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Photocatalytic CO2 reduction is a highly vital process for converting CO2 into valuable chemicals. However, the reaction always proceeds less efficaciously at low temperature. A combination of optical and thermal conditions is one of the feasible approaches to achieve the reaction with high efficiency and has gained much attention recently. In the present work, we prepared several Co–Cu–Mn trimetallic catalysts via a simple co-precipitation method, which were used in catalyzing photothermal CO2 reduction to hydrocarbons. The metal composition and reduction temperature of the catalysts had important effects on their structural and photoelectrical characteristics and adsorption behaviors, further resulting in diverse catalytic performances. Among the prepared trimetallic catalysts, Co7Cu1Mn1Ox(200), with a Co/Cu/Mn molar ratio of 7/1/1 and reduced at 200 °C in H2 for 2 h, could produce CH4 with an activity of 14.5 mmol gcat−1 h−1 in 10% CO2/30% H2/60% N2, and CH4 and C2+ hydrocarbons with the activities of 15.9 and 7.5 mmol gcat−1 h−1 in 25% CO2/75% H2, respectively. The present strategy for constructing trimetallic oxide catalysts for the photothermal reaction not only provides a highly active catalyst for CO2 utilization, but also offers a potential possibility for reducing the high temperature of conventional thermal reactions.

The rapid consumption of conventional fossil fuels has caused a sharp decline in their reserves and led to climate change. Exploitation of renewable energy sources especially bio-fuels such as 2,5-dimethylfuran (DMF), methylfuran (MF), γ-valerolactone (GVL), etc. has both environmental and economic benefits. In the present work, diverse Co-based bimetallic catalysts were prepared and used for catalyzing hydrodeoxygenation (HDO) of biomass-derived oxygenates. Co5Zn1Ox, obtained by the incorporation of Zn species into the Co metal catalyst especially with a Co/Zn molar ratio of 5, could enhance the catalytic performances obviously compared to the sole Co catalyst. For example, the DMF, MF, and GVL yields reached up to 94, 98, and 77% during the catalysis by Co5Zn1Ox, which were much greater than 74, 0, and 23% for the Co catalyst, respectively. The enhanced performances of Co5Zn1Ox stem from the strong interaction between the Co and Zn species. Specifically, the presence of ZnO could stabilize Co2+ species, by offering electrons to Co species and creating oxygen vacancies, resulting in Co5Zn1Ox showing the highest adsorption amounts of furfural and furfuryl alcohol compared to Co1Zn1Ox and Co7Zn1Ox catalysts. Moreover, the catalyst showed good universality and reusability, and the HDO of 5-HMF to DMF proceeded in a true heterogeneous manner. The present work is believed to extend the application of bimetallic catalysts to the synthesis of bio-fuels and utilization of biomass materials.

Exposure of tumor cells to ionizing radiation (IR) alters the microenvironment, particularly the fatty acid (FA) profile and activity. Moreover, abnormal FA metabolism, either catabolism or anabolism, is essential for synthesizing biological membranes and delivering molecular signals to induce ferroptotic cell death. The current review focuses on the bistable regulation characteristics of FA metabolism and explains how FA catabolism and anabolism pathway crosstalk harmonize different ionizing radiation-regulated ferroptosis responses, resulting in pivotal cell fate decisions. In summary, targeting key molecules involved in lipid metabolism and ferroptosis may amplify the tumor response to IR.

High-density lipoprotein (HDL) confers protection against cardiovascular disease partly attributable to its robust anti-oxidant activities, which is largely impaired in diabetic conditions. In this study, we analyzed the anti-oxidant activity of HDL, as represented by the arylesterase activity of paraoxonase 1 (PON1) in HDL particles, in 216 consecutive HF patients with (n = 79) or without (n = 137) type 2 diabetes, and age- and gender-matched 112 diabetic and 189 non-diabetic non-HF controls. We found arylesterase activity was significantly decreased in patients with than without HF, and was further decreased when comorbid with diabetes. After adjusting for conventional risk factors and apolipoprotein A-I levels, arylesterase activity remained correlated positively with left ventricular ejection fraction in diabetic (r = 0.325, P = 0.020) but not non-diabetic patients (r = 0.089, P = 0.415), and negatively with NT-proBNP and NYHA functional class in both subgroups. In regression analyses, a higher risk of HF was observed in diabetic than non-diabetic patients when having low arylesterase activities. In conclusion, our data demonstrate that impaired serum arylesterase activity in patients with HF is further reduced when comorbid with diabetes. The relationship of impaired arylesterase activity to HF is especially enhanced in diabetic patients.

H-bond donor (HBD) and base co-catalysis achieved great success in ring-opening polymerization (ROP). Parallel H-bond donor and Bronsted acid (HBD–BA) cocatalysis has been scarcely explored in ROPs. In developing the HBD–BA catalysis in to versatile toolbox for ring-opening polymerizations of wider scope and better control, tunable HBDs including boronate pinacol ester urea (BU), urea (U), and thiourea (TU) were evaluated in cooperation with trifluoroacetic acid (TFA) in HBD–BA catalytic mode. Each of the HBD–TFA co-catalyst promoted ROPs of δ-valerolactone (VL) and e-caprolactone (CL) successfully. The catalytic performances of the HBD–TFA on the HBD part was in an order of BU > U > TU to their corresponding ROPs of VL and CL. The turnover frequencies of the catalyzed ROPs of VL and CL by BU–TFA was twice as that of TFA. The ROPs afforded homopolymers with predicted molecular weights (PVL, Mn,NMR = 2.51–9.92 kg mol−1; PCL, Mn,NMR = 2.51–11.1 kg mol−1) and narrow dispersities (PVL, Đ ≤ 1.16; PCL, Đ ≤ 1.18) by ratios of monomer to initiator from 20 to 100. The obtained polymers were analyzed by 1H NMR, 13C NMR, and MALDI-ToF MS, the results indicated the high chain-end fidelity. Chain extension experiments were conducted by a first ROP of VL/CL and second ROP of CL/VL with precise molecular weights (from 2.98 kg mol−1 to 6.15 kg mol−1) and narrow dispersities below 1.18. The kinetics plots showed a distinct first order relationship between ln([VL]0/[VL]) versus the reaction time, it indicated the controlled nature of the catalytic ROP. NMR titrations supported the proposed mechanism that HBD associated with TFA and promoted the cationic polymerization.

