Era of URINE

Urine has been considered to be able to reflect diseases since ancient time. But the era of urine never comes. Blood is thought to connect with all the organs and exchange materials with them. Blood is stable. Any changes happened in blood are believed more reliable, at least compare to urine. In the history of medicine, this period of time is the era of blood. In this period of medicine history, early diagnosis is still hard, still not early enough to stop many diseases to save lives. Researchers are trying very hard to make machines and assays to be more sensitive. Many many people are still suffering and even dying because of late diagnosis. A new urimarker theory sheds some light on this wondering field. The theory starts with the analysis of the biomarker experiments design. In all the biomarker studies, there are at least two groups of samples. No matter what are measured, the values of the two groups are compared to find the differences, the changes. From this common scheme, change is emphasized in a new biomarker definition, which is, biomarker is the measurable changes associated with the disease. With this new definition in mind,it is not difficult to reason where we should be looking for these changes. The concept of the regulation of the internal environment was described by French physiologist Claude Bernard in 1865, and the word homeostasis was coined by Walter Bradford Cannon in 1926. Based on the homeostasis of internal environment theory, biomarker, which is change, should be found earlier and more sensitively in urine,which is full of changes, rather than blood, which is rather stable in the early phase of disease processes. The reason we failed to realize the potential of urine was because almost all the studies were done in clinical samples. Many confounding factors were not even considered. And with so many factors to balance, the sample size was never large enough to reach verifiable results. The roadmap of urimarker was then proposed to start the discovery phase with animal models. Confounding factors are minimized. Now more and more evidences that support this urimarker theory are emerging in animal model studies.