Markers of cardiac injury in patients with liver cirrhosis.

Liver cirrhosis is an increasing public health problem and a major cause of morbidity and mortality. Accordingly, cirrhotic cardiomyopathy, a frequently underdiagnosed condition, is becoming a growing health problem. In the last 20 years, cardioselective biomarkers have been investigated for their diagnostic and prognostic properties for numerous conditions. The aim of this article is to review the literature on the relationship between the most commonly used cardioselective biomarkers (cardiac troponins I and T, N-terminal pro-B-type natriuretic peptide, brain natriuretic peptide, and heart-type fatty-acid binding protein) and the presence, functional stage, and clinical outcomes of liver cirrhosis. Elevated plasma levels of these biomarkers have been reported in patients with liver cirrhosis, and there is mounting evidence on their predictive value for clinical outcomes in this disease. In addition, elevated plasma levels of these biomarkers have been reported in patients before, during, and after liver transplantation, but in fewer studies. Due to their predictive value for clinical outcomes, we advocate the use of these markers in patients with liver cirrhosis and cirrhotic cardiomyopathy, as well as in candidates for liver transplant.

Effects of recreational scuba diving on erythropoiesis-"normobaric oxygen paradox" or "plasma volume regulation" as a trigger for erythropoietin?

PURPOSE: Previous studies have shown an increase in erythrocyte lipid peroxidation and a decrease in red blood cell (RBC) count, hemoglobin, and hematocrit after only one recreational scuba diving session. The aim of this study was to examine the effect of repetitive scuba diving on RBC parameters and erythropoiesis. METHODS: Divers (N = 14) conducted one dive per week over 5 weeks at a depth of 20-30 m for 30 min. For measuring RBC parameters, erythropoietin, iron, and ferritin, blood samples were collected before and after the first, third, and fifth dive. RESULTS: Between pre- and post-dive results, a statistically significant increase in RBC count, hemoglobin, hematocrit, mean corpuscular volume (MCV), RBC distribution width (RDW), iron, and ferritin was observed. Analysis of the results between the first, third, and fifth dive showed that the erythropoietin increase at the third (pre-dive p = 0.009; post-dive p = 0.004) and fifth dive (pre-dive p < 0.001; post-dive p = 0.003) was not accompanied by changes in RBC count, hemoglobin, iron, and ferritin. In parallel, a continuous increase in hematocrit, MCV, and RDW was observed, whereas mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) decreased. CONCLUSIONS: Changes in RBC indices and EPO elevation indicate that the occasional switch from hyperoxia to normoxia or mechanisms for plasma volume regulation may be a step in the maintenance of erythropoiesis.

Galectin-3 and Cardiovascular Biomarkers Reflect Adaptation Response to Scuba Diving.

To understand better the adaptation response of the cardiovascular system (CVS) to self-contained underwater breathing apparatus (SCUBA) diving, Galectin-3 (Gal-3) and specific CVS biomarkers were measured in plasma of 16 male recreational divers before and after (30 min, 3 and 6 h) diving (total time of 30 min at 30 m depth) undertaken a after long non-dive period. The one-time SCUBA dive caused a significant increase in Gal-3, N-terminal prohormone of brain natriuretic peptide (NT-proBNP), high-sensitivity troponin-I (hs-TnI), and myoglobin immediately after diving. Whereas Gal-3 and myoglobin dropped down to the basal levels during the recovery period, NT-proBNP and hs-TnI concentration continued to increase. An immediate increase of vascular endothelial growth factor, detected immediately after diving, was followed by a significant decrease and return to the basal level, 3 and 6 h after diving, respectively. After a significant initial decrease, endothelin-1 increased during the recovery period, but did not return to the basal level. The observed changes in these biomarkers reflect comprehensive, but transient adaptation of CVS and muscular system to the specific environmental conditions during the SCUBA dive. Whether the recurrent activation of these adaption mechanisms due to repetitive dives has positive or negative effects on CVS remains to be elucidated.

Nutritional Status of Patients with Chronic Obstructive Pulmonary Disease in Relation to their Physical Performance.

