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Copyright of Romanian Journal of Materials / Revista Romana de Materiale is the property of Foundation for Materials Science & Engineering Serban Solacolu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The interactions of actinomycin D (ActD) anticancer drug with two bile salts of different hydrophobicity (sodium cholate (NaC) and sodium deoxycolate (NaDC) and the influence of these bile salts aggregates on the ActD–DNA complex was investigated in 10 mM phosphate buffer (pH 7.4) by UV–Vis spectroscopy (absorption and thermal denaturation). The binding strength of ActD to NaDC is higher than for NaC, and this difference attests stronger hydrophobic interactions between ActD and NaDC micelles. Also, the partition coefficient is significantly higher for NaDC micelles than for NaC micelles, in line with larger aggregates formed by NaDC. The spectral profile of ActD molecules in NaC and NaDC micelles, in comparison with different solvents, implies that ActD molecule experiences a hydrophobic environment in bile salts aggregates. Regarding the influence of NaC and NaDC aggregates on the ActD–DNA complex, it was shown that the presence of both bile salts micelles do not induce the deintercalation of ActD molecules from DNA duplex.

Crucial to the performance of devices based on organic molecules is an understanding of how the substrate-molecule interface influences both structural and electronic properties of the molecular layers. Within this context we studied the self-assembly of an alkoxy-triphenylene derived electron donor (HAT) in the monolayer regime on graphene/Ni(111). The molecules assembled into a close-packed hexagonal network commensurate with the graphene layer. Despite the commensurate structure, the HAT molecules only had a weak, physisorptive interaction with the substrate as pointed out by the photoelectron spectroscopy data. We discuss these findings in view of our recent reports for HAT adsorbed on Ag(111) and graphene/Ir(111). For all three substrates HAT adopts a similar close-packed hexagonal structure commensurate with the substrate while being physisorbed. The ionization potential is equal for all three substrates, supporting weak molecule-substrate interactions. These findings are remarkable, as commensurate overlayers usually only form at strongly interacting interfaces. We discuss potential reasons for this particular behavior of HAT which clearly sets itself apart from most studied molecule-substrate systems. In particular, these are the relatively weak but flexible intermolecular interactions, the molecular symmetry matching that of the substrate, and the comparatively weak but directional molecule-substrate interactions., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Association behavior between quinizarin (1,4-dihydroxyanthraquinone), an analogue of the chromophore of anthracycline anticancer drugs and sodium dodecyl sulfate (SDS) micelles in the presence of glucose, NaCl and urea additives was studied using absorption spectroscopy and conductometric techniques. The spectral results indicate an increase of binding constant and partition coefficient values in the presence of glucose and NaCl whereas the addition of urea leads to a decrease of binding strength and quinizarin partitioning into SDS micelles. Thus, the rise of NaCl and glucose concentrations is favorable for the quinizarin distribution into SDS micelles. From electrical conductivity measurements it was found that the critical micelle concentration (CMC) of SDS/quinizarin system decreases by adding NaCl and glucose whereas urea has not influence on the micelization process at the concentrations used in the present study. Since biologically compounds like glucose, NaCl and urea are found in the human body, the attained outcomes can be important in finding of effective drug delivery systems.

Introduction: The interest in the field of organ transplantation and the first attempts at making experimental transplant interventions in Romania date from the very beginning of the 20th century. Nevertheless, the evolution of the donating activity and of organ transplantation in Romania has been confronted with a certain inconsistency and a lack of resources necessary to the development of the system., Method: The aim of this study is to analyze the dynamics of the transplantation activity in Romania between 2000 and 2020. The study was accomplished through the analysis of available data corresponding to the above-mentioned period, which were published in the database of the National Transplant Agency, Eurostat and the Global Observatory on Donation and Transplantation. The data were processed using the MedCalc Statistical Software, version 14.8.1 (MedCalc Software bvba, Ostend, Belgium; http://www.medcalc.org; 2014)., Results: The activity of donation and organ transplantation in Romania has been maintained at a low level, with a rate of 3.44 donators pmp and a transplantation rate of 12.55 pmp, as reported for the year 2020. Romania remains at a transplantation rate of under 6.6 pmp, despite the considerable increase in the number of patients on the waiting lists, a fact which describes the picture of a relatively weak system, incapable of providing surgical interventions to cover the minimum needs that emerge within a calendar year., Conclusions: Our study points to the fact that the transplantation system in Romania is confronted with a major deadlock. Romania holds the last-but-one place in the ranking of countries in the European Union on transplant activity. The major impediment is the donation rate, which continues to be way below the European average, in a society where the awareness of the necessity to donate is very low, bureaucracy is cumbersome and there is a high degree of mistrust in the medical system, where the equipment is lacking and the infrastructure is incapable of providing services adapted to the modern standards.

