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The potential of superhydrophobic surfaces has gained vast attention in medical settings due to their self‐cleaning effect (including bacterial colonization reduction), minimized cell‐to‐surface interaction, and anti‐biofouling effect. These valuable features allow the vanquishment of some limitations accompanying the blood‐contacting medical devices that are widely used in clinical practice. The extracorporeal circulation used to perform hemodialysis, for instance, as well as the blood collection sets, these essential blood‐contacting medical devices are frequently associated with bacterial infection and hemolysis. Within this study, superhydrophobic surface was substantiated to enhance the biocompatibility. Herein, the graphene (Gr) and titanium dioxide (TiO2) nanoparticles were dip‐coated on poly(lactic acid) (PLA) film to produce a superhydrophobic surface. The uniform distribution of the Gr/TiO2 nanoparticles of the coating enhanced the surface roughness and therefore promoted superhydrophobic properties. Co‐occurrence of the Cassie‐Baxter regime and Wenzel regime was suggested to induce the low surface wettability. The superhydrophobic Gr/TiO2 demonstrated significant inhibition of biofilm formation and antibacterial activity against Staphylococcus aureus, Klebsiella pneumoniae and Pseudomonas aeruginosa. Besides, the in vitro blood compatibility assay showed a hemolysis rate lower than 2%, which was categorized as nonhemolytic. The exposure of human heart cells and kidney cells to the Gr/TiO2‐coated PLA film did not significantly affect the cell viability. The findings herein showed promising results for the superhydrophobic Gr/TiO2‐coated PLA film to act as a potential biomaterial for single‐use blood‐contacting medical devices. This study also provided insight for future medical applications that require superhydrophobic coatings. [ABSTRACT FROM AUTHOR]

Background: The commercial cultured milk drinks contain either single or mixed probiotic species and supply in different serving sizes. It is known that different combinations of probiotics might provide the various products' quality in terms of nutritional value during their manufacturing process. However, a lack of information about probiotic viability and physicochemical properties of the opened fermented products for continuous fermentation leads to the driving force in conducting this study. Therefore, four locally available cultured milk drinks (branded Y, F, N and V) with 20 bottles each were aseptically transferred into their respective sterile containers and stored at 4 °C, 25 °C and − 20 °C for 1–13 days. Then, the viable cells were quantified using the drop plate method on de Man, Rogosa and Sharpe (MRS) agar. The pH change was investigated using the calibrated pH meter, and the Enzytec D-/L-Lactic acid kit determined the content of D-lactic acid via spectrophotometer. Eventually, the data were analysed using the statistical tool. Results: The viability of probiotics in brands Y and V was significantly increased even when stored at − 20 °C and 4 °C with at least 1 log CFU/mL increment. The proliferation of probiotics was moderately influenced by the pH of the opened cultured milk. High content of D-lactate was found in Y- and F-branded products after 13 days of storage. The Y-branded cultured milk drink had the highest content of D-lactate with 0.52 g/L and 0.40 g/L when stored for 13 days at room temperature and 4 °C, respectively. Conclusions: This study sheds light on the necessity to elucidate the properties of opened probiotic beverages over time, especially when bottled in large quantities. This allows some improvement steps. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus expresses diverse proteins at different stages of growth. The immunodominant staphylococcal antigen A (IsaA) is one of the proteins that is constitutively produced by S. aureus during colonisation and infection. SACOL2584 (or isaA) is the gene that encodes this protein. It has been suggested that IsaA can hydrolyse cell walls, and there is still need to study isaA gene disruption to analyse its impact on staphylococcal phenotypes and on alteration to its transcription and protein profiles. In the present study, the growth curve in RPMI medium (which mimics human plasma), autolytic activity, cell wall morphology, fibronectin and fibrinogen adhesion and biofilm formation of S. aureus SH1000 (wildtype) was compared to that of S. aureus MS001 (isaA mutant). RNA sequencing and liquid chromatography–tandem mass spectrometry were carried out on samples of both S. aureus strains taken during the exponential growth phase, followed by bioinformatics analysis. Disruption of isaA had no obvious effect on the growth curve and autolysis ability or thickness of cell walls, but this study revealed significant strength of fibronectin adherence in S. aureus MS001. In particular, the isaA mutant formed less biofilm than S. aureus SH1000. In addition, proteomics and transcriptomics showed that the adhesin/biofilm-related genes and hemolysin genes, such as sasF, sarX and hlgC, were consistently downregulated with isaA gene disruption. The majority of the upregulated genes or proteins in S. aureus MS001 were pur genes. Taken together, this study provides insight into how isaA disruption changes the expression of other genes and has implications regarding biofilm formation and biological processes. [ABSTRACT FROM AUTHOR]