Tall fescue [Schedonorus arundinaceus (Schreb) Dumort] has potential in cool arid regions, where it is often subject to salinity stress. The objective of this 2-year field study was to investigate the effect of nitrogen sources on tall fescue turf quality under salinity stress in the northern Great Plains of North America. ‘Wolfpack’, ‘Wolfpack II’, ‘Tar Heel’, ‘Tar Heel II’, ‘Jaguar 3’, ‘Jaguar 4G’, and ‘Arid 3’ were treated with NaCl and CaCl2 in equal amounts. Six N sources were used for fertilization: nitrate-N, urea-N, ammonium-N, urea-N/ammonium-N/nitrate-N, urea-N with urase and nitrification inhibitor, and organic N. Salt treatment reduced turf quality of all cultivars. Turf quality was affected differently by N source. Regardless of salt treatments, urea stabilized with a urease inhibitor and a nitrification inhibitor consistently had the best turf quality. Equal amounts of nitrate, ammonium, and urea-N yielded the lowest turf quality. However, there was no interaction between N source and salt treatment. These results were also supported by green density (GD), dark-green color index (DGCI), shoot chlorophyll (Chl) content, and leaf relative water content (RWC). Tall fescue cultivars responded to salinity treatment differently, with ‘Wolfpack II’ being the cultivar ranked consistently at the top and maintained above the acceptable level of visual quality.

A method for quantitative analysis of methotrexate (MTX) from formulated gels/creams and from tissue/solution samples after percutaneous permeation studies is described. High performance liquid chromatography (I-IPLC) with a MicroBondapak C18, reverse-phase column was used. A calibration curve of doses versus peak areas for MTX showed linearity over the range of 0.010-14.056 μg with a very high correlation coefficient (r) of 0.99998. Replicate analysis of μg of MTX showed that the peak area was 9627424±22111 counts (mean ± SD; one count is 1/8 μV-sec, 1μY is 2×10^(-6)a.u.) with a relative standard deviation of 0.23%. The resolution factor between MTX and folic acid was 33.35 when the applied doses of both were 1 μg each. Results demonstrated that the photolytic products of MTX, samples from gel and samples extracted from hairless guinea pig skin after percutaneous permeation and epidermis/dermis separation by microwave technique, could be well detected by this method. Preliminary results are satisfactory and meet the requirements of U.S. Pharmacopeia XXII. This report decribes novel approaches for determination of methotrexate content in the formulations and skin specimens. These approaches include the separation of epidermis and dermis by microwaving, the pretreatment procedures employed before analysis, and the use of guard column during HPLC analysis.

Typical organocatalyst promoted ring-opening polymerization (ROP) by activation of monomer or polymer chain end via the acidic or basic mechanism. Dual activating of both the monomer and the propagating polymer chain end suggested an ideal strategy of widely tuneable catalysis of high efficiency. Stoichiometric Bronsted acid–base adduct was rarely employed in ROPs since general Bronsted acid and Bronsted base quench each other. We proposed that an acid–base adduct may work bifunctionally in catalysis. The cationic part of the acid–base adduct as H-bond donor activated the monomer, and the counter anion part as H-bond acceptor activated initiator/chain end. A series of guanidiniums, derived from commercially available Bronsted acids and guanidine, were employed as catalysts in ROPs of carbonate, lactide, and lactone. Guanidinium triazabicyclodecene hydrochloride exhibited outstanding catalytic performances in the respect of the rate and controlled in the ROPs of l -lactide, trimethylene carbonate, and δ-valerolactone with nearly full conversions, predicted molecular weights, as well as narrow dispersity of Đ = 1.07. These experimental results indicated that guanidinium is an efficient organocatalyst in controlled/living ring-opening polymerization.

Catechol moiety offers a versatile platform in the preparation of functionalized polymers, but it is not usually compatible with catalysis in polymerizations. To address these challenges, we suggest employment of one Brønsted base in masking the activity of catechol moiety and to modulate the polymerization. Based on this strategy, the ring-opening polymerization (ROP) of sarcosine N-carboxyanhydrides (Sar-NCA) was carried out using dopamine hydrochloride as an initiator and triethylamine as a Brønsted base. PSar with predicted molecular weights (M n,NMR=3.7 kg mol−1) and narrow dispersities (ĐN-butyl glycine N-carboxyanhydrides (Bu-Gly-NCA) from the PSar in one-pot produced catechol end-functionalized amphiphilic polysarcosine-block-poly(N-butyl glycine) diblock copolypeptoids (cat-PSar-b-PGlyBu). Further, cat-PSar-b-PGlyBu enabled the aqueous dispersion of manganese oxide nanoparticles which was attributable to the anchor of the diblock copolymers onto the surface of the nanoparticles. The strategy for catechol masking and polymerization mediating by one Brønsted base offered a new avenue into the synthesis of catechol-ended block copolymers.

The copolymerization of structurally distinct epoxides and cyclic esters offers polyether-block-polyester copolymers which are valuable synthetic materials. However, the anionic ring-opening polymerization (ROP) of glycidyl ethers is not usually compatible with the subsequent ROP of lactide (LA). We designed a switchable approach composed of the tetrabutylammonium fluoride initiated ROP of glycidyl phenyl ether (GPE), followed by the addition of thiourea (TU) to initiate the ROP of LA. The active alkoxide chain end of the first ROP was turned into an alcohol, and the TU was turned into a thioureate anion (TUA). The TUA promoted the ROP of LA from the alcohol via bifunctional H-bonding catalysis to full monomer conversion in a controlled/living manner. Poly(GPE-b-LA) with precise molecular weights and narrow dispersities (Đ, 1.13 to 1.19) were prepared at room temperature in solution. 1H NMR titrations suggested the formation of the TUA and its coordination with chain end hydroxyl; this played key roles in the switch of ROPs and H-bonding catalyzed ROP of LA. The anionic to H-bonding switchable catalysis showed a general and simple protocol to copolymerize epoxides and cyclic esters into diblock copolymers.

