Trace metals and polycyclic aromatic hydrocarbons in the Eastern Mediterranean sediments: Concentration ranges as a tool for quality control of large data collections.

Assessing the status of marine pollution at regional and sub-regional scales requires the use of comparable and harmonized data provided by multiple institutions, located in several countries. Standardized data management and quality control are crucial for supporting a coherent evaluation of marine pollution. Taking the Eastern Mediterranean Sea as a case study, we propose an approach to improve the quality control procedures used for sediment pollution data, thus supporting a harmonized environmental assessment. The regional ranges of contaminant concentrations in sediments were identified based on an in-depth literature review, and the lowest measured concentrations were evaluated to determine the "background concentrations" of chemical substances not yet targeted in the Mediterranean Sea. In addition, to verify the suitability of the approach for validating large data collections provided by multiple sources, the determined ranges were used to validate a regional dataset available through EMODnet data infrastructure.

Measuring pharmacovigilance knowledge and attitudes among healthcare sciences students: development and validation of a universal questionnaire.

OBJECTIVE: Pharmacovigilance education and reporting of adverse drug reactions (ADRs) are important competencies that healthcare sciences students should develop before completing their studies and entering clinical practice. Since students frequently lack adequate knowledge in this area and fail to recognize the importance of ADRs monitoring and reporting, the aim of this study was to develop and validate a unique and reliable instrument for assessing health sciences students' knowledge and attitudes toward pharmacovigilance and ADRs reporting. SUBJECTS AND METHODS: A cross-sectional observational study was conducted from February to July 2021 to examine students' knowledge and attitudes toward pharmacovigilance activities. Students of medicine, dentistry, pharmacy, and nursing science of three faculties in the Autonomous Province of Vojvodina, Serbia were examined. A total of 211 of them completed the specially designed, three-section questionnaire (Demographic data section, Pharmacovigilance Knowledge test, PVKT, and Pharmacovigilance Attitude Questionnaire, PVAQ). The questionnaire was posted on the Google Forms platform, and the link was distributed to respondents via the official websites and social networks of all three faculties. RESULTS: Findings demonstrated good psychometric properties and reliability of the questionnaire. Six questions were removed from the PVKT after item analyses. After excluding these items, the calculated ordinal alpha of the final version of the PVKT, which included 14 items, was good (αord = 0.83), as were other statistical indicators. PVAQ reliability testing also revealed great performance of this questionnaire-calculated ordinal alpha for two PVAQ subscales was excellent (αord = 0.91, for both scales). CONCLUSIONS: This questionnaire has favorable validity and reliability in assessing healthcare sciences students' knowledge and attitudes toward pharmacovigilance and ADRs reporting.

In vitro antiproliferative study of novel adamantyl pyridin-4-ones.

The preparation of several N-aryl-substituted (phenyl, p-methylphenyl, p-methoxyphenyl, p-nitrophenyl, p-aminophenyl, p-hydroxyphenyl) 3-hydroxy-2-methylpyridin-4-ones as well as their adamantyl derivatives is described, and their in vitro antitumor properties were investigated. The compounds were synthesized in good yields using efficient synthetic routes and methods. Prepared derivatives were evaluated in an antiproliferative in vitro study on 4 cancer cell lines, namely HCT 116 (colon carcinoma), H 460 (lung carcinoma), MCF-7 (breast carcinoma) and K562 (chronic myelogenous leukemia). All tested compounds showed antiproliferative activity ranging from moderate to strong on all inspected cell lines with 4 adamantane containing derivatives being active and selective at low micromolar IC[Formula: see text] concentrations on HCT 116, H 460 and MCF-7. LDH cytotoxicity assay revealed that cytotoxic effects occur after 48 h of exposure. It was shown that there was no change in caspase activity in the treated cells, but there were changes in the cell cycle. All treated samples showed reduced number of cells in the S phase with increased G0/G1 (4b, 5a, 5b) and G2/M (4a) phase.

Novel urea and bis-urea primaquine derivatives with hydroxyphenyl or halogenphenyl substituents: Synthesis and biological evaluation.