Concerns on increasing trends of multidrug resistance (MDR) around the world have triggered the need to investigate and develop new therapeutic strategies and potent antibacterial drugs. Polymyxins, a class of polycationic antimicrobial peptides, have been regarded as the last-line therapy against Gram-negative bacteria due to limited new antibiotics and phenylalanine-arginine β-naphthylamide (PAβN), a peptidomimetic compound has been characterised as an efflux pump inhibitor (EPI) that have been investigated to overcome efflux-mediated multidrug resistance. In this work, the antibacterial activity of two Schiff base ligands derived from the condensation of S-benzyl dithiocarbazate with 4-carboxybenzaldehye (SB4CB) and 4-formyl-3-hydroxybenzoic acid (SBFH) their copper(II) complexes (Cu(SB4CB)2 and Cu(SBFH)2) were tested individually, and the most promising compound was tested in combination with polymyxin B (POLY) and PAβN against different bacteria, such as antibiotic-susceptible strains: Acinetobacter baumannii ATCC 19606, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, and Staphylococcus aureus ATCC 35923; multidrug-resistant strains: A. baumannii ATCC BAA-1797, E. coli BAA-196, P. aeruginosa ATCC BAA-2108 and S. aureus ATCC 43300. Initial minimum inhibition concentration (MIC) results showed the Cu(II) complexes Cu(SB4CB)2 and Cu(SBFH)2, demonstrated obvious antibacterial activity as compared to the ligand alone. Fractional inhibitory concentration (FIC) index showed improved MIC values with additivity and synergistic effect for Cu(SBFH)2 in combination with POLY and PAβN. From the in silico molecular docking investigation, Cu(SBFH)2 was shown to engage in hydrophobic interactions via its phenyl rings with surrounding hydrophobic residues in the binding pocket of S. aureus NorA, E. coli AcrB, P. aeruginosa MexB and A. baumannii AdeB efflux pumps. The phenyl rings of the ligand could also form π-π stacking with adjacent residues in the binding site of A. baumannii AdeB. Besides, hydrogen bonding and π-cation interactions were also observed via the carboxyl group, hydroxyl group and phenyl ring of SBFH moiety, respectively with nearby residues in the E. coli AcrB binding pocket. This study indicates that the combination strategy of Cu(SBFH)2 with POLY and PAβN enhances therapeutic potential and sheds light on the binding pockets inside bacteria efflux pumps and the binding interactions of ligand in the binding site. [ABSTRACT FROM AUTHOR]

Studies on environmental-friendly surfactants are essential to potentially replace those highly toxic and non-biodegradable commercially available surfactants. Two biocompatible polymeric anionic (AS1) and nonionic (NS1) surfactants were successfully synthesised from palm oil derivatives via polyesterification. The cytotoxicity of surfactants was measured by in vitro succinate dehydrogenase activity (MTT assay). Results revealed that both surfactants achieved cell viability above 80% against human keratinocytes (HaCaT), mouse fibroblasts (3T3), mouse hepatocytes (H2.35) and canine kidney cells (MDCK) in both dose- and time-dependent manners. Antimicrobial potential of both surfactants was evaluated using minimum bactericidal concentration (MBC) assay. Results indicated that AS1 had a significant antimicrobial activity against most of the tested Gram-positive bacteria. Meanwhile, only one of the Gram-negative bacteria (Acinetobacter baumannii) was successfully reduced by NS1. Both surfactants were subsequently compounded into natural rubber latex (NRL). From rheological study, AS1 exhibited better viscosity behaviour with longer linear viscoelastic region (LVR) towards high ammonia (HA) NRL, signifying its potential in providing stability in the latex environment. [ABSTRACT FROM AUTHOR]

A series of novel phenothiazine based [1,2,4]triazolo[4, 3‐a]pyridine scaffolds were designed and synthesized in good yields by the oxidative cyclisation of phenothiazine pyridylhydrazones. Biological responses of all compounds toward a panel of human breast cancer cells (MDA‐MB‐231, MDA‐MB‐468, MCF7, SKBR3 and T47D) and human non‐tumorigenic epithelial breast cells (MCF10 A) were evaluated. Structure‐activity relationship revealed that compound with pendant phenyl ring on phenothiazine exhibited significant cytotoxic activity and apoptotic induction effects against breast cancer cell line with IC50 value 10.2 to 17.6 μM. Notably, the cytotoxic effect was 3.5 fold higher on cancer than non‐cancer cells, indicating potential control of breast cancer with lower side effects. Molecular docking studies confirmed the presence of hydrophobic contacts between appended phenyl ring, triazolopyridine and phenothiazine moieties with adjacent residues within the binding pocket of tubulin. One of the nitrogen in the triazolo ring also showed hydrogen bonding with tubulin. These tubulin interactions were also found with the taxane ring of paclitaxel. Cell cycle analysis confirmed the G2/M arrest induced by this compound on human breast cancer cells. Therefore, the potential anti‐cancer, pro‐apoptotic, and cell cycle arrest warrant further development of this molecule as a new class of anticancer agent. [ABSTRACT FROM AUTHOR]

