Zeljko Debeljak

• Professor
• Laboratory Manager at University Hospital Centre Osijek

Highlights • In pneumonia and chronic obstructive pulmonary disease (COPD), median pro-gastrin-releasing peptide (proGRP) > 50 ng/L was measured • Median proGRP < 40 ng/L was measured in the early-stage lung adenocarcinoma and squamous cell carcinoma • Pneumonia and COPD patients may have higher proGRP cut-offs compared to small-cell lung cancer

Introduction: Higher concentrations of the small-cell lung cancer (SCLC) serum marker, pro-gastrin-releasing peptide (proGRP), in lung inflammations has been indicated in literature. The objective of this study was to compare serum proGRP concentration in pneumonia, chronic obstructive pulmonary disease (COPD) and early-stage primary lung cancers....

This paper explores the physiological consequences of decreased expression of GD3 synthase (GD3S), a biosynthetic enzyme that catalyzes the synthesis of b-series gangliosides. GD3S is a key factor in tumorigenesis, with overexpression enhancing tumor growth, proliferation, and metastasis in various cancers. Hence, inhibiting GD3S activity has poten...

Background As the healthcare sector evolves, Artificial Intelligence’s (AI’s) potential to enhance laboratory medicine is increasingly recognized. However, the adoption rates and attitudes towards AI across European laboratories have not been comprehensively analyzed. This study aims to fill this gap by surveying European laboratory professionals t...

In the last decades, clinical laboratories have significantly advanced their technological capabilities, through the use of interconnected systems and advanced software. Laboratory Information Systems (LIS), introduced in the 1970s, have transformed into sophisticated information technology (IT) components that integrate with various digital tools,...

During the COVID-19 pandemic, changes occurred within the surgical patient population. An increase in the frequency of resistant Gram-negative bacteria has since been recorded worldwide. After the start of the COVID-19 pandemic, microbiological diagnostics in our institution was performed using MALDI-TOF mass spectrometry. With this study, we wante...

Objective High salt (HS) diet impairs endothelium-dependent vasodilation in many vascular beds, including cerebral microcirculation, and may affect vascular resistance. The aim of present study was to determine if 7-day HS diet affected cerebral and system hemodynamics in response to breath holding test (BHT) and hyperventilation in healthy young p...

Nanotechnology has the potential to provide formulations of antitumor agents with increased selectivity towards cancer tissue thereby decreasing systemic toxicity. This in vivo study evaluated the potential of novel nanoformulation...

Simple Summary Lung cancer is a leading cause of cancer-related deaths worldwide, characterized as a disease usually diagnosed in the advanced stages with limited therapeutic options. Significant progress in the treatment of lung cancer has been achieved by the application of targeted therapy and immunotherapy based on the identification of molecul...

This chapter provides a general overview of metabolic reactions and their significance. Basic concepts and terminology related to biotransformation, activity, and toxicity are explained and discussed. Major enzymes involved in oxidation, reduction, hydrolytic, and conjugation are covered including enzyme nomenclature, localization, catalytic cycle,...

Aim/Introduction The study aimed to determine the effectiveness of early antidiabetic therapy in reversing metabolic changes caused by high-fat and high-sucrose diet (HFHSD) in both sexes. Methods Elderly Sprague–Dawley rats, 45 weeks old, were randomized into four groups: a control group fed on the standard diet (STD), one group fed the HFHSD, an...

[This corrects the article DOI: 10.3389/fphar.2021.656748.].

Carbohydrate sulfotransferases (CHST) catalyse the biosynthesis of proteoglycans that enable physical interactions and signalling between different neighbouring cells in physiological and pathological states. The study aim was to provide an overview of emerging diagnostic and prognostic applications of CHST. PubMed database search was conducted usi...

Aim To determine the most common indications for measuring metanephrine and normetanephrine in plasma by gender and age and to compare the concentrations of metanephrine and normetanephrine by indication, gender and age. Methods The study was conducted on 224 patients whose plasma metanephrine and normetanephrine concentrations were measured at t...

Sucralose is widely used as a non-nutritive sweetener (NNS). However, in order to justify its use as a non-nutritive food additive, sucralose would have to be metabolically neutral. The aim of this study was to examine whether sucralose altered the insulin signaling pathway in an in vitro cell model of Parkinson’s disease (PD)—the dopaminergic diff...

Background: Neopterin is a pteridine produced by mononuclear blood cells after interferon γ stimulation in inflammatory and immune-mediated disorders. The aim of the study is to record the spatial distribution of the neopterin-specific signal with sufficient sensitivity and to use it to determine the number of stimulated mononuclear blood cells.

