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New cyclam-based complexes of formulae [{H2(4-CF3PhCH2)2Cyclam}FeCl2]Cl and [{H2(4-CF3PhCH2)2Cyclam}Cu](CH3COO)2·2H2O were synthesized, in very high yields, by the reaction of H2(4-CF3PhCH2)2Cyclam with the corresponding metal salts in methanol. [{H2(4-CF3PhCH2)2Cyclam}FeCl2]Cl was also prepared, quantitatively, in the solid state by mechanochemistry. The Mössbauer spectra of [{H2(4-CF3PhCH2)2Cyclam}FeCl2]Cl show that the high-spin cis complex is the major product of both reactions. The EPR data of [{H2(4-CF3PhCH2)2Cyclam}Cu](CH3COO)2·2H2O are consistent with two distinct Cu2+ species, whose solid state molecular structures were determined by single crystal X-ray diffraction and correspond to complexes displaying octahedral and square–pyramidal geometries. The screening of the antifungal activity of both metal complexes revealed the higher activity of [{H2(4-CF3PhCH2)2Cyclam}FeCl2]Cl to inhibit the growth of unicellular and multicellular fungal species with described pathogenic potential. [ABSTRACT FROM AUTHOR]

Rejection and colonization by microbes are two problematic issues that often require the surgical removal of medical implants with increased risks for patients. In this work it is shown that functionalization of Zn surfaces with ZnO-nanostructured 'Anastacia' flowers (NAF) resulted in improved biomaterials that can potentially overcome these important drawbacks, which can further boost the use of Zn in biomedical implants. The in vitro degradation of NAF-coated Zn under simulated physiological conditions resulted in the formation of a biomimetic corrosion layer rich in a hydroxyapatite analogue that, being an important bone component, may potentially decrease implant rejection. Colonization of the NAF-coated Zn surface by Candida parapsilosis and Candida albicans, two of the more relevant microbial species colonizing medical devices, was significantly reduced on the NAF-coated Zn surface. The mechanism by which this colonization inhibition occurred was distinct since for C. parapsilosis cells this was attributed to reduced cell viability, while for C. albicans the reduced colonization was related to impaired biofilm formation. This ZnO-derived coating is an expeditious strategy to improve the resilience of Zn-based resorbable biomaterials towards Candida spp. colonization, paving the way for the design of bioactive ZnO-derived coatings with potential for clinical applications on bone. [ABSTRACT FROM AUTHOR]

Advanced impedance spectroscopy analysis based on the transmission line model (TLM) is explored as a novel QCM acoustic biosensing platform for the detection of the single point mutation effect on the binding of the transcription factors (TFs) to immobilized DNA oligoduplexes and the characterization of the protein–DNA mechanical properties. [ABSTRACT FROM AUTHOR]

A novel quartz crystal microbalance (QCM) analytical method is developed based on the transmission line model (TLM) algorithm to analyze the binding of transcription factors (TFs) to immobilized DNA oligoduplexes. The method is used to characterize the mechanical properties of biological films through the estimation of the film dynamic shear moduli, GSTACKABOVE′/ABOVEBELOWfilm/BELOW/STACK and GSTACKABOVE′′/ABOVEBELOWfilm/BELOW/STACK, and the film thickness. Using the Saccharomyces cerevisiae transcription factor Haa1 (Haa1DBD) as a biological model two sensors were prepared by immobilizing DNA oligoduplexes, one containing the Haa1 recognition element (HREwt) and another with a random sequence (HREneg) used as a negative control. The immobilization of DNA oligoduplexes was followed in real time and we show that DNA strands initially adsorb with low or non-tilting, laying flat close to the surface, which then lift-off the surface leading to final film tilting angles of 62.9° and 46.7° for HREwt and HREneg, respectively. Furthermore we show that the binding of Haa1DBD to HREwt leads to a more ordered and compact film, and forces a 31.7° bending of the immobilized HREwt oligoduplex. This work demonstrates the suitability of the QCM to monitor the specific binding of TFs to immobilized DNA sequences and provides an analytical methodology to study protein–DNA biophysics and kinetics. [ABSTRACT FROM AUTHOR]