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The development of microstructures which combine high total surface area and high porosity is crucial for technologies such as electrocatalysis, electrochromics, and sensors. High deposition rate, composition control of deposition, and low processing temperature to retain active compositions are also desirable. To this end, this study describes combining colloidal sol chemistry with a nonthermal atmospheric pressure dielectric barrier discharge plasma jet to print hybrid inorganic/organic tungsten trioxide/oxalic acid (WO3–x/OA) microspheres. Injection of an aerosol of oxalic acid stabilized colloidal tungstic acid into an atmospheric pressure plasma jet results in the deposition of spherical structures in which the colloid is trapped within a plasma-polymerized organic shell. Subsequent low-temperature sintering produces hierarchical spherical shell-like structures comprising tungsten oxide nanosheets. Alteration of the gas flow rate changes the composition of the deposited material. The method has promise for the general preparation from colloidal precursors of porous materials of controlled morphology and composition with hierarchical microstructures, such as are required for applications in electrochemical devices and sensors which need a high ratio of surface area to volume and connectivity throughout the structure, yet also need a microstructure which is open for rapid exchange of reactants. [ABSTRACT FROM AUTHOR]

Nano-sized placental extracellular vesicles (nano-pEVs) are membrane-bound vesicles released into the maternal circulation during pregnancy by the syncytiotrophoblast, which covers the surface of the placenta. The nano-pEV cargo consists of proteins, lipids, and nucleic acids, which reflect the dynamic placental function during gestation. The ability to biopsy circulating nano-pEVs would aid investigations in placental functions, allowing substantial progress in obstetric care. We developed a simple and clean electrochemical methodology for the specific capture and fast release of nano-pEVs using an electrochemically switchable conducting terpolymer-functionalized carbon cloth. The conducting terpolymer was first reduced (at −0.8 V vs Ag/AgCl, 30 s in PBS) to form active thiols, which could then interact with a thiolated CD63 aptamer via oxidation (+1.0 V vs Ag/AgCl, 60 s) in PBS. Conjugation of the aptamer to the conducting terpolymer-coated carbon cloth was confirmed using SEM-EDS, FTIR, and Raman spectroscopy. As a proof of principle, thiolated fluorescently labeled CD63 aptamers were captured and released electrochemically using this technique. Thereafter, the CD63 aptamer-modified carbon cloth showed the specific capture of nano-pEVs and their subsequent release (−0.8 V vs Ag/AgCl, 120 s) following cleavage of the disulfide bond between the aptamer and the reduced terpolymer. This aptamer-modified conducting terpolymer-coated carbon cloth demonstrated good capture and release efficiencies of (2.09 ± 0.26) × 108 and (1.35 ± 0.14) × 108 particles, respectively, per 70 mm2 of the projected area of the terpolymer-coated carbon cloth. Confocal microscopy images clearly differentiated the carbon cloth fibers with captured nano-pEVs from those after the release. To the best of our knowledge, this work has developed for the first time an efficient, rapid, and straightforward methodology for the capture and release of nano-pEVs. This effective methodology could help to quickly determine fetal abnormalities, to diagnose obstetric disease and pathogenesis throughout pregnancy. [ABSTRACT FROM AUTHOR]

The interfacial adsorption of a mouse monoclonal antibody at the hydrophilic siliconoxide/water interface was studied by spectroscopic ellipsometry and neutron reflection. The neutron reflection revealed that the formation of a 40 Angstrom units uniform layer from the adsorbed antibody, indicating a flat-on orientation.

The stacking reactions of the carotenoid molecule peridinins and their aromatic groups are reported. Carotenoids play a pivotal role in photosynthesis, photoprotection and structural stabilization.

The study describes the neutron reflection from glucose oxidase (GOx) layers adsorbed at the aqueous solution-air interface. The GOx work demonstrates the formation of interfacial layers with uniform density distribution, indicating that despite dissociation and deformation no further structural deterioration occurs.

Research has been conducted on the extracts from the sponge Xestospongia exigua, positive for the anti-invasion activity. The identification of the motuporamines responsible for this activity has been carried out via the bioassay-guided fractionation and the details are reported.

Pt additives, finely dispersed over a semiconducting oxide surface, induce a room temperature CO resistance and have shown the sensitivity of the electrical conductivity to the surface state of Pt is demonstrated. The study of BaSnO3 and BaFeO3 that the effect can only be observed in the case where Pt states are observed in the band gap, and the oxide conductivity is dominated by electron exchange with these states.

