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Tomasz Kostrzewa,1 Izabela Nowak,2 Agnieszka Feliczak-Guzik,2 Joanna Drzeżdżon,3 Dagmara Jacewicz,3 Magdalena Górska-Ponikowska,1,4,5 Alicja Kuban-Jankowska1 1Department of Medical Chemistry, Faculty of Medicine, Medical University of Gdansk, Gdansk, 80-211, Poland; 2Department of Applied Chemistry, Faculty of Chemistry, Adam Mickiewicz University, Poznań, 61-614, Poland; 3Department of Environmental Technology, Faculty of Chemistry, University of Gdansk, Gdansk, 80-308, Poland; 4IEMEST Istituto Euro-Mediterraneo di Scienza e Tecnologia, Palermo, 90127, Italy; 5Department of Biophysics, Institute of Biomaterials and Biomolecular Systems, University of Stuttgart, Stuttgart, 70174, GermanyCorrespondence: Tomasz Kostrzewa; Alicja Kuban-Jankowska, Department of Medical Chemistry, Faculty of Medicine, Medical University of Gdansk, Gdansk, 80-211, Poland, Tel +48 58 349 14 50, Fax +48 58 349 14 56, Email tomasz.kostrzewa@gumed.edu.pl; alicja.kuban-jankowska@gumed.edu.plIntroduction: Solid lipid nanoparticles (SLN) have been considered lately as promising drug delivery system in treatment of many human diseases including cancers. We previously studied potential drug compounds that were effective inhibitors of PTP1B phosphatase – possible target for breast cancer treatment. Based on our studies, two complexes were selected for encapsulation into the SLNs, the compound 1 ([VO(dipic)(dmbipy)] · 2 H2O) and compound 2 ([VOO(dipic)](2-phepyH) · H2O). Here, we investigate the effect of encapsulation of those compounds on cell cytotoxicity against MDA-MB-231 breast cancer cell line. The study also included the stability evaluation of the obtained nanocarriers with incorporated active substances and characterization of their lipid matrix. Moreover, the cell cytotoxicity studies against the MDA-MB-231 breast cancer cell line in comparison and in combination with vincristine have been performed. Wound healing assay was carried out to observe cell migration rate.Methods: The properties of the SLNs such as particle size, zeta potential (ZP), and polydispersity index (PDI) were investigated. The morphology of SLNs was observed by scanning electron microscopy (SEM), while the crystallinity of the lipid particles was analyzed by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The cell cytotoxicity of complexes and their encapsulated forms was carried out against MDA-MB-231 breast cancer cell line using standard MTT protocols. The wound healing assay was performed using live imaging microscopy.Results: SLNs with a mean size of 160 ± 25 nm, a ZP of − 34.00 ± 0.5, and a polydispersity index of 30 ± 5% were obtained. Encapsulated forms of compounds showed significantly higher cytotoxicity also in co-incubation with vincristine. Moreover, our research shows that the best compound was complex 2 encapsulated into lipid nanoparticles.Conclusion: We observed that encapsulation of studied complexes into SLNs increases their cell cytotoxicity against MDA-MB-231 cell line and enhanced the effect of vincristine.Keywords: solid lipid nanoparticles, stability of nanoparticles, oxovanadium(IV) and dioxovanadium(V) complexes, triple-negative MDA-MB-231 breast cancer cell line, live imaging microscopy

Isocyanides and isocyanates are some of the most reactive compounds in organic chemistry, making them perceived as compounds with high potential for use in both the laboratory and industry. With their high reactivity also comes several disadvantages, most notably their potentially high toxicity. The following article is a collection of information on the toxic effects of the isocyanide group on the human body and the environment. Information on the mechanism of how these harmful substances affect living tissues and the environment, worldwide information on how to protect against these chemicals, current regulations, and exposure limits for specific countries is compiled. The latest research on the application uses of isocyanates and isocyanides is also outlined, as well as the latest safer and greener methods and techniques to work with these compounds. Additionally, the presented article can serve as a brief guide to the organic toxicity of a group of isocyanates and isocyanates., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Large-scale cement production generates significant amounts of carbon dioxide from the breakdown of limestone, contributing to environmental pollution. Clean production of eco-friendly three-dimensional geopolymers can be used as environmentally friendly building materials. Replacing Portland cement with eco-friendly materials correlates with reduced energy consumption, costs, and negative environmental impact. In addition, geopolymer cement has above-average physical and chemical properties, which in many cases exceed conventional Portland cement. The literature review summarizes the latest research in the production of geopolymers following the principles of green chemistry and sustainable development goals. Examples of upcycling of construction waste, industrial waste (fly ash, silica fume, slag, tailing), demolition waste, agriculture solid waste (rice husk, palm oil), and mining waste into functional geopolymer materials will be discussed. Additionally, the review focused on innovative applications and physicochemical properties of functional geopolymer materials., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

