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Objective: Transient receptor potential (TRP) melastatin 7 (TRPM7) cation channel, a dual-function ion channel/protein kinase, regulates vascular smooth muscle cell (VSMC) Mg2+ homeostasis and mitogenic signaling. Mechanisms regulating vascular growth effects of TRPM7 are unclear, but epidermal growth factor (EGF) may be important because it is a magnesiotropic hormone involved in cellular Mg2+ regulation and VSMC proliferation. Here we sought to determine whether TRPM7 is a downstream target of EGF in VSMCs and if EGF receptor (EGFR) through TRPM7 influences VSMC function. Approach and results: Studies were performed in primary culture VSMCs from rats and humans and vascular tissue from mice deficient in TRPM7 (TRPM7+/Δkinase and TRPM7R/R). EGF increased expression and phosphorylation of TRPM7 and stimulated Mg2+ influx in VSMCs, responses that were attenuated by gefitinib (EGFR inhibitor) and NS8593 (TRPM7 inhibitor). Co-immunoprecipitation (IP) studies, proximity ligation assay (PLA) and live-cell imaging demonstrated interaction of EGFR and TRPM7, which was enhanced by EGF. PP2 (c-Src inhibitor) decreased EGF-induced TRPM7 activation and prevented EGFR–TRPM7 association. EGF-stimulated migration and proliferation of VSMCs were inhibited by gefitinib, PP2, NS8593 and PD98059 (ERK1/2 inhibitor). Phosphorylation of EGFR and ERK1/2 was reduced in VSMCs from TRPM7+/Δkinase mice, which exhibited reduced aortic wall thickness and decreased expression of PCNA and Notch 3, findings recapitulated in TRPM7R/R mice. Conclusions: We show that EGFR directly interacts with TRPM7 through c-Src-dependent processes. Functionally these phenomena regulate [Mg2+]i homeostasis, ERK1/2 signaling and VSMC function. Our findings define a novel signaling cascade linking EGF/EGFR and TRPM7, important in vascular homeostasis.

AIMS NOX-derived reactive oxygen species (ROS) are mediators of signaling pathways implicated in vascular smooth muscle cell (VSMC) dysfunction in hypertension. Among the numerous redox-sensitive kinases important in VSMC regulation is c-Src. However, mechanisms linking NOX/ROS to c-Src are unclear, especially in the context of oxidative stress in hypertension. Here we investigated the role of NOX-induced oxidative stress in VSMCs in human hypertension focusing on NOX5, and explored c-Src, as a putative intermediate connecting NOX5-ROS to downstream effector targets underlying VSMC dysfunction. METHODS AND RESULTS VSMC from arteries from normotensive (NT) and hypertensive (HT) subjects were studied. NOX1,2,4,5 expression, ROS generation, oxidation/phosphorylation of signaling molecules, actin polymerization and migration were assessed in the absence and presence of NOX5 (melittin) and Src (PP2) inhibitors. NOX5 and p22phox-dependent NOXs (NOX1-4) were downregulated using NOX5 siRNA and p22phox-siRNA approaches. As proof of concept in intact vessels, vascular function was assessed by myography in transgenic mice expressing human NOX5 in a VSMC-specific manner. In HT VSMCs NOX5 was upregulated, with associated oxidative stress, hyperoxidation (c-Src, peroxiredoxin, DJ-1) and hyperphosphorylation (PKC, ERK1/2, MLC20) of signaling molecules. NOX5 siRNA reduced ROS generation in NT and HT subjects. NOX5 siRNA, but not p22phox-siRNA, blunted c-Src phosphorylation in HT VSMCs. NOX5 siRNA reduced phosphorylation of MLC20 and FAK in NT and HT. In p22phox- silenced HT VSMCs, Ang II-induced phosphorylation of MLC20 was increased, effects blocked by melittin and PP2. NOX5 and c-Src inhibition attenuated actin polymerization and migration in HT VSMCs. In NOX5 transgenic mice, vascular hypercontractilty was decreased by melittin and PP2. CONCLUSIONS We define NOX5/ROS/c-Src as a novel feedforward signaling network in human VSMCs. Amplification of this system in hypertension contributes to VSMC dysfunction. Dampening the NOX5/ROS/c-Src pathway may ameliorate hypertension-associated vascular injury. TRANSLATIONAL PERSPECTIVE Oxidative stress is a major factor contributing to vascular damage in hypertension. We corroborate experimental evidence that NOX-derived ROS generation is increased in human vascular smooth muscle cells (VSMC) and demonstrate that in human hypertension NOX5 upregulation is a major trigger of VSMC dysfunction. We uncover new regulatory molecular mechanisms of NOX5 and define NOX5/ROS/c-Src as a novel signaling pathway in human VSMCs. This system is augmented in hypertension contributing to abnormal VSMC redox signaling, cytoskeletal disorganization and vascular dysfunction. Modulating the NOX5/ROS/c-Src pathway may have therapeutic potential by targeting redox signaling pathways involved in vascular dysfunction associated with hypertension.

