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The stable nitroxide radical TEMPO [(2,2,6,6-Tetramethylpiperidin-1-yl)oxyl] has a multitude of applications in fields ranging from energy storage to biomedical applications and many more. However, to date, the processes of incorporating nitroxide radicals into thin-film coatings are laborious and not cost-effective, which hinders their wider use in many applications. In contrast, the authors have recently demonstrated the facile method of plasma polymerization of TEMPO into thin-film coatings that retain the stable nitroxide radicals. In this work, we are using three types of mass spectroscopic methods (plasma-mass spectrometry, time of flight secondary ion mass spectrometry, and high-performance liquid chromatography-mass spectrometry) and electron spin resonance to track the fate of the TEMPO molecule from monomer flask through the plasma and inside the resulting coatings. The results of this study demonstrate that TEMPO is a versatile monomer that can be used across different plasma reactors and reliably retain the stable nitroxide radical in the resulting thin-film coatings if certain process conditions are observed, namely, higher process pressures and lower powers.

It has been proposed that some neuropeptides may be anchored to the cell membranes prior to attaching to the adjacent active sites of transmembrane receptors. The three amphibian skin neuropeptides signiferin 1 [RLCIPYIIPC(OH)] (smooth muscle active and immunomodulator), riparin 1.1 [[RLCIPVIFPC(OH)] (immunomodulator) and rothein 1 [SVSNIPESIGF(OH)] (immunomodulator) act via CCK2 transmembrane receptors. A combination of (31)P and (2)H solid state NMR studies of each of these three peptides in eukaryotic phospholipid models at 25°C shows that rothein 1 does not interact with the membrane at all. In contrast, both of the cyclic disulfides signiferin 1 and riparin 1.1 interact with phospholipid head groups and partially penetrate into the upper leaflet of the model bilayer, but to different extents. These interactions are not sufficiently effective to cause disruption of the lipid bilayer since the peptides are not antimicrobial, anticancer, antifungal nor active against enveloped viruses., (Copyright © 2014. Published by Elsevier Inc.)

Anuran peptides which contain His, including caerin 1.8 (GLFKVLGSVAKHLLPHVVPVIAEKL-NH(2)), caerin 1.2 (GLLGVLGSVAKHVLPHVVPVIAEHL-NH(2)), Ala(15) maculatin 1.1 (GLFGVLAKVAAHVVAIEHF-NH(2)), fallaxidin 4.1 (GLLSFLPKVIGHLIHPPS-OH), riparin 5.1 (IVSYPDDAGEHAHKMG-NH(2)) and signiferin 2.1 (IIGHLIKTALGMLGL-NH(2)), all form MMet(2+) and (M + Met(2+)-2H(+))(2+) cluster ions (where Met is Cu, Mg and Zn) following electrospray ionisation (ESI) in a Waters QTOF 2 mass spectrometer. Peaks due to Cu(II) complexes are always the most abundant relative to other metal complexes. Information concerning metal(2+) connectivity in a complex has been obtained (at least in part) using b and y fragmentation data from ESI collision-induced dissociation tandem mass spectrometry (CID MS/MS). Theoretical calculations, using AMBER version 10, show that MCu(2+) complexes with the membrane active caerin 1.8, Ala(15) maculatin 1.1 and fallaxidin 4.1 are four-coordinate and approximating square planar, with ligands including His and Lys, together with the carbonyl oxygens of particular backbone amide groups. When binding can occur through two His, or one His and one Lys, the His/Lys ligand structure is the more stable for the studied systems. The three-dimensional (3D) structures of the complexes are always different from the previously determined structures of the uncomplexed model peptides (using 2D nuclear magnetic resonance (NMR) spectroscopy in membrane-mimicking solvents like trifluoroethanol/water)., (Copyright © 2011 John Wiley & Sons, Ltd.)

