Search

The hydrophobicity of ultrafiltration membranes is the main cause of membrane fouling and reduced permeability, so it is necessary to improve the hydrophilicity and anti-fouling performance of ultrafiltration membrane materials. MoS2 nanoparticles that were modified with polydopamine (PDA) and polyethyleneimine (PEI), named MoS2-PDA-PEI, were added to fabricate a polyethersulfone ultrafiltration membrane (PES/MoS2-PDA-PEI) for the first time. The effects of modified MoS2 nanoparticles on membrane performance were clarified. The results indicated that the permeability, rejection, and anti-fouling capability of the hybrid PES/MoS2-PDA-PEI membrane have been improved compared with the pristine PES membrane. When the content of MoS2-PDA-PEI nanoparticles in the membrane is 0.5%, the pure water flux of the hybrid membrane reaches 364.03 L m−2 h−1, and the rejection rate of bovine serum albumin (BSA) and humic acid (HA) is 96.5% and 93.2% respectively. The flux recovery rate of HA reached 97.06%. As expected, the addition of MoS2-PDA-PEI nanoparticles promotes the formation of the porous structure and improves the hydrophilicity of the membrane, thereby improving its antifouling performance.

Parkinson's disease (PD) is a neurodegenerative disorder, which is characterized by microglia activation and dopaminergic neurons affected by inflammatory processes. Inflammation has been recognized to be necessary for initiation and progress of PD. Emerging evidence indicates that NLRP3 inflammasome complex is involved in the recognition and execution of host inflammatory response. Stress is acknowledged to be a predisposing and precipitating factor in some neurodegenerative diseases. However, it is unknown whether chronic unpredictable mild stress (CUMS) sensitized microglia to pro-inflammatory stimuli. In this study, in vivo experiments are used to evaluate the effects of CUMS on lipopolysaccharide (LPS)-induced microglia activation and NLRP3 inflammasome activation. The results showed that CUMS pretreatment for 14 days significantly aggravated the behavioral dysfunction of PD rats, increased the activation of microglia. Pretreatment with CUMS for 14 days increased the levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-a (TNF-a) in the serum, and increased the expression of NLRP-3, ASC, Casepase-1 in the substantia nigra of PD rats. Our data showed that pretreatment with CUMS for 14 days increased the microglia activation and the DA neurons damage, and the mechanisms may be associated with the acceleration of the inflammatory response and activation of NLRP3 inflammasome.

Biotic and abiotic stresses, especially heavy metal toxicity, are becoming a big problem in agriculture, which pose serious threats to crop production. Plant hormones have recently been used to develop stress tolerance in a variety of plants. Brassinosteroids (BRs) are the sixth class of plant steroid hormones, with pleiotropic effects on plants. Exogenous application of BRs to boost plant tolerance mechanisms to various stresses has been a major research focus. Numerous studies have revealed the role of these steroidal hormones in the up-regulation of stress-related resistance genes, as well as their interactions with other metabolic pathways. BRs interact with other phytohormones such as auxin, cytokinin, ethylene, gibberellin, jasmonic acid, abscisic acid, salicylic acid, and polyamines to regulate a variety of physiological and developmental processes in plants. BRs regulate expressions of many BR-inducible genes by activating the brassinazole-resistant 1 (BZR1)/BRI1-EMS suppressor 1 (BES1) complex. Moreover, to improve plant development under a variety of stresses, BRs regulate antioxidant enzyme activity, chlorophyll concentration, photosynthetic capability, and glucose metabolism. This review will provide insights into the mechanistic role and actions of brassinosteroids in plants in response to various stresses.

Innovative syntheses of uniform and size-controlled chlorapatite crystals need to be developed. Molten salt synthesis is a simple process, which uses low temperatures and short reaction times to obtain synthesized powders with uniform chemical composition as well as good crystal morphology and high-phase purity. In this study, a molten salt synthesis was used to prepare ClAP microcrystallites at different temperatures, reaction times, and quantities of molten salt. ClAP microcrystallites with different sizes and morphologies were obtained, and the process parameters were optimized. The phase formation and morphologies of the ClAP microcrystallites were examined by X-ray powder diffraction and scanning electron microscopy. The results determined the optimal parameters, as follows: synthesis temperature, 600 °C; reaction time, 4 h; and ClAP/molten salt ratio, 1 : 3. The reaction time and the quantity of the molten salt, as well as the growth mechanism of the ClAP microcrystallites, were proposed based on the phase formation and morphologies of ClAP synthesized at various temperatures. ClAP phosphors activated using different ions (Sb3+, Eu2+, and Tb3+) were prepared by the molten salt method at 600 °C for 4 h with a ClAP/salt ratio of 1 : 3. The as-prepared ClAP:Sb3+/Eu2+/Tb3+ phosphors exhibited a blue-green emission (470 nm), a blue emission (460 nm), and a green emission (547 nm). Their excellent photoluminescence properties indicated their potential for application in white light emitting diodes.

