Commutability Assessment of Candidate Reference Materials for Lipoprotein(a) by Comparison of a MS-based Candidate Reference Measurement Procedure with Immunoassays.

BACKGROUND: Elevated concentrations of lipoprotein(a) [Lp(a)] are directly related to an increased risk of cardiovascular diseases, making it a relevant biomarker for clinical risk assessment. However, the lack of global standardization of current Lp(a) measurement procedures (MPs) leads to inconsistent patient care. The International Federation for Clinical Chemistry and Laboratory Medicine working group on quantitating apolipoproteins by mass spectrometry (MS) aims to develop a next-generation SI (International system of units)-traceable reference measurement system consisting of a MS-based, peptide-calibrated reference measurement procedure (RMP) and secondary serum-based reference materials (RMs) certified for their apolipoprotein(a) [apo(a)] content. To reach measurement standardization through this new measurement system, 2 essential requirements need to be fulfilled: a sufficient correlation among the MPs and appropriate commutability of future serum-based RMs. METHODS: The correlation among the candidate RMP (cRMP) and immunoassay-based MPs was assessed by measuring a panel of 39 clinical samples (CS). In addition, the commutability of 14 different candidate RMs was investigated. RESULTS: Results of the immunoassay-based MPs and the cRMPs demonstrated good linear correlations for the CS but some significant sample-specific differences were also observed. The results of the commutability study show that RMs based on unspiked human serum pools can be commutable with CS, whereas human pools spiked with recombinant apo(a) show different behavior compared to CS. CONCLUSIONS: The results of this study show that unspiked human serum pools are the preferred candidate secondary RMs in the future SI-traceable Lp(a) Reference Measurement System.

Glucose and lipopolysaccharide differentially regulate fibroblast growth factor 21 in healthy male human volunteers - A prospective cross-over trial.

Fibroblast growth factor 21 (FGF21) affects the regulation of metabolism. Additionally, anti-inflammatory properties are attributed to FGF21, and studies in animals and humans show conflicting results. This study aimed to investigate how FGF21 is affected by glucose and lipopolysaccharide (LPS) in humans. Therefore, FGF21 was measured eight times at different time points within 48 h in this prospective cross-over trial after glucose and LPS on two different study days. The study included ten healthy, non-smoking male subjects aged 18-40. Repeated measures analysis of variance and paired t-test as post hoc analysis were applied. The administration of glucose and LPS resulted in a significant difference in regulating FGF21 (p < 0.001). After glucose administration, FGF21 declined sharply at 360 min, with a subsequent steep increase that exceeded baseline levels. LPS induced a drop in FGF21 after 180 min, while the baseline concentrations were not reached. After 180 min and 24 h, a statistically significant difference was demonstrated after adjusting the Bonferroni-Holm method. So, our results support the hypothesis that glucose and LPS differentially affect the human expression of FGF21 over 48 h.

Afamin predicts the prevalence and incidence of nonalcoholic fatty liver disease.

OBJECTIVES: In the general population, increased afamin concentrations are associated with the prevalence and incidence of metabolic syndrome as well as type 2 diabetes. Although metabolic syndrome is commonly associated with nonalcoholic fatty liver disease (NAFLD), there exist no information on afamin and NAFLD. METHODS: Afamin concentrations were cross-sectionally measured in 146 Austrian patients with NAFLD, in 45 patients without NAFLD, and in 292 age- and sex-matched healthy controls. Furthermore, the feasibility of afamin to predict incident NAFLD was evaluated in 1,434 adult participants in the population-based Cardiovascular Risk in Young Finns Study during a 10-year follow-up. RESULTS: Median afamin concentrations were significantly higher in NAFLD patients (83.6 mg/L) than in patients without NAFLD (61.6 mg/L, p<0.0001) or in healthy controls (63.9 mg/L, p<0.0001). In age- and sex-adjusted logistic regression analyses a 10 mg/L increase of afamin was associated with a 1.5-fold increase of having NAFLD as compared with patients without NAFLD and the risk was even two-fold when compared with healthy controls. In the population-based cohort, afamin concentrations at baseline were significantly lower in participants without NAFLD (n=1,195) than in 239 participants who developed NAFLD (56.5 vs. 66.9 mg/L, p<0.0001) during the 10-year follow up, with highest afamin values observed in individuals developing severe forms of NAFLD. After adjustment for several potentially confounding parameters, afamin remained an independent predictor for the development of NAFLD (OR=1.37 [95% CI 1.23-1.54] per 10 mg/L increase, p<0.0001). CONCLUSIONS: Afamin concentrations are increased in patients with NAFLD and independently predict the development of NAFLD in a population-based cohort.