Background: Matrix assisted laser desorption/ionization time-of-flight mass spectrometry imaging (MALDI TOF MSI) of a single cell, also called microscopic mass spectrometry, enables in situ assessment of the white blood cell (WBC) metabolite's spatial distribution. The aim of this study was to develop blood smear preparation procedures that improve...

Objectives ChatGPT, a tool based on natural language processing (NLP), is on everyone’s mind, and several potential applications in healthcare have been already proposed. However, since the ability of this tool to interpret laboratory test results has not yet been tested, the EFLM Working group on Artificial Intelligence (WG-AI) has set itself the...

Glioblastoma (GBM) is the most common malignancy of the brain with a relatively short median survival and high mortality. Advanced age, high socioeconomic status, exposure to ionizing radiation, and other factors have been correlated with an increased incidence of GBM, while female sex hormones, history of allergies, and frequent use of specific dr...

Cerebral blood flow autoregulation protects brain tissue from blood pressure variations and maintains cerebral perfusion pressure by changes in vascular resistance. High salt (HS) diet impairs endothelium-dependent vasodilation in many vascular beds, including cerebral microcirculation, and may affect vascular resistance. The aim of present study w...

Aim: This study aimed to evaluate serum levels of 25-OH D3 (calcidiol) among students of the Faculty of Medicine Osijek, Croatia, thereby determining to what extent vitamin D deficiency is present. Methods: The present cross-sectional analysis was based on data collected from 60 participants. Blood sampling was done in March 2021. Concentrations of...

Acetyl‐CoA transporter 1 (AT‐1) is a transmembrane protein which regulates influx of acetyl‐CoA from the cytosol to the lumen of the endoplasmic reticulum and is therefore important for the posttranslational modification of numerous proteins. Pathological variants in the SLC33A1 gene coding for AT‐1 have been linked to a disorder called Huppke‐Bren...

Administration of cytotoxic agents like doxorubicin (DOX) is restrained by the effects on different non-targeted/non-cancerous tissues, which instigates the development of nano-enabled drug delivery systems, among others. In this study, imaging mass spectrometry (IMS) was selected to examine the effects of DOX nanoformulations on non-targeted tissu...

With its endocrine and metabolic activity, visceral adipose tissue (VAT) is more than a storage organ. Research shows that VAT has a role in the development of cardiovascular disorders. The influence of epicardial adipose tissue (EAT, a subset of VAT) morphology on cardiovascular function and health is still limited (1). Furthermore, the data on th...

Lipid rafts, membrane microdomains enriched with (glyco)sphingolipids, cholesterol, and select proteins, act as cellular signalosomes. Various methods have been used to separate lipid rafts from bulk (non‐raft) membranes, but most often, non‐ionic detergent Triton X‐100 has been used in their isolation. However, Triton X‐100 is a reported disruptor...

Silver nanoparticles (AgNPs) are among the most commercialized nanomaterials in biomedicine due to their antimicrobial and anti-inflammatory properties. Nevertheless, possible health hazards of exposure to AgNPs are yet to be understood and therefore raise public concern in regards of their safety. In this study, sex-related differences, role of st...

This study aimed to test the effect of a 7-day high-salt (HS) diet on autonomic nervous system (ANS) activity in young healthy individuals and modulation of ANS on microvascular endothelial function impairment. 47 young healthy individuals took 7-day low-salt (LS) diet (3.5 g salt/day) followed by 7-day high-salt (HS) diet (~14.7 g salt/day). ANS a...

Background: Most studies examining tramadol metabolism have been carried out in non-surgical patients and with oral tramadol. The aim of this study was 1) to measure concentrations of tramadol, O-demethyltramadol (ODT), and N-demethyltramadol (NDT) in the surgical patients admitted to the intensive care unit (ICU) within the first 24 postoperative...

Aim: The aim of research was to evaluate the maternal serum concentration of selected endogenous steroid hormones during spontaneous parturition at term and to determinate their association with the need for oxytocin augmentation. Methods: Blood of 108 healthy pregnant women whose parturition started with the regular spontaneous uterine contract...

The aim of this study was to develop and evaluate matrix assisted LASER desorption ionization (MALDI) time-of-flight (TOF) mass spectrometry imaging (MSI) of blood smear. Integrated light microscope and MALDI IT-TOF mass spectrometer, together with a matrix sublimation device, were used for analysis of blood smears coming from healthy male donors....

