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Chinese Nuo mask is made up of wooden substrate and colorful paint, in which wooden substrate exhibits high hydrophilicity and paint cannot show a hydrophobicity. To achieve long-term non-destructive hydrophobic protection of Nuo mask surface, here, epoxy-based nanohybrid coatings were prepared. Poly(glycidyl methacrylate) (PGMA) matrix was used for strong interfacial adhesion and good transparency. Silica nanofiller was used for good weather resistance and high surface roughness. Here, PGMA/silica composite coatings on Nuo mask surfaces were prepared. The reduced water wettability and well-maintained color of coating/mask composite surfaces were verified. Strong abrasion and ultraviolet (UV) resistances of optimal coating/mask composite surface were found. Optimal PGMA/silica composite (2 wt% silica) has high light transmittance (> 89%), and hydrophobicity is achieved on optimal coating/mask composite surface with water static contact angle (SCA) of 93.1° ± 1.1°. This surface displays color difference (ΔE) of 1.9 ± 0.1. This surface after 50 abrasion cycles (ΔE of 2.4 ± 0.1) still exhibits higher SCA (65.5° ± 1.1°) than untreated Nuo mask surface without abrasion (~ 32°). This surface after 24 h of UV exposure possesses SCA of 85.2° ± 1.3° with ΔE of 0.2 ± 0.1. This work enables long-lasting hydrophobic protection of traditional mask surfaces. [ABSTRACT FROM AUTHOR]

Cool linen is used to produce summer clothing to be known as summer cloth. Nevertheless, ramie-fiber surfaces bear hydrophilic hydroxyls to result in rainwater wetting and stain adhering. To achieve outdoor application of summer cloth, here, light all-organic hydrophobic copolymer coatings were formed on surfaces of two various summer clothes. First, atom transfer radical polymerization was utilized to synthesize polydimethylsiloxane-block-polymethacryloxypropyl trimethoxysilane. Then, neat copolymer films and copolymer coating/cloth complexes were prepared. Coating/cloth complexes were characterized. Finally, hydrophobicity-induced antifouling properties of complexes were confirmed, followed by justifying good resistance to surface abrasion for coating/compact summer cloth complex with superhydrophobicity. As a result, the optimal coating/compact summer cloth complex can fight against ink pollution and exhibit a water contact angle of 150.3 degrees after 200 abrasion cycles, in which neat copolymer film has a light transmittance of ~ 90% based on 30 min of pre-hydrolysis. Superhydrophobicity is ascribed to silicon surface enriching-induced low surface energy as well as surface micro-/nano-binary composite rough structure. This work has realized a controllable preparation of silicon-bearing copolymers with long-term hydrophobicity for protecting various summer clothes. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this retrospective observational study conducted in patients with hepatic impairment was to assess the variability of linezolid trough concentrations, to determine the risk factors for linezolid overexposure, and to investigate the effect of linezolid overexposure on linezolid-induced thrombocytopenia. Methods: All enrolled patients received a standard dose (600 mg every 12 h) of linezolid and underwent therapeutic drug monitoring. The Child–Pugh-Turcotte score was used to divide patients into three groups: mild, moderate, and severe hepatic impairment. The risk factors for linezolid overexposure (Cmin > 8 mg/L) and linezolid-induced thrombocytopenia were examined using logistic regression. And the Kaplan–Meier curve was used to describe the association between linezolid overexposure and linezolid-induced thrombocytopenia. Results: Seventy-seven patients were included, 37 (48.1%) of whom experienced linezolid overexposure. Patients with severe hepatic impairment had a substantially higher median Cmin of linezolid than those with mild (20.7 mg/L vs 5.51 mg/L, P < 0.001) or moderate (20.7 mg/L vs 6.70 mg/L, P = 0.001) hepatic impairment. Severe hepatic impairment was significantly associated with linezolid overexposure (OR 7.037, 95%CI 1.426–34.727, P = 0.017). After linezolid treatment, linezolid-induced thrombocytopenia occurred in 32 (41.6%) patients, and Cmin > 8 mg/L was a significant predictor of linezolid-induced thrombocytopenia (OR 3.024, 95%CI 1.083–8.541, P = 0.035). Conclusion: Patients with hepatic impairment who received standard doses of linezolid are at greater risk of linezolid overexposure, which may lead to a higher incidence of linezolid-induced thrombocytopenia. [ABSTRACT FROM AUTHOR]

