Peptides from the Site of Chicken Anti-DNP Antibodies

Hapten binding sites of chicken anti-DNP antibody appear to contain an iodinatable residue since their binding activity is decreased by iodi-nation of the antibody. The presence of the hapten -DNP-lysine during iodination protects the site. Peptides were isolated from peptic digests of the pair-iodinated antibody which appear to have come from the binding site.     

Can greater muscularity in larger individuals resolve the 3/4 power-law controversy when modelling maximum oxygen uptake?

Background:?The power function relationship, MR?=?a·m^b, between metabolic rate (MR) and body mass m has been the source of much controversy amongst biologists for many years. Various studies have reported mass exponents (b) greater than the anticipated ‘surface-area’ exponent 0.67, often closer to 0.75 originally identified by Kleiber.

Aim:?The study aimed to provide a biological explanation for these ‘inflated’ exponents when modelling maximum oxygen uptake (?max), based on the observations from this and previous studies that larger individuals develop disproportionately more muscle mass in the arms and legs.

Research design and subjects:?A cross-sectional study of 119 professional soccer players from Croatia aged 18–34 was carried out.

Results:?Here we confirm that the power function relationship between ?max and body mass of the professional soccer players results in an ‘inflated’ mass exponent of 0.75 (95% confidence interval from 0.56 to 0.93), but also the larger soccer players have disproportionately greater leg muscle girths. When the analysis was repeated incorporating the calf and thigh muscle girths rather than body mass as predictor variables, the analysis not only explained significantly more of the variance in ?max, but the sum of the exponents confirmed a surface-area law.

Conclusions:?These findings confirm the pitfalls of fitting body-mass power laws and suggest using muscle-girth methodology as a more appropriate way to scale or normalize metabolic variables such as ?max for individuals of different body sizes.     

Tai Chi Chuan Increases Circulating Myeloid Dendritic Cells

Dendritic cells, the most potent antigen-presenting cells linking innate and adoptive immunity, are thought to be important targets of immune modulators such as exercise. We examined the effect of Tai Chi Chuan (TCC) on dendritic cells. TCC practitioners were further divided to high-level practitioners (TCC-H) and low-level practitioners (TCC-L). The quantities of myeloid and plasmacytoid dendritic cells were estimated by flow cytometry. We examined parameters including age, body weight, body length, body fat, and serum albumin level, in the controls, TCC-H and TCC-L, which did not differ significantly. The mean peak (volume of O₂ utilization) of the TCC-H group was greater than that of the sedentary control group. White blood cell (WBC) count in the entire TCC group was greater than that of the controls. The quantity of myeloid dendritic cells was significantly greater in the TCC group, whereas the quantity of plasmacytoid dendritic cells was similar for both groups. Among the TCC subgroups, the quantity of myeloid dendritic cells, but not plasmacytoid dendritic cells, in the TCC-H group was greater than that of TCC-L practitioners. TCC could increase the number of circulating myeloid dendritic cells, but not plasmacytoid dendritic cells, in a performance level-dependent manner.