Nutritional abnormalities and physical inactivity are highly prevalent in patients with chronic obstructive pulmonary disease (COPD). The aim of this study was to determine the association between nutritional status/body composition and physical performance in patients with COPD. A cross-sectional observational study was conducted in outpatients with clinically stable, moderate to very severe COPD. In the assessment of nutritional status, we used dual energy X-ray absorptiometry, anthropometry, serum biomarkers, and the Mini-Nutritional Assessment (MNA) questionnaire. Physical performance was measured by the 6-minute walk distance (6MWD), 4-metre gait speed (4MGS), and physical activity. Univariate and multivariate analyses were performed. In 111 patients (mean age 68 years, 69% men), the mean 6MWD was 376 ± 119 m, 4MGS 0.9 ± 0.2 m/s, and the average daily step count 8,059 ± 4,757. Patients with low exercise capacity (6MWD ≤ 350 m) had a significantly lower lean mass index (LMI) (p < 0.01), fat-free mass index (FFMI) (p < 0.01), bone mineral content (p < 0.01), bone mineral density (p < 0.01), T-score (p < 0.05), MNA score (p < 0.01), and serum albumin and prealbumin levels (p < 0.05). Patients with low physical activity (daily step count ≤ median) had lower LMI, FFMI, MNA score, serum prealbumin (for all comparisons p < 0.05) and vitamin D levels (p < 0.01). However, none of the nutritional variables showed an independent association with low physical performance in the multivariate models. In conclusion, patients with low physical performance have deficient nutritional status, but we could not demonstrate an independent relationship between nutritional parameters and physical performance.

Neutrophil-to-lymphocyte and platelet-to-lymphocyte ratio help identify patients with lung cancer, but do not differentiate between lung cancer subtypes.

AIM: To assess the diagnostic value of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in lung cancer (LC). We compared the ratios between healthy participants and all LC patients, as well patients with different pathohistological LC subtypes. METHODS: We retrieved the data on neutrophil, lymphocyte, and platelet levels in 449 patients with different pathohistological LC subtypes (non-small cell LC, small-cell LC, atypical or metastatic LC, neuroendocrine, and sarcomatoid carcinoma) and 47 healthy controls. NLR and PLR were calculated by dividing the absolute number of neutrophils or platelets with the absolute number of lymphocytes. RESULTS: There were significant differences in both NLR and PLR (P<0.001) between all LC patients and the control group, but there were no differences between patients with different LC subtypes. Reciever operating characteristics analysis for NLR showed the optimal cut-off value of 2.71, with a sensitivity of 77.05% and specificity of 87.23%. The optimal cut-off value for PLR was 182.31, with a sensitivity of 51.09% and specificity of 91.49%. CONCLUSION: The results showed that the NLR and PLR may have added value in the early diagnosis of LC, but further research is needed to confirm these results.

Serum proteomic profiling of patients with compensated advanced chronic liver disease with and without clinically significant portal hypertension.

INTRODUCTION: Portal hypertension (PH) drives the progression of liver cirrhosis to decompensation and death. Hepatic venous pressure gradient (HVPG) measurement is the standard of PH quantification, and HVPG≥10 mmHg defines clinically significant PH (CSPH). We performed proteomics-based serum profiling to search for a proteomic signature of CSPH in patients with compensated advanced chronic liver disease (cACLD). MATERIALS AND METHODS: Consecutive patients with histologically confirmed cACLD and results of HVPG measurements were prospectively included. Serum samples were pooled according to the presence/absence of CSPH and analysed by liquid chromatography-mass spectrometry. Gene set enrichment analysis was performed, followed by comprehensive literature review for proteins identified with the most striking difference between the groups. RESULTS: We included 48 patients (30 with, and 18 without CSPH). Protein CD44, involved in the inflammatory response, vascular endothelial growth factor C (VEGF-C) and lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1), both involved in lymphangiogenesis were found solely in the CSPH group. Although identified in both groups, proteins involved in neutrophil extracellular traps (NET) formation, as well as tenascin C, autotaxin and nephronectin which mediate vascular contractility and lymphangiogenesis were more abundant in CSPH. DISCUSSION AND CONCLUSION: We propose that altered inflammatory response, including NET formation, vascular contractility and formation of new lymph vessels are key steps in PH development. Proteins such as CD44, VEGF-C, LYVE-1, tenascin C, Plasminogen activator inhibitor 1, Nephronectin, Bactericidal permeability-increasing protein, Autotaxin, Myeloperoxidase and a disintegrin and metalloproteinase with thrombospondin motifs-like protein 4 might be considered for further validation as potential therapeutic targets and candidate biomarkers of CSPH in cACLD.

Laboratory medicine and sports: where are we now?