There is an unmet clinical need to identify potential predictive biomarkers for immunotherapy efficacy in mismatch repair proficient (pMMR) metastatic colorectal cancer (mCRC). Heparanase (HPSE) is a multifunctional molecule mediating tumor–host crosstalk. However, the function of HPSE in the tumor immune microenvironment of CRC remains unclear. Data of CRC patients from public datasets (TCGA and GSE39582) and Zhongshan Hospital (ZS cohort) were collected to perform integrative bioinformatic analyses. In total, 1036 samples from TCGA (N = 457), GSE39582 (N = 510) and ZS cohort (N = 69) were included. Samples of deficient MMR (dMMR) and consensus molecular subtypes 1 (CMS1) showed significantly higher HPSE expression. The expression of HPSE also exhibited a significantly positive association with PD-L1 expression, tumor mutation burden and the infiltration of macrophages. Immune pathways were remarkably enriched in the HPSE high-expression group, which also showed higher expressions of chemokines and immune checkpoint genes. Survival analysis suggested that high HPSE expression tended to be associated with shorter overall survival in patients with pMMR mCRC. HPSE might contribute to the immune-activated tumor microenvironment with high levels of immune checkpoint molecules, suggesting that pMMR mCRC with high HPSE expression might respond to immune checkpoint inhibitors.

FeNiCeOx was firstly prepared by ultrasonic impregnation method and used to remove diclofenac in a Fenton-like system. The catalytic activity was improved successfully by doping Ni into FeCeOx. The diclofenac removal efficiency reached 97.9% after 30 min reaction. The surface morphology and properties of FeNiCeOx were characterized by Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), Raman and X-ray photoelectron spectroscopy (XPS) analyses. FeNiCeOx in this paper had larger specific surface area than those prepared by other methods, which was attributed to the cavitation effect and hot-spot effect during the ultrasonic synthesis process. Low crystallinity of Fe2O3 and NiO showed by characterization could lead to high interaction of Fe and Ni ions with support of CeO2. They substituted Ce in CeO2, caused lattice contraction and formed more oxygen vacancies, which favoured the catalytic reaction. Meanwhile, Fe and Ce ions both had redox cycles of Fe3+/Fe2+ and Ce4+/Ce3+, which facilitated the electron transfer in the reaction. The synergistic effect among Fe, Ni and Ce might lead to better catalytic performance of FeNiCeOx than any binary metal oxides constituted from the above three elements. Finally, the potential mechanism of diclofenac removal in FeNiCeOx-H2O2 system is proposed.