There are few literature reports on using precatalysts based on ruthenium(II/III) ions in the polymerization of olefins. Therefore, a new coordination compound was designed based on ruthenium(III) ion and 2-phenylpyridine. The resulting monocrystal was characterized by X-ray diffraction (XRD), solid-state (photo)IR spectroscopy, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The new ruthenium(III) complex compound was used as a precatalyst in the oligomerization reactions of ethylene, 2-propen-1-ol, 2-chloro-2-propen-1-ol, 3-butene-2-ol and 2,3-dibromo-2-propen-1-ol with methylaluminoxane and ethylaluminium dichloride as activators. The catalytic activity of the newly discovered ruthenium(III) complex compound ranges from 159.5 (for 2-chloro-2-propen-1-ol) to 755.6 (for ethylene) g mmol -1 h -1 bar -1 , indicating that it is a chemical compound with high catalytic activity. In addition, the oligomerization reaction products were subjected to physicochemical characterization, using BET (Brunauer-Emmett-Teller isotherm), mass spectrometry (MALDI-TOF-MS), Fourier transform infrared (FT-IR) spectroscopy, NMR, TGA, differential scanning calorimetry (DSC), and the morphology of the porous polymeric materials was investigated by SEM. The distinguishing feature of the obtained precatalyst is its high catalytic activity under mild reaction conditions, a rare phenomenon. Compared with other precatalysts, it is the most active ruthenium(II/III) ion-based catalytic material used in oligo- and polymerization reactions of ethylene.

Estrogens function in numerous physiological processes including controlling brain cell growth and differentiation. 2-Methoxestradiol (2-ME2), a 17β-estradiol (E2) metabolite, is known for its anticancer effects as observed both in vivo and in vitro. 2-ME2 affects all actively dividing cells, including neurons. The study aimed to determine whether 2-ME2 is a potentially cancer-protective or rather neurodegenerative agent in a specific tissue culture model as well as a clinical setup. In this study, 2-ME2 activity was determined in a Parkinson's disease (PD) in vitro model based on the neuroblastoma SH-SY5Y cell line. The obtained results suggest that 2-ME2 generates nitro-oxidative stress and controls heat shock proteins (HSP), resulting in DNA strand breakage and apoptosis. On the one hand, it may affect intensely dividing cells preventing cancer development; however, on the other hand, this kind of activity within the central nervous system may promote neurodegenerative diseases like PD. Thus, the translational value of 2-ME2's neurotoxic activity in a PD in vitro model was also investigated. LC-MS/MS technique was used to evaluate estrogens and their derivatives, namely, hydroxy and methoxyestrogens, in PD patients' blood, whereas the stopped-flow method was used to assess hydrogen peroxide (H 2 O 2 ) levels. Methoxyestrogens and H 2 O 2 levels were increased in patients' blood as compared to control subjects, but hydoxyestrogens were simultaneously decreased. From the above, we suggest that the determination of plasma levels of methoxyestrogens and H 2 O 2 may be a novel PD biomarker. The presented research is the subject of the pending patent application "The use of hydrogen peroxide and 17β-estradiol and its metabolites as biomarkers in the diagnosis of neurodegenerative diseases," no. P.441360., (© 2023. The Author(s).)

In this paper, a synthesis of two innovative coordination compounds, based on chromium(III) and cobalt(II) ions with N,O-donor ligands (nitrilotriacetate, dipicolinate) and 4-acetylpyridine, is reported. The obtained metal-organic compounds were structurally characterized using the single-crystal X-ray diffraction (XRD) method. The well-defined chromium(III) and cobalt(II) complexes were used as precatalysts in the oligomerization reaction of 2-chloro-2-propen-1-ol and 2-propen-1-ol with methylaluminoxane (MMAO) as an activator. The products of the oligomerization reaction were subjected to full physicochemical characteristics, i.e., time-of-flight mass spectrometry (MALDI-TOF-MS), TGA, and differential scanning calorimetry (DSC) methods. The catalytic activity of the precatalysts in both reactions was calculated and compared with other catalysts known in the literature.

Designing catalyst systems based on transition metal ions and activators using the principles of green chemistry is a fundamental research goal of scientists due to the reduction of poisonous solvents, metal salts and organic ligands released into the environment. Urgent measures to reduce climate change are in line with the goals of sustainable development and the new restrictive laws ordained by the European Union. In this report, we attempted to use known oxovanadium(IV) green complex compounds with O, N and S donor ligands, i.e., [VO(TDA)phen] • 1.5 H 2 O (TDA = thiodiacetate), (phen = 1,10-phenanthroline), oxovanadium(IV) microclusters with 2-phenylpyridine (oxovanadium(IV) cage), [VOO(dipic)(2-phepyH)] • H 2 O (dipic = pyridine-2,6-dicarboxylate anion), (2-phepyH = 2-phenylpyridine), [VO(dipic)(dmbipy)] • 2H 2 O (dmbipy = 4,4'-dimethoxy-2,2'-dipyridyl) and [VO(ODA)(bipy)] • 2 H 2 O (ODA = oxydiacetate), (bipy = 2,2'-bipyridine), as precatalysts in oligomerization reactions of 3-buten-2-ol, 2-propen-1-ol, 2-chloro-2-propen-1-ol and 2,3-dibromo-2-propen-1-ol. The precatalysts, in most cases, turned out to be highly active because the catalytic activity exceeded 1000 g mmol -1 ·h -1 . In addition, the oligomers were characterized by Fourier-transform infrared spectroscopy (FTIR), matrix-assisted laser desorption/ionization (MALDI-TOF-MS), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques.