ZnSe, ZnSe-TiO 2 microspheres and nanostructured TiO 2 obtained by hydrothermal and sol-gel methods were tested against Staphylococcus aureus ATCC 25923 and Micrococcus lysodeikticus ATCC 4698 before and after lysozyme (Lys) loading. Morphological characterization of inorganic matrices and hybrid organic-inorganic complexes were performed by microscopy techniques (SEM, AFM and Dark Field Hyperspectral Microscopy). Light absorption properties of ZnSe, ZnSe-TiO 2 and TiO 2 powders were assessed by UV-visible spectroscopy and their ability to generate reactive oxygen species (•OH and O 2 •- ) under visible light irradiation was investigated. Antibacterial activity of ZnSe, ZnSe-TiO 2 , TiO 2 , Lys/ZnSe, Lys/ZnSe-TiO 2 and Lys/TiO 2 samples under exposure to visible light irradiation (λ > 420 nm) was tested against Staphylococcus aureus and Micrococcus lysodeikticus and correlated with ROS photogeneration.

BACKGROUND Despite significant improvements in Romania's transplantation system, actual donor numbers have paradoxically fallen, contrary to the European trend. With a donation rate of 3.44 donors per million inhabitants, Romania ranks near the bottom of European countries. This study aimed to identify several predictors of a positive attitude toward organ donation in the Romanian population that could aid in reshaping public policies to improve donation and transplantation rates. MATERIAL AND METHODS The study included a representative Iasi population. Data were collected by means of a questionnaire focused on revealing attitudes toward organ donation, importance of consent, willingness to donate a family member's organs, and role of medical staff in the donation decision. A perception score was calculated as a methodological approach to validate attitudes toward organ donation. RESULTS Of all respondents, 55% agreed to donate their organs if declared brain-dead, while 20% opposed this idea; 72.7% considered consent necessary; 70% believed that consent must belong to the family when it comes to brain-dead organ donors; and 44.5% supported the idea of financial compensation. Higher monthly income was correlated with a positive attitude toward organ donation. CONCLUSIONS Even though the study population had a positive attitude toward organ donation, the willingness to donate was lower than in other European countries and did not translate into actual donations. The necessity of informed consent, lack of knowledge on the topic, bureaucratic aspects, and openness to financial compensation could explain the current situation of the Romanian transplantation system.

Background and Objectives: Hadjr El Melh of Djelfa is an example of hypersaline ecosystems, which can harbor a wide variety of microorganisms under hostile physicochemical conditions. Given the importance of the study of halophilic microorganisms present there in terms of fundamental and applied microbiology, the purpose of this study was to characterize some halophilic archaea isolated from the brines of this environment., Materials and Methods: Eight water samples were chosen randomly and collected for physicochemical and microbiological analyses. Isolation of halophilic archaea was carried out by membrane filter technique. Ten strains were identified by polyphasic approach and tested for enzymes production., Results: Water samples of Djelfa's rock salt were slightly acidic to neutral in pH (6.55-7.36) with salinity ranging from 258.68 g/l to 493.91 g/l. Phenotypic, biochemical, taxonomic and phylogenetic characteristics indicated that all strains were classified within the family of Halobacteiaceae . Based on the comparison of DNA sequences encoded 16S rRNA, it was determined that seven strains were affiliated to the genus Haloarcula , two strains were related to the genus Halobacterium and one strain within the genus Haloferax . Production of different enzymes such as protease, amylase, esterase, lipase, lecithinase, gelatinase and cellulase on solid medium indicated that one strain (S2-2) produced amylase, esterase, lecithinase and protease. However, no strains showed cellulolytic or lipolytic activity. Gelatinase was found in all tested strains., Conclusion: This report constitutes the first preliminary study of culturable halophilic archaea recovered from the brines of Djelfa's rock salt with a promising enzymatic potential in various fields of biotechnology., (Copyright © 2022 The Authors. Published by Tehran University of Medical Sciences.)

In this study, we report on the self-assembly of the organic electron donor 2,3,6,7,10,11-hexamethoxytriphenylene (HAT) on graphene grown epitaxially on Ir(111). Using scanning tunneling microscopy and low-energy electron diffraction, we find that a monolayer of HAT assembles in a commensurate close-packed hexagonal network on graphene/Ir(111). X-ray and ultraviolet photoelectron spectroscopy measurements indicate that no charge transfer between the HAT molecules and the graphene/Ir(111) substrate takes place, while the work function decreases slightly. This demonstrates that the HAT/graphene interface is weakly interacting. The fact that the molecules nonetheless form a commensurate network deviates from what is established for adsorption of organic molecules on metallic substrates where commensurate overlayers are mainly observed for strongly interacting systems., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

DNA thermal denaturation was evaluated as a measure of the effect of antitumor drug actinomycin D on the stability of the double helix and also the effect of SDS micelles on actinomycin D - DNA complexes. The results indicated that the melting temperature of DNA was dependent on drug concentration, increasing with actinomycin D concentration. High thermal stabilization (about 10 °C) of the DNA helix after the association with actinomycin D clearly demonstrates the intercalative binding mode. The presence of SDS micelles leads to the release of intercalated actinomcyin D molecules from DNA double helix and their further relocation in surfactant micelles. These results highlighted that the drug release can be controlled in time and by varying the concentration and nature of surfactant.

