Restoration of soils contaminated with PAHs by the mixture of zeolite composites mixed with exogenous organic matter and mineral salts.

The major cause of soil degradation (contamination, erosion, compaction) is closely linked to agriculture, i.e., unsustainable agriculture practices, which are reflected in the depletion of the soil organic carbon pool, loss in soil biodiversity, and reduction of C sink capacity in soils. Therefore, the agricultural practice of applying carbon-rich materials into the soil is an attractive solution for climate change mitigation and soil ecosystem sustainability. The paper aimed to evaluate the effectiveness of the addition of organic-mineral mixtures to the mineral salts (NPK), including the exogenous organic matter (lignite) mixed with zeolite-carbon (NaX-C) or zeolite-vermiculite (NaX-Ver) composites in the restoration of soils contaminated with PAHs. The addition of zeolite composites to fertilizer resulted in a significant reduction in soil PAH levels and a corresponding reduction in plant tissue content, without compromising yields, compared to the control and separate application of NPK. A Significant correlation between PAHs and pHH2O, pHKCl, EC and dehydrogenase activity (DhA) was found in soils. The addition of zeolite composites with lignite significantly reduced the content of PAHs in straws, especially following the application of NaX-C. However, in the case of grains, the highest percentage reduction in comparison to NPK was observed for the highest dose of NaX-Ver.

Effect of organic/inorganic composites as soil amendments on the biomass productivity and root architecture of spring wheat and rapeseed.

Organic and inorganic soil amendments are used to increase crop yields and fertilizer efficiency, as well as to improve the physical and biological properties of soil, increase carbon sequestration, and restore contaminated and saline soils. The present study aimed to evaluate the effect of various zeolite composites mixed with either lignite or leonardite on the biomass production of spring wheat and rapeseed and their root morphology. A pot experiment involved the application of the following treatments: zeolite-carbon, zeolite-vermiculite composites, both mixed with lignite or leonardite, and a control treatment with no amendments. Inorganic composites were applied in a dose of 3% and 6%. The study also included an analysis of the root morphometric parameters and aboveground biomass of spring wheat and rapeseed. The lowest productivity was observed when both crops were not enriched with fertilizers or other amendments, 24.92 g per pot and 29.83 g per pot for spring wheat and rapeseed, respectively. The application of mineral fertilizers in combination with zeolite-carbon composite gave the highest aboveground biomass of spring wheat, 110.11 g per pot. Both zeolite-carbon and zeolite-vermiculite composites modified the morphological parameters of roots, with the control treatment showing the lowest root length and dry matter. Although mineral fertilization was found to have a positive impact root development in relation to untreated control, the treatment amended with zeolite-carbon composite and leonardite exhibited the highest root length and biomass of spring wheat. No other soil amendments improved the properties of rapeseed roots.

Zeolite Composite Materials from Fly Ash: An Assessment of Physicochemical and Adsorption Properties.

Waste fly ash, with both low (with the addition of vermiculite) and high contents of unburned coal, were subjected to hydrothermal syntheses aiming to obtain zeolite composite materials-zeolite + vermiculite (NaX-Ver) and zeolite + unburned carbon (NaX-C). The composites were compared with parent zeolite obtained from waste fly ash with a low content of unburned carbon (NaX-FA). In this study, the physicochemical characteristics of the obtained materials were evaluated. The potential application of the investigated zeolites for the adsorption of ammonium ions from aqueous solutions was determined. Composite NaX-Ver and parent zeolite NaX-FA were characterized by comparable adsorption capacities toward ammonium ions of 38.46 and 40.00 mg (NH4+) g-1, respectively. The nearly 2-fold lower adsorption capacity of composite NaX-C (21.05 mg (NH4+) g-1) was probably a result of the lower availability of ion exchange sites within the material. Adsorbents were also regenerated using 1 M NaCl solution at a pH of 10 and subjected to 3 cycles of adsorption-desorption experiments, which proved only a small reduction in adsorption properties. This study follows the current trend of waste utilization (fly ash) and the removal of pollutants from aqueous solutions with respect to their reuse, which remains in line with the goals of the circular economy.

