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OBJECTIVES: Hexavalent chromium (Cr(VI)) is classified as a human carcinogen. Occupational Cr(VI) exposure can occur during different work processes, but the current exposure to Cr(VI) at Swedish workplaces is unknown.METHODS: This cross-sectional study (SafeChrom) recruited non-smoking men and women from 14 companies with potential Cr(VI) exposure (n = 113) and controls from 6 companies without C

Ventral midbrain dopaminergic neurons project to the striatum as well as the cortex and are involved in movement control and reward-related cognition. In Parkinson's disease, nigrostriatal midbrain dopaminergic neurons degenerate and cause typical Parkinson's disease motor-related impairments, while the dysfunction of mesocorticolimbic midbrain dopaminergic neurons is implicated in addiction and n

Kan du som sociolog bli "bättre" på att teoretisera och i så fall hur? Handlar det om att behärska vissa vetenskapliga metoder för teoretiserande eller tvärtom om att släppa loss och inte tänka så mycket på vad du gör och varför? Är det det ena eller det andra som gäller, eller ska du snarare växla mellan olika förhållningssätt? Måste kreativiteten frigöras och i så fall från vad? I denna korta te

Crystallographic data for 620 C - nitro-O⋯H - N,O hydrogen bonds, involving 560 unique H atoms, have been investigated to the van der Waals limit of 2.62 Å. The overall mean nitro-O⋯H bond length is 2.30 (1) Å, which is much longer (weaker) than comparable hydrogen bonds involving >C=O acceptors in ketones, carboxylic acids and amides. The donor hydrogen prefers to approach the nitro-O atoms in th

The double nucleation mechanism of amyloid β (Aβ) peptide aggregation is retained from buffer to cerebrospinal fluid (CSF) but with reduced rate of all microscopic processes. Here, we used a bottom-up approach to identify retarding factors in CSF. We investigated the Aβ42 fibril formation as a function of time in the absence and presence of apolipoprotein A-I (ApoA-I), recombinant high-density lip

The barrier function of the skin is mainly assured by its outermost layer, stratum corneum (SC). One key aspect in predicting dermal drug delivery and in safety assessment of skin exposure to chemicals is the need to determine the amount of chemical that is taken up into the SC. We here present a strategy that allows for direct measures of the amount of various solid chemicals that can be dissolve

Parkinson's disease is characterized by the aggregation of the presynaptic protein α-synuclein (αSyn), and its co-assembly with lipids and other cellular matter in the brain. Here we investigated lipid-protein co-assembly in a system composed of αSyn and model membranes containing the glycolipid ganglioside GM3. We quantified the uptake of lipids into the co-assembled aggregates and investigated h

Films of poly-L-leucine, poly-L-valine, and poly-L-isoleucine have been studied at the air-water interface by surface balance experiments. In addition, Langmuir-Blodgett (LB) films of these polypeptides deposited onto quartz and mica have been studied by circular dichroism (CD) spectroscopy and atomic force microscopy (AFM) to elucidate the effects of polypeptide conformation and spreading agent (

The outer part of the skin, stratum corneum, is essential to the skin's barrier function. Monolayer and bulk phase behavior of stratum corneum model lipids have thus been studied. Domain formation in Langmuir-Blodgett monolayers of synthetic ceramides (C16CerIII and C24CerIII), cholesterol, and free fatty acids (lignoceric acid, C24:0, and palmitic acid, C16:0) were investigated by atomic force mi

Osmotic forces are important in regulating a number of physiological membrane processes. The effect of osmotic pressure on lipid phase behavior is of utmost importance for the extracellular lipids in stratum corneum (the outer part of human skin), due to the large gradient in water chemical potential between the water-rich tissue on the inside, and the relative dry environment on the outside of th

The outer part of the skin, stratum corneum, has an architecture of keratin filled cells, the corneocytes, embedded in stacked lipid bilayers. The lamellar structure provides an effective barrier to passive diffusion of small molecules and prevents uncontrolled water loss. In this paper, we present a theoretical model for molecular diffusional transport over an oriented stack of liquid crystalline

Very small rectangular domains were observed by atomic force microscopy in binary monolayers of synthetic ceramides and cholesterol. When the cholesterol content is increased the domains are bigger although the rectangular shape is retained. The almost perfect shape of the domains indicates two-dimensional single ceramide crystals. Lipid domains in monolayers of this particular shape and size have

This contribution summarises the results from a number of investigations undertaken in the spirit of the Domain Mosaic Model proposed by Forslind in 1994. Atomic Force Microscopy (AFM) studies on the two-dimensional phase behaviour of some stratum corneum lipids revealed phase separation of the lipids in the typical case and the ability of cholesterol to reduce the line tension between phases. A t

The complex 12+ which has two pendant 4-pyridyl substituents may be viewed as a metal-containing analogue of 4,4′-bipyridine. The complex undergoes N-alkylation reactions with a variety of alkylating agents to give more highly functionalised tetracationic complexes which may be termed metalloviologens by analogy with viologens. These complexes may also be prepared by alkylation of the free ligands

The reaction of [Os3H2(CO)10] with Me3SiC2C2SiMe3 affords both [Os3(μ-H) (CO)10{μ-η1-η2-HC 2(SiMe3)C2(SiMe3)}] (1) and [Os3(μ-CO)(CO)9(μ3-η 2-Me3SiC2C2SiMe3)] (2) in good yield, 2 being favoured with an excess of diyne. In 1, one edge of the triosmium unit is bridged by the vinyl moiety of a transformed bis(trimethylsilyl)-1,4-butadiyne ligand that has undergone a hydride transfer and a 1,2-trimet

In this study the effect of cholesterol in Langmuir-Blodgett monolayers of fatty acids of varying chain lengths was investigated by atomic force microscopy (AFM). Domain formation due to lateral phase separation was studied at different lipid compositions and surface pressures. A small amount of cholesterol is miscible with palmitic acid (C16:0) and forms a flat monolayer while excess cholesterol

Monolayers of palmitic (C16:0) and lignoceric acid (C24:0) and their equimolar mixture were transferred to a hydrophilic mica substrate at various surface pressures and investigated by means of atomic force microscopy (AFM) in contact and lateral force modes. The first-order transition of lignoceric acid gives a plateau region, representing a liquid expanded to liquid condensed phase transition in