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Background The most common etiologies of Cushing's syndrome (CS) are adrenocorticotropic hormone (ACTH)-producing pituitary adenoma (pitCS) and primary adrenal gland disease (adrCS), both of which burden patients with metabolic disturbance. The aim of this study was to compare the metabolic features of pitCS and adrCS patients. Methods A retrospective review including 114 patients (64 adrCS and 50 pitCS) diagnosed with CS in 2009–2019 was performed. Metabolic factors were then compared between pitCS and adrCS groups. Results Regarding sex, females suffered both adrCs (92.2%) and pitCS (88.0%) more frequently than males. Regarding age, patients with pitCS were diagnosed at a younger age (35.40 ± 11.94 vs. 39.65 ± 11.37 years, P = 0.056) than those with adrCS, although the difference was not statistically significant. Moreover, pitCS patients had much higher ACTH levels and more serious occurrences of hypercortisolemia at all time points (8 AM, 4 PM, 12 AM) than that in adrCS patients. Conversely, indexes, including body weight, BMI, blood pressure, serum total cholesterol, LDL-C, HDL-C, triglycerides, fasting plasma glucose, and uric acid, showed no differences between adrCS and pitCS patients. Furthermore, diabetes prevalence was higher in pitCS patients than in adrCS patients; however, there were no significant differences in hypertension or dyslipidemia prevalence between the two. Conclusions Although adrCS and pitCS had different pathogenetic mechanisms, different severities of hypercortisolemia, and different diabetes prevalences, both etiologies had similar metabolic characteristics.

Phosphofructokinase B (PfkB) belongs to the ribokinase family, which uses the phosphorylated sugar as substrate, and catalyzes fructose-6-phosphate into fructose-1,6-diphosphate. However, the structural basis of Mycobacterium marinum PfkB is not clear. Here, we found that the PfkB protein was monomeric in solution, which was different from most enzymes in this family. The crystal structure of PfkB protein from M. marinum was solved at a resolution of 2.21 A. The PfkB structure consists of two domains, a major three-layered α/β/α sandwich-like domain characteristic of the ribokinase-like superfamily, and a second domain composed of four-stranded β sheets. Structural comparison analysis suggested that residues G236, A237, G238, and D239 could be critical for ATP catalysis and substrate binding of PfkB. Our current work provides new insights into understanding the mechanism of the glycolysis in M. marinum.

The detection of perfluoroalkyl substances (PFASs) in surface waters is concerning because these compounds are bioaccumulative and potentially biotoxic. Therefore, the development of simple, efficient, and energy-saving methods to remove these persistent organic pollutants from water is extremely urgent. Due to the stability and typically low concentrations of PFASs conventional removal processes and some advanced treatment processes (such as coagulation and electrocatalysis) are not suitable for PFAS removal due to their relatively poor removal efficiency or harsh reaction conditions. Membrane processes, such as nanofiltration (NF) and reverse osmosis (RO), can effectively remove multiple substances, are energy-saving, and do not require a phase change. Therefore, these PFAS removal methods show more promise for practical application. This article reviews the current research progress regarding the influence of typical NF and RO factors on PFAS removal. In addition, the research status and prospects of other water treatment processes combined with membrane processes are summarized and assessed.

The oxidative desulfurization (ODS) of organic sulfur compounds over tungsten oxide supported on highly ordered mesoporous SnO2 (WOx/meso-SnO2) was investigated. A series of WOx/meso-SnO2 with WOx contents from 10 wt% to 30 wt%, were prepared by conventional wet impregnation. The physico-chemical properties of the WOx/meso-SnO2 catalysts were characterized by X-ray diffraction (XRD), N2 adsorption–desorption isotherms, electron microscopy, Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, and the temperature-programmed reduction of hydrogen (H2-TPR). The characterization results indicated that these catalysts possessed mesoporous structures with uniform pores, high specific surface areas, and well-dispersed polyoxotungstate species on the surface of meso-SnO2 support. The ODS performances were evaluated in a biphasic system (model oil/acetonitrile, Sinitial = 2000 ppm), using H2O2 as an oxidant, and acetonitrile as an extractant. Dibenzothiophene (DBT) in the model oil was removed completely within 60 min at 50 °C using 20 wt% WOx/meso-SnO2 catalyst. Additionally, the effect of reaction temperature, H2O2/DBT molar ratio, amount of catalyst and different sulfur-containing substrates on the catalytic performances were also investigated in detail. More importantly, the 20 wt% WOx/meso-SnO2 catalyst exhibited 100% surfur-removal efficiency without any regeneration process, even after six times recycling.

Scaffold-based peptides (SBPs) are fragments of large proteins that are characterized by potent bioactivity, high thermostability, and low immunogenicity. Some SBPs have been approved by the FDA for human use. In the present study, we developed SBPs from the venom gland of Deinagkistrodon acutus (D. acutus) by combining transcriptome sequencing and Pfam annotation. To that end, 10 Kunitz peptides were discovered from the venom gland of D. acutus, and most of which peptides exhibited Factor XIa (FXIa) inhibitory activity. One of those, DAKS1, exhibiting strongest inhibitory activity against FXIa, was further evaluated for its anticoagulant and antithrombotic activity. DAKS1 prolonged twofold APTT at a concentration of 15 μM in vitro. DAKS1 potently inhibited thrombosis in a ferric chloride-induced carotid-artery injury model in mice at a dose of 1.3 mg/kg. Furthermore, DAKS1 prevented stroke in a transient middle cerebral-artery occlusion (tMCAO) model in mice at a dose of 2.6 mg/kg. Additionally, DAKS1 did not show significant bleeding risk at a dose of 6.5 mg/kg. Together, our results indicated that DAKS1 is a promising candidate for drug development for the treatment of thrombosis and stroke disorders.