The pan-Bcl-2 inhibitor obatoclax promotes differentiation and apoptosis of acute myeloid leukemia cells.

One of the key features of acute myeloid leukemia (AML) is the arrest of differentiation at the early progenitor stage of myelopoiesis. Therefore, the identification of new agents that could overcome this differentiation block and force leukemic cells to enter the apoptotic pathway is essential for the development of new treatment strategies in AML. Regarding this, herein we report the pro-differentiation activity of the pan-Bcl-2 inhibitor, obatoclax. Obatoclax promoted differentiation of human AML HL-60 cells and triggered their apoptosis in a dose- and time-dependent manner. Importantly, obatoclax-induced apoptosis was associated with leukemic cell differentiation. Moreover, decreased expression of Bcl-2 protein was observed in obatoclax-treated HL-60 cells. Furthermore, differentiation of these cells was accompanied by the loss of their proliferative capacity, as shown by G0/G1 cell cycle arrest. Taken together, these findings indicate that the anti-AML effects of obatoclax involve not only the induction of apoptosis but also differentiation of leukemic cells. Therefore, obatoclax represents a promising treatment for AML that warrants further exploration.

Comparison of In Vitro Antileukemic Activity of 4-Hydroperoxyifosfamide and 4-Hydroperoxycyclophosphamide.

BACKGROUND/AIM: The oxazaphosphorines, ifosfamide and cyclophosphamide, represent a class of alkylating agents. The aim of the present in vitro study was to compare antileukemic activity of 4-hydroperoxyifosfamide (4-OOH-IF) and 4-hydroperoxycyclophosphamide (4-OOH-CP). MATERIALS AND METHODS: The experiments were performed on MOLT-4 and ML-1 cells. The research was conducted using flow cytometry fluorescein diacetate/propidium iodide (PI), fluorescein-conjugated annexin V/PI, CaspGLOW Red Active Caspase-8 and -9, CellEvent™ Caspase-3/7 Green assays, and tetramethylrhodamine ethyl ester test. RESULTS: 4-OOH-IF and 4-OOH-CP distinctly reduced cell viability and triggered apoptosis and necrosis, causing changes in intracellular esterase activity, plasma membrane structure and integrity, caspase activation, and mitochondrial membrane potential. The oxazaphosphorines were responsible for the different antileukemic activities. 4-Hydroperoxyifosfamide appeared to be less cytotoxic against the leukemia cells than 4-hydroperoxycyclophosphamide. MOLT-4 cells were more sensitive to the action of the oxazaphosphorines than ML-1 cells. CONCLUSION: The findings provide a new insight on the mechanisms of cytotoxic action of 4-OOH-IF and 4-OOH-CP on the human acute lymphoblastic and myeloblastic leukemia cells.

In Vitro Antileukemic Activity of Formamidine Epidoxorubicin Analogs.

BACKGROUND/AIM: Epidoxorubicin is an anthracycline agent. The present study was undertaken to compare the antileukemic potential of epidoxorubicin and its two formamidine analogs containing either a morpholine moiety (EPIFmor) or a hexamethyleneimine moiety (EPIFhex) in the amidine group. MATERIALS AND METHODS: The experiments were performed in vitro on MOLT-4 cells using spectrophotometry, Coulter electrical impedance, flow cytometry, and light microscopy methods. RESULTS: The leukemia cell responses to the action of the anthracyclines were manifested in their different viability, count and volume, degree of apoptosis and necrosis, activity of caspases -8, -9, and -3/7, mitochondrial membrane potential, and in the cell-cycle distribution. In general, epidoxorubicin appeared to be the most active, and EPIFmor was more active than EPIFhex against MOLT-4 cells. CONCLUSION: The structural modifications of epidoxorubicin in the amidine group were responsible for the varied action of its formamidine analogs on human acute lymphoblastic leukemia cells.

In Vitro Effects of Bromoalkyl Phenytoin Derivatives on Regulated Death, Cell Cycle and Ultrastructure of Leukemia Cells.