Laboratory medicine in sport and exercise has significantly developed during the last decades with the awareness that physical activity contributes to improved health status, and is present in monitoring both professional and recreational athletes. Training and competitions can modify concentrations of a variety of laboratory parameters, so the accurate laboratory data interpretation includes controlled and known preanalytical and analytical variables to prevent misleading interpretations. The paper represents a comprehensive summary of the lectures presented during the 35th Annual Symposium of the Croatian Society of Medical Biochemistry and Laboratory Medicine. It describes management of frequent sport injuries and sums up current knowledge of selected areas in laboratory medicine and sports including biological variation, changes in biochemical parameters and glycemic status. Additionally, the paper polemicizes sex hormone disorders in sports, encourages and comments research in recreational sports and laboratory medicine. In order to give the wider view, the connection of legal training protocols as well as monitoring prohibited substances in training is also considered through the eyes of laboratory medicine.

Low Level of First Morning Urine Cardiac Troponin I: A Specific Hallmark of Aortic Stenosis Severity.

Background: It has recently been shown that cardiac-specific troponin I concentrations in first morning urine samples can be measured with commercially available tests. Due to their accumulation in the first morning urine, scientific papers indicate a potential predictive value for cardiovascular diseases. Therefore, the aim of this study was to compare the concentration of cardiac troponin I in the first morning urine in patients with severe aortic stenosis and the healthy population. Patients and Methods: Blood and first morning urine samples were collected from 34 healthy individuals (17 female) at University Hospital Merkur and 25 patients with severe aortic stenosis (14 female) before surgical treatment at University Hospital Dubrava. Cardiac troponin I and T values were determined using high-sensitivity assays using commercially available Abbott and Roche tests. Results: Patients with severe aortic stenosis had significantly lower troponin I concentrations in the first morning urine samples (0.3 ng/L (0.1-0.6)) as compared to the healthy population (15.2 ng/L (8.4-19.9)) (p < 0.001). There was no statistically significant difference in troponin T concentrations between healthy individuals and patients with severe aortic stenosis. In parallel, both I and T plasma troponin concentrations were significantly higher in patients with severe aortic stenosis. Conclusions: In patients with severe aortic stenosis, cardiac troponin I values in the first morning urine are significantly lower than in healthy subjects.

Glycemia and Coagulation in Patients with Glioblastomas.

BACKGROUND: Glioblastomas are among the most malignant tumors which, despite aggressive treatment, currently have an abysmal prognosis. These lesions are known to cause local and systemic perturbations in the coagulation system, leading to neoangiogenesis and a high risk of venous thromboembolism. Indeed, there have been multiple proposals of the coagulation system being a possible target for future treatment of these patients. However, nonselective anticoagulant therapy has proven suboptimal and leads to a significant increase of intracranial hemorrhage. Thus, recognizing factors that lead to hypercoagulation is considered paramount. Hyperglycemia is a well-known prothrombotic factor, a fact that has received little attention in neuro-oncology. We previously hypothesized that patients with brain tumors could be highly susceptible to iatrogenic glycemia dysregulation. Here, we analyzed the connection between glycated hemoglobin (HbA1c) and the routine coagulation markers (D-dimers, prothrombin time and activated partial thromboplastin time [aPTT]) in patients with de novo intracranial glioblastomas. METHODS: Included in this study were 74 patients who were operated on in 2 hospitals: Clinical Hospital Dubrava, Zagreb, Croatia; University Hospital Center Split, Split, Croatia; and University Hospital de la Princesa, Madrid, Spain. RESULTS: We found a significant inverse correlation between HbA1c and aPTT (ρ = -0.379; P = 0.0009). We also found a significant inverse correlation between Ki67 immunoreactivity and aPTT (ρ = -0.211; P = 0.0082). No connection was found between HbA1c and D-dimers or prothrombin time. CONCLUSIONS: Our results suggest that patients with hyperglycemia, with a more proliferative glioblastoma, could in fact have their coagulation profile significantly disrupted, primarily through the intrinsic coagulation pathway. Such findings could have great clinical importance. Further research in this area could help to elucidate the vicious connection between glioblastomas and coagulation and to combat this deadly disease.

Effects of recreational SCUBA diving practiced once a week on neurohormonal response and myokines-mediated communication between muscles and the brain.