DNA modifications, represented by 5‐methylcytosine (5mC), 5‐hydroxymethylcytosine (5hmC), 5‐formylcytosine (5fC), and 5‐carboxylcytosine (5caC), play important roles in epigenetic regulation of biological processes. The specific recognition of DNA modifications by the transcriptional protein machinery is thought to be a potential mechanism for epigenetic‐driven gene regulation, and many modified DNA‐specific binding proteins have been uncovered. However, the panoramic view of the roles of DNA modification readers at the proteome level remains largely unclear. Here, a recently developed concatenated tandem array of consensus transcription factor (TF) response elements (catTFREs) approach is employed to profile the binding activity of TFs at DNA modifications. Modified DNA‐binding activity is quantified for 1039 TFs, representing 70% of the TFs in the human genome. Additionally, the modified DNA‐binding activity of 600 TFs is monitored during the mouse brain development from the embryo to the adult stages. Readers of these DNA modifications are predicted, and the hierarchical networks between the transcriptional protein machinery and modified DNA are described. It is further demonstrated that ZNF24 and ZSCAN21 are potential readers of 5fC‐modified DNA. This study provides a landscape of TF–DNA modification interactions that can be used to elucidate the epigenetic‐related transcriptional regulation mechanisms under physiological conditions., Modified‐transcription factor response elements (TFREs) are developed, which profile the binding activity of TFs at DNA modifications (5mC, 5hmC, and 5fC), covering 70% of the TFs in the genome. A landscape of TF–DNA modification interaction is provided and the epigenetic‐related transcriptional regulation mechanisms are elucidated under physiological conditions. Potential readers of 5fC‐modified DNA are demonstrated and validated.

To identify the key residues of Thermus thermophilus (T. thermophilus) RTCB in RNA ligation and DNA activation. The biochemical activities of RTCB from T. thermophilus were purified, characterized, and compared. Structure and sequence alignment between T. thermophilus RTCB and Pyrococcus horikoshii (P. horikoshii) RTCB identified six conserved residues (D64, D95, N203, H204, E207, H399) that were essential for RNA ligation. Mutation analysis showed that the expression levels of mutants D95A, N203A, H204A, E207A and H399A were relatively low. Compared to wide-type RTCB, variant D64A protein had no RNA ligation and DNA activation activity. In addition, T. thermophilus RTCB showed acceptable catalytic activity of 3′-phosphate DNA activation at 37 °C. D64 was proved to be essential for RTCB-catalyzed RNA ligation and DNA activation (from 37 to 70 °C) in T. thermophilus.

Background: High plasma levels of trimethylamine N-oxide (TMAO) and its precursor choline have been linked to stroke; however, their association with cerebral small vessel disease remains unclear. Here we evaluated the association of plasma levels of TMAO and choline with imaging markers of cerebral small vessel disease, including white matter hyperintensities, lacunes, and cerebral microbleeds.Methods: We performed a baseline cross-sectional analysis of a multicenter hospital-based cohort study from 2015 to 2018. The data were collected from 30 hospitals in China and included 1,098 patients with ischemic stroke/transient ischemic attack aged ≥18 years. White matter hyperintensities, lacunes, and cerebral microbleeds were evaluated with the patients' demographic, clinical, and laboratory information removed. White matter hyperintensities were rated using the Fazekas visual grading scale, while the degree of severity of the lacunes and cerebral microbleeds was defined by the number of lesions.Results: Increased TMAO levels were associated with severe white matter hyperintensities [adjusted odds ratio (aOR) for the highest vs. lowest quartile, 1.5; 95% confidence interval (CI), 1.0–2.1, p = 0.04]. High TMAO levels were more strongly associated with severe periventricular white matter hyperintensities (aOR for the highest vs. lowest quartile, 1.6; 95% CI, 1.1–2.3, p = 0.009) than deep white matter hyperintensities (aOR for the highest vs. lowest quartile, 1.3; 95% CI, 0.9–1.9, p = 0.16). No significant association was observed between TMAO and lacunes or cerebral microbleeds. Choline showed trends similar to that of TMAO in the association with cerebral small vessel disease.Conclusions: In patients with ischemic stroke or transient ischemic attack, TMAO and choline appear to be associated with white matter hyperintensities, but not with lacunes or cerebral microbleeds; TMAO and choline were associated with increased risk of a greater periventricular, rather than deep, white matter hyperintensities burden.

Background Esterases and lipases hydrolyze short-chain esters and long-chain triglycerides, respectively, and therefore play essential roles in the synthesis and decomposition of ester bonds in the pharmaceutical and food industries. Many SGNH family esterases share high similarity in sequences. However, they have distinct enzymatic activities toward the same substrates. Due to a lack of structural information, the detailed catalytic mechanisms of these esterases remain barely investigated. Results In this study, we identified two SGNH family esterases, CrmE10 and AlinE4, from marine bacteria with significantly different preferences for pH, temperature, metal ion, and organic solvent tolerance despite high sequence similarity. The crystal structures of these two esterases, including wild type and mutants, were determined to high resolutions ranging from 1.18 Å to 2.24 Å. Both CrmE10 and AlinE4 were composed of five β-strands and nine α-helices, which formed one compact N-terminal α/β globular domain and one extended C-terminal domain. The aspartic residues (D178 in CrmE10/D162 in AlinE4) destabilized the conformations of the catalytic triad (Ser-Asp-His) in both esterases, and the metal ion Cd2+ might reduce enzymatic activity by blocking proton transfer or substrate binding. CrmE10 and AlinE4 showed distinctly different electrostatic surface potentials, despite the similar atomic architectures and a similar swap catalytic mechanism. When five negatively charged residues (Asp or Glu) were mutated to residue Lys, CrmE10 obtained elevated alkaline adaptability and significantly increased the enzymatic activity from 0 to 20% at pH 10.5. Also, CrmE10 mutants exhibited dramatic change for enzymatic properties when compared with the wide-type enzyme. Conclusions These findings offer a perspective for understanding the catalytic mechanism of different esterases and might facilitate the industrial biocatalytic applications.

