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Breast cancer risk continues to increase post menopause. Anti-estrogen therapies are available to prevent postmenopausal breast cancer in high-risk women. However, their adverse effects have reduced acceptability and overall success in cancer prevention. Natural products such as hops (Humulus lupulus) and three pharmacopeial licorice (Glycyrrhiza) species have demonstrated estrogenic and chemopreventive properties, but little is known regarding their effects on aromatase expression and activity as well as pro-proliferation pathways in human breast tissue. We show that Gycyrrhiza inflata (GI) has the highest aromatase inhibition potency among these plant extracts. Moreover, phytoestrogens such as liquiritigenin which is common in all licorice species have potent aromatase inhibitory activity, which is further supported by computational docking of their structures in the binding pocket of aromatase. In addition, GI extract and liquiritigenin suppress aromatase expression in the breast tissue of high-risk postmenopausal women. Although liquiritigenin has estrogenic effects in vitro, with preferential activity through estrogen receptor (ER)-β, it reduces estradiol-induced uterine growth in vivo. It downregulates RNA translation, protein biosynthesis, and metabolism in high-risk women's breast tissue. Finally, it reduces the rate of MCF-7 cell proliferation, with repeated dosing. Collectively, these data suggest that liquiritigenin has breast cancer prevention potential for high-risk postmenopausal women. [ABSTRACT FROM AUTHOR]

Point-of-need (PON) diagnostics offer promising methods to gather information relevant to health and safety on-site without the requirement for a fully equipped laboratory. In this review, we discuss how liquid-infused surfaces offer a promising platform to expand the capabilities of PON devices in the areas of biological sample preparation and system integration, providing new methods of controlling the movement of droplets and facilitating detection of biological and chemical compounds contained therein. Modifications to the underlying surface structure can be used to passively control the direction of droplet movement, and the careful selection of responsive solid substrates and/or overlying liquids can allow active control through induced temperature gradients, electrical stimulation, and exposure to magnetic fields. Recent work leveraging other advantages of liquid-infused systems such as ultra-low friction, noncoalescence of droplets, and liquid–liquid patterning has demonstrated the unique ways in which this approach can be used to both enhance current detection methods as well as enable new ones. Together, these recent developments in the manipulation of droplets on liquid-infused surfaces point to their significant potential for furthering the capacity of PON devices for both biological and environmental samples. Image 1 [ABSTRACT FROM AUTHOR]

Many women consider botanical dietary supplements (BDSs) as safe alternatives to hormone therapy for menopausal symptoms. However, the effect of BDSs on breast cancer risk is largely unknown. In the estrogen chemical carcinogenesis pathway, P450 1B1 metabolizes estrogens to 4-hydroxylated catechols, which are oxidized to genotoxic quinones that initiate and promote breast cancer. In contrast, P450 1A1 catalyzed 2-hydroxylation represents a detoxification pathway. The current study evaluated the effects of red clover, a popular BDS used for women's health, and its isoflavones, biochanin A (BA), formononetin (FN), genistein (GN), and daidzein (DZ), on estrogen metabolism. The methoxy estrogen metabolites (2-MeOEk1, 4-MeOEk1) were measured by LC-MS/MS, and CYP1A1 and CYP1B1 gene expression was analyzed by qPCR. Nonmalignant ER-negative breast epithelial cells (MCF-10A) and ER-positive breast cancer cells (MCF-7) were derived from normal breast epithelial tissue and ER+ breast cancer tissue. Red clover extract (RCE, 10 µg/mL) and isoflavones had no effect on estrogen metabolism in MCF-10A cells. However, in MCF-7 cells, RCE treatments downregulated CYP1A1 expression and enhanced genotoxic metabolism (4-MeOEk1/CYP1B1 > 2-MeOEk1/CYP1A1). Experiments with the isoflavones showed that the AhR agonists (BA, FN) preferentially induced CYP1B1 expression as well as 4-MeOEk1. In contrast, the ER agonists (GN, DZ) downregulated CYP1A1 expression likely through an epigenetic mechanism. Finally, the ER antagonist ICI 182,780 potentiated isoflavone-induced XRE-luciferase reporter activity and reversed GN and DZ induced downregulation of CYP1A1 expression. Overall, these studies show that red clover and its isoflavones have differential effects on estrogen metabolism in "normal" vs breast cancer cells. In breast cancer cells, the AhR agonists stimulate genotoxic metabolism, and the ER agonists downregulate the detoxification pathway. These data may suggest that especially breast cancer patients should avoid red clover and isoflavone based BDSs when making choices for menopausal symptom relief. [ABSTRACT FROM AUTHOR]