In this research, ultrasonic nanocrystal surface modification (UNSM) was used to process a 7075-T651 aluminum alloy. After UNSM treatment, a work-hardened layer with compressive residual stress up to 500 MPa was generated on the near-surface region of the sample. The surface microhardness of the alloy was increased from 195 ± 4 to 225 ± 7 HV, and the surface roughness was decreased from 1.32 ± 0.04 to 0.54 ± 0.27 µm. The stress concentration factor Kt of the as-received specimen was decreased from 1.080 to 1.069 after UNSM processing. Rotating–bending fatigue tests showed that UNSM significantly improved the fatigue performance. In addition, UNSM-treated 7075-T651 samples were able to endure pitting corrosion in a 3.5 wt.% NaCl solution for 72 h without any degradation in fatigue performance. These results demonstrated that UNSM is a robust surface modification method that can improve the rotating–bending fatigue resistance of the aluminum alloy. [ABSTRACT FROM AUTHOR]

In this work, the nitriding efficiency in an ultrafine-grained iron was investigated. Prior to nitriding, the ultrasonic nanocrystalline surface modification (UNSM) technique was used to process the coarse-grained iron to obtain ultrafine-grained iron. Gas nitriding was conducted for the UNSM-treated iron and the coarse-grained iron at temperatures from 300 °C to 560 °C. The results indicate that the combination of UNSM and nitriding provide much higher efficiency for hardening than the sum of the efficiencies of UNSM alone and nitriding alone. Nitride nucleation was confirmed in the diffusion layer of the UNSM-treated iron following the nitriding process, enhancing the hardness after nitriding. X-ray diffraction patterns were obtained for both the UNSM-treated iron subjected to nitriding as well as iron that underwent only nitriding at different temperatures. It was also found that the minimum temperatures required to form nitrides, including γ′-Fe4N, ε-Fe3N, ε-Fe2N, and FeN, were reduced because of the high chemical potential at the grain boundaries. The theoretical analysis suggests that heterogeneous nitride nucleation at grain boundaries is the key factor that contributes to the enhancement in hardness in the nitriding layer in ultrafine-grained metals and nanocrystalline metals. [ABSTRACT FROM AUTHOR]

Background: Transgelin-2 is an actin-binding protein that is widely expressed in various tissues and organs of the body, and reportedly may participate in the development and progression of multiple cancers. However, the clinical significance of transgelin-2 still remains controversial. We, therefore, aimed to determine the expression of transgelin-2 in breast cancer as well as its correlation with the tumorigenesis, progression and prognosis of human breast cancer. Methods: We collected tissues of 58 breast cancer patients from our hospital and 1090 samples from The Cancer Genome Atlas (TCGA) database. X-tile software was used to divide the transgelin-2 mRNA expression level in the database, logistic regression model was used to identify independent factors influencing transgelin-2 mRNA expression, and then Cox regression and Kaplan–Meier analysis were used to find factors that influence survival of breast cancer. Results: Transgelin-2 was significantly overexpressed in breast cancer tissues from our hospital and receiver operating characteristic (ROC) curve indicated that transgelin-2 may have diagnostic value. Meanwhile, estrogen receptor (ER) was in inverse correlation with transgelin-2 protein and mRNA expression, and transgelin-2 expression was positively correlated with Ki67 in breast cancer tissues. Logistic regression model revealed that TNM stage, ER and progesterone receptor (PR) status were independent factors for transgelin-2 mRNA expression. Patients with high transgelin-2 mRNA expression showed a poor survival and the trend was statistically significant only in ER-negative patients. Conclusions: Transgelin-2 was expressed significantly higher in breast cancer cells and correlated with some clinicopathological factors. High transgelin-2 expression might predict poor prognosis for ER-negative patients. [ABSTRACT FROM AUTHOR]

