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The application of phase-change materials (PCMs) for solar energy utilization and thermal energy storage is limited by their low thermal conductivity, undesirable solar-thermal conversion efficienc...

Protein purification is an indispensable step in diverse fields of biological research or production process. Conventional purification methods including the affinity purification or the usage of self-aggregating tags suffered from many drawbacks such as the complicated steps, high cost and low efficiency. Moreover, the fusion tag usually had negative effects on the activity of the target protein. To address the above issues, here we propose a novel protein purification method which needs simple operation steps, and this method is mediated by the combination of CipA protein and a mini-intein (Synechocystis sp. PCC6803 DnaB, Ssp DnaB), depending on the assembly function of CipA and the self-cleavage function of Ssp DnaB. To realize the purification, CipA-DnaB-eGFP protein was expressed and assembled into protein crystalline inclusions (PCIs) in E. coli. Then, only cell lysis, cleavage and centrifugation steps were required to purify eGFP. Purified eGFP was in the supernatant with a purity of over 90%. The cleavage efficiency and the yield of eGFP reached 51.96% and 13.99 ± 0.88 mg/L fermentation broth, respectively. Furthermore, to broaden the application of this approach, three other proteins which were maltose binding protein (MBP), ketoisovalerate decarboxylase (Kivd) and alcohol dehydrogenase (AdhP) were purified with high cleavage efficiency. The purified Kivd and AdhP remained high specific activities. This work demonstrated an effective and convenient protein purification method.

Development of low-cost equipment that can store clean energy, such as solar energy, is effective for alleviating environmental pollution. In this study, the shape-stabilized composite phase change materials (PCMs) based on paraffin wax and carbon foam were prepared. The carbon foam prepared from melamine foam had a good pore structure and was used to encapsulate paraffin wax. The latent heat of melting and cooling of composite PCMs were 221.1 J/g and 213.7 J/g, respectively. Even after 100 cycles, it still showed good thermal performance. Meanwhile, the composite PCMs exhibited good light-to-heat conversion efficiencies of 53.94% and 67.43% at light intensities of 200 mW cm−2 and 300 mW cm−2, respectively. Overall, composite PCMs with excellent thermal performance and cycle stability have application prospects in industries such as construction, solar energy, and battery temperature-control systems.

The fabrication and luminescent performance of novel phosphors Na2YMg2V3O12:Dy3+ were investigated by a conventional solid-state reaction method. Under near-UV light, the Na2YMg2V3O12 host self-activated and released a broad emission band (400–700 nm, with a peak at 524 nm) ascribable to charge transfer in the (VO4)3− groups. Meanwhile, the Na2YMg2V3O12:Dy3+ phosphors emitted bright yellow light within both the broad emission band of the (VO4)3- groups and the sharp peaks of the Dy3+ ions at 490, 582, and 663 nm at a quenching concentration of 0.03 mol. The emission of the as-prepared Na2YMg2V3O12:Dy3+ phosphors remained stable at high temperatures. The obtained phosphors, commercial Y2O3:Eu3+ red phosphors, and BaMgAl10O17:Eu2+ blue phosphors were packed into a white light-emitting diode (WLED) device with a near-UV chip. The designed WLED emitted bright white light with good chromaticity coordinates (0.331, 0.361), satisfactory color rendering index (80.2), and proper correlation to a color temperature (7364 K). These results indicate the potential utility of Na2YMg2V3O12:Dy3+ phosphor as a yellow-emitting phosphor in solid-state illumination.