A series of novel compounds 3a-j and 6a-j with primaquine and hydroxyl or halogen substituted benzene moieties bridged by urea or bis-urea functionalities were designed, synthesized and evaluated for biological activity. The title compounds were prepared using benzotriazole as the synthon, through several synthetic steps. 3-[3,5-Bis(trifluoromethyl)phenyl]-1-{4-[(6-methoxyquinolin-8-yl)amino]pentyl}urea (3j) was the most active urea and 1-[({4-[(6-methoxyquinolin-8-yl)amino]pentyl}carbamoyl)amino]-3-[3-(trifluoromethyl)phenyl]urea (6h) the most active bis-urea derivative in antiproliferative screening in vitro against eight tested cancer cell lines. Urea derivatives 3a-g with hydroxy group or one halogen atom showed moderate antiproliferative effects against all the tested cell lines, but stronger activity against breast carcinoma MCF-7 cell line, while trifluoromethyl derivatives 3h-j showed antiproliferative effects against all the tested cell lines in low micromolar range. Finally, bis-ureas with hydroxy and fluoro substituents 6a-d showed extreme selectivity and chloro or bromo derivatives 6e-g high selectivity against MCF-7 cells (IC50 0.1-2.6 µM). p-Fluoro derivative 6d, namely 3-(4-fluorophenyl)-1-[({4-[(6-methoxyquinolin-8-yl)amino]pentyl}carbamoyl)amino]urea, is the most promising compound. Further biological experiments showed that 6d affected cell cycle and induced cell death of MCF-7 cell line. Due to its high activity against MCF-7 cell line (IC50 0.31 µM), extreme selectivity and full agreement with the Lipinski's and Gelovani's rules for prospective small molecular drugs, 6d may be considered as a lead compound in development of breast carcinoma drugs. Urea 3b and almost all bis-ureas showed high antioxidant activity in DPPH assay, but urea derivatives were more active in lipid peroxidation test. Only few compounds exhibited weak inhibition of soybean lipoxygenase. Compound 3j exhibited the strongest antimicrobial activity in susceptibility assay in vitro (MIC = 1.6-12.5 µg ml-1).

Novel semicarbazides and ureas of primaquine with bulky aryl or hydroxyalkyl substituents: synthesis, cytostatic and antioxidative activity.

Novel primaquine semicarbazides 7a-l and ureas 9a-g with modified benzhydryl, trityl, phenyl or hydroxyalkyl substituents were prepared and evaluated for cytostatic and antioxidative activities. Two synthetic approaches for preparation of the title semicarbazides were applied, both having certain advantages. In the first approach, the products grew from the semicarbazide side and the primaquine residue entered the molecule the last. In the second approach, semicarbazide grew from the primaquine side. This method was more convenient for synthesis of a series of semicarbazides: various products could be obtained from the same precursor N-(4-((6-methoxyquinolin-8-yl)amino)pentyl)hydrazinecarbox-amide (10). Primaquine ureas 9a-f were prepared from primaquine benzotriazolide 8 and corresponding amines and urea 9g directly from primaquine and 4-chloro-3-(fluoromethyl)phenyl isocyanate. All primaquine semicarbazide derivatives showed either prominent cytostatic activity towards all the tested cell lines (benzhydryl or trityl derivatives 7a-e) or high selectivity towards MCF-7 cells (hydroxyalkyl derivatives 7h-l), with IC50 values in the low micromolar range. The highest selectivity exerted symmetric bisprimaquine derivative 7f, with an IC50 0.2 µM against MCF-7 cells and practically no activity against other seven tested cancer cell lines. Urea derivatives 9a-f were generally less active than their semicarbazide analogues, but still selective towards MCF-7 cells. Urea 9g with the similar structure to cytostatic drug sorafenib, was the most active urea derivative. Semicarbazides 7g and 10 showed the best antioxidative activity as measured by DPPH (64% at 20 min and 90% at 60 min), while urea derivatives 9a-g, especially 9d, and semicarbazides 7a-g with lipophilic substituents exerted better LP antioxidant activity. Both semicarbazides and ureas with methoxy or chloro benzhydryl substituents and high Clog P values showed significant LOX inhibition.

The mechanism of caesium intercalation of graphene.

