31 research outputs found
Ruthenium polypyridyl complexes and their modes of interaction with DNA : is there a correlation between these interactions and the antitumor activity of the compounds?
Various interaction modes between a group of six ruthenium polypyridyl complexes and DNA have been studied using a number of spectroscopic techniques. Five mononuclear species were selected with formula [Ru(tpy) L1L2](2-n)?, and one closely related dinuclear cation of formula [{Ru(apy)(tpy)}2{l-H2N(CH2)6NH2}]4?. The ligand tpy is 2,20:60,200-terpyridine and the ligand L1 is a bidentate ligand, namely, apy (2,20-azobispyridine), 2-phenylazopyridine, or 2-phenylpyridinylmethylene amine. The ligand L2 is a labile monodentate ligand, being Cl-, H2O, or CH3CN. All six species containing a labile L2 were found to be able to coordinate to the DNA model base 9-ethylguanine by 1H NMR and mass spectrometry. The dinuclear cationic species, which has no positions available for coordination to a DNA base, was studied for comparison purposes. The interactions between a selection of four representative complexes and calf-thymus DNA were studied by circular and linear dichroism. To explore a possible relation between DNA-binding ability and toxicity, all compounds were screened for anticancer activity in a variety of cancer cell lines, showing in some cases an activity which is comparable to that of cisplatin. Comparison of the details of the compound structures, their DNA binding, and their toxicity allows the exploration of structureâactivity relationships that might be used to guide optimization of the activity of agents of this class of compounds
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Reference architectures, platforms, and pilots for european smart and healthy livingâanalysis and comparison
Motivated by the aging trend, much effort is being invested into implementing ICT (Information and Communications Technology)-enabled systems to provide a better quality of life and support the independent living of older people. As a result, many systems, often labeled as eHealth or AAL (Ambient/Active Assisted Living), were developed over the years. In creating such systems, which very often serve various needs, different architectures have emerged. This work focuses on analyzing and comparing the work and architectures from seven (six of which are in progress) EU-funded healthcare projects, with a total budget of 126MEUR in which we participate. After establishing the theoretical foundation by defining core concepts, we give a brief background on architectures in eHealth and AAL. We elaborate on the chosen analysis method based on three established healthcare and AAL taxonomies we identified by performing a literature survey and the selected Reference Architecture Model (RAM). Since there is no standard way of describing architectures in the eHealth and AAL domain, we conducted the online survey during August and September 2020 and identified CREATE-IoT 3D RAM as the most appropriate option. We present a classification of selected projects based on established taxonomies and map projectsâ architectures to CREATE-IoT 3D RAM, which we also propose as standard RAM for future digital healthcare and AAL projects. During our analysis, we identify the most common types of assistance: communication support, reminders, monitoring, and guidance to address health and communication issues. We conclude that proper ecosystems are critical for lowering entry barriers and facilitating sustainable solutions for smart and healthy living
Orientational Effects and Random Mixing in 1âAlkanol + Nitrile Mixtures
1-Alkanol + alkanenitrile or + benzonitrile systems have been investigated by means of the molar excess
functionsenthalpies (Hm E ), isobaric heat capacities (Cp,m
E ), volumes (Vm E ), and entropiesand using the Flory model and the
concentrationâconcentration structure factor (SCC(0)) formalism. From the analysis of the experimental data available in the
literature, it is concluded that interactions are mainly of dipolar type. In addition, large Hm E values contrast with rather low Vm E
values, indicating the existence of strong structural effects. Hm E measurements have been used to evaluate the enthalpy of the
hydroxylânitrile interactions (ÎHOHâCN). They are stronger in methanol systems and become weaker when the alcohol size
increases. In solutions with a given short chain 1-alkanol (up to 1-butanol), the replacement of ethanenitrile by butanenitrile
weakens the mentioned interactions. Application of the Flory model shows that orientational effects exist in methanol or 1-
nonanol, or 1-decanol + ethanenitrile mixtures. In the former solution, this is due to the existence of interactions between unlike
molecules. For mixtures including 1-nonanol or 1-decanol, the systems at 298.15 K are close to their UCST (upper critical
solution temperature), and interactions between like molecules are dominant. Orientational effects also are encountered in
methanol or ethanol + butanenitrile mixtures because self-association of the alcohol plays a more important role. Aromaticity
effect seems to enhance orientational effects. For the remainder of the systems under consideration, the random mixing
hypothesis is attained to a rather large extent. Results from the application of the SCC(0) formalism show that homocoordination
is the dominant trend in the investigated solutions, and are consistent with those obtained from the Flory model
Cu L2,3 X-ray absorption spectroscopy and the electronic structure of minerals: Spectral variations in non-stoichiometric bornites, Cu5FeS4.
Cu L-3 X-ray absorption spectroscopy and the electronic structure of minerals: Spectral variations in non-stoichiometric bornites, Cu5FeS4
Design and Evaluation of Personalized Services to Foster Active Aging: The Experience of Technology Pre-Validation in Italian Pilots
Assistive devices could promote independent living and support the active and healthy aging of an older population; however, several factors can badly influence the long-term use of new technologies. In this context, this paper presents a two-step methodology called âpre-validationâ that aims to identify the factors that can bias the use of new services, thus minimizing the risk of an unsuccessful longer trial. The proposed pre-validation methodology is composed of two main phases that aim to assess the usability and the reliability of the technology assessed in a laboratory environment and the usability, acceptability, user experience, and reliability of the technology in real environments. The tested services include the socialization scenario, in which older adults are better connected to the community via technological solutions (i.e., socialization applications), and the monitoring scenario, which allows for the introduction of timely interventions (technologies involved include environmental monitoring sensors, a telepresence robot, wearable sensors, and a personalized dashboard). The obtained results underline an acceptable usability level (average System Usability Scale score > 65) for the tested technologies (i.e., socialization applications and a telepresence robot). Phase Two also underlines the good acceptability, user experience, and usability of the tested services. The statistical analysis underlines a correlation between the stress related to the use of technology, digital skills, and intention of use, among other factors. Qualitative feedback also remarks on a correlation between older adults with low digital skills and an anxiety about using technology. Positive correlation indexes were highlighted between the trust and usability scores. Eventually, future long-term trials with assistive technology should rely on motivated caregivers, be founded on a strong recruitment process, and should reassure older adultsâespecially the ones with low digital literacyâabout the use of technology by proposing personalized training and mentoring, if necessary, to increase the trust