The limited light absorption, low thermal conductivity, and poor shape stability restrict the widespread application of organic phase change materials (PCMs). Herein, carbon foam (CF) with the light, inter-connective porous, and high-strength was developed based on the phenolic resin to encapsulate organic PCMs, and multi-walled carbon nanotubes (MWCNTs) were added to improve the compressive strength and light absorption at the same time. Then, the polyethylene glycol (PEG) was encapsulated in the CF/MWCNTs composite via a vacuum impregnation method. The modified CF composite could act as an efficient heat transfer channel to improve the thermal conductivity and light-thermal conversion efficiency of PEG. As a result, the PEG/CF composites displayed a high latent enthalpy (156.3 J/g to 170.9 J/g) and an excellent light-thermal conversion efficiency (61%–74%). Furthermore, the PEG/CF10 exhibited the highest thermal conductivity of 0.68 W/(m∙K), which is about 2.24 times higher than that of pure PEG. The as-prepared PEG/CF composites with mechanical strength and thermal stability could exhibit great potential in solar energy utilization, building energy conservation, and waste heat recovery.

A new optical thermometer material—Er3+-doped SrNb2O6—based on the fluorescence intensity ratio was synthesized and investigated by both theoretical calculation and experimental measurement, combining X-ray diffractometry (XRD), XRD Rietveld refinement, scanning electron microscopy, X-ray photon emission spectroscopy, photoluminescence (PL) and PL excitation of qualitative and quantitative analysis, to develop a novel green-emitting phosphor with excellent thermometry sensitivity. The Er3+ ions occupied 4e sites of SrNb2O6, and the stable activator occupation induces luminescence properties of emissions at 525, 531, and 550 nm. The SrNb2O6: Er3+ phosphor possesses an outstanding thermal sensitivity in the measurement region of 298–523 K, where Sa and Sr can achieve 6.15 × 10−3 K−1 and 1093.2711/T2, respectively, at 323 K. The optical thermal properties originated from the thermal excitation and formation of quashing thermal equilibrium between 2H11/2 and 4S3/2 levels, leading to photons on 4S3/2 → 4I15/2 transfer process thermally populate onto 2H11/2 → 4I15/2 transfer process. This work will lay a foundation for further exploration of activator suitability in columbite phosphors, making it practicable to foreseeably improve thermal sensitivity and PL for emergent applications in optical thermometer.

In this paper, a composite phase change material based on paraffin and carbon foam derived from starch was prepared. The paraffin was encapsulated in the carbon foam, which was prepared by using a foaming and steaming method at different carbonization temperatures. Carbon foams comprised amorphous carbon and were impregnated with paraffin to obtain the paraffin/carbon foam composites (PCCs). When carbonized at 1100 °C, the loading percentage of the carbon foam enabled to reach maximum 72.79%. Paraffin encapsulation did not result in any new structure or chemical bonds involved or change in the geometry. The latent heats of the sample were 174.3 J/g at the melting temperature (47.9 °C), and 151.4 J/g at the freezing temperature (52.8 °C). Thermal conductivity of PCCs reached up to 1.93 times than that of paraffin. The composite phase change material fabrication was cost–effective, environment friendly, chemically stable, and suitable for energy–efficient building applications.

This article reviews the recent advances in microfluidic-chip integrated optical biosensors for simultaneous detection of multiple analytes. In particular, the principles and recent progress in different kinds of multiplex optical biosensors and their biological application were reviewed comprehensively. Sensors based on multiplexed detection have absolute advantages in analysis throughput than single assay. The microfluidic chip, a type of micro-total analysis system (µTAS), provides an ideal platform for integration of high-throughput biosensors. Compared with electronic biosensors, benefitted from the technical development in Micro-Electro-Mechanical System, there have been greater advances in the fabrication of optical sensors and microfluidic chip, and then promoting microfluidic-chip integrated optical biosensors for simultaneous detection of multiple analytes.

