Graph comparison by log-odds score matrices with application to protein topology analysis

A TOPS diagram is a simplified description of the topology of a protein using a graph where nodes are alpha-helices and beta-strands, and edges correspond to chirality relations and parallel or antiparallel bonds between strands. We present a matching algorithm between two TOPS diagrams where the likelihood of a match is measured according to previously known matches between complete 3D structures. This totally new 3D training is recorded on transition matrices that count the likelihood that a given TOPS feature, or combination thereof, is replaced by another feature on homologs. The new algorithm outperforms existing ones on a benchmark database. Some biologically significant examples are discussed as well. The method can be used whenever frequencies of edge relationship matches are known, as it is the case for several biopolymer structures.

Epicardial adipose tissue is an independent predictor of coronary atherosclerotic burden

INTRODUCTION

Epicardial adipose tissue (EAT) may play an active role in the development of coronary artery disease (CAD). The aim of this work was to study the relations between EAT, abdominal visceral fat (AVF), and coronary atherosclerotic burden as assessed by multislice computed tomography (MSCT).

POPULATION AND METHODS

Two hundred fifteen patients without known CAD referred to 64-SCT during a 6-months period were included. All patients underwent a standardized protocol including quantification of AVF, EAT, coronary artery calcification (CAC), and coronary angiography by MSCT.

RESULTS

Two hundred fifteen patients, with mean age of 58 ± 11 years, in which 61% were males, with mean body mass index (BMI) of 28 ± 4 kg/m(2) were included. EAT volume was directly associated with male sex, age, BMI, abdominal circumference, AVF, number of coronary segments with atherosclerotic plaques (p<0.01 for all), number of segments with significant stenoses, and presence of metabolic syndrome components (p<0.05). CAC increased by 14.7% per additional 10 ml of EAT volume. Adjusting for age, gender, and AVF changed this increase to 7.5%. After adjusting for all considered confounders, there was still an independent association, with a CAC increase of 3.7% per additional 10 ml of EAT. A significant interaction was found between EAT volume and gender and between EAT volume and obesity: an increase of EAT was associated with an increase of additional 8% of CAC in men, and additional increase of 5% in non-obese individuals (p<0.001 for both).

CONCLUSION

EAT volume positively relates to coronary atherosclerotic burden, as assessed by CAC; this correlation was shown to be independent of AVF.

Functional cationic nanomagnet-porphyrin hybrids for the photoinactivation of microorganisms

Cationic nanomagnet-porphyrin hybrids were synthesized and their photodynamic therapy capabilities were investigated against the Gram (-) Escherichia coli bacteria, the Gram (+) Enterococcus faecalis bacteria and T4-like phage. The synthesis, structural characterization, photophysical properties, and antimicrobial activity of these new materials are discussed. The results show that these new multicharged nanomagnet-porphyrin hybrids are very stable in water and highly effective in the photoinactivation of bacteria and phages. Their remarkable antimicrobial activity, associated with their easy recovery, just by applying a magnetic field, makes these materials novel photosensitizers for water or wastewater disinfection.

Luminescent multifunctional lanthanides-based metal-organic frameworks

Metal-organic frameworks based on trivalent lanthanides (LnMOFs) are a very promising class of materials for addressing the challenges in engineering of luminescent centres. Lanthanide-bearing phosphors find numerous applications in lighting, optical communications, photonics and biomedical devices. In this critical review we discuss the potential of LnMOFs as multifunctional systems, which combine light emission with properties such as microporosity, magnetism, chirality, molecule and ion sensing, catalysis and activity as multimodal imaging contrast agents. We argue that these materials present a unique chance of observing synergy between several of these properties, such as the coupling between photoluminescence and magnetism. Moreover, an integrated approach towards the design of efficient, stable, cheap, environmentally-friendly and multifunctional luminescent LnMOFs is still missing. Although research into LnMOFs is at its early stage and much basic knowledge is still needed, the field is ripe for new ideas, which will enable sensor devices and photonic prototypes to become a commercial reality (81 references).

Trimethyl 2,2',2''-[1,3,5-triazine-2,4,6-tri-yltris-(aza-nedi-yl)]triacetate

The title compound, C₁₂H₁₈N₆O₆, was synthesized via nucleophilic substitution by reacting 2,4,6-trichloro-1,3,5-triazine with glycine methyl ester hydro­chloride in reflux (dried toluene) under anhydrous atmosphere. Individual mol­ecules self-assemble via strong N—H⋯O hydrogen bonds into supra­molecular double tapes running parallel to the [010] crystallographic direction. The close packing of supra­molecular tapes is mediated by geometrical reasons in tandem with a number of weaker N—H⋯O and C—H⋯N hydrogen-bonding inter­actions.

trans-Bis(4,7-diphenyl-1,10-phenanthroline-κN,N')bis-(nitrato-κO,O')zinc(II)

The title compound, [Zn(NO(3))(2)(C(24)H(16)N(2))(2)], is a twofold axially symmetric coordination compound. Given that the Zn-O interactions [2.4926 (15) and 2.6673 (15) Å] can be considered as weakly bonding and the nitrate ions share the same C(2) axis of the Zn(dpp)(2) fragment (dpp is 4,7-diphenyl-1,10-phenanthroline), these anions belong to the coordination sphere of Zn(2+), leading to a complex with an overall coordination number of 8 for the metal ion.