Sensitive and selective detection of harmful gas is an important task in environmental monitoring. In this work, a gas sensor based on cataluminescence (CTL) for detection of acetaldehyde was designed by using nano-NiO as the sensing material. The sensor shows sensitive response to acetaldehyde at a relatively low working temperature of 200 &deg, C. The linear range of CTL intensity versus acetaldehyde concentration is 0.02&ndash, 2.5 mg/L, with a limit of detection of 0.006 mg/L at a signal-to-noise ratio of three. Mechanism study shows that electronically excited CO2 is the excited intermediate for CTL emission during the catalytic oxidation of acetaldehyde on the NiO surface. The proposed sensor has promising application in monitoring acetaldehyde in residential buildings and in the workplace.

The Zn1–xAl2O4:xEu2+ phosphor powders were synthesized by the solid-state reaction method. The synthesis temperature for ZnAl2O4 was optimized, whereas the phase structure, TEM images, photoluminescence (PL) properties, the concentration quenching mechanism, the fluorescence decay curves, as well as the CIE chromaticity coordinates of the samples were investigated in details. Under the excitation at 379 nm, the phosphor exhibits an asymmetric broad-band green emission with a peak at 532 nm, which is ascribed to the 5d–4f transition of Eu2+. When the doping concentration of Eu2+ ions is 0.01, the luminescence intensity of the sample reaches the maximum value. It is further proved that the exchange interaction results in the concentration quenching of Eu2+ in the Zn1–xAl2O4:xEu2+ phosphor powders. The thermal quenching property of ZnAl2O4:Eu2+ phosphor was investigated and the quantum efficiency (QE) values of the selected Zn0.99Al2O4:0.01Eu2+ phosphor was measured and determined as 54.85%. The lifetime of the optimized sample Zn0.99Al2O4:0.01Eu2+ is 3.0852 μs and the CIE coordinate of the sample was calculated as (0.3323, 0.5538) with high-color-purity green emission. All properties indicate that the green-emitting ZnAl2O4:Eu2+ phosphor powder has potential application in white LEDs.

A mercury(II) ion-selective electrode with an ionic liquid (IL), 1-methyl-2-butylthioimidazolium bis(trifluoromethanesulphonyl)imide ([C1C4Sim]NTf2) as active material was constructed. Parameters affecting the performance of the electrodes such as the dosages of the IL and carbon nanotubes and the aqueous pH values were investigated. Experimental results indicated that the optimal composition of the electrode filling material was 47.6% [C1C4Sim]NTf2, 47.6% tetrabutylphosphonium bis(trifluoromethanesulphonyl)imide (TBPNTf2) and 4.8% carboxylic multi-walled carbon nanotubes (MWCNTs-COOH). Under the selected conditions, the proposed electrodes showed a good linear response in the concentration range of 10−10–10−5 mol L−1 and had a detection limit of 4.1 × 10−11 mol L−1. No great interference from common metal ions was found. The proposed electrodes were applied to determine Hg2+ in seafood samples; the results were comparable to those of the direct mercury analyzer. Keywords: Ionic liquids (ILs), Mercury, Ion-selective electrodes, Carbon nanotubes, Seafood

Influence of floc breakage and re-growth on the release of natural dissolved organic matter (DOM) and dissolved Al was explored. Results indicated that Al species including monomeric species (Ala), medium polymer species (Alb), and colloidal or solid species (Alc) in polyaluminum chlorides (PACls) played significant role. At lower doses ranged from 5 to 20 mg/L, floc breakage damaged Ala-NOM bonds for AlCl3, causing obvious release of DOM and dissolved Al. After re-growth, dissolved Al mainly connected with broken flocs, rather than released DOM. Thus, after re-growth, DOM release was still remarkable, but additional removal of dissolved Al was observed. At higher doses above 20 mg/L, more Ala transformed to Alb and Alc. Due to the enmeshment effect induced by Alc coagulation, fewer DOM and dissolved Al were released after breakage, and additional removal of DOM and dissolved Al were attained after re-growth. For PAClAl13 which mainly contained Alb, at optimal dose, floc breakage generated the most severe release of DOM and dissolved Al, while the result after re-growth was just reverse. This was ascribed to stronger charge neutralization ability of Alb. Furthermore, the influence of floc breakage and re-growth on DOM and dissolved Al for PAClC was similar to that for AlCl3. The reason was fully analyzed in this research. This study may give further indication regarding reaction mechanisms of floc breakage and re-growth for PACls.