Metallic nanoparticles are an important and widely used materials in development of nano-enabled medicine. For that reason, their interaction with biological molecules has to be systematically examined, as use of nanoparticles can lead to altered biological functions. In this study, we evaluated the interaction between silver nanoparticles (AgNPs)...

Introduction: There is a growing amount of evidence showing the significant analytical bias of steroid hormone immunoassays, but large number of available immunoassays makes conduction of a single comprehensive study of this issue hardly feasible. Aim of this study was to assess the analytical bias of six heterogeneous immunoassays for serum aldos...

Coronavirus disease (CoVID-19), caused by recently identified severe acute respiratory distress syndrome coronavirus 2 (SARS-CoV-2), is characterized by inconsistent clinical presentations. While many infected individuals remain asymptomatic or show mild respiratory symptoms, others develop severe pneumonia or even respiratory distress syndrome. SA...

Background: Lung cancer is the leading cause of cancer-related death worldwide, with 5-year overall survival less than 15%. Therefore, it is essential to find biomarkers for early detection and prognosis. Aberrant DNA methylation is a common feature of human cancers and its utility is already recognized in cancer management. The aim of this study...

Flavonoids are natural compounds that have been extensively studied due to their positive effects on human health. There are over 4000 flavonoids found in higher plants and their beneficial effects have been shown in vitro as well as in vivo. However, data on their pharmacokinetics and influence on metabolic enzymes is scarce. The aim of this study...

Background: Propolis is a well-known bee product containing more than 2000 identified compounds. It has many beneficial effects on human health that include antibacterial, antiviral, anticancer and hepatoprotective justifying its use as a dietary supplement. Platelet aggregation plays crucial role in thrombus formation that can cause stroke or hea...

Background Carbohydrate sulfotransferases (CHST) were shown to be involved in carcinogenesis. The aim of the study was to assess the diagnostic value of serum CHST7 concentration in differentiation between lung cancer and non-malignant pulmonary inflammations. Methods Clinical case-control study involving 125 participants was conducted: the contro...

Heparin induced thrombocytopenia (HIT) is a life-threatening disorder which diagnosis depends on laboratory evaluation. The objective of this report is to present the impact of different laboratory methods for HIT detection on the diagnostic evaluation process. In this case, a 78-year old female patient previously diagnosed with monoclonal gammopat...

Human serum albumin (HSA) binds a variety of xenobiotics, including flavonoids and warfarin. The binding of another ligand to the IIA binding site on HSA can cause warfarin displacement and potentially the elevation of its free concentration in blood. Studies dealing with flavonoid-induced warfarin displacement from HSA provided controversial resul...

Background: Human serum albumin (HSA) is the most abundant protein in human serum. It has numerous functions, one of which is transport of small hydrophobic molecules, including drugs, toxins, nutrients, hormones and metabolites. HSA has the ability to interact with a wide variety of structurally different compounds. This promiscuous, nonspecific...

Flavonoids are ubiquitous plant metabolites that interfere with different biological processes in the human organism. After absorption they bind to human serum albumin (HSA), the most abundant carrier protein in the blood which also binds various hormones and drugs. Binding of flavonoids to HSA may impact their distribution, influencing the active...

In this study we present a case of falsely elevated oestradiol (E2) concentration, determined by two immunoassays, in a breast cancer patient receiving exemestane therapy. The positive bias of immunochemical measurements was revealed using liquid chromatography tandem mass spectrometry (LC-MS/MS) which showed undetectable E2 concentration. The disc...

Flavonoids are ubiquitous plant metabolites that interfere with different biological processes in the human organism. After absorption they bind to human serum albumin (HSA), the most abundant carrier protein in the blood which also binds various hormones and drugs. Binding of flavonoids to HSA may impact their distribution, influencing the active...

Acute pyelonephritis is a severe disease which is sometimes difficult to recognize based on clinical symptoms and routinely available diagnostic tests, especially in young children. The aim of this study was to assess the diagnostic value of urinary neutrophil gelatinase-associated lipocalin (uNGAL) as a biomarker of acute pyelonephritis. In this c...

Interleukin 10 (IL-10) is important pleiotropic immunoregulatory cytokine which gene is located on chromosome 1 at 1q31-32. There are many genetic variants of IL-10 gene. However, the most studied are two dinucleotide repeats (microsatellites), IL10.G and IL10.R, located 1.2 kb and 4 kb upstream of the transcription start site and three single nucl...

