Effect of number of home exercises on compliance and performance in adults over 65 years of age.

BACKGROUND AND PURPOSE: There is limited research on the effects of the number of exercises a person is told to perform on compliance and performance, as defined by cueing requirements, correct alignment, and quality of movement. Some studies of medication suggest that compliance decreases as the number of medications increases. The purpose of this study was to determine whether older adults comply and perform better (ie, requiring less cueing, exhibiting correct alignment, and exhibiting controlled, coordinated, and continuous movements) when they are asked to do 2, 5, or 8 exercises. SUBJECTS: Subjects were 11 women and 4 men, aged 67 to 82 years (X=72.8), who were living independently in their communities. METHODS: Subjects were randomly prescribed 2, 5, or 8 general strengthening home exercises. They were instructed on their exercises at an initial session and asked to record the number of repetitions performed each day in a self-report exercise log. At a return session 7 to 10 days later, subjects were scored on their performance of the prescribed exercises using a newly designed assessment tool. RESULTS: The group that was prescribed 2 exercises performed better, as defined by their performance tool score, than the group that was prescribed 8 exercises. The group that was prescribed 5 exercises was not different from the groups that performed 2 or 8 exercises. No differences were found among groups regarding the self-report measurement of compliance. There was a moderate correlation between performance scores and the self-report percentage rates. CONCLUSION AND DISCUSSION: Subjects who were prescribed 2 exercises performed better than subjects who were prescribed 8 exercises. The question of an optimal number of exercises to prescribe to elderly people warrants further study.

High-resolution tandem mass spectrometry of large biomolecules.

Unit-resolution mass spectra have been obtained for peptides as large as 17 kDa, providing information on impurities and adduct ions, as well as accurate molecular weight values. Electrospray ionization produces many multiply-charged species of the same mass; isotopic peak resolution provides direct charge state assignment from the unit mass spacing of the isotopes. This is of special value when the spectrum also has many masses, such as from precursor ion dissociation or impurities. Mass measuring errors not only are concomitantly lower (less than 0.1 Da) than when the isotopic peaks are unresolved but also are independent of variations in 13C/12C natural isotopic abundances. Also, larger errors are avoided that occur when the measured peak envelope includes impurity or adduct ions. This also benefits tandem mass spectrometry; dissociation of peptide ions as large as 8.5 kDa yields fragment masses consistent (less than 0.1 Da) with their amino acid sequences.

Surface-induced dissociation of peptide ions in Fourier-transform mass spectrometry.

Peptide molecular ion species up to m/z 3055 introduced into a Fourier-transform mass spectrometer can be made to undergo extensive fragmentation by electrically floating the ion cell. The proportion of ions dissociated increases with increasing voltage, with 48 eV producing the highest absolute abundance of fragment ions above m/z 200. At this energy, spectra closely resemble those from photodissociation at 193 nm, indicating an internal energy deposition of 6-7 eV; change of product abundances with kinetic energy resembles a conventional breakdown curve. The precursor ions apparently are electrostatically attracted to strike screen wires across the ion cell entrance, producing daughter ions of low kinetic energy.

Fourier-transform mass spectrometry of large molecules by electrospray ionization.

The multiply charged ions produced by electrospray ionization of peptides of molecular masses up to 29 kDa have been successfully introduced into a Fourier transform mass spectrometer of unique capabilities for tandem mass spectrometry, large ion dissociation, and resolution. Electrospray ionization places an unusually high number of charges on a peptide yielding mass/charge (m/z) values of 600-1500; in this range at normal operating pressures (approximately 10(-9) torr; 1 torr = 133.3 Pa) Fourier-transform mass spectrometry resolving power is greater than 100,000. Although only 10(-7) torr pressure has been obtained with the initial interface, the resulting resolving power of 5000 makes possible the resolution of isotopic peaks of multiply charged ions. Mass measuring accuracies of a few daltons for molecular masses up to 17 kDa have also been achieved.

The detection and estimation of (A) arsenic in opium, and (B) strychnine in opium and heroin, as a means of identification of their respective sources.

Samples of opium with arsenic as an adulterant, and both opium and heroin with strychnine as an adulterant are not infrequently encountered in the local drug scene. The paper describes a method for the possible identification of the sources of opium and heroin in the local market on the basis of an accurate quantitation of the adulterant arsenic and strychnine contents of the respective samples. A possible extension of this concept, would be the possibility of a similar identification of sources outside the country with a view to establishing channels of entry from abroad. Arsenic is determined by the Gutzeit method while strychnine is estimated by high performance liquid chromatography (HPLC).