BACKGROUND/AIM: To search for new antileukemic agents, the chemical structure of phenytoin was modified. A possible cytotoxic activity of three bromoalkyl phenytoin analogs, methyl 2-(1-(3-bromopropyl)-2,4-dioxo-5,5-diphenylimidazolidin-3-yl) propanoate (PH2), 1-(3-bromopropyl)-3-methyl-5,5-diphenylimidazolidine-2,4-dione (PH3) and 1-(4-bromobutyl)-3-methyl-5,5-diphenylimidazolidine-2,4-dione (PH4) on regulated cell death, the cell cycle and cell ultrastructure was assessed. MATERIALS AND METHODS: The experiments were performed in vitro on HL-60 and U937 cells, using flow cytometry and electron microscopy methods. RESULTS: Application of PH2, PH3, and PH4 resulted in cell surface exposure of phosphatidylserine and plasma membrane impairment, caspase-8, -9, and -3/7 activation, dissipation of mitochondrial membrane potential, DNA breakage, cell-cycle disturbance and cell ultrastructural changes. In general, PH3 appeared to be the most active against the leukemia cells, and all bromoalkyl hydantoins, PH2-PH4, were more active in HL-60 cells than in U937 cells. CONCLUSION: The antileukemic activity of the bromoalkyl phenytoin analogs depended on the combination of N-hydantoin substituents and the human cell line used.

Combination of ABT-737 and resveratrol enhances DNA damage and apoptosis in human T-cell acute lymphoblastic leukemia MOLT-4 cells.

ABT-737 belongs to a new class of anticancer agents named BH3 mimetics. ABT-737 competitively binds to surface hydrophobic grooves of anti-apoptotic proteins of Bcl-2 family, counteracting their protective effect. Resveratrol is a natural polyphenol that has been shown to inhibit the proliferation and/or induce apoptosis in a number of different types of cancer cells. The present study was designed to analyze the combined effects of ABT-737 and resveratrol on human acute lymphoblastic leukemia cells. The in vitro cytotoxic activity of these agents against MOLT-4 leukemia cells was determined using the Coulter electrical impedance method, comet assay, and flow cytometry, light microscopy and western blot techniques. The results are the first data showing that ABT-737 combined with resveratrol markedly decreased the cell viability, increased DNA damage, caused the cell cycle perturbation, and synergistically enhanced apoptosis in MOLT-4 cells, when compared to the data obtained after application of the single agent. Moreover, the simultaneous treatment of leukemia cells with ABT-737 and resveratrol resulted in a reduction in mitochondrial membrane potential, an increase of p53 protein level and up-regulation of the Bax/Bcl-2 ratio. The obtained data indicate that the combination of ABT-737 and resveratrol is a promising approach for acute lymphoblastic leukemia treatment that should be further explored.

Comparison of in vitro antileukemic activity of obatoclax and ABT-737.

Obatoclax and ABT-737 belong to a new class of anticancer agents known as BH3-mimetics. These agents antagonize the anti-apoptotic members of Bcl-2 family. The Bcl-2 proteins modulate sensitivity of many types of cancer cells to chemotherapy. Therefore, the objective of the present study was to examine and compare the antileukemic activity of obatoclax and ABT-737 applied alone, and in combination with anticancer agent, mafosfamide and daunorubicin. The in vitro cytotoxic effects of the tested agents on human leukemia cells were determined using the spectrophotometric MTT test, Coulter electrical impedance method, flow cytometry annexin V-fluorescein/propidium iodide assay, and light microscopy technique. The combination index analysis was used to quantify the extent of agent interactions. BH3 mimetics significantly decreased the leukemia cell viability and synergistically enhanced the cytotoxic effects induced by mafosfamide and daunorubicin. Obatoclax affected the cell viability to a greater degree than did ABT-737. In addition, various patterns of temporary changes in the cell volume and count, and in the frequency of leukemia cells undergoing apoptosis, were found 24 and 48 h after the tested agent application. ABT-737 combined with anticancer agents induced apoptosis more effectively than obatoclax when given in the same combination regimen. The results of the present study point to the different antileukemic activities of obatoclax and ABT-737, when applied alone, and in combination with anticancer agents. A better understanding of the exact mechanisms of BH3 mimetic action is of key importance for their optional use in cancer therapy.

In vitro cytotoxic activity evaluation of phenytoin derivatives against human leukemia cells.