Virtually all biomaterials are susceptible to biofilm formation and, as a consequence, device-associated infection. The concept of an immobilized liquid surface, termed slippery liquid-infused porous surfaces (SLIPS), represents a new framework for creating a stable, dynamic, omniphobic surface that displays ultralow adhesion and limits bacterial biofilm formation. A widely used biomaterial in clinical care, expanded polytetrafluoroethylene (ePTFE), infused with various perfluorocarbon liquids generated SLIPS surfaces that exhibited a 99% reduction in S . aureus adhesion with preservation of macrophage viability, phagocytosis, and bactericidal function. Notably, SLIPS modification of ePTFE prevents device infection after S . aureus challenge in vivo, while eliciting a significantly attenuated innate immune response. SLIPS-modified implants also decrease macrophage inflammatory cytokine expression in vitro, which likely contributed to the presence of a thinner fibrous capsule in the absence of bacterial challenge. SLIPS is an easily implementable technology that provides a promising approach to substantially reduce the risk of device infection and associated patient morbidity, as well as health care costs. [ABSTRACT FROM AUTHOR]

• Phenolic acid esterification yields antioxidant Cellulose Nanofibril (CNF) films. • Esterified CNF films have active functionality and extend shelf life of fatty foods. • Hydrophobicity of CNF films improved after phenolic acid esterification. • Esterification does not negatively affect mechanical properties of CNF films. Cellulose nanofibril (CNF) is a natural biodegradable biopolymer with excellent mechanical and barrier properties. However, it is susceptible to moisture-induced deterioration of its properties. Attachment of phenolic acids can improve its hydrophobicity and provide additional active functionalities such as antioxidant properties. In this study, CNF films were esterified to vanillic and syringic acid through two different reaction mechanisms. The films were investigated for evidence of modification, hydrophobicity, mechanical properties, crystallinity, thermal stability, and antioxidant properties. Results indicate that esterification with vanillic and syringic acids imparted antioxidant activity to CNF films, with a significantly higher ABTS+· scavenging activity (76 ± 18%) when compared to control CNF films (30 ± 6%). Similarly, esterification of phenolic acids significantly improved the hydrophobicity of the films with a water contact angle of 94 ± 3° when compared to control CNF films (46 ± 5°). Covalent attachment of phenolic acids can improve hydrophobicity while providing additional functionality to CNF important for food packaging applications. [ABSTRACT FROM AUTHOR]

Abstract: Wood-decaying basidiomycetes are some of the most effective bioconverters of lignocellulose in nature, however the way they alter wood crystalline cellulose on a molecular level is still not well understood. To address this, we examined and compared changes in wood undergoing decay by two species of brown rot fungi, Gloeophyllum trabeum and Meruliporia incrassata, and two species of white rot fungi, Irpex lacteus and Pycnoporus sanguineus, using X-ray diffraction (XRD) and 13C solid-state nuclear magnetic resonance (NMR) spectroscopy. The overall percent crystallinity in wood undergoing decay by M. incrassata, G. trabeum, and I. lacteus appeared to decrease according to the stage of decay, while in wood decayed by P. sanguineus the crystallinity was found to increase during some stages of degradation. This result is suggested to be potentially due to the different decay strategies employed by these fungi. The average spacing between the 200 cellulose crystal planes was significantly decreased in wood degraded by brown rot, whereas changes observed in wood degraded by the two white rot fungi examined varied according to the selectivity for lignin. The conclusions were supported by a quantitative analysis of the structural components in the wood before and during decay confirming the distinct differences observed for brown and white rot fungi. The results from this study were consistent with differences in degradation methods previously reported among fungal species, specifically more non-enzymatic degradation in brown rot versus more enzymatic degradation in white rot. [Copyright &y& Elsevier]

Abstract: Films of surface-bound homo-oligonucleotides on gold were hybridized and subjected to rinses using various volumes of water in preparation for ex situ spectroscopic analysis performed by high-resolution X-ray photoelectron spectroscopy, near-edge X-ray absorption fine structure spectroscopy, and infrared reflection–absorption spectroscopy. It was found that films rinsed with 0.5mL of water contained well-ordered DNA hybrids, while films rinsed with greater volumes (1 and 2mL) showed a decreased number of hybrids and a significant disruption of their intactness and order. These results illustrate the importance of taking into account preparation procedures when interpreting ex situ spectroscopic data of such systems. [Copyright &y& Elsevier]