Objective: During physical activity, activation of muscular, endocrine, and nervous systems, results in intensive crosstalk between muscles and other organs, which enables response to physiological stress. In SCUBA diving, extreme environmental conditions represent an additional challenge for homeostasis maintenance, but underlying mechanisms are largely unknown. We aimed to contribute to the understanding of neurohormonal response and muscle-brain crosstalk by measuring the concentrations of the selected hormones secreted by the pituitary-target organ axis and myokines involved in the muscle-brain endocrine loop in recreational SCUBA (rSCUBA) divers. Methods: Fourteen male divers performed five open-water recreational dives (one per week, depth of 20-30 m, lasting 30 min, between 9 and 10 am), after a winter non-diving period of 5 months. Blood samples were collected immediately before and after the first, third, and fifth dives. Adrenocorticotropic hormone (ACTH), cortisol, thyroid-stimulating hormone (TSH), free thyroxine (fT4), prolactin, total testosterone, growth hormone (GH), insulin-like growth factor-1 (IGF-1), irisin, brain-derived neurotrophic factor (BDNF), S100B, glial fibrillary acidic protein (GFAP), and neuron-specific enolase (NSE) were measured using commercially available immunoassays. Results: Cortisol and ACTH levels decreased after every dive, while total testosterone decreased only after the first dive. No significant changes in post-dive values, as well as the cumulative effect on any other measured hormone, were observed. Although irisin and BDNF levels decreased after the first and third dives, the fifth dive caused a significant increase in both myokines. Changes in IGF-1 levels were not observed. All three dives caused a significant increase in S100B levels. A statistically significant decrease in GFAP concentration was observed after every dive, while NSE pre-dive concentration declined over the studied period. The cumulative effect on myokine levels was reflected in a continuous decline in irisin and BDNF pre-dive levels throughout the studied period, but an increasing trend after the fifth dive was observed. Conclusions: Observed changes in myokines and hormone levels point to a specific response to rSCUBA practiced once a week, most likely due to extreme environmental conditions. Further studies on communication between muscles and other organ systems, particularly on the muscle-brain endocrine loop, are required for a deeper understanding of the adaptation mechanisms to this kind of physiological stress.

Changes in Specific Biomarkers Indicate Cardiac Adaptive and Anti-inflammatory Response of Repeated Recreational SCUBA Diving.

Objective: Recreational SCUBA (rSCUBA) diving has become a highly popular and widespread sport. Yet, information on molecular events underlying (patho)physiological events that follow exposure to the specific environmental conditions (hyperbaric conditions, coldness, immersion, and elevated breathing pressure), in which rSCUBA diving is performed, remain largely unknown. Our previous study suggested that repeated rSCUBA diving triggers an adaptive response of cardiovascular and immune system. To elucidate further molecular events underlying cardiac and immune system adaptation and to exclude possible adverse effects we measured blood levels of specific cardiac and inflammation markers. Methods: This longitudinal intervention study included fourteen recreational divers who performed five dives, one per week, on the depth 20-30 m that lasted 30 min, after the non-dive period of 5 months. Blood samples were taken immediately before and after the first, third, and fifth dives. Copeptin, immunoglobulins A, G and M, complement components C3 and C4, and differential blood count parameters, including neutrophil-to-lymphocyte ratio (NLR) were determined using standard laboratory methods. Cell-free DNA was measured by qPCR analysis and N-glycans released from IgG and total plasma proteins (TPP), were analyzed by hydrophilic interaction ultra-performance liquid chromatography. Results: Copeptin level increased after the first dive but decreased after the third and fifth dive. Increases in immunoglobulins level after every dive and during whole studied period were observed, but no changes in C3, C4, and cfDNA level were detected. NLR increased only after the first dive. IgG and TPP N-glycosylation alterations toward anti-inflammatory status over whole studied period were manifested as an increase in monogalyctosylated and core-fucosylated IgG N-glycans and decrease in agalactosylated TPP N-glycans. Conclusion: rSCUBA diving practiced on a regular basis promotes anti-inflammatory status thus contributing cardioprotection and conferring multiple health benefits.

Adaptive response triggered by the repeated SCUBA diving is reflected in cardiovascular, muscular, and immune biomarkers.

