Thermal analysis of synovial fluids in different stages of osteoarthritis and after bacterial infections

The analysis of synovial fluid is an important method in diagnosing and handling septic arthritis. To achieve a quick diagnosis could be a great advantage in the therapy. The differential scanning calorimetry (DSC) proved to be a useful technique in the differential diagnosis of tumors using blood plasma or sera. The aim of this paper is to show up some characteristic thermal parameters in the diagnosis of different grades of arthritis, which are in good agreement with the severity of disease checked by conventional X-ray supported grading. To follow the effect of different bacterial strains, the synovial fluids were inoculated by three types of bacterial strains (with 103–105 CFU mL−1 concentrations) at 37 °C and stored trough 24 h. After that, they were denatured in 20–90 °C temperature range with 0.3 K min−1 scanning rate. The change in the maximum denaturation temperature (Tm) and calorimetric enthalpy (∆H) monitored the severity of sepsis and depended on the type of bacteria. The proliferation characteristics of bacteria should be strain specific. The synovial fluid samples inoculated with the most frequently occurring bacteria were monitored in isotherm mode (isoperibol calorimeter) at 37 °C up to the end of the proliferation. The isoperibolic scans clearly demonstrated specific, concentration-dependent representative curves in case of each bacterium (duration of proliferation, maximum of proliferation rates, etc.). Therefore, thermal analysis of human synovial fluid samples by DSC or isoperibolic calorimetry could be a useful tool in the staging of osteoarthritis and the diagnostics of septic arthritis.

Synthesis and Standard Molar Formation Enthalpy of Plate Shape NaZnPO4·H2O

Plate shape NaZnPO4·H2O was synthesized by solid-state reaction at low temperature and characterized by X-Ray Diffraction, Scanning electron microscope and elemental analysis. Thermochemical study was performed with an isoperibol solution calorimeter. Based on Hess’s law, thermochemical cycl was designed to determine the dissolution enthalpies of reactants and products using a solution-reaction isoperibol calorimeter at 298.15 K, and the molar reaction enthalpy was calculated on the basis of above dissolution enthalpies. The results show that the obtained product is plate shape NaZnPO4·H2O. The standard molar formation enthalpy of the NaZnPO4·H2O is ΔfHm [NaZnPO4·H2O,s]= -1967.18 ± 0.69 kJ•mol-1.

Specific heat of InBi below 30 K

There was difficulty in establishing good thermal contact with InBi, a very anisotropic material. This is not believed to have affected results from the 2.5–30 K adiabatic calorimeter. However, results from the 0.35–3 K isoperibol calorimeter are a few percent high in the overlap range owing to uncompensated heat loss during heating periods. Consequently there is some uncertainty in the determination of the electronic specific heat but little uncertainty in Debye temperatures above 1 K (because the lattice specific heat is so large). Despite the great anisotropy, mass-layering, and easy cleaving in one direction, the variation of Debye temperature with temperature is quite normal, there being no evidence of two-dimensional behavior (cf. graphite). The preferred analysis gives the electronic specific heat coefficient as 97.1 ± 0.8 μcal K−2 g-at.−1 (406 ± 3 μJ K−2 g-at.−1) and the low temperature limiting value of Debye temperature as 139.8 ± 0.4 K.