As one of the most complicated joint structures, temporomandibular joint (TMJ) is susceptible to inflammatory reaction caused by osteoarthritis, rheumatoid arthritis and so on. The treatment for TMJ inflammation is still challenging due to the rapid clearance and lack of selectivity of traditional medication. Herein, we design a novel discrete sulfonylcalix[4]arene-based magnesium(II) coordination container, MgDHIA, which features satisfactory biocompatibility, appropriate molecular size and multiple binding domains. MgDHIA is capable of selectively encapsulating rapamycin (RAPA) in the endo cavity and folic acid (FA) in the exo cavities to form the co-loaded system RAPA-FA@MgDHIA, which exhibits outstanding activated macrophages targeting, stepwise releasing and cellular uptake behaviors. For therapeutic aspect, the RAPA-FA@MgDHIA reprograms the phenotype of polarized macrophages, specifically, transforming the pro-inflammatory M1 macrophages to anti-inflammatory M2 phenotype by inhibiting NF-kB pathway. The in vivo studies also demonstrate that the RAPA-FA@MgDHIA presents higher accumulation in inflamed synovial tissues, protecting the articular cartilage and subchondral bone structures by alleviating synovial inflammation. Anyway, we first evaluate the application of coordination container-based nanomedicine in treatment of inflammatory TMJ, demonstrating that the drug and targeting agents co-loaded coordination container remarkably boosts the therapeutic efficacy of traditional medication, thus providing a promising approach for anti-inflammatory treatment in joints.

In this work, the treatment of bio-treated coking wastewater (BCW) by catalytic ozonation was conducted in semi-batch and continuous flow reactors. The kinetics of chemical oxygen demand (COD) removal were analyzed using BCWs from five coking plants. An integral reactor with catalytic ozonation stacked by ozone absorption (IR) was developed, and its efficiency was studied. The catalyst of MnxCe1-xO2/&gamma, Al2O3 was efficient in the catalytic ozonation process for the treatment of various BCWs. The chemical oxygen demand (COD) removal efficiencies after 120 min reaction were 64&ndash, 74%. The overall apparent reaction rate constants were 0.0101&ndash, 0.0117 min&minus, 1, which has no obvious relationship with the initial COD of BCW and pre-treatment biological process. The IR demonstrated the highest efficiency due to the enhancement of mass transfer and the utilization efficiency of ozone. Bypass internal circulation can further improve the reactor efficiency. The optimal results were obtained with the ozone absorption section accounting for 19% of the valid water depth in the reactor and 250% of circulation flow ratio. The long-term and full-scale application of the novel reactor in a continuous mode indicated stable removal of COD and polycyclic aromatic hydrocarbons (PAHs). The results showed that the system of IR is a promising reactor type for tertiary treatment of coking wastewater by catalytic ozonation.

In this study, the performance of catalytic ozonation in the treatment of bio-treated coking wastewater (BCW) using pilot- and full-scale systems was investigated. Additionally, the removal efficiency of organic pollutants from BCW, the deactivation mechanism of MnxCe1-xO2/γ-Al2O3, and backflushing optimization for in-situ catalyst regeneration, which have not been previously investigated, were analysed. Results of the 12-month pilot scale experiments showed that catalytic ozonation resulted in the effective removal of organic pollutants when backflushing was applied as an in-situ catalyst regeneration strategy. The effluent chemical oxygen demand (COD) content decreased from 150 to 78 mg L−1, and remained below a discharge limitation of 80 mg L−1, and the stable COD removal efficiencies (from 56.0% to 47.9%) indicated that catalyst deactivation, which primarily resulted from the deposition of inorganic salts on the surface of the catalyst that limited interaction between ozone and active sites and/or prevented electrons transfer, was primarily inhibited by backflushing. The catalyst regeneration via in-situ air- and water-backflushing was attributed to the scrubbing, collision, and/or the loosing effect. Additionally, in the full-scale experiment, the catalytic ozonation process with in-situ alternative backflushing exhibited a stable COD removal efficiency (above 45.6%) for 885 days when water- and air-flushing strengths of 10 L m−2 s−1 and 15 L m−2 s−1, respectively, were applied with a 7-day regeneration interval. Therefore, the results of this study provide new insights into catalytic ozonation and support its engineering application in BCW treatment.