One of the main goals of recent bioinorganic chemistry studies has been to design and synthesize novel substances to treat human diseases. The promising compounds are metal-based and metal ion binding components such as vanadium-based compounds. The potential anticancer action of vanadium-based compounds is one of area of investigation in this field. In this study, we present five oxovanadium(IV) and dioxovanadium(V) complexes as potential PTP1B inhibitors with anticancer activity against the MCF-7 breast cancer cell line, the triple negative MDA-MB-231 breast cancer cell line, and the human keratinocyte HaCaT cell line. We observed that all tested compounds were effective inhibitors of PTP1B, which correlates with anticancer activity. [VO(dipic)(dmbipy)]·2 H 2 O (Compound 4 ) and [VOO(dipic)](2-phepyH)·H 2 O (Compound 5 ) possessed the greatest inhibitory effect, with IC 50 185.4 ± 9.8 and 167.2 ± 8.0 nM, respectively. To obtain a better understanding of the relationship between the structure of the examined compounds and their activity, we performed a computer simulation of their binding inside the active site of PTP1B. We observed a stronger binding of complexes containing dipicolinic acid with PTP1B. Based on our simulations, we suggested that the studied complexes exert their activity by stabilizing the WPD-loop in an open position and limiting access to the P-loop.

Polyolefins are used in everyday life, including in the production of many types of plastic. In addition, polyolefins account for over 50% of the polymers produced in the world. After conducting the oligomerization reactions of 2-propen-1-ol, 2-chloro-2-propen-1-ol, and norborene, polyolefins are obtained. In this report, two complexes of oxovanadium(IV) and dioxovanadium(V) with dipicolinate, 2-phenylyridine, and 4,4'-dimethoxy-2,2'-bipyridyl as precatalysts for 2-propen-1-ol, 2-chloro-2-propen-1-ol, and norborene oligomerizations are prepared. We present for the first time the new dipicolinate complex compound of oxovanadium(IV) with 4,4'-dimetoxy-2,2'-bipyridyl. Both complexes were tested for catalytic activity in the oligomerization reactions of 2-propen-1-ol, 2-chloro-2-propen-1-ol, and norbornene. Both synthesized complexes showed high catalytic activity in these oligomerization reactions, except for the oligomerization of norbornene.

Nowadays, studies are carried out on the design and synthesis of new catalysts for olefin oligomerization and polymerization, which would contain non-toxic metals and at the same time show high catalytic activities. Complex compounds of transition metal ions such as Fe(II), Cr(III) and Zr(II) containing pyridine or quinoline as ligands show at least moderate catalytic activity in ethylene and propylene polymerizations. To investigate the catalytic activity of the complex containing pyridine ligands and quinoline derivatives, here we have synthesized the crystals of new bis(5-chloroquinolin-8-olato)-bis(pyridine)-cobalt(II) solvate. The synthesized cobalt(II) complex compound was tested in reactions of 2-chloro-2-propen-1-ol and norbornene oligomerizations. Our studies showed that bis(5-chloroquinolin-8-olato)-bis(pyridine)-cobalt(II) after activation by MMAO-12 catalyzes the formation of oligomers in nitrogen atmosphere, under atmospheric pressure and at room temperature. Bis(5-chloroquinolin-8-olato)-bis(pyridine)-cobalt(II) possesses moderate catalytic activity in the formation of norbornene oligomers process and low catalytic activity in 2-chloro-2-propen-1-ol oligomerization., (© 2022. The Author(s).)

Currently, new precatalysts for olefin oligomerization are being sought in the group of vanadium(IV) complexes. Thus, the aim of our research was to examine the catalytic activity of the oxovanadium(IV) dipicolinate complex [VO(dipic)(H 2 O) 2 ] 2 H 2 O (dipic = pyridine-2,6-dicarboxylate anion) in 2-propen-1-ol oligomerization as well as to characterize oligomerization products using matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF-MS), infrared spectroscopy (IR) and nuclear magnetic resonance (NMR). The oligomerization process took place at room temperature, under atmospheric pressure and under nitrogen atmosphere to prevent oxidation of the activator MMAO-12-the modified methylaluminoxane (7 wt.%) aluminum in toluene. The last point was to determine the catalytic activity of the complex in the oligomerization reaction of 2-propen-1-ol. The aspect that enriches this work is the proposed mechanism of oligomerization of allyl alcohol based on the literature.

So far, few microclusters containing vanadium have been described in the literature. In this report, the synthesis protocol for the preparation of oxovanadium (IV) microclusters with 2-phenylpyridine is shown for the first time. Moreover, the crystal structure of these microclusters is also studied through the use of X-rays. The morphology of the prepared crystals is investigated using a field-emission Scanning Electron Microscope (SEM). The new compound, after activation by modified methylaluminoxane as the catalytic system, is investigated regarding the oligomerizations of 3-buten-1-ol, 2-chloro-2-propen-1-ol, allyl alcohol, and 2,3-dibromo-2-propen-1-ol. The products of oligomerization are tested by the TG-FTIR and MALDI-TOF-MS methods. Moreover, the values of catalytic activities for the new oxovanadium(IV) microclusters with 2-phenylpyridine are determined for the 3-buten-1-ol, 2-chloro-2-propen-1-ol, allyl alcohol, and 2,3-dibromo-2-propen-1-ol oligomerizations. Oxovanadium(IV) microclusters with 2-phenylpyridine are shown to be very highly active precatalysts for the oligomerization of allyl alcohol, 2,3-dibromo-2-propen-1-ol, and 3-buten-1-ol. However, in the case of 2-chloro-2-propen-1-ol oligomerization, the new microclusters are seen as highly active precatalysts.