Glucosidases play key roles in many diseases and are limiting enzymes during cellulose degradation, which is an important part of global carbon cycle. Here, we identified a novel β-glucosidase, CmGH1, isolated from marine bacterium Croceicoccus marinus E4A9T. In spite of its high sequence and structural similarity with β-xylosidase family members, CmGH1 had enzymatic activity toward p-nitrophenyl-β-D-glucopyranoside (p-NPG) and cellobiose. The K m and K cat values of CmGH1 toward p-NPG were 0.332 ± 0.038 mM and 2.15 ± 0.081 min-1, respectively. CmGH1 was tolerant to high concentration salts, detergents, as well as many kinds of organic solvents. The crystal structure of CmGH1 was resolved with a 1.8 A resolution, which showed that CmGH1 was composed of a canonical (α/β)8-barrel catalytic domain and an auxiliary β-sandwich domain. Although no canonical catalytic triad residues were found in CmGH1, structural comparison and mutagenesis analysis suggested that residues Gln157 and Tyr264 of CmGH1 were the active sites. Mutant Q157E significantly increased its hydrolase activity up to 15-fold, whereas Y264E totally abolished its enzymatic activity. These results might provide new insights into understanding the different catalytic mechanism during evolution for β-glucosidases and β-xylosidases.

A self-assembled Cu-Fe-Ni-Cr-Si immiscible composite with a bilayer structure was produced by laser induction hybrid cladding (LIHC) as a result of liquid phase separation (LPS). The microstructure exhibited by large amounts of ferromagnetic (FM) Fe3Si particles dispersed within the e-Cu matrix in the upper layer, and many e-Cu particles embedded within the FM Fe3Si matrix in the lower layer. The microhardness values of the Fe3Si matrix lower layer (758HV0.2) and e-Cu matrix upper layer (248HV0.2) were ∼7.3 and ∼2.4 times higher than that of pure copper by LIHC, respectively, indicating that the immiscible composite exhibited strongly inhomogeneous characteristics consistent with a “bilayer structure”. Moreover, the immiscible composite showed a high saturation magnetization of 96.2 emu/g and a low coercivity of 7.24 Oe due to the formation of FM Fe3Si with micro- and nanoscaled structures.

Metastable cellular structures (MCSs) play a crucial role for the mechanical performance in concentrated alloys during non-equilibrium solidification process. In this paper, typifying the heterogeneous 316L stainless steel by laser additive manufacturing (LAM) process, we examine the microstructures in cellular interiors and cellular boundaries in detail, and reveal the interactions of dislocations and twins with cellular boundaries. Highly ordered coherent precipitates present along the cellular boundary, resulting from spinodal decomposition by local chemical fluctuation. The co-existences of precipitates and high density of tangled dislocations at cellular boundaries serve as walls for extra hardening. Furthermore, local chemical fluctuation in MCSs inducing variation in stacking fault energy is another important factor for ductility enhancement. These findings shed light on possible routines to further alter nanostructures, including precipitates and dislocation structures, by tailoring local chemistry in MCSs during LAM.

In this paper, we designed a triboelectric acceleration sensor with excellent multiple parameters. To more easily detect weak vibrations, the sensor was founded on a multilayer suspension structure. To effectively improve the electrical properties of the sensor, a surface roughening and internal doping friction film, which was refined with a room temperature vulcanized silicone rubber (RTV) and some thermoplastic polyurethanes (TPU) powder in a certain proportion, was integrated into the structure. It was found that the optimization of the RTV film increases the open circuit voltage and short circuit current of the triboelectric nanogenerator (TENG) by 223% and 227%, respectively. When the external vibration acceleration is less than 4 m/s2, the sensitivity and linearity are 1.996 V/(m/s2) and 0.999, respectively. Additionally, when it is in the range between 4 m/s2 and 15 m/s2, those are 23.082 V/(m/s2) and 0.975, respectively. Furthermore, the sensor was placed in a simulated truck vibration environment, and its self-powered monitoring ability validated by experiments in real time. The results show that the designed sensor has strong practical value in the field of monitoring mechanical vibration acceleration.

The lack of highly efficient and stable electrocatalysts for oxygen reduction reaction (ORR) has been hindering the advances in proton exchange membrane fuel cells (PEMFCs). Harnessing the strong metal–support interactions (SMSI) effects at the interface between a metal oxide and a noble metal is one approach investigated to address these issues. In this work, TiO2 coating with 0.6 nm in thickness, uniformly formed on the entire surface of a carbon material is synthesized by a sonochemical reaction method. Deposition of Pt nanoparticles (NPs) on TiO2 coated carbon (TiO2/C) produces Pt/TiO2/C catalysts with enhanced activity and durability for ORR. Pt/TiO2/C(U) whose Pt NPs are formed by sonochemical reaction shows mass activity (MA) and specific activity (SA) 2.9 and 2.6 times, respectively, higher than Pt/C catalyst. More importantly, Pt/TiO2/C(U) catalyst exhibits a superior long-term durability. After 50,000 cycles of durability test, it retains 51.4 %/61.3% of initial MA/SA. Pt/TiO2/C(R) whose Pt NPs are formed by chemical reduction also shows enhanced activity and durability than Pt/C, but with less extents than Pt/TiO2/C(U). The significantly enhanced ORR performance of Pt/TiO2/C catalysts is attributed to the SMSI effect between TiO2 coating and Pt NPs plus bifunctional mechanism from the TiO2 surface around Pt NPs. The enhance durability can be explained as the protection of carbon by chemically inert TiO2 coating.

Objective To investigate the efficacy and safety of rituximab (RTX) as first-line treatment of acquired thrombotic thrombocytopenic purpura (aTTP). Methods Twenty-five patients with acute aTTP and/or severe a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13) deficiency were admitted to our centre from April 2009 to March 2015. Fourteen patients received RTX plus standard therapy (plasma exchange and corticosteroids) at acute episodes. Haemoglobin, platelet count, schistocytes, lactate dehydrogenase levels, ADAMTS13 activity and its inhibitors, and the ratio of B lymphocytes in the peripheral blood, were monitored. The number of plasma exchange (PEXs), total plasma volume, remission time, relapse ratio, and adverse effects were recorded. Results The median number of PEXs was 5 (2–17) sessions and median total plasma volume was 168.43 ml/kg (62.86–469.52 ml/kg). Patients achieved haematological remission at a median of 15 days (5–22 days), and the median time of immunological remission was 2 weeks (2–8 weeks) with a median follow-up of 13 months (3–61 months). ADAMTS13 activity significantly increased after 2 weeks. The B lymphocyte percentage in peripheral blood was reduced 1 week after the first dose of RTX infusion compared with before treatment (2.21% ± 5.23% vs 18.47% ± 7.34%, P = 0.000 [the result of statistical software]), and began to gradually increase 9 months later. Severe adverse effects and relapsing TTP were not observed during therapy and follow-up. However, one patient who had sustained immunological remission died of severe pneumonia 7 months later. Conclusion Although our study was limited by its small sample number and it was a non-controlled, clinical trial, it showed potential benefits of RTX therapy for acute aTTP. RTX may be administered as a first-line therapy for lowering patients’ relapse rate in the long term. Randomized, controlled trials of RTX for aTTP are required.

