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Allergic bronchopulmonary aspergillosis (ABPA) is an allergic immunological response to Aspergillus fumigatus (Af) exposure, which induces a strong T helper 2 (Th2) response via mechanisms that have yet to be elucidated. The aim of the present study was to investigate the hypothesis that T2 ribonuclease from Af (Af RNASET2) induces M2‑type macrophage polarization to produce a T helper 2 (Th2) immune response. Recombinant Af RNASET2 (rAf RNASET2) was expressed and purified in a prokaryotic pET system and BALB/c mice were immunized with rAf RNASET2 for in vivo analyses. Expression levels of M2 polarization factors were evaluated in RAW264.7 macrophages treated with rAf RNASET2 in vitro using flow cytometry, reverse transcription‑quantitative PCR, and western blot analysis. The results predicted that the mature Af RNASET2 protein (382 amino acids; GenBank no. MN593022) contained two conserved amino acid sequence (CAS) domains, termed CAS‑1 and CAS‑2, which are also characteristic of the RNASET2 family proteins. The protein expression levels of the Th2‑related cytokines interleukin (IL)‑4, IL‑10, and IL‑13 were upregulated in mice immunized with rAf RNASET2. RAW264.7 macrophages treated with rAf RNASET2 showed increased mRNA expression levels of M2 factors [arginase 1, Il‑10, and Il‑13]; however, there was no difference in cells treated with rAf RNASET2 that had been inactivated with a ribonuclease inhibitor (RNasin). The protein expression levels of IL‑10 in macrophage culture supernatant were also increased following stimulation with rAf RNASET2. In addition, rAf RNASET2 upregulated the expression of phosphorylated mitogen activated protein kinases (MAPKs) in RAW264.7 cells, whereas MAPK inhibitors attenuated rAf RNASET2‑induced IL‑10 expression in RAW264.7 cells. In conclusion, the present study reveals that high rAf RNASET2 activity is required for rAf RNASET2‑induced M2 polarization of macrophages and suggests an important immune regulatory role for Af RNASET2 in ABPA pathogenesis.

m6A modification is the most prevalent RNA modification in eukaryotes. As the critical N6‐methyladenosine (m6A) methyltransferase, the roles of methyltransferase like 3 (METTL3) in colorectal cancer (CRC) are controversial. Here, we confirmed that METTL3, a critical m6A methyltransferase, could facilitate CRC progression in vitro and in vivo. Further, we found METTL3 promoted CRC cell proliferation by methylating the m6A site in 3′‐untranslated region (UTR) of CCNE1 mRNA to stabilize it. Moreover, we found butyrate, a classical intestinal microbial metabolite, could down‐regulate the expression of METTL3 and related cyclin E1 to inhibit CRC development. METTL3 promotes CRC proliferation by stabilizing CCNE1 mRNA in an m6A‐dependent manner, representing a promising therapeutic strategy for the treatment of CRC.

Melanoma is a primary reason of death from skin cancer and associated with high lethality. Photothermal therapy (PTT) has been developed into a powerful cancer treatment technique in recent years. Here, we created a low-cost and high-performance PTT agent, Ag@TiO2 NPs, which possesses a high photothermal conversion efficiency of ≈65 % and strong near-infrared (NIR) absorption about 808 nm. Ag NPs were synthesized using a two-step method and coated with TiO2 to obtain Ag@TiO2 NPs by a facile sol-gel method. Because of the oxide, Ag@TiO2 NPs exhibit remarkable high photothermal conversion efficiencies and biocompatibility in vivo and in vitro. Cytotoxicity and therapeutic efficiency of photothermal cytotoxicity of Ag@TiO2 NPs were tested in B16-F10 cells and C57BL/6J mice. Under light irradiation, the elevated temperature causes cell death in Ag NPs-treated (100 μg mL-1 ) cells in vitro (both p