Associations between vitamin D receptor (VDR) gene polymorphisms and allergic diseases were already reported by many publications. The aim of this meta-analysis was to clarify associations between VDR gene polymorphisms and allergic diseases by combing the results of all relevant publications. Eligible publications were searched from Pubmed, Embase, WOS and CNKI. We used Review Manager to combine the results of individual studies. Twenty-one studies were included in this study. Combined results proved that VDR rs1544410 BsmI (over-dominant comparison: p = .04, OR = 1.14, 95% CI 1.01–1.29; allele comparison: p = .03, OR = 1.11, 95% CI 1.01–1.22) and rs731236 TaqI (dominant comparison: p = .01, OR = 1.18, 95% CI 1.04–1.33) polymorphisms were both associated with allergic diseases. In subgroup analyses by type of disease, we confirmed positive results for rs1544410 BsmI polymorphism in both asthma and atopic dermatitis, and for rs731236 TaqI polymorphism in atopic dermatitis. Besides, in subgroup by ethnicity of participants, we observed significant associations with allergic diseases for rs7975232 ApaI polymorphism in Caucasians, for rs1544410 BsmI polymorphism in Asians and Caucasians, and for rs731236 TaqI polymorphism in Asians. We also investigated associations between VDR rs2228570 FokI polymorphism and allergic diseases, yet no any positive results were detected for this polymorphism. If we only focused on asthma, then positive findings were detected for rs1544410 BsmI polymorphism in Caucasians, and for rs731236 TaqI polymorphism in Asians. Collectively, this meta-analysis proved that VDR rs7975232 ApaI, rs1544410 BsmI and rs731236 TaqI gene polymorphisms may confer susceptibility to allergic diseases in certain populations.

Parkinson's disease (PD) is the second most common neurodegenerative disease, which is characterized by loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc). Accumulated evidences have suggested that oxidative stress is closely associated with the dopaminergic neurodegeneration of PD that can be protected by antioxidants. Biochanin A that is an O-methylated isoflavone in chickpea is investigated to explore its protective mechanism on dopaminergic neurons of the unilateral lipopolysaccharide (LPS)-injected rat. The results showed that biochanin A significantly improved the animal model's behavioral symptoms, prevented the loss of dopaminergic neurons and inhibited the deleterious microglia activation in the LPS-induced rats. Moreover, biochanin A inhibited nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase) activation and malondialdehyde (MDA) production, increased superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities in the rat brain. These results suggested that biochanin A might be a natural candidate with protective properties on dopaminergic neurons against the PD.

The reuse of produced water generated by natural gas extraction from Marcellus Shale for hydraulic fracturing is the dominant management option in Pennsylvania (PA), USA. The advantages and disadvantages of this management approach are reviewed and discussed together with long-term concerns and technology development needs. Abandoned mine drainage is a promising alternative make-up water, but high sulfate concentrations will lead to barite precipitation once it is mixed with the produced water. Bench-scale studies were conducted to optimize barite separation from this mixture that meets the finished water quality criteria for sulfate. Conventional separation processes are very effective in removing these solids but radium (Ra) co-precipitation may be a concern for their disposal in municipal landfills. If the produced water volume exceeds the reuse capacity for hydraulic fracturing, lime–soda ash softening can be used to remove divalent cations, including radium, to enable the production of pure salts using subsequent thermal processes.