It has been shown that one recreational SCUBA (rSCUBA) diving session is sufficient to cause changes in plasma level of cardiovascular (CV) and muscular biomarkers. To explore whether repetitive rSCUBA diving triggers an adaptive response of the CV, muscular, and immune system, we measured the cardiac damage (NT-proBNP, hs-TnI, and CK-MB), muscle damage (myoglobin (Mb), galectin-3, CK, and LDH), vascular endothelial activation (ET-1 and VEGF), and inflammatory (leukocyte count (Lkc), CRP, and IL-6) biomarkers. A longitudinal intervention study included divers (N = 14) who conducted one dive per week over 5 weeks at the depth of 20-30 m for 30 min after a non-dive period of 5 months. The blood samples were collected before and after the first, third, and fifth dives and specific biomarkers were measured in plasma or serum by the standard laboratory methods. The concentrations of the majority of measured biomarkers increased after every single dive; the exception was ET-1 concentration that decreased. The cumulative effect of five dives has been reflected in diminishing changes in hs-TnI, Mb, galectin-3, ET-1, VEGF, and IL-6 levels, and more pronounced increases in NT-proBNP and hs-CRP levels. The median values of all measured biomarkers in all time points, except Mb, remained within the corresponding reference range. Repeatedly performed rSCUBA diving activates an adaptive response of the CV, muscular, and immune system that is reflected in changes in the specific biomarker concentration.

Comparison of diagnostic accuracy for eight SARS-CoV-2 serological assays.

INTRODUCTION: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serological tests have been suggested as an additional diagnostic tool in highly suspected cases with a negative molecular test and determination of seroprevalence in population. We compared the diagnostic performance of eight commercial serological assays for IgA, IgM, and IgG antibodies to the SARS-CoV-2 virus. MATERIALS AND METHODS: The comparison study was performed on a total of 76 serum samples: 30 SARS-CoV-2 polymerase chain reaction (PCR)-negative and 46 SARS-CoV-2 PCR-positive patients with asymptomatic to severe disease and symptoms duration from 3-30 days. The study included: three rapid lateral flow immunochromatographic assays (LFIC), two enzyme-linked immunosorbent assays (ELISA), and three chemiluminescence immunoassays (CLIA). RESULTS: Agreement between IgM assays were minimal to moderate (kappa 0.26 to 0.63) and for IgG moderate to excellent (kappa 0.72 to 0.92). Sensitivities improved with > 10 days of symptoms and were: 30% to 89% for IgM; 89% to 100% for IgG; 96% for IgA; 100% for IgA/IgM combination; 96% for total antibodies. Overall specificities were: 90% to 100% for IgM; 85% to 100% for IgG; 90% for IgA; 70% for IgA/IgM combination; 100% for total antibodies. Diagnostic accuracy for IgG ELISA and CIA assays were excellent (AUC ≥ 0.90), without significant difference. IgA showed significantly better diagnostic accuracy than IgM (P < 0.001). CONCLUSION: There is high variability between IgM assays independently of the assay format, while IgG assays showed moderate to perfect agreement. The appropriate time for testing is crucial for the proper immunity investigation.

Easy to Perform Physical Performance Tests to Identify COPD Patients with Low Physical Activity in Clinical Practice.

Background: The study investigates which physical performance or muscle function/mass tests significantly correlate with objectively measured physical activity (PA) in patients with chronic obstructive pulmonary disease (COPD) and could potentially serve to identify physically inactive COPD patients in routine clinical practice. Methods: A cross-sectional, observational study was conducted in outpatients with moderate to very severe COPD. PA was measured during one week with the StepWatch Activity Monitor®, an ankle-worn accelerometer, and expressed in steps per day. Physical fitness and peripheral muscle function/mass were evaluated by the 4-meter gait speed (4MGS) test, the 6-minute walk distance (6MWD), the 30-second chair stand test (30sCST), the timed up and go test (TUGT), handgrip strength, arm muscle area, calf circumference, the fat-free mass index (FFMI), and ultrasound measurement of the quadriceps muscle. Spearman's rank correlation analysis and ROC analysis were performed. Results: The study population (N=111, 69% men, mean age 68 years) walked a mean of 8059 steps/day. The daily step count strongly correlated with the 6MWD (rho=0.684, p<0.001) and moderately with the 4MGS (rho=0.464, p<0.001), the TUGT (rho= -0.463, p<0.001), and the 30sCST (rho=0.402, p<0.001). The correlation with the FFMI was weak (rho=0.210, p=0.027), while the other parameters did not significantly correlate with the daily step count. The 6MWD had the best discriminative power to identify patients with very low PA defined as <5000 steps/day (AUC=0.802 [95% CI: 0.720-0.884], p<0.001), followed by the TUGT, the 4MGS, and the 30sCST. Conclusion: The 6MWD, the 4MGS, the TUGT, and the 30sCST are easy to perform in any clinical setting and may be used by clinicians in the screening of physically inactive COPD patients.