Hydantoin derivatives, including phenytoin (5,5-diphenylhydantoin), have recently gained attention as they possess a variety of important biochemical and pharmacological properties. Nevertheless, available information on anticancer activity of hydantoin derivatives is still scarce. Here, we evaluated possible antileukemic potential of four phenytoin analogs, namely: methyl 2-(2,4-dioxo-5,5-diphenylimidazolidin-3-yl)propanoate (1), methyl 2-(1-(3-bromopropyl)-2,4-dioxo-5,5-diphenylimidazolidin-3-yl)propanoate (2), 1-(3-bromopropyl)-3-methyl-5,5-diphenylimidazolidine-2,4-dione (3) and 1-(3-bromobutyl)-3-methyl-5,5-diphenylimidazolidine-2,4-dione (4). The experiments were performed on human acute histiocytic lymphoma U937 cells and human promyelocytic leukemia HL-60 cells. The present study was conducted using spectrophotometric 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay and the electronic Beckman-Coulter method. We observed temporary changes in the leukemia cell viability, volume and count. The effects of the four 5,5-diphenylhydantoin derivatives on U937 and HL-60 cells depended on the agent tested and its concentration, the time intervals after the compound application, and the leukemia cell line used. HL-60 cells were more sensitive than U937 cells to the action of the phenytoin analogs (1-4). The antileukemic activities of the three bromoalkyl diphenylhydantoin derivatives (2, 3, and 4) were stronger than that of the compound 1 [methyl 2-(2,4-dioxo-5,5-diphenylimidazolidin-3-yl) propanoate], with no bromoalkyl substituent. The structural modifications of 5,5-diphenylhydantoin are responsible for such varied antileukemic potential of its four derivatives.

Cell-cycle disturbance and induction of programmed death by new formamidine analogs of daunorubicin.

BACKGROUND/AIM: Structural modifications of daunorubicin are an important way to change its anticancer activity. For this reason, formamidinodaunorubicins have been synthesized. The present study was undertaken to determine and compare the in vitro effects of daunorubicin and its new formamidine derivatives on human acute leukemia MOLT-4 and ML-1 cells. MATERIALS AND METHODS: The experiments were performed on human acute lymphoblastic leukemia MOLT-4 cells and human acute myeloblastic leukemia ML-1 cells. The study was conducted using flow cytometry and light microscopy methods. RESULTS: The various patterns of temporary changes in the cell cycle and DNA fragmentation, as well as the extent of mitotic catastrophe, apoptosis, and necrosis, were determined. The anti-leukemic activities of the new daunorubicin analogs were weaker than that of daunorubicin. CONCLUSION: The influence of these anthracyclines on cell-cycle progression, DNA damage, and induction of mitotic catastrophe and cell death depended on the agent and its concentration, the time interval after application, and the cell line used. The structural modifications of daunorubicin were responsible for the different cytotoxic effects of the two formamidinodaunorubicins.

In vitro cytotoxicity testing of new generation oxazaphosphorines against human histiocytic lymphoma cells.

Oxazaphosphorines belong to a group of alkylating agents. Mafosfamide cyclohexylamine salt (D-17272), 4-hydro-peroxy-cyclophosphamide (D-18864) and glufosfamide (D-19575, beta-D-glucose-isophosphoramide mustard) are new generation oxazaphosphorines. The objective of the present study was to compare the cytotoxic action of these oxazaphosphorine compounds against human histiocytic lymphoma U937 cells. The chemical structures of the oxazaphosphorines were responsible for the different responses of U937 cells. The cytotoxic effects of D-17272, D-18864, and D-19575 on U937 cells depended on the agent tested, its dose, and the time intervals after the oxazaphosphorine application. Among the oxazaphosphorine agents, D-18864 appeared to be the most cytotoxic, and D-19575 was characterized by the lowest cytotoxicity. The in vitro cytotoxic activities of the oxazaphosphorines were strongly associated with their cell death inducing potential.

In vitro response of human pathological hematopoietic cells to cladribine.