Host defense peptides of 35 species of Australian frogs from the hylids Cyclorana and Litoria, and the myobatrachids Crinia, Limnodynastes and Uperoleia have been identified. The biological activities of the majority of these peptides have been determined and include hormones, neuropeptides, opioids, immunomodulators, membrane active peptides [including antimicrobial, anticancer, antiviral (enveloped viruses like HIV and Herpes) and antifungal peptides], neuronal nitric oxide synthase inhibitors, pheromones and individual peptides with other specific activities. The host defense peptide skin profile can be diagnostic at both the species and higher taxonomic levels; for example, species of Crinia, Litoria and Uperoleia each produce quite different types of peptides. Species of Cyclorana and Limnodynastes are more difficult to characterize by skin peptides alone: species of both genera produce similar peptides with no apparent activity. The skin peptide profiles of frogs from the genera Crinia, Litoria and Uperoleia may be used together with morphological and cognate methods, to differentiate between sub-species and even different population clusters of the same species. Nucleotide sequencing of cDNAs of precursors (pre-pro peptides) of bioactive peptides from the skin glands of various species of the genus Litoria show that the majority of these peptides originated from a single ancestor gene before the break away of Australia from Gondwana. The exceptions are the caerulein neuropeptides {e.g. caerulein [pEQDY(SO(3)H)TGWMDF(NH(2))]} which have a different origin to that of other Litoria peptides. Disulfide containing peptides from skin glands of species of Crinia show a different evolutionary route to peptides from species of Litoria., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Selected carbanions react with carbon disulfide in a modified LCQ ion trap mass spectrometer to form adducts, which when collisionally activated, decompose by processes which in some cases identify the structures of the original carbanions. For example (i) C(6)H(5)(-) + CS(2)--> C(6)H(5)CS(2)(-)--> C(6)H(5)S(-) + CS, occurs through a 3-membered ring ipso transition state, and (ii) the reaction between C(6)H(5)CH(2)(-) and CS(2) gives an adduct which loses H(2)S, whereas the adduct(s) formed between o-CH(3)C(6)H(5)(-) and CS(2) loses H(2)S and CS. Finally, it is shown that decarboxylation of C(6)H(5)CH(2)CH(2)CO(2)(-) produces the beta-phenylethyl anion (PhCH(2)CH(2)(-)), and that this thermalized anion reacts with CS(2) to form C(6)H(5)CH(2)CH(2)CS(2)(-) which when energized fragments specifically by the process C(6)H(5)CH(2)CH(2)CS(2)(-)--> C(6)H(5)CH(2)(-)CHC(S)SH --> [(C(6)H(5)CH(2)CH[double bond, length as m-dash]C[double bond, length as m-dash]S) (-)SH] --> C(6)H(5)CH(2)CCS(-) + H(2)S. Experimental findings of processes (ii) and (iii) were aided by deuterium labelling studies, and all reaction profiles were studied by theoretical calculations at the UCCSD(T)/6-31+G(d,p)//B3LYP/6-31+G(d,p) level of theory unless indicated to the contrary.

The solution structure of fallaxidin 4.1a, a C-terminal amidated analogue of fallaxidin 4.1, a cationic antimicrobial peptide isolated from the amphibian Litoria fallax, has been determined by nuclear magnetic resonance (NMR). In zwitterionic dodecylphosphocholine (DPC) micelles, fallaxidin 4.1a adopted a partially helical structure with random coil characteristics. The flexibility of the structure may enhance the binding and penetration upon interaction with microbial membranes. Solid-state (31)P and (2)H NMR was used to investigate the effects of fallaxidin 4.1a on the dynamics of phospholipid membranes, using acyl chain deuterated zwitterionic dimyristoylphosphatidylcholine (DMPC-d(54)) and anionic dimyristoylphosphatidylglycerol (DMPG) multilamellar vesicles. In DMPC-d(54) vesicle bilayers, fallaxidin 4.1a caused a decrease in the (31)P chemical shift anisotropy (CSA), and a decrease in deuterium order parameters from the upper acyl chain region, indicating increased lipid motion about the phosphate headgroups. Conversely, for DMPC-d(54)/DMPG, two (31)P CSA were observed due to a lateral phase separation of the two lipids and/or differing headgroup orientations in the presence of fallaxidin 4.1a, with a preferential interaction with DMPG. Little effect on the deuterated acyl chain order parameters was observed in the d(54)-DMPC/DMPG model membranes. Real time quartz crystal microbalance analyses of fallaxidin 4.1a addition to DMPC and DMPC/DMPG supported lipid bilayers together with the NMR results indicated transmembrane pore formation in DMPC/DMPG membranes and peptide insertion followed by disruption at a threshold concentration in DMPC membranes. The different interactions observed with "mammalian" (DMPC) and "bacterial" (DMPC/DMPG) model membranes imply fallaxidin 4.1a may be a useful antimicrobial peptide, with preferential cytolytic activity toward prokaryotic organisms at low peptide concentrations (<5 microM).