Properties of many layered materials, including copper- and iron-based superconductors, topological insulators, graphite and epitaxial graphene, can be manipulated by the inclusion of different atomic and molecular species between the layers via a process known as intercalation. For example, intercalation in graphite can lead to superconductivity and is crucial in the working cycle of modern batteries and supercapacitors. Intercalation involves complex diffusion processes along and across the layers; however, the microscopic mechanisms and dynamics of these processes are not well understood. Here we report on a novel mechanism for intercalation and entrapment of alkali atoms under epitaxial graphene. We find that the intercalation is adjusted by the van der Waals interaction, with the dynamics governed by defects anchored to graphene wrinkles. Our findings are relevant for the future design and application of graphene-based nano-structures. Similar mechanisms can also have a role for intercalation of layered materials.

Novel NSAID 1-acyl-4-cycloalkyl/arylsemicarbazides and 1-acyl-5-benzyloxy/hydroxy carbamoylcarbazides as potential anticancer agents and antioxidants.

The novel 1-acyl-4-cycloalkyl/arylsemicarbazides (5a-y) and 1-acyl-5-benzyloxy/hydroxycarbamoylcarbazides (8a-f) derived from the nonsteroidal anti-inflammatory drugs ibuprofen, fenoprofen and reduced ketoprofen were prepared, fully chemically characterized and evaluated for their cytostatic, antiviral and antioxidant activities. Compounds 5 and 8 consist of a region rich in electronegative atoms (five to nine nitrogen and oxygen atoms) framed by aryl or cycloalkyl residues on one or both terminal ends. The synthetic pathways applied for the preparation of the title compounds involved a benzotriazole as a synthetic auxiliary in several steps. Three of the tested compounds, namely 4-benzhydryl-1-[2-(3-phenoxyphenyl)propanoyl]semicarbazide (5l), 4-benzhydryl-1-[2-(3-benzylphenyl)propanoyl]semicarbazide (5s), and 4-benzhydryl-1-[2-(4-isobutylphenyl)propanoyl]semicarbazide (5f) showed pronounced antiproliferative activity in vitro against six cancer cell lines (IC(50)=3-23 µM). The same compounds highly inhibited soybean lipoxygenase (IC(50)=60 and 51.5 µM) and lipid peroxidation as well (99, 88 and 74%, respectively). 4-Benzyloxy-1-[2-(4-isobutylphenyl)propanoyl]semicarbazide (5t) and 5-benzyloxycarbamoyl-1-[2-(3-benzylphenyl)propanoyl]carbazide (8c) exerted complete lipid peroxidation inhibition. Semicarbazides 5w-y and carbazides 8d-f bearing a hydroxamic acid/hydroxyurea moiety showed a modest antiradical activity in DPPH test, while the best radical scavenger was 1-(1-benzotriazolecarbonyl)-4-benzyloxysemicarbazide (7). None of the compounds were inhibitory to a broad panel of DNA and RNA viruses in the cell culture at subtoxic concentrations.

Photoemission and density functional theory study of Ir(111); energy band gap mapping.

We have performed combined angle-resolved photoemission spectroscopy (ARPES) experiments and density functional theory (DFT) calculations of the electronic structure of the Ir(111) surface, with the focus on the existence of energy band gaps. The investigation was motivated by the experimental results suggesting Ir(111) as an ideal support for the growth of weakly bonded graphene. Therefore, our prime interest was electronic structure around the [Formula: see text] symmetry point. In accordance with DFT calculations, ARPES has shown a wide energy band gap with the shape of a parallelogram centred around the [Formula: see text] point. Within the gap three surface states were identified; one just below the Fermi level and two spin-orbit split surface states at the bottom of the gap.

Computational structure-activity study directs synthesis of novel antitumor enkephalin analogs.

The capability of a Support Vector Machines QSAR model to predict the antiproliferative ability of small peptides was evaluated by screening a virtual library of enkephalin-like analogs modified by incorporation of the (R,S)-(1-adamantyl)glycine (Aaa) residue. From an initial set of 390 compounds, the peptides, Tyr-Aaa-Gly-Phe-Met (2), Tyr-Aaa-Gly-Phe-Phe (3), Phe-Aaa-Gly-Phe-Phe (4) and Phe-Aaa-Gly-Phe-Met (5) were selected, synthesized and their antitumor activity was tested and compared to that of Met-enkephalin (1). The antiproliferative activity correlated with the computational prediction and with the foldamer-forming ability of the studied peptides. The most active compounds were the hydrophobic peptides, Phe-Aaa-Gly-Phe-Phe (4) and Phe-Aaa-Gly-Phe-Met (5), having a greater propensity to adopt folded structures than the other peptides.