Introduction of mycophenolate mofetil (MMF) in the prevention and treatment of acute kidney rejection resulted in significant improvement of graft survival as well as in improvement of patients' life span. MMF is a prodrug that undergoes pre-systemic metabolism to its active drug form, mycophenolic acid (MPA). It is commonly prescribed in a fixed d...

Current methods for determination of impurities with different charge-to-volume ratio are limited especially in terms of sensitivity and precision. The main goal of this research was to establish a quantitative method for determination of impurities with charges differing from that of recombinant human granulocyte colony-stimulating factor (rhG-CSF...

Micellar electrokinetic chromatography (MEKC) was used for the separation and determination of two iridoid glycosides, aucubin and catalpol, in several Plantago species growing in Croatia: P. altissima L., P. argentea Chaix, P. coronopus L., P. holosteum Scop. (subsp. depauperata, subsp. holosteum and subsp. scopulorum), P. lagopus L., P. lanceolat...

Heparin induced thrombocytopenia (HIT) is a serious complication of heparin administration. In the last decade, this clinical syndrome has come into the focus of interest, primarily because of the severe thromboembolic complications that may lead to lethal outcome. In addition, great improvements have been made in the treatment with direct thrombin...

Diagnostic value of available tumor markers, such as cancer antigen CA 15-3 and carcinoembryonic antigen (CEA) in breast cancer is limited. There is an ongoing search for additional, potentially better diagnostic blood markers with improved clinical utility. The aim of this study is to evaluate performance of the approach based on routine blood tes...

Flavonoids are widely distributed across the plant kingdom and are therefore common ingredients in an everyday diet. Some flavonoids have a potential to affect platelet aggregation; most often antiaggregatory effects of flavonoids are observed. The objective of this research was to evaluate the in vitro effect of a selected set of flavonoids on pla...

Among natural compounds, present in every day diet, flavonoids have shown beneficial effect in prevention of cardiovascular diseases that can be attributed, at least partially to the described antiaggregatory activity i.e. antiplatelet effects of flavonoids. Due to the ever increasing pharmacological interest in antiplatelet agents a systematic exp...

Propolis is a resinous hive product collected by honeybees from various plant sources. It is widely used in traditional medicine and is reported to have a broad spectrum of pharmacological effects (antibacterial, antihepatoxic, antioxidative, anti-inflammatory, etc.). Thus the aim of this study was to assess cytotoxic effect of various ethanol prop...

Background. The only promptly avaible testfor early diagnosis of acute kidney failure, so far, is fraction excretion of sodium (FENa). Racent studies indetified neutrophil gelatinase-associated lipocalin (NGAL) as a promising biomarker for such state. The aim of our study was to compare diagnostic usefulness of those analytes in acute tubular impai...

During the last few decades the number of available molecular descriptors has grown exponentially. A reduced set of descriptors, containing only relevant descriptors, enables better understanding of the interaction between the molecule and some biological entity and in turn, it enables more reliable molecular modeling and chemical database mining....

Background: Despite the fact that sperm function is dependent on ionic environment, its relation to male infertility is yet not clear. However, there is evidence that altered ion levels in seminal plasma correlates with decreased fertility potential. Aim: Objective of this study was to investigate association between concentration of calcium, magne...

Background: Some recent study supports the role of cobalamin in spermatogenesis and correlation with several sperm parameters. Cobalamin (vitamin B12) is bound to two proteins, transcobalamin and haptocorrin. Holotranscobalamin (also known as active B12 or holo-TC) is a metabolically active form of cobalamin, and this parameter showed promising res...

Background: Diagnostic approach to the simultaneous inheritance of betathalassemia and hereditary hemochromatosis might be quite complex due to the fact that severe beta-thalassemia itself may lead to hemochromatosis. On the other hand, beta-thalassemia minor accompanied by some heterozygous form of H FE polymorphism may also lead to the disease ma...

Background: Diagnostic approach to the simultaneous inheritance of beta-thalassemia and hereditary hemochromatosis might be quite complex due to the fact that severe beta-thalassemia itself may lead to hemochromatosis. On the other hand, beta-thalassemia minor accompanied by some heterozygous form of HFE polymorphism may also lead to the disease ma...

A new class of antimicrobial agents, 3-nitrocoumarins and related compounds, has been chosen as a subject of the present study. In order to explore their activity and molecular properties that determine their antimicrobial effects, QSAR models have been proposed. Most of the 64 descriptors used for the development were extracted from semiempirical...