Intravenous administration of LPS activates the kynurenine pathway in healthy male human subjects: a prospective placebo-controlled cross-over trial.

BACKGROUND: Administration of lipopolysaccharide (LPS) from Gram-negative bacteria, also known as the human endotoxemia model, is a standardized and safe model of human inflammation. Experimental studies have revealed that peripheral administration of LPS leads to induction of the kynurenine pathway followed by depressive-like behavior and cognitive dysfunction in animals. The aim of the present study is to investigate how acute intravenous LPS administration affects the kynurenine pathway in healthy male human subjects. METHODS: The present study is a prospective, single-blinded, randomized, placebo-controlled cross-over study to investigate the effects of intravenously administered LPS (Escherichia coli O113, 2 ng/kg) on tryptophan and kynurenine metabolites over 48 h and their association with interleukin-6 (IL-6) and C-reactive protein (CRP). The study included 10 healthy, non-smoking men (18-40 years) free from medication. Statistical differences in tryptophan and kynurenine metabolites as well as associations with IL-6 and CRP in LPS and placebo treated subjects were assessed with linear mixed-effects models. RESULTS: Systemic injection of LPS was associated with significantly lower concentrations of plasma tryptophan and kynurenine after 4 h, as well as higher concentrations of quinolinic acid (QUIN) after 48 h compared to the placebo injection. No differences were found in kynurenic acid (KYNA) or picolinic acid plasma concentrations between LPS or placebo treatment. The KYNA/kynurenine ratio peaked at 6 h post LPS injection while QUIN/kynurenine maintained significantly higher from 3 h post LPS injection until 24 h. The kynurenine/tryptophan ratio was higher at 24 h and 48 h post LPS treatment. Finally, we report an association between the kynurenine/tryptophan ratio and CRP. CONCLUSIONS: Our findings strongly support the concept that an inflammatory challenge with LPS induces the kynurenine pathway in humans, activating both the neurotoxic (QUIN) and neuroprotective (KYNA) branch of the kynurenine pathway. TRIAL REGISTRATION: This study is based on a study registered at ClinicalTrials.gov, NCT03392701 . Registered 21 December 2017.

Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) Is Not Induced in Artificial Human Inflammation and Is Not Correlated with Inflammatory Response.

Lipoproteins, as well as proprotein convertase subtilisin/kexin type 9 (PCSK9), have been shown to play a key role in the innate immune response. However, knowledge about the role and kinetics of PCSK9 in human inflammation is currently insufficient. This study aimed to investigate the interaction between inflammation and lipid metabolism, including the possible role of PCSK9. A single-blinded, placebo-controlled cross-over study using the human endotoxin model was performed. Ten healthy men received lipopolysaccharide (LPS) or placebo on two different study days after overnight fasting. Lipoproteins as well as PCSK9 were measured repetitively over 48 h. PCSK9 plasma concentrations were not induced by LPS infusion, and no correlation between PCSK9 plasma concentrations and the degree of inflammation could be identified. The observed low-density lipoprotein (LDL) response to inflammation was more complex than anticipated, especially in the very early phase after the inflammatory stimulus. Baseline concentrations of LDL, as well as high-density lipoprotein (HDL), correlated negatively with inflammatory response. Our data suggest that the lipoprotein response to inflammation is independent of PCSK9. The proposed elevations of PCSK9 and suspected correlations between PCSK9 levels and inflammatory response are not supported by our data. (This study has been registered at ClinicalTrials.gov under registration no. NCT03392701.).

Comparison between activated clotting time and anti-activated factor X activity for the monitoring of unfractionated heparin therapy in patients with aortic aneurysm undergoing an endovascular procedure.