Abstract: Small, low molecular weight, non-enzymatic compounds have been linked to the early stages of brown rot decay as the enzymes involved with holocellulose degradation are too large to penetrate the S3 layer of intact wood cells. We investigated the most notable of these compounds, i.e. hydrogen peroxide, iron, and oxalic acid. The former two are involved in the Fenton reaction in which they react to form hydroxyl radicals, which cause an accelerated depolymerization in cotton cellulose. We found the same reaction to be caused by both iron Fe3+ and Fe2+. A 10 mM oxalic acid solution showed significant depolymerization effect on cotton cellulose. An oxalic acid/sodium oxalate buffered pH gradient had an inhibitory effect on the reduction of cellulose polymers at increased pH values. The organic iron chelator, EDTA, was found to promote depolymerization of cellulose in combination with Fenton’s reagents, but inhibited the effect of oxalic acid in the absence of iron and hydrogen peroxide. Manganese was tested to see if metals other than iron could generate a significant impact on the degree of polymerization (DP) in cotton cellulose. Depolymerizing properties comparable to iron were seen. The results confirm that low molecular weight metabolites are capable of depolymerizing cellulose and suggest an importance of these mechanisms during incipient decay by brown rot fungi. [Copyright &y& Elsevier]

Abstract: Hydrophilic and hydrophobic self-assembled monolayers of alkanethiols were examined in air and in water using sum-frequency-generation spectroscopy (SFG). Hydrophilic films showed significant changes in peak intensity and position upon exposure to water, indicating extensive interaction of water molecules with the film. Spectra of hydrophobic films were similar in air and water, indicating only weak interactions of water with the film. Density Functional Theory (DFT) calculations were also performed to identify the vibrational modes contributing most significantly to the observed effects. These results demonstrate how SFG can be used to detect the interaction of water with molecules in thin films at interfaces. [Copyright &y& Elsevier]

Abstract: The degradation of wood by brown rot fungi has been studied intensely for many years in order to facilitate the preservation of in-service wood. In this work we used X-ray diffraction to examine changes in wood cellulose crystallinity caused by the brown rot fungi Gloeophyllum trabeum, Coniophora puteana, and two isolates of Serpula lacrymans. All fungi increased apparent percent crystallinity early in the decay process while decreasing total amounts of both crystalline and amorphous material. Data also showed an apparent decrease of approximately 0.05Å in the average spacing of the crystal planes in all degraded samples after roughly 20% weight loss, as well as a decrease in the average observed relative peak width at 2θ =22.2°. These results may indicate a disruption of the outer most semi-crystalline cellulose chains comprising the wood microfibril. X-ray diffraction analysis of wood subjected to biological attack by fungi may provide insight into degradative processes and wood cellulose structure. [Copyright &y& Elsevier]

In botanical extracts, highly abundant constituents can mask or dilute the effects of other, and often, more relevant biologically active compounds. To facilitate the rational chemical and biological assessment of these natural products with wide usage in human health, we introduced the DESIGNER approach of D epleting and E nriching S elective I ngredients to G enerate N ormalized E xtract R esources. The present study applied this concept to clinical Red Clover Extract (RCE) and combined phytochemical and biological methodology to help rationalize the utility of RCE supplements for symptom management in postmenopausal women. Previous work has demonstrated that RCE reduces estrogen detoxification pathways in breast cancer cells (MCF-7) and, thus, may serve to negatively affect estrogen metabolism-induced chemical carcinogenesis. Clinical RCE contains ca. 30% of biochanin A and formononetin, which potentially mask activities of less abundant compounds. These two isoflavonoids are aryl hydrocarbon receptor (AhR) agonists that activate P450 1A1, responsible for estrogen detoxification, and P450 1B1, producing genotoxic estrogen metabolites in female breast cells. Clinical RCE also contains the potent phytoestrogen, genistein, that downregulates P450 1A1, thereby reducing estrogen detoxification. To identify less abundant bioactive constituents, countercurrent separation (CCS) of a clinical RCE yielded selective lipophilic to hydrophilic metabolites in six enriched DESIGNER fractions (DFs 01–06). Unlike solid-phase chromatography, CCS prevented any potential loss of minor constituents or residual complexity (RC) and enabled the polarity-based enrichment of certain constituents. Systematic analysis of estrogen detoxification pathways (ERα-degradation, AhR activation, CYP1A1 / CYP1B1 induction and activity) of the DFs uncovered masked bioactivity of minor/less abundant constituents including irilone. These data will allow the optimization of RCE with respect to estrogen detoxification properties. The DFs revealed distinct biological activities between less abundant bioactives. The present results can inspire future carefully designed extracts with phytochemical profiles that are optimized to increase in estrogen detoxification pathways and, thereby, promote resilience in women with high-risk for breast cancer. The DESIGNER approach helps to establish links between complex chemical makeup, botanical safety and possible efficacy parameters, yields candidate DFs for (pre)clinical studies, and reveals the contribution of minor phytoconstituents to the overall safety and bioactivity of botanicals, such as resilience promoting activities relevant to women's health. Countercurrent separation of clinical red clover extract yielded DESIGNER fractions enriched in less abundant constituents that relate to red clover's estrogen detoxification and resilience enhancing properties. [Display omitted] • Applied DESIGNER concept to clinical Red Clover Extract (RCE). • Countercurrent separation (CCS) prevented any potential loss of minor constituents. • Identified distinct biological activities of minor bioactives. • Reveals relevance of minor phytoconstituents to botanical safety and efficacy. [ABSTRACT FROM AUTHOR]