The influence of cladribine (2-chloro-2'-deoxyadenosine, CdA) on in vitro response of human acute lymphoblastic leukemia MOLT-4 cells, human histiocytic lymphoma U-937 cells, and human promyelocytic leukemia HL-60 cells, was determined using the MTT spectrophotometric and Beckman Coulter methods. Cell viability, cell volume and count were compared 24h and 48h after cladribine application at four concentrations--50 nM, 100 nM, 250 nM, and 500 nM. Different patterns of temporary changes in the viability, volume and count of pathological hematopoietic cells exposed to the action of CdA were found. The effects of CdA on MOLT-4, U-937, and HL-60 cells were dependent on the agent tested and its concentration, the time intervals after agent application, and the cell line used. The various in vitro cytotoxic activities of CdA against the three human pathological hematopoietic cell lines were shown.

In vitro induction of apoptosis and necrosis by new derivatives of daunorubicin.

BACKGROUND/AIM: The comparative effects of daunorubicin, and its new formamidine derivatives containing either a morpholine moiety (DAUFmor) or a hexamethyleneimine moiety (DAUFhex) in the amidine group, on induction of programmed cell death were determined. MATERIALS AND METHODS: The experiments were performed on human acute lymphoblastic leukemia MOLT-4 cells and human acute myeloblastic leukemia ML-1 cells. The research was conducted using the flow cytometry annexin V-fluorescein (FITC)/propidium iodide (PI) method and tetramethylrhodamine ethyl ester (TMRE) assay. RESULTS: The various patterns of temporary changes of early apoptotic cells, late apoptotic and necrotic cells, and in the frequency of the acute leukemia cells with high values of mitochondrial membrane potential (MMP) were found. Phosphatidylserine externalization, plasma membrane disruption, and changes in MMP occurring in the leukemia cells were dependent on the agent tested, its concentration, the time intervals after daunorubicin, DAUFmor, and DAUFhex application, and on the leukemia cell line used. CONCLUSION: The structural modifications of daunorubicin producing two new analogs, DAUFmor and DAUFhex, induced the different responses of MOLT-4 and ML-1 cells to triggering of programmed death.

In vitro effects of new generation oxazaphosphorines on human promyelocytic leukemia cells.

Mafosfamide cyclohexylamine salt (D-17272), 4-hydro-peroxy-cyclophosphamide (D-18864) and glufosfamide (D-19575, beta-D-glucose-isophosphoramide mustard) are new generation oxazaphosphorine agents. The present investigation was undertaken to determine the activity of these three oxazaphosphorines in human promyelocytic leukemia HL-60 cells. The research was conducted using the spectrophotometric MTT assay and the electronic Beckman Coulter and microscopy methods. Functional and morphological changes were observed after exposure of HL-60 cells to the oxazaphosphorine agents. The various patterns of temporary alterations in cell viability, size and count, and also in the frequency of leukemic cells undergoing mitotic catastrophe, apoptosis and necrosis, were shown. Different leukemic cell responses to the action of the three oxazaphosphorines were evaluated. These are the first data comparing the in vitro activity of D-17272, D-18864 and D-19575 against human promyelocytic leukemia cells.

Effects of structural modifications of daunorubicin on in vitro antileukemic activity.

BACKGROUND/AIM: In the search for new derivatives of anthracycline antibiotics, formamidinodaunorubicins containing in the amidine group either a morpholine moiety (DAUFmor) or a hexamethyleneimine moiety (DAUFhex) were synthesized. The biological effects of daunorubicin (DAU), DAUFmor and DAUFhex were compared. MATERIALS AND METHODS: The experiments were performed on human acute lymphoblastic leukemia MOLT-4 cells and human acute myeloblastic leukemia ML-1 cells. The research was conducted using the spectrophotometric 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay and the electronic Beckman-Coulter method. RESULTS: Temporary changes in the leukemia cell viability, size and count were found. The antileukemic activities of the new DAU analogs were weaker than that of daunorubicin. MOLT-4 cells were more sensitive than ML-1 cells to the action of all agents. Among the formamidinodaunorubicins, DAUFmor appeared to be more active in ML-1 cells than DAUFhex, but there were not differences between the analyzed values in MOLT-4 cells. CONCLUSION: The structural modifications of daunorubicin were responsible for the different antileukemic potentials of the two formamidinodaunorubicins.

