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Abstract The objectives of this study were: 1) to determine biofilm formation abilities of 11 emetic toxin producing Bacillus cereus strains along with two reference strains ATCC 14579 and KCTC 13153 on stainless steel and plastic coupons; 2) to examine the correlation between biofilm formation ability and genotypic and phenotypic characteristics of four selected strains. Crystal violet assay results indicated that the biofilm formation behavior was highly variable depending on strain and surface. Cell enumeration and scanning electron microscopy (SEM) analysis showed complex cell clusters with extracellular polymeric substances (EPS) for high biofilm forming strains and single layer of cell clusters with few EPS for low biofilm forming strains. Phenotypic characteristics of planktonically grown cells such as hydrophobicity were positively correlated with biofilm formation behavior. However, antibiotic susceptibility of B. cereus strains was not correlated with biofilm formation, although resistance to benzalkonium chloride showed a clear correlation with biofilm formation ability. Expression levels of two genes spo0A and abrB involved in the regulation of cell differentiation and mobility of B. cereus were positively correlated with biofilm formation. Results of this study indicate that multiple factors are involved in biofilm formation by emetic toxin producing B. cereus. Highlights • B. cereus biofilm formation largely depends on strain and surfaces. • Expression of spo0A and abrB genes involves in motility and biofilm formation. • Antibiotic susceptibility of planktonic cells does not relate to biofilm formation. • Resistance to BAC shows clear correlation with biofilm formation level. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Conjugation of tauroursodeoxycholic acid (TUDCA) to Lys-27 of exendin-4 (Ex4). • TUDCA-Lys27-Ex4 (TUM1-Ex4) showed strong activity as a GLP-1 receptor agonist. • TUM1-Ex4 reduced the expression of GRP78 and levels of phosphorylated eIF2α. Abstract Endoplasmic reticulum stress has been considered a major cause of pancreatic β-cell dysfunction and apoptosis leading to diabetes. Glucagon-like peptide-1 receptor activation and chemical chaperones have been known to reduce endoplasmic reticulum stress and improve β-cell function and survival. The purpose of this study was to prepare and evaluate the chemical chaperone tauroursodeoxycholic acid-conjugated exendin-4 as a protective agent for pancreatic β-cells. Mono-tauroursodeoxycholic acid-Lys27-exendin-4 conjugate (TUM1-Ex4) showed better receptor binding affinity than other conjugates with strong in vitro insulinotropic activity in rat pancreatic β-cells and in vivo hypoglycemic activity in type 2 diabetic db/db mice. In INS-1 cells under endoplasmic reticulum stress induced by thapsigargin, TUM1-Ex4 promoted cell survival in a dose-dependent manner. In western blot analysis, TUM1-Ex4 reduced the expression of the endoplasmic reticulum stress marker GRP78 and phosphorylation of the translation initiation factor eIF2α. These results reveal that TUM1-Ex4 accelerates translational recovery and contributes to β-cell protection and survival. The present study indicates that the chemical chaperone-coupled glucagon-like peptide-1 receptor agonist is a feasible therapeutic strategy to enhance β-cell function and survival. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to evaluate the impact of CSC on insensitivity to radiotherapy in HNSCC.Methods: A radioresistant cell line, FaDu-R, was established using fractionated ionizing radiation. Cells with high and low CD44/ALDH activity were isolated.Results: FaDu-R cells demonstrated significantly increased cell viability after radiation exposure compared with parental cells. CD44high/ALDHhigh FaDu-R cells demonstrated significantly faster wound closure (p<0.05) and more efficient invasion (p<0.05) compared to the CD44high/ALDHhigh FaDu cells or the CD44low/ALDHlow FaDu-R cells. There was a significant difference in tumor volume between the CD44high/ALDHhigh FaDu-R cells and the CD44high/ALDHhigh FaDu cells (p<0.05) as well as the CD44low/ALDHlow FaDu-R cells (p<0.05).Conclusion: Cancer stem cells (CSC) were associated with invasion and tumorigenesis in a radioresistant head and neck squamous cell carcinoma (HNSCC) cell line. This concept might help to improve the understanding of these mechanisms and to develop drugs that can overcome radioresistance during radiotherapy. [ABSTRACT FROM AUTHOR]