A series of Co3O4-CeO2 mixed metal oxides were synthesized by co-precipitation method and successfully used to activate persulfate for diclofenac removal. The effects of Co:Ce mole ratio, calcination temperature and calcination time on the catalytic activities were investigated. Results showed that the activity of Co3O4-CeO2 catalysts increased with Co:Ce mole ratio from 1:9 to 7:3, and decreased with the calcination temperature from 300 to 800 °C. 90% diclofenac was removed with Co7Ce3-300-1 catalyst (Co:Ce = 7:3, calcinated at 300 °C for 1 h) after 15 min. Moreover, short calcination time and low temperature resulted in smaller crystallite size, more structural defects, more active crystal surfaces and larger surface area of the catalyst, which led to higher removal efficiency of diclofenac. The high ratios of Co2+/Co3+, Ce3+/Ce4+ and Oads/Olatt were very important to enhance the catalytic activity. Finally, a potential reaction mechanism was proposed based on characterization of the fresh and spent catalysts.

There is great potential for nitrogen removal in wastewater treatment by photosynthetic bacteria (PSB) bioconversion. Protein-rich cells can be cultured simultaneous to nitrogen removal. For the first time, efficient nitrogen source range, kinetics of nitrogen removal and biomass accumulation of PSB bioconversion technology were studied. Results are that efficient nitrogen range is 3–8000 mg·L−1, which covers most wastewaters. Biokinetics was fit to Michaelis–Menten model, Monod model and inhibition models including Haldane, Edwards, and Aiba models. The data were best fitted by Aiba model, with an R2 of 0.97. Vmax, Km, and Ki of nitrogen degradation were 0.065 d−1, 1344 mg·L−1, and 6525 mg·L−1, respectively, and μmax, Ks, and Ki of biomass accumulation were 5.88 d−1, 883 mg·L−1, and 1521 mg·L−1, respectively. PSB bioconversion technology is more suitable than others for high nitrogen wastewater treatment.

Epidermal growth factor (EGF), signals throught the EGF receptor (EGFR) and plays an important role in the pathogenesis of vascular remodeling. Transient receptor potential melastatin 7 (TRPM7) is a channel bound to a kinase domain important for Mg 2+ , Zn 2+ and Ca 2+ homeostasis. Cancer patients treated with EGFR inhibitors develop hypomagnesemia, suggesting a relationship between EGFR and TRPM7. Here we investigated the role of TRPM7 in EGF signaling in vascular smooth muscle cell (VSMC) from humans (hVSMC) and rats (rVSMC). VSMCs were stimulated with EGF (50ng/ml) for 5min and 24h with/without pretreatment of gefitinib (1μM), PP2 (10μM), 2APB (30μM) and NS8593 (40μM), inhibitors of EGFR, c-Src kinase and TRPM7 respectively. Aortas were isolated from wild type (WT), TRPM7-deficient (TRPM7 +/Δkinase ) and kinase-dead (TRPM7 R/R ) mice. Protein expression was assessed by immunoblotting. Ca 2+ and Mg 2+ were assessed using Cal-520 and Mg-green probes respectively. EGFR/TRPM7 interaction was investigated by proximity ligation assay (PLA), immunoprecipitation and confocal microscopy. VSMC migration and proliferation were examined by wound healing and CFSE proliferation assays. In hVSMC and rVSMC, EGF increased TRPM7 expression (47%) and phosphorylation (21%), (p2+ and Ca 2+ influx was attenuated by gefitinib (4% and 8% respectively), NS8593 (5% for Mg 2+ ) and 2-APB (6% and 13% respectively). EGF enhanced ERK1/2 phosphorylation (3-fold) through c-Src, EGFR and TRPM7, p+/Δkinase showed reduced EGFR expression (73%), phospho-c-Src (22%), and phospho-ERK1/2 (90%). Aortas from TRPM7 R/R exhibited reduced phospho-EGFR (63%) and phospho-ERK1/2 (36%). Vessels from TRPM7 +/Δkinase showed reduced wall thickness (35%). Our findings demonstrate that interaction between EGFR/TRPM7 is a key process underlying EGF-induced VSMC migration and growth. This novel EGF-c-Src-EGFR-TRPM7 pathway may play an important role in vascular remodeling.

