Sustained intraoperative allergic reaction to chlorhexidine: A case report.

Physicians should be prepared for the presentation and treatment of an anaphylactic reaction in a patient who has been exposed to chlorhexidine perioperatively and consider a sustained source of allergic exposure when faced with a refractory response to treatment.

No Drain, No Problem: Serum-Based Marker Prediction of Clinically Relevant Postoperative Pancreatic Fistula.

BACKGROUND: Postoperative day (POD) 1 drain amylase concentration (DAC) is considered the most accurate predictor for the development of a clinically relevant postoperative pancreatic fistula (CR-POPF) after pancreaticoduodenectomy (PD). Recent studies have associated drain placement with negative postoperative outcomes. This study aims to evaluate multiple biochemical markers and their associations with CR-POPF development in order to identify a reliable, non-drain dependent alternative to DAC. METHODS: This is a review of 53 consecutive PD patients between 2021 and 2022. Albumin, C-reactive protein (CRP), C-reactive protein-to-albumin ratio (CAR), DAC, white blood cell count, and procalcitonin values were compared by CR-POPF status. The discriminatory abilities of CAR, CRP, and DAC for CR-POPF were compared using receiver operating characteristic (ROC) curves. RESULTS: Six of 51 included patients developed a CR-POPF. Receiver operating characteristic curve analysis produced an area under the curve of .977 for POD 1 DAC (cut-off 5131.0 IU/L, sensitivity 100%, specificity 95.5%), .858 for POD 1 CRP (cut-off 52.5 mg/L, sensitivity 100%, specificity 72.7%), and 1.000 for POD 3 CAR (cut-off 99.2, sensitivity and specificity 100%). POD 3 CAR produced a positive and negative predictive value of 100%. CONCLUSION: The CAR and CRP provide early and accurate identification of patients with post-PD CR-POPFs. These markers offer a method of safe CR-POPF detection, when the gold standard DAC is unavailable, ultimately allowing for early intervention and patient rescue.

Insights into the importance of WPD-loop sequence for activity and structure in protein tyrosine phosphatases.

Protein tyrosine phosphatases (PTPs) possess a conserved mobile catalytic loop, the WPD-loop, which brings an aspartic acid into the active site where it acts as an acid/base catalyst. Prior experimental and computational studies, focused on the human enzyme PTP1B and the PTP from Yersinia pestis, YopH, suggested that loop conformational dynamics are important in regulating both catalysis and evolvability. We have generated a chimeric protein in which the WPD-loop of YopH is transposed into PTP1B, and eight chimeras that systematically restored the loop sequence back to native PTP1B. Of these, four chimeras were soluble and were subjected to detailed biochemical and structural characterization, and a computational analysis of their WPD-loop dynamics. The chimeras maintain backbone structural integrity, with somewhat slower rates than either wild-type parent, and show differences in the pH dependency of catalysis, and changes in the effect of Mg2+. The chimeric proteins' WPD-loops differ significantly in their relative stability and rigidity. The time required for interconversion, coupled with electrostatic effects revealed by simulations, likely accounts for the activity differences between chimeras, and relative to the native enzymes. Our results further the understanding of connections between enzyme activity and the dynamics of catalytically important groups, particularly the effects of non-catalytic residues on key conformational equilibria.

Application of Structural Retinal Biomarkers to Detect Cognitive Impairment in a Primary Care Setting.

Background: Despite the diagnostic accuracy of advanced neurodiagnostic procedures, the detection of Alzheimer's disease (AD) remains poor in primary care. There is an urgent need for screening tools to aid in the detection of early AD. Objective: This study examines the predictive ability of structural retinal biomarkers in detecting cognitive impairment in a primary care setting. Methods: Participants were recruited from Alzheimer's Disease in Primary Care (ADPC) study. As part of the ADPC Retinal Biomarker Study (ADPC RBS), visual acuity, an ocular history questionnaire, eye pressure, optical coherence tomography (OCT) imaging, and fundus imaging was performed. Results: Data were examined on n = 91 participants. The top biomarkers for predicting cognitive impairment included the inferior quadrant of the outer retinal layers, all four quadrants of the peripapillary retinal nerve fiber layer, and the inferior quadrant of the macular retinal nerve fiber layer. Conclusion: The current data provides strong support for continued investigation into structural retinal biomarkers, particularly the retinal nerve fiber layer, as screening tools for AD.