Chitosan/polycaprolactam (PA6) nanofibrous filter paper (NFP) was prepared by electrospinning technique. Characterization with Fourier transformation infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) indicated that there was weak interaction (hydrogen bonds) between PA6 and chitosan, and the average diameter of the composite nanofibers decreased as the chitosan content was increased. The maximum adsorption capacity of Cr(VI) on the NFP via filtration (114.7 mg g−1) was much higher than that via static adsorption (81.7 mg g−1) and shaking adsorption (80.7 mg g−1). Because the Cr(VI)-containing solution was forced to flow through the whole membrane in filtration, the chelation sites inside the membrane could be exploited, leading to the enhancement of the Cr(VI) adsorption. The hydrogen bonds between chitosan and PA6 could enhance the mechanical strength and the acid fastness of the NFP. Therefore, the NFP desorbed by H2SO4 can be well reinstated, and the adsorption capacity of Cr(VI) decreased slightly (only 17.9%) after three filtration cycles. On the basis of X-ray photoelectron spectroscopy (XPS) analysis, the possible mechanism for the Cr(VI) removal was that Cr(VI) was initially adsorbed on the NFP due to the electrostatic attraction, and subsequently reduced to the less toxic form Cr(III) by the amino groups of chitosan.

Chitosan/polymethylmethacrylate (PMMA) composite nanofibrous membrane was prepared by electrospinning technique with a single solvent system. Characterization with Fourier transformation infrared spectroscopy (FT-IR) indicated that there was weak interaction (such as hydrogen bonds) between PMMA and chitosan. Scanning electron microscopy (SEM) measurements illustrated that the average diameter of the composite nanofibers decreased as the chitosan content was increased, while the number of nano/micrometer sized beads increased in the membrane. The composite nanofibrous membrane with chitosan:PMMA ratio of 0.3:1.0 exhibited a maximum adsorption capacity (67.0 mg g(-1)) of Cr(VI) in static adsorption, which was nearly three times higher than that of chitosan powder (22.9 mg g(-1)). The adsorption capacity of Cr(VI) via filtration became even higher, where the maximum value was 92.5 mg g(-1) at pH 3.0. Notably, most of Cr(VI) has been removed after the first filtration at all pH values (2.0-6.0) investigated in this report. The adsorption capacity of the composite nanofibrous membrane decreased slightly (17.1%) after three filtration cycles even with the solution of pH 2.0, which shall be attributed to the enhanced mechanical strength and acid fastness of the composite membrane. X-ray photoelectron spectroscopy (XPS) analysis indicated that amino groups played an important role in the adsorption of Cr(VI).

To obtain a self-disinfecting surface to combat nosocomial infections, in situ synthesis of the MoO3-SiO2-Ag2O nanocomposite antibacterial coating was prepared onto Ti–6Al–4V substrate via a double cathode glow discharge technique conducted in a Ar + O2 gas mixture. The phase composition, microstructure and chemical structure of the as-prepared coating were systematically characterized by means of a series of microscopic examination methods. The microstructure of the coating exhibited an amorphous/nanocrystalline architecture, and both the MoO3 and Ag2O crystallites were evenly embedded in an amorphous SiO2 matrix. Photocatalytic activities of the coating were evaluated by photodegradation of rhodamine B (RhB) dye. The results showed that the introduction of Ag2O enhanced photocatalytic activity of the MoO3-SiO2 nanocomposite coating. In vitro antibacterial activity of the MoO3-SiO2-Ag2O coating against Gram-negative bacteria, Gram-positive bacteria and fungi were investigated and compared with that of the MoO3-SiO2 coating under both dark and visible light conditions. The MoO3-SiO2-Ag2O coating possessed higher bactericidal activities than the MoO3-SiO2 coating, due to the combined effects of surface hydrophobicity, the release of Ag+ ions, surface acidic reaction and photocatalytic activity.

In article number 2000532, Jixi Li and co‐workers report a set of four crystal structures of human RNA helicase DDX21, revealing dramatic conformational rearrangements during the RNA unwinding cycle. Furthermore, the discovery of small RNAs modulating the interaction between DDX21 and viral protein NS1, generates a fresh perspective toward the virus–host interface, and will be beneficial in developing therapeutics to combat the influenza virus infection. [Image: see text]

The human archease, hereafter named HArch, is identified as a key cofactor of the tRNA-splicing ligase complex, and a potential therapeutic target for treating nervous system injuries. However, little is known about the structural basis of HArch in tRNA maturation, mRNA splicing, and RNA repair. Here we report the crystal structures of HArch and its two mutants D51A and D178A with resolutions ranging from 1.96 Å to 3.4 Å. HArch is composed of an extended N-terminal protrusion domain (NTD) and one compacted C-terminal domain (CTD). Unlike previously reported homologous proteins, the NTD of the first subunit interacts with the CTD of the second one, and this interaction might be important for maintaining protein stability. Moreover, HArch interacts and colocalizes with RNA ligase RTCB in cells. Our current study reveals the atomic structure of HArch and may help us understand its function in mRNA splicing.