Background Thyroid cancer is the most common endocrine malignancy, papillary thyroid carcinoma (PTC) is the main form of thyroid cancer. The long non-coding RNA (lncRNA) zinc finger antisense 1 (ZFAS1) is highly expressed in various cancer tissues and it has been shown to function as a tumor promoter in various cellular processes. However, the role of ZFAS1 in PTC is not well understood currently. Thus, this study aimed to explore the potential roles of ZFAS1 in the development and progression of PTC. Material and methods PTC tissues (n=80) and noncancerous tissues were collected. Gain- and loss-of-function assays were performed to determine the effect of ZFAS1 on proliferation in K-1 and TPC-1 cells. The ZFAS1/mir-590-3P/HMGA2 aixs were analysed in PTC cell lines. Results We found that the expression of ZFAS1 was increased in PTC tissues and four PTC cell lines (B-CPAP, IHH-4, TPC-1, and K-1). The gain- and loss-of-function assays showed that overexpressing ZFAS1 promoted cell proliferation and inhibited cell apoptosis in PTC cells in vitro. We demonstrated that knockdown of ZFAS1 inhibits tumor growth and upregulation of ZFAS1 promotes tumor growth in vivo. Bioinformatics analysis revealed that miR-590-3p targeted the 3'-UTR of ZFAS1. The double luciferase reporter and RNA-binding protein immunoprecipitation assay demonstrated that miR-590-3p is a target of ZFAS1. Rescue experiments confirmed that miR-590-3p could reverse the effect of ZFAS1 on PTC cells. Moreover, we identified high mobility group AT-hook 2 (HMGA2) to be a downstream target of miR-590-3p and ZFAS1 which activates HMGA2 expression by sponging to miR-590-3p. Conclusion High ZFAS1 expression level was associated with the progression of PTC, and ZFAS1 contributed to PTC progression via miR-590-3p/HMGA2 regulatory aixs. Therefore, ZFAS1 might be a potential therapeutic target for PTC intervention.

Strength is usually compromised with toughness of polymer blends. We report a new way to synchronously strengthen and toughen a typical blend of epoxy resin/nitrile-butadiene rubber (EP/LNBR) with ...

A Janus silica cage was synthesized by selectively grafting an ionic liquid (IL) and poly-N-isopropylacrylamide (PNIPAM) (lower critical solution temperature (LCST)≈32 °C) onto the exterior and interior sides of the mesoporous SiO2 shell. The paramagnetic core inside the cavity is responsible for magnetic collection. The PW12 O40 3- anion is further conjugated onto the IL side by anion exchange. The Janus cage acts as a thermal-responsive reactor for catalytic oxidization of dibenzothiophene (DBT) in the presence of H2 O2 . The sulfide in the model oil can be completely decomposed at 25 °C, whilst the oxidative products are more dissoluble in water and preferentially captured inside the Janus cage. The Janus cage reactor could be regenerated at high temperature above 32 °C after releasing the products.

Ubiquitination, a key and extensive posttranslational modification of proteins, has profound effects on a variety of physiological and pathological processes. The inherent complexity of ubiquitin conjugates makes it highly challenging to study the functional and structural mechanisms of ubiquitination. To address these challenges, accesses to sufficient poly-ubiquitin chains or ubiquitinated proteins are urgently needed. Over the last decade, synthetic protein chemists have developed several novel peptide ligation methods for the preparation of ubiquitin conjugates with precise control over the atomic structure. In this review, we summarize the recent breakthroughs and potential challenges in the chemical synthesis and semi-synthesis of ubiquitin conjugates with respect to the preparation of poly-ubiquitin-based proteins and ubiquitin-based probes.

Investigating on the effect of sodium formate mediated double regulation in TiO2 photocatalytic reduction of cadmium is firstly reported. Multiple characterized methods were used to characterize and confirmed the successful reduction of Cd2+ to the form of metal elements by sodium formate-P25 system. The metal elements were attached to the surface of the composite photocatalyst were directly observed by SEM. The removal efficiency of Cd2+ for the composite photocatalyst was tested. When the addition of sodium formate was 1 g/L, the maximum removal rate of Cd2+ was 94.8% within 10 min. Further experiments showed the mechanism and activity of the combined catalysis of sodium formate and photocatalysis and the role of composite photocatalyst in photocatalytic activity. This is mainly due to the bidentate chelation between sodium formate and TiO2 which makes it possible to adsorb heavy metal ions and the transfer of photo-generated electrons on the bidentate complex, which improves the survival time of the electrons and reduces the metal ions.