Removing biofouling is a significant challenge in membrane filtration. Here, the presence of a surface-immobilized layer of lubricant is shown to result in flux recovery in protein-fouled polytetrafluoroethylene (PTFE) membranes. Recovery of these liquid-gated membranes (LGMs) occurs during a 15- or 30-min cessation of flow, or rest, and results in up to 60% recovery of clean-membrane flux compared to 10% in membranes with no lubricant layer. Repeated filtration of a 2.5 g L −1 solution of whey protein and subsequent resting continues to result in recovery of flow over 12 cycles. Resting does not result in flux recovery in LGMs fouled with bacterial biofilms. Nevertheless, it is found that flow can be recovered in biofilm-fouled membranes through exposure to an air-water interface. This work demonstrates the potential for liquid gating to facilitate passive flux recovery in biofouled membranes, with promising applications in industry processes. [ABSTRACT FROM AUTHOR]

Humulus lupulus L. (hops) is a popular botanical dietary supplement used by women as a sleep aid and for postmenopausal symptom relief. In addition to its efficacy for menopausal symptoms, hops can also modulate the chemical estrogen carcinogenesis pathway and potentially protect women from breast cancer. In the present study, an enriched hop extract and the key bioactive compounds [6-prenylnarigenin (6-PN), 8-prenylnarigenin (8-PN), isoxanthohumol (IX), and xanthohumol (XH)] were tested for their effects on estrogen metabolism in breast cells (MCF-10A and MCF-7). The methoxyestrones (2-/4-MeOE1) were analyzed as biomarkers for the nontoxic P450 1A1 catalyzed 2-hydroxylation and the genotoxic P450 1B1 catalyzed 4-hydroxylation pathways, respectively. The results indicated that the hop extract and 6-PN preferentially induced the 2-hydroxylation pathway in both cell lines. 8-PN only showed slight up-regulation of metabolism in MCF-7 cells, whereas IX and XH did not have significant effects in either cell line. To further explore the influence of hops and its bioactive marker compounds on P450 1A1/1B1, mRNA expression and ethoxyresorufin O-dealkylase (EROD) activity were measured. The results correlated with the metabolism data and showed that hop extract and 6-PN preferentially enhanced P450 1A1 mRNA expression and increased P450 1A1/1B1 activity. The aryl hydrocarbon receptor (AhR) activation by the isolated compounds was tested using xenobiotic response element (XRE) luciferase construct transfected cells. 6-PN was found to be an AhR agonist that significantly induced XRE activation and inhibited 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induced XRE activity. 6-PN mediated induction of EROD activity was also inhibited by the AhR antagonist CH223191. These data show that the hop extract and 6-PN preferentially enhance the nontoxic estrogen 2-hydroxylation pathway through AhR mediated up-regulation of P450 1A1, which further emphasizes the importance of standardization of botanical extracts to multiple chemical markers for both safety and desired bioactivity. [ABSTRACT FROM AUTHOR]