Background Patients colonized with carbapenem-susceptible Pseudomonas aeruginosa (CSPA) strains upon admission to the intensive care unit (ICU) tend to be quickly followed by detected carbapenem-resistant P. aeruginosa strains after admission. Objective To assess the risk factors associated with the quick loss of carbapenem susceptibility and to identify time threshold of prior antimicrobial exposure for the loss during ICU stay. Setting A tertiary-care teaching hospital with 2560 beds located in the northwest region of China. Method A retrospective observational study was conducted between January 2013 and April 2016 at ICUs. Logistic regression analysis was used to assess risk factors, and receiver operating characteristic (ROC) analyses were constructed to identify the time threshold. Main outcome measure The time threshold and risk factors for the quick loss of carbapenem susceptibility. Results Among the 84 patients with CSPA initially, 32 (38.1%) patients were observed to have a loss of carbapenem susceptibility during ICU stay. Logistic regression analyses showed that previous carbapenem exposure was only independently associated with the loss of carbapenem susceptibility (odds ratio 13.16; 95% CI 3.13-55.24; p < 0.001). The optimal cut-off was 3.5 days on ROC curve, indicating the high risk for loss of susceptibility. Conclusion In order to alleviate selective pressure caused by antipseudomonal carbapenems exposure, continued research is needed to determine the most appropriate carbapenems treatment strategies. [ABSTRACT FROM AUTHOR]

This study evaluated the clinical and cost-effectiveness of prophylactic use of fluconazole versus mould-active triazoles (voriconazole and posaconazole) in adult patients with acute lymphoblastic leukemia (ALL). A decision analytical model was developed with inputs from a 7-year retrospective study (2009-2016) of 103 consecutive adult patients with ALL who received antifungal prophylaxis. Information on the administration of antifungal agents, clinical outcomes, and costs were collected. One-way sensitivity analyses and probabilistic sensitivity analysis were performed. The mould-active triazoles group was associated with higher life-years (3.71 vs 3.59) and lower total costs (US$4886 vs US$5722) per patient compared with fluconazole. One-way sensitivity analyses revealed that varying all of the key variables in the model did not affect the robustness of the results. Probabilistic sensitivity analysis demonstrated that mould-active triazoles had a probability of 77.1 and 90.1% of providing a dominant and cost-effective option relative to fluconazole, respectively. Mould-active triazoles should be regarded as preferable to fluconazole as the first-line prophylactic for adult patients with ALL accompanied by uncommon severe vinca alkaloid-induced neurotoxicity. However, the results reported here should be interpreted with caution owing to the observational nature of the data. [ABSTRACT FROM AUTHOR]

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for simultaneous determination of 5-aminoimidazole-4-carboxamide-1-β- d-ribofuranoside (AICA riboside) and its active metabolite 5-aminoimidazole-4-carboxamide-1-β- d-ribofuranotide (AICA ribotide) in mice plasma. Adenosine monophosphate was chosen as an internal standard, and plasma was deproteinized by adding 14% perchloric acid, and then, the resulting supernatant was diluted with water to decrease matrix effect. A 10 μL aliquot of the solution was injected into the LC-MS/MS system, and separation was achieved on a Gemini C-Phenyl column with a mobile phase composed of 0.1% formic acid (v/v) and methanol. A triple quadrupole mass spectrometer with an electrospray turbo ion source operating in multiple reaction monitoring (MRM) positive ion mode was used as detector. The precursor-product ion pairs for MRM were m/ z 259.2 → 110.1 and 259.2 → 242.1 for AICA riboside, 339.1 → 110.1 and 339.1 → 322.1 for AICA ribotide, and 348.3 → 136.0 and 348.3 → 119.1 for the internal standard, respectively. The total analytical run time was 10 min. The proposed method was linear over the range 0.01-10 μg/mL for AICA riboside and 0.01-5 μg/mL for AICA ribotide. The lower limit of quantification (LLOQ) was 10 ng/mL for both AICA riboside and AICA ribotide. The sensitivity, accuracy, and precision of this method were within acceptable limits during the validation period. The method was successfully applied to investigate the pharmacokinetics characteristics of AICA riboside and AICA ribotide in mice. [ABSTRACT FROM AUTHOR]

