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Feature selection is a fundamental pre‐processing step in machine learning that aims to reduce the dimensionality of a dataset by selecting the most effective features from the original features. This process is regarded as a combinatorial optimization problem, and the grey wolf optimizer (GWO), a novel meta‐heuristic algorithm, has gained popularity in feature selection due to its fast convergence speed and easy implementation. In this paper, an improved binary GWO algorithm incorporating a novel Population Adaptation strategy called PA‐BGWO is proposed. The PA‐BGWO takes into account the characteristics of the feature selection problem and designs three strategies. The proposed strategy includes an adaptive individual update procedure to enhance the exploitation ability and accelerate convergence speed, a head wolf fine‐tuned mechanism to exert the impact on each independent feature of the objective function, and a filter‐based method ReliefF for calculating feature weights with dynamically adjusted mutation probabilities based on the ranking features to effectively escape from local optima. Experimental comparisons with several state‐of‐the‐art feature selection methods on 15 classification problems demonstrate that the proposed approach can select a small feature subset with higher classification accuracy in most cases. [ABSTRACT FROM AUTHOR]

The morbidity and mortality of cardiovascular diseases (CVDs) have been increasing year by year all over the world and expanding greatly to the younger population, which becomes the leading causes of death globally that threatens human life safety. Prediction of the occurrence of diseases by using risk related adverse events is crucial for screening and early detection of CVDs. Thus, the discovery of new biomarkers that related to risks of CVDs are of urgent in the field. Retinol-binding protein 4 (RBP4) is a 21-kDa adipokine, mainly secreted by adipocytes. Besides its well-established function in the induction of insulin resistance, it has also been found in recent years to be closely associated with CVDs and other risk factors, such as hypertension, coronary heart disease, heart failure, obesity, and hyperlipidemia. In this review, we mainly focus on the progress of research that establishes the correlation between RBP4 and CVDs and the corresponding major risk factors in recent years. [ABSTRACT FROM AUTHOR]

Electrospun polymer/metal composite nanofibers have received much attention in the field of bone tissue engineering and regenerative medicine (BTERM) owing to their extracellular matrix- (ECM-) like structure, sufficient mechanical strength, favorable biological properties, and bone induction. In particular, electrospun nanofibers containing strontium (Sr) can significantly promote bone repair and regeneration by mediating osteolysis and osteogenesis, which offers a promising bioactive material for BTERM. In this review, we summarized the effects of electrospun nanofibers containing Sr on stem cells, osteoblasts, and osteoclasts in BTERM. Also, current challenges and future perspectives for electrospun nanofibers containing Sr in BTERM are briefly outlined. It is hoped that the systematic overview will inspire the readers to further study Sr-containing nanofibers for BTERM and accelerate their translation from the bench to the clinic. [ABSTRACT FROM AUTHOR]

Electrospun polymer/metal composite nanofibers have received much attention in the field of bone tissue engineering and regenerative medicine (BTERM) owing to their extracellular matrix- (ECM-) like structure, sufficient mechanical strength, favorable biological properties, and bone induction. In particular, electrospun nanofibers containing strontium (Sr) can significantly promote bone repair and regeneration by mediating osteolysis and osteogenesis, which offers a promising bioactive material for BTERM. In this review, we summarized the effects of electrospun nanofibers containing Sr on stem cells, osteoblasts, and osteoclasts in BTERM. Also, current challenges and future perspectives for electrospun nanofibers containing Sr in BTERM are briefly outlined. It is hoped that the systematic overview will inspire the readers to further study Sr-containing nanofibers for BTERM and accelerate their translation from the bench to the clinic. [ABSTRACT FROM AUTHOR]

Chitosan and its derivatives have been increasingly used for bacteriostasis. To date, the effect of chitosan and N-(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (HTCC) on Enterococcus faecalis (E. faecalis) associated with endodontic infection has remained to be determined. Chitosan and HTCC were serially diluted with double-distilled water (DDW) or PBS at concentrations of 20-2,500 µg/ml. Various strains of E. faecalis (American Type Tissue Collection no. 29212, as well as isolated strains P25RC and P52Sa) in plankton were adjusted to an optical density at 600 nm of 0.10 and treated with chitosan or HTCC. A colony-forming unit assay was used to determine the concentration of residual bacteria after treatment. Furthermore, E. faecalis biofilms were cultured on coverslips and treated with chitosan or HTCC. The coverslips were rinsed, stained using Live/dead® BacLight™ bacterial viability kit and observed under an inverted fluorescence microscope. In addition, biofilms on dentine blocks were prepared and observed under a scanning electron microscope. MC3T3-E1 pre-osteoblasts were seeded on 96-well plates and treated with chitosan or HTCC at various concentrations. The cytotoxicity of chitosan and HTCC on MC3T3-E1 pre-osteoblasts was detected using a Cell Counting Kit-8 assay after 24, 48 and 72 h of treatment. The results revealed that the final minimum bactericidal concentrations (MBC) of chitosan and HTCC dissolved in DDW were 70 and 140 µg/ml, respectively. Chitosan and HTCC in DDW exerted a significantly greater antibacterial effect as compared with that in PBS (P<0.05). At the MBC, chitosan and HTCC in DDW, but particularly chitosan, had a significant antibacterial effect on E. faecalis biofilm. Chitosan exhibited no cytotoxicity to MC3T3-E1 pre-osteoblasts at a concentration of <625 µg/ml, while HTCC inhibited the proliferation of the cells in the concentration range of 39-10,000 µg/ml. In conclusion, chitosan and HTCC exhibited prominent antibacterial properties on E. faecalis in the planktonic state and as a biofilm via charge interaction, indicating their potential for application in root canal disinfection and fillings. [ABSTRACT FROM AUTHOR]