Purpose To compare bioabsorbable plates with metal miniplate systems for use in endoscope-assisted open reduction and internal fixation (EAORIF) of mandibular subcondylar fractures. Materials and methods This retrospective cohort study included patients with mandibular subcondylar fractures treated with EAORIF using bioabsorbable unsintered hydroxyapatite/poly l -lactide composite plates or titanium miniplate systems. The outcome variables included preoperative fracture conditions, postoperative stability during fracture healing, and complications during the follow-up period. Other variables included clinical characteristics (age, sex, fracture site, and total follow-up duration) and intra- and postoperative data (surgical duration, duration of intermaxillary fixation/elastic band guidance). Variables were evaluated using descriptive statistics and compared between groups using the Mann–Whitney test and the chi-square test or Fisher's exact test, as appropriate. Results In total, 28 patients were analyzed, including 13 who underwent EAORIF using bioabsorbable plates and 15 who underwent EAORIF using titanium miniplates. With the exception of second surgery for plate removal, none of the assessed variables showed significant differences between the two groups (p < 0.05). Conclusions Our results suggest that EAORIF using biodegradable plates is a stable and reliable method for the management of mandibular subcondylar fractures and eliminates the need for secondary surgery for plate removal. [ABSTRACT FROM AUTHOR]

Polytetrafluoroethylene (PTFE) membrane was dip-coated with a hexane-based solution containing polydimethylsiloxane (PDMS)-coated SiO 2 nanoparticles, fluidic PDMS, and curing agent as a binder for imparting superhydrophobicity to the PTFE, with water contact angle above 160°. The dip-coated PTFE membrane showed very high gas (dimethyl methylphosphonate (DMMP) and water vapours) permeability under humidity conditions of 0–32% of relative humidity and DMMP concentrations of about 1–2 ppms with a total gas flow of 15 sccm, yet completely repelled liquid water. We used the dip-coated PTFE membrane as a protective layer to prevent contact between the gas sorbent material (namely activated carbon fibre; ACF) and the liquid water. We studied the sorption behaviour of DMMP in an assembly of ACF and a protective layer under dry conditions and two different humidity conditions (16 and 32% RH). DMMP uptake was enhanced as relative humidity increased; however, in subsequent ex-situ FT-IR analysis, the intensity of the DMMP-related signal decreased with increasing humidity during the DMMP sorption experiments. Based on these results, we suggest that DMMP can mostly irreversibly chemisorb on ACF under dry conditions, but exhibits more dominantly reversible physisorption in the presence of water vapour. ACF can act as filter of DMMP under a wide range of humidity conditions, yet the DMMP uptake mechanism of ACF differs depending on the humidity of the environment. We demonstrate the potential application of our structure as a cartridge for respirator or protection garments. [ABSTRACT FROM AUTHOR]

Sanguiin H-6 is a dimer of casuarictin linked by a bond between the gallic acid residue and one of the hexahydroxydiphenic acid units. It is an effective compound extracted from Rubus coreanus . It has an anticancer effect against several human cancer cells; however, its effect on breast cancer cells has not been clearly demonstrated. Thus, we aimed to investigate the anticancer effect and mechanism of action of sanguiin H-6 against two human breast carcinoma cell lines (MCF-7 and MDA-MB-231). We found that sanguiin H-6 significantly reduced cell viability in a concentration-dependent manner. It also increased the rates at which MCF-7 and MDA-MB-231 cells underwent apoptosis. Furthermore, sanguiin H-6 induced the cleavage of caspase-8, caspase-3, and poly(ADP-ribose) polymerase, which resulted in apoptosis. However, cleavage of caspase-9 was only detectable in MCF-7 cells. In addition, sanguiin H-6 increased the ratio of Bax to Bcl-2 in both MCF-7 and MDA-MB-231 cells. These findings suggest that sanguiin H-6 is a potent therapeutic agent against breast cancer cells. In addition, it exerts its anticancer effect in an estrogen-receptor-independent manner. [ABSTRACT FROM AUTHOR]