TRPM7 has cation channel and kinase properties, is permeable to Mg 2+ , Ca 2+ , and Zn 2+ and is protective in the cardiovascular system. Hyperaldosteronism, which induces hypertension and cardiovascular fibrosis, is associated with Mg 2+ wasting. Here we questioned whether TRPM7 plays a role in aldosterone- induced hypertension and fibrosis and whether it influences cation regulation. Wild-type (WT) and TRPM7-deficient (M7+/Δ) mice were treated with aldosterone (600μg/Kg/day) and/or 1% NaCl (drinking water) (aldo, salt or aldo-salt) for 4 weeks. Blood pressure (BP) was evaluated by tail-cuff. Vessel structure was assessed by pressure myography. Molecular mechanisms were investigated in cardiac fibroblasts (CF) from WT and M7+/Δ mice. Protein expression was assessed by western-blot and histology. M7+/Δ mice exhibited reduced TRPM7 expression (30%) and phosphorylation (62%), levels that were recapitulated in WT aldo-salt mice. M7+/Δ exhibited increased BP by aldo, salt and aldo-salt (135-140mmHg) vs M7+/Δ-veh (117mmHg) (p2+ -dependent phosphatase, was reduced (3-fold) only in M7+/Δ mice. M7+/Δ CF showed reduced proliferation (30%) and PPM1A (4-fold) and increased expression of TGFβ, IL-11 and IL-6 (2-3-fold), activation of Stat1 (2-fold), Smad3 (9-fold) and ERK1/2 (8-fold) compared with WT. Mg 2+ supplementation normalized cell proliferation and reduced protein phosphorylation in M7+/Δ CF (p2+ -dependent mechanisms.

Nox5 is the major ROS-generating Nox isoform in human vascular smooth muscle cells (VSMC). The role of Nox5 in oxidative stress and redox signaling underlying vascular dysfunction in hypertension is unclear. We examined molecular processes that regulate VSMC Nox5-induced ROS generation, focusing on c-Src. VSMC isolated from small arteries from normotensive (NT) and hypertensive (HT) subjects were studied. Nox5 expression and phosphorylation (immunoblotting, immunoprecipitation); ROS generation (chemiluminescence); activation of contractile signaling pathways (immunoblotting), Ca 2+ influx (Cal-520AM fluorescence), reversible protein oxidation (cysteine sulfenic acid probe BCN-E-BCN), actin polymerization (phalloidin staining) and migration (wound healing assay) were assessed in absence/presence of Nox5 (melittin) and Src (PP2) inhibitors. To study Nox5-specific effects, we used p22phox-silenced VSMCs (siRNA). Vascular function in VSMC-specific Nox5 transgenic mice was studied by wire myography. In HT, ROS levels (139±27%), Nox5 expression (103±23%) and phosphorylation were increased (77±17.93%) (p20 (416±71%) and Ang II-induced Ca 2+ influx (574±44 vs NT:451±26) were also increased in HT (p20 (89±22% vs Ctl) phosphorylation, effects blocked by melittin and PP2 (p2+ influx, actin polymerization and migration in HT. Hypercontractility observed in Nox5 mice was abolished by melittin and PP2. Our findings demonstrate that Nox5 is upregulated in human hypertension. This is associated with activation of c-Src, increased redox signaling and VSMC cytoskeletal reorganization, migration and vascular contraction. We define a novel Nox5-ROS-c-Src signaling pathway that may play a role in vascular remodeling/dysfunction in hypertension.

Photosynthetic bacteria (PSB) were reported to have great potential for nitrogen removal when treating high-ammonia wastewater. Light-oxygen conditions are the most important parameter; however, the role of the microbial community composition for PSB nitrogen removal remains unclear. This study focussed on the effects of three light-oxygen conditions on PSB performance and the microbial community during high-ammonia wastewater treatment. The results showed that light-oxygen conditions had a significant impact on nitrogen removal efficiency, microbial community diversity and composition. PSB under light-aerobic condition had the highest biomass, highest COD, NH4+-N, and NO3−-N removal efficiency, and the highest community diversity; these results have not been reported before. The dominant genus in samples under light-aerobic condition was Pseudomonas (with a proportion of 58.23%). The correlation analysis showed that Pseudomonas was positively correlated with NH4+-N and NO3−-N removal, with high correlation coefficients of 0.9. These results further revealed the underlying nitrogen removal mechanism of PSB in high-ammonia wastewater treatment.