Flowback water generated during unconventional gas extraction is of great concern due to its high total dissolved solids (TDS), radioactive elements and organic matter. Abandoned mine drainage (AMD) is a water source that is often located in the vicinity of gas wells and can be mixed with flowback water to reduce fresh water usage for hydraulic fracturing. The feasibility of microfiltration to separate solids created by mixing actual flowback water and AMD was evaluated using a bench-scale setup. Hydrophilic polyvinyldiene fluoride (PVDF) membrane with a pore size of 0.22 μm was as a model polymeric microfiltration membrane. Severe membrane fouling occurred during the first 5 min of filtration with one flowback/AMD mixture while no significant fouling was observed for a different mixture. It was found that the flowback water that caused membrane fouling contained stable iron-based colloids with an average particles size of 0.2 μm, especially in the samples collected early in the flowback period. These colloids were not formed by mixing flowback water containing high barium concentration with AMD rich in sulfate but were originally present in the flowback water. Stability of these sub-micron colloidal particles at high ionic strength of the flowback water is attributed to organic coating on the particle surface.

Acid-washed activated carbon (AC-A), nitric acid modified activated carbon (AC-NO2), aminated activated carbon (AC-NH2) and cerium-loaded activated carbon (Ce/AC) were prepared and characterized by BET procedure, Boehm titration and SEM. Their performances were investigated for the ozonation of p-chlorobenzoic acid (p-CBA) in its solution and organic compounds in reverse osmosis concentrate (ROC). Nitration and amination had little effect on the surface area of catalyst, but increased the concentration of surface acid and basic functional group respectively. After loading Ce, the surface area of the catalyst decreased, and amount of Ce particles were agglomerated on the surface of activated carbon. All the four catalysts can improve the removal rate of the organics in water. Among the four catalysts, Ce/AC shows the highest catalytic activity. The removal rates of p-CBA, TOC and three target pollutants (e.g., tetracycline, metoprolol, atrazine) are 99.6%, 70.38%, 97.76%, 96.21% and 96.03%, respectively. Hydroxyl radical (&middot, OH) was proved to be the core of catalytic reaction mechanism for Ce/AC, with the contribution rate to p-CBA removal of 91.4%. The surface groups and the Ce loaded on AC were the initiator for the rapid generation of &middot, OH. Electron transfer between electron-rich structures and cerium oxide might be a synergistic effect that can increase catalytic activity of Ce loaded on AC. Catalytic ozonation with Ce/AC is a promising ROC treatment technology due to its efficiency and possibilities for improvement.

Rare earth aluminate phosphors are well-known for being nontoxic and environmentally friendly. In this work, Tb3+-doped SrLaAlO4 phosphors were synthesized via a facile high temperature solid-state reaction method. The Optimum reaction temperature is determined to be 1300 °C based on the results of powder X-ray diffraction (XRD). The SEM patterns and TEM images correspond with the results of Rietveld refinement and show that the SrLa1-xAlO4:xTb3+ samples present a flaky structure. The results of photoluminescence spectrums (PL) show that SrLa1-xAlO4:xTb3+ phosphors can absorb in the UV–vis spectral region of 228 nm–263 nm and exhibit several emission peaks between 450 and 650 nm, and the highest peak was at 508 nm. The luminescence properties of SrLa1-xAlO4:xTb3+ have a strict dependence on the cation substitution levels. When the doping concentration of Tb3+ was 0.05, the emission intensity of the sample is strongest. The thermal quenching result of the SrLa0.95AlO4:0.05 Tb3+ phosphors shows that these phosphors are relatively sensitive to temperature changes under an excitation of 228 nm, as the temperature increases from 25 °C to 125 °C, the emission intensity (peak at 548 nm) decayed to 55.11% of that at room temperature. However, when the temperature increases to 125 °C, the emission intensity (peak at 548 nm) decayed to 61.16% of the initial value under an excitation of 263 nm, which showed a relatively good thermal stability. The internal quantum efficiency (QE) values of the SrLa0.95AlO4:0.05 Tb3+ phosphors was measured and determined to be 48%. Under excitations of 228 nm and 263 nm, the lifetimes of the optimized sample SrLa0.95AlO4:0.05 Tb3+ were 1.3986 ms and 1.2095 ms, respectively, and the CIE coordinates of the sample were calculated as (0.2971, 0.4981), (0.3056, 0.5329), respectively. Under both excitations SrLa0.95AlO4:0.05 Tb3+ exhibited high-color-purity green emission.

A new column loaded with modified silica gel-chitosan is proposed as a preconcentration system for adsorption of trace cadmium (II) and copper (II). The optimization steps were performed under dynamic conditions, involving pH, sample flow rate, eluent selection, concentration, volume, and flow rate. Trace Cd(II) and Cu(II) were quantitatively adsorbed by the modified silica gel-chitosan. The metal ions adsorbed on the separation column were eluted with 0.1 M HNO3 and determined by flame atomic absorption spectrometry. Under the optimum conditions, this method allowed the determination of cadmium and copper with limits of detection (LOD) of 20 ng L−1 and 38 ng L−1, respectively. The relative standard deviation values (RSDs) for 1.0 mg L−1 of cadmium and 1.0 mg L−1 of copper were 2.62% and 2.85%, respectively.