Bio-based lightweight materials are promising replacements for petroleum-based foams in building and packaging applications. In this work, we developed a surfactant-assisted foam-forming method to manufacture lightweight materials based on lignocellulosic fibers (thermomechanical pulp (TMP), refined wood fibers (RWF) and pine flour (PF)) enabled by cellulose nanofibrils (CNFs). Sodium dodecyl sulfate (SDS) or cetyltrimethylammonium bromide (CTAB) at 1 g/L concentration was mixed with different concentrations of CNFs in a blender followed by the addition of a pre-determined amount of TMP, RWF or PF. The preparation of hybrid foams using TMP/PF, TMP/RWF, and TMP/PF/RWF at different weight fractions was also investigated. Results showed that among the three tested natural fibers, TMP was the best for the preparation of low-density foamed materials, with densities ranging from 11 to 45 kg/m3 in the case of foams made with SDS and 16–90 kg/km3 for those made with CTAB. Thermal conductivity of the prepared foams was between 0.031 W/m.K and 0.055 W/m.K depending on the density and the porosity of the foams. Foams made with high solids content (4–6 wt%) exhibited excellent sound absorption coefficients (0.96–1 at 3500 Hz). Water stability and mechanical properties of the resulting bio-foams were significantly improved when increasing CNF and solids contents. All foams exhibited antifungal properties against Trametes versicolor. Additionally, the hybrid foams exhibited good and competitive properties. These low-density foams enabled by the excellent bonding capability of CNFs could thus be potentially used to provide antifungal resistance as well as acoustic and thermal insulation. [Display omitted] • Foam forming method was used to develop ultra-low density TMP/CNF foams. • Anionic (SDS) and cationic (CTAB) foaming agents were used in foam formulations. • TMP/CNF foams provided antifungal resistance, acoustic and thermal insulation. • Hybrid foams from different fibers showed good and competitive properties. • Water stability and foams' strength were improved with CNF and solid contents. [ABSTRACT FROM AUTHOR]

Omniphobic coatings are designed to repel a wide range of liquids without leaving stains on the surface. A practical coating should exhibit stable repellency, show no interference with color or transparency of the underlying substrate and, ideally, be deposited in a simple process on arbitrarily shaped surfaces. We use layer-by-layer (LbL) deposition of negatively charged silica nanoparticles and positively charged polyelectrolytes to create nanoscale surface structures that are further surface-functionalized with fluorinated silanes and infiltrated with fluorinated oil, forming a smooth, highly repellent coating on surfaces of different materials and shapes. We show that four or more LbL cycles introduce sufficient surface roughness to effectively immobilize the lubricant into the nanoporous coating and provide a stable liquid interface that repels water, low-surface-tension liquids and complex fluids. The absence of hierarchical structures and the small size of the silica nanoparticles enables complete transparency of the coating, with light transmittance exceeding that of normal glass. The coating is mechanically robust, maintains its repellency after exposure to continuous flow for several days and prevents adsorption of streptavidin as a model protein. The LbL process is conceptually simple, of low cost, environmentally benign, scalable, automatable and therefore may present an efficient synthetic route to non-fouling materials. [ABSTRACT FROM AUTHOR]

Kinase inhibitors ( KIs) represent an important group of anticancer drugs, and many of them are substrates and inhibitors of human cytochrome P450s ( CYPs), raising the potential of harmful drug interactions. This study investigated the effect of a library of KIs ( n = 91) including 11 FDA-approved KIs on human CYP1A2, 2D6, 2C9, and 3A4 using high-throughput screening kits and the binding modes with CYPs using the Discovery Studio program 3.1. The KIs exhibited differential inhibitory effect on CYP1A2, 2D6, 2C9, and 3A4, while some of them showed activating effect on CYP2C9 and 3A4. For example, SP 600125 was a potent inhibitor for CYP1A2, but enhanced the activity of CYP2C9 fourfolds. Among the 80 KIs that are not used clinically, about 13% showed significant inhibition to CYPs. Nilotinib, sunitinib, and imatinib were found to be potent CYP1A2 inhibitor. Our docking studies have demonstrated the importance of multiple amino acid residues in the active sites of CYP1A2, 2C9, 2D6, and 3A4 in binding with various KIs. Finally, the in vitro data were used to predict potential KI-drug interactions. These findings indicate that many KIs can serve as CYP inhibitors, and further studies are needed to examine the clinical impact. [ABSTRACT FROM AUTHOR]