Background Diabetes is associated with an increased risk of Parkinson's disease (PD). Number of studies have suggested that methylglyoxal (MGO) induced by diabetes is related to PD. However, very little is known about its molecular mechanism. On other hand, 1-acetyl-6, 7- dihydroxyl-1, 2, 3, 4- Tetrahydroisoquinoline(ADTIQ) is a dopamine (DA)-derived tetrahydroisoquinoline (TIQ), a novel endogenous neurotoxins, which was first discovered in frozen Parkinson's disease human brain tissue. While ADTIQ precursor methylglyoxal was also found in diabetic patients related to the glucose metabolism and diabetic patients. Methods LC-MS/MS, 1H NMR and infrared spectroscopy identified the structure of ADTIQ. The Annexin V-FITC/PI, MTT and western blot analysis were used to measure the neurotoxicity of ADTIQ. The levels of ADTIQ and methylglyoxal were detected by LC-MS/MS. Results Here we report the chemical synthesis of ADTIQ, demonstrate its biosynthesis in SH-SY5Y neuroblastoma cell line and investigate its role in the pathogenesis of PD. In addition, a significant increase in the level of ADTIQ was detected in the brains of transgenic mice expressing mutant forms (A53T or A30P) of α-synuclein. ADTIQ also reduced the cell viability and induced mitochondrial apoptosis in dopaminergic cells, suggesting that ADTIQ acts as an endogenous neurotoxin and potentially involved in the pathogenesis of PD. Methylglyoxal, a major byproduct of glucose metabolism and abnormalities in glucose metabolism could influence the levels of ADTIQ. Consistent with the hypothesis, increased levels of ADTIQ and methylglyoxal were detected in the striatum of diabetic rats and SH-SY5Y cells cultured in the presence of high glucose concentrations. Conclusions Increased levels of ADTIQ could be related with Hyperglycemia and death of dopaminergic neurons. General significance The increased levels of ADTIQ could be a reason of dopamine neuron dysfunction in diabetes. Therefore, ADTIQ may play a key role in increasing the risk for PD in patients with diabetes.

Rapid screening of active compounds plays a crucial role in the research and application of complex natural medicines. Herein, a new method of simultaneous label-free multi-drug screening based on a selective aptamer-carboxyfluorescein/graphene oxide energy transfer optical sensor combined with microfluidic chip electrophoretic separation is reported. In this study, seven traditional Chinese medicinal monomers were chosen as targets for the screening of G-quadruplex ligands. The screening results of the G-quadruplex active ligands, including daidzein, berberine hydrochloride, jatrorrhizine hydrochloride, and fangchinoline, and non-active ligands, including geniposide and oxymatrine, were consistent with those reported in literature. Moreover, one new potential G4DNA active drug, jujuboside A, was identified. Molecular simulation of the interaction between G4DNA and drugs was also carried out using HyperChem and AutoDock to verify the results of the experimental screening. It further demonstrated the reliability of our strategy. This novel separation and concentration based multi-sensing strategy provides a simple, rapid, and sensitive tool for simultaneous multi-drug screening, which is very meaningful for drug screening and bio-interaction analysis.

The fabrication and luminescent performance of novel phosphors Na2YMg2V3O12:Dy3+ were investigated by a conventional solid-state reaction method. Under near-UV light, the Na2YMg2V3O12 host self-activated and released a broad emission band (400&ndash, 700 nm, with a peak at 524 nm) ascribable to charge transfer in the (VO4)3&minus, groups. Meanwhile, the Na2YMg2V3O12:Dy3+ phosphors emitted bright yellow light within both the broad emission band of the (VO4)3- groups and the sharp peaks of the Dy3+ ions at 490, 582, and 663 nm at a quenching concentration of 0.03 mol. The emission of the as-prepared Na2YMg2V3O12:Dy3+ phosphors remained stable at high temperatures. The obtained phosphors, commercial Y2O3:Eu3+ red phosphors, and BaMgAl10O17:Eu2+ blue phosphors were packed into a white light-emitting diode (WLED) device with a near-UV chip. The designed WLED emitted bright white light with good chromaticity coordinates (0.331, 0.361), satisfactory color rendering index (80.2), and proper correlation to a color temperature (7364 K). These results indicate the potential utility of Na2YMg2V3O12:Dy3+ phosphor as a yellow-emitting phosphor in solid-state illumination.