OBJECTIVE: Current guidelines recommend administration of unfractionated heparin (UFH) and measurement of activated clotting time (ACT) during endovascular procedures. The aim of this study was to compare ACT and anti-activated factor X (anti-Xa) measurements for monitoring of UFH therapy during an aortic endograft procedure and to assess the association of peak ACT and peak anti-Xa activity with periprocedural bleeding. METHODS: We retrospectively studied 104 patients with aortic aneurysm undergoing endovascular procedures with repeated coagulation measurements. After a UFH bolus, further UFH doses were given according to ACT (target range, ≥250 seconds) in clinical routine, and in parallel to each ACT (Hemochron; Accriva Diagnostics, Newport Beach, Calif) measurement, we determined anti-Xa activity (HemosIL Liquid anti-Xa; Instrumentation Laboratory, Bedford, Mass). UFH redosing was solely based on the ACT measurements. We defined periprocedural bleeding as a drop in hemoglobin level ≥3 g/dL or red blood cell transfusion within 24 hours. RESULTS: After the initial UFH bolus (median, 67 IU/kg body weight), ACT and anti-Xa measurements showed a weak correlation (rs, 0.46; P < .001). Median ACT was 233 seconds (range, 127-374 seconds; interquartile range [IQR], 204-257 seconds); median anti-Xa activity was 1.0 IU/mL (range, 0.5-2.0 IU/mL; IQR, 0.9-1.2 IU/mL). Only 31% of the patients had an ACT value ≥250 seconds, whereas all patients had an anti-Xa activity ≥0.5 IU/mL. Accordingly, ACT triggered redosing of UFH frequently. Consequently, we saw a median total UFH use of 90 IU/kg during the procedure, a median peak ACT of 255 seconds (IQR, 234-273 seconds), and a median peak anti-Xa activity of 1.2 IU/mL (IQR, 1.0-1.4 IU/mL). Periprocedural bleeding occurred in 40 (38%) patients. Peak ACT ≥250 seconds was not associated with bleeding (odds ratio, 1.05; 95% confidence interval, 0.41-2.70; P = .952), whereas peak anti-Xa activity ≥1.2 IU/mL was independently associated with bleeding (odds ratio, 4.95; 95% confidence interval, 1.82-13.48; P = .002). Moreover, no periprocedural thromboembolic event occurred. CONCLUSIONS: In this retrospective study of patients with aortic aneurysm undergoing an endovascular procedure, ACT and anti-Xa measurements showed poor correlation; only increased peak anti-Xa activity was independently associated with periprocedural bleeding, not increased ACT. Our findings also suggest that monitoring of UFH therapy with anti-Xa during aortic endograft procedures may reduce total UFH use. We further speculate that this approach could reduce periprocedural bleeding.

Increased serum concentrations of soluble ST2 predict mortality after burn injury.

BACKGROUND: Large burn injuries induce a systemic response in affected patients. Soluble ST2 (sST2) acts as a decoy receptor for interleukin-33 (IL-33) and has immunosuppressive effects. sST2 has been described previously as a prognostic serum marker. Our aim was to evaluate serum concentrations of sST2 and IL-33 after thermal injury and elucidate whether sST2 is associated with mortality in these patients. METHODS: We included 32 burn patients (total body surface area [TBSA] >10%) admitted to our burn intensive care unit and compared them to eight healthy probands. Serum concentrations of sST2 and IL-33 were measured serially using an enzyme-linked immunosorbent assay (ELISA) technique. RESULTS: The mean TBSA was 32.5%±19.6%. Six patients (18.8%) died during the hospital stay. Serum analyses showed significantly increased concentrations of sST2 and reduced concentrations of IL-33 in burn patients compared to healthy controls. In our study cohort, higher serum concentrations of sST2 were a strong independent predictor of mortality. CONCLUSIONS: Burn injuries cause an increment of sST2 serum concentrations with a concomitant reduction of IL-33. Higher concentrations of sST2 are associated with increased in-hospital mortality in burn patients.

[Edoxaban for stroke prevention in atrial fibrillation and treatment of venous thromboembolism: an expert position paper]. / Edoxaban zur Schlaganfallprophylaxe bei Patienten mit nicht-valvulärem Vorhofflimmern und zur Behandlung venöser Thromboembolien: ein interdisziplinäres Positionspapier.

