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E Fosslien

Publications and source records attributed to E Fosslien.

24 records · Page 2Linked to original sources
PubMed1970

Automatic lipid extraction and thin-layer chromatography application with a prgrammed flow system.

An eight-channel programmed flow system for automatic lipid extraction and TLC application is described. Each channel has a container for lipid extraction connected by Acidflex tubing through an AutoAnalyzer pump to a TLC applicator needle. Extraction containers are prepared from disposable Oxford sampler pipet tips by inserting a small cotton filter into their lower, narrower end, which is connected to the pump tubing. The applicator needles are supported vertically in a manifold, and their tips rest on a TLC plate placed on a hot plate. Serum is added to isopropanol in each extraction container, and proteins are completely precipitated in 2 min and retained in the extraction chambers by the cotton filters; lipid extracts are then transferred on to the heated TLC plate by intermittent pumping at a rate allowing for continuous evaporation of isopropanol under streams of warmed air or nitrogen. The lipids accumulate on the plate in eight small spots, one for each channel. Solvent is proportionally added into the extraction chambers from a common reservoir through Acidflex tubing in a second AutoAnalyzer pump. During the extraction procedure, both pump motors are automatically operated by a programmed timer with a solid-state switch. Of several different solvents tested, isopropanol is the fastest for protein precipitation and lipid extraction and does not extract substances from the Acidflex tubing which interfere with chromatographic separation.

1-Propanol↗
PubMedDate not supplied

Improved immunodiagnosis of neutrophil dysfunction in the newborn and infant.

An improved assay for the simultaneous assessment of phagocytic uptake (via Immunobeads) and metabolic integrity (via nitroblue tetrazolium (NBT) dye reduction) was used to evaluate the neutrophil function in neonates, one year olds, and adults. The unique advantage of this assay is that it offers greater standardization since the beads are commercially available with a known quantity of immunoglobulin bound to their surface which allows for considerably less variation than particles opsonized in vivo. Blood samples were collected from 20 full term healthy neonates, 20 healthy one year olds, and 20 healthy adults. The neutrophils were isolated, and phagocytic and killing function compared among the three groups. It was found that the neonates had a small but significant neutrophil dysfunction with respect to phagocytic and intracellular killing ability when compared to the one year olds and adults. Additionally, blood was collected and evaluated from five premature infants with varying degrees of stress. Their neutrophil dysfunction was much more pronounced. Although it was previously thought that full term healthy neonates have no demonstrable neutrophil dysfunction unless stressed in some manner, a subtle dysfunction was identified even in unstressed neonates. It was, however, found to be more pronounced if the neonate was either premature or stressed in some manner. It is hoped that this assay, through its greater sensitivity and ease of standardization, will uncover subtle neutrophil dysfunctions in various disease states that as yet remain undiagnosed. The clinical significance of such subtle neutrophil dysfunctions is not yet known.

Adolescent↗
PubMedDate not supplied

Adverse effects of nonsteroidal anti-inflammatory drugs on the gastrointestinal system.

Two enzymes, cyclo-oxygenase (COX) and 5-lipoxygenase, act upon arachidonic acids to produce prostaglandins and leukotrienes. Inhibition of COX-2 by non-steroidal anti-inflammatory drugs (NSAIDs) lowers synthesis of proinflammatory prostaglandins and produces analgesia. COX-2 is highly inducible by endotoxin, IL-1, hypoxia, epidermal growth factor (EGF), benzo[a]pyrene, and transforming growth factor beta 1(TGF-beta 1). COX-1 in constitutively expressed. Conventional NSAIDs also inhibit the synthesis of cytoprotective prostaglandins by COX-1 in the gastrointestinal tract. Surplus arachidonic acids accumulate and enhance the generation of leukotrienes via the lipoxygenase pathway inducing neutrophil adhesion to endothelium and vasoconstriction. The NSAIDs harboring a carboxyl group also inhibit oxidative phosphorylation (OXPHOS) lowering adenosine-triphosphate (ATP) generation leading to loss of mucosal cell tight junctions and increased mucosal permeability. Administration of NSAIDs that do not interfere with OXPHOS, and concomitant use of prostaglandin analogues to restore cytoprotection reduces complications of NSAID use. However, no NSAID that lacks potential for serious gastrointestinal toxicity is currently available. Selective inhibitors of COX-2 and 5-lipoxygenase are newer, promising drugs. Surprisingly, COX-2 null mice are able to mount an inflammatory response, suffering however, from kidney dysfunction and a shortened life span. Results of clinical studies on the long-term use of NSAID drugs such as selective inhibitors are still pending.

Aging↗