More and more studies have suggested that methylglyoxal (MGO) induced by type-2 diabetes is related to Parkinson's disease (PD). However, little is known about the molecular mechanism. In this study, we explored the MGO toxicity in neuroblastoma SH-SY5Y cells. Neurotoxicity of MGO was measured by mitochondrial membrane potential, malondialdehyde, and methylthiazoletetrazolium assays. The levels of dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC), and 1-methyl-4-phenyl-1,2,3,4-tetrahydroisoquinoline (salsolinol) were detected by liquid chromatography-mass spectrometry/mass spectrometry. The expressions of tyrosine hydroxylase (TH) and dopamine transporter (DAT) were detected by reverse transcriptase polymerase chain reaction and western blot analysis. The results showed that MGO induced an increase in TH and DAT expressions in SH-SY5Y neuroblastoma cells, while the levels of dopamine, DOPAC, and endogenous neurotoxin salsolinol also increased. Aminoguanidine (AG) is an inhibitor of MGO. It was found that AG could decrease the reactive oxygen species (ROS) level induced by MGO, but could not inhibit an increase of TH, DAT and dopamine. The increase of dopamine, DOPAC and salsolinol levels could lead to high ROS and mitochondrial damage. This study suggests that ROS caused by dopamine could contribute to the damage of dopaminergic neurons when MGO is increased during the course of diabetes.

Purpose: The radioprotective effects of Dragon's blood ( DB) and its extracts (DBE) were investigated using the chromosomal aberrant test, micronucleus and oxidative stress assay for anti-clastogenic and anti-oxidative activity. Materials and methods: Adult BALB/C mice were exposed to the whole body irradiation with 4 Gy Co-60 gamma rays. DB and DBE were administered orally once a day from 5 days prior to irradiation treatment to 1 day after irradiation. The mice were sacrificed on 24 h after irradiation. The cells of bone marrow were measured by counting different types of chromosomal aberrations and the frequency of micronuclei. Oxidative stress response was carried out by analysis of serum from blood. Results: DB and DBE significantly decreased the number of bone marrow cells with chromosome aberrations after irradiation with respect to irradiated alone group. The administration of DB and DBE also significantly reduced the frequencies of micronucleated polychromatic erythrocytes ( MPCE) and micronucleated normochromatic erythrocytes ( MNCE). In addition, DB and DBE markedly increased the activity of antioxidant enzymes and the level of antioxidant molecular. Malondialdehyde ( MDA) and nitric oxide ( NO) levels in serum were significantly reduced by DB and DBE treatment. Conclusions: Our data suggested that DB and DBE have potential radioprotective properties in mouse bone marrow after Co-60 gamma-ray exposure, which support their candidature as a potential radioprotective agent. (c) 2013 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

The endogenous neurotoxin, 1-acetyl-6,7-dihydroxyl-1,2,3,4 –tetrahydro isoquinoline (ADTIQ), is acatecholamine isoquinoline, indicating its possible involvement in Parkinson's disease. Moreover, it has been assumed to be a bridge between diabetes and Parkinson's disease because metabolic synthesis resembles glucose metabolism. Therefore, the accurate determination of ADTIQ could play an important role in diagnosis of diabetes and Parkinson's disease. Herein, a sensitive and precise method was established to determine ADTIQ by high performance liquid chromatography-electrospray ionization-tandem mass spectrometry in multiple reaction monitoring mode. The [M+H]+ precursor product ions for ADTIQ were 208.1/190.1 and linear range of calibration curve was from 1.0 to 250.0 nM. The limit of detection and limit of quantification of the developed method were 0.2 nM and 1 nM, respectively. The inter-day, intra-day precision, accuracy, and recoveries were acceptable for biological samples. Furthermore, the reported...