A detailed computational study of the occurrence of Sb segregation, using Sb(III) and Sb(V) ions on the (110) and (001) surfaces of SnO2, is reported and discussed.

A study was conducted to show that antimony segregation to the surface as Sb(III) in Sn(sub 1-x)Sb(sub x)O2 changes the effect of water vapor on the surface-catalyzed combustion rate of carbon monoxide and the elevated-temperature electrical conductivity. Coprecipitation was carried out to prepare the oxides. A computer-controlled rig was then utilized to determine the electric behavior of pellets under controlled humidity and temperature conditions.

Extracts of the marine sponge Xestospongia exigua, collected in Papua New Guinea, were found to exhibit selective in vitro cytotoxicities against a panel of human cancer cell lines. A mixture of motuporamines and known members of the petrosin and xestospongin/araguspongine class of 3-alkylpiperidine alkaloids were isolated via bioassay-guided fractionation of the Xetospongia exigua. The motuporamines are the first examples of a new family of macrocyclic alkaloids.

The sensitivity of cytochrome P450-1A1 induction in fish as a biomarker for the distribution of 2, 3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and 2,3,7,8-Tetrachlorodibenzofuran (TCDF) was conducted on northern squawfish, cutthroat trout and the common carp. Results indicate that whole body contamination of squawfish in the Portland Harbor was higher than that upstream. All concentrations of TCDD and TCDF were elevated for all species in this area.

New macrolides are isolated from extracts of the marine sponge Spirastrella coccinea collected in Dominica. The structures of macrolides are determined by a combination of spectroscopic analysis and chemical transformations.

Marine invertibrates have been a rich source of antimitotic secondary metabolites. Extracts of marine invertebrates in a cell-based assay, that detects mitotic arrest is screened to discover new antimiotic natural products.

The isolation, structure elucidation and biological activities of the nigricanosides obtained from the green alga Avrainvillea nigricans collected in Dominica are described. The nigricanosides are found to be the first examples of a new class of ether-linked glycoglycerolipids.

A discussion on the spirastrellolide B that contains the C-26 to C-17 fragment is found in spirastrelloide A is presented. Knowledge about the absolute configuration of the spirastrellolide core is expected to enable current efforts toward the total synthesis of this challenging natural product target.

Treatment of the fungal meroterpenoid dhilirolide A (1) with either sodium azide or perchloric acid results in conversion of the dhilirane carbon skeleton of 1 to the 14,15-dinordhilirane carbon skeleton of the products 5-7, with and without concomitant transfer of an acetyl residue to form a C-9 acetate ester. The discovery of these transformations, which are vinylogous retro-Claisen-type condensations, suggests an efficient biogenetic route to 14,15-dinordhiliranes such as dhilirolide K (3). [ABSTRACT FROM AUTHOR]

The new ansa macrolide antibiotics 1 to 4 have been isolated from cultures of a Micromonospora sp. obtained from a marine sediment. Rifamycins 1 and 2 are the first natural ansa macrolides to have a 3-amino substituent. Sporalactams A (3) and B (4) are comprised of a heterocylic core 5 and a 14-membered ansa bridge that are both unprecedented. Sporalactam B (4) shows selective and potent inhibition of Mycobacterium tuberculosis. [ABSTRACT FROM AUTHOR]

Nahuoic acids A-E (1-5) have been isolated from laboratory cultures of a Streptomyces sp. obtained from a tropical marine sediment. The structures of the new polyketides 2-5 were elucidated by analysis of spectroscopic data of the natural products and the chemical derivatives 6 and 7. Nahuoic acids 1-5 are in vitro inhibitors of the histone methyltransferase SETD8, and nahuoic acid A (1) and its pentaacetate derivative 8 inhibit the proliferation of several cancer cells lines in vitro with modest potency. At the IC50 for cancer cell proliferation, nahuoic acid A (1) showed selective inhibition of SETD8 in U2OS osteosarcoma cells that reflect its selectivity against a panel of pure histone methyl transferases. A cell cycle analysis revealed that the cellular toxicity of nahuoic acid A (1) is likely linked to its ability to inhibit SETD8 activity. [ABSTRACT FROM AUTHOR]

