Sex as a Risk Factor for Solar Ultraviolet Radiation Exposure?–Dosimetry in Danish Outdoor Workers

Solar ultraviolet radiation (UVR) exposure is a known risk factor for the development of skin cancer. Heterogeneity in solar UVR exposure may explain the diversity in skin cancer incidence between men and women. This, however, has not previously been investigated in Danish outdoor workers using UVR dosimetry. The aim of this study was to evaluate sex differences in solar UVR dosimetry in Danish outdoor workers on working and leisure days. A cross-sectional design was used to collect dosimetry data during the Danish summer season (May to September). Analysis was based on an electronic questionnaire and dosimetry data from 450 outdoor workers (88 women, 362 men). Dosimetry data were reported as standard erythema dose (SED). The daily median SED (Interquartile range) on working days was 1.6 (2.5) in men and 1.5 (2.1) in women while on leisure days it was 0.5 (1.4) in men and 0.6 (1.3) in women. Analysis by multiple linear regression did not show any association between daily median SED and sex on either working or leisure days. In conclusion, solar UVR exposure in Danish outdoor workers did not vary according to sex.     

Anthocyanins from Fuchsia flowers

Flowers of Fuchsia arborescens, F. boliviana, F. fulgens var. 'Variegata', F. magellanica (Onagraceae) and twenty-nine F. magellanica cultivars contained some of the thirteen anthocyanidin 3,5-diglucosides (six), 3-monoglycosides (five) and 3-(2"-galloylglucosides) (two), which altogether were identified. Peonidin 3-O-(2"-O-galloyl-beta-glucopyranoside), which has not been reported before, was found in F. magellanica and F. fulgens var. 'Variegata'. The various corollas with purple nuances were correlated with a relatively high content of malvidin 3,5-diglucoside. Flower colors were to a large extent correlated with the number of oxygen substituents on the anthocyanidin B-ring of the major anthocyanins.     

Polar compounds isolated from the leaves of Albertisia delagoensis (Menispermaceae)

Aqueous infusions of the leaves of the shrub Albertisia delagoensis (Menispermaceae) are used in South Africa in traditional Zulu medicine to alleviate a variety of symptoms, including fever, and intestinal problems. We report the analysis of such an aqueous extract using the HPLC-NMR technique. A number of polar compounds were identified, including proto-quercitol, nicotinic acid, allantoic acid, 3,4-dihydroxy-benzoic acid, phthalic acid and the aporphine alkaloid derivative roemrefidine. Allantoic acid and roemrefidine have been fully characterised by (1)H- and (13)C-NMR and mass spectrometry. Earlier reports of antiplasmodial activity of roemrefidine and of A. delagoensis extracts are correlated with this study and with the antipyretic properties of neutral aqueous extracts.     

Electrochemistry/liquid chromatography/mass spectrometry as a tool in metabolism studies

Electrochemistry/liquid chromatography/mass spectrometry is a powerful complementary tool for the simulation of the oxidative metabolism of drugs and other xenobiotics.     

Isolation and Structural Elucidation of Armeniaspirols A–C: Potent Antibiotics against Gram‐Positive Pathogens

In an antibiotic lead discovery program, the known strain Streptomyces armeniacus DSM19369 has been found to produce three new natural products when cultivated on a malt‐containing medium. The challenging structural elucidation of the isolated compounds was achieved by using three independent methods, that is, chemical degradation followed by NMR spectroscopy, a computer‐assisted structure prediction algorithm, and X‐ray crystallography. The compounds, named armeniaspirol A–C ( 2 – 4 ), exhibit a compact, hitherto unprecedented chlorinated spiro[4.4]non‐8‐ene scaffold. Labeling experiments with [1‐¹³C] acetate, [1,2‐¹³C2] acetate, and [U‐¹³C] proline suggest a biosynthesis through a rare two‐chain mechanism. Armeniaspirols displayed moderate to high in vitro activities against Gram‐positive pathogens such as methicillin‐resistant S. aureus (MRSA) or vancomycin resistant E. faecium (VRE). As analogue 2 was active in vivo in an MRSA sepsis model, and showed no development of resistance in a serial passaging experiment, it represents a new antibiotic lead structure.     

The interfaces of Au(111) and Au(100) in a hexaalkyl-substituted guanidinium ionic liquid: an electrochemical and in situ STM study

Five hexaalkylguanidinium-based ionic liquids have been synthesised, and based on their cyclic voltammograms the most suited one, N,N-dibutyl-N',N'-diethyl-N',N'-dimethylguanidinium bis(trifluoromethylsulfonyl)imide, has been chosen for electrochemical studies. The surface interaction of this room-temperature ionic liquid with single crystalline gold surfaces (Au(100) and Au(111)) has been investigated using cyclic voltammetry, impedance spectroscopy and in situ scanning tunnelling microscopy (STM). The interfacial capacitance was found to be very low; STM measurements revealed the hex-reconstruction and herringbone reconstruction for Au(100) and for Au(111), respectively, at negative potentials; that is, at these potentials no hints for ad-structures of the cation could be found.     

Topology of a Surface of the Phase Diagram of the Cholesteric Lyotropic Mesophase: Potassium Laurate/1-Decanol/Water/I-N-Lauroyl Potassium Alaninate

A surface of the phase diagram of the lyotropic cholesteric mesophase of potassium laurate/1-decanol/H₂O/l-N-lauroyl potassium alaninate (l-LAK) is studied by optical microscopy and X-ray diffraction as a function of the relative molar concentration of l-LAK and temperature. Cholesteric discotic and calamitic phases are observed and also a large domain of biaxial cholesteric phase. The inverse pitch as a function of the l-LAK relative molar concentration presents a linear behavior in the doping range studied. The l-LAK doping and its influence in favoring cholesteric calamitic phase formation are discussed in terms of the packing of the l-LAK amphiphile in the bilayer and the orientational fluctuations of the intrinsically biaxial correlation volumes.     

ChemInform Abstract: A Raman Spectroscopic Study of the XeOF4/XeF2 System and the X‐Ray Crystal Structure of α‐XeOF4·XeF2.

The interaction of XeF₂ with excess XeOF₄ leads to the formation of a mixture of α‐XeOF₄·XeF₂ and β‐XeOF₄·XeF₂.