Identification and differentiation of bone tumors by the active radiometry

The study discusses the possibility of non-invasive radiometric tumors diagnosis of the musculoskeletal system using a new diagnostic technology – an active resonance radiometry. An active radiometry allows you to record ultra-weak electromagnetic radiation of tissues 1000 MHz when sensing radiation frequency of 65 GHz and reflects the state of the vascular permeability and the activity of transcapillary exchange of water. The study shows the possibility of identification and differentiation of tumors of the musculoskeletal system on the basis of the analysis of the intensity of transcapillary exchange in tissues by means of an active radiometry.

Transient transcapillary exchange of water driven by osmotic forces in the heart

Osmotic transient responses in organ weight after changes in perfusate osmolarity have implied steric hindrance to small-molecule transcapillary exchange, but tracer methods do not. We obtained osmotic weight transient data in isolated, Ringer-perfused rabbit hearts with NaCl, urea, glucose, sucrose, raffinose, inulin, and albumin and analyzed the data with a new anatomically and physicochemically based model accounting for 1) transendothelial water flux, 2) two sizes of porous passages across the capillary wall, 3) axial intracapillary concentration gradients, and 4) water fluxes between myocytes and interstitium. During steady-state conditions ∼28% of the transcapillary water flux going to form lymph was through the endothelial cell membranes [capillary hydraulic conductivity ( Lp) = 1.8 ± 0.6 × 10–8 cm · s–1 · mmHg–1], presumably mainly through aquaporin channels. The interendothelial clefts (with Lp = 4.4 ± 1.3 × 10–8 cm · s–1 · mmHg–1) account for 67% of the water flux; clefts are so wide (equivalent pore radius was 7 ± 0.2 nm, covering ∼0.02% of the capillary surface area) that there is no apparent hindrance for molecules as large as raffinose. Infrequent large pores account for the remaining 5% of the flux. During osmotic transients due to 30 mM increases in concentrations of small solutes, the transendothelial water flux was in the opposite direction and almost 800 times as large and was entirely transendothelial because no solute gradient forms across the pores. During albumin transients, gradients persisted for long times because albumin does not permeate small pores; the water fluxes per milliosmolar osmolarity change were 200 times larger than steady-state water flux. The analysis completely reconciles data from osmotic transient, tracer dilution, and lymph sampling techniques.