Edoxaban is the most recent available representative of the Non-Vitamin K antagonist oral anticoagulants (NOAC). The approval was based on the largest phase III trials of NOACs for stroke prevention in patients with non-valvular atrial fibrillation (AF, ENGAGE-AF), and for the treatment of venous thromboembolism (VTE, HOKUSAI-VTE). In both trials, edoxaban was associated with similar efficacy and a significant reduction in bleeding events with respect to the pre-defined primary safety endpoints, as compared to warfarin.Additionally, the once daily dosing of edoxaban, the clinically investigated strategy for dose-reduction based on clearly defined criteria and the favorable pharmacokinetic profile might further support the clinical applicability of the substance.In the light of recent data, this expert consensus document aims to summarize the latest clinical trial results while providing a concise overview of current guideline recommendations on the management of patients with non-valvular AF and VTE.

Prognostic Value of Inflammatory and Cardiovascular Biomarkers for Prediction of 90-Day All-Cause Mortality after Acute Ischemic Stroke-Results from the Linz Stroke Unit Study.

BACKGROUND: Early outcome prediction after acute ischemic stroke is of great interest. The aim of our study was to evaluate the prognostic value of blood biomarkers in patients with acute ischemic stroke. METHODS: We measured interleukin-6 (IL-6), d-dimer, amino-terminal pro-B-type natriuretic peptide (NT-proBNP), high-sensitivity cardiac troponin T, and soluble ST2 plasma concentrations within 24 h after admission to our stroke unit in 721 consecutive acute ischemic stroke patients. End point was 90-day all-cause mortality. RESULTS: During follow-up 81 patients died (11%). In univariate Cox proportional hazards regression analyses with the biochemical markers dichotomized according to median values, all baseline blood biomarkers were strong prognostic markers. However, in the multivariate analysis after adjustment for several clinical variables and the NIH Stroke Scale (NIHSS), only NIHSS >3 [risk ratio (RR) 7.87, 95% CI, 3.61-17.16; P < 0.001], IL-6 > 7 pg/mL (RR 4.09, 95% CI, 2.02-8.29; P < 0.001), and NT-proBNP >447 ng/L (RR 4.88, 95% CI, 2.41-9.88; P < 0.001) remained independent predictors. Using a simple multimarker approach combining these 3 complementary markers, we demonstrated that patients with increased NIHSS, IL-6, and NT-proBNP had the poorest outcome with a mortality rate of 38%, whereas no patient with negative readings for all 3 markers died during follow-up. CONCLUSIONS: In this large cohort of patients with acute ischemic stroke, IL-6 and NT-proBNP at admission were strong and independent prognostic markers for 90-day all-cause mortality, and provided complementary prognostic information to the routinely used stroke severity score NIHSS.

Concentrated lyophilized plasma used for reconstitution of whole blood leads to higher coagulation factor activity but unchanged thrombin potential compared with fresh-frozen plasma.

BACKGROUND: During massive hemorrhage, it is recommended to transfuse red blood cells, platelet concentrate, and fresh-frozen plasma in a ratio close to 1:1:1. To avoid the thawing process of fresh frozen plasma, lyophilized plasma (LP) is increasingly used. Evidence is limited on the activity of coagulation factors in reconstituted blood using LP and concentrated LP versions. STUDY DESIGN AND METHODS: Whole blood from ten healthy volunteers was separated into red blood cell, fresh frozen plasma, and platelet concentrate units. Aliquots of red blood cells and plasma concentrate were mixed with either fresh frozen plasma (200 mL) or LP at reconstitution ratios of 2:1:1, 1:1:1, and 1:1:2. LP was used either at the recommended standard volume of 200 mL (LP200) or was more concentrated at volumes of 100 and 50 mL (LP100 and LP50, respectively). The hemostatic capacity of each reconstituted whole blood sample was tested with blood cell counts, standard coagulation tests, factor activity, thrombin generation, and viscoelastic assays. RESULTS: Hematocrit, platelet counts, and fibrinogen levels of the three ratios were similar between FFP200 and LP200 units but were lower compared with the corresponding ratios in LP100 and LP50 units. The activity of procoagulant and anticoagulant factors increased linearly with the increasing plasmatic fraction and, at 1:1:2 ratio, was significantly higher in LP50 units compared with FFP200 and LP200 units. Thrombin generation was similar throughout the four plasma groups at any ratio. CONCLUSIONS: Decreasing the dilution volume of LP facilitates reaching higher hematocrit and coagulation protein levels without a relevant increase in thrombin generation. This is due to preserved balance between procoagulant and anticoagulant factors in the concentrated LP preparations.