Background: Anti-infective treatment has become troublesome owing to aggravated resistance to antibacterial agents. Objectives: This study aimed at investigating the distribution characteristics and drug resistance changes of pathogenic bacteria in cerebrospinal fluid (CSF) of patients with intracranial infection receiving neurosurgery, and to provide evidence for rational use of antibacterial agents. Methods: Bacteria were collected from CSF cultures of all patients receiving neurosurgery in the hospital of the current research, from January 2013 to December 2015, and the same types of strains cultured from each case during the same infection were combined. A hospital information system (HIS) was then used to analyze the data of 120 patients, who received neurosurgery from January 2015 to June 2016 and had positive CSF bacterial culture results after surgery, and to treat them by rationally selecting antibacterial agents. Results: A total of 845 pathogenic bacterial strains were isolated from the CSF samples and cultured, of which 629 were Gram-negative bacteria, accounting for 74.4%. Particularly, Acinetobacter baumannii had severe pan-resistance. There were 216 Gram-positive bacteria, which accounted for 25.6% of all strains, and were mainly methicillin-resistant staphylococci, being basically resistant to penicillins and only susceptible to vancomycin and linezolid. After rational selection of antibacterial agents using HIS, based on the retrospective analysis results, 101 of the 120 patients were cured by vancomycin and linezolid (cure rate: 84.17%). Conclusions: Since the treatment outcomes after rational selection of antibacterial agents (i.e. vancomycin and linezolid) using HIS were satisfactory, the findings of retrospective analysis are of high clinical value.

A ZrC nanocrystalline coating is engineered onto a Ti-6Al-4V substrate using a double cathode glow discharge technique in order to improve the corrosion resistance and long-term stability of this alloy. The new coating exhibits an extremely dense, homogeneous microstructure composed of equiaxed grains with an average grain size of similar to 12 nm and is well adhered on the surface of the substrate. The corrosion behaviour of the coating is systematically investigated using various electrochemical methods, including potentiodynamic, potentiostatic polarizations and electrochemical impedance spectroscopy (EIS), in a simulated polymer electrolyte membrane fuel cell (PEMFC) operating circumstances under different temperatures. The results show that with rising temperature, the corrosion potential (E-corr) decreases and the corrosion current density (i(corr)) of the ZrC coated specimen increases, indicating that the corrosion resistance decreased with increasing temperature. However, at a given temperature, the ZrC-coated Ti-6Al-4V alloy has a higher E-corr and lower icorr as compared to the bare substrate. The results of EIS measurements show that the values of the resistance for the ZrC coated Ti-6Al-4V alloy are three orders of magnitude larger than those of Ti-6Al-4V in the simulated PEMFC environment. (C) 2015 Elsevier B.V. All rights reserved.

We investigated the synthesis of quasi-two-dimensional carbide (Ti 3 C 2 ), with the name of MXene, by immersing Ti 3 AlC 2 in 40% or 49% hydrofluoric acid (HF) at 0 °C, 15 °C or 60 °C. The influences of time, temperature, and source of Ti 3 AlC 2 on the synthesis were researched. It was found that Ti 3 C 2 synthesized from pressureless synthesized Ti 3 AlC 2 was highly oriented compared to that from hot-pressed Ti 3 AlC 2 . As-synthesized Ti 3 C 2 could be further exfoliated by intercalation with urea, dimethylsulfoxide or ammonia. From the results of thermogravimetry and differential scanning calorimetry, Ti 3 C 2 MXene with F/OH termination was found to be stable in argon atmosphere at temperature up to 800 °C. In oxygen atmosphere, at 200 °C, parts of MXene layers were oxidized to obtain an interesting structure: anatase nano-crystals were evenly distributed on 2D Ti 3 C 2 layers. At 1000 °C, MXene layers were completely oxidized and anatase phase fully transformed to rutile in oxygen atmosphere.

In order to explore the effects of Cr alloying on the wear and oxidation resistance of MoSi2 films, four kinds of (Mo1-xCrx)Si-2 (x=0, 0.05, 0.10 and 0.15) nanocrystalline films of differing Cr contents were fabricated onto Ti6Al4V substrates by a double cathode glow discharge apparatus. The microstructure features of the as-deposited films were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The hardness and elastic modulus of the (Mo1-xCrx)Si-2 nanocrystalline films were evaluated by nano-indentation. The dry sliding wear properties of the as-deposited films sliding against GCr15 rolling bearing steel were studied using a ball-on-disc type tribometer at room temperature. The results showed that the friction coefficients and specific wear rates of the (Mo1-xCrx)Si-2 nanocrystalline films decreased with increasing Cr content in the films. The oxidation behavior of the (Mo1-xCrx)Si-2 nanocrystalline films was investigated at 500 degrees C under cyclic oxidation conditions in air for exposure time of 100 h. The oxidation kinetics of the films was found to obey a subparabolic behavior, and three Cr-containing MoSi2 films showed a much lower weight gain and the oxidation rate constant as compared to the monolithic MoSi2 film during a 100 h exposure. Surface morphologies, phase constituents and electrochemical behavior of the oxide scales formed on the (Mo1-xCrx)Si-2 nanocrystalline films were characterized using FESEM, XRD and electrochemical-impedance spectroscopy (EIS). The electrochemical results revealed that the structure of the oxide scales changed from a homogeneous and dense structure to a duplex structure consisting of a porous outer layer and a denser inner layer. The overall resistance of the oxide scales depended strongly on both the oxidation time and Cr content in the films. (C) 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

Altererythrobacter epoxidivorans CGMCC 1.7731(T) is a Gram-negative bacterium isolated from marine sediments. It is able to utilize benzo[a]pyrene as sole carbon and energy source. Here, we describe the complete genome sequence and annotation of A. epoxidivorans CGMCC 1.7731(T). The genome has a size of 2,786,256 bp (61.50 mol% G+C content), which consists of 2773 coding genes, 43 tRNA genes and 3 rRNA genes. According to the genome information, strain A. epoxidivorans CGMCC 1.7731(T) encodes 22 genes related to degradation of benzo[a]pyrene. These genes may have potential in bioremediation of PAH-polluted environments.

Two-dimensional (2D) Ti3C2 was synthesized by the exfoliation of Ti3AlC2 with HF solution and subsequently intercalation with dimethyl sulfoxide. As anode for lithium ion batteries, Ti3C2 after intercalation had an obvious higher capacity than that before intercalation. The capacity can be 123.6 mAh g−1 at 1C rate with a coulombic efficiency of 47%. It is higher than that of 2D Ti2C and close to the theoretical capacity of Ti3C2 with F termination. It was suggested that MXene with pure F groups may be a way to further improve its Li storage performance. Keywords: MXene, Li-ion batteries, Anode materials, Two-dimensional materials

MXenes are novel graphene-like 2-D materials. Cu2O is an effective additive for thermal decomposition of ammonium perchlorate (AP). We reported the synthesis of MXene (Ti3C2), Cu2O and MXene-Cu2O respectively. The samples were characterized by means of X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). Results indicate that the MXene is composed of lots of nano-sheets and the thickness is 30 ± 10 nm, and Cu2O nanoparticles nucleate and grow heterogeneously directly on the surface of MXene. The effect of these MXene, Cu2O and MXene-Cu2O samples on the thermal decomposition of AP were investigated using TG-DSC. The results revealed that MXene-Cu2O have a great influence on the thermal decomposition of AP than that of pure MXene and Cu2O.