Breast cancer is the most common cancer of women-it affects more than 2 million women worldwide. PTP1B phosphatase can be one of the possible targets for new drugs in breast cancer therapy. In this paper, we present new curcumin derivatives featuring a 4-piperidone ring as PTP1B inhibitors and ROS inducers. We performed cytotoxicity analysis for twelve curcumin derivatives against breast cancer MCF-7 and MDA-MB-231 cell lines and the human keratinocyte HaCaT cell line. Furthermore, because curcumin is a known antioxidant, we assessed antioxidant effects in its derivatives. For the most potent cytotoxic compounds, we determined intracellular ROS and PTP1B phosphatase levels. Moreover, for curcumin and its derivatives, we performed real-time microscopy to observe the photosensitizing effect. Finally, computational analysis was performed for the curcumin derivatives with an inhibitory effect against PTP1B phosphatase to assess the potential binding mode of new inhibitors within the allosteric site of the enzyme. We observed that two tested compounds are better anticancer agents than curcumin. Moreover, we suggest that blocking the -OH group in phenolic compounds causes an increase in the cytotoxicity effect, even at a low concentration. Furthermore, due to this modification, a higher level of ROS is induced, which correlates with a lower level of PTP1B.

Oxidative stress plays an important role in the pathogenesis of many serious diseases, including cancer, atherosclerosis, coronary artery disease, Parkinson's disease, Alzheimer's disease, stroke and myocardial infarction. In the body's natural biochemical processes, harmful free radicals are formed, which can be removed with the help of appropriate enzymes, a balanced diet or the supply of synthetic antioxidant substances such as flavonoids, vitamins or anthocyanins to the body. Due to the growing demand for antioxidant substances, new complex compounds of transition metal ions with potential antioxidant activity are constantly being sought. In this study, four oxovanadium(IV) and dioxovanadium(V) dipicolinate (dipic) complexes with 1,10-phenanthroline (phen), 2,2'-bipyridyl (bipy) and the protonated form of 2-phenylpyridine (2-phephyH): (1) [VO(dipic)(H 2 O) 2 ]·2 H 2 O, (2) [VO(dipic)(phen)]·3 H 2 O, (3) [VO(dipic)(bipy)]·H 2 O and (4) [VOO(dipic)](2-phepyH)·H 2 O were synthesized including one new complex, so far unknown and not described in the literature, i.e., [VOO(dipic)](2-phepyH)·H 2 O. The oxovanadium(IV) dipicolinate complexes with 1,10-phenanthroline and 2,2'-bipyridyl have been characterized by several physicochemical methods: NMR, MALDI-TOF-MS, IR, but new complex [VOO(dipic)](2-phepyH)·H 2 O has been examined by XRD to confirm its structure. The antioxidant activities of four complexes have been examined by the nitrotetrazolium blue (NBT) method towards superoxide anion. All complexes exhibit high reactivity with superoxide anion and [VOO(dipic)](2-phepyH)·H 2 O has higher antioxidant activity than L-ascorbic acid. Our studies confirmed that high basicity of the auxiliary ligand increases the reactivity of the complex with the superoxide radical.

Photodynamic therapy (PDT) has become an alternative to standard cancer treatment methods such as surgery, chemotherapy and radiotherapy. The uniqueness of this method relies on the possibility of using various photosensitizers (PS) that absorb and convert light emission in radical oxygen-derived species (ROS). They can be present alone or in the presence of other compounds such as metal organic frameworks (MOFs), non-tubules or polymers. The interaction between DNA and metal-based complexes plays a key role in the development of new anti-cancer drugs. The use of coordination compounds in PDT has a significant impact on the amount ROS generated, quantum emission efficiency (Φem) and phototoxic index (PI). In this review, we will attempt to systematically review the recent literature and analyze the coordination complexes used as PS in PDT. Finally, we compared the anticancer activities of individual coordination complexes and discuss future perspectives. So far, only a few articles link so many transition metal ion coordination complexes of varying degrees of oxidation, which is why this review is needed by the scientific community to further expand this field worldwide. Additionally, it serves as a convenient collection of important, up-to-date information.

The contemporary search for new catalysts for olefin oligomerization and polymerization is based on the study of coordinating compounds and/or organometallic compounds as post-metallocene catalysts. However known catalysts are suffered by many flaws, among others unsatisfactory activity, requirement of high pressure or instability at high temperatures. In this paper, we present a new catalyst i.e. the crystalline complex compound possesing high catalytic activity in the oligomerization of olefins, such as 2-chloro-2-propen-1-ol and ethylene under very mild conditions (room temperature, 0.12 bar for ethylene oligomerization, atmospheric pressure for 2-chloro-2-propen-1-ol oligomerization). New material-Cat-CrNP ([nitrilotriacetato-1,10-phenanthroline]chromium(III) tetrahydrate) has been obtained as crystalline form of the nitrilotriacetate complex compound of chromium(III) with 1,10-phenanthroline and characterized in terms of its crystal structure by the XRD method and by multi-analytical investigations towards its physicochemical propeties The yield of catalytic oligomerization over Cat-CrNP reached to 213.92 g · mmol -1 · h -1 · bar -1 and 3232 g · mmol -1 · h -1 · bar -1 for the 2-chloro-2-propen-1-ol and ethylene, respectively. Furthemore, the synthesis of Cat-CrNP is cheap, easy to perform and solvents used during preparation are environmentally friendly., (© 2021. The Author(s).)

