Cytokines correlate with age in healthy volunteers, dialysis patients and kidney-transplant patients

T-cell functions are currently used as biomarkers for the pharmacodynamic monitoring of immunosuppressive drugs or as disease biomarkers of inflammation/sepsis and organ rejection. In order to evaluate co-factors potentially influencing the expression of the immunological biomarkers, we explored T-cell proliferation, T-cell activation (CD25 and CD71 expressions) and intra-lymphocyte cytokine production (interleukin (IL)-2 and tumor necrosis factor (TNF)-α) in healthy volunteers, dialysis patients and stable kidney-transplant patients treated with standard immunosuppressive therapy, i.e. tacrolimus, mycophenolic acid with or without steroids. Age was positively correlated with TNF-α expression in all three patient populations, and with IL-2 expression in healthy volunteers and kidney-transplant patients. Further age was correlated with inhibition of lymphocyte proliferation in healthy volunteers and with the T-cell activation marker CD25 in kidney-transplant patients. In healthy volunteers lymphocyte proliferation was higher in woman as compared to men. Other biomarkers of T-cell function were independent of the gender. In the kidney-transplant patient group a significantly lower expression of all biomarkers of T-cell functions compared to healthy volunteers and dialysis patients. In dialysis patients we found significant increased IL-2 expression compared to healthy volunteers, while the other T-cell functions were not significantly different. Further time on dialysis had no effect on the level of biomarker expression. In conclusion we found decreased T-cell functions in kidney-transplant patients compared to healthy volunteers and dialysis patients, increased IL-2 expression in dialysis patients compared to healthy volunteers and in all three populations we found a correlation of age and intra-T-lymphocyte TNF-α expression.     

Stability, molecular structures and magnetic properties of dinuclear iron complexes supported by benzoic hydrazide derivative ligands

We report experimental evidences including molecular solid-state structure determinations, magnetic measurements and EPR studies for the formation (in the solid-state) of novel dinuclear (μ-OMe)₂(L)₄ complexes (HL are 2-ylidenhydrazidebenzoic-1,3-dithiolane acid and N′-cyclopentylidene-2-hydroxybenzohydrazide). The two novel dinuclear iron compounds described in the present contribution exhibit antiferromagnetic intra-molecular coupling. Crystal structures of the supporting ligands as well as one mononuclear species have also been determined.     

Subsite mapping of purified glucoamylase I, II, III produced by Arthrobotrys amerospora ATCC 34468

Arthrobotrys amerospora ATCC 34468 produced glucoamylase in a medium containing maize starch as carbon source. On native PAGE, crude glucoamylase showed three isoenzymes which were designated as Glu I, Glu II, Glu III according to their electrophoretic mobility. These were purified by column chromatography techniques. The energy of binding for each glucoamylase was calculated using Hiromi's kinetic based calculation. At subsite 1, the binding energies for Glu I, II and III were found to be negative.     

Time-gated interferometric detection increases Raman scattering to fluorescence signal ratio in biological samples

Attainable levels of signal-to-background ratio (SBR) in Raman spectroscopy of biological samples is limited by the presence of endogenous fluorophores. It is customary to remove the ubiquitous fluorescence background using postacquisition data processing. However, new approaches are needed to reduce background contributions and maximize the fraction of the sensor dynamical range occupied by Raman photons. Time-resolved detection using pulsed lasers and time-gated measurements can be used to address the signal-to-background problem in biological samples by limiting light detection to nonresonant interaction phenomena with relaxation time scales occurring on sub-nanosecond time scales, thereby excluding contributions from resonant phenomena such as fluorescence. A time-gated Fourier-transform spectrometer was assembled using a commercially available interferometer, a single channel single-photon avalanche diode and time tagging electronics. A time gate of 300 ps increased the signal-to-background-ratio of the 1440 cm^?1 Raman band from 36% to 69% in an olive oil sample hereby demonstrating the potential of this approach for autofluorescence suppression.