Mortality rates at 10 years are higher in diabetic than in non-diabetic patients with chronic lower extremity peripheral arterial disease.

Patients with lower extremity peripheral artery disease (PAD) have a substantially increased risk for mortality as compared to healthy individuals. We aimed to evaluate the risk for all-cause mortality in PAD patients and in healthy controls during a 10-year follow-up period. Our hypothesis was that the mortality rates at 10 years would differ in diabetic and non-diabetic PAD patients. Our study group consisted of 331 consecutive patients with symptomatic PAD <75 years of age admitted to a tertiary care hospital, including 216 patients without diabetes and 115 with diabetes. Control subjects without atherosclerotic disease were matched to the patients in a 1:1 design by sex, age, and diabetes mellitus status. The outcome measure was all-cause mortality at 10 years. Mortality rates at 10 years were 29% in non-diabetic PAD patients versus 14% in age- and sex-matched non-diabetic controls (risk ratio (RR), 2.31; 95% confidence interval (CI), 1.54-3.47; p<0.001), and 58% in diabetic PAD patients versus 19% in age- and sex-matched diabetic controls (RR, 4.06; 95% CI, 2.67-6.18; p<0.001). Further, PAD patients with diabetes had a significantly increased risk for death within 10 years than did the non-diabetic PAD patients (RR, 2.51; 95% CI, 1.72-3.66; p<0.001). Diabetes was independently associated with outcome, and was the strongest predictor of death in multivariate Cox proportional hazards regression. We conclude that mortality rates at 10 years differ in PAD patients <75 years old with and without diabetes. Our findings suggest that future studies should apply distinct risk assessment strategies in the two PAD subgroups.

Increased soluble ST2 predicts long-term mortality in patients with stable coronary artery disease: results from the Ludwigshafen risk and cardiovascular health study.

BACKGROUND: Soluble suppression of tumorigenicity 2 (sST2) has emerged as a strong prognostic biomarker in patients with heart failure and myocardial infarction. The aim of this study was to evaluate the long-term prognostic value of sST2 in patients with stable coronary artery disease (CAD). METHODS: sST2 plasma concentrations were measured in 1345 patients with stable CAD referred for coronary angiography at a single tertiary care center. The primary endpoint was all-cause mortality. RESULTS: During a median follow-up time of 9.8 years, 477 (36%) patients died. The median sST2 plasma concentration at baseline was significantly higher among decedents than survivors (21.4 vs 18.5 ng/mL; P < 0.001). In multivariate Cox proportional hazards regression analysis, sST2 was an independent predictor of all-cause mortality (risk ratio 1.16 per 1-SD increase in log-transformed values; 95% CI 1.05-1.29; P = 0.004). In the same multivariate analysis, amino-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity cardiac troponin T (hs-cTnT) were also independent predictors, whereas galectin-3 was not. Patients with sST2 in the highest quartile (>24.6 ng/mL) displayed a 2-fold increased risk of death in univariate analysis, which was attenuated but remained significant in a fully adjusted model (risk ratio 1.39; 95% CI 1.10-1.76; P = 0.006). Further analysis showed that the prognostic impact of sST2 was additive to NT-proBNP and hs-cTnT. Using a multibiomarker approach combining these 3 complementary makers, we demonstrated that patients with all 3 biomarkers in the highest quartiles had the poorest outcome. CONCLUSIONS: In this cohort of patients with stable CAD, increased sST2 was an independent predictor of long-term all-cause mortality and provided complementary prognostic information to hs-cTnT and NT-proBNP.

Mortality rates and mortality predictors in patients with symptomatic peripheral artery disease stratified according to age and diabetes.