Formation of mineral scales in industrial and municipal systems causes service interruption, performance decline, and often a complete system failure. Control of mineral scales may include costly water purification to remove scale-forming components or a simple addition of antiscaling chemicals. Although the use of antiscalants has very long history, it still relies more on experience and empirical solutions than on fundamental understanding of mechanisms by which these chemicals can reduce or prevent scale formation. Challenges for scale control include fairly complex interactions in aqueous systems, changing water chemistry, pH and temperature changes, and application of corrosion and biofouling strategies that could compromise the effectiveness of antiscalants. It is generally accepted that antiscalants do not completely eliminate scaling tendency but can inhibit the nucleation and/or crystallization phases. The main mechanisms by which antiscalants can control the formation of mineral precipitates include threshold inhibition, crystal modification, sequestration (chelation), or dispersion. It is desirable to utilize antiscalants that rely on more than one mechanism to ensure reliable performance. The dominant classes of antiscaling chemicals nowadays include polyphosphates, organophosphonates, and various polyelectrolytes. Depending on the application in question, there are several experimental approaches that may be utilized to evaluate the optimal control strategy that is compatible with other goals of water treatment. They range from simple beaker tests to recirculating systems with and without heated surfaces, electrochemical impedance spectroscopy, and dynamic tube blocking experiments for high pressure and temperature applications. It is important to note that these experimental systems are effective in demonstrating relative performance of different antiscaling approaches but that the final adjustments have to be performed during field applications. Case studies discussed in this chapter include the application of specific chemicals for the control of mineral scales in cooling systems using secondary-treated municipal wastewater, scaling control in reverse osmosis desalination, and inhibition of barium sulfate scaling on the production casing during unconventional shale gas extraction.

Inflammation in the brain, characterized by the activation of microglia, is believed to participate in the patho- genesis of Parkinson's disease. Biochanin A, an O-methylated isoflavone, is a natural organic compound and is classified as a phytoestrogen. In this study, using murine BV2 microg- lial cells, we investigated the anti-inflammatory effects of biochanin A and the possible mechanisms involved. BV2 microglial cells were treated with lipopolysaccharide (LPS) to induce pro-inflammatory responses and the cells were then treated with biochanin A. Cell viability was examined by MTT assay. The production of nitric oxide (NO) was examined using Griess reagent and intracellular reactive oxygen species (ROS production) was measured by DCFH-DA assay. The mRNA expression of interleukin-1β (IL-1β), inducible nitric oxide synthase (iNOS) and tumor necrosis factor-α (TNF-α) was examined by RT-PCR. The expression of p-ERK, p-JNK, p-p38 and iNOS was measured by western blot analysis. In addition, the protein and mRNA and phosphorylation levels of pro-inflammatory cytokines were determined by western blot analysis and RT-PCR, respectively. The results revealed that biochanin A attenuated LPS-induced microglial activation and the production of TNF-α, IL-1β, nitric oxide and reactive oxygen species in a dose-dependent manner. Biochanin A significantly decreased the LPS-induced mRNA expression of TNF-α and IL-1β, and inhibited iNOS mRNA and protein expression. Furthermore, biochanin A significantly inhibited the LPS-induced phosphorylation of c-Jun NH2-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and p38. These findings suggest that the inhibitory effects of biochanin A on LPS-induced proinflammatory responses may be associated with the inhibition of mitogen-activated protein kinase (MAPK) signaling pathways in BV2 microglial cells.

Flowback water from natural gas extraction in Marcellus Shale contains very high concentrations of inorganic salts and organic chemicals. Potential reuse of this water in subsequent hydraulic-fracturing operations may be limited by high concentrations of divalent cations (e.g., Ba, Sr, and Ca). Kinetics of barite and celestite precipitation in flowback waters from different well sites was evaluated in this study. Ba reacted rapidly with sulfate and reached equilibrium within 30 min, whereas Sr reacted slowly and took days to reach equilibrium. Equilibrium concentrations of Ba and Sr predicted by thermodynamics models were compared with experimental results. Activity corrections based on the Pitzer equation provided the best agreement with experimental data for both Ba and Sr. Comparison of barite and celestite precipitation kinetics in actual and synthetic flowback water revealed that there was no observable impact of organics and other minor components in actual flowback water on barite precipita...