Mitochondria, as "power house of the cell", are crucial players in cell pathophysiology. Beyond adenosine triphosphate (ATP) production, they take part in a generation of reactive oxygen species (ROS), regulation of cell signaling and cell death. Dysregulation of mitochondrial dynamics may lead to cancers and neurodegeneration; however, the fusion/fission cycle allows mitochondria to adapt to metabolic needs of the cell. There are multiple data suggesting that disturbed mitochondrial homeostasis can lead to Parkinson's disease (PD) development. 2-methoxyestradiol (2-ME), metabolite of 17β-estradiol (E2) and potential anticancer agent, was demonstrated to inhibit cell growth of hippocampal HT22 cells by means of nitric oxide synthase (NOS) production and oxidative stress at both pharmacologically and also physiologically relevant concentrations. Moreover, 2-ME was suggested to inhibit mitochondrial biogenesis and to be a dynamic regulator. This review is a comprehensive discussion, from both scientific and clinical point of view, about the influence of 2-ME on mitochondria and its plausible role as a modulator of neuron survival.

The report focuses on the new precatalysts for ethylene oligomerization. The five chromium(III) complex compounds containing the following ligands: dipicolinate anion, oxalate anion, 5-aminopyridine-2-carboxylate anion, 2,2'-bipyridine and 4,4'-dimethoxy-2,2'-bipyridine have been examined towards catalytic activity for ethylene oligomerization. The chromium(III) complexes have been activated by modified methylaluminoxane. The obtained oligomers have been investigated by MALDI-TOF-MS, thermal analysis and infrared spectroscopy. The results revealed that the examined chromium(III) complexes are highly active catalysts for ethylene oligomerization. The values of catalytic activities of the examined complexes are in the range 1860 - 3798 g∙mmol -1 ∙h -1 ∙bar -1 .

This publication presents the new trends and opportunities for further development of coordination compounds used in the chemical industry. The review describes the influence of various physicochemical factors regarding the coordination relationship (for example, steric hindrance, electron density, complex geometry, ligand), which condition technological processes. Coordination compounds are catalysts in technological processes used during organic synthesis, for example: Oxidation reactions, hydroformylation process, hydrogenation reaction, hydrocyanation process. In this article, we pointed out the possibilities of using complex compounds in catalysis, and we noticed what further research should be undertaken for this purpose.

2-methoxyestradiol (2-ME) is a physiological anticancer compound, metabolite of 17β-estradiol. Previously, our group evidenced that from mechanistic point of view one of anticancer mechanisms of action of 2-ME is specific induction and nuclear hijacking of neuronal nitric oxide synthase (nNOS), resulting in local generation of nitro-oxidative stress and finally, cancer cell death. The current study aims to establish the substantial mechanism of generation of reactive nitrogen species by 2-ME. We further achieved to identify the specific reactive nitrogen species involved in DNA-damaging mechanism of 2-ME. The study was performed using metastatic osteosarcoma 143B cells. We detected the release of biologically active (free) nitric oxide ( • NO) with concurrent measurements of peroxynitrite (ONOO - ) in real time in a single cell of 143B cell line by using • NO/ONOO - sensitive microsensors after stimulation with calcium ionophore. Detection of nitrogen dioxide ( • NO 2 ) and determination of chemical rate constants were carried out by a stopped-flow technique. The affinity of reactive nitrogen species toward the guanine base of DNA was evaluated by density functional theory calculations. Expression and localization of nuclear factor NF-kB was determined using imaging cytometry, while cell viability assay was evaluated by MTT assay. Herein, we presented that 2-ME triggers pro-apoptotic signalling cascade by increasing cellular reactive nitrogen species overproduction - a result of enzymatic uncoupling of increased nNOS protein levels. In particular, we proved that ONOO - and • NO 2 directly formed from peroxynitrous acid (ONOOH) and/or by auto-oxidation of • NO, are inducers of DNA damage in anticancer mechanism of 2-ME. Specifically, the affinity of reactive nitrogen species toward the guanine base of DNA, evaluated by density functional theory calculations, decreased in the order: ONOOH > ONOO -  >  • NO 2  >  • NO. Therefore, we propose to consider the specific inducers of nNOS as an effective tool in the field of chemotherapy., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