A superhydrophobic and oleophobic film was fabricated on polytetrafluoroethylene (PTFE) using SiO 2 nanoparticles and 1H , 1H , 2H , 2H -perfluorooctyltrichlorosilane (FOTS). The surface of the bare PTFE sheet was first coated with SiO 2 nanoparticles by the dip-coating method, and FOTS was subsequently deposited on the SiO 2 -coated PTFE by either dip-coating or vapor deposition. Both of the FOTS-coated PTFE samples prepared using either dip-coating or vapor deposition initially showed high repellence towards water and hexadecane droplets. The FOTS-PTFE prepared by vapor deposition gradually absorbed hexadecane. By contrast, the dip-coated FOTS-PTFE displayed a durable non-wetting property, even after exposure to acidic/basic solutions and UV light irradiation. Gas permeability of the prepared superhydrophobic and oleophobic PTFE sheets towards CO 2 and dimethyl methylphosphonate (DMMP) vapor was also determined. We suggest that our superhydrophobic and oleophobic membrane could be used as the shielding layer of a gas sensor, to repel various liquids and only allow transmission of gases. [ABSTRACT FROM AUTHOR]

Objective Study results on the effects of coffee consumption on serum uric acid (UA) have been conflicting. The aim of this study is to analyze the literature regarding the effect of coffee consumption on serum UA. Methods We searched MEDLINE, EMBASE, the Cochrane library, and KoreaMed for all articles published before January 2015. Studies with quantitative data on coffee consumption and serum UA level were included. Coffee consumption and serum UA level were identified with/without the risk of gout. Results Nine studies published between 1999 and 2014 were included, containing a total of 175,310 subjects. Meta-analysis demonstrated that coffee has a significantly lowering effect on serum UA, where there are gender differences in the amount of coffee required to lower serum UA. Women (4–6 cups/day) need more coffee to lower serum UA than men (1–3 cups/day). Meta-analysis showed that coffee intake of 1 cup/day or more was significantly associated with reduction of the risk of gout, with a negative correlation with the amount of daily coffee intake for both genders. Conclusions This is the first systematic review on the effects of coffee consumption on serum UA. Based on our study, moderate coffee intake might be advocated for primary prevention of hyperuricemia and gout in both genders. [ABSTRACT FROM AUTHOR]