Objectives: Antiretroviral agents (ARVs) have been the most promising line of therapy in the management of human immunodeficiency virus (HIV) infections. Some of these ARVs are used in the pre‐exposure prophylaxis (PrEP) to suppress the transmission of HIV. Prophylaxis is primarily used in uninfected people, before exposure, to effectively prevent HIV infection. Several studies have shown that ART PrEP prevents HIV acquisition from sexual, blood and mother‐to‐child transmissions. However, there are also several challenges and limitations to PrEP. This review focuses on the current antiretroviral therapies used in PrEP. Key findings: Among ARVs, the most common drugs employed from the class of entry inhibitors are maraviroc (MVC), which is a CCR5 receptor antagonist. Other entry inhibitors like emtricitabine (FTC) and tenofovir (TFV) are also used. Rilpivirine (RPV) and dapivirine (DPV) are the most common drugs employed from the Non‐nucleoside reverse transcriptase inhibitor (NNRTIs) class, whereas, tenofovir disoproxil fumarate (TDF) is primarily used in the Nucleoside Reverse Transcriptase Inhibitor (NRTIs) class. Cabotegravir (CAB) is an analog of dolutegravir, and it is an integrase inhibitor. Some of these drugs are also used in combination with other drugs from the same class. Summary: Some of the most common pre‐exposure prophylactic strategies employed currently are the use of inhibitors, namely entry inhibitors, non‐nucleoside reverse transcriptase inhibitors, nucleoside reverse transcriptase inhibitors, integrase and protease inhibitors. In addition, we have also discussed on the adverse effects caused by ART in PrEP, pharmacoeconomics factors and the use of antiretroviral prophylaxis in serodiscordant couples. [ABSTRACT FROM AUTHOR]

ABSTRACT A series of vegetable oil microemulsions are formulated and incorporated into NR latex to study the potent antimicrobial activity of vegetable oil-plasticized NR latex film against the adherent bacteria on the treated film. The particle size of latex incorporated with 2.50 phr of oil has attained up to 424 nm after incubated at 35 ± 2 °C for 24 h. The tensile stress of all NR latex films are relatively low, ranged 0.289 to 0.511 MPa. All emulsions are found compatible with NR and the low contact angles (<90°) corresponded to no oil blooming onto the surfaces of NR latex films. The crosslink densities are in good correlation with tensile strengths. The potent antimicrobial properties of the NR latex films are investigated from the viability assessment of the adherent tested Escherichia coli ATCC 25922 ( E. coli ATCC 25922) and Staphylococcus aureus ATCC 25923 ( S. aureus ATCC 25923). Results shows that NR latex film incorporated with palm kernel oil/soybean oil blend, NR-E(P/S = 7/3), has significantly killed the adherent S. aureus with 92.5% reduction but showed no significant log reduction in E. coli. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44788. [ABSTRACT FROM AUTHOR]

Medical devices are indispensable in the healthcare setting, ranging from diagnostic tools to therapeutic instruments, and even supporting equipment. However, these medical devices may be associated with life-threatening complications when exposed to blood. To date, medical device-related infections have been a major drawback causing high mortality. Device-induced hemolysis, albeit often neglected, results in negative impacts, including thrombotic events. Various strategies have been approached to overcome these issues, but the outcomes are yet to be considered as successful. Recently, superhydrophobic materials or coatings have been brought to attention in various fields. Superhydrophobic surfaces are proposed to be ideal blood-compatible biomaterials attributed to their beneficial characteristics. Reports have substantiated the blood repellence of a superhydrophobic surface, which helps to prevent damage on blood cells upon cell–surface interaction, thereby alleviating subsequent complications. The anti-biofouling effect of superhydrophobic surfaces is also desired in medical devices as it resists the adhesion of organic substances, such as blood cells and microorganisms. In this review, we will focus on the discussion about the potential contribution of superhydrophobic surfaces on enhancing the hemocompatibility of blood-contacting medical devices. [ABSTRACT FROM AUTHOR]

In the 21st century, enteric fever is still causing a significant number of mortalities, especially in high-risk regions of the world. Genetic studies involving the genome and transcriptome have revealed a broad set of candidate genetic polymorphisms associated with susceptibility to and the severity of enteric fever. This review attempted to explain and discuss the past and the most recent findings on human genetic variants affecting the progression of Salmonella typhoidal species infection, particularly toll-like receptor (TLR) 4, TLR5, interleukin (IL-) 4, natural resistance-associated macrophage protein 1 (NRAMP1), VAC14, PARK2/PACRG, cystic fibrosis transmembrane conductance regulator (CFTR), major-histocompatibility-complex (MHC) class II and class III. These polymorphisms on disease susceptibility or progression in patients could be related to multiple mechanisms in eliminating both intracellular and extracellular Salmonella typhoidal species. Here, we also highlighted the limitations in the studies reported, which led to inconclusive results in association studies. Nevertheless, the knowledge obtained through this review may shed some light on the development of risk prediction tools, novel therapies as well as strategies towards developing a personalised typhoid vaccine. [ABSTRACT FROM AUTHOR]