Aliphatic polyesters are broadly used in biomedical materials, food packaging and drug delivery. The use of catalytic ring-opening polymerization (ROP) by dual catalysis, combining organocatalysis and metal complex catalysis, is a powerful strategy toward these valuable polyesters. In an endeavor to combine metal catalysis and organocatalysis in polymerization, we suggested the use of metal salts of an organophosphoric acid as bifunctional catalysts in the ROP of cyclic esters and of cyclic carbonates. Four metal organophosphates, viz. lithium, sodium, magnesium, and calcium diphenyl phosphates, were evaluated as catalysts for the ROPs of trimethylene carbonate (TMC), δ-valerolactone and lactide with 3-phenyl-1-propanol (PPA) as an initiator for obtaining aliphatic polyesters. Magnesium diphenyl phosphate (MgDP) showed relatively high catalytic activity and ideal control. The molecular weights of the PTMCs measured using 1H NMR matched well with the theoretical ones. 1H NMR, 13C NMR, and MALDI-ToF MS measurements demonstrated that the initiator and monomer polymerized quantitatively. Bulk polymerization with various [TMC]0/[PPA]0/[MgDP]0 ratios afforded PTMCs with expected molecular weights (Mn, NMR = 3.21–11.7 kg mol−1) and relatively narrow dispersities (Mw/Mn = 1.16–1.19). Kinetic studies, chain extension experiments and diblock copolymer synthesis were carried out to identify that the MgDP-catalyzed ROP proceeded in a controlled/living manner. A bifunctional catalytic mechanism for the MgDP catalyzed ROP was suggested from 1H NMR, 13C NMR and 31P NMR titration experiments. For evaluating the biosafety of the PTMC produced in the bulk ROP under MgDP catalysis, untreated PTMC samples were tested by an MTT assay using the L929 cell line. A result of more than 90% relative cell viabilities demonstrates the excellent cell compatibility of the PTMCs for potential biomedical applications.

The anionic ring-opening polymerizations (AROPs) of N-sulfonyl aziridines, in the presence of organic superbases including phosphazene (t-Bu-P4), Verkade’s base (P(i-PrNCH2CH2)3N, TiPP), DBU, MTBD, and N,N,N′,N′-tetramethylguanidine (TMG), using N-benzyl-p-toluenesulfonamide (BnN(H)Ts) as initiator were explored to produce metal-free poly(sulfonylaziridine)s. Among the superbases used, the catalytic activity was found directly proportional to their basicity. Remarkably, t-Bu-P4 and TiPP gave a living/controlled AROP of 2-methyl-N-tosylaziridine (TsMAz), where t-Bu-P4 performed better, affording the metal-free and well-defined poly(sulfonylaziridine)s with high molar masses (Mn(SEC) > 30 kg mol–1) and low dispersities (Đ 95%, 5 h). The organocatalyzed AROP allowed the use of lower catalyst (t-Bu-P4) l...

Experiments were carried out to study the dripping behavior of vertical burning thermally thin poly(methyl methacrylate) (PMMA) with different spacings between the wall and PMMA. The dripping behavior was studied by infrared video image analysis with spacings of 7, 10, 13, 16, 19, 22, and 25 mm. As the spacing increased, the dripping time and mass and burnout growth distance first increased and then decreased. The critical value was observed at the 13 mm case. The dripping behavior is assumed to correspond to the net heat flux to the surface, extensional viscosity, and gravitational force of melting PMMA. After the dripping, the pyrolysis and burnout spread rates become asymptotically equal. In this study, the effects of spacing between the wall and fuels on the dripping behavior were investigated for the first time using uniform PMMA samples with 200 mm height, 50 mm width, and 2 mm thickness.

Although detergent-based decellularization protocols have been widely used to obtain a natural extracellular matrix (ECM) scaffold in tissue engineering, some key challenges still exist. To achieve an optimum natural decellularized scaffold for the construction of tissue-engineered small-diameter blood vessels (TEBV), porcine carotid arteries (PCAs) were decellularized by combining sodium dodecyl sulfate (SDS), sodium deoxycholate (SDC) and Triton X-100 (Triton) in different concentrations. Tissue samples were processed and their histological, biochemical and biomechanical characteristics were investigated. Results showed that only two methods 0.5% (SDS + SDC) and 1% (SDS + SDC) could completely remove of the cellular contents and preserve the native ECM architecture. Furthermore, 1% (SDS + SDC) based methods acquire preferable porosity and suitable mechanical strength. Residual Triton in the ECM scaffold holds intensive cytotoxity. In conclusion, 1%(SDS + SDC) based method can obtain a superior PCAs scaffold for the construction of TEBV. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 619-631, 2018.

Graphene oxide (GO) was served as mechanical strengthening to prepare GO/Polyvinyl Alcohol(PVA) composite film. This was accomplished in order to explore the influence of contents of GO on the tensile strength and failure strain of GO/PVA composite film. The results showed that as the GO content increased, the tensile strength of the composite film became greater rapidly at first, and then decreased gradually. When the GO content was 20%, the film had its maximum tensile strength (59.6 MPa). This is over 500% of the tensile strength of pure PVA film. The failure strain of GO/PVA composite film decreased rapidly as the GO content increased. The enhancement mechanism of the composite can be explained by the existence of multi-hydrogen bonds between the hydroxyl (-OH) groups of PVA and oxygen-containing functional groups of GO.