In this paper, synthesis of novel super hard and high performance composites of titanium silicon carbide–cubic boron nitride (Ti3SiC2–cBN) was evaluated at three different conditions: (a) high pressure synthesis at ~ 4.5 GPa, (b) hot pressing at ~ 35 MPa, and (c) sintering under ambient pressure (0.1 MPa) in a tube furnace. From the analysis of experimental results, the authors report that the novel Ti3SiC2–cBN composites can be successfully fabricated at 1050 °C under a pressure of ~ 4.5 GPa from the mixture of Ti3SiC2 powders and cBN powders. The subsequent analysis of the microstructure and hardness studies indicates that these composites are promising candidates for super hard materials.

A two-dimensional (2D) cellular automaton (CA)-finite difference method (FDM) model is proposed to simulate the dendrite growth and microporosity formation during solidification of aluminum alloys. The model involves a three-phase system of liquid, gas, and solid. The growth of both dendrite and gas pore is simulated using a CA approach. The diffusion of solute and hydrogen is calculated using the FDM. The model is applied to simulate the formation and interactions of dendrites and micropores in an Al-7wt.%Si alloy. The effects of initial hydrogen concentration and cooling rate on microporosity formation are investigated. It is found that the porosity nuclei with larger size grow preferentially, while the growth of the small porosity nuclei is restrained. The competitive growth between porosities and dendrites is also observed. With the increase of initial hydrogen concentration, the incubation time of porosity nucleation and growth decreases, and the percentage of porosity increases, while porosity density does not increase apparently. With the decrease of cooling rate, porosity nucleates and starts to grow at higher temperatures, and the percentage of porosity increases, but the porosity density displays a decreasing trend. In addition, at a slower cooling rate, the competitive growth between porosities and dendrites becomes more evident, leading to a more non-uniform distribution of porosity size, and an increased maximum porosity size. The simulation results agree reasonably with the experimental data in the literature.

In this paper, novel Nb-containing Ti5Si3 (i.e., Ti56.2Nb6.3Si37.5 and Ti50.0Nb12.5Si37.5) nanocrystalline coatings were deposited onto Ti-6Al-4V substrates by a double glow discharge plasma technique. The effects of Nb alloying on the electrochemical behavior of the Ti5Si3 nanocrystalline coatings were systematically investigated in a naturally aerated 5 wt.% H2SO4 solution, for which various electrochemical techniques, including potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), potentiostatic polarization and Mott-Schottky analysis, were employed. Moreover, to evaluate the corrosion performance of the as-deposited coatings over an extended period, their corrosion resistance was analyzed after 7 days' immersion in a 5 wt.% H2SO4 solution by EIS measurements and observations of corroded surface morphologies. The results showed that the Ti62.5-xNbxSi37.5(x = 0, 6.3, 12.5) nanocrystalline coatings exhibit superior corrosion resistance compared with Ti-6Al-4V, and their corrosion resistance is enhanced with increasing Nb content, suggesting that Nb alloying is an effective strategy for improving the corrosion protection ability of the Ti5Si3 nanocrystalline coating. The roles of Nb additions in enhancing the corrosion resistance of the Ti5Si3 nanocrystalline coatings can be summarized as: (a) reducing the residual tensile stresses of the as-deposited coatings and (b) tailoring the composition, compactness and electronic structure of the passive films formed. These findings are expected to broaden the application of Ti5Si3 as a highly corrosion-resistant coating for engineering components operating under aggressive conditions.

To explore the influence of Al alloying on the oxidation resistance of MoSi2, four Mo(Si1−xAlx)2 nanocrystalline films, with differing Al contents, were fabricated on Ti–6A1–4V substrates by a double-cathode glow discharge technique and their cyclic oxidation behavior was characterized at 500 °C in air. The oxidation kinetics of the four Mo(Si1−xAlx)2 films was found to obey a subparabolic behavior with respect to the overall exposure, and their oxidation resistance was improved by Al additions. On the other hand, the electrochemical behavior of the oxide scales developed on the four Mo(Si1−xAlx)2 nanocrystalline films in a 3.5 wt% NaCl solution was studied using electrochemical-impedance spectroscopy (EIS). The impedance data showed that with increasing oxidation time, the oxide scales transformed from a homogeneous and dense structure to a duplex structure consisting of a porous outer layer and a denser inner layer. The resistance of the oxide scales increased with increasing Al addition, implying an enhanced protective ability of the oxide scales by Al alloying in media containing chlorine ions. The findings represent a step forward in improving the surface integrity of alloy components used in the hot zones of jet engines.

Bioactive compounds such as phenols and phytic acid in wheat contribute to antioxidant capacities. (1) Background: Prior studies drew a general conclusion that the environment affected bioactive compounds greatly, but how the single environmental factor affects these characteristics remains unclear. (2) Methods: We conducted that twenty-eight winter wheat genotypes were grown in replicated trials at seven locations in China for two consecutive years and subdivided the environmental factor into five soil factors and six meteorological factors to evaluate the impact on the antioxidant capabilities and bioactive compounds contents of wheat grains by using principal component analysis (PCA). RT-PCR was used to identify gene expression of bioactive compounds under different conditions. (3) Results: Temperature affects bioactive compounds contents and antioxidant capacities greatly in wheat grains. Accumulation time, daylight length, and daily maximum temperature showed a high correlation with bioactive compounds contents and antioxidant capacities, especially in the vegetative growth phase. The gene TaMIPs related to phytic acid and TaPAL1, TaC3H1, TaC4H, Ta4CL1, and TaCOMT1 related to total phenolics had higher gene expression level with larger temperature differences in wheat grains. (4) Conclusions: The planting locations with higher temperatures and longer daylight length could produce higher contents of bioactive compounds and antioxidant capacities and the cooler temperatures of a planting location might produce wheat grains with lower phytic acid contents in wheat grains.

