Evaluating helicopter emergency medical missions: a reliability study of the HEMS benefit and NACA scores.

Background: The benefits of the Helicopter Emergency Medical Service (HEMS) and dispatch accuracy are continuously debated, and a widely accepted score to measure the benefits of the mission is lacking. The HEMS Benefit Score (HBS) has been used in Finnish helicopter emergency medical services, but studies are lacking. The National Advisory Committee for Aeronautics (NACA) score is widely used to measure the severity of illness or injury in the pre-hospital setting, but it has many critics due to its subjectivity.

Stereocontrolled synthesis of spiroketals via Ti(Oi-Pr)4-mediated kinetic spirocyclization of glycal epoxides with retention of configuration.

A Ti(Oi-Pr)4-mediated kinetic spiroketalization reaction has been developed for the stereocontrolled target- and diversity-oriented synthesis of spiroketals. In contrast to most existing methods for spiroketal synthesis, this reaction does not rely upon thermodynamic control over the stereochemical configuration at the anomeric carbon. Stereochemically diverse glycals are first alkylated at the C1-position to introduce a hydroxyl-bearing side chain, then epoxidized stereoselectively.

Stereocontrolled synthesis of spiroketals via a remarkable methanol-induced kinetic spirocyclization reaction.

A methanol-induced kinetic spiroketalization reaction has been developed for the stereocontrolled target- and diversity-oriented synthesis of spiroketals. In contrast to existing methods for spiroketal synthesis, this reaction does not depend on thermodynamic product stability or require axial attack of an oxygen nucleophile. Stereodiverse glycals are alkylated at the C1 position with side chains bearing protected hydroxyl groups.

Enantioselective synthesis of erythro-4-deoxyglycals as scaffolds for target- and diversity-oriented synthesis: new insights into glycal reactivity.

An efficient, enantioselective synthesis of erythro-4-deoxyglycals has been developed using asymmetric aldehyde allylation and tungsten-catalyzed alkynol endo-cycloisomerization as the key steps. These versatile synthetic scaffolds have been elaborated to a variety of products using stereoselective transformations that are complementary to those available using the corresponding threo glycals. This work has provided valuable insights into the relationships between glycal structure and reactivity.

In vitro stability of alpha-helical peptide nucleic acids (alphaPNAs).

Alpha-helical peptide nucleic acids (alphaPNAs) are synthetic molecules that merge the alpha-helix secondary structure of peptides with the codified Watson-Crick base pairing capability of nucleic acids. It is now demonstrated that alphaPNAs made up of either L- or D-amino acids are resistant to degradation by the proteases present in human serum. The increased stability of alphaPNAs towards proteases may be attributable to the presence of unnatural nucleoamino acid residues [-NHCH(CH(2)OCH(2)B)CO-, where B=thymine or cytosine] since the replacement of these amino acids by serine yields a control peptide that does break down in human serum.