Chronic alcohol consumption causes hippocampal neuronal impairment, which is associated with oxidative stress and apoptosis. Carvacrol is a major monoterpenic phenol found in essential oils from the family Labiatae and has antioxidative stress and antiapoptosis actions. However, the protective effects of carvacrol in ethanol-induced hippocampal neuronal impairment have not been fully understood. We explored the neuroprotective effects of carvacrol in vivo and in vitro. Male C57BL/6 mice were exposed to 35% ethanol for 4 weeks to establish ethanol model in vivo, and hippocampal neuron injury was simulated by 200 mM ethanol in vitro. Morris water maze test was performed to evaluate the cognitive dysfunction. The oxidative stress injury of hippocampal neurons was evaluated by measuring the levels of oxidative stress biomarkers. Histopathological examinations and western blot were performed to evaluate the apoptosis of neurons. The results showed that carvacrol attenuates the cognitive dysfunction, oxidative stress, and apoptosis of the mice treated with ethanol and decreases hippocampal neurons apoptosis induced by ethanol in vitro. In addition, western blot analysis revealed that carvacrol modulates the protein expression of Bcl-2, Bax, caspase-3, and p-ERK, without influence of p-JNK and p-p38. Our results suggest that carvacrol alleviates ethanol-mediated hippocampal neuronal impairment by antioxidative and antiapoptotic effects.

Aberrant changes in endothelial phenotype and morphology are considered to be initial events in the pathogenesis of atherosclerosis. Direct observation of the intact endothelium will provide valuable information for understanding the cellular and molecular events in the dysfunctional endothelial cells. Here, we describe a modified en face immunofluorescence staining technique which enables scientists to obtain clear images of the intact endothelial surface and analyze the molecule expression patterns in situ. The method is simple and reliable for observing the entire endothelial monolayer at different sites of the aorta. This technique may be a promising tool for understanding the pathophysiology of atherosclerosis, especially at an early stage.

N-heterocycles with quinoline and tetrahydroquinoline structures are highly important in pharmaceutical and chemical industries, and their highly efficient mutual transformations are vital but still challenging. In the present work, AlN supported redox cobalt catalysts (Co3O4/AlN and Co/AlN) were prepared, which could achieve the reversible aerobic oxidative dehydrogenation/hydrogenation of N-heterocycles with good performances. The catalytic performances were stem from the strong interaction between Co species with AlN support, which were confirmed by the characterizations of Raman, XPS, UV–vis DRS, and H2-TPR etc. Both of the catalysts showed good stabilities and reusabilities for the titled reactions. Besides, the gram-scale experiments achieved with good yields to corresponding products, revealing the present protocol possesses great potential applications in industry. The strategy of using redox Co-based catalyst not only provides a potential catalyst for the reversible hydrogenation/oxidative dehydrogenation reactions but also replenishes methods for constructing of other redox catalyst, especially with AlN as a carrier.

Ethnobotanical relevance Catalpol is the main active component of the radix from Rehmannia glutinosa Libosch, which has pleiotropic protective effects in neurodegenerative diseases, ischemic stroke, metabolic disorders and others Aim Catalpol has been shown to have neuroprotective, neurorepair, and angiogenesis effects following ischemic brain injury. However, its molecular mechanisms are still poorly understood. In previous studies, the JAK2/STAT3 signaling pathway was found to play a role in neuroprotection and angiogenesis. This study investigated the role of catalpol in stimulating angiogenesis via the JAK2/STAT3 pathway after permanent focal cerebral ischemia (pMCAO). Methods Rats were subjected to right middle cerebral artery occlusion through electrocoagulation and were treated with catalpol (5 mg/kg), AG490 was also used to inhibit STAT3 phosphorylation (pSTAT3). Results Following stroke, Catalpol improved the neuroethology deficit, increased the cerebral blood flow (CBF) of infarcted brain and upregulated EPO and EPOR. AG490 suppressed the phosphorylation of signal transducer and activator of transcription 3 (STAT3), ultimately inhibited VEGF mRNA expression, which reduced VEGF protein expression and inhibited stroke-induced angiogenesis. However, Catalpol enhanced stroke-induced STAT3 activation and subsequently restored STAT3 activity through the recovery of STAT3 binding to VEGF. Moreover, Catalpol reversed the effect of AG490 on STAT3 activation and nuclear translocation, restored the transcriptional activity of the VEGF promoter by recruiting STAT3 to the VEGF promoter, improved VEGF mRNA and protein expression, increased angiogenesis, reduced the difference in CBF between the infarcted and intact brain and ameliorated the neuroethology behaviors after stroke. Conclusion Catalpol affects neuroprotection and angiogenesis via the JAK2/STAT3 signaling pathway, which is mediated by STAT3 activation and VEGF expression. Catalpol may be used as a potential therapeutic drug for stroke.

Near infrared spectroscopy (NIR) was applied to discriminate the roots of salvia miltiorhiza Bunge (Danshen for short) and Salvia yunnanensis C. H. Wright (Zidanshen for short) by means of principal component analysis (PCA), improved and simplified K nearest neighbors (IS-KNN). Furthermore, an ultra-high performance liquid chromatographic (UHPLC) coupled with photodiode-array detector was developed for building fingerprints of lipophilic components of Danshen and Zidanshen, respectively. Basing on NIR information, both PCA and IS-KNN method classified the two kinds of Chinese medical herbs with 100% accuracy. The chromatographic fingerprints of the lipophilic components of Danshen and Zidanshen have 10 and 12 common peaks, respectively. Liquid chromatography coupled with mass spectroscopy (LC-MS-MS) was applied to identify these peaks. Among these, three small peaks in the fingerprints of Zidanshen are not found in Danshen, one of which was identified as α-lapachone, and the other two compounds were not yet identified; a small peak after tanshinone IIA in the fingerprints of Danshen was not found in Zidanshen, which was identified as miltirone. The two herbs have 10 common lipophilic components. The similarity between the two reference chromatograms of Zidanshen and Danshen is 0.902, but the mean similaritie between Zidanshen (or Danshen) fingerprints and its own reference chromatogram is 0.973 (or 0.976). The contents of main lipophilic components are significantly lower in Zidanshen than in Danshen (P 0.01 or P 0.05). The results indicate that the two Chinese medical materials are not only different in NIR spectra, but also different in species and quantities of lipophilic components. NIR spectra analysis can identify Danshen and Zidanshen rapidly and accurately. UHPLC coupled with MS analysis demonstrates the detail differences between the two herbs both in species and contents of their lipophilic components.