Recently, peroxymonosulfate (PMS)-based advanced oxidation processes have exhibited broad application prospects in the environment field. Accordingly, a simple, rapid, and ultrasensitive method is highly desired for the specific recognition and accurate quantification of PMS in various aqueous solutions. In this work, SO4•–-induced aromatic hydroxylation was explored, and based on that, for the first time, a novel fluorescence method was developed for the PMS determination using Co2+ as a PMS activator and benzoic acid (BA) as a chemical probe. Through a suite of spectral, chromatographic, and mass spectrometric analyses, SO4•– was proven to be the dominant radical species, and salicylic acid was identified as the fluorescent molecule. As a result, a whole radical chain reaction mechanism for the generation of salicylic acid in the BA/PMS/Co2+ system was proposed. This fluorescence method possessed a rapid reaction equilibrium (

As one of the most widely existing post-translational modification models, ubiquitination regulates diverse cellular activities. In eukaryotes, K11,48-branched ubiquitin chains play key roles in cell cycle and protein quality control. However, the structural and biochemical properties of K11,48-branched ubiquitin chains have not been well examined. Here we employed the synthetic linkage- and length-defined K11,48-branched ubiquitin chains to examine their binding and hydrolysis properties in vitro. Quantitatively affinity determination of ubiquitin chains to the proteasome ubiquitin receptor S5a indicated that the S5a exhibited preference binding to K11,48-branched chains over K11-linked chains, but not K48-conjugated chains. In addition, deubiquitination experiments were carried out and the results showed that K11,48-branched chains were preferably hydrolyzed by proteasome-associated deubiquitinase Rpn11 than homotypic K11 or K48-linked chains.

Ubiquitin (Ub) chain isopeptide bond mimics are useful molecules for biochemical and biophysical studies. Herein, we report the semi-synthesis of the disulfide-linked K11/K48-branched tri-Ub (Ub311/48(S–S)), the first example of an isopeptide mimic for the branched Ub chains, which have recently emerged as an interesting category of Ub modifications. Our strategy comprised the E1-dependent synthesis of the Ub conjugate of aminoethanethiol, followed by disulfide formation with Ub(K11C, K48C). The structure of the synthetic isopeptide bond mimics was verified by the crystal structure of Ub311/48(S–S). Deubiquitination and pulldown assays indicated that the synthetic Ub311/48(S–S) could be hydrolyzed by linkage-specific deubiquitinases (K11-specific Cezanne and K48-specific OTUB1), and recognized by proteasomal ubiquitin receptor S5a.

Protein chemical synthesis can provide the homogeneous atypical ubiquitin chains that are usually difficult to obtain by other methods. Herein, we report a new one-pot ligation approach for the synthesis of atypical Ub chains based on the Tfacm-protected isoUb building block with operational simplicity and high efficiency. The key intermediate, the Tfacm-protected isoUb building block can be readily prepared by Fmoc SPPS. The practicality and efficiency of the new method is demonstrated by the successful preparation of K11-linked di-Ub.

Inflammation is the initial phase in the healing of cutaneous wounds; however, persistent inflammation will hamper the healing process by generating excess inflammatory cytokines and reactive oxygen species (ROS). Therefore, preventing persistent inflammation and clearing redundant ROS are important strategies in accelerating wound healing. Owing to their unique redox activity, cerium oxide (CeO2) nanoparticles have shown promising potential as antioxidative and anti-inflammatory agents for the treatment of various diseases resulting from oxidative stress. In the present study, we prepared chitosan-coated CeO2 nanocubes (CCNs) and evaluated their cutaneous wound healing potential when topically applied to open excision wounds on adult Sprague Dawley (SD) rats. CCN application significantly increased the wound healing rates and showed superior wound healing capabilities compared to a clinically applied wound healing agent, recombinant human epidermal growth factor (rhEGF). We attribute this superior wound healing ability to their anti-inflammatory ability by decreasing the expression of the inflammatory cytokine tumor necrosis factor-alpha (TNF-α) and increasing the expression of the anti-inflammatory cytokine interleukin-10 (IL-10), as well as to their antioxidative ability by increasing antioxidant enzyme levels. These results suggest that CCNs hold therapeutic potential in treating refractory wounds characterized by persistent inflammation caused by oxidative-stress related diseases such as diabetes.

