Publications by authors named "Matjaz Novak"

Cannabidiol (CBD), a naturally occurring cyclic terpenoid found in Cannabis sativa L., is renowned for its diverse pharmacological benefits. Marketed as a remedy for various health issues, CBD products are utilized by patients as a supplementary therapy or post-treatment failure, as well as by healthy individuals seeking promised advantages.

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Fungi of the genus Alternaria are ubiquitous plant pathogens and saprophytes which are able to grow under varying temperature and moisture conditions as well as on a large range of substrates. A spectrum of structurally diverse secondary metabolites with toxic potential has been identified, but occurrence and relative proportion of the different metabolites in complex mixtures depend on strain, substrate, and growth conditions. This review compiles the available knowledge on hazard identification and characterization of Alternaria toxins.

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Over the past 20 years, numerous tyrosine kinase inhibitors (TKIs) have been introduced for targeted therapy of various types of malignancies. Due to frequent and increasing use, leading to eventual excretion with body fluids, their residues have been found in hospital and household wastewaters as well as surface water. However, the effects of TKI residues in the environment on aquatic organisms are poorly described.

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Article Synopsis
  • - The comet assay is a flexible method used to identify DNA damage in individual eukaryotic cells, applicable to various species from yeast to humans, detecting issues like DNA strand breaks and other forms of damage.
  • - Modifications to the protocol are necessary based on the specimen to minimize additional DNA damage during sample processing and to enhance the detection of damage differences.
  • - The method has been validated for various applications in research and has gained recognition as an in vivo genotoxicity test by the OECD, with guidelines provided for its use across different cell types and DNA damage assessments.
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Diatoms of the genus Pseudo-nitzschia are cosmopolitans spread in seas and oceans worldwide, with more than 50 described species, dozens of which have been confirmed to produce domoic acid (DA). Here, we characterized and investigated the toxicological activity of secondary metabolites excreted into the growth media of different Pseudo-nitzschia species sampled at various locations in the northern Adriatic Sea (Croatia) using human blood cells under in vitro conditions. The results revealed that three investigated species of the genus Pseudo-nitzschia were capable of producing DA indicating their toxic potential.

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Tyrosine kinase inhibitors (TKIs) are designed for targeted cancer therapy. The consumption of these drugs during the last 20 years has been constantly rising. In the zebrafish () embryo toxicity test, we assessed the toxicity of six TKIs: imatinib mesylate, erlotinib, nilotinib, dasatinib, sorafenib and regorafenib.

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Protection of patients against hospital-acquired infections is of major importance. Disinfection of magnetic resonance imaging suites is, due to their unique properties and environment particularly, difficult to implement. We developed an OPTI-JET CS MD 2ZE aerosolizator for disinfection of a magnetic resonance imaging suite using the electrolyzed oxidizing water biocide SteriplantN.

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The present study addresses the chemoprotective effects of xanthohumol (XN), a prenylated flavonoid found in the female inflorescences (hops) of the plant L., against the carcinogenic food contaminant aflatoxin B1 (AFB1). The chemical reactions of XN and its derivatives (isoxanthohumol (IXN), 8-prenylnaringenin (8-PN), and 6-prenylnaringenin (6-PN)) with the AFB1 metabolite, aflatoxin B1 exo-8,9-epoxide (AFBO), were investigated , by calculating activation free energies (ΔG) at the Hartree-Fock level of theory in combination with the 6-311++G(d,p) basis set and two implicit solvation models.

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(1) Background: The voltage-gated potassium channel K10.1 (Eag1) is considered a near- universal tumour marker and represents a promising new target for the discovery of novel anticancer drugs. (2) Methods: We utilized the ligand-based drug discovery methodology using 3D pharmacophore modelling and medicinal chemistry approaches to prepare a novel structural class of K10.

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Imatinib mesylate (IM) is an anticancer drug that belongs to tyrosine kinase inhibitors. We report the results of the first investigation of the chronic exposure of zebrafish (Danio rerio) to IM. The exposure to IM (0.

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The comet assay is a widely used test for the detection of DNA damage and repair activity. However, there are interlaboratory differences in reported levels of baseline and induced damage in the same experimental systems. These differences may be attributed to protocol differences, although it is difficult to identify the relevant conditions because detailed comet assay procedures are not always published.

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The comet assay has become one of the methods of choice for the evaluation and measurement of DNA damage. It is sensitive, quick to perform and relatively affordable for the evaluation of DNA damage and repair at the level of individual cells. The comet assay can be applied to virtually any cell type derived from different organs and tissues.

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The comet assay, also called single cell gel electrophoresis, is a sensitive, rapid and low-cost technique for quantifying and analysing DNA damage and repair at the level of individual cells. The assay itself can be applied on virtually any cell type derived from different organs and tissues of eukaryotic organisms. Although it is mainly used on human cells, the assay has applications also in the evaluation of DNA damage in yeast, plant and animal cells.

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Human papillomavirus (HPV) is an important etiological factor in oropharyngeal squamous cell carcinoma (SCC). Compared to HPV-negative tumors, HPV-positive oropharyngeal SCC has shown a better response to nonsurgical treatments. In this study, we determined the dose-modifying factors for HPV-positive tumors with single-dose irradiation, with or without low radiosensitizing doses of cisplatin.

