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To the Editor: We describe cowpox with corneal involvement in a 31-year-old atopic woman who lived in southern Finland and was unvaccinated for smallpox. In August 2009, she noticed irritation [...]

An investigation whether phospholipid transfer protein (PLTP) and cholesteryl ester transfer protein (CETP) are present in human tear fluid is conducted, in order to gain insight into the formation of tear film. The results suggest that PLTP may play role in the formation of the tear film by supporting phospholipid transfer.

The distribution, orientation, and dynamics of 1,6-diphenyl-1,3,5-hexatriene (DPH) fluorescence probes in a dipalmitoylphosphatidylcholine (DPPC) bilayer were studied using 50 ns molecular dynamics. The results indicated that DPH did not prefer to be embedded in the membrane center where free volume was largest.

A novel approach is described, which studies enzymatic reactions and allows manipulating giant vesicles as well as cultured cells in a spatially controlled manner. The study shows that the enzymatic catalysis can be restrained topically to the site of contact between the vesicle and the derivatized microsphere.

The physicochemical properties of sphingolipids in a 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC) matrix were investigated. To this end, the behaviors of two chemically well-defined sphingolipids, N-palmitoyl-sphingomyelin and the corresponding ceramide, were compared. Experimental results showed that the enzymatic generation of ceramide from sphingomyelin stimulates microdomain formation in LUVs, although the reorganization of ceramide into microdomains within the bilayer took a significantly longer time.

A synthetic peptide, corresponding to 1 to 42 amino acid residue of amyloid beta-peptide (A-Beta(sub 1-42)), enhances the hydrolysis of the pyrene-labeled acidic phospholipid analog 1-palmitoyl-2-((pyren-1-yl))hexanoyl-sn-glycero-3-phosphoglycerol by porcine pancreatic phospholipase A(sub 2). Ca2+, at higher concentrations, abolishes the enhancing effect of A-Beta(sub 1-42), which is found in senile plaques in Alzheimer's disease (AD). Brain samples of AD patients show decreased levels of phosphatidylcholine. Activation of lipolytic enzyme by amyloid beta peptide indicates a direct involvement of the peptide in neuronal cell death in AD afflicted brain tissue.

Biochemical studies are conducted to identify proteins in retinal cell extracts that interact with RP2 in order to define the role of RP2 in the retina and X-linked retinitis pigmentosa (XLRP). The studies have shown that RP2, in addition to serving as a regulator of ADP ribosylation factor-like 3 (Arl3), has interacted with N-ethylmaleimide sensitive factor (NSF) and the complex has played a vital role in membrane protein trafficking in photoreceptors and other cells of the retina.

The interfacial properties of phospholipid transfer protein (PLTP) are studied using Langmuir phospholipid monolayers and asymmetrical flow field--flow fractionation (AsFIFFF) to follow the transfer of [super 14]C-labeled phospholipids and {[super 35]S}PLTP between lipid vesicles and high-density lipoprotein particles. It is observed that high activity-PLTP (HA-PLTP) can transfer lipids by a shuttle mechanism and phospholipid transfer can take place in the absence of formation of ternary complex between PLTP, acceptor and donor particles.

The influence of pyrene-labeled phospholipids on the structural properties of a fluid dipalmitoylphosphatidylcholine lipid membrane is elucidated. The pyrene labeling is found to perturb the membrane structure significantly in the vicinity of the probe, the correlation length in the bilayer plane being about 1.0-1.5 nm.

The structural dynamics of the main phase transition of large unilamellar dipalmitoylphosphocholine (DPPC) vesicles were studied using differential scanning calorimetry (DSC) with steady-state and time-resolved fluorescence spectroscopy. It indicates the possibility that there is an intermediate phase of strongly fluctuating lattice of fluidlike and gel-like lipids.