Chemical ubiquitination is an effective approach for accessing structurally defined, atypical ubiquitin (Ub) chains that are difficult to prepare by other techniques. Herein, we describe a strategy that uses a readily accessible premade isopeptide-linked 76-mer (isoUb), which has an N-terminal Cys and a C-terminal hydrazide, as the key building block to assemble atypical Ub chains in a modular fashion. This method avoids the use of auxiliary-modified Lys and instead employs the canonical and therefore more robust Cys-based native chemical ligation technique. The efficiency and capacity of this isoUb-based strategy is exemplified by the cost-effective synthesis of several linkage- and length-defined atypical Ub chains, including K27-linked tetra-Ub and K11/K48-branched tri-, tetra-, penta-, and hexa-Ubs.

MicroRNAs (miRNAs) function as important regulators of major cellular processes, such as cell cycle, proliferation, development, and apoptosis. Recently, miRNA engineering of Chinese hamster ovary (CHO) cells has emerged as a promising strategy for enhancing therapeutic antibody production. Previously, we have reported that inhibition of deubiquitinase cylindromatosis (CYLD) remarkably enhanced the therapeutic antibody production in CHO cells. However, the mechanisms regulating CYLD in CHO cells remain elusive. Herein, we demonstrated that miR-106b targets CYLD directly, as shown by a series of bioinformatics analyses and experimental assays. Stable overexpression of miR-106b in CHO cells promoted CHO cell viability and subsequent antibody expression in transient transfection assay. Furthermore, the results in fed-batch culture showed that stable overexpression of miR-106b in a CHO-IgG cell line achieved about 0.66-fold promotion in product titer compared to the parental cells. Meanwhile, overexpression of miR-106b did not affect the quality of antibody. Taken together, our findings highlight the effect of miR-106b inhibition in CYLD synthesis and its function in antibody expression as a new target for improving CHO manufacturing cells.

We report the chemical synthesis of the first photo-activatable protein antigen that can be used to study antigen–antibody interaction mediated responses in B cells., We report the chemical synthesis of the first photo-activatable protein antigen that can be used to study antigen–antibody interaction mediated responses in B cells. This strategy facilitated fine tuning of the caged protein antigen to optimize its bioactivity and photochemical properties. One optimal molecule, HEL-K96NPE, was totally inert to hen egg lysozyme (HEL)-specific B cells and could only restore its antigenicity upon photoactivation. Combined with real time live cell imaging, the utility of HEL-K96NPE was demonstrated as a proof of concept to quantify B cell synapse formation and calcium influx responses at the single cell level.

A series of BiOCl x Br y I z solid solutions with controllable band gap and highly enhanced visible light photocatalytic performances were synthesized by a simple hydrolysis method. The samples were characterized by X-ray powder diffraction, UV–vis diffuse reflectance spectra, scanning electron microscope, high-resolution transmission electron microscopy and Brunauer–Emmett–Teller analysis. By adjusting the molar ratio of halogen ions, the band gap of BiOCl x Br y I z could be controllable to the suitable value for a photocatalytic reaction. Especially, BiOCl x Br y I z with a 1:1:2 molar ratio of Cl, Br to I showed the highest visible light photocatalytic activity for the degradation of methyl orange than individual BiOX systems. The degradation efficiency could reach over 90% within 60 min. The possible mechanism of photogenerated carrier transfer and higher photocatalytic activity was analyzed by active species trapping and energy band theory.

Novel dendron encapsulated conjugated organic molecular wire (Den-OPE)–CdSe quantum dot (QD) nanostructures have been designed. By tailoring the size of dendrimers, different amounts of Den-OPEs could be attached to CdSe, which forms different sizes of core–shell Den-OPE–CdSe composites. With an increase in the size of dendrimers, the emission intensity of CdSe QDs increased due to the higher Forster energy transfer (FRET) efficiency from the bigger size Den-OPEs to CdSe QDs.