α-Synuclein is the major component of Lewy bodies, Lewy neurites, and glial cytoplasmic inclusions. It plays an important role in neurodegenerative diseases such as Parkinson's disease, multiple system atrophy, and other synucleinopathies. However, the pathogenesis and neurodegenerative effects of α-synuclein remain unknown. In this study, we established an α-synuclein and an α-synuclein-EGFP overexpressing U251 cell line. α-Synuclein overexpression increases oxidative stress and alters the cell surface and mitochondrial morphologies. We provide fluorescent-protein tagging, immunofluorescence and ultrastructural evidence showing that α-synuclein accumulations are associated with clusters of cytoplasmic vesicles and the diameter of these vesicles increases by H2O2 in a time- and dose-dependent manner.

Multiple system atrophy (MSA) is a progressive neurodegenerative disease characterized by glial cytoplasmic inclusions containing insoluble α-synuclein. Since Ca(2+) plays an important role in cell degeneration, [Ca(2+)]( i ) in α-synuclein-overexpressed human glioma cells was analyzed by Fura-2 fluorometry. Overexpression of α-synuclein increased the basal level of [Ca(2+)]( i ), and a higher Ca(2+) response to hydrogen peroxide was further observed. The effect that α-synuclein overexpression caused U251 cells to be more vulnerable to hydrogen peroxide was eliminated by Ca(2+) chelator BAPTA-AM or transient receptor potential channels blocker SKF 96365 but not by L-type Ca(2+) channel blocker nimodipine. These findings suggest that the dysregulation of cellular Ca(2+) homeostasis caused by α-synuclein under oxidative stress may contribute to the glial cell death in MSA.

Acetaldehyde, salsolinol (Sal), and 6-hydroxy-1-methyl-1,2,3,4-tetrahydro-β-carboline (6-OH-MTHβC) in neonatal rat brain after acute ethanol treatment were determined by high performance liquid chromatography (HPLC). Free acetaldehyde in rat brain homogenate was derivatized with 2,4-dinitrophenylhydrazine at 60°C for 15 min. The derivatized product was separated on an octadecylsilane-C18 column (150 mm×4.6 mm, 5 μm) and detected with HPLC at 360 nm. The method was proved to be simple, sensitive, and reliable. Compared with control, analysis of neonatal rat brain samples revealed a significant difference in the level of acetaldehyde within 24 h of 5.0 g/kg ethanol treatment (P < 0.05). Also the level of Sal and 6-OH-MTHβC was determined by HPLC performed on a HS F5 column (250 mm×4.6 mm, 5 μm), using Coularray Detector-4 as the electrochemical detector. The results indicated that the levels of Sal and 6-OH-MTHβC in rat brain increased significantly with the elevated level of acetaldehyde after acute alcohol administration. The condensation of acetaldehyde with monoamine neurotransmitters after alcoholism may play an important role in central nervous system dysfunction.

The ability of rapid biomarker quantitation in raw biological samples would expand the application of mass spectrometry in clinical diagnosis. Up until now, the conventional chromatography–mass spectrometry method is time-consuming in both sample preparation and chromatography separation processes, while ambient ionization methods normally suffer from sensitivity. The membrane electrospray ionization (MESI) introduced in this study could not only achieve sensitive biomolecule quantitation, but also minimize the sample handling process. As a unique feature of MESI, both vertical and horizontal chemical separations could be achieved in real-time. With the capability of mass-selectively minimizing matrix effects from salts, small molecules, and macromolecules, ultrasensitive detection of cytochrome C (>500-fold sensitivity improvement) in raw urine samples was demonstrated in less than 20 min.

