Effective physiological bone integration and absence of bacterial infection are essential for a successful orthopaedic or dental implant. This work elucidated the antibacterial efficacy and cytocompatibility of electroplated Cu(II) and Zn(II) co-substituted hydroxyapatite (HAP) (i.e., ZnCuHAP) coating on commercially pure titanium (Ti-cp). To improve the antibacterial property of pure HAP, Cu 2+ was substituted into its structure.Simultaneously, Zn 2+ is co-substituted as secondary material into CuHAP to offset the potential cytotoxicity of Cu, because elevated Cu concentration is toxic. The as-deposited coatings were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray spectroscopy. Co-doping of Zn 2+ and Cu 2+ into HAP reduced the porosity, resulting in a denser coating. The Zn 2+ and Cu 2+ ions were homogenously co-deposited into HAP films. Potentiodynamic polarisation test revealed 2 that the ZnCuHAP covered coating provided good barrier characteristics and achieved superior corrosion protection for Ti substrates. The as-prepared ZnCuHAP coating was found to be highly effective against Escherichia coli in vitro. In vitro biocompatibility tests and MTT were employed to assess the cytotoxicity of ZnCuHAP coating with osteoblast-like MC3T3-E1 cells. No adverse effect or cytotoxicity on osteoblasts by Zn/Cu addition was observed, revealing that the co-substitution of Zn in CuHAP efficiently offsets the adverse effects of Cu and improves the performance compared with that of pure HAP. 15 comparison with the HAP coating and the control. Antimicrobial results revealed that Cu ions released from ZnCuHAP present a strong bactericidal effect against these organisms (antimicrobial ratio > 95%). This enhancement may be due to the high release of copper in ZnCuHAP in the PBS medium after 24 h incubation (based on the ICP-AES analysis).The antibacterial tests results revealed that pure HAP coating has no antibacterial property.The pure HAP plate showed more colonies than the control sample (Fig. 6). This finding showed that proteins, amino acids, and other organic matter are readily adsorbed on the HAP surface, which could favour adsorption and replication of bacteria on the coating, usually causing implant-related infections [37]. Therefore, endowing antimicrobial properties to HAP is necessary. Several recent studies have introduced antimicrobial activity of materials that involve Cu(II) ions. Du et al. [38] have suggested that chitosan nanoparticles loaded with Cu(II) ions interact with bacterial cell membranes of E. coli, causing structural changes and, eventually, cell death. Nan et al. [39] also suggested that structure of the outer cell membrane responsible for cell permeability is significantly altered for E. coli after contact with antimicrobial stainless steel with Cu(II) ions. This finding indicates that cell walls were badly undermined, and numerous cellular contents are released. Notably, Zn ions released fromZnCuHAP may also exhi...

This work elucidated the antibacterial efficacy, corrosion resistance, and cytotoxicity of electroplated copper-substituted hydroxyapatite (CuHAP) coating on titanium (Ti). The fabricated CuHAP coatings were characterized by scanning electron microscopy, energydispersive X-ray analysis spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction studies. The CuHAP coating had needle-like apatite crystals, the doping of Cu 2? into HAP reduced porosity, and the coating became denser. The CuHAP crystals were carbonated with a few of Cu 2? incorporation (about 0.80 wt%). The Cu 2? ions were homogenously deposited into HAP films. Potentiodynamic polarisation test revealed that the CuHAP coating provided good barrier characteristics and achieved superior corrosion protection for Ti substrates. The in vitro antibacterial activity of asprepared CuHAP coating was evaluated against Escherichia coli and was found to be effectively high against bacterial colonization. Bioactivity test conducted by soaking the coatings in simulated body fluid demonstrated that CuHAP coating can quickly induce bone-like apatite nucleation and growth. In vitro biocompatibility tests, MTT, were employed to assess the cytotoxicity of Cu-HAP coating with osteoblast-like MC3T3-E1 cells. The obtained HAP coating doped with a low content of Cu 2? exhibited good cytocompatibility and had no toxicity toward MC3T3-E1.

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In this research, the durability of skid resistance during the ice melting process with temperature increasing from −5 °C to 10 °C was characterized by means of a British Pendulum Skid Tester. Four types of pavement surfaces were prepared and tested. The difference between two antiskid layers prepared with bitumen emulsion was the aggregate. The detailed angularity and form 2D index of fine aggregates used for antiskid surfaces, characterized by means of the Aggregate Image Measure System (AIMS) with micro image analysis methods, were then correlated with British Pendulum Number (BPN) values. Results indicate that skid resistance has the lowest value during the ice-melting process. The investigated antiskid layers can increase the surface friction during icy seasons. In icy conditions, the skid resistance behavior first worsens until reaches the lowest value, and then increases gradually with increasing temperature. Results from ice-melting conditions on four investigated pavement surfaces give the same temperature range where there will be lowest skid resistance. That temperature range is from 3 °C to 5 °C. A thicker ice layer will result in a lower skid resistance property and smaller “lowest BPN”.

Objective We aimed to clarify the cognitive function of patients with chronic obstructive pulmonary disease (COPD) and different nutritional status. Methods Among 95 patients with COPD in this retrospective study, we administered the Nutritional Risk Screening 2002 (NRS 2002) and Mini-Mental State Examination (MMSE). We recorded patients’ clinical characteristics, comorbidities, and laboratory measurements. According to NRS 2002 scores, patients were divided into two groups: no nutritional risk with NRS 2002 < 3 ( n = 54) and nutritional risk, with NRS 2002 ≥ 3 ( n = 41). Results We found a negative correlation between NRS 2002 and MMSE scores in participants with COPD ( r = −0.313). Patients with nutritional risk were more likely to be cognitively impaired than those with no nutritional risk. Multivariate logistic regression analysis indicated that malnutrition was an independent risk factor for cognitive impairment, after adjusting for confounders (odds ratio [OR] = 4.120, 95% confidence interval [CI]: 1.072–15.837). We found a similar association between NRS 2002 and MMSE scores at 90-day follow-up using a Pearson’s correlation test ( r = −0.493) and logistic regression analysis (OR = 7.333, 95% CI: 1.114–48.264). Conclusions Patients with COPD at nutritional risk are more likely to have cognitive impairment.

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