TRPM7 is a chanzyme that influences cellular Mg 2+ homeostasis and vascular signaling. We demonstrated that aldosterone mediates cellular effects through TRPM7-dependent signaling pathways. Since hyperaldosteronism causes hypertension and Mg 2+ wasting, we questioned whether TRPM7 plays a role in aldosterone-induced hypertension. Wild-type (WT) and TRPM7-deficient (M7+/Δ) mice were treated with aldosterone (600μg/Kg/day) and/or 1% NaCl (drinking water) (aldo, salt or aldo/salt) for 4 weeks. Blood pressure (BP) was evaluated by tail-cuff. Vessel function was investigated in mesenteric arteries by wire and pressure myography. Protein expression was assessed by western-blot and histology. Cardiac fibroblasts (CF) were isolated from WT and M7+/Δ. M7+/Δ exhibited increased BP by aldo (140mmHg), salt (135mmHg) and aldo/salt (137mmHg) vs M7+/Δ-veh (117mmHg) (p

TRPM6 and 7 are channels important in Mg 2+ and Ca 2+ homeostasis. We demonstrated that TRPM7 is influenced by angiotensin II. TRPM6 is influenced by EGF and cancer patients treated with EGFR inhibitors exhibit hypomagnesemia and hypertension by unclear mechanisms. Whether growth factors influence vascular TRPM7 is unknown. Here we questioned if VEGF/EGF mediate vascular effects through TRPM7. Studies were performed in human VSMC, wild type (WT) and TRPM7-deficient (M7+/Δ) mice. VSMC were stimulated with VEGF or EGF (50ng/ml) in the absence/presence of vatalanib, gefitinib (1μM), 2APB (30μM) and NS8593 (40μM), inhibitors of VEGFR, EGFR and TRPM7 respectively. Ca 2+ and Mg 2+ levels were assessed by Cal-520 and Mg-green. VEGF/EGF signaling was assessed by immunoblotting and vascular function by myography in mesenteric arteries from WT and M7+/Δ mice and treated with EGF or VEGF (50ng/ml). TRPM7 expression in aortas and kidneys from WT treated with vatalanib or gefitinib (100mg/Kg/day, 2 weeks) was assessed by immunoblotting. VEGF and EGF increased TRPM7 expression (50% and 67% respectively) and phosphorylation (2-fold), promoted influx of Ca 2+ (8% and 10%) and Mg 2+ (8%), effects that were reduced by vatalanib, gefitinib, NS8593, and 2-APB. EGF but not VEGF increased phosphorylation of PKC (43%), p38MAPK (47%), and ERK1/2 (120%). These responses were reduced by gefitinib, however only ERK1/2 phosphorylation was inhibited by NS8593, and 2-APB. Mice treated with vatalanib or gefitinib showed reduced expression of TRPM7 in aortas (50% and 74% respectively) and kidneys (36% and 66% respectively). Vessels exposed to EGF were less responsive to acetylcholine (ACh)-induced relaxation, [Emax %: WT (veh 97±3 vs EGF 63±10, p2+ and Ca 2+ are important.

FeNiCeO

Tetracycline is a typical antibiotic that is eco-toxic and easily causes bacterial resistance, and thus it is necessary to eliminate tetracycline from the water environment. In this work, γ-Fe2O3/CeO2 was prepared and used to activate persulfate for tetracycline degradation. The catalyst was characterized by XRD, VSM and XPS, and results showed that it had excellent crystallinity and magnetism. The low valence metals (Fe (II) and Ce (III)) in γ-Fe2O3/CeO2 benefited persulfate activation. Tetracycline removal efficiency reached 84% with the γ-Fe2O3/CeO2/persulfate system; and the value was 70% in the surface water matrix. In addition, γ-Fe2O3/CeO2 kept high activity from pH 3 to 9. It had high stability and reusability and was easily recycled from solution due to its good magnetism. Mechanism analyses showed that SO4 − and OH on catalyst surface catalyst were the major active species, O2 − and 1O2 were also produced due to the excess oxygen vacancies of catalyst. Moreover, the degradation products of tetracycline were determined, and the degradation pathway was proposed. Hydroxylation, demethylation, decarbonylation, dehydroxylation, C-N bond cleavage and ring-opening were the main pathway. The cost of wastewater treatment with the γ-Fe2O3/CeO2/persulfate system was estimated to be 0.106 $/m3. This study provided an efficient and stable catalyst for tetracycline degradation.