A novel drug delivery system mediated by ultrasound (US) combined with microbubbles (MBs) (US+MB) could improve local drug concentration to enhance its efficacy. To investigate the influence of US+MB on methylprednisolone (MP), the effect of US+MB combined with MP (US+MB+MP) on lipopolysaccharide (LPS)-induced human mesangial cells (HMCs) and the underlying mechanism were explored in this study. The results revealed that HMCs treated with LPS underwent significant proliferation and exhibited an increase in nuclear transcription factor-κB (NF-κB) and transforming growth factor-β1 (TGF-β1) expression and a decrease in cellular apoptosis. This effect was significantly inhibited by MP (30-100 μg/ml), US combined with MBs (3.22 × 107 and 8.05 × 107 bubbles/ml), and US combined with both MBs (1.29 × 107 bubbles/ml) and MP (12 μg/ml) (US+MB1+MP12). The effect of US+MB1+MP12 was better than the effect of 12 μg/ml of MP alone and was similar to the effect of 100 μg/ml of MP. Additionally, the intracellular free MP content was significantly higher in the US+MB1+MP12 group than in the MP12 group. US combined with MBs not only inhibited LPS-induced HMC proliferation and NF-κB and TGF-β1 expression and increased cellular apoptosis but also synergized with the pharmacologic effect of MP. The mechanism is partially due to the US-assisted MB local drug delivery and the anti-inflammatory effect induced by US combined with MBs.

Background Although alpha-fetoprotein (AFP) is a useful serologic marker of hepatocellular carcinoma (HCC), it is not sufficiently sensitive to differentiate HCC and liver cirrhosis (LC) caused by hepatitis B virus (HBV) infection. Aims The aim is to discover novel noninvasive specific serum biomarkers for the differential diagnosis of HBV-related HCC and LC. Methods With a highly optimized peptide extraction and matrix-assisted laser desorption/ionization time of flight/time of flight mass spectrometric approach, we investigated serum peptide profiles of 80 HCC and 67 LC patients. Three supervised machine learning methods were employed to construct classifiers. Receiver operator curves were plotted to evaluate the performance of classifiers. Results With a support vector machine-based strategy, we picked nine peaks with m/z ratios of 819.49, 1076.14, 1341.72, 2551.44, 3156.44, 3812.88, 4184.26, 4465.92, and 4776.41 to construct the classifier. We proposed a novel method for distinguishing HCC from cirrhosis, based on a multilayer perceptron (MLP) method. We obtained a sensitivity of 90.0%, specificity of 79.4%, and overall accuracy of 85.1% on an independent test set. The combination of the MLP model and serum AFP level outperformed serum AFP marker alone in distinguishing HCC patients from LC patients. In this experience, sensitivity increased from 62.5% to 87.5%, and specificity increased from 79.4% to 88.2%. Conclusions Our results indicate that the MLP model is a novel and useful serum peptide pattern for distinguishing HCC and LC. The peptidome signature alone or together with serum AFP determination may be a more effective method for early diagnosis of HCC in patients with HBV-related LC.

Several reaction pathways on the potential energy surface (PES) for the radical-radical reaction of CH3O2 + CN have been investigated theoretically at the CCSD (T)//B3LYP/6-311++G (3df, 3pd) level. The calculations show that the CH3OOCN and CH3OONC are the most stable intermediates. The direct dissociation of CH3OOCN (im2) leading to CH3O + NCO is predominant on the energy surface, and the CH2O + HNCO are expected to be secondary products.

Heavy oil wastewater must be pretreated if membrane technology was used to treat it. According to the quality analysis of heavy oil wastewater, the processes of silica removal by magnesia agent, filtration by fiber ball and adsorption by activated carbon were employed to treat heavy oil wastewater so that treated water could meet the demand of feed for membrane.

The singlet potential surface of the OH + HN2 reaction has been investigated at the B3LYP/6-311++G (3df, 3pd) level. The single-point energy calculations are performed at the high-level CCSD (T) / 6-311++G (3df, 3pd) for more accurate energy values. DFT calculations show that the most favorable association way starts with a barrierless addition of the OH to HN2 leading to HNN-OH (im6). The adduct im6 goes through an H shift from N atom to O atom, forming the product of H2O and N2.