Urea and carbamate derivatives of primaquine: synthesis, cytostatic and antioxidant activities.

The novel urea primaquine derivatives 3 were prepared by aminolysis of primaquine benzotriazolide 2 with several hydroxyamines and ethylendiamine, while carbamates 4 were synthesized from the same precursor 2 and alcohols. All compounds are fully chemically characterized and evaluated for their cytostatic and antioxidant activities. The most prominent antiproliferative activity was obtained by compounds 3c, 3d, 3g, and 5b (IC(50)=9-40 microM). 1-(5-Hydroxypentyl)-3-[4-(6-methoxy-quinolin-8-ylamino)-pentyl]urea (3c) showed extreme selectivity toward SW 620 colon cancer cells (IC(50)=0.2 microM) and a bit less toward lung cancer cells H 460. Hydroxyurea 3h showed the highest interaction with DPPH. Primaquine twin drug 3g showed very significant inhibition on LOX soybean (IC(50)=62 microM). Almost all the tested derivatives highly inhibited lipid peroxidation, significantly stronger than primaquine phosphate.

Dirac cones and minigaps for graphene on Ir(111).

Epitaxial graphene on Ir(111) prepared in excellent structural quality is investigated by angle-resolved photoelectron spectroscopy. It clearly displays a Dirac cone with the Dirac point shifted only slightly above the Fermi level. The moiré resulting from the overlaid graphene and Ir(111) surface lattices imposes a superperiodic potential giving rise to Dirac cone replicas and the opening of minigaps in the band structure.

The novel phosphoramidate derivatives of NSAID 3-hydroxypropylamides: synthesis, cytostatic and antiviral activity evaluations.

The target phosphoramidates 5a-e were prepared in one step from 3-hydroxypropyl derivatives 3a-e of nonsteroidal anti-inflammatory drugs (fenoprofen, ketoprofen, ibuprofen, indomethacin, diclofenac). The products 3a-e and 5a-e were evaluated for their cytostatic and antiviral activity against malignant tumour cell lines and normal human fibroblasts (WI 38). All phosphoramidate derivatives 5a-e possess significantly greater inhibitory activities than the corresponding 3-hydroxypropyl derivatives 3a-e, whereby compound 5a showed the most potent inhibitory activities against cervical, pancreatic and colon carcinoma cell lines (IC(50)=5-7 microM).

A dual role of p21waf1/cip1 gene in apoptosis of HEp-2 treated with cisplatin or methotrexate.

We investigated the effects of p21(waf1/cip1) gene overexpression in human laryngeal squamous carcinoma cells HEp-2 lacking p53 protein expression on apoptosis induction upon the treatment with two commonly used chemotherapeutic agents, cisplatin and methotrexate. For that purpose, we employed cDNA arrays and qPCR to monitor gene expression upon treatment with AdCMV-p21 alone or in combination with the chemotherapeutic compounds. We found that p21(waf1/cip1) gene overexpression provoked apoptosis of HEp-2 through the induction of the TNFRSF9 gene and activation of caspase 7. In addition, we have proved that p21(waf1/cip1) can assume a dual role in apoptosis in the same cell system depending on the chemotherapeutic agent: its overexpression enhances apoptosis in cisplatin-treated cells and attenuates apoptotic signals in methotrexate-treated cells. The observed dual role of p21(waf1/cip1) was in direct correlation with the modulation of caspases 3 and 7 activation and changes in the expression of GADD45a gene. The results presented herein encourage future use of targeted p21(waf1/cip1) gene therapy in cancer treatment in a well-defined therapeutic and genetic context.

The novel primaquine derivatives of N-alkyl, cycloalkyl or aryl urea: synthesis, cytostatic and antiviral activity evaluations.