Study Objective: We explored the feasibility of a Clinical Decision Support System (CDSS) to guide evidence-based perioperative anticoagulation.Design: Prospective randomised clinical management simulation multicentre study.Setting: Five University and 11 general hospitals in Germany.Participants: We enrolled physicians (anaesthesiologist (n = 73), trauma surgeons (n = 2), unknown (n = 1)) with different professional experience.Interventions: A CDSS based on a multiple-choice test was developed and validated at the University Hospital of Frankfurt (phase-I). The CDSS comprised European guidelines for the management of anticoagulation in cardiology, cardio-thoracic, non-cardio-thoracic surgery and anaesthesiology. Phase-II compared the efficiency of physicians in identifying evidence-based approach of managing perioperative anticoagulation. In total 168 physicians were randomised to CDSS (PERI-KOAG) or CONTROL.Measurements: Overall mean score and association of processing time and professional experience were analysed. The multiple-choice test consists of 11 cases and two correct answers per question were required to gain 100% success rate (=22 points).Main Results: In total 76 physicians completed the questionnaire (n = 42 PERI-KOAG; n = 34 CONTROL; attrition rate 54%). Overall mean score (max. 100% = 22 points) was significantly higher in PERI-KOAG compared to CONTROL (82 ± 15% vs. 70 ± 10%; 18 ± 3 vs. 15 ± 2 points; P = 0.0003). A longer processing time is associated with significantly increased overall mean scores in PERI-KOAG (≥33 min. 89 ± 10% (20 ± 2 points) vs. <33 min. 73 ± 15% (16 ± 3 points), P = 0.0005) but not in CONTROL (≥33 min. 74 ± 13% (16 ± 3 points) vs. <33 min. 69 ± 9% (15 ± 2 points), P = 0.11). Within PERI-KOAG, there is a tendency towards higher results within the more experienced group (>5 years), but no significant difference to less (≤5 years) experienced colleagues (87 ± 10% (19 ± 2 points) vs. 78 ± 17% (17 ± 4 points), P = 0.08). However, an association between professional experience and success rate in CONTROL has not been shown (71 ± 8% vs. 70 ± 13%, 16 ± 2 vs. 15 ± 3 points; P = 0.66).Conclusions: CDSS significantly improved the identification of evidence-based treatment approaches. A precise usage of CDSS is mandatory to maximise efficiency. [ABSTRACT FROM AUTHOR]

TiO 2 nanoparticles were used as MALDI matrix for detecting dimethyl methylphosphate (DMMP) and its efficiency, in terms of DMMP signal intensity in the MALDI-MS analysis, was compared with that of polydimethylsiloxane (PDMS)-coated TiO 2 matrix. Intensity of the DMMP signal in the MALDI-MS analysis was significantly increased by using PDMS-coated TiO 2 matrix instead of bare ones. It was verified using FT-IR that the enhanced DMMP signal upon PDMS coating on TiO 2 matrix is a result of weaker interactions between DMMP molecule and the PDMS-covered surface than that of bare TiO 2 . A weaker DMMP-matrix interaction can facilitate desorption of DMMP from the matrix surface in the MALDI process, yielding a higher sensitivity to DMMP in the MALDI-MS. [ABSTRACT FROM AUTHOR]

Although collagen pentapeptide (Lys-Thr-Thr-Lys-Ser, KTTKS) has received a great deal of attention owing to its collagen biosynthesis-stimulating effects, its enzymatic instability in the skin is an obstacle to effective topical application. PEGylation is a useful approach for improving the chemical and biological stability of peptides. However, the polydispersity of poly(ethylene glycol) (PEG) produces conjugates with different molecular sizes, which may create difficulties in chemical characterization and purity control, and in variability of biological properties. To overcome these difficulties, monodisperse PEG was site-specifically conjugated to the N-terminal amine of KTTKS to produce a single molecular conjugate, enabling more complete chemical characterization and more exact product specifications. PEG–KTTKS conjugates prepared using monodisperse PEG with two different molecular weights, monodisperse PEG 220 and PEG 572 , were characterized by mass spectrometry. These monodisperse PEG–KTTKS conjugates showed no cytotoxicity (1–100 μM) and stimulated collagen biosynthesis in human skin fibroblasts. They also had high stability against proteolytic enzymes in rat skin. This study demonstrates the usefulness of monodisperse PEG for preparing chemically defined conjugates and suggests that monodisperse PEG-KTTKS would be a good candidate for use as a collagen biosynthesis-stimulating agent. [ABSTRACT FROM AUTHOR]

Abstract: We made attempts to improve photocatalytic activity of TiO2 nanoparticles under visible light exposure by combining additional treatments. N-doping of TiO2 by ammonia gas treatment increased absorbance of visible light. By coating thin film of polydimethylsiloxane, and subsequently vacuum-annealing, TiO2 surface became more hydrophilic, thereby enhancing photocatalytic activity of TiO2. These two treatments were combined for the first time in this work and photocatalytic activity under visible light irradiation exceeded sum of individual effects of N-doping and hydrophilic modification. [Copyright &y& Elsevier]

