Cyanobacterial harmful algal blooms (cyanoHABs) in freshwater lakes across the globe are often combined with other stressors. Pharmaceutical pollution, especially antibiotics in water bodies, poses a ...potential hazard in aquatic ecosystems. However, how antibiotics influence the risk of cyanoHABs remains unclear. Here, we investigated the effects of norfloxacin (NOR), one of the most widely used antibiotics globally, to a bloom‐forming cyanobacterium (Microcystis aeruginosa) and a common green alga (Scenedesmus quadricauda), under both mono‐ and coculture conditions. Taxon‐specific responses to NOR were evaluated in monoculture. In addition, the growth rate and change in ratio of cyanobacteria to green algae when cocultured with exposure to NOR were determined. In monocultures of Microcystis, exposure to low concentrations of NOR resulted in decreases in biomass, chlorophyll a and soluble protein content, while superoxide anion content and superoxide dismutase activity increased. However, NOR at high concentration only slightly affected Scenedesmus. During the co‐culture trials of Microcystis and Scenedesmus, the 5 μg · L−1 NOR treatment increased the ratio of Microcystis to co‐cultured Scenedesmus by 47.2%. Meanwhile, although Scenedesmus growth was enhanced by 4.2% under NOR treatment in monoculture, it was conversely inhibited by 63.4% and 38.2% when co‐cultured with Microcystis with and without NOR, respectively. Our results indicate that antibiotic pollution has a potential risk to enhance the perniciousness of cyanoHABs by disturbing interspecific interaction between cyanobacteria and green algae. These results reinforce the need for scientists and managers to consider the influence of xenobiotics in shaping the outcome of interactions among multiple species in aquatic ecosystems.
The role of hydrogen sulphide (H2S) in angiogenesis has been widely demonstrated. Vascular endothelial growth factor (VEGF) plays an important role in H2S‐induced angiogenesis. H2S promotes ...angiogenesis by upregulating VEGF via pro‐angiogenic signal transduction. The involved signalling pathways include the mitogen‐activated protein kinase pathway, phosphoinositide‐3 kinase pathway, nitric oxide (NO) synthase/NO pathway, signal transducer and activator of transcription 3 (STAT3) pathway, and adenosine triphosphate (ATP)‐sensitive potassium (KATP) channels. H2S has been shown to contribute to tumour angiogenesis, diabetic wound healing, angiogenesis in cardiac and cerebral ischaemic tissues, and physiological angiogenesis during the menstrual cycle and pregnancy. Furthermore, H2S can exert an anti‐angiogenic effect by inactivating Wnt/β‐catenin signalling or blocking the STAT3 pathway in tumours. Therefore, H2S plays a double‐edged sword role in the process of angiogenesis. The regulation of H2S production is a promising therapeutic approach for angiogenesis‐associated diseases. Novel H2S donors and/or inhibitors can be developed in the treatment of angiogenesis‐dependent diseases.
Hydrogen sulphide and nitric oxide interact and depend on each other to jointly regulate angiogenesis.
•A 3D sandwich structured AuNPs/MnO2/GP-CNTs hybrid has been prepared using three steps.•The priority of AuNPs/MnO2/GP-CNTs hybrid to CNTs, GP-CNTs and MnO2/GP-CNTs towards H2O2 responses was ...demonstrated.•The present H2O2 sensor showed ultrahigh detection sensitivity of 452 mA mM−1 cm−2 and low detection limit of 0.1 mM.
In this paper, a 3D sandwich structured hybrid of gold nanoparticles (AuNPs) decorated MnO2/graphene (GP)-carbon nanotubes (CNTs) was prepared via three steps, and the resultant AuNPs/MnO2/GP-CNTs hybrids was characterized by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX) detector and X-ray diffraction (XRD) spectrum, respectively. In this structure, the peeled GP nanosheets from CNTs work as linkers with CNTs to form 3D scaffold for facilitating fast electron conduction. The MnO2 nanoparticles well distributed on the GP-CNTs scaffold have excellent electrocatalytic activities towards H2O2, serving as active materials for fabricating electrochemical H2O2 sensors. AuNPs ( < 10 nm) uniformly distributed on the MnO2 surface not only further enhance the electric conductivity, but also provide a second active material for sensing H2O2. As a result, taking full advantage of the synergistic effect among AuNPs, MnO2 and GP-CNTs scaffold, the as-prepared AuNPs/MnO2/GP-CNTs hybrids showed excellent electrocatalytic activity towards H2O2 with ultrahigh detection sensitivity of 452 μA mM−1 cm−2 and low detection limit of 0.1 μM (S/N = 3). In addition, the prepared H2O2 sensor was applied for the determination of real samples with satisfactory results, indicating that the prepared sensors are promising in practical application.
The electrocatalytic ethanol oxidation reaction (EOR) is a critical component of direct ethanol fuel cells, while its reactivity, stability, and selectivity toward C
1
products are severely hindered ...by the poisoning effect of CO species on the surface of noble-metal catalysts. In this work, we developed a hybrid material of palladium nanoparticles and nickel single-atom catalysts (Pd NPs@Ni SAC) for efficient EOR. The Pd nanoparticles catalyze the breaking of carbon-carbon bonds of ethanol, while the adsorbed CO intermediates are removed by the Ni single-atom catalyst. The Pd NPs@Ni SAC structure exhibits outstanding EOR performances, including high mass activity, good selectivities of C
1
products, and excellent electrocatalytic stability. Our work suggests an attractive perspective of utilizing single-atom electrocatalysts for ethanol oxidation.
A Pd nanoparticle@Ni single-atomic catalyst (SAC) was developed for electrocatalytic ethanol oxidation. The Pd nanoparticles served as catalytic sites of ethanol, and the produced CO species adsorbed on Pd were electrochemically oxidized by Ni SAC.