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Anticancer drugs enter aquatic environment predominantly via hospital and municipal wastewater effluents where they may, due to their genotoxic potential, cause adverse environmental effects even at very low doses. In this study we evaluated cytotoxic and genotoxic potential of two widely used anticancer drugs, cyclophosphamide (CP) and ifosfamide (IF) as individual compounds and in a complex mixture together with 5-fluorouracil (5-FU) and cisplatin (CDDP) because these four drugs have been frequently detected in an oncological ward effluents. As an experimental model we used zebrafish liver cell (ZFL) line.

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The selective tyrosine kinase inhibitor imatinib mesylate (IM) is a widely used anticancer drug. Recent studies showing that IM can induce DNA and chromosomal damage in crustaceans and higher plants prompted us to re-examine its potential genotoxicity. IM was not mutagenic in the Ames assay (Salmonella typhimurium).

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Anticancer drugs are continuously released into hospital and urban wastewaters, where they, most commonly, undergo conventional treatment in wastewater treatment plants (WWTPs). Wastewaters contain complex mixtures of substances including parent compounds, their metabolites and transformation products (TPs). In this study, samples of hospital effluents and WWTP influents and effluents from Slovenia and Spain were analyzed for twenty-two selected anticancer drugs, their metabolites and transformation products.

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A neurotoxin β-N-methylamino-L-alanine (L-BMAA) is a non-protein amino acid produced by most cyanobacteria ubiquitously present in aquatic and terrestrial environments. Due to its global presence in surface waters, a widespread human exposure is possible and therefore this toxin represents a health risk for humans and animals. L-BMAA has been linked to the development of a variety of neurodegenerative diseases.

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Cyclophosphamide (CP) and ifosfamide (IF) are commonly used cytostatic drugs that repress cell division by interaction with DNA. The present study investigates the ecotoxicity and genotoxicity of CP, IF, their human metabolites/transformation products (TPs) carboxy-cyclophosphamide (CPCOOH), keto-cyclophosphamide (ketoCP) and N-dechloroethyl-cyclophosphamide (NdCP) as individual compounds and as mixture. The two parent compounds (CP and IF), at concentrations up to 320 mg L(-1), were non-toxic towards the alga Pseudokirchneriella subcapitata and cyanobacterium Synecococcus leopoliensis.

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In chemotherapy, various anti-cancer drugs with different mechanisms of action are used and may represent different risk of undesirable delayed side effects in treated patients as well as in occupationally exposed populations. The aim of the present study was to evaluate genotoxic potential of four widely used anti-cancer drugs with different mechanisms of action: 5-fluorouracil (5-FU), cisplatin (CDDP) and etoposide (ET) that cause cell death by targeting DNA function and imatinib mesylate (IM) that inhibits targeted protein kinases in cancer cells in an experimental model with human hepatoma HepG2 cells. After 24 h of exposure all four anti-cancer drugs at non-cytotoxic concentrations induced significant increase in formation of DNA double strand breaks (DSBs), with IM being the least effective.

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Due to their increasing use, the residues of anti-neoplastic drugs have become emerging pollutants in aquatic environments. Most of them directly or indirectly interfere with the cell's genome, which classifies them into a group of particularly dangerous compounds. The aim of the present study was to conduct a comparative in vitro toxicological characterisation of three commonly used cytostatics with different mechanisms of action (5-fluorouracil [5-FU], cisplatin [CDDP] and etoposide [ET]) towards zebrafish liver (ZFL) cell line, human hepatoma (HepG2) cells and human peripheral blood lymphocytes (HPBLs).

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Residues of anti-neoplastic drugs represent new and emerging pollutants in aquatic environments. Many of these drugs are genotoxic, and it has been postulated that they can cause adverse effects in aquatic ecosystems. 5-Fluorouracil (5-FU) is one of the most extensively used anti-neoplastic drugs in cancer therapy, and this article describes the results of the first investigation using a two-generation toxicity study design with zebrafish (Danio rerio).

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The newly emerging cyanobacterial cytotoxin cylindrospermopsin (CYN) is increasingly found in surface freshwaters, worldwide. It poses a potential threat to humans after chronic exposure as it was shown to be genotoxic in a range of test systems and is potentially carcinogenic. However, the mechanisms of CYN toxicity and genotoxicity are not well understood.

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Previous studies showed that xanthohumol (XN), a hop derived prenylflavonoid, very efficiently protects against genotoxicity and potential carcinogenicity of the food borne carcinogenic heterocyclic aromatic amine (HAA) 2-amino-3-methylimidazo[4,5-f]quinoline (IQ). In this study, we showed that XN was not mutagenic in Salmonella typhimurium TA98 and did not induce genomic instability in human hepatoma HepG2 cells. In the bacteria XN suppressed the formation of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 2-amino-3,8 dimethylimidazo[4,5-f]quinoxaline (MeIQx) induced mutations in a dose dependent manner and in HepG2 cells it completely prevented PhIP and MeIQx induced DNA strand breaks at nanomolar concentrations.

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