Our data confirm that both FFM and FM are significant contributors to BMR. When the effect of FM on BMR is removed, any association with leptin concentrations disappears, which suggests that previous links between circulating leptin concentrations and BMR occurred only because of inadequate control for the effects of FM.

In the short term, high-protein, low-carbohydrate ketogenic diets reduce hunger and lower food intake significantly more than do high-protein, medium-carbohydrate nonketogenic diets.

Background:The most commonly used predictive equation for basal metabolic rate (BMR) is the Schofield equation, which only uses information on body weight, age and sex to derive the prediction. However, because body composition is a key influencing factor, there will be error in calculating an individual's basal requirements based on this prediction. Objective: To investigate whether adding additional anthropometric measures to the standard measures can enhance the predictability of BMR and to cross-validate this within a separate subgroup. Design: Cross-sectional study of 150 Caucasian adults from Scotland, with a body mass index range of 16.7-49.3 kg/m 2 . All subjects underwent measurement of BMR, body composition, and 148 also had basic skinfold and circumference measures taken. The resultant equation was tested in a subgroup of 39 obese males. Results: The average difference between the predicted (Schofield equation) and measured BMR was 502 kJ/day. There was a slight systematic bias in this error, with the Schofield equation underestimating the lowest values. The average discrepancy between predicted and actual BMR was reduced to 452 kJ/day, with the addition of fat mass, fat-free mass, an overall 10% improvement on the Schofield equation (P ¼ 0.054). Using an equation derived from principal components analysis of anthropometry measurements similarly decreased the difference to 458 kJ/day (P ¼ 0.039). Testing the equation in a separate group indicated a 33% improvement in predictability of BMR, compared to the Schofield equation. Conclusions: In the absence of detailed information on body composition, utilizing anthropometric data provides a useful alternative methodology to improve the predictability of BMR beyond that achieved from the standard Schofield prediction equation. This should be confirmed in more individuals, both within the obese and normal weight category.

The consequences of selection for shorter, stiffer-strawed varieties that are less susceptible to lodging on the degradability of forage and straw obtained from cereal crops were investigated with particular reference to the characteristics of the basal internode where the mechanical stress is likely to be greatest. Quantitative measurements of tissue area, mean cell wall thickness, cell wall density and cell size were made on two wheat cultivars, Riband (strong) and Norman (weak), and on two barley cultivars, Blenheim (strong) and Tyne (weak). The cultivars were selected for comparison on the basis of their straw strength in field trials.At growth stage (GS) 59 in wheat (ear emergence complete) the neutral detergent fibre (NDF) content of the basal internode of Riband (74-6%) was lower than Norman (86-0%), and the NDF degradability (NDFD) of Riband (34-7%) was slightly greater than Norman (320%). No significant differences in lignin content were found between the wheat cultivars. In barley at the same growth stage, the NDF content of the basal internode of Blenheim (84-8%) was lower than Tyne (89-2%), and the NDFD of Blenheim (30-2%) was greater than Tyne (23-7%) but no significant differences in lignin content were associated with the difference in NDFD. At GS 32-37 (stem elongation) in barley the NDF content of the basal internode of Blenheim (81-5%) was also lower than Tyne (86-3 %), but the NDFD of Blenheim (71-7%) was much greater than Tyne (42-8%). No significant differences in lignin content were associated with this large difference in NDFD.The cultivars of wheat and barley less susceptible to lodging showed lower NDF content and higher in vitro degradability in the basal internode than the more susceptible cultivars. No evidence of differences in the extent of cross-linking by ether-bound ferulic acid was found in wheat, but stems of Blenheim barley showed evidence of a greater degree of cross-linking than in Tyne. The anatomical features of Norman wheat were consistent with stem weakness caused by thinner, smaller cells than the stronger Riband. However, in contrast, the anatomy of Tyne barley indicated that the straw may be too stiff, resulting in failure due to root lodging or brackling while the thinner more cross-linked cell walls of Blenheim may allow the stem to bend under load.The relationship between the anatomical features, chemical composition and in vitro degradability of the stems was investigated using stepwise multiple regression. Thickness of sclerenchyma, thickness of epidermis and density of epidermis (area fraction of cell wall) were selected by the method of 'backward elimination' from an initial regression model to predict NDFD using all the anatomical features measured. Thickness of sclerenchyma was ranked first when the selected anatomical features were incorporated into a regression model with NDF and lignin content using the method of' forward selection'. Anatomical differences between varieties had an effect on degradability distinct from that due to the overall chemical compos...

Parenchyma and sclerenchyma cell walls were mechanically isolated from sections of a newly extended maize internode containing cells at different stages of maturity. Internodes were divided into four equal segments (A[top]-D[bottom)) and preparations of both cell types obtained from each segment. The lignin content ofsclerenchyma (57'5-108·3 g kg-I) was greater than that of parenchyma (48·0-86'8 g kg"") at all stages of development. The extent oflignification increased with age in both cell types but was similar in cells taken from segments A and B. The ratio of the saponifiable phenolic acids differed with age with levels of (E +Z)-ferulic acid remaining essentially constant while the (E +Z)-p-coumaric acid content increased in parallel with lignification. The extent to which commercial 'cellulase' was able to degrade both cell types decreased with age and extent oflignification. Sclerenchyma walls were less degradable than parenchyma walls isolated from the same segment. The fitted rate constant calculated for the period 2-72 h, however, was independent of both age and cell type. The mean thickness of sclerenchyma walls increased with age because of secondary wall formation (confirmed by image analysis of sections prepared for microscopy) while parenchyma remained thin walled. The consequences oflignification appeared to be essentially the same for both cell types and, by implication, for both primary and secondary wall layers.