Increased transcytosis of low-density lipoprotein (LDL) across the endothelium and oxidation of LDL deposited within the subendothelial space are crucial early events in atherogenesis. C1q/TNF-related protein (CTRP) 5 is a novel secreted glycoprotein and its biological functions are largely undefined.Expression of CTRP5 was analyzed in sera and atherosclerotic plaques of patients with coronary artery disease (CAD). The role of CTRP5 in atherogenesis was investigated in vitro and in vivo.We found CTRP5 serum levels were higher in patients with than without CAD (247.26 ± 61.71 vs. 167.81 ± 68.08 ng/mL, p 0.001), and were positively correlated with the number of diseased vessels (Spearman's r = 0.611, p 0.001). Increased expression of CTRP5 was detected in human coronary endarterectomy specimens as compared to non-atherosclerotic arteries. Immunofluorescence further showed that CTRP5 was predominantly localized in the endothelium, infiltrated macrophages and smooth muscle cells in the neointima. In vivo and in vitro experiments demonstrated that CTRP5 promoted transcytosis of LDL across endothelial monolayers, as well as the oxidative modification of LDL in endothelial cells. Mechanistically, we found that CTRP5 up-regulated 12/15-lipoxygenase (LOX), a key enzyme in mediating LDL trafficking and oxidation, through STAT6 signaling. Genetic or pharmacological inhibition of 12/15-LOX dramatically attenuated the deposition of oxidized LDL in the subendothelial space and the development of atherosclerosis.These data indicate that CTRP5 is a novel pro-atherogenic cytokine and promotes transcytosis and oxidation of LDL in endothelial cells via up-regulation of 12/15-LOX.

A novel protocol for the activation of the Beckmann rearrangement utilizing the readily available and economical geminal dichloroimidazolidinediones (DCIDs) on a substoichiometric scale (10 mol %) has been developed. A unique self-propagating mechanism for the substoichiometric dichloroimidazolidinedione-activated transformation was proposed and validated. The substrate scope of the developed protocol has been demonstrated by 23 examples with good to excellent yields (mostly 90–98%) in a short time (mostly 10–30 min), including a substrate for synthesizing the monomer of nylon-12 and a complicated steroidal substrate on a preparative scale. This research not only unveils for the first time the synthetic potential of substoichiometric amounts of dichloroimidazolidinediones in promoting chemical transformation but also offers yet another important illustration of the self-propagating cycle in the context of the Beckmann rearrangement activated by a structurally novel organic promoter.

Group B Streptococcus (GBS) was previously not known to be transmitted through food, but an outbreak investigation in Singapore in 2015 documented for the first time an association between GBS Type III Sequence Type 283 infection and consumption of raw fish dishes. As very little is known about the survival of GBS during heat treatment and the stomach transit, its survival under simulated conditions was studied, in comparison with that of Escherichia coli O157:H7 and Listeria monocytogenes. The mean D-values of four GBS strains ranging from 0.72 to 0.88 min in neutral pH tryptone soy broth at 56.4 °C and 0.44–1.43 min at pH 2.35 at 37 °C in simulated gastric fluid, were significantly lower (p

The initial focus on characterizing novel pyrazolo[1,5-a]pyrimidin-7(4H)-one derivatives as DPP-4 inhibitors, led to a potent and selective inhibitor compound b2. This ligand exhibits potent in vitro DPP-4 inhibitory activity (IC50: 80 nM), while maintaining other key cellular parameters such as high selectivity, low cytotoxicity and good cell viability. Subsequent optimization of b2 based on docking analysis and structure-based drug design knowledge resulted in d1. Compound d1 has nearly 2-fold increase of inhibitory activity (IC50: 49 nM) and over 1000-fold selectivity against DPP-8 and DPP-9. Further in vivo IPGTT assays showed that compound b2 effectively reduce glucose excursion by 34% at the dose of 10 mg/kg in diabetic mice. Herein we report the optimization and design of a potent and highly selective series of pyrazolo[1,5-a]pyrimidin-7(4H)-one DPP-4 inhibitors.

A central composite design experiment was conducted and the response surface methodology was performed to optimize the degradation conditions of the mixed bacterial strains that can degrade toluene and H2S. Results showed that the optimum conditions was as follows: pH 6.6, culturing temperature 29.4℃, inoculation quantity 3.0%, additive amount of toluene 3.0μL, additive amount of sodium thiosulfate 4.0g. The selected bacterial strains under the optimized conditions created a good performance of the bio-trickling filter in treating toluene and H2S simultaneously. When the inlet concentration of toluene was 600-900 mg•m-3, the toluene removal efficiency (Re) of the BTF could reach a stable level of 91.2% and the corresponding removal loading was 50.6g•m-3•h-1. Furthermore, the BTF could tolerate an inlet H2S concentration of 74 ppm with a high efficiency of 95% with the toluene Re not affected obviously.

The conventional ion exchange process used for recovery of uridine 5'-monophosphate (UMP) from the enzymatic hydrolysate of RNA is environmentally harmful and cost intensive. In this work, an innovative benign process, which comprises adsorption technology and use of a hyper-cross-linked resin as a stationary phase is proposed. The adsorption properties of this kind of resin in terms of adsorption equilibrium as well as kinetics were evaluated. The influences of the operating conditions, i.e., initial UMP concentration, feed flow rate, and bed height on the breakthrough curves of UMP in the fixed bed system were investigated. Subsequently, a chromatographic column model was established and validated for the prediction of the experimentally attained breakthrough curves of UMP and the main impurity component (phosphate ion) with a real enzymatic hydrolysate of RNA as a feed mixture. At the end of this paper, the crystallization of UMP was carried out. The purity of the final product (uridine 5'-monophosphate disodium, UMPNa2) of over 99.5 % was obtained.