Elevated levels of reactive nitrogen species, alteration in redox balance and deregulated redox signaling are common hallmarks of cancer progression and chemoresistance. However, depending on the cellular context, distinct reactive nitrogen species are also hypothesized to mediate cytotoxic activity and are thus used in anticancer therapies. We present here the dual face of nitric oxide and its derivatives in cancer biology. Main derivatives of nitric oxide, such as nitrogen dioxide and peroxynitrite cause cell death by inducing protein and lipid peroxidation and/or DNA damage. Moreover, they control the activity of important protein players within the pro- and anti-apoptotic signaling pathways. Thus, the control of intracellular reactive nitrogen species may become a sophisticated tool in anticancer strategies., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The impact of oxydiacetate oxidovanadium(IV) complexes on plants is currently unknown. This report demonstrates the influence of these complexes on Arabidopsis thaliana (L.) Heynh. In the presence of 10-6M vanadium(IV) complexes, plants proceeded through their entire life cycle, with the occurrence of proper morphological and cytological organisation of leaf and root tissues. The addition of 10-1M H2O2 caused root damage, leaf necrosis, and plant death at around the seventh day, due to the destruction of the root system. Pretreatment of the plants with 10-6M of vanadium(IV) compounds: VOSO4 and VO(oda), alleviated the effects of H2O2 to some extent. Plants pretreated with 10-6M vanadium(IV) complexes survived longer despite the presence of H2O2. Considering the higher rate of plant survival in the presence of VOSO4, and the relatively high photosynthetic parameters and anthocyanin contents in the cells, we conclude that this vanadium(IV) compound can have positive effects on plants that are grown under stress conditions.

Environmental contaminants, such as heavy metals, nanomaterials, and pesticides, induce the formation of reactive oxygen and nitrogen species (RONS). Plants interact closely with the atmosphere, water, and soil, and consequently RONS intensely affect their biochemistry. For the past 30 years researchers have thoroughly examined the role of RONS in plant organisms and oxidative modifications to cellular components. Hydrogen peroxide, superoxide anion, nitrogen(II) oxide, and hydroxyl radicals have been found to take part in many metabolic pathways. In this review the various aspects of the oxidative stress induced by environmental contamination are described based on an analysis of literature. The review reinforces the contention that RONS play a dual role, that is, both a deleterious and a beneficial one, in plants. Environmental contamination affects human health, also, and so we have additionally described the impact of RONS on the coupled human - environment system., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The antioxidant properties of oxydiacetate complexes of cobalt(II) and nickel(II) with 1,10-phenantroline and 2,2'-bipyridine have been investigated towards the superoxide radical using the nitro blue tetrazolium chloride (NBT) test and the cyclic voltammetry (CV). Moreover, the biological activity of the complexes under study has been investigated in the Human Dermal Fibroblasts adult (HDFa) cell line. In the first step, the cytotoxic and the antiproliferative activities of the complexes were examined. Subsequently, the cytoprotective properties of the complexes have been investigated in an oxidative stress conditions induced by H 2 O 2 .

Pancreatic ductal adenocarcinoma is one of the most aggressive human malignancies, where the 5-year survival rate is less than 4% worldwide. Successful treatment of pancreatic cancer is a challenge for today's oncology. Several studies showed that increased levels of oxidative stress may cause cancer cells damage and death. Therefore, we hypothesized that oxidative as well as nitro-oxidative stress is one of the mechanisms inducing pancreatic cancer programmed cell death. We decided to use silver nanoparticles (AgNPs) (2.6 and 18 nm) as a key factor triggering the reactive oxygen species (ROS) and reactive nitrogen species (RNS) in pancreatic ductal adenocarcinoma cells (PANC-1). Previously, we have found that AgNPs induced PANC-1 cells death. Furthermore, it is known that AgNPs may induce an accumulation of ROS and alteration of antioxidant systems in different type of tumors, and they are indicated as promising agents for cancer therapy. Then, the aim of our study was to evaluate the implication of oxidative and nitro-oxidative stress in this cytotoxic effect of AgNPs against PANC-1 cells. We determined AgNP-induced increase of ROS level in PANC-1 cells and pancreatic noncancer cell (hTERT-HPNE) for comparison purposes. We found that the increase was lower in noncancer cells. Reduction of mitochondrial membrane potential and changes in the cell cycle were also observed. Additionally, we determined the increase in RNS level: nitric oxide (NO) and nitric dioxide (NO 2 ) in PANC-1 cells, together with increase in family of nitric oxide synthases (iNOS, eNOS, and nNOS) at protein and mRNA level. Disturbance of antioxidant enzymes: superoxide dismutase (SOD1, SOD2, and SOD3), glutathione peroxidase (GPX-4) and catalase (CAT) were proved at protein and mRNA level. Moreover, we showed cells ultrastructural changes, characteristic for oxidative damage. Summarizing, oxidative and nitro-oxidative stress and mitochondrial disruption are implicated in AgNPs-mediated death in human pancreatic ductal adenocarcinoma cells.

The new 2-pyridinecarboxylate (2-pic) complex of chromium(III) has been designed and synthesized as a new highly active and selective oligomerization catalyst. The crystal structure of the new compound has been determined by X-ray diffraction. The composition and purity of [Cr(2-pic) 2 (OH 2 ) 2 ]NO 3 have been confirmed by several spectroscopic methods and the elemental analysis. Furthermore, the new complex has been investigated towards its catalytic activity for the oligomerization of 2-chloro-2-propen-1-ol under the atmospheric pressure and at room temperature. It has turned out that the novel catalyst exhibits a very high catalytic activity. Consequently, [Cr(2-pic) 2 (OH 2 ) 2 ]NO 3 belongs to a new generation of non-metallocene catalysts.