One of the neuropathological hallmarks of Alzheimer's disease (AD) is the occurrence of neurofibrillary tangles (NFTs) that are composed of abnormally hyperphosphorylated microtubule-associated protein tau. Abnormal tau hyperphosphorylation is mainly induced due to the imbalance between protein kinases and phosphatases. In the tanglerich subregions of the hippocampus and parietal cortex in the brain of AD patients, the levels of the phosphorylationdependent protein peptidyl-prolyl cis-trans isomerase (Pin1) were found to be low. Although Pin1 can regulate tau phosphorylation, it is not clear whether the inhibition of glycogen synthase kinase 3 (GSK-3), the primary mediator of tau phosphorylation in AD, could reverse tau hyperphosphorylation induced due to the down-regulation of Pin1. We found that while suppression of Pin1, either by using its inhibitor Juglone or a shRNA plasmid against Pin1, induces tau hyperphosphorylation and GSK-3β activation both in vivo and in vitro, inhibition of GSK-3β by SB216763 or LiCl reverses tau hyperphosphorylation. Our data suggest that GSK-3β activation plays an important role in tau hyperphosphorylation induced by the down-regulation of Pin1, and the inhibition of GSK-3β might be a potential therapeutic approach for AD pathology.

The triplet potential surface of the O (3P) + HCONH2 reaction has been investigated at the CCSD (T)//B3LYP/6-311G (d,p) level. DFT calculations show that the reaction occurs dominantly via the H - abstraction rather than the O- addition mechanism on the triplet potential surface. The product of OH and CONH2 should be the major product, which obtained by a direct dissociation of the adduct im6 without an exit barrier.

This study compared the effects of a carbohydrate-electrolyte-protein solution (CEPS, 2% protein plus 4% carbohydrate), carbohydrate-electrolyte solution (CES, 6% carbohydrate), and noncaloric sweetened placebo (PLA) on both 21-km running performance and cognitive function. Eleven female recreational endurance runners performed a 21-km time-trial running on three occasions, separated by at least 28 days. In a randomized cross-over design, they ingested CEPS, CES, or PLA at a rate of 150 mL every 2.5 km with no time feedback. A cognitive function test was performed before and after the run. Participants ingested approximately 24 g/h carbohydrate plus 12 g/h protein in CEPS trial, and 36 g/h carbohydrate in CES trial during each 21-km trial. Time to complete the time-trial was slightly shorter (P < 0.05) during CES (129.6 ± 8.8 min) than PLA (134.6 ± 11.5 min), with no differences between CEPS and the other two trials. The CEPS trial showed higher composite of visual motor speed than the PLA trial (P < 0.05). In conclusion, CES feedings might improve 21-km time-trial performance in female recreational runners compared with a PLA. However, adding protein to the CES provided no additional time-trial performance benefit. CEPS feeding during prolonged exercise could benefit visual motor speed compared to PLA alone, but no differences in the performance of the other cognitive function tests were found.

Longer amyloid-beta (Aβ) peptides (43 to 49 amino acids) play essential roles in the pathology of Alzheimer's disease (AD). The difficulty in the preparation of longer Aβ peptides is still an obstacle to elucidate their roles in AD. Herein we report a robust and efficient strategy for the chemical synthesis of longer Aβ peptides (Aβ48 and Aβ49). A key feature of this method is the installation of removable Arg4-tagged backbone modification groups into the hydrophobic region of Aβ. This modification can improve the handling properties of the purification, ligation and mass characterization of longer Aβ peptides. The practicability of the new method has been demonstrated by the successful synthesis of Aβ48 and Aβ49 peptides.

Uniform bismuth ferrite BiFeO3 nanoparticles (below 60 nm) were successfully synthesized via a simple hydrothermal route with the assistance of KOH as mineralizer and EDTA as the chelating agent. The effects of mineralizer and chelating agent on the phase formation, and morphology of these particles were investigated. Size dependent magnetic properties of as-prepared particles at room temperature were investigated.

Ethyl acetate was synthesized by catalytic distillation using packing solid super acid catalyst of SO42-/Al2O3made by oneself. The effects of process parameters such as the ratio between acetic acid and ethanol, the feed flow rate of ethanol and reflux ratio on catalytic distillation were observed. The best operation parameters were determined. It was beneficial for synthesis of ethyl acetate when n(acetic acid)/n(ethanol) was 1/3, the feed flow rate of ethanol was 3mol/l and reflux ratio was 2.

Aptamer is a kind of synthetic oligonucleotides discriminated by in vitro screening and systematic evolution of exponential enrichment technology (SELEX), which can bind to certain targets (small molecules, proteins, or even entire cells) with extremely high specificity. Owing to the advantages of simple preparation, easy modification and good stability, aptamers have been used to construct biosensors for the detection of pathogenic microorganisms. This paper presents the latest advances in SELEX for screening aptamers for pathogenic microorganisms, demonstrates some reported aptamers for pathogenic microorganisms (protozoa, viruses, bacteria), and reviews aptamer based biosensors for detection of pathogenic microorganisms. Finally, the new trends in aptamer based biosensors for detection of pathogenic microorganisms are also discussed.