We report the structural and electronic properties of narrow chevron-like graphene nanoribbons (GNRs), which depending on their length are either mirror or inversion symmetric. Additionally, GNRs of different length can form molecular heterojunctions based on an unusual binding motif., Competing Interests: The authors declare no conflicts of interest., (This journal is © The Royal Society of Chemistry.)

Salt-tolerant enzymes produced by halophilic and halotolerant microorganisms have been proposed to be used in various applications that involve high saline conditions. Considering their biotechnological significance and the current need for more efficient producers of such catalysts, the present study aimed to evaluate the extracellular proteolytic, esterolytic, cellulolytic and xylanolytic activities of some halotolerant strains, and to characterize their functional parameters. A total of 21 bacterial and fungal strains belonging to the genera Bacillus , Virgibacillus , Salinivibrio , Salinicoccus , Psychrobacter , Nocardiopsis , Penicillium , Aspergillus , and Emericellopsis were assayed by quantitative methods. Among them, the members of the Bacillus genus exhibited the highest catalytic activities. The exoenzymes produced by three selected Bacillus strains were active over wide ranges of salinity, temperature and pH. Proteases were active at 20-80 °C, pH 6-10, and 0-1 M NaCl, while esterases showed good catalytic activities at 20-80 °C, pH 7.5-10, and 0-4 M NaCl. Cellulases and xylanases were active at 20-80 °C, pH 5-10, and 0-5 M NaCl. Due to such properties, these hydrolases could be used in a newly proposed application, namely to clean aged consolidants and organic deposits accumulated over time from the surfaces of salt-loaded wall paintings.

One of the current research objectives is the development of new films for the conservation of glass heritage objects. The value of historical glass objects is given by the technology and raw materials used in production as well as their transparency and color. Their colors are correlated with oxide composition rich in transitional metals, which decrease resistance of corrosive agents from the atmosphere. In this paper, SiO 2 -ZnO gels have been designed to protect historical glass objects. The sol-gel method used to obtain gels is a powerful tool for functionalizing different materials. An important functionalization is the antibacterial activity. By applying a gel, the coated material is able to decrease the growth of bacteria. After deposition, some gels must be strengthened by heat treatment. The effect of ZnO content (10 mol% and 20 mol%) on the properties of the studied gels was investigated by Differential scanning calorimetry (DSC), Fourier transform infrared (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), and antibacterial tests. Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, and the halotolerant bacterium, Virgibacillus halodenitrificans , isolated from a salt crystal from Unirea mine, Slănic Prahova, Romania, were used. The gel Gel 2 (SiO 2 -ZnO (20 mol%)) showed the best properties.

In recent studies, porphyrin derivatives have been frequently used as building blocks for the fabrication of metal-organic coordination networks (MOCNs) on metal surfaces under ultrahigh vacuum conditions (UHV). The porphyrin core can host a variety of 3d transition metals, which are usually incorporated in solution. However, the replacement of a pre-existing metal atom in the porphyrin core by a different metallic species has been rarely reported under UHV. Herein, we studied the influence of cyanophenyl and pyridyl functional endgroups in the self-assembly of structurally different porphyrin-based MOCNs by the deposition of Fe atoms on tetracyanophenyl (Co-TCNPP) and tetrapyridyl-functionalized (Zn-TPPyP) porphyrins on Au(111) by means of scanning tunneling microscopy (STM). A comparative analysis of the influence of the cyano and pyridyl endgroups on the formation of different in-plane coordination motifs is performed. Each porphyrin derivative formed two structurally different Fe-coordinated MOCNs stabilized by three- and fourfold in-plane coordination nodes, respectively. Interestingly, the codeposited Fe atoms did not only bind to the functional endgroups but also reacted with the porphyrin core of the Zn-substituted porphyrin (Zn-TPyP), i.e., an atom exchange reaction took place in the porphyrin core where the codeposited Fe atoms replaced the Zn atoms. This was evidenced by the appearance of molecules with an enhanced (centered) STM contrast compared with the appearance of Zn-TPyP, which suggested the formation of a new molecular species, i.e., Fe-TPPyP. Furthermore, the porphyrin core of the Co-substituted porphyrin (Co-TCNPP) displayed an off-centered STM contrast after the deposition of Fe atoms, which was attributed to the binding of the Fe atoms on the top site of the Co-substituted porphyrin core. In summary, the deposition of metal atoms onto organic layers can steer the formation of structurally different MOCNs and may replace pre-existing metal atoms contained in the porphyrin core., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)