Multivariate Meta-Analysis of Brain-Mass Correlations in Eutherian Mammals.

The general assumption that brain size differences are an adequate proxy for subtler differences in brain organization turned neurobiologists toward the question why some groups of mammals such as primates, elephants, and whales have such remarkably large brains. In this meta-analysis, an extensive sample of eutherian mammals (115 species distributed in 14 orders) provided data about several different biological traits and measures of brain size such as absolute brain mass (AB), relative brain mass (RB; quotient from AB and body mass), and encephalization quotient (EQ). These data were analyzed by established multivariate statistics without taking specific phylogenetic information into account.

Investigation of the aluminium biokinetics in humans: a 26Al tracer study.

Despite the well-known toxicity of aluminium in chronic renal failure, a solid database on its biokinetics has been difficult to establish. A highly sensitive method using (26)Al as tracer and accelerator mass spectrometry (AMS) for detection was used. No perturbing background and saturation effects were taken into account using a delta function input of aluminium in time.

Compartmental model for aluminium biokinetics.

An open compartmental model for describing aluminium biokinetics is presented with a central compartment consisting of transferrin- and citrate-bound aluminium in blood plasma and interstitial fluid, and three peripheral compartments for organs, muscles and bones and the gastro-intestinal tract. The rate constants describing the transport of aluminium are normalized to an estimated plasma volume and do not depend on the size of the individual. Effects due to changes in compartmental sizes or to transport characteristics are described.

Ultrasensitive analysis of the intestinal absorption and compartmentalization of aluminium in uraemic rats: a 26Al tracer study employing accelerator mass spectrometry.

Background: Developments in accelerator mass spectrometry (AMS) now permit the determination of femtogram amounts of 26Al in blood and in various tissues with good precision and free of external contamination.

Methods: In the present study we used trace quantities of 26Al to investigate the intestinal absorption and compartmentalization of aluminium in rats with renal failure (Nx, 5/6 nephrectomy) and in pair-fed controls (C). Single oral doses of 20 ng 26Al were administered to six animals in each group and, subsequently, 24-h post-load 26Al was analysed in serum, urine, bone, liver, and spleen by means of AMS.