Microbial adhesion to medical devices is common for hospital-acquired infections, particularly for urinary catheters. If not properly treated these infections cause complications and exacerbate antimicrobial resistance. Catheter use elicits bladder inflammation, releasing host serum proteins, including fibrinogen (Fg), into the bladder, which deposit on the urinary catheter. Enterococcus faecalis uses Fg as a scaffold to bind and persist in the bladder despite antibiotic treatments. Inhibition of Fg-pathogen interaction significantly reduces infection. Here, we show deposited Fg is advantageous for uropathogens E. faecalis, Escherichia coli, Pseudomonas aeruginosa, K. pneumoniae, A. baumannii, and C. albicans, suggesting that targeting catheter protein deposition may reduce colonization creating an effective intervention for catheter-associated urinary tract infections (CAUTIs). In a mouse model of CAUTI, host-protein deposition was reduced, using liquid-infused silicone catheters, resulting in decreased colonization on catheters, in bladders, and dissemination in vivo. Furthermore, proteomics revealed a significant decrease in deposition of host-secreted proteins on liquid-infused catheter surfaces. Our findings suggest targeting microbial-binding scaffolds may be an effective antibiotic-sparing intervention for use against CAUTIs and other medical device infections. [ABSTRACT FROM AUTHOR]

Two sample cells designed specifically for sum-frequency-generation (SFG) measurements at the solid/liquid interface were developed: one thin-layer analysis cell allowing measurement of films on reflective metallic surfaces through a micrometer layer of solution and one spectroelectrochemical cell allowing investigation of processes at the indium tin oxide/solution interface. Both sample cells are described in detail and data illustrating the capabilities of each are shown. To further improve measurements at solid/liquid interfaces, the broadband SFG system was modified to include a reference beam which can be measured simultaneously with the sample signal, permitting background correction of SFG spectra in real time. Sensitivity tests of this system yielded a signal-to-noise ratio of 100 at a surface coverage of 0.2 molecules/nm2. Details on data analysis routines, pulse shaping methods of the visible beam, as well as the design of a purging chamber and sample stage setup are presented. These descriptions will be useful to those planning to set up a SFG spectrometer or seeking to optimize their own SFG systems for measurements of solid/liquid interfaces. [ABSTRACT FROM AUTHOR]

Microfluidic technologies have enormous potential to offer breakthrough solutions across a wide range of applications. However, the rate of scale-up and commercialization of these technologies has lagged significantly behind promising breakthrough developments in the lab, due at least in part to the problems presented by transitioning from benchtop fabrication methods to mass-manufacturing. In this work, we develop and validate a method to create functional microfluidic prototype devices using 3D printed masters in an industrial-scale roll-to-roll continuous casting process. There were no significant difference in mixing performance between the roll-to-roll cast devices and the PDMS controls in fluidic mixing tests. Furthermore, the casting process provided information on the suitability of the prototype microfluidic patterns for scale-up. This work represents an important step in the realization of high-volume prototyping and manufacturing of microfluidic patterns for use across a broad range of applications. [ABSTRACT FROM AUTHOR]

Camera-guided instruments, such as endoscopes, have become an essential component of contemporary medicine. The 15-20 million endoscopies performed every year in the United States alone demonstrate the tremendous impact of this technology. However, doctors heavily rely on the visual feedback provided by the endoscope camera, which is routinely compromised when body fluids and fogging occlude the lens, requiring lengthy cleaning procedures that include irrigation, tissue rubbing, suction, and even temporary removal of the endoscope for external cleaning. Bronchoscopies are especially affected because they are performed on delicate tissue, in high-humidity environments with exposure to extremely adhesive biological fluids such as mucus and blood. Here, we present a repellent, liquidinfused coating on an endoscope lens capable of preventing vision loss after repeated submersions in blood and mucus. The material properties of the coating, including conformability, mechanical adhesion, transparency, oil type, and biocompatibility, were optimized in comprehensive in vitro and ex vivo studies. Extensive bronchoscopy procedures performed in vivo on porcine lungs showed significantly reduced fouling, resulting in either unnecessary or ~10-15 times shorter and less intensive lens clearing procedures compared with an untreated endoscope. We believe that the material developed in this study opens up opportunities in the design of next-generation endoscopes that will improve visual field, display unprecedented antibacterial and antifouling properties, reduce the duration of the procedure, and enable visualization of currently unreachable parts of the body, thus offering enormous potential for disease diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Thrombosis and biofouling of extracorporeal circuits and indwelling medical devices cause significant morbidity and mortality worldwide. We apply a bioinspired, omniphobic coating to tubing and catheters and show that it completely repels blood and suppresses biofilm formation. The coating is a covalently tethered, flexible molecular layer of perfluorocarbon, which holds a thin liquid film of medical-grade perfluorocarbon on the surface. This coating prevents fibrin attachment, reduces platelet adhesion and activation, suppresses biofilm formation and is stable under blood flow in vitro. Surface-coated medical-grade tubing and catheters, assembled into arteriovenous shunts and implanted in pigs, remain patent for at least 8 h without anticoagulation. This surface-coating technology could reduce the use of anticoagulants in patients and help to prevent thrombotic occlusion and biofouling of medical devices. [ABSTRACT FROM AUTHOR]