OBJECTIVE: Atherosclerotic peripheral arterial disease (PAD) is one of the most prevalent, morbid, and mortal diseases. The aim of this study was to evaluate mortality rates of patients with atherosclerotic PAD stratified according to age and diabetes and to determine predictors of death. METHODS: We studied 487 patients with symptomatic PAD consecutively admitted to the hospital. This cohort included the following four patient subgroups: (1) 216 patients with PAD <75 years of age without diabetes mellitus; (2) 115 patients with PAD < 75 years of age with diabetes mellitus; (3) 102 patients with PAD ≥ 75 years of age without diabetes mellitus; and (4) 54 patients with PAD ≥ 75 years of age with diabetes mellitus. Control subjects without atherosclerotic disease were matched to the patients with PAD in a 1:1 design by sex, age (± 2 years), and diabetes mellitus status. Outcome measure was all-cause mortality at 5 years. RESULTS: Mortality rates at 5 years were 10% in nondiabetic patients with PAD < 75 years of age (vs 5% in control subjects; risk ratio [RR], 2.15; 95% confidence interval [CI], 1.60-4.34); 23% in diabetic patients with PAD < 75 years of age (vs 7% in control subjects; RR, 3.53; 95% CI, 1.80-6.91); 38% in nondiabetic patients with PAD ≥ 75 years of age (vs 22% in control subjects; RR, 2.08; 95% CI, 1.26-3.44); and 52% in diabetic patients with PAD ≥ 75 years of age. Applying multivariate Cox proportional hazards regression analyses (with cardiovascular risk factors, coexisting atherosclerotic disease, clinical stage of PAD, and several biochemical markers as predictor variables), we found the following independent predictors of outcome: in the 216 nondiabetic patients with PAD < 75 years of age, high-sensitivity C-reactive protein (hs-CRP) (RR, 3.04; 95% CI, 1.48-6.26); in the 115 diabetic patients with PAD < 75 years of age, amino-terminal pro-B-type natriuretic peptide (NT-proBNP) (RR, 2.63; 95% CI, 1.65-4.19); in the 102 nondiabetic patients with PAD ≥ 75 years of age, critical limb ischemia (RR, 3.70; 95% CI, 1.82-7.52) and NT-proBNP (RR, 1.93; 95% CI, 1.32-2.82); and in the 54 diabetic patients with PAD ≥ 75 years of age, hs-CRP (RR, 2.61; 95% CI, 1.45-4.67) and NT-proBNP (RR, 3.31; 95% CI, 1.96-5.60). CONCLUSIONS: Mortality rates at 5 years varied considerably among patients with PAD stratified according to age and diabetes. Predictors of death differed among the four patient subgroups in this study and included critical limb ischemia, hs-CRP, and NT-proBNP. Our results might help to develop future strategies for optimized treatment of hospitalized patients with symptomatic PAD.

A variant associated with nicotine dependence, lung cancer and peripheral arterial disease.

Smoking is a leading cause of preventable death, causing about 5 million premature deaths worldwide each year. Evidence for genetic influence on smoking behaviour and nicotine dependence (ND) has prompted a search for susceptibility genes. Furthermore, assessing the impact of sequence variants on smoking-related diseases is important to public health. Smoking is the major risk factor for lung cancer (LC) and is one of the main risk factors for peripheral arterial disease (PAD). Here we identify a common variant in the nicotinic acetylcholine receptor gene cluster on chromosome 15q24 with an effect on smoking quantity, ND and the risk of two smoking-related diseases in populations of European descent. The variant has an effect on the number of cigarettes smoked per day in our sample of smokers. The same variant was associated with ND in a previous genome-wide association study that used low-quantity smokers as controls, and with a similar approach we observe a highly significant association with ND. A comparison of cases of LC and PAD with population controls each showed that the variant confers risk of LC and PAD. The findings provide a case study of a gene-environment interaction, highlighting the role of nicotine addiction in the pathology of other serious diseases.

Circulating heat shock protein 27 as a biomarker for the differentiation of patients with lung cancer and healthy controls--a clinical comparison of different enzyme linked immunosorbent assays.