Purpose: The substantial variability in the antiplatelet efficacy of clopidogrel has raised major concerns. Molecular epidemiological research suggests that ABCB1 C3435T polymorphism may be associated with clopidogrel response, but results remain controversial. To derive a more precise evaluation of the associations between ABCB1 C3435T polymorphism and the clinical efficacy of clopidogrel, we have conducted a PRISMA-compliant meta-analysis. Methods: The PubMed and EMBASE databases were searched for eligible studies up to 25 October 2016. The odds ratio (OR), the standard mean difference (SMD) and 95% confidence interval (CI) were applied to assess the strength of the relationship. Results: Overall, 28 related studies involving 23,243 patients were analyzed. No association was found between the ABCB1 polymorphisms and the primary outcome. In the subgroup analysis, the C3435T mutation significantly reduced platelet activity as tested by the LTA assay in the dominant (SMD −0.140, 95% CI −0.272 to −0.009, P = 0.036) and heterozygous (SMD −0.154, 95% CI −0.290 to −0.017, P = 0.027) models, but the result lacked robustness in the sensitivity analysis. A significant association between the C3435T polymorphism and bleeding risk was also observed with low heterogeneity in the dominant (OR 1.805, 95% CI1.124-2.900, P =0.015, I = 0%), homozygous (OR 1.952, 95% CI 1.055-3.611, P = 0.033, I = 13.2%) and heterozygous (OR 1.793, 95% CI 1.091-2.946, P = 0.021, I = 0%) models in Asian patients. Conclusions: The results of the meta-analysis suggest that ABCB1 C3435T polymorphism may increase the risk of bleeding in Asian patients treated with clopidogrel. The implied relationship needs to be verified in future basic genetic pharmacology studies. [ABSTRACT FROM AUTHOR]

A series of 2-phenoxy-N-phenylacetamides were designed and synthesized with a view to develop novel anticancer agents. All compounds were prepared with varied substitutions in the phenyl ring of aniline and evaluated for their anticancer activity. The majority of them displayed a moderate degree of cytotoxicity against several human cancer cell lines. Six compounds displayed potent cell growth inhibitory activity with IC values below 20 μM. Two compounds ( TC-5 and TC-14) exhibited the most pronounced antiproliferative activity equivalent to or higher than that of positive control. The structure - activity relationship of these anticancer agents has been reviewed. The results indicate that incorporation of halogen into the benzene ring is beneficial for anticancer activity. [ABSTRACT FROM AUTHOR]

In the original version of this article the presentation of Figs 1, 2, 3 was incorrect. [ABSTRACT FROM AUTHOR]

Purpose: The optimal therapy involving linezolid or vancomycin for suspected methicillin-resistant Staphylococcus aureus (MRSA) nosocomial pneumonia (NP) remains controversial. This study compared the efficacy and safety of linezolid and vancomycin therapies in patients with NP. Methods: A systematic review of randomized controlled trials with meta-analyses performed by searching PubMed, EMBASE, MEDLINE, and the Cochrane Central Register of Controlled Trials. We screened for relevant randomized controlled studies in which patients with NP were enrolled and linezolid and vancomycin therapies were compared. Results: Nine trials involving 2618 pneumonia patients were reviewed. Linezolid was not found to be superior to vancomycin for clinical cure when categories of pathogen were not considered and in a subgroup of NP patients with MRSA infection [relative risk (RR) = 1.16, 95 % confidence interval (CI) = 0.95-1.43, P = 0.15]. Compared with vancomycin, linezolid has no difference in the overall microbiological eradication rate (RR = 1.12, 95 % CI = 0.96-1.30, P = 0.15) and specific MRSA eradication rate (RR = 1.16, 95 % CI = 0.93-1.45, P = 0.19) in NP patients. In addition, nephrotoxicity was more frequent with vancomycin (RR = 0.50, 95 % CI = 0.31-0.81, P = 0.005), but no differences between the treatments were found for all-cause mortality, thrombocytopenia, gastrointestinal effects, and drug discontinuation due to adverse events. Conclusion: These results suggest that linezolid is not superior to vancomycin with respect to both clinical and microbiological cure rates in patients with MRSA NP. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulation and atomic force microscopy are used to study the nature of friction between nanoscale tips and graphite step edges. Both techniques show that the width of the lateral force peak as the probe moves up a step is directly correlated with the size and shape of the tip. The origin of that relationship is explored and the similarities and differences between the measurements and simulations are discussed. The observations suggest that the relationship between lateral force peak width and tip geometry can be used as a real-time monitor for tip wear during atomic scale friction measurements. [ABSTRACT FROM AUTHOR]