The novel urea primaquine derivatives 3a-i were prepared by aminolysis of benzotriazolide 2 with the corresponding amine in the presence or absence of triethylamine. Compound 2 was prepared by acylation of primaquine with 1-benzotriazole carboxylic acid chloride. Among all compounds evaluated, the pyridine derivative 3h exhibited the best cytostatic activities against colon carcinoma, human T-lymphocyte and murine leukemia. However, this compound showed also rather marked cytotoxicity towards human normal fibroblasts. The highest selectivity in the inhibitory effects on human malignant tumor cell lines vs. normal fibroblasts was found for ureas 3c, 3d and 3g. Results of broad antiviral evaluation showed that pyridine and phenethyl derivatives of urea 3h and 3g exhibited some selective inhibition against cytomegalovirus.

Comparison of photocatalysis and photolysis of malathion, isomalathion, malaoxon, and commercial malathion--products and toxicity studies.

Malathion, one of the most widely applied insecticides, is still used in agriculture. There are many studies regarding its degradation under different experimental conditions, but few deal with its transformation products, i.e. malaoxon and isomalathion. Thus, malathion, malaoxon, isomalathion, and Radotion (one of its over 6000 commercial forms) were studied in terms of their degradation kinetics, identification of their transformation products, their toxicity, and their degree of mineralization, during UV photolysis (lambda = 254 nm) and TiO(2) photocatalysis (lambda = 355 nm). The degradation kinetics was similar for all four starting materials. More than 75% of theoretically expected sulfur in PS and P-S groups was oxidized after 240 min of photolysis and photocatalysis. On the other hand, less than 30% of stoichiometrically predicted amounts of phosphate was detected in the photolytic experiments, but more than 80% of expected phosphate was detected after photocatalytic treatment of all four organophosphorous materials. Several transformation products were identified by mass spectra of representative gas chromatographic peaks. Oxidation and isomerization were found as the main reactions of butenedioc acid diethyl esters and their analogs. The formation of malaoxon, isomalathion or trimethyl phosphate esters correlated well with the induced toxicity (inhibition of acetylcholinesterase), which was observed in photocatalysis of malathion and Radotion, and in photolysis of malaoxon and Radotion.

Photodegradation of organophosphorus insecticides - investigations of products and their toxicity using gas chromatography-mass spectrometry and AChE-thermal lens spectrometric bioassay.

Four organophosphorus compounds: azinphos-methyl, chlorpyrifos, malathion and malaoxon in aqueous solution were degraded by using a 125 W xenon parabolic lamp. Gas chromatography-mass spectrometry (GC-MS) was used to monitor the disappearance of starting compounds and formation of degradation products as a function of time. AChE-thermal lens spectrometric bioassay was employed to assess the toxicity of photoproducts. The photodegradation kinetics can be described by a first-order degradation curve C=C0e(-kt), resulting in the following half lives: 2.5min for azinphos-methyl, 11.6 min for malathion, 13.3 min for chlorpyrifos and 45.5 min for malaoxon, under given experimental conditions. During the photoprocess several intermediates were identified by GC-MS suggesting the pathway of OP degradation. The oxidation of chlorpyrifos results in the formation of chlorpyrifos-oxon as the main identified photoproduct. In case of malathion and azinphos-methyl the corresponding oxon analogues were not detected. The formation of diethyl (dimethoxy-phosphoryl) succinate in traces was observed during photodegradation of malaoxon and malathion. Several other photoproducts including trimethyl phosphate esters, which are known to be AChE inhibitors and 1,2,3-benzotriazin-4(3H)-one as a member of triazine compounds were identified in photodegraded samples of malathion, malaoxon, and azinphos-methyl. Based on this, two main degradation pathways can be proposed, both result of the (P-S-C) bond cleavage taking place at the side of leaving group. The enhanced inhibition of AChE observed with the TLS bioassay during the initial 30 min of photodegradation in case of all four OPs, confirmed the formation of toxic intermediates. With the continuation of irradiation, the AChE inhibition decreased, indicating that the formed toxic compounds were further degraded to AChE non-inhibiting products. The presented results demonstrate the importance of toxicity monitoring during the degradation of OPs in processes of waste water remediation, before releasing it into the environment.

Synthesis and in vitro antitumor effect of diclofenac and fenoprofen thiolated and nonthiolated polyaspartamide-drug conjugates.

