Economic aspects of the prolonged fluoride application method

A bstract — Cost-benefit and cost-effectiveness analyses were carried out to obtain an indication of the economic viability of the prolonged fluoride application (PFA) method. Using three year results from a clinical trial of the technique, the cost-benefit ratio was calculated as 1:2.1 and the cost-effectiveness as $3.49 per surface saved in three years. For purposes of general comparison the same analyses were made for an alternative measure, the placement of pit and fissure sealants. Using data from a two-year sealant trial, the cost-benefit ratio was found to be 1:0.77 and the cost-effectiveness $18.49 per surface saved in two years. The findings indicated that the PFA method can be regarded as an economically viable procedure.     

Radioimmunoassay of CSF for encephalitogenic basic protein: a diagnostic test for MS?

Competitive inhibition of binding between radioiodine-labelled encephalitogenic basic protein from human myelin (¹²⁵I-HEProt) and normal human alpha-2 macroglobulin and between ¹²⁵I-HEProt and rabbit antiHEProt serum was used to study concentrated cerebrospinal fluid (CSF) under “blind” control for cross-reactivity with HEProt. Samples of CSF from patients meeting the standard criteria for definite MS and possible MS, and from patients with optic neuritis and “other” diagnoses were studied. CSF from patients in all four groups was shown to have an inhibitor cross-reactive with HEProt when studied by the ¹²⁵I-HEProt/alpha-2 macroglobulin test, but the amount was significantly greater in the definite MS group than in the “other” group. Results of the two tests on CSF from MS patients correlated, suggesting that the tests were identifying the same inhibitor. It was concluded that CSF contains an inhibitor similar to HEProt and that the amount present in CSF could be a useful diagnostic marker of MS.     

Evidence for a directional correspondence between eye movements and dream imagery in REM sleep

We examined the relationship between eye movement direction in REM sleep recorded by electrooculograph (EOG) and gaze direction in dream imagery. In a double-blind protocol, carefully screened and trained subjects were awakened subsequent to direct coupled EOG activity that was either predominantly horizontal or vertical. Following a target eye movement that fulfilled predetermined amplitude and directional criteria, a brief period of ocular quiescence was allowed to transpire before the subject was awakened. The dream narratives and EOG activity occurring prior to the REM awakenings were each reduced to a series of quantitatively scaled ratings. Analyses of variance demonstrated that when the confidence level of the experimenters' prediction is taken into account, statistically significant relationships exist between the number and direction of shifts of gaze in the dream report and scaled measurements of the corresponding EOG. When given dream narratives and the corresponding EOG recordings in sets of four, judges were unable to match them correctly better than by chance. However, in the above matching, judges significantly paired the dream narratives with EOG recordings that were in the same axis of gaze.     

Meroterpenes from the ascidian Aplidium aff. densum

Chemical investigation of the ascidian Aplidium aff. densum collected at Masirah Island, Oman, has resulted in the isolation of five meroterpenes: two new ones, methoxyconidiol (1) and didehydroconicol (2), and three related, known compounds, 3-5. The structures of 1 and 2 were determined by a combination of mass spectrometry and one- and two-dimensional high-field NMR techniques. Their biological activities against bacteria and human lymphoblastic cell lines were evaluated.     

Primes and targets in rapid chases: tracing sequential waves of motor activation

Single-cell recordings have indicated that visual stimuli elicit rapid waves of neuronal activation that propagate so fast that they might be free of intracortical feedback. Here, the time course of feedforward activation was traced by measuring pointing responses to color targets preceded by color primes initiating either the same or opposite response. The early time course of priming effects was strictly time locked to prime onset and depended only on properties of the primes, but was independent of the onset times of the actual targets as well as the perceptual effects of targets on primes. Results indicated that nonoverlapping feedforward signals by primes and targets traverse the visuomotor system in a rapid chase, controlling associated motor responses in strict sequence.