BACKGROUND: Increased heat shock protein 27 (HSP27) has been described in patients with non-small cell lung cancer (NSCLC). The aim of this study was to evaluate five commercially available assays for HSP27 measurement with respect to their capabilities to differentiate NSCLC patients from healthy controls. METHODS: We measured HSP27 serum concentrations in 40 NSCLC cases and 40 healthy controls by different assays (i.e., R&D, Enzo Life Sciences, Invitrogen, Abcam, and MyBioSource). We analyzed receiver operating characteristic plots and calculated areas under the curve (AUCs) for the five HSP27 assays with the case-control status as the classification variable. RESULTS: The following AUCs were obtained: R&D, 0.834 (95% CI, 0.734 - 0.908); Enzo Life Sciences, 0.823 (95% CI, 0.722 - 0.899); Invitrogen, 0.780 (95% CI, 0.674 - 0.856); Abcam, 0.642 (95% CI, 0.528 - 0.747); and MyBioSource 0.523 (95% CI, 0.408 - 0.636). An explorative comparison of the AUCs revealed that the R&D, Enzo Life Sciences, and Invitrogen assays perform better than the Abcam and MyBioSource assays in the setting evaluated. Results obtained by different HSP27 assays had up to 10-fold difference of serum concentrations, and correlation coefficients of pairwise assay comparisons ranged from 0.184 - 0.938. CONCLUSIONS: The results of our clinical method comparison study revealed that commercially available HSP27 assays are not equally useful to differentiate NSCLC patients from healthy controls. Our study suggests that certain HSP27 methods cannot be applied for diagnostic purposes in lung cancer and probably also not in other diseases.

Association of serum zinc with mineral stress in chronic kidney disease.

Background: The excessive cardiovascular mortality of patients with chronic kidney disease (CKD) could be linked to mineral stress, the biological consequence of calcium-phosphate nanoparticle exposure. This study investigated whether zinc is associated with mineral stress markers in CKD. Methods: Zinc and T50 (serum calcification propensity) as well as hydrodynamic radius of secondary calciprotein particles (CPP2) were measured in blood donors and CKD patients with/out dialysis. Results: Serum zinc concentrations and T50 were reduced, while CPP2 radius was increased in CKD patients. Serum zinc levels positively correlated with T50 and inversely correlated with CPP2 radius. In a hierarchical linear regression model, T50 was associated with age, calcium, phosphate, magnesium and albumin. Addition of zinc significantly improved prediction of the model, confirming an additional contribution of zinc to T50. Similar observations were made for the association of zinc and CPP2 radius, but spiking experiments indicated that zinc may stronger modify T50 than CPP2 radius. Also, urinary zinc excretion was increased in patients with kidney disease and correlated to T50 and CPP2 radius. Serum zinc further correlated with markers of arterial stiffness in blood donors and CKD patients, but these associations did not remain significant in a multivariate linear regression model. Conclusions: Reduced serum zinc levels in CKD appear directly linked to lower T50 and associated with larger CPP2 radius. Further studies on the associations of zinc and mineral stress as well as putative therapeutic benefits of zinc supplementation are required.

Immunogenicity Parameters of Cancer Patients Receiving the mRNA Vaccine BNT162b2 While Obtaining Radiotherapy: A Longitudinal Cohort Evaluation.

BACKGROUND: Cancer patients are highly prone to infectious diseases. While undergoing antineoplastic treatment, the risk of severe symptoms upon infection increases, necessitating efficient protective measures, such as vaccination. For patients receiving radiotherapy, there is no specific information about humoral immunity. During the COVID-19 pandemic, serial antibody measurements were therefore offered to cancer patients, following SARS-CoV-2 vaccination while obtaining radiotherapy. METHODS: Out of 74 enrolled patients, 46 met the inclusion criteria. Two cohorts were allocated, depending on an association with chemotherapy or pure radiotherapy. An additional healthy control cohort of 16 healthcare workers was enrolled. All participants followed a two-fold BNT162b2 vaccine schedule. SARS-CoV-2 binding antibodies were measured serially in a 7-day cycle for 35 days and over the long-term, using the Elecsys® Anti-SARS-CoV-2 immunoassay. RESULTS: Cancer patients under pure radiotherapy have a comparable humoral vaccination response and long-term persistency of antibodies to healthy controls. Patients receiving additional chemotherapy show a significantly delayed immune response and decreased antibody titers. The vaccine was well tolerated in all cohorts. CONCLUSIONS: Pure radiotherapy in cancer patients does not interfere with the vaccine-induced humoral immune response or other immunogenetic aspects, whereas previous or simultaneous chemotherapy does. Findings are of particular relevance for future epidemic or pandemic scenarios.