This paper reports the synthesis and antiproliferative effects of new thiomer-diclofenac and fenoprofen conjugates, hydrophilic, bioadhesive, polymeric prodrugs, as well as antiproliferative effects of diclofenac, fenoprofen and a series of previously described polymer-fenoprofen conjugates on five tumor cell lines. Thiolated and nonthiolated polyaspartamides were the chosen polymeric components. Drug-loading ranged from 5.6 to 22.4%, and the amount of SH groups ranged from 6.9 to 45.6micromol g(-1). Tensile studies demonstrated a clear correlation between the amount of thiol and the mucoadhesive properties of the conjugates. The growth-inhibitory activity of the tested polymer-drug conjugates demonstrates that polyaspartamide-type polymers, especially thiolated polymers, enable inhibition of tumor cell growth with significantly lower doses of the active substance.

Synthesis of phenanthridinium-bis-nucleobase conjugates, interactions with poly U, nucleotides and in vitro antitumour activity of mono- and bis-nucleobase conjugates.

Novel bis-nucleobase-phenanthridinium conjugates were synthesised and their aqueous solutions spectroscopically characterised. Bis-adenine conjugate revealed in aqueous solutions significantly more pronounced intramolecular aromatic stacking interactions than bis-uracil analogue. In contrast with previously reported poly A recognition by bis-uracil conjugate, recognition of complementary nucleotides and poly U was not observed due to the strong interference of bulk water with hydrogen bonding between nucleobases. The screening of anticancer activity on six human cell lines revealed that tethering of a nucleobase to phenanthridinium moiety diminished antiproliferative potential of phenanthridinium. However, among mono-nucleobase conjugates adenine derivative was found to be the most selective one (MiaPaCa-2, Hep-2).

Natural zeolite clinoptilolite: new adjuvant in anticancer therapy.

Natural silicate materials, including zeolite clinoptilolite, have been shown to exhibit diverse biological activities and have been used successfully as a vaccine adjuvant and for the treatment of diarrhea. We report a novel use of finely ground clinoptilolite as a potential adjuvant in anticancer therapy. Clinoptilolite treatment of mice and dogs suffering from a variety of tumor types led to improvement in the overall health status, prolongation of life-span, and decrease in tumors size. Local application of clinoptilolite to skin cancers of dogs effectively reduced tumor formation and growth. In addition, toxicology studies on mice and rats demonstrated that the treatment does not have negative effects. In vitro tissue culture studies showed that finely ground clinoptilolite inhibits protein kinase B (c-Akt), induces expression of p21WAF1/CIP1 and p27KIP1 tumor suppressor proteins, and blocks cell growth in several cancer cell lines. These data indicate that clinoptilolite treatment might affect cancer growth by attenuating survival signals and inducing tumor suppressor genes in treated cells.

Effect of the nonsteroidal anti-inflammatory drug indomethacin on proliferation and apoptosis of colon carcinoma cells.

PURPOSE: Nonsteroidal anti-inflammatory drugs lower the incidence of and mortality from colon cancer. In this paper, we present the effect of indomethacin on growth inhibition and alterations in the expression of several genes involved in cell cycle and apoptosis in CaCo-2 colon adenocarcinoma cells. METHODS: We used the MTT test to evaluate the effect of indomethacin on the proliferation rate of colon cancer and normal fibroblast cells in vitro. The expression of c-myc oncoprotein and p53 and p27 suppressor proteins was examined using the immunocytochemical method. RESULTS: We have shown that indomethacin reduces the proliferation rate of CaCo-2 colon cancer cells (up to 60% at the concentration of 4 x 10(-4) M), alters their morphology, and induces cell death by apoptosis. The most pronounced inhibitory effect was observed at the concentration of 6 x 10(-4) M where the growth was completely suppressed. However, the growth of normal fibroblasts (Hef 522) was much less inhibited (about 30% of inhibition at the concentration of 6 x 10(-4) M). Indomethacin reduces the proliferation rate and induces apoptosis in CaCo-2 colon cancer cells through enhanced expression of c-myc, p53, and p27 proteins. CONCLUSIONS: This is the first report about p27-increased expression in colon carcinoma cells induced by indomethacin treatment. Increased expression of p27 represents a new mechanism of apoptosis in cells treated with NSAIDs (indomethacin). This effect probably contributes to the anti-proliferative effect on colon cancer cells in vitro.