Vascularization remains a large obstacle for creating a functional pancreas-tissue equivalent for transplantation. In this study, a pre-vascularized pancreatic decellularized scaffold was prepared through endothelializing with endothelial progenitor cells (EPCs) in a bioreactor, and the ability to regenerate new blood vessels was detected in vivo. Initially, pancreases of Sprague-Dawley (SD) rats were perfused with 1% Triton X-100 and 0.1% ammonium hydroxide to remove the cellular components while the intact vascular network was preserved. Then, the decellularized scaffold was reseed with EPCs, which were primarily characterized by dual staining for dil-labeled acetylated low-density lipoprotein (Dil-acLDL) and fluorescein isothiocyanate labeled ulex europaeus agglutinin 1 (FITC-UEA-1), to reconstruct the vascular network. Thus, a scaffold covered with EPCs in the vessel structure was created. After that, the scaffold was transplanted into the rat in vivo to observe the anastomosis with the host vascular network. The results showed that EPCs can be located around the blood vessel wall, and re-endothelialized scaffold connected with the host through new blood vessel formation earlier than the control group (p < 0.05). These findings all indicated that the pancreatic decellularized scaffold endothelialized with EPCs may be further applied to solve the problem of blood supply and support the function of insulin-secreting cells after in vivo transplantation.

The suitability of integrating biological and thermal transformation of microalgal biomass to design a biorefinery was studied. The mixed cultivation of Chlorella sp. and Bracteacoccus sp. in city wastewater produced 12 g L−1 of biomass (0.77 g L−1 day−1) and removed nitrates and phosphates by 68% and 75%, respectively. Microalgae outcompeted the contaminating microbes by raising the pH of wastewater to 9.93. The lipid-free residual biomass was pyrolyzed at four heating rates (10, 20, 30, 40 °C min−1) which showed a three-stage pyrolysis. The activation energies (182–256 kJ mol−1) and their corresponding lower enthalpies at the conversional fractions from 0.2 to 0.6 indicated that product formation was being favored. The values of pre-exponential factors (1015-17 s−1), Gibbs free energy (159–190 kJ mol−1) and entropy (43–81 J mol−1) showed efficient pyrolysis. The data may lead to establish a robust microalgal biorefinery to produce biomass and energy along with primary treatment of city wastewater.

ObjectiveChitosan (CS) is currently used as a hemostatic agent in emergencies and in military settings. However, its application is limited owing to its poor hydrophilia at neutral pH. Carboxymethyl chitosan (CMCS) is an important, water-soluble derivative of CS. In this study, we prepared CS and CMCS microspheres (CSMs and CMCSMs, respectively) and evaluated their hemostatic effect.MethodsTo prepare the microspheres of various sizes, we used the emulsion cross-linking technique. CMCSMs were also loaded with etamsylate (DIC). Clotting time in vitro and in a hepatic injury model was examined to evaluate the hemostatic effect.ResultsCMCSMs swelled more and clotted faster than did CSMs. CMCSMs loaded with DIC had no effect on hemostasis.ConclusionsBoth increasing material hydrophilicity and expanding the contact area promoted clotting, whereas chemical cross-linking hampered it because of decreased swelling. CMCSMs are promising candidates for the production of effective hemostatic agents. (Disaster Med Public Health Preparedness. 2017;11:660–667)

In this study, an efficient way by plasma induced mutation was applied to improve the hydroquinone degradation capacity of Serratia marcescens AB 90027 (SM27). The results showed that combined with the selection of hydroquinone tolerance, the mutant with high hydroquinone degradation ability induced by plasma could be achieved. The best dose for plasma mutation was 15 s, which showed a 47.0% higher positive mutation ratio. Besides, the aimed mutant was markedly different from the parent strain (SM27) in colonial traits while cultivated on Kings media. Finally, the hydroquinone degradation ratio reached 70.5% using the induced mutant strain with 1500 mg/L hydroquinone (HQ) after 15 days of cultivation as the selective conditions; however, it was only 46.7% for SM27. The improvement of the degradation capacity by the induced mutant with a high concentration of HQ selection was attributed to its faster growth and higher hydroquinone tolerance compared with that of the parent strain.

Monoclinic-FeOOH with: a = 0.9981 nm, b = 0.2948 nm, n = 1.0485 nm, β = 92.26° was synthesized by the hydrolysis of FeCl3 · 6H2O in micro emulsion including NP-4, octane, water. In this paper, the various morphology and size of the nano particles under different conditions are discussed, and it is found that the optimum conditions for synthesizing acicular β-FeOOH is that R = 6.0, [Fe3+] = 0.02 mol/L within the pH range 1.6–2.0.

Objective: To observe the changes of coagulation and fibrinolysis function in human umbilical cord vein endothelial cells (HUVEC) induced by recombinant human tumor necrosis factor-α (rhTNF-α) and the effect of Naotaifang extract (NTE) on it.Methods: Cultured HUVEC is randomly divided into six groups: Control group, NTE control group (only 2 g/L NTE), rhTNF-α group (100 μg/ L rhTNF-α), and low-dosage, middle-dosage and high-dosage NTE group (100 μg/L rhTNF-α and 0. 67 g/L, 2 g/L, 6 g/L NTE). The coagulation activity of frozen-dissolved HUVEC, von Willebrand factor (vWF) content in the conditioned medium and tissue-type plasminogen activator (tPA) and plasminogen activator inhibitor (PAD activity were to be detected after 24 hrs.Results: Compared with the control group, PAI activity were enhanced, vWF release markedly increased in conditioned medium of TNF-α group (P < 0.01) and the frozen-dissolved HUVEC markedly shortens the rabbit plasma prothrombin time, and the above changes could be significantly inhibited by the 3 dosages of NTE (P < 0.05,P < 0. 01).Conclusion: NTE is effective in inhibiting the coagulation activity of the HUVEC non-stimulated or stimulated by rhTNF-α to enhance the vWF release, and to adjust fibrinolytic function, and mainly to inhibit the PAI activity.