J. Neurochem. (2012) 120, 157–164. Abstract Neuroglobin (Ngb) is a recently identified member of hemoglobin family, distributed mainly in central and peripheral nervous systems. Recent studies suggest that Ngb can protect neural cells from β-amyloid-induced toxicity in Alzheimer disease (AD). Hyperphosphorylation of tau is another characterized pathological hallmark in the AD brains; however, it is not reported whether Ngb also affects tau phosphorylation. In this study, we found that the level of Ngb was significantly reduced in Tg2576 mice (a recognized mouse model of AD) and TgMAPt mice, and the level of Ngb was negatively correlated with tau phosphorylation. Over-expression of Ngb attenuates tau hyperphosphorylation at multiple AD-related sites induced by up-regulation of glycogen synthase kinase-3β (GSK-3β), a crucial tau kinase. While Ngb activates Akt and thus inhibits GSK-3β, simultaneously inhibition of Akt abolishes the effects of Ngb on GSK-3β inhibition and tau hyperphosphorylation. Our data indicate that Ngb may attenuate tau hyperphosphorylation through activating Akt signaling pathway, implying a therapeutic target for AD.

A control strategy for tuning the film morphology of asymmetric polystyrene-b-poly(4-vinylpyridine) (PS-b-P4VP) block copolymers (BCPs) is reported. After preparation of the film by spin-coating method, the as-cast films were annealed in different solvent vapor. It is found that chloroform is a wonderful solvent for forming PS-b-P4VP regular pattern. Otherwise, with changing the concentration of PS-b-P4VP, cylindrical or parallel nanostructures could be attained. The PS-b-P4VP films with cylindrical structure are used as template to deposit FePt nanoparticles into the pores. Nanoparticles reaching the bottom of the holes form a disordered magnetic array.

A new type of nanohybrids containing carbon nanotubes (CNTs) and CdSe quantum dots (QDs) was prepared using an electrostatic self-assembly method. The CdSe QDs were capped by various mercaptocarboxylic acids, including thioglycolic acid (TGA), dihydrolipoic acid (DHLA) and mercaptoundecanoic acid (MUA), which provide shell thicknesses of ~5.2, 10.6 and 15.2 Å, respectively. The surface-modified CdSe QDs are then self-assembled onto aridine orange-modified CNTs via electrostatic interaction to give CdSe/CNT nanohybrids. The photoluminescence (PL) efficiencies of the obtained nanohybrids increase significantly with the increase of the shell thickness, which is attributed to a distance-dependent photo-induced charge-transfer mechanism. This work demonstrates a simple mean for fine tuning the PL properties of the CdSe/CNT nanohybrids and gains new insights to the photo-induced charge transfer in such nanostructures.

The effects of anodic voltages on the morphology, wettability and photocurrent response of the porous titanium dioxide films prepared by electrochemical oxidation in a hydrofluoric acid (HF)/chromic acid electrolyte have been studied. The porous titanium dioxide films showed an increased surface roughness with the increasing anodizing voltages. By controlling the films morphology and surface chemical composition, the wettability of the porous titanium dioxide films could be easily adjusted between superhydrophilicity and superhydrophobicity. X-ray diffraction (XRD), Raman and UV–vis spectroscopy revealed that the obtained titanium dioxide films were in anatase phase. The titanium dioxide films showed clear photocurrent response, which decreased dramatically with the increase of the anodizing voltages. This study demonstrates a straightforward strategy for preparing porous titanium dioxide films with tunable properties, and especially emphasizes the importance of understanding their morphology/properties relationship.

Highly ordered arrays consisting uniform fluorescent cadmium selenide ( CdSe ) quantum dots (QDs) ring or dot structures were obtained by self-assembly of QDs on chemically patterned substrates. In this method, Au substrates with alternating hydrophobic and hydrophilic square patterns are firstly fabricated by microcontact printing, which allows water droplets to condense on the hydrophilic regions to provide two-dimensional template arrays. The CdSe QDs are then assembled at the liquid/liquid interfaces to give uniform micro or nanostructures. The shape and size of the rings and dots can be tailored by controlling the relative evaporation speed of the water and the organic solvents. The obtained nanostructures have ideal topography to avoid substrate-induced fluorescence quenching.

