ALBERT

Description: Introduction: Pulmonary embolism (PE) contributes to more than 100,000 annual deaths in the United States and is the third most common cause of cardiovascular death. Short-term all-cause mortality rates differ widely, from 2% among low risk normotensive patients to 95% among those experiencing cardiac arrest. Prognostic models for PE help clinicians facilitate decision making but have suboptimal predictive values. The most widely used tool is the simplified Pulmonary Embolism Severity Index (sPESI) - a scoring system which utilizes 6 clinical variables to predict death. Cellular indices, like platelet-lymphocyte ratio (PLR) and neutrophil-lymphocyte ratio (NLR), have been shown to be markers of systemic inflammation and are associated with worsened prognosis in acute PE. Other ratios, such as lymphocyte-monocyte ratio (LMR) and platelet-neutrophil ratio (PNR), have not been fully explored. Given the need to further improve sPESI to better manage PE patients, we sought to determine the association of PLR, NLR, LMR, and PNR with all-cause mortality in patients presenting with acute PE. We also evaluated the additive effect of these cellular indices on the predictive value of sPESI. Methods: We retrospectively investigated patients who were consecutively diagnosed and treated between March 2016 and June 2019 at Loyola Medical Center in Maywood, Illinois and Gottlieb Memorial Hospital in Melrose Park, Illinois. Diagnosis of PE was made using CT pulmonary angiography or ventilation perfusion (VQ) scan. Patients were excluded if there was presence of infection, sepsis, ongoing cancer treatment, or a chronic inflammatory condition at the time of PE diagnosis. Clinical characteristics were collected using the electronic medical record system. Differential complete blood count data was collected within 24 hours prior to PE diagnosis. Mann Whitney U and Chi-Square tests were used to determine associations between all-cause mortality and clinical data. ROC curves were constructed to illustrate the sensitivity and specificity of cellular indices to predict all-cause mortality. Optimal ratio cutoffs were determined using Youden J Index. A composite sPESI score was created using cellular blood indices cutoff values. One point was added to the sPESI score for every additional condition met. Results: Among the 228 PE patients, 48 (21%) were non-survivors with median follow up period of 56 days (IQR: 17-182). Elevated PLR and NLR, as well as decreased LMR, were associated with all-cause mortality (all p 〈 0.01). PNR was not associated with all-cause mortality (p 〉 0.62). PLR 〉 256.7 was predictive of mortality (p 〈 0.01) with sensitivity 54.2% and specificity 85.6%. NLR 〉 5.5 was predictive of mortality (p 〈 0.01) with sensitivity 66.7% and specificity 68.3%. LMR 〈 1.6 was predictive of mortality (p 〈 0.01) with sensitivity 66.7% and specificity 70.8%. sPESI was predictive of mortality (p 〈 0.01) with sensitivity 72.9% and specificity 64.0%. A composite model including sPESI, PLR, NLR, and LMR had further improved predictive abilities for all-cause mortality with sensitivity 85.4% and specificity 66.3% as compared to sPESI alone (AUC: 0.82, 95% CI: 0.76-0.89 vs AUC 0.75, 95% CI: 0.68-0.83). Conclusion: This study demonstrated an association between PLR, NLR, and LMR and all-cause mortality in PE patients. Our findings were consistent with past literature and contribute to the argument that these routine laboratory tests can supplement existing risk prediction models. Lymphopenia as well as elevated neutrophil count are associated with pro-inflammatory states during cardiopulmonary events, which may increase risk for thrombotic events. Platelets, a key component of thrombosis, are significantly decreased immediately after a thrombotic event. The composite sPESI model, including PLR, NLR, and LMR exhibited higher sensitivity which allows for improved detection of patients who are at high risk for death. Future studies are required to assess the predictive value of other routine blood tests on all-cause mortality in this patient population to further optimize sPESI and other predictive tools. Disclosures No relevant conflicts of interest to declare.

Description: Inhibitors of the bacterial enzyme dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase (DapE; EC 3.5.1.18) hold promise as antibiotics with a new mechanism of action. Herein we describe the discovery of a new series of indoline sulfonamide DapE inhibitors from a high-throughput screen and the synthesis of a series of analogs. Inhibitory potency was measured by a ninhydrin-based DapE assay recently developed by our group. Molecular docking experiments suggest active site binding with the sulfonamide acting as a zinc-binding group (ZBG).