Highlights: [•] The catalytic activity of NiO/SiO2 catalysts for toluene combustion was measured. [•] NiO catalysts can be efficient for toluene combustion below as well as above 200°C. [•] High activity of NiO/SiO2 catalysts is related to large surface area of mesoporous SiO2 substrates. [ABSTRACT FROM AUTHOR]

Abstract: Photocatalytic decomposition of toluene was studied using commercially available TiO2 nanocatalysts (Degussa P25) under different ranges of relative humidity (RH). The toluene removal efficiency (sum of toluene adsorption, and partial and total oxidation) decreased with increasing RH, whereas the selectivity to CO2 in toluene oxidation enhanced. The enhancement in activity in terms of total oxidation at higher RH led to suppressing deactivation of TiO2 with time. On the basis of the humidity effect on photocatalytic reaction, deactivated TiO2 catalyst could recover their activity through the regeneration process consisting of exposure of the deactivated catalysts to the UV light under high RH conditions. The regenerated catalysts under high RH showed a higher total oxidation yield of toluene than that of the original catalysts due to the formation of more hydroxyl groups on TiO2 surface during the regeneration process. [Copyright &y& Elsevier]

Sepsis is a potentially fatal complication of infections and there are currently no effective therapeutic options for severe sepsis. In this study, we revealed the secretion mechanism of transforming growth factor β-induced protein (TGFBIp) that was recently identified as a therapeutic target for sepsis, and designed TGFBIp acetylation inhibitory peptide (TAIP) that suppresses acetylation of lysine 676 in TGFBIp. To improve bioavailability and biodegradation of the peptide, TAIP was conjugated to polyamidoamine (PAMAM) dendrimers. Additionally, the cell-penetrating peptide (CPP) was conjugated to the TAIP-modified PAMAM dendrimers for the intracellular delivery of TGFBIp. The resulting nanostructures, decorated with TAIP and CPP via poly(ethylene glycol) linkage, improved the mortality and organ damage in the septic mouse model and suppressed lipopolysaccharide-activated severe vascular inflammatory responses in endothelial cells. Thus, the dendrimer-based nanostructures for delivery of TAIP using CPP show great promise in practical applications in sepsis therapy. [ABSTRACT FROM AUTHOR]

High-voltage operation of LiNi x Mn y Co 1-x-y O 2 (NMC) cathodes is gaining significant attention for advanced lithium-ion batteries (LIBs) with high energy density that can enable energy conversion and storage for mid- and large-scale applications. However, it is challenging to mitigate the detrimental effects of rapid capacity fading over short cycle durations because of severe continuous electrolyte decomposition and instability at the electrode surface, which are generally present in high cut-off voltage cycling. In this study, the unprecedented sulfate-based compound, [4,4-bi(1,3,2-dioxathiolane)] 2,2,2,2-tetraoxide (BDTT), is employed as a novel cathode stabilizing additive combined with vinylene carbonate, a well-known anode stabilizing additive, to enhance the electrochemical performance of a LiNi 0.5 Mn 0.3 Co 0.2 O 2 /graphite full cell. A synergistic effect of the dual cathode and anode stabilizer additive inclusion on the cycling performance results in high capacity and 86% of capacity retention for long operation (200 cycles). Prevention of IR drop and polarization in both charge and discharge cycles are achieved via dual additive combination. The results clearly indicate the importance of developing new additives and the potential of additive combination for improved high-voltage lithium-ion battery performance. Image 1 • Novel sulfate-type additive, BDTT, is fabricated and introduced in full cell with VC. • Synergistic effects observed at high voltage operation using BDTT and VC additives. • Excellent cycle performance is achieved with additive-containing electrolyte. • Well-selected additive mixtures suppress impedance rise and polarization. [ABSTRACT FROM AUTHOR]