The new type of catalysts designed for the olefin derivatives polymerization has been synthetized. The novel catalysts are chromium(III) salt type complexes composed of both organic cation and anion, i.e. [Cr(dipic) 2 ][Cr(bipy)(dipic)H 2 O]∙2H 2 O and [Cr(dipic) 2 ]Hdmbipy∙2.5 H 2 O. The compositions of these complexes have been confirmed by a number of instrumental methods including NMR, IR, UV-Vis, MS and elemental analysis ones. Moreover, the crystal structures of these novel catalysts were determined and reported. Furthermore, the [Cr(dipic) 2 ][Cr(bipy)(dipic)H 2 O]∙2H 2 O and [Cr(dipic) 2 ]Hdmbipy∙2.5H 2 O complexes have been studied towards their catalytic activity, after the activation by MMAO (modified methylaluminoxane), in the case of 2-chloro-2-propen-1-ol polymerization at 21 °C and atmospheric pressure. It has been found that novel catalysts, [Cr(dipic) 2 ][Cr(bipy)(dipic)H 2 O]∙2H 2 O and [Cr(dipic) 2 ]Hdmbipy∙2.5 H 2 O, exhibit a very high catalytic activity in the process of the polymerization of the beta-olefin derivatives. The products of a such catalyzed polymerization are the poly(allyl alcohol) derivatives.

The influence of the different side chain residues on the thermodynamic and kinetic parameters for complexation reactions of the Co 2 + and Ni 2 + ions has been investigated by using the isothermal titration calorimetry (ITC) technique supported by potentiometric titration data. The study was concerned with the 2 common tripodal aminocarboxylate ligands, namely, nitrilotriacetic acid and N-(2-hydroxyethyl) iminodiacetic acid. Calorimetric measurements (ITC) were run in the 2-(N-morpholino)ethanesulfonic acid hydrate (2-(N-morpholino) ethanesulfonic acid), piperazine-N,N'-bis(2-ethanesulfonic acid), and dimethylarsenic acid buffers (0.1 mol L -1 , pH 6) at 298.15 K. The quantification of the metal-buffer interactions and their incorporation into the ITC data analysis enabled to obtain the pH-independent and buffer-independent thermodynamic parameters (K, ΔG, ΔH, and ΔS) for the reactions under study. Furthermore, the kinITC method was applied to obtain kinetic information on complexation reactions from the ITC data. Correlations, based on kinetic and thermodynamic data, between the kinetics of formation of Co 2 + and Ni 2 + complexes and their thermodynamic stabilities are discussed., (Copyright © 2016 John Wiley & Sons, Ltd.)

The use of protonated N-heterocyclic compound, i.e. 2,2'-bipyridinium cation, [bpyH + ], enabled to obtain the new nitrilotriacetate oxidovanadium(IV) salt of the stoichiometry [bpyH][VO(nta)(H 2 O)]H 2 O. The X-ray measurements have revealed that the compound comprises the discrete mononuclear [VO(nta)(H 2 O)] - coordination ion that can be rarely found among other known compounds containing nitrilotriacetate oxidovanadium(IV) moieties. The antitumor activity of [bpyH][VO(nta)(H 2 O)]H 2 O and its phenanthroline analogue, [phenH][VO(nta)(H 2 O)](H 2 O) 0.5 , towards human osteosarcoma cell lines (MG-63 and HOS) has been assessed (the LDH and BrdU tests) and referred to cis-Pt(NH 3 ) 2 Cl 2 (used as a positive control). The compounds exert a stronger cytotoxic effect on MG-63 and HOS cells than in untransformed human osteoblast cell line. Thus, the [VO(nta)(H 2 O)] - containing coordination compounds can be considered as possible antitumor agents in the osteosarcoma model of bone-related cells in culture.

We have proposed a new method which can be applied in assessing the intracellular production of hydrogen peroxide. Using this assay we have examined the hydrogen peroxide generation during the L-glutamate induced oxidative stress in the HT22 hippocampal cells. The detection of hydrogen peroxide is based on two crucial reagents cis-[Cr(C 2 O 4 )(pm)(OH 2 ) 2 ] + (pm denotes pyridoxamine) and 2-ketobutyrate. The results obtained indicate that the presented method can be a promising tool to detect hydrogen peroxide in biological samples, particularly in cellular experimental models.

1,3-Diphenylisobenzofuran (DPBF) has been developed as a selective probe for the detection and quantitative determination of hydrogen peroxide in samples containing different reactive nitrogen and oxygen species (RNOS). DPBF is a fluorescent probe which, for almost 20 years, was believed to react in a highly specific manner toward some reactive oxygen species (ROS) such as singlet oxygen and hydroxy, alkyloxy or alkylperoxy radicals. Under the action of these individuals DPBF has been rapidly transformed to 1,2-dibenzoylbenzene (DBB). In order to check if DPBF can act as a unique indicator of the total amount of different RNOS, as well as oxidative stress caused by an overproduction of these individuals, a series of experiments was carried out, in which DPBF reacted with peroxynitrite anion, superoxide anion, hydrogen peroxide, hypochlorite anion, and anions commonly present under biological conditions, namely nitrite and nitrate. In all cases, except for hydrogen peroxide, the product of the reaction is DBB. Only under the action of H 2 O 2 9-hydroxyanthracen-10(9H)-one (oxanthrone) is formed. This product has been identified with the use of fluorescence spectroscopy, NMR spectroscopy, high performance liquid chromatography coupled with mass spectrometry, infrared spectroscopy, elemental analysis, and cyclic voltammetry (CV). A linear relationship was found between a decrease in the fluorescence intensity of DPBF and the concentration of hydrogen peroxide in the range of concentrations of 0.196-3.941 mM. DPBF responds to hydrogen peroxide in a very specific way with the limits of detection and quantitation of 88 and 122.8 μM, respectively. The kinetics of the reaction between DBBF and H 2 O 2 was also studied.