The kinetics for complete iron release showing biphasic behavior from pig spleen ferritin-Fe (PSFF) was measured by spectrophotometry. The native core within the PSFF shell consisted of 1682 hydroxide Fe3+ and 13 phosphate molecules. Inhibition kinetics for complete iron release was measure by differential spectrophotometry in the presence of phosphate; the process was clearly divided into two phases involving a first-order reaction at an increasing rate of 46.5 Fe3+/PSFF/min on the surface of the iron core and a zero-order reaction at a decreasing rate of 6.67 Fe3+/PSFF/min inside the core. The kinetic equation [C(PSFF-Fe3+)max - C(PSFF-Fe3+)t](1/2) = Tmax - Tt gives the transition time between the two rates and represents the complex kinetic characteristics. The rate was directly accelerated twofold by a mixed reducer of dithionite and ascorbic acid. These results suggest that the channel of the PSFF shell may carry out multiple functions for iron metabolism and storage and that the phosphate strongly affects the rate of iron release.

Bacterial ferritin of Azotobacter vinelandii (AvBF) is directly able to pick electrons up for iron release from or transfer them for storage to a platinum electrode in the absence of mediator or other reducer. The ferritin containing the structure of heme-Co2+ in part shows weakened activity to electrode and decreases the rate of iron release greatly. A reversible reduction process of the ferritin is observed by the spectral change regularly ranging from 310 to 260 nm under mixed gases containing 98% H2 and 2% to O2. The activity of nitrogen fixation from the whole cell of A. vinelandii increases greatly by H2 reduction with potentials ranging from -397 to -425 mV vs. NHE, indicating two important roles of H2-uptake reaction of the ferritin in increasing activity of nitrogen fixation and in supplying iron to synthesize nitrogenase.

Acremoniumterricola milleretal mycelium (AMM) exerts numerous protective effects on organs, and has been used in Chinese herb prescriptions to treat refractory diseases. The aim of this study was to investigate the effects of AMM on immunological hepatic fibrosis induced by porcine serum (PS) in rats. Male Sprague Dawley rats were administered 0.5 ml sterile PS by intraperitoneal injections twice a week for 18 weeks. AMM (175, 350 or 700 mg/kg) and colchicine (0.1 mg/kg) were administered intragastrically each day until the rats were sacrificed. PS administration resulted in marked hepatic fibrosis, as assessed by increased oxidative stress and hepatic collagen content, as well as α‑smooth muscle actin (α‑SMA) expression. AMM significantly reduced liver damage and fibrosis. In addition, AMM decreased the elevation in hydroxyproline, hyaluronic acid, laminin and procollagen type III; increased the activity of superoxide dismutase and glutathione peroxidase; decreased α‑SMA expression; and eliminated hepatic collagen deposits. Furthermore, AMM inhibited Smad2/3 phosphorylation and Smad7 expression. These results indicate that AMM is able to reduce oxidative stress, inhibit collagen synthesis and block the transforming growth factor‑β/Smad signaling pathway in a dose‑dependent manner.

In bioelectrochemical studies, redox mediators such as methylene blue, natural red, and thionine are used to studying the redox characteristics of enzymes in the living cell. Here we show that nitrogenase activity in Azotobacter vinelandii is completely inhibited by oxidized methylene blue (MBo) when the concentration of this mediator in the medium is increased up to 72 microM. This activity in A. vinelandii is somewhat inhibited by a coenzyme, ascorbic acid (AA). However, the nitrogenase activity within the A. vinelandii cell is unchanged even for a high concentration of oxidized natural red (NRo) alone. Interestingly, these mediators and AA do not have the capacity to inhibit the H2 uptake activity of the hydrogenase in A. vinelandii. Average active rates of 66 nM H2 evolved/mg cell protein/min from the nitrogenase and 160 nM H2-uptake/mg cell protein/min from the hydrogenase in A. vinelandii are found in aid of the activities of the enzymes for H2 evolution and for H2 uptake are compared. The activities of both enzymes in A. vinelandii are strongly inhibited by thionine having high oxidative potential. Mechanisms of various mediators acting in vivo for both enzymes in A. vinelandii are discussed.