitrosation increased with increasing power density, while decreased with increasing initial pH and DPhA concentration. PO43-, HCO3-, NH4+ and Fe2+ presented negative impacts on sono-induced nitrosation in order of HCO3- >> Fe2+ > PO43- > NH4+, while Br- exhibited a promoting effect. The mechanism of NDPhA formation via sono-induced nitrosation was first proposed.

Drought is one of the most deleterious environmental conditions affecting crop growth and productivity. Here we report the important roles of a nuclear-encoded chloroplast protein, PsbP Domain Protein 5 (PPD5), in drought resistance in Arabidopsis (Arabidopsis thaliana). From a forward genetic screen, a drought-resistant mutant named ppd5-2 was identified, which has a knockout mutation in PPD5. The ppd5 mutants showed increased H(2)O(2) accumulation in guard cells and enhanced stomatal closure in response to drought stress. Further analysis revealed that the chloroplast-localized PPD5 protein interacts with and is phosphorylated by OST1, and phosphorylation of PPD5 increases its protein stability. Double mutant ppd5-2ost1-3 exhibited phenotypes resembling the ost1-3 single mutant with decreased stomatal closure, increased water loss, reduced H(2)O(2) accumulation in guard cells, and hypersensitivity to drought stress. These results indicate that the chloroplast protein PPD5 negatively regulates drought resistance by modulating guard cell H(2)O(2) accumulation via an OST1-dependent pathway. Interestingly, the thf1-1 mutant defective in the chloroplast protein THF1 displayed drought-resistance and H(2)O(2) accumulation similar to the ppd5 mutants, but the thf1-1ost1-3 double mutant resembled the phenotypes of the thf1-1 single mutant. These results indicate that both OST1-dependent and OST1-independent pathways exist in the regulation of H(2)O(2) production in chloroplasts of guard cells under drought stress conditions. Additionally, our findings suggest a strategy to improve plant drought resistance through manipulation of chloroplast proteins.

The influence of pH and dissolved oxygen (DO) on the degradation of ofloxacin (OFX) in water by UVA-LED/TiO

The present study aimed to investigate the biological role of the mitochondrial GTPase mitofusin-2 (MFN2) in bladder cancer. MFN2 mRNA expression in tumor and paired adjacent non-tumor tissues from 8 patients was investigated using reverse transcription-quantitative polymerase chain reaction analysis. Immunohistochemistry was used to investigate MFN2 expression in 117 bladder cancer specimens. The associations of MFN2 expression with clinicopathological parameters were evaluated statistically. In addition, the biological role of MFN2 in the proliferation, migration and invasion of bladder cancer cells was examined. It was identified that MFN2 expression was significantly downregulated in bladder cancer tissues compared with normal tissues. MFN2 expression was associated with tumor stage, tumor grade and lymph node status. Furthermore, patients with low MFN2 expression demonstrated a shorter overall survival time (P=0.025). MFN2 knockdown by small interfering RNA promoted cancer cell proliferation, migration and invasion in vitro, and enhanced tumor progression in vivo. Mechanistically, MFN2 was revealed to be involved in Wnt/β-catenin signaling. In conclusion, MFN2 may serve as a potential therapeutic target in the treatment of bladder cancer, and the progress of bladder cancer may be delayed by regulating MFN2 expression.

The fusion oncogene, promyelocytic leukemia (PML)-retinoic acid receptor-α (RARα), is crucial for acute promyelocytic leukemia (APL) pathogenesis. Previous studies have reported that PML-RARα is cleaved by neutrophil elastase (NE), an early myeloid-specific serine protease, leading to translocation of the nuclear localization signal (NLS) of the PML protein to the N-terminal of RARα. This study was designed to evaluate the value of NLS-RARα in the early diagnosis of APL. To investigate the potential functional role of NLS-RARα in leukemogenesis, HL-60 and U937 cell lines were transfected with NLS-RARα lentivirus and negative control (LVNC). The results showed that the induced expression of NLS-RARα down-regulated expressions of CD11b, CD11c, and CD14 compared to the LVNC group induced by 1α, 25-dihydroxyvitamin D3(1,25(OH)2D3). This suggested that NLS-RARα overexpression inhibited granulocytic and monocytic differentiation of myeloid leukemia cells. In addition, Wright-Giemsa staining, flow cytometry, respiratory burst assay, and NBT reduction assay all confirmed the importance of NLS-RARα in differentiation. The mechanistic investigations revealed that induced NLS-RARα expression inhibited 1,25(OH)2D3-induced granulocytic differentiation by regulating the cell cycle regulators p19INK4D, p21WAF1/CIP1, cyclinD1, cyclin E1, and pRB. Furthermore, the cleaved protein NLS-RARα enhanced the oncogenicity of U937 cells in NOD/SCID mice. These findings collectively demonstrated that NLS-RARα blocked granulocytic and monocytic differentiation of myeloid leukemia cells by inhibiting the downstream targets of the RARα signal pathway and the cell cycle. This may provide a promising new target and method for diagnosing and treating APL.