The influence of the oxydiacetate (ODA) and thiodiacetate (TDA) ligands on the physicochemical and biological properties of the oxidovanadium(IV) ternary complexes of the VO(L)(B) type, where L denotes ODA or TDA and B denotes 2,2'-bipyridine (bipy) or 1,10-phenanthroline (phen), has been investigated. The stability of the complexes in aqueous solutions, assessed based on the potentiometric titration method, increases in the following direction: VO(TDA)(bipy) < VO(ODA)(bipy) < VO(TDA)(phen) < VO(ODA)(phen). Furthermore, the influence of the TDA and ODA ligands on the antioxidant activity of the oxidovanadium(IV) complexes toward superoxide free radical (O 2 •- ), 2,2'-azinobis(3-ethylbenzothiazoline-6 sulfonic acid) cation radical (ABTS +• ) and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH • ) has been examined and discussed. The reactivity of the complexes toward O 2 •- increases in the following direction: VO(TDA)(phen) < VO(TDA)(bipy) ≈ VO(ODA)(bipy) < VO(ODA)(phen). The antioxidant activity against ABTS +• and DPPH • free radicals is higher for phen complexes, whereas the thiodiacetate complexes are more reactive than are the corresponding oxydiacetate ones. Finally, herein, the cytoprotective activity of the complexes against the oxidative damage generated exogenously by hydrogen peroxide in the hippocampal neuronal HT22 cell line (the MTT and LDH tests) is reported. In a low concentration (1 μM), the cytoprotective action of thiodiacetate complexes is much higher than that of the corresponding oxydiacetate complexes. However, in the higher concentration range (10 and 100 μM), the antioxidant activity of the complexes is overcompensated by their cytotoxic effect.

Hydrogen peroxide is a well-established precursor of reactive oxygen and nitrogen species that are known to contribute to oxidative stress-the crucial factor responsible for the course of a wide range of phy-sicochemical processes as well as the genesis of various diseases, such as cancer and neurodegenerative disorders. Thus, the development of sensitive and selective methods for the detection and quantitative determination of hydrogen peroxide is of great importance in monitoring the in vivo production of that species and elucidating its biological functions. This review highlights the progress that has been made in the development of fluorescent and luminescent probes (excluding nanoparticles) employed to monitor hydrogen peroxide under biological conditions. Attention was focused on probes developed in the past 10 years.

Detection and quantitative determination in biological media of the hydroxyl radical are of great importance due to the role this radical plays in many physiological and pathological processes. This review focuses on the progress that has been made in recent years in the development of fluorescent and luminescent probes employed to monitor hydroxyl radical concentrations under biological conditions.

The aim of this work was to find a relationship between physicochemical properties of the oxovanadium(IV) complexes, namely [VO(ODA)(H2O)2], [VO(ODA)(phen)]·1.5H2O and [VO(ODA)(bipy)]·2H2O (ODA = oxydiacetate) as well as [VO(H2O)5](2+), and their biological activity. A potentiometric titration method has been used to characterize the stability of the complexes in aqueous solutions. Furthermore, the reactivity of the complexes towards superoxide free radicals was assessed by employing the NBT assay as well as a cyclic voltammetry (CV) technique. Additionally, the investigations of the antioxidant properties of the complexes were complemented by studying their reactivity towards organic radicals (the ABTS and DPPH tests). Finally, the biological properties of the complexes were investigated in relation to their cytoprotective activity against the oxidative damage generated exogenously by using hydrogen peroxide in the Hippocampal neuronal cell line HT22 (the MTT and LDH tests). The obtained results showed that all the compounds under study display antioxidant properties but a concentration-depended protective effect against the oxidative damage was found for [VO(ODA)(bipy)]·2H2O only.

The potentiometric and conductometric titration methods have been used to characterize the stability of series of VO(IV)-, Co(II)- and Ni(II)-oxydiacetato complexes in DMSO-water solutions containing 0-50 % (v/v) DMSO. The influence of DMSO as a co-solvent on the stability of the complexes as well as the oxydiacetic acid was evaluated. Furthermore, the reactivity of the complexes towards superoxide free radicals was assessed by employing the nitro blue tetrazolium (NBT) assay. The biological properties of the complexes were investigated in relation to their cytoprotective activity against the oxidative damage generated exogenously by using hydrogen peroxide in the Human Dermal Fibroblasts adult (HDFa) cell line as well as to their antimicrobial activity against the bacteria (Bacillus subtilis, Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis). The relationship between physicochemical and biological properties of the complexes was discussed.