Solanioic acid (1), a degraded and rearranged steroid that exhibits in vitro antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA), has been isolated from laboratory cultures of the fungus Rhizoctonia solani obtained from tubers of the plant Cyperus rotundus collected in Sri Lanka. The structure of solanioic acid (1) was elucidated by detailed analysis of NMR data, a single crystal X-ray diffraction analysis of a reduction product 2, and Mosher ester analysis on a derivative of the natural product. Solanioic acid (1) has an unprecedented carbon skeleton. [ABSTRACT FROM AUTHOR]

Extracts of laboratory cultures of the fungus Penicilium purpurogenum obtained from rotting fruit of the tree Averrhoa bilimbi growing in Sri Lanka have yielded 10 new meroterpenoids, dhilirolides E-N (5-14). The structures of the new dhilirolides have been elucidated by analysis of spectroscopic data and a single-crystal X-ray diffraction analysis of dhilirolide L (12). Dhilirolides A-N (1-14) represent the four unprecedented and rearranged dhilirane, isodhilirane, 14,15-dinordhilirane, and 23,24-dinorisodhilirane meroterpenoid carbon skeletons. Stable isotope feeding studies have confirmed the meroterpenoid biogenetic origin of the dhilirolides and provided support for a proposed genesis of the new carbon skeletons. Dhilirolide L (12) showed significant feeding inhibition and sublethal developmental disruption in the cabbage looper Trichoplusia ni, an important agricultural pest, at low concentrations. [ABSTRACT FROM AUTHOR]

A cost-efficient technology for accurate surface ozone monitoring using gas-sensitive semiconducting oxide (GSS) technology, solar power, and automated cell-phone communications was deployed and validated in a 50 sensor test-bed in the Lower Fraser Valley of British Columbia, over 3 months from May-September 2012. Before field deployment, die entire set of instruments was colocated with reference instruments for at least 48 h, comparing hourly averaged data. The standard error of estimate over a typical range 0-50 ppb for the set was 3 ± 2 ppb. Long-term accuracy was assessed over several months by allocation of a subset of ten instruments each at a different reference site. The differences (GSS-reference) of hourly average ozone concentration were normally distributed with mean -1 ppb and standard deviation 6 ppb (6000 measurement pairs). Instrument failures in the field were detected using network correlations and consistency checks on the raw sensor resistance data. Comparisons with modeled spatial O-i fields demonstrate the enhanced monitoring capability of a network that was a hybrid of low-cost and reference instruments, in which GSS sensors are used both to increase station density within a network as well as to extend monitoring into remote areas. This ambitious deployment exposed a number of challenges and lessons, including the logistical effort required to deploy and maintain sites over a summer period, and deficiencies in cell phone communications and battery life. Instrument failures at remote sites suggested that redundancy should be built into the network (especially at critical sites) as well as the possible addition of a "sleep-mode" for GSS monitors. At the network design phase, a more objective approach to optimize interstation distances, and the "information" content of the network is recommended. This study has demonstrated the utility and affbrdability of the GSS technology for a variety of applications, and die effectiveness of this technology as a means substantially and economically to extend the coverage of an air quality monitoring network. Low-cost, neighborhood-scale networks that produce reliable data can be envisaged. [ABSTRACT FROM AUTHOR]

The isolation and structure determination of the novel cyclic papuamides A, B, C and D, HIV-inhibitory and cytotoxic depsipeptides taken from Papua New Guinea collections of Theonella mirabilis and Theonella swinhoei are described. Their structures were observed through a combination of chemical degradation, derivatization and spectroscopic analysis experiments. The anti-HIV activity of T. mirabilis was tracked to a mixture of peptides consisting primarily of papuamides A and B while the cytotoxic activity of T. swinhoei was traced to papuamides A-D.

The histone lysine monomethyltransferase SETD8 is an epigenetic regulator of cell cycle progression. Nahuoic acid A (1), a polyketide produced in culture by a Streptomycessp. obtained from a tropical marine sediment, is the first known selective SAM-competitive inhibitor of SETD8. The structure of nahuoic acid A (1) has been elucidated by chemical transformation and detailed analysis of spectroscopic data. [ABSTRACT FROM AUTHOR]

Two highly modified linear tetrapeptides, padanamides A (1) and B (2), are produced by laboratory cultures of a Streptomycessp. obtained from a marine sediment. Padanamide B is cytotoxic to Jurkat cells, and a chemical genomics analysis using Saccharomyces cerevisiaedeletion mutants suggested that padanamide A inhibits cysteine and methionine biosynthesis or that these amino acids are involved in the yeast’s response to the peptide. [ABSTRACT FROM AUTHOR]