Precision rehabilitation: optimizing function, adding value to health care

Precision medicine efforts are underway in many medical disciplines; however, the power of precision rehabilitation has not yet been explored. Precision medicine aims to deliver the right intervention, at the right time, in the right setting, for the right person, ultimately, bolstering the value of the care that we provide. To date precision medicine efforts have rarely focused on function at the level of a person, but precision rehabilitation is poised to change this and bring the focus on function to the broader precision medicine enterprise. To do this, subgroups of individuals must be identified based on their level of function via precise measurement of their abilities in the physical, cognitive, and psychosocial domains. Adoption of electronic health records, advances in data storage and analytics, and improved measurement technology make this shift possible. Here we detail critical components of the precision rehabilitation framework, including 1) the synergistic use of various study designs, 2) the need for standardized functional measurements, 3) the importance of precise and longitudinal measures of function, 4) the utility of comprehensive databases, 5) the importance of predictive analyses, and 6) the need for system and team science. Precision rehabilitation has the potential to revolutionize clinical care, optimize function for all individuals, and magnify the value of rehabilitation in healthcare; however, to reap the benefits of precision rehabilitation, the rehabilitation community must actively pursue this shift.

Using the critical body residue approach to determine the acute toxicity of cadmium at varying levels of water hardness and dissolved organic carbon concentrations

The linkage between acute adverse effects of cadmium and internal cadmium levels were investigated for the oligochaete worm Lumbriculus variegatus in water at varying degrees of hardness and two different dissolved organic carbon (DOC) concentrations. The LC₅₀s for the effect of cadmium on the survival of the worms greatly differed depending on water hardness and DOC. We found less variability in internal metal toxicity metrics (lethal residue; LR₅₀s) than in external toxicity metrics (lethal concentration; LC₅₀s): LC₅₀s varied from 2.4 to 66.1 μmol/L, while LR₅₀s varied only from 226 to 413 μmol/kg wet weight. The cadmium body burden appeared to be independent of exposure conditions. From our experimental data, a critical cadmium body residue (324 ± 78 μmol/kg wet weight) associated with 50% lethality was derived. The protective role of DOC and water hardness against cadmium toxicity was evident.

Bioavailability of atrazine, pyrene and benzo[a]pyrene in European river waters

Thirteen river waters and one humic lake water were characterized. The effects of dissolved organic matter (DOM) on the bioavailability of atrazine, pyrene and benzo[a]pyrene (B[a]P) was evaluated. Binding of the chemicals by DOM was analyzed with the equilibrium dialysis technique. For each of the water samples, 24 h bioconcentration factors (BCFs) of the chemicals were measured in Daphnia magna. The relationship between DOM and other water characteristics (including conductivity, water hardness and pH), and bioavailability of the chemicals was studied by performing several statistical analyses, including multiple regression analyses, to determine how much of the variation of BCF values could be explained by the quantity and quality of DOM. The bioavailability of atrazine was not affected by DOM or any other water characteristics. Although equilibrium dialysis showed binding of pyrene to DOM, the bioavailability of pyrene was not significantly affected by DOM. The bioavailability of B[a]P was significantly affected by both the quality and quantity of DOM. Multiple regression analyses, using the quality (ABS270 and HbA%) and quantity of DOM as variables, explained up to 70% of the variation in BCF of B[a]P in the waters studied.

UV-B-Induced acute toxicity of pyrene to the waterflea Daphnia magna in natural freshwaters

The effects of various water characteristics in natural freshwaters on the acute toxicity of one polycyclic aromatic hydrocarbon (PAH), pyrene, to a pelagic invertebrate Daphnia magna was studied under ultraviolet B (UV-B) radiation and in the dark. Pyrene was photoactivated and was more toxic to D. magna in the presence of UV-B radiation. Dissolved organic material (DOM), measured as dissolved organic carbon (DOC), significantly reduced the photoenhanced toxicity of pyrene. Under UV-B radiation the EC(50) values were lower and in relation to the amount of DOM, ranging from 3.0 to 30.0 microg/L pyrene, whereas in the dark they were between 29.2 and 54.8 microg/L and not related to the amount of DOM in the waters. Although the condition and mortality of the daphnids in the control groups were not affected by UV-B irradiation, the increased toxicity was considered to be either an additive or a synergistic effect of both the photomodified pyrene and the stressing light conditions of UV-B. The measured binding of pyrene to DOM was low, although it was related to the amount of DOC. Despite the relatively high intensity of UV-B used, humic substances in the waters remained undegraded. It was thus concluded that with their brownish-yellowish color, waters rich in humic substances decreased the photomodification of the freely dissolved parent compound simply by diminishing the light penetration in these waters and, by implication, contact with the intact compound. These results suggest that DOM in surface waters plays an important role in protecting against the photoinduced toxicity of PAHs.

The kinetics of cadmium in Daphnia magna as affected by humic substances and water hardness

In order to investigate mechanisms causing enhanced toxicity of cadmium in humic lake waters the kinetics of cadmium in Daphnia magna was studied. The uptake rate of cadmium was two times faster in humic lake water than in the humic-free reference water. On the other hand, the depuration rate was equal in humic and reference waters. Thus the acutely lethal concentration in animal is reached faster in humic than in humic-free water. However, altered kinetics of cadmium in humic lake water was also affected by lower water hardness compared to the reference.