Ultrasound-enhanced coagulation is capable of effectively removing algal cells in algae-laden water. However, study differences in ultrasound settings, algal cell conditions and coagulant properties complicate the accurate evaluation of this technique for practical applications. No study has yet compared algae (and algal organic matters) removal among different frequencies of ultrasound in the ultrasound-coagulation process. In this study, the ultrasound at three typical frequencies, 29.4, 470 and 780 kHz, were applied for this purpose. The results showed that high-frequency ultrasound at 470 and 780 kHz had substantially greater improvement of coagulation than low-frequency ultrasound at 29.4 kHz (For example, the turbidity removal at 1 mg-Al/L of polymeric aluminum chloride increased by 204.2%, 571.9% and 563.2% under 29.4, 470 and 780 kHz ultrasound-coagulation, respectively, at 3.42 J/mL). Algal cells exhibited irreversible physical damage and the release of intracellular organic matters (such as odorous compounds) under low-frequency ultrasound with energy densities ≥ 3.42 J/mL, whereas high-frequency ultrasound was characterized by nonviolent impairment, including oxidative degradation and gas vacuole destruction (particularly reversible) resulting from ultrasound-induced radicals and cell resonance, respectively. Avoiding the severe destruction of algal cells is crucial for minimizing the toxicity and secondary pollution of the treated water. To achieve satisfactory removal, protected safety and better economy, the optimal energy density for each frequency was also determined. The findings from the analyses of the laboratory-cultured sample were confirmed via real eutrophic surface water. This study provides new insights and guidance for the ongoing study of harmful algal removal by ultrasound-enhanced coagulation.

An improved two-phase computational fluid dynamics (CFD) model has been developed by incorporation of Eulerian-Eulerian approach and user defined function (UDF) to address the liquid–gas flow and ozone reaction in an ozone contactor. Besides, a novel structure optimization design was proposed to improve the performance of contactor. Tracer residence time distribution (RTD) and distribution of CT value were applied as the indicators of contactor performance by conventional single phase model and improved two-phase model, respectively. The validation tests revealed that the improved two-phase CFD model is a reliable tool for the simulation of ozone contactor performance with good accuracy. The simulated results showed that this optimization design can greatly reduce the short-circuiting and dead zone in the contactor, along with the improvement of ozone mass transfer efficiency. Also much higher improvement of average CT value (310% increment) than the improvement of baffling factor (48.8% increment) denotes that the two-phase model is recommendable in the future study, and the use of baffling factor will underestimate the performance of ozone contactor.

Actin-like 6A (ACTL6A), a component of BAF chromatin remodeling complexes, is important for cell differentiation. Nevertheless, its role and mechanism in acute promyelocytic leukemia (APL) has not been reported. To identify the genes that may participate in the development of APL, we analyzed data from an APL cDNA microarray (GSE12662) in the NCBI database, and found that ACTL6A was up-regulated in APL patients. Subsequently, we investigated the function and mechanisms of ACTL6A in myeloid cell development. The expression of ACTL6A was gradually decreased during granulocytic differentiation in all-trans retinoic acid-treated NB4 and HL-60 cells, and phorbol myristate acetate-treated HL-60 cells. We also found that knockdown of ACTL6A promoted differentiation in NB4 and HL-60 cells, and decreased the levels of Sox2 and Notch1. Mechanistically, ACTL6A interacted with and was co-localized with Sox2 and p53. Meanwhile, CBL0137, an activator of p53, decreased the expression of ACTL6A and promoted differentiation in NB4 and HL-60 cells. These findings suggest that the inhibition of ACTL6A promotes differentiation via the Sox2 and Notch1 signaling pathways. Furthermore, the differentiation promoted by inhibiting ACTL6A could be regulated by p53 via its physical interaction with ACTL6A.

The effects of ultrasonic frequency, power intensity, temperature and sparged gas on the generation of nitrogenous by-products NO2− and NO3− have been investigated, and the new kinetics model of NO2− and NO3− generation was also explored. The results show that the highest primary generation rate of NO2− and NO3− by direct sonolysis in the cavitation bubbles (represented by k1′ and k2′, respectively) was obtained at 600 kHz and 200 kHz, respectively, in the applied ultrasonic frequency range of 200 to 800 kHz. The primary generation rate of NO2− (represented by k1′) increased with the increasing ultrasonic intensity while the primary generation rate of NO3− (represented by k2′) decreased. The lower temperature is beneficial to the primary generation of both NO2− and NO3− in the cavitation bubbles. The optimal overall yields of both NO2− and NO3− were obtained at the N2/O2 volume (in the sparged gas) ratio of 3:1 which is near to the ratio of N2/O2 in air. The dissolved O2 is the dominant oxygen element source for both NO and NO2, compared with water vapor. Ultrasonic irradiation can significant enhance the recovery rates of dissolved N2 and O2 and thus keep the N2 fixation reaction going even without aeration.

The influence of pH and dissolved oxygen (DO) on the degradation of ofloxacin (OFX) in water by UVA-LED/TiO2 nanotube arrays photocatalytic fuel cell (UVA-LED/TNA PFC) was investigated. The degradation pathway depended on the location of OFX frontier orbital with different ionization states and the role of reactive oxidative species (ROSs) played with varied pH and DO values. In presence of DO, the quencher tests revealed that O2- played a key role at pH 3.0, 7.0 and 11.0, while OH made its greatest contribution at pH 3.0 and the effect of h+ was largely inhibited at pH 11.0. Hydroxylation for cationic OFX was more significant, while demethylation and piperazinyl ring oxidation for anionic OFX occurred more quickly compared to other forms. Besides, zwitterionic OFX underwent decarboxylation and combination of demethylation & hydroxylation more easily. Much higher power generation was observed in presence of DO at pH 7.0, probably due to the enhanced adsorption of OFX on the TNA, and DO could amplify the electric potential between the two electrodes. The degradation efficiencies were almost the same in presence or absence of DO, but the pathways were different and e-aq may replace O2- as the leading ROSs in absence of DO.