Fungal and enzymatic pre-treatments have long been used to activate the surface of lignocellulosic biomass particles or fibers to promote adhesion or develop novel composite materials and other products. Research into mycelium-based bio-composites, i.e. products in which constituents are bonded by fungal mycelium, is quite new and still growing. There has also been a significant amount of attention given to these materials by the industry and private sector. These bio-composites can be produced by enzymatically or fungally treating lignoicellulosic substrates and then either molding them into a shape and letting the fungus grow or, alternatively, by hot-pressing the substrate into a panel product. This review article focuses on hot-pressed, higher density lignocellulosic bio-composites produced following enzymatic or fungal pretreatment. The definitions, raw materials, processing procedures, material properties, factors governing product properties, and potential adhesion mechanisms are summarized and discussed. Finally, current commercial products are introduced and roadblocks in the way of further development are presented along with the identification of knowledge gaps. [Display omitted] • Comprehensive review of fungal/enzymatic pretreatments of lignocellulosics. • Critical review focused on pretreatments applied to hot-pressed bio-composites. • Such pretreatments can enhance bonding by altering raw material properties. • Roadblocks to industrial adoption are moisture resistance, process cost/efficiency. [ABSTRACT FROM AUTHOR]

The structure and stability of single- and double-stranded DNA hybrids immobilized on gold are strongly affected by nucleotide-surface interactions. To systematically analyze the effects of these interactions, a set of model DNA hybrids was prepared in conformations that ranged from end-tethered double-stranded to directly adsorbed single-stranded (hairpins) and characterized by surface plasmon resonance (SPR) imaging, X-ray photoelectron spectroscopy (XPS), fluorescence microscopy, and near edge X-ray absorption fine structure (NEXAFS) spectroscopy. The stabilities of these hybrids were evaluated by exposure to a series of stringency rinses in solutions of successively lower ionic strength and by competitive hybridization experiments. In all cases, directly adsorbed DNA hybrids are found to be significantly less stable than either free or end-tethered hybrids. The surface-induced weakening and the associated asymmetry in hybridization responses of the two strands forming hairpin stems are most pronounced for single-stranded hairpins containing blocks of m adenine (A) nucleotides and n thymine (T) nucleotides, which have high and low affinity for gold surfaces, respectively. The results allow a qualitative scale of relative stabilities to be developed for DNA hybrids on surfaces. Additionally, the results suggest a route for selectively weakening portions of immobilized DNA hybrids and for introducing asymmetric hybridization responses by using sequence design to control nucleotide-surface interactions-a strategy that may be used in advanced biosensors and in switches or other active elements in DNA-based nanotechnology. [ABSTRACT FROM AUTHOR]

Formation of unwanted deposits on steels during their interaction with liquids is an inherent problem that often leads to corrosion, biofouling and results in reduction in durability and function. Here we report a new route to form anti-fouling steel surfaces by electrodeposition of nanoporous tungsten oxide (TO) films. TO-modified steels are as mechanically durable as bare steel and highly tolerant to compressive and tensile stresses due to chemical bonding to the substrate and island-like morphology. When inherently superhydrophilic TO coatings are converted to superhydrophobic, they remain non-wetting even after impingement with yttria-stabilized-zirconia particles, or exposure to ultraviolet light and extreme temperatures. Upon lubrication, these surfaces display omniphobicity against highly contaminating media retaining hitherto unseen mechanical durability. To illustrate the applicability of such a durable coating in biofouling conditions, we modified naval construction steels and surgical instruments and demonstrated significantly reduced marine algal film adhesion, Escherichia coli attachment and blood staining. [ABSTRACT FROM AUTHOR]