The use of biomarkers to describe plasma-, red cell-, and blood volume from a simple blood test.

Plasma volume and red cell mass are key health markers used to monitor numerous disease states, such as heart failure, kidney disease, or sepsis. Nevertheless, there is currently no practically applicable method to easily measure absolute plasma or red cell volumes in a clinical setting. Here, a novel marker for plasma volume and red cell mass was developed through analysis of the observed variability caused by plasma volume shifts in common biochemical measures, selected based on their propensity to present with low variations over time. Once a month for 6 months, serum and whole blood samples were collected from 33 active males. Concurrently, the CO-rebreathing method was applied to determine target levels of hemoglobin mass (HbM) and blood volumes. The variability of 18 common chemistry markers and 27 Full Blood Count variables was investigated and matched to the observed plasma volume variation. After the removal of between-subject variations using a Bayesian model, multivariate analysis identified two sets of 8 and 15 biomarkers explaining 68% and 69% of plasma volume variance, respectively. The final multiparametric model contains a weighting function to allow for isolated abnormalities in single biomarkers. This proof-of-concept investigation describes a novel approach to estimate absolute vascular volumes, with a simple blood test. Despite the physiological instability of critically ill patients, it is hypothesized the model, with its multiparametric approach and weighting function, maintains the capacity to describe vascular volumes. This model has potential to transform volume management in clinical settings. Am. J. Hematol. 92:62-67, 2017. © 2016 Wiley Periodicals, Inc.

Oral bovine colostrum supplementation enhances buffer capacity but not rowing performance in elite female rowers.

A randomized, double-blind, placebo controlled design was used in which 13 elite female rowers, all of whom had competed at World Championships, were supplemented with 60 g day-1 of either bovine colostrum (BC; n = 6) or concentrated whey protein powder (WP; n = 7) during 9 weeks of pre-competition training. All subjects undertook the study as a group and completed the same training program. Prior to, and after 9 weeks of supplementation and training, subjects completed an incremental rowing test (ROW1) on a rowing ergometer consisting of 3 3 4-min submaximal workloads and a 4-min maximal effort (4 max), each separated by a 1-min recovery period. The rowing test was repeated after a 15-min period of passive recovery (ROW2). The 4 max for ROW1 provided a measure of performance, and the difference between the 4 max efforts of ROW1 and ROW2 provided an index of recovery. Blood lactate concentrations and pH measured prior to exercise and at the end of each workload were used to estimate blood buffer capacity (beta). Food intake was recorded daily for dietary analysis. There were no differences in macronutrient intakes (p >.56) or training volumes (p >.99) between BC and WP during the study period. Rowing performance (distance rowed and work done) during 4 max of ROW2 was less than ROW1 at baseline (p <.05) but not different between groups (p >.05). Performance increased in both rows by Week 9 (p <.001), with no difference between groups (p >.75). However, the increase was greatest in ROW2 (p <.05), such that by Week 9 there was no longer a difference in performance between the two rows in either group (p >.05). b was not different between groups for ROW1 at baseline (BC 38.3 5.0, WP 38.2 7.2 slykes; p >.05) but was higher in BC by Week 9 (BC 40.8 5.9, WP 33.4 5.3 slykes; p <.05). b for ROW2 followed the same pattern of change as for ROW1. We conclude that supplementation with BC improves b, but not performance, in elite female rowers. It was not possible to determine whether b had any effect on recovery.