Background and aims In-stent restenosis (ISR) remains a major limitation of percutaneous coronary intervention despite improvements in stent design and pharmacological agents, whereas the mechanism of ISR has not been fully clarified. In the present study, we sought to investigate the potential association of serum soluble TREM-1 (sTREM-1) levels with the incidence of ISR. The role of TREM-1 was evaluated in cultured vascular smooth muscle cells (VSMCs). Methods Out of 1683 patients undergoing coronary intervention and follow-up coronary angiography after approximately one year, 130 patients were diagnosed with ISR, and 150 gender- and age-matched patients with no ISR were randomly included as controls. Levels of sTREM-1 were determined by ELISA. The role of TREM-1 signaling in the activation of VSMCs was tested. Results Serum sTREM-1 concentrations were significantly elevated in patients with than without ISR. Multivariable logistic regression analysis showed that sTREM-1, besides conventional factors, was independently associated with the incidence of ISR. Evident expression of TREM-1 in VSMCs was detected in the neointimal and medial layers of stenotic lesions of mouse carotid ligation models. In cultured VSMCs, expression of TREM-1 was significantly induced upon exposure to lipopolysaccharide. Blocking of TREM-1 with a synthetic inhibitory peptide LP17 dramatically inhibited, whereas TREM-1-activating antibody promoted cellular inflammation, proliferation and migration in VSMCs. Conclusions These data suggest that TREM-1 is a predictive biomarker of ISR and an important mediator of cellular inflammation, migration, and proliferation in VSMCs. Pharmacological inhibition of TREM-1 may serve as a promising approach to attenuate the progression of ISR.

A novel method for selective bromination of graphene was proposed. The reduced graphene oxide (denoted as graphene) used as the raw material, was brominated with 1,3-dibromo-5,5-dimethylhydantoin in the mixture of trifluoromethanesulfonic acid and CH2Cl2 at room temperature. The success of bromination was confirmed by x-ray photoelectron spectroscopy, scanning electron microscopy, energy dispersive x-ray analysis, and Fourier transform-infrared spectroscopy. Moreover, it was found that the bromine concentration of the brominated graphene increased up to 10% Br/C with increasing bromination duration for the first 24 h; then the concentration unexpectedly decreased. The brominated graphene was further functionalized with 4-pyridinyl boronic acid through the Suzuki-coupling reaction. The atomic concentration of Br greatly decreased, whereas the atomic concentration of N increased significantly. This indicated that the functionalization was successful. This proposed bromination method is easy and well-suited for graphene and its derivatives. Additionally, the brominated graphene can be a starting material for constructing other graphene-based functional materials.

Oxidized low-density lipoprotein (oxLDL)-regulated secretion of inflammatory cytokines in smooth muscle cells (SMCs) is regarded as an important step in the progression of atherosclerosis; however, its underlying mechanism remains unclear. This study investigated the role of toll-like receptor 4 (TLR4) in oxLDL-induced expression of inflammatory cytokines in SMCs both in vivo and in vitro. We found that the levels of TLR4, interleukin 1-β (IL1-β), tumor necrosis factor-α (TNFα), monocyte chemoattractant protein 1 (MCP-1) and matrix metalloproteinase-2 (MMP-2) expression were increased in the SMCs of atherosclerotic plaques in patients with femoral artery stenosis. In cultured primary arterial SMCs from wild type mice, oxLDL caused dose- and time-dependent increase in the expression levels of TLR4 and cytokines. These effects were significantly weakened in arterial SMCs derived from TLR4 knockout mice (TLR4−/−). Moreover, the secretion of inflammatory cytokines was blocked by TLR4-specific antibodies in primary SMCs. Ox-LDL induced activation of p38 and NFκB was also inhibited in TLR4−/− primary SMCs or when treated with TLR4-specific antibodies. These results demonstrated that TLR4 is a crucial mediator in oxLDL-induced inflammatory cytokine expression and secretion, and p38 and NFκB activation.

The thermal resistance of different region in the AlGaAs/GaAs HEMTs is measured in a large temperature range by the pulsed switching electrical method. The thermal resistance of the chip solders and base can be measured, respectively, through the cooling response curve processed by the structure method. As the temperature increases, the total thermal resistance increases by 50% from -20°C to 150°C. And the increase of chip thermal resistance is about 67.2% of the total increased thermal resistance. It can be attributed to the decrease of the chip heat conductivity and the enhancement of phonons collisions. The result is significant for the thermal design and the reliability design of HEMTs.

Objective— We aimed to uncover the protein changes of coronary artery in-stent restenosis (ISR) tissue in minipigs with and without streptozotocin-induced diabetes mellitus by quantitative 2-dimensional fluorescence in-gel electrophoresis (2D-DIGE), and to investigate the influences of crucial proteins identified, particularly adipocyte fatty acid binding protein (AFABP), in human arterial smooth muscle cells. Methods and Results— Sirolimus-eluting stents were implanted in the coronary arteries of 15 diabetic and 26 nondiabetic minipigs, and angiography was repeated after 6 months. The intima tissue of significant ISR and non-ISR segments in both diabetic and nondiabetic minipigs was analyzed by 2D-DIGE and MALDI-TOF/TOF mass spectrometry. AFABP level was significantly increased in ISR tissue than in non-ISR tissue in both diabetic and nondiabetic minipigs, with level being higher in diabetic ISR than in nondiabetic ISR tissue. In human arterial smooth muscle cells, overexpression of AFABP significantly altered phenotype and promoted growth and migration, with effects more prominent in high-glucose than in low-glucose medium, whereas AFABP knockdown inhibited these effects. AFABP overexpression increased reactive oxygen species production by upregulating the expression of NADPH oxidase subunits Nox1, Nox4, and P22 through multiple pathways, with elevation of downstream gene cyclin D1, matrix metalloproteinase-2, and monocyte chemoattractant protein-1. However, AFABP-induced effects were inhibited by diphenyleneiodonium, pathway inhibitors, and small interfering RNA. In addition, the supernatant from AFABP-expressing human arterial smooth muscle cells and recombinant AFABP also promoted cellular growth and migration. Conclusion— This study has demonstrated that AFABP is significantly increased in coronary artery ISR segments of both diabetic and nondiabetic minipigs. Increased AFABP expression and secretory AFABP of human arterial smooth muscle cells promote growth and migration via reactive oxygen species-mediated activation.