A near-infrared fluorescent probe (TX-P) for detecting peroxynitrite is constructed. The probe has a near-infrared emission (725 nm), large Stokes shift (125 nm) and excellent sensitivity and ...selectivity. In addition, TX-P can be used to visualize ONOO
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in living cells, image ONOO
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in paw edema mice and evaluate anti-inflammatory drugs.
A near-infrared fluorescent probe (TX-P) for detecting peroxynitrite is constructed. The probe has long emission and large Stokes shift. TX-P can be used to visualize ONOO
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in cells, image ONOO
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in paw edema mice and evaluate anti-inflammatory drugs.
PI3K and STAT3 are frequently activated in cancer progression. However, little is known about the underlying mechanisms by which PI3K and STAT3 regulate head and neck squamous cell cancer (HNSCC) ...growth. The lncRNA HOX transcript antisense RNA (
) was found to modulate the progression of HNSCC. In this study, we attempted to establish the correlation of PI3K/STAT3/HOTAIR signaling with the progression of HNSCC and its sensitivity toward platinum-based and targeted anti-EGFR combination therapy.
We first analyzed the STAT3/HOTAIR and PI3K/AKT level in human HNSCC samples. We then activated or suppressed STAT3/HOTAIR and determined the effects on HNSCC cell proliferation
and the growth of UM1 xenograft tumor, an orthotopic model of HNSCC. The sensitivity of HNSCC cells toward cisplatin and cetuximab was determined by
assays.
HNSCC samples showed significantly robust expression/activation of STAT3, HOTAIR, PI3K, and AKT, compared with normal squamous epithelium. STAT3 inhibition with WP1066 decreased HOTAIR level and sensitized HNSCC to cisplatin or cetuximab. STAT3 promoted HOTAIR transcription and its interaction with pEZH2-S21, resulting in enhanced growth of HNSCC cells. In addition, overexpression of HOTAIR promoted the growth of UM1 xenograft tumors
Our results suggest that STAT3 signaling promotes HNSCC progression via regulating HOTAIR and pEZH2-S21 in HNSCC with PI3K overexpression/activation. These findings provide a rationale to target the STAT3/HOTAIR/pEZH2-S21 regulatory axis for treating patients with HNSCC.
.
Benzene is a global pollutant and has been established to cause leukemia. To better understand the role of DNA methylation in benzene toxicity, peripheral blood mononuclear cells were collected from ...six benzene-poisoning patients and six matched controls for genome-wide DNA methylation screening by Illumina Infinium Methylation 450 BeadChip. The Gene Chip Human Gene 2.0 ST Array (Affymetrix) was used to analyze global mRNA expression. Compared with the corresponding sites of controls, 442 sites in patients were hypermethylated, corresponding to 253 genes, and 237 sites were hypomethylated, corresponding to 130 genes. The promoter methylation and mRNA expression of CSF3R, CREB5, and F2R were selected for verification by bisulfite sequencing and real-time PCR in a larger data set with 21 cases and 23 controls. The results indicated that promoter methylation of CSF3R (p = .005) and F2R (p = .015) was significantly higher in cases than in controls. Correlation analysis showed that the promoter methylation of CSF3R (p < .001) and F2R (p < .001) was highly correlated with its mRNA expression. In the poisoning cases, neutrophil percentage was significantly different among the high, middle, and low CSF3R-methylation groups (p = .002). In particular, the neutrophil percentage in the high CSF3R-methylation group (48.10 ± 9.63%) was significantly lower than that in the low CSF3R-methylation group (59.30 ± 6.26%) (p = .012). The correlation coefficient between promoter methylation in CSF3R and the neutrophil percentage was -0.445 (p = .020) in cases and - 0.398 (p = .060) in controls. These results imply that hypermethylation occurs in the CSF3R promoter due to benzene exposure and is significantly associated with a reduction in neutrophils.
As the earliest commercial cathode material for lithium-ion batteries, lithium cobalt oxide (LiCoO
2
) shows various advantages, including high theoretical capacity, excellent rate capability, ...compressed electrode density, etc. Until now, it still plays an important role in the lithium-ion battery market. Due to these advantages, further increasing the charging cutoff voltage of LiCoO
2
to guarantee higher energy density is an irresistible development trend of LiCoO
2
cathode materials in the future. However, using high charging cutoff voltage may induce a lot of negative effects, especially the rapid decay of cycle capacity. These are mainly caused by rapid destruction of crystal structure and aggravation of interface side reaction at high voltage during the cycle. Therefore, how to maintain a stable crystal structure of LiCoO
2
to ensure the excellent long cycle performance at high voltage is a hot research issue in the further application of LiCoO
2
. In this review, we summarized the failure causes and extensive solutions of LiCoO
2
at high voltage and promoted some new modification strategies. Moreover, the development trend of solving the failure problem of high-voltage LiCoO
2
in the future such as defect engineering and high-temperature shock technique is also discussed.
Graphical abstract
This paper presents an adaptive control scheme via combining with an unknown system dynamics estimator (USDE) for attitude control of quadrotors subject to both parametric uncertainties and external ...disturbances. The presented controller is designed by effectively merging an adaptive control with an USDE via backstepping, where the extraneous uncertainties are addressed by USDE, and the adaptive law driven by tracking errors accounts for identifying unknown inertial moment constants. The unique characteristic is that a reinforced attitude controlling can be realized benefiting from the separate handling of parametric uncertainties and disturbances via an adaptive updating and a concise disturbance observation, significantly releasing the learning load of USDE and a high gain can be avoided in feedback loops. Meanwhile, Lyapunov analysis demonstrates that all error variables are uniformly ultimately bounded in the closed-loop system. Eventually, simulations substantiate the utility of suggested control strategy.
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