The present work was done to investigate the possible effects of 3,4-oxo-isopropylidene-shikimic acid (ISA) on acetic acid (AA)-induced colitis in rats. Colitis was induced by intracolonic injection of 6 % AA. Several parameters, including macroscopic score and biochemical parameters, were determined to assess the degree of protection. Biochemical parameters such as myeloperoxidase (MPO) activity, malondialdehyde (MDA) and nitric oxide (NO) levels, and superoxide dismutase (SOD) and inducible NO synthase (NOS) activities were measured following standard assay procedures. The study showed that treatment of rats for 6 days with ISA (100 and 200 mg/kg) was able to give complete protection against AA-induced colitis. Moreover, biochemical changes were reversed and brought toward control. These results suggest a beneficial effect of ISA against experimental colitis and the possible mechanism of the protective effects may be partly due to an antioxidant action. [ABSTRACT FROM AUTHOR]

In this methods article, we describe application of Prandtl-Tomlinson models and their extensions to interpret dry atomic-scale friction. The goal is to provide a practical overview of how to use these models to study frictional phenomena. We begin with the fundamental equations and build on them step-by-step-from the simple quasistatic one-spring, one-mass model for predicting transitions between friction regimes to the two-dimensional and multi-atom models for describing the effect of contact area. The intention is to bridge the gap between theoretical analysis, numerical implementation, and predicted physical phenomena. In the process, we provide an introductory manual with example computer programs for newcomers to the field, and an illustration of the significant potential for this approach to yield new fundamental understanding of atomic-scale friction. [ABSTRACT FROM AUTHOR]

Friction between a nanoscale tip and a reconstructed Au(111) surface is investigated both by atomic force microscopy (AFM) and molecular statics calculations. Lateral force AFM images exhibit atomic lattice stick-slip behavior with a superstructure corresponding to the herringbone reconstruction pattern. However, the superstructure contrast is not primarily due to variations in the local frictional dissipation (which corresponds to the local width of the friction loop). Rather, the contrast occurs primarily because the local centerline position of the friction loop is periodically shifted from its usual value of zero. Qualitatively, similar behavior is reproduced in atomistic simulations of an AFM tip sliding on the reconstructed Au(111) substrate. In both simulations and experiments, this centerline modulation effect is not observed on unreconstructed surfaces. Similarly, using a topographically flat surface as a hypothetical control system, the simulations show that the centerline modulation is not caused by variations in the reconstructed surface's topography. Rather, we attribute it to the long-range variation of the local average value of the tip-sample interaction potential that arises from the surface reconstruction. In other words, surface atoms located at unfavorable sites, i.e., in the transition between face-centered-cubic (FCC) and hexagonal-close-packed (HCP) regions, have a higher surface free energy. This leads to a varying conservative force which locally shifts the centerline position of the friction force. This demonstrates that stick-slip behavior in AFM can serve as a rather sensitive probe of the local energetics of surface atoms, with an attainable lateral spatial resolution of a few nanometers. [ABSTRACT FROM AUTHOR]

We introduce a model AFM tip/substrate system that includes full atomistic detail as well as system compliance to study the transitions between three regimes of atomic friction: smooth sliding, stick-single slip, and stick-multiple slip. We characterize these atomic friction regimes in terms of static and dynamic effects, and investigate how the slip modes affect the mean friction. Molecular statics calculations show that reduced-order model predictions of possible transitions between slip regimes are generally adequate for a fully atomistic system, even for complex reaction coordinates. However, molecular dynamics simulations demonstrate that, while static features of the system govern possible slip regimes, dynamic effects ultimately determine actual transitions between slip regimes. [ABSTRACT FROM AUTHOR]

A recent note by Lu et al. presented a theoretical study of atomic friction using a two-spring Tomlinson model. In this comment, we argue that the conclusion of the note can be understood in a simple manner, and that the discussion of the criterion for the onset of stick-slip is unnecessarily complicated and potentially misleading. [ABSTRACT FROM AUTHOR]