Anesthesia and surgery-induced elevation of CSF sTREM2 is associated with early cognitive dysfunction after thoracoabdominal aortic dissection surgery

Abstract Purpose Soluble triggering receptor expressed on myeloid cells 2 (sTREM2) concentration is increased in cerebrospinal fluid (CSF) in early symptomatic phase of Alzheimer’s disease (AD). This study investigated whether CSF sTREM2 has a relationship with early cognitive dysfunction following surgery in cardiac surgery patients. Methods A total of 82 patients undergoing thoracoabdominal aortic replacement were recruited in this study. Neuropsychological testing battery was conducted before and after surgery. Postoperative cognitive dysfunction (POCD) was defined as a Z-score > 1.96 on at least 2 different tests or Telephone Interviews for Cognitive Status-Modified (TICS-M) score < 27. The CSF and serum sTREM2, Aβ42, T-tau and P-tau were collected and measured by ELISA on day before surgery and postoperative day 3. Results Patients were classified into POCD (n = 34) and non-POCD (n = 48) groups according to Z-score. Compared to non-POCD group, the levels of CSF sTREM2 (p < 0.001) and serum sTREM2 (p = 0.001) were significantly higher in POCD group on postoperative day 3. The levels of Aβ42 (p = 0.005) and Aβ42/T-tau ratio (p = 0.036) were significantly lower in POCD group on postoperative day 3. Multivariate logistic regression analysis revealed that higher value of postoperative CSF sTREM2 (odds ratio: 1.06, 95% confidence interval: 1.02–1.11, p = 0.009), age (OR: 1.15, 95%CI: 1.03–1.28, p = 0.014) and POD duration (OR: 2.47, 95%CI: 1.15–5.29, p = 0.02) were the risk factors of POCD. Conclusion This study indicates that anesthesia and surgery-induced elevation of CSF sTREM2 is associated with an increased risk of early cognitive dysfunction following surgery

Imaging Chemical Kinetics of Radical Polymerization with an Ultrafast Coherent Raman Microscope

Numerous mechanisms have been proposed for polymerization to provide qualitative and quantitative prediction of how monomers spatially and temporally arrange into the polymeric chains. However, less is known about this process at the molecular level because the ultrafast chemical reaction is inaccessible for any form of microscope so far. Here, to address this unmet challenge, a stimulated Raman scattering microscope based on collinear multiple beams (COMB‐SRS) is demonstrated, which allows label‐free molecular imaging of polymer synthesis in action at speed of 2000 frames per second. The field of view of the developed 2 kHz SRS microscope is 30 × 28 µm2 with 50 × 46 pixels and 7 µs dwell time. By catching up the speed of chemical reaction, COMB‐SRS is able to quantitatively visualize the ultrafast dynamics of molecular vibrations with submicron spatial resolution and sub‐millisecond temporal resolution. The propagating polymer waves driven by reaction rate and persistent UV initiation are observed in situ. This methodology is expected to permit the development of novel functional polymers, controllable photoresists, 3D printing, and other new polymerization technologies.Published versio