A phytochemical study was performed on Arundina graminifolia (D.Don) Hochr. by silica gel column and semi-preparative HPLC, and ten stilbenoids were obtained. Their structures were elucidated by NMR and MS spectra and identified as 7-hydroxy-2,4-dimethoxy-9,10-dihydrophenanthrene (1), 4,7-dihydroxy-2-methoxy-9,10-dihydrophenanthrene (2), 2,7-dihydroxy-4-methoxy-9,10-dihydrophenanthrene (3), 3,3'-dihydroxy-5-methoxy-bibenzyl (4), 7-hydroxy-2,8-dimethoxy-phenanthrene-1,4-dione (5), 7-hydroxy-2,10-dimethoxy-phenanthre-ne-1,4-dione (6), 7-dihydroxy-2-methoxy-9,10-dihydrophenanthrene-1,4-dione (7), 7-hydroxy-2-methoxy-phenanthrene-1,4-dione (8), 7-hydroxy-1-(p-hydroxybenzyl)-2,4-dimethoxy-9,10-dihydroxy-phenanthrene (9), 2,7-dihydroxy-1-(p-hydroxybenzyl)-4-methoxy-9,10-dihydroxy-phenanthrene (10). Compounds 5 and 6 were isolated from this plant for the first time. The isolated compounds were examined for their anti-hepatic fibrosis activity against HSC-T6 cells in vitro. The results showed that compounds 4 and 5 exhibited moderate growth inhibitory effects with IC50 61.9 μg/mL and 52.7 μg/mL, respectively.

We previously demonstrated that Cyanobacteria-derived microcystin-LR (MCLR) is able to induce cognitive dysfunction, but the mechanism is not understood. Long-term potential (LTP) in hippocampus is regarded as an important cellular mechanism of learning and memory. Here, the aim of this study was to evaluate the role of MCLR in LTP of hippocampal dentate gyrus (DG) by in vivo electrophysiological recording. We found that MCLR could suppress the induction of LTP in rat hippocampus, whereas simultaneous inhibition of glycogen synthase kinase-3β (GSK-3β) by LiCl or SB216763 attenuated the LTP impairments by MCLR. Furthermore, a decrease of the phosphorylated level at Ser9 of GSK-3β was observed by western blotting after intracerebroventricular (ICV) injection of MCLR, indicating GSK-3β was activated by MCLR. In addition, we showed that ICV administration of MCLR slightly stimulated activity of protein phosphatases (PPs) in the brain, which might activate GSK-3β via dephosphorylation of Ser9 site. Taken together, these findings demonstrated that GSK-3β plays a crucial role in regulating MCLR-induced cognitive deficit.

Pregnant SD rats were exposed to ethanol (25 % (v/v) ethanol at 1.0, 2.0 or 4.0 g/kg body weight from GD8 to GD20) to assess whether ethanol-derived acetaldehyde could interact with endogenous monoamine to generate tetrahydroisoquinoline or tetrahydro-beta-carboline in the fetuses. The fetal brain concentration of acetaldehyde increased remarkably after ethanol administration (2.6 times, 5.3 times and 7.8 times as compared to saline control in 1.0, 2.0 and 4.0 g/kg ethanol-treated groups, respectively) detected by HPLC with 2,4-dinitrophenylhydrazine derivatization. Compared to control, ethanol exposure induced the formation of 1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline (salsolinol, Sal), N-methyl-salsolinol (NMSal) and 1-methyl-6-hydroxy-1,2,3,4-tetrahydro-beta-carboline (6-OH-MTHBC) in fetal rat brains. Determined by HPLC with electrochemical detector, the levels of dopamine and 5-hydroxytryptamine in whole fetal brain were not remarkably altered by ethanol treatment, while the levels of homovanillic acid and 5-hydroxyindole acetic acid in high dose (4.0 g/kg) of ethanol-treated rats were significantly decreased compared to that in the control animals. 4.0 g/kg ethanol administration inhibited the activity of mitochondrial monoamine oxidase (51.3 % as compared to control) and reduced the activity of respiratory chain complex I (61.2 % as compared to control). These results suggested that ethanol-induced alteration of monoamine metabolism and the accumulation of dopamine-derived catechol isoquinolines and 5-hydroxytryptamine-derived tetrahydro-beta-carbolines may play roles in the developmental dysfuction of monoaminergic neuronal systems.