In vivo study has been conducted on 47 healthy women and men in order to investigate whether daily intake of powdered propolis extract during 30 days has any influence on the following blood parameters: activity of superoxide dismutase, glutathione peroxidase and catalase, concentration of plasma malondialdehyde, total cholesterol, low- and high-de...

Capability of evolutionary neural network (ENN) based QSAR approach to direct the descriptor selection process towards stable descriptor subset (DS) composition characterized by acceptable generalization, as well as the influence of description stability on QSAR model interpretation have been examined. In order to analyze the DS stability and QSAR...

Introduction: Although recognized as a valuable tool by scientific community, microarray based gene expression profiling has not accessed routine diagnostic application during the last decade. Since this approach is expensive and prone to substantial experimental variation, it is not suited for routine clinical diagnostic purposes at the current st...

ntroduction: Although recognized as a valuable tool by scientific community, microarray based gene expression profiling has not accessed routine diagnostic application during the last decade. Since this approach is expensive and prone to substantial experimental variation, it is not suited for routine clinical diagnostic purposes at the current sta...

The gas chromatography (GC) method for enantioseparation of well-known non-steroidal anti-inflammatory drugs ibuprofen, fenoprofen and ketoprofen methyl esters mixture was developed. Best enantioseparation was performed on capillary column with heptakis-(2,3-di-O-methyl-6-O-t-butyldimethyl-silyl)-beta-cyclodextrin stationary phase and hydrogen used...

The aim of this work is comparison of the prediction power of multiple linear regression and artificial neural networks retention models for inorganic anions (fluoride, chloride, nitrite, sulfate, bromide, nitrate, and phosphate) in suppressed ion chromatography with isocratic elution. Relations between ion chromatographic parameters (eluent flow r...

The set of gene micro-arrays, which consists of two leukemia types, was used as a target to evaluate the efficiency of novel integrated data mining classification process. Discovering the most relevant subset of genes among few thousands of analyzed genes is necessary to get accurate disease classification. Dimensional complexity of the classificat...

Instead of usual rationale for chromatographic fingerprint based sample identification which relies upon visual inspection or principal component analysis of raw or aligned chromatograms novel nonparametric statistical measure of fingerprint set homogeneity is proposed. Randomization test is applied for significance analysis of fingerprint set homo...

The aim of this work is to develop an ion chromatographic method for monitoring of fluoride, chloride, nitrite, sulfate, nitrate, and phosphate in fertilizer industry wastewater. A developed method was optimized and better separation within a reasonable analysis time was obtained. Optimization was performed by using retention models obtained with a...

This article introduces a novel method for reducing dimensional complexity of classification problems which are frequently present in gene microarray analysis. Revealing the most relevant subset of genes among few thousands of analyzed genes is necessary to get accurate disease classification. Attribute (gene) filter was developed for such a purpos...

The aim of this work is the development of an artificial neural network model, which can be generalized and used in a variety of applications for retention modelling in ion chromatography. Influences of eluent flow-rate and concentration of eluent anion (OH-) on separation of seven inorganic anions (fluoride, chloride, nitrite, sulfate, bromide, ni...

The aim of this work was to develop an empirical model for retention of inorganic anions (fluoride, chloride, nitrite, sulphate, bromide, nitrate, and phosphate) in suppressed ion chromatography with hydroxide selective stationary phases using artificial neural networks. Three-layer feed-forward neural network trained with a Levenberg-Marquardt bat...

The applicability of self-organizing maps (SOM) for the classification of chromatographic systems or components of chromatographic systems based on data taken from literature is shown. The SOM approach is compared to dendrogram and principal components analysis (PCA) approaches. It has been shown that the distance between classified objects could r...

A rational selection of a restricted set from fifteen available chromatographic systems for the separation of flavonoids and phenolic acids identified in the methanolic extract of Rhamni cathartici fructus is discussed. Series of mathematical techniques for the evaluation of solvents and solvent combinations in thin-layer chromatography of flavonoi...

Lipophilicity is a property of molecular structure which is essential in predicting the transport and activity of drugs, pesticides and various xenobiotics. The most important parameter which describes lipophilicity in a numerical way is partition in coefficient P. It describes the manner in which a bioactive solute partitions between polar and non...

Lipophilicity is a prime physicochemical descriptor of xenobiotics with relevance to their biological properties. The hydrophobic interaction of drugs with a receptor and the toxicological properties are examples of a steadily increasing number of topics in which lipophilicity plays an important role. A number of empirical and theoretical approach...