A series of Co

Photosynthetic bacteria consortium was isolated from sediment of black odorous river and was named HJ-1. The main pigments were bacteriochlorophyll a and carotenoid. Fructose, mannosej, ethanol, sorbitol, and sodium acetate could be used as carbon source. 16S rDNA gene sequence analysis showed that the dominant strains were Rhodovulum strictum and Thiococcus pfennigii. Its organics-degrading capability was tested using low COD soybean wastewater, low COD brewery wastewater, low COD sugar wastewater and municipal wastewater. Results showed that the COD in all wastewater reached under 100 mg/L within 72 h. COD removal and biomass accumulation were realized. This study suggested the feasibility of COD degradation and resource recovery by HJ-1 in low COD wastewater.

In order to achieve simple pollutant removal and simultaneous resource recovery in high-COD-non-toxic wastewater treatment, a one-step photosynthetic bacteria (PSB) method was established using batch study experiment. The effluent COD met the national discharge standard, and biomass with rich protein and high-value substances was efficiently produced. It eliminated the demand of post-treatment for conventional PSB treatment. Results showed that Rhodopseudomonas effectively treated brewery wastewater and achieved biomass proliferation. Yeast extract was the best additive for PSB growth and the effluent COD was below 80 mg/L with 400 mg/L yeast extract, meeting the national discharge standard. In addition, the PSB biomass increased by 2.6 times, and the cells were rich in protein, polysaccharide, carotenoids, bacteriochlorophyll and coenzyme Q10, reaching 420.9, 177.6, 2.53, 10.75 and 38.6 mg/g respectively. This work demonstrated the great potential of PSB for high-COD non-toxic wastewater treatment in one-step process.

The transient receptor potential melastatin-subfamily member 7 (TRPM7) is a ubiquitously expressed chanzyme that possesses an ion channel permeable to the divalent cations Mg2+, Ca2+, and Zn2+, and an α-kinase that phosphorylates downstream substrates. TRPM7 and its homologue TRPM6 have been implicated in a variety of cellular functions and is critically associated with intracellular signaling, including receptor tyrosine kinase (RTK)-mediated pathways. Emerging evidence indicates that growth factors, such as EGF and VEGF, signal through their RTKs, which regulate activity of TRPM6 and TRPM7. TRPM6 is primarily an epithelial-associated channel, while TRPM7 is more ubiquitous. In this review we focus on TRPM7 and its association with growth factors, RTKs, and downstream kinase signaling. We also highlight how interplay between TRPM7, Mg2+ and signaling kinases influences cell function in physiological and pathological conditions, such as cancer and preeclampsia.

Frequency diversity signal is a kind of pulse signal with multiple frequency which has high anti-interference performance, and is commonly used in target detection, localization and radio communication by detecting the characteristics in the signal. This paper focus on detecting the frequency characteristic which has its distinct advantages compared with other characteristics. At present, time-frequncy analysis is the most commonly used method. Short-time Fourier transform (STFT) is one of them, however, it is not adaptive to the low SNR. Therefore, this paper makes improvement on the basis of traditionl STFT according to the problem and proposes an novel algorithm for extracting the frequency characteristic of frequency diversity signal. The algorithm combines STFT with the false alarm and detection probability, which can make full use of the information in frequency-domain. And the accuracy of detecting the frequency could reach 95% under-25dB.