TiO2/Ti3C2 nanocomposites with high photocatalytic activity were successfully fabricated via a hydrothermal process. The microstructure and phase composition of these composites were characterized by field emission scanning electron microscope (FESEM) and X-ray diffraction (XRD). The photocatalytic performance of pure TiO2 and TiO2/Ti3C2 nanocomposites were evaluated by photodegradation of methyl orange (MO) under ultraviolet light irradiation. Photodegradation tests results revealed that TiO2/Ti3C2 have much better photocatalytic activity than pure TiO2 nanomaterials. And it was suggested that the TiO2/Ti3C2 exhibited more effective electron–hole separation than pure TiO2 and Ti3C2 under UV light irradiation.

Flower-like BiOCl and Ag–BiOCl nanocomposite have been successfully fabricated via a microwave irradiation process. The structure and morphology of the samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM). The photocatalytic property of the BiOCl and Ag–BiOCl nanocomposite was evaluated by photodegradation of Rhodamine B (RhB) under visible light illumination. Results of photodegradation tests reveal that the Ag–BiOCl nanocomposite has much better photocatalytic activity than pure BiOCl. The excellent photocatalytic activity can be ascribed to the high effective electron–hole separation which results in the significant improvement of the photocatalytic activity of BiOCl.

Titanium aluminum carbide (Ti3AlC2 and Ti2AlC) powders were synthesized from TiH2 powders instead of Ti powders as Ti source by a tube furnace under argon atmosphere without preliminary dehydrogenation. 95 wt% pure Ti3AlC2 powders were synthesized from TiH2/1.1Al/2TiC at 1 450 °C for 120 min. High-purity Ti2AlC powders were also prepared from 3TiH2/1.5Al/C and 2TiH2/1.5Al/TiC powders at 1 400 °C for 120 min. The as-synthesized samples were porous and easy to be ground into powders. Sn or Si additives in starting materials increased the purity of synthesized Ti3AlC2 obviously and expanded the temperature range for the synthesis of Ti3AlC2. With Si or Sn as additives, high pure Ti3AlC2 was synthesized at 1 200 °C for 60 min from TiH2/x Si/Al/2TiC and TiH2/x Sn/Al/2TiC (x = 0.1, 0.2), respectively.

Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) is believed to be associated with aggressive periodontitis characterized by a rapid bone loss. A. actinomycetemcomitans lipopolysaccharide (LPS) has a similar structure to Escherichia coli LPS, and they are Toll-like receptor 4 agonists. Bone sialoprotein (BSP) is an early marker of osteoblast differentiation. To investigate the effects of A. actinomycetemcomitans LPS on bone formation, we targeted BSP as a marker for osteogenic differentiation and bone formation. BSP mRNA levels were decreased by 0.1 µg/ml and increased by 0.01 µg/ml A. actinomycetemcomitans LPS at 6 h in osteoblast-like ROS17/2.8 cells. In transient transfection analyses, 0.1 µg/ml decreased and 0.01 µg/ml A. actinomycetemcomitans LPS increased luciferase activities of the construct (−116 to +60). Introduction of 2 bp mutations to the constructs showed that the effects of A. actinomycetemcomitans LPS were mediated by a cAMP response element (CRE), a FGF2 response element (FRE), and a homeodomain protein-binding site (HOX). Tyrosine kinase, ERK1/2, and PI3-kinase/Akt participated in the effects of both 0.1 and 0.01 µg/ml A. actinomycetemcomitans LPS. The results of gel shift showed that 0.1 µg/ml decreased while 0.01 µg/ml A. actinomycetemcomitans LPS increased CRE-, FRE-, and HOX-binding protein complexes formation at 6 h, and revealed that 0.01 µg/ml A. actinomycetemcomitans LPS induced BSP transcription through CREB1, JunD, Fra2, c-Fos, Runx2, Dlx5, and Smad1 targeting those response elements. These studies therefore indicated that 0.1 µg/ml suppressed and 0.01 µg/ml A. actinomycetemcomitans LPS increased BSP gene transcription mediated through CRE, FRE, and HOX elements in the rat BSP gene promoter. J. Cell. Biochem. 113: 2822–2834, 2012. © 2012 Wiley Periodicals, Inc.

Hierarchical ZnO and Ag doped ZnO nanostructures have been successfully fabricated on a large scale using zinc acetate and silver nitrate as starting reactants via a microwave-assisted process. The structural and morphologies of the samples were characterized by X-ray diffraction, field emission scanning electron microscope and X-ray photoelectron spectroscopy. The photocatalytic property of the Ag/ZnO heterostructures is evaluated by photodegradation of Rhodamine B (RhB) under UV–vis illumination. Results of photodegradation tests reveal that the Ag doped hierarchical ZnO microspheres show much better photocatalytic activity than pure ZnO nanomaterials. The excellent photocatalytic activities can be ascribed to the high effective electron–hole separation which results in the significant improvement of the photocatalytic activity of ZnO.

Bone sialoprotein (BSP) is a noncollagenous protein of the extracellular matrix in mineralized connective tissues that has been implicated in the nucleation of hydroxyapatite. Forskolin (FSK), an activator of adenylate cyclase, increased the intracellular cAMP level, which stimulates the proliferation and differentiation of osteoblasts. Fibroblast growth factor 2 (FGF2) is a potent mitogen in many cell types, including osteoblasts. In human prostate cancer DU145 cells, FSK (1 μM) and FGF2 (10 ng/ml) increased BSP and Runx2 mRNA and protein levels at 3 and 12h, respectively. Transient transfection analyses were performed using chimeric constructs of the human BSP gene promoter linked to a luciferase reporter gene. Treatment of DU145 cells with FSK (1 μM) and FGF2 (10 ng/ml) increased the luciferase activities of constructs between -60LUC to -927LUC and -108LUC to -927LUC, including the human BSP gene promoter. Effects of FSK and FGF2 abrogated in constructs included 2bp mutations in the two cAMP response elements (CRE1 and CRE2). Luciferase activities induced by FSK and FGF2 were blocked by protein kinase A and tyrosine kinase inhibitors. Gel mobility shift analyses showed that FSK and FGF2 increased the binding of CRE1 and CRE2. CRE1-protein complexes were supershifted by phospho-CREB1 and c-Fos antibodies, and disrupted by CREB1, c-Jun, JunD, Fra2, p300, Runx2, Dlx5 and Smad1 antibodies. CRE2-protein complexes were disrupted by CREB1, phospho-CREB1, c-Fos, c-Jun, JunD, Fra2, p300, Runx2, Dlx5 and Smad1 antibodies. These studies demonstrate that FSK and FGF2 stimulate BSP transcription in DU145 human prostate cancer cells by targeting the CRE1 and CRE2 elements in the human BSP gene promoter.