Description: Background: Pulmonary Embolism (PE) is a condition that affects a multitude of individuals worldwide. The pathophysiology of PE is multifactorial and complex. Measuring levels of biomarkers in PE patient plasma may be predictive of patient outcomes in terms of survival, and such biomarkers could be correlated to other parameters such as white cell counts and their ratios. Adhesion molecules, such as selectins, have been predicted to play a role in the pathophysiology of PE, however their relationship to other cellular parameters is not fully explored. P-selectin is found on platelets, and is involved in the gathering of platelets in thrombotic states. Meanwhile, E and L-selectin contribute to cellular rolling that occurs in states of inflammation. White blood cell counts are routinely obtained from patient blood analysis. Selectins, including Platelet (P), Endothelial (E), and Leukocyte (L) Selectins may possess relationships to the white cell profiles including neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), platelet-neutrophil ratio (PNR), lymphocyte-monocyte ratio (LMR), and monocyte-neutrophil ratio (MNR). Selectins can also be correlated to total platelet and white cell counts. Mortality outcomes in PE patients may be associated with altered levels of hemostatic and inflammatory biomarkers such as selectins. Materials and Methods: Blood samples were acquired from 100 patients diagnosed with acute PE between March 2016 and June 2019 at Loyola University Medical Center in Maywood, IL. Enzyme Linked Immunosorbent Assays (ELISA) were used to quantify levels of P, E, and L selectins in the plasma of PE patients. Other coagulation and inflammatory biomarkers, including Tumor Necrosis Factor Alpha (TNFa), D-dimer, Plasminogen Activating Inhibitor-1 (PAI-1), Matrix Metalloprotease-9 (MMP-9), C-Reactive Protein (CRP), micro particles, and alpha-2-antiplasmin were also quantified. Patient chart review was conducted assessing for levels of platelets, neutrophils, lymphocytes, and monocytes. Appropriate cellular ratios were calculated. Patient outcomes in the form of mortality were noted. Spearman non-parametric analysis and Wilcoxon-Mann-Whitney Tests were conducted using Graphpad PRISM software. Results: All of the biomarkers studied exhibited an increase in PE patient plasma, ranging from 2 fold to 34.6 fold increase, with the exception of alpha-2-antiplasmin, E-selectin, and L-selectin, as shown in Table 1. D-dimer, MMP-9, and CRP show the most pronounced increase in PE patients. No statistically significant correlations were noted between P, E, and L-selectins and NLR, PLR, PNR, LMR, or MNR. P-selectin was positively correlated with platelet count (r=.22, p=.032, 95% CI=0.01293 to 0.4084, n=95). L-selectin was not found to be significantly correlated with white count, but a positive trend was still evident (r=.13, p=.22, CI= -0.08329 to 0.3250, n=95). Within the patient pool, 12% of patients were deceased, while 88% survived. L-selectin and all-cause mortality were significantly correlated at an alpha level of .05 (p=.04). Conclusion: These studies demonstrate the marked dysregulation of hemostatic and inflammatory biomarkers associated with alterations of cellular indices. In particular, P and L selectin demonstrated some relationship to platelets and white count. L-selectin levels are significantly correlated to all-cause mortality. Measuring levels of L-selectin in PE patients may provide insight into mortality outcomes for pulmonary embolism patients. Our results are suggestive of the positive predictive value of L-selectin in PE patients. Profiling of various biomarkers, in particular selectins, may be helpful in the risk stratification of PE patients. Adding such a parameter to patient analysis may provide better prognostic information, which may be helpful in their clinical management. Disclosures No relevant conflicts of interest to declare.

Description: Background : Sepsis is characterized by a simultaneous activation of inflammation and hemostasis in response to microbial infection. This systemic inflammatory response is due to the release of pro-inflammatory cytokines, pro-coagulants and adhesion molecules from immune cells and/or damaged endothelial tissue. Simultaneous activation of coagulation and fibrinolysis leads to consumption coagulopathy and severe vascular dysfunction. Profiling of biomarkers of hemostatic activation and inflammation along with the measurement of coagulation parameters has provided useful data in the understanding of the pathogenesis of sepsis. This study was designed to profile biomarkers of hemostatic activation, inflammation and endothelial dysfunction along with the measurement of coagulation parameters in a defined clinically confirmed sepsis population in conjunction with an IRB approved clinical trial. Materials & Methods: Citrated blood samples were collected from sepsis patients with suspected or confirmed infection, and organ dysfunction as defined by a SOFA ³ baseline. Plasma samples from septic shock patients were collected in citrated tubes within 72 hours of ICU admission under an IRB approved protocol in conjunction with an ongoing trial at the University of Utah and Veteran's Affair FFC Health Care System VAMC. Normal controls were comprised of commercially available 25 male and 25 female citrated plasma samples (George King Biomedical, Overland Park, Kansas City). Such biomarkers as CRP, PAI-1, D-Dimer, vWF and microparticle tissue factor complex (MP-TF) were measured using a commercially available sandwich ELISA methods. Nitric oxide (NO) levels were measured using a commercially available Griess reaction based colorimetric method. PT/INR, aPTT and fibrinogen measurements were based on clot based assays. All results were compiled as mean ± SD and SEM. Correlation analysis was carried out to determine relevance between different parameters. Results: Most of the biomarkers of hemostatic activation and inflammation were elevated in patients with sepsis as shown on table 1a, CRP (66 fold) and D-Dimer (23 fold) showed the most pronounced increase in comparison to the control. Other parameters also showed increase levels including MP-TF (5.3 fold), PAI-1 (3.5 fold), vWF (3.1 fold) and NO (3.0 fold). Clotting parameters such as PT/INR (2.0 fold), aPTT (2.5 fold) and fibrinogen (2.0 fold) were also significantly elevated in the sepsis patients. These differences were significant (p value ≤0.0009) for all of the parameters except for NO (p value 0.0937) and fibrinogen (p value 0.4694). As shown on table 1b, there was no correlation between various biomarkers and fibrinogen in the sepsis patients. Summary & Conclusion: In comparison to the control group, the sepsis patients showed wide variations in all of the parameters investigated in this study. The marked prolongation of PT and aPTT are suggestive of both the extrinsic and intrinsic pathway defects and consumption of clotting factors. The aPTT data showed wider scatter in comparison to PT data. The fibrinogen levels were also elevated and nearly 1/3 of the patients showed 〉1000 mg/dL levels. The markedly higher level of CRP in the sepsis group are indicative of severe inflammatory response. Marked elevation of D-Dimer is indicative of endogenous fibrin formation and its consumption consistent with activation of secondary fibrinolysis. MP-TF, vWF and PAI-1 were also increased in the sepsis patients suggesting marked endothelial dysfunction. This is consistent with increased NO levels which may be due to induction of iNOS in the endothelial lining of sepsis patients. These results further underscore the multifactorial pathophysiology of sepsis which results in the dysregulation of hemostasis, upregulation of inflammatory responses and generalized endothelialopathy. Profiling of the biomarkers included in this study and coagulation parameters may be helpful in the risk stratification and clinical management of patients with sepsis and related disorders. Disclosures No relevant conflicts of interest to declare.