Mafosfamide as a new anticancer agent: preclinical investigations and clinical trials.

Mafosfamide (4-thioethane sulfonic acid salt of 4-hydroxy-cyclophosphamide, MAF) belongs to a new generation of the oxazaphosphorine agents. MAF is a cyclophosphamide analog which spontaneously degrades to 4-hydroxy-cyclophosphamide. The effects of MAF on various types of cancer cells were determined during preclinical investigations and clinical trials. The positive results from in vitro and in vivo anticancer studies promoted MAF to a good candidate for phase I trials. Clinical experience with intrathecal MAF, used for patients with neoplastic meningitis due to leukemia, lymphoma, and solid tumors, indicated good tolerability and efficacy. The recommended phase II doses of intrathecally administered MAF were determined. Clinical trials using intrathecal MAF are now underway. To obtain a better therapeutic index, a strategy to alternate dosing between the intraventricular and intralumbar routes is also being tested. MAF is an attractive agent for regional cancer therapy. The current available knowledge on MAF as a new anticancer agent is based on a collection of the original published studies, conference abstracts and relevant articles.

Comparative effects of new generation oxazaphosphorines on the size and viability of human acute myeloblastic leukemia cells.

Mafosfamide cyclohexylamine salt (D-17272), 4-hydro-peroxy-cyclophosphamide (D-18864), and beta-D-glucose-isophosphoramide mustard (D-19575, glufosfamide) are three new generation oxazaphosphorine agents. The aim of the present study was to compare the cell response to the action of these three oxazaphosphorines. The experiments were performed in vitro on human acute myeloblastic leukemia ML-1 cells. After exposure of ML-1 cells to the oxazaphosphorines, the size, viability and count of these cells were determined. The research was conducted using the spectrophotometric MTT assay and the electronic Beckman Coulter method. The temporary changes in the ML-1 cell size, viability and count, were dependent on the oxazaphosphorine agent tested, its dose, and the time intervals after its application. Among the three oxazaphosphorine agents, D-18864 proved to be the most cytotoxic, and D-19575 was characterized by the lowest cytotoxicity. The results suggest the possibility of using the electronic sizing and counting method and the MTT assay as a rapid in vitro test for assessing leukemic cell sensitivity to the action of new potential chemotherapeutic agents.

Glufosfamide as a new oxazaphosphorine anticancer agent.

Glufosfamide (ß-D-glucose-isophosphoramide mustard, D-19575) belongs to the oxazaphosphorine class. Glufosfamide is a novel glucose conjugate of ifosfamide in which isophosphoramide mustard, the alkylating metabolite of ifosfamide, is glycosidically linked to the ß-D-glucose molecule. Glufosfamide represents an attractive new agent for cancer therapy. Its mode of action on normal and pathological cells is still under experimental and clinical investigations. An assessment of the anticancer potential of glufosfamide is of key importance in therapy. The researchers reviewed the current knowledge available on glufosfamide tested in the preclinical studies/clinical trials, based on a collection of the original papers and conference abstracts published and relevant articles searched in the SCOPUS and MEDLINE database and websites.

Induction of DNA breakage in U937 cells by oxazaphosphorines.

Oxazaphosphorines are a class of DNA alkylating agents. The aim of the present study was to compare the possible influence of three new generation oxazaphosphorines, D-17272 (mafosfamide cyclohexylamine salt), D-18864 (4-hydro-peroxy-cyclophosphamide), and D-19575 (glufosfamide, beta-D-glucose-isophosphoramide mustard) on DNA damage induction in the human histiocytic lymphoma U937 cells. The flow cytometry APO-BRDU assay, based on the TUNEL method, was used for the in situ detection of DNA strand breaks. After exposure of U937 cells to the oxazaphosphorines, the patterns of temporary changes in the frequency of TUNEL positive U937 cells, expressing DNA breakage, were determined. The effects of the oxazaphosphorines on U937 cells were dependent on the agent tested and its dose, and the time intervals after the drug application. The different potential of D-17272, D-18864 and D-19575 to induce DNA strand breakage in the human histiocytic lymphoma U937 cells was shown.