The impact of tracheotomy on levels of procalcitonin in patients without sepsis: a prospective study

OBJECTIVE:Procalcitonin is a reliable biomarker of infection and sepsis. We aimed to determine whether tracheotomy influences the procalcitonin concentrations in patients without sepsis and assess whether operative duration and procedure affect the peak procalcitonin level.METHODS:A total of 38 non-septic patients who required a tracheotomy underwent either a percutaneous dilatational tracheotomy (n=19) or a surgical tracheotomy (n=19). Procalcitonin levels were measured at the beginning of the tracheotomy and at 2 h, 4 h, 8 h, 24 h, 48 h and 72 h after the procedure.RESULTS:The baseline procalcitonin concentration before the tracheotomy was 0.24±0.13 ng/mL. The postoperative levels increased rapidly, with a 4-fold elevation after 2 h, reaching a peak 4 h later with a 5-fold increase over baseline. Thereafter, the levels gradually returned to 2-fold greater than the baseline level within 72 h. The peak levels of procalcitonin showed a significant positive correlation with operative durations (r=0.710,

Flowchart of grouping subjects.

<p>Flowchart of grouping subjects.</p

Characterization of IFN-γ responses in patients and MTB in the lesions by QuantiFERON and Real-Time PCR.

*<p>p<0.05, **p<0.001 vs. the controls.</p

The nucleotide sequences of the primers and probes used in fusion PCR and Real-Time PCR.

<p>The nucleotide sequences of the primers and probes used in fusion PCR and Real-Time PCR.</p

The demographic and clinical characteristics of subjects.

a<p>Recorded vaccination history or skin scars on the arm or pelma.</p

Tuning of Electrical Transport Performance in La_0.67Sr_0.33MnO₃ Films by a Sr₄Al₂O₇ Buffer Layer for Freestanding Membrane-Based Devices

Strain engineering of the electrical and magnetic properties of perovskite manganites has attracted reasonable attention during the last decades. Here, we introduce a newly discovered Sr4Al2O7 as a buffer layer and achieve a successful tuning of the electrical transport properties of the La0.67Sr0.33MnO3 film grown by pulsed laser deposition via controlling the thickness and crystallinity of Sr4Al2O7. For a poorly crystallized Sr4Al2O7 buffer layer, the metallic and insulating state of La0.67Sr0.33MnO3 can be modulated by a small range of Sr4Al2O7 thickness, which is ∼2 nm for a film grown on LaAlO3 and ∼4 nm on SrTiO3 due to the different lattice mismatch. This Sr4Al2O7 buffer layer-controlled epitaxial growth and epitaxial strain provides a strategy to largely modulate the physics properties of perovskite manganites by a small change of the buffer layer. After dissolving Sr4Al2O7, the electrical transport properties of La0.67Sr0.33MnO3 can be preserved well in the freestanding films, showing the promising application potential for innovative electronic devices