Waxy maize is prevalently grown in China and other countries due to the excellent characters and economic value. However, its low content of lysine can’t meet the nutritional requirements of humans and livestock. In the present study, we introgressed the opaque2 (o2) allele into waxy maize line Zhao OP-6/O2O2 by using marker-assisted selection (MAS) technique and successfully improved the lysine content and quality of waxy maize. Transcript abundance analysis indicated that the wx1 expression levels had no difference between Zhao OP-6/o2o2 and Zhao OP-6/O2O2. However, Zhao OP-6/o2o2 was characterized by a phenotype of hard and vitreous kernels and accumulation of protein bodies at smaller size (one third of that of parents) but in larger numbers. Biochemical analyses showed that Zhao OP-6/o2o2 had 16.7% less free amino acids than Zhao OP-6/O2O2, especially those derived from glycolytic intermediates, but its content of lysine was increased by 51.6% (0.47% vs. 0.31%). The content of amylopectin was 98.5% in Zhao OP-6/o2o2, significantly higher than that in Zhao OP-6/O2O2 (97.7%). Proteomic analyses indicated that o2 introgression not only decreased the accumulation of various zein proteins except for 27-kDa γ-zein, but also affected other endosperm proteins related to amino acid biosynthesis, starch-protein balance, stress response and signal transduction. This study gives us an intriguing insight into the metabolism changes in endosperm of waxy maize introgressed with opaque2.

In light of the application research of aluminum alloy rheological forming,it introduces the application of Rheoforming with several aluminum alloys based on Rheoforming applied research of Key Lab of Near Net Forming in Jiangxi Province in recent years, there are mainly LAO and LSPSF semi-solid slurry preparation process and rheo-extrusion of LSPSF technology, and Rheo-diecasting of LSPSF technology in industrial applications. The results show that the microstructure of the formed parts are nearly spherical or spherical non-dendritic with equivalent diameter below 70μm and the form factor up to 0.76, the mechanical properties were significantly better than the ordinary extrusion and die casting. Keywords-semi-solid;LAO;LSPSF;rheo-extrusion;Rheo-diecas ting; Aluminum alloy

In view of the difficult separation problem of powder bentonite from solution in water treatment, the development of new type magnetic bentonite composite materials was studied. The adsorption performance of natural bentonite was improved by organic modification. The bentonite was magnetic modified by nano Fe 3 O 4 which was prepared by coprecipitation method. This magnetite composite materials which combined by bentonite and Fe 3 O 4 not only has a better adsorptive capacity for COD and a better separate effect, but also has a simple preparation technology and reaction conditions. This composite materials have been characterized by powder X-ray diffraction (XRD), Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The results revealed that interlamellar spacing of bentonite was increased through organic modification and Fe 3 O 4 particles occured on the surface of bentonite particles and formed magnetic aggregation. These nano-magnetic modified materials with super performances would be used to treat coke wastewater.

100%, 75%, 50%, 25% and 12.5% oxidized dextran T10 (Dex T10) were used as intermediate carriers for conjugating drug daunorubicin (DNR) and antibody anti-human thymocytic globulin (AHTG), to form different immunoconjugates, AHTG:Dex:DNR. It was demonstrated that the conjugate with 25% oxidized Dex T10 as intermediate carrier linked more DNR molecules than the others. The degree of its substitution was 10-11 moles of DNR per mole of AHTG. Moreover, because the amount to reducing agent sodium borohydride (NaBH4), required for the reduction reaction, was relatively small, its damaging effect on AHTG and DNR was lessened accordingly. The antitumor effect of AHTG:Dex:DNR in vitro was tested by using 24-h cytotoxicity assay, with CEM as target cell. Cytotoxic effect of the conjugate was proven and the LD50 was 10.68 micrograms/ml. However, it showed only slight cytotoxic effect on non-target cell K562. When 10 min cytotoxicity assay was performed to show the specific tumor-killing effect of the conjugate, it revealed an obvious cytotoxic activity toward CEM, with the LD50 being 14.79 micrograms/ml, but hardly toward K562. These results suggest that AHTG:Dex:DNR possesses specific cytotoxic effect.

A three-dimensional (3D) graphic model of a single-chain Fv (scFv) which was derived from an anti-human placental acidic isoferritin (PAF) monoclonal antibody (MAb) was constructed by a homologous protein-predicting computer algorithm on Silicon graphic computer station. The structure, surface static electricity and hydrophobicity of scFv were investigated. Computer graphic modelling indicated that all regions of scFv including the linker, variable regions of the heavy (VH) and light (VL) chains were suitable. The VH region and the VL region were involved in composing the “hydrophobic pocket”. The linker was drifted away VH and VL regions. The complementarity determining regions (CDRs) of VH and VL regions surrounded the “hydrophobic pocket”. This study provides a theory basis for improving antibody affinity, investigating antibody structure and analyzing the functions of VH and VL regions in antibody activity.

The effects of chimeric anti-CD4 human/murine chimeric antibody and murine anti-CD4 monoclonal antibody (McAb) on the proliferation induced by anti-CD3 McAb, phytohemagglutinin (PHA), IL-2, and allogeneic cells were studied. The results showed that chimeric anti-CD4 antibody and murine anti-CD4 McAb could inhibit the proliferation induced by the above inducers and the inhibitory effects were related to the dosage of the antibodies.