Kaempferol is a typical flavonol-type flavonoid that is present in a variety of vegetables and fruits, and has a protective effect on postmenopausal bone loss. Bone sialoprotein (BSP) is thought to function in the initial mineralization of bone and could be crucial for osteoblast differentiation, bone matrix mineralization and tumor metastasis. In the present study we investigated the regulation of BSP transcription by kaempferol in rat osteoblast-like UMR106 cells, and the effect of kaempferol on new bone formation. Kaempferol (5 microM) increased BSP and Osterix mRNA levels at 12 h and up-regulated Runx2 mRNA expression at 6 h. Kaempferol increased luciferase activity of the construct pLUC3, which including the promoter sequence between nucleotides -116 to +60. Transcriptional stimulation by kaempferol abrogated in constructs included 2 bp mutations in the inverted CCAAT, CRE, and FRE elements. Gel shift analyses showed that kaempferol increased nuclear protein binding to CRE and FRE elements, whereas the CCAAT-protein complex did not change after kaempferol stimulation. Twelve daily injections of 5 microM kaempferol directly into the periosteum of parietal bones of newborn rats increased new bone formation. These data suggest that kaempferol increased BSP gene transcription mediated through inverted CCAAT, CRE, and FRE elements in the rat BSP gene promoter, and could induce osteoblast activities in the early stage of bone formation.

Lipopolysaccharide (LPS) is a major mediator of inflammatory response. Periodontopathic bacterium Porphyromonas gingivalis LPS has quite different character from Escherichia coli LPS. E. coli LPS is agonist for Toll-like receptor 4 (TLR4), whereas P. gingivalis LPS worked as antagonist for TLR4. Bone sialoprotein (BSP) is an early marker of osteoblast differentiation. To investigate the effects of P. gingivalis LPS on BSP transcription, we used rat osteoblast-like ROS17/2.8 cells. BSP mRNA levels were decreased by 0.1 microg/ml and increased by 0.01 microg/ml P. gingivalis LPS at 12 h. Results of luciferase assays showed that 0.1 microg/ml decreased and 0.01 microg/ml P. gingivalis LPS increased BSP transcription in -116 to +60 BSP construct. The effects of P. gingivalis LPS were abrogated by double mutations in cAMP response element (CRE) and FGF2 response element (FRE). Tyrosine kinase inhibitor herbimycin A, ERK1/2 inhibitor and antioxidant N-acetylcystein inhibited effects of P. gingivalis LPS. Protein kinase A inhibitor and PI3-kinase/Akt inhibitor only abolished the effect of 0.01 microg/ml P. gingivalis LPS. Furthermore, 0.1 microg/ml LPS decreased the CRE- and FRE-protein complexes formation, whereas 0.01 microg/ml P. gingivalis LPS increased the nuclear protein binding to CRE and FRE. ChIP assays revealed increased binding of CREB1, JunD, Fra2, Runx2, Dlx5, and Smad1 to a chromatin fragment containing the CRE and FRE by 0.01 microg/ml P. gingivalis LPS. These studies therefore indicated that 0.1 microg/ml suppressed, and 0.01 microg/ml P. gingivalis LPS increased BSP gene transcription mediated through CRE and FRE elements in the rat BSP gene promoter.

The aluminum matrix composite (AMC) coating reinforced with TiB was prepared utilizing in situ synthesized technique by laser cladding. Microstructural characterization and dry sliding wear behavior of in situ TiB/Al metal matrix composite were studied by SEM, XRD, TEM and Pin-on-disc friction and wear tester. The phase structure of the composite coating consists of α-Al, TiB, Al3Ti and Al3Fe. It has been found that the shape of in situ synthesized TiB is mainly taken on micro-magnitude lump and nano-magnitude whisker. Owing to B27 structure of TiB, the TiB has an anisotropy axis of growth, which results in the TiB strip and whisker preferring grown along [0 1 0] direction. It is worth to notice that the novel microstructure inside of TiB is particle and strip Al5Fe2 phase and definite crystallographic relationship between the Al5Fe2 phase and TiB has been determined by selected area diffraction pattern. The wear tests results show that the composite coatings can only improve wear resistance at the lower applied load (below 26.7 N), but at higher applied load (26.7–35.6 N) the wear resistance behavior of the coating is worsened due to the fracture and pullout of reinforcement phase.

Butyric acid (sodium butyrate; BA) is an extracellular metabolite secreted from periodontopathic bacteria present in subgingival plaque. BA induces apoptosis of T and B cells, and acts as a potent inhibitor of histone deacetylases. Bone sialoprotein (BSP) is thought to function in the initial mineralization of bone, and may be crucial for osteoblast differentiation, bone matrix mineralization and tumor metastasis. In the present study we investigated the regulation of BSP transcription by BA in rat osteoblast-like ROS17/2.8 cells. At 12 h, BA (10 -4 M) increased the level of BSP mRNA, and enhanced the luciferase activity of the construct pLUC3, which includes the promoter sequence between nucleotides -116 and +60. Transcriptional stimulation by BA was abrogated in the pLUC3 construct which containing a 2-bp mutation in the fibroblast growth factor 2 response element (FRE). Gel shift analyses showed that BA increased the binding of nuclear protein to FRE. These data suggest that BA increases the transcription of the BSP gene mediated through FRE in the rat BSP gene promoter, and induces osteoblast activity in the early stage of bone formation. (J Oral Sci 52, 231-237, 2010)