Two species of tree frog of the genus Litoria, namely L. splendida and L. rothii have been reported to change the compositions of their host-defence skin peptide profiles in summer and winter. L. splendida produces the potent smooth muscle active caerulein [pEQDY(SO(3)H)TGWMDF-NH(2)] in summer, but in winter much of the caerulein is hydrolysed to the less active desulfated form; in addition, caerulein 1.2 [pEQDY(SO(3)H)TGWFDF-NH(2)] (which has only some 50% of the smooth muscle activity of caerulein) is released and acts via CCK2R. In contrast, Litoria rothii shows a most unexpected seasonal change of peptides. In summer it exudes caerulein together with a range of potent caerin antimicrobials and nNOS active peptides. In winter, none of the antibiotic or nNOS active caerin peptides are expressed. The major peptides produced by the skin glands in winter are caerulein 1.2 and rothein 1 (SVSNIPESIGF-OH). Like L. splendida, L. rothii has reduced the smooth muscle potency of caerulein by replacing it with caerulein 1.2. Rothein 1 is a lymphocyte proliferator acting via CCK2R. Activity testing and 2D NMR spectra of rothein 1 and some synthetic modifications indicate that both hydrophobic and hydrophilic interactions between rothein 1 and CCK2R are important.

Infrared spectroscopic imaging with 6-10 microm spatial resolution was used to characterize the changes in fracture callus mineral content, carbonate content, mineral crystallinity, and collagen maturity in femurs of 3-month-old ovariectomized rats treated with estrogen (estrogen sufficiency) or vehicle (estrogen deficiency). Comparisons were also made in these animals to cortical bone at a distance from the callus. Analyses at 4, 8, and 12 weeks post fracture demonstrated that healing was accelerated in the estrogen-sufficient animals as demonstrated by increasing mineral content and collagen maturity and decreasing carbonate incorporation.

Osteoporosis is characterized by low-energy fractures resulting from inadequate bone mass and compromised microarchicture. Bone mass is maximized by adequate nutrition and calcium intake, normal menstrual cycles, and appropriate exercises. Low bone density, as determined by dual-energy x-ray absorptiometry, and high bone turnover, as characterized by elevated bone collagen breakdown products, are the primary indicators of bone fragility. Prevention and treatment of osteoporosis should emphasize adequate calcium and vitamin D intake and exercise. In addition, estrogen supplementation and selective estrogen receptor modulators (estrogen antagonists) can enhance bone mass and decrease the risk of spinal fractures, oral and intravenous bisphosphonates can significantly decrease the incidence of both spinal and hip fractures, and antiosteoporotic agents can help rebuild healthy bone.

Attitudes regarding flight deck automation were surveyed in a sample of 5,879 airline pilots from 12 nations. The average difference in endorsement levels across 11 items for pilots flying automated aircraft in 12 nations was 53%, reflecting significant national differences in attitudes on all items, with the largest differences observed for preference and enthusiasm for automation. The range of agreement across nations was on average four times larger than the range of agreement across different airlines within the same nation, and roughly six times larger than the range across pilots of standard and pilots of automated aircraft. Patterns of response are described in terms of dimensions of national culture. Implications of the results for development of safety cultures and culturally sensitive training are discussed.

Advances in refractive surgery have been limited by the measurement technology for determining corneal thickness and curvature. A measurement technique is needed that can provide a detailed corneal thickness and curvature model without contacting the cornea or obstructing the view of the surgeon or surgical equipment. The authors present preliminary results of a method to remotely measure the thickness and curvature of the human cornea at a single point. The method combines ray tracing and interferometry to estimate thickness and curvature in two orthogonal planes in an area less than 100 microns in diameter. This technique has been successfully used to provide very accurate estimates of several thin-shelled test objects. Based upon these results, recommendations are given for further improvement of the technique and extension to a multipoint cornea-modeling system.

Dynamic bone histomorphometry, [3H]thymidine radioautography, and Northern analysis for bone matrix proteins and insulin-like growth factor-I (IGF-I) were performed in calvariae of ovariectomized (OVX) and estrogen-treated OVX rats. Treatment of OVX rats with diethylstilbestrol (DES) for 2 weeks reduced the periosteal mineral apposition rate, osteoblast number, and osteoblast size in calvarial periosteum. DES treatment also reduced the number of preosteoblasts in the S phase of the cell cycle, suggesting that the decrease in osteoblast number was due in part to inhibition of proliferation of osteoprogenitor cells. One week after ovariectomy, there were small increases in mRNA levels for pre pro-alpha 2 (I) subunit of type I collagen (collagen), osteocalcin, and osteonectin and a large increase in the mRNA level for IGF-I. DES treatment resulted in rapid decreases (3 h) in the mRNA levels for osteonectin, osteocalcin, and IGF-I. In contrast, mRNA levels for collagen were virtually unchanged after short term DES treatment. Uterus and liver served as positive and negative control tissues, respectively, for the effects of DES on IGF-I mRNA levels in OVX rats; mRNA levels were increased in uterus and decreased in liver after hormone treatment. We conclude from these studies that estrogen reduces periosteal bone formation by inhibiting both the differentiation and activity of osteoblasts. Furthermore, down-regulation of mRNA levels for IGF-I and bone matrix proteins precedes the changes in dynamic bone histomorphometry.