Uniform TiO2 nanotube arrays were fabricated on titanium substrates by self-organized anodic oxidation. CdSe quantum dots (QDs) were assembled onto TiO2 nanotube layers, which serve as sensitizers. The photocurrent measurement shows that annealing is essential to increase the anatase phase and hence increase the photocurrent. Attachment of CdSe QDs dramatically increased the photocurrent of TiO2 nanotubes in the visible region. The photo-response of CdSe sensitized TiO2 also shows strong dependence to the QDs size. The possible mechanism for energy transfer between the CdSe QDs and the TiO2 nanotubes has been discussed.

Single phase BiOClxBryIz solid solutions with controllable band gap and highly enhanced visible light photocatalytic performance are prepared by hydrolysis of stoichiometric amounts of aqueous NaCl, NaBr, KI, and NaOAc solutions to which a Bi(NO3)3 solution in glacial AcOH is given.

The degradation of polycarbonate was studied by measuring the absorbance of bisphenol A, which is the main degradation products of polycarbonate. The important factors have been researched, such as temperature, the pH and reaction time. The result shows that the pH and temperature have an effect on the degradation of polycarbonate.

Successive peptide ligation using a one-pot method can improve the efficiency of protein chemical synthesis. Although one-pot three-segment ligation has enjoyed widespread application, a robust method for one-pot four-segment ligation had to date remained undeveloped. Herein we report a new one-pot multisegment peptide ligation method that can be used to condense up to four segments with operational simplicity and high efficiency. Its practicality is demonstrated by the one-pot four-segment synthesis of a plant protein, crambin, and a human chemokine, hCCL21.

Intracellular accumulation of the abnormally modified tau is hallmark pathology of Alzheimer’s disease (AD), but the mechanism leading to tau aggregation is not fully characterized. Here, we studied the effects of tau SUMOylation on its phosphorylation, ubiquitination, and degradation. We show that tau SUMOylation induces tau hyperphosphorylation at multiple AD-associated sites, whereas site-specific mutagenesis of tau at K340R (the SUMOylation site) or simultaneous inhibition of tau SUMOylation by ginkgolic acid abolishes the effect of small ubiquitin-like modifier protein 1 (SUMO-1). Conversely, tau hyperphosphorylation promotes its SUMOylation; the latter in turn inhibits tau degradation with reduction of solubility and ubiquitination of tau proteins. Furthermore, the enhanced SUMO-immunoreactivity, costained with the hyperphosphorylated tau, is detected in cerebral cortex of the AD brains, and β-amyloid exposure of rat primary hippocampal neurons induces a dose-dependent SUMOylation of the hyperphosphorylated tau. Our findings suggest that tau SUMOylation reciprocally stimulates its phosphorylation and inhibits the ubiquitination-mediated tau degradation, which provides a new insight into the AD-like tau accumulation.

A microporous chiral complex KMn2[(L-C4H2O6)2B] · 3H2O was synthesized solvothermally in the presence of l -tartaric acid. In this framework, Mn2+ ions exhibit distorted octahedral coordination and the tartrate group is bonded to the B atom as a bidentate ligand via oxygen atoms of neighbouring hydroxyl groups.

Objective: To investigate the differential salivary protein expression profiles between children with severe early childhood caries (S-ECC) and caries-free (CF) children at the age of 3 years. Methods: We used matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) combined with weak cation exchange magnetic beads, and peptide mass fingerprints were created by scanning mass spectrometry signals. Salivary samples from 20 children were analyzed (10 for each group). Results: Eleven protein peaks were significantly different (p < 0.05) between the two groups. Eight of these peaks were higher in the S-ECC group and three were higher in the CF group. To establish a diagnostic model for discrimination between the two groups, we chose three peptides (3,186.2, 3,195.8 and 3,324.8 Da) that exhibited the best fitted curve, by which the two groups were better separated when compared with other combinations. Conclusions: The salivary biomarkers identified revealed significant differences between the CF and the S-ECC group. Our results provide novel insight into the salivary protein profile of preschool-age children with dental caries and may lead to the development of a new strategy for screening high-risk populations.