[Diagnostic value of molecular biomarkers of infection in screening by Sepsis-3 criteria]. / Diagnosticheskoe znachenie molekuliarnykh biomarkerov infektsionnogo protsessa pri skrininge po kriteriiam Sepsis-3.

AIM: To compare diagnostic value of molecular biomarkers of sepsis in patients with surgical infection in screening via Sepsis-2 (Surviving Sepsis Campaign 2012, SSC 2012) and Sepsis-3 (The Third International Consensus Definitions for Sepsis and Septic Shock) criteria. MATERIAL AND METHODS: Septic patients according to Sepsis-2 and Sepsis-3 criteria were identified from general population with surgical infection. Logistic regression models quality was the criterion for assessment of diagnostic value of molecular biomarkers. Risk factors importance was estimated via odds ratios (OR) calculation. RESULTS: Sepsis-3 ROC-AUC for procalcitonin increased up to 0.933, cut-off value 2.35 ng/ml (Sepsis-2 AUC 0.768 (p=0.004), cut-off 1.72 ng/ml). Sepsis-3 ROC-AUC for presepsin increased up to 0.932, cut-off value - 772 pg/ml (Sepsis-2 AUC 0.865, cut-off 567 pg/ml). The highest risk of sepsis was observed in systemic response to inflammation combined with organ dysfunction (OR 69.667, S 0.636; 95% CI 20.03-242.4) (Sepsis-2 - OR 9.25, S 0.548; 95% CI 3.2-27.1, p<0.001). Increased levels of both biomarkers significantly increased the risk of sepsis (OR 22.5, S 0.794; 95% CI 4.74-106.6 and OR 20.97, S 0.58; 95% CI 6.705-65.6, respectively). CONCLUSION: Organ dysfunction assessment by Sepsis-3 criteria improves diagnostic possibilities in patients with suspected sepsis. Maximum predictive value is observed for systemic inflammation response combined with organ dysfunction. In these patients procalcitonin and presepsin are characterized by equivalent high diagnostic potential for evidence of infectious nature of the disease. Increased level of these markers can serve as a basis for antimicrobial therapy administration.

Ni(2+)-zeolite/ferrosphere and Ni(2+)-silica/ferrosphere beads for magnetic affinity separation of histidine-tagged proteins.

Magnetic Ni(2+)-zeolite/ferrosphere and Ni(2+)-silica/ferrosphere beads (Ni-ferrosphere beads - NFB) of a core-shell structure were synthesized starting from coal fly ash ferrospheres having diameters in the range of 0.063-0.050 mm. The strategy of NFB fabrication is an oriented chemical modification of the outer surface preserving the magnetic core of parent beads with the formation of micro-mesoporous coverings. Two routes of ferrosphere modification were realized, such as (i) hydrothermal treatment in an alkaline medium resulting in a NaP zeolite layer and (ii) synthesis of micro-mesoporous silica on the glass surface using conventional methods. Immobilization of Ni(2+) ions in the siliceous porous shell of the magnetic beads was carried out via (i) the ion exchange of Na(+) for Ni(2+) in the zeolite layer or (ii) deposition of NiO clusters in the zeolite and silica pores. The final NFB were tested for affinity in magnetic separation of the histidine-tagged green fluorescent protein (GFP) directly from a cell lysate. Results pointed to the high affinity of the magnetic beads towards the protein in the presence of 10 mM EDTA. The sorption capacity of the ferrosphere-based Ni-beads with respect to GFP was in the range 1.5-5.7 mg cm(-3).

Ca(2+)-triggered coelenterazine-binding protein from Renilla as an enzyme-dependent label for binding assay.

The recombinant Ca(2+)-triggered coelenterazine-binding protein (CBP) from Renilla muelleri was investigated as a biospecifically labeled molecule for in vitro assay applications. The protein was shown to be stable in solutions in the frozen state, as well as stable under heating and to chemical modifications. Conjugates with biotin, oligonucleotide, and proteins were obtained and applied as biospecific molecules in a solid-phase microassay. CBP detection was performed with intact (no modifications were made) Renilla luciferase in the presence of calcium, and the detection limit was found to be 75 amol. Model experiments indicate that this approach shows much promise, especially with regard to the development of multianalytical systems.