3D-2D-0D stepwise deconstruction of a water framework templated by a nanoporous organic-inorganic hybrid host

The supramolecular salt [H(2)pip](3)[Ge(hedp)(2)].14H(2)O (1) [H(2)pip(2+)=piperazine cation C(4)H(12)N(2)(2+); hedp(5-)=deprotonated form of etidronic acid, C(2)H(3)P(2)O(7)(5-)) is reported. This consists of an organic-inorganic hybrid hydrogen-bonded nanoporous framework, the internal surface of which acts as a template for the three-dimensional (3D) clustering of water molecules. The structure and molecular dynamics of this material are characterised by single-crystal X-ray diffraction, thermogravimetric analysis, Raman (H/D isotopic substitution) spectroscopy, and (2)H solid-state (wide-line and MAS) NMR spectroscopy. Material 1 is shown to be unusual because 1) few nanoporous materials exhibit a well-organised 3D framework of water molecules, 2) it provides a unique opportunity to follow experimentally and to rationalise the deconstruction of a 3D water framework and 3) despite the fact that the hybrid framework is a supramolecular salt, the structure does not collapse after dehydration and the final material is crystalline.

Fine tuning of the relaxometry of γ-Fe2O3@SiO2 nanoparticles by tweaking the silica coating thickness

We report the fine-tuning of the relaxometry of gamma-Fe2O3@SiO2 core-shell nanoparticles by adjusting the thickness of the coated silica layer. It is clear that the coating thickness of Fe2O3@SiO2 nanoparticles has a significant impact on the r(1) (at low B0 fields), r(2), and r(2)* relaxivities of their aqueous suspensions. These studies clearly indicate that the silica layer is heterogeneous and has regions that are porous to water and others-that are not. It is also shown, that the viability and the mitochondrial dehydrogenase expression of the microglial cells do not appear to be sensitive to the vesicular load with these core-shell nanoparticles. The adequate silica-shell thickness can therefore be tuned to allow for both a sufficiently high response as contrast agent, and-adequate grafting of targeted biomolecules.

(R)-(1-Ammonio-eth-yl)phospho-nate

The title compound, C₂H₈NO₃P, crystallizes in its zwitterionic form H₃N⁺CH(CH₃)PO(O⁻)(OH). In the crystal, the molecules are linked by N—H⋯O and O—H⋯O hydrogen bonds.

In vivo anti-inflammatory effect and toxicological screening of Maytenus heterophylla and Maytenus senegalensis extracts

Maytenus heterophylla (Eckl & Zeyh.) Robson and Maytenus senegalensis (Lam). Exell are two African medicinal plants used to treat painful and inflammatory diseases. We evaluated the in vivo (per os) anti-inflammatory activity of M. heterophylla leaf, stem and root extracts and of M. senegalensis leaf and stem extracts. Additionally, we assessed their in vivo acute and sub-acute toxicities. Anti-inflammatory activities of ethanol extracts were determined in Wistar albino rats, by the carrageenan-induced paw oedema method. Acute and sub-acute toxicity screening of the extracts was evaluated in adult male CD-6 mice. Leaf extracts of M. heterophylla and M. senegalensis exhibited significant anti-inflammatory activity (120 mg/kg, per os), reducing oedema by 51% and 35%, respectively. While M. heterophylla extracts at 1200 mg/kg have shown to be non-toxic, M. senegalensis extracts indicated some toxicity. Our results show a significant anti-inflammatory effect of both M. heterophylla and M. senegalensis leaf extracts in a local model of acute inflammation and suggest the absence of acute and sub-acute toxicity signs of the M. heterophylla leaf extract (but not of M. senegalensis). Ongoing studies will surely shed some light into the mechanism of action of this active extract and establish its chemical fingerprint.

Diaqua-bis(ethyl-enediamine-κN,N')copper(II) bis-(4-phenyl-benzoate) 2.66-hydrate

In the title complex, [Cu(C(2)H(8)N(2))(2)(H(2)O)(2)](C(13)H(9)O(2))(2)·2.66H(2)O, the Cu(II) centre (located at an inversion centre) is coordinated by two bidentate ethyl-enediamine (en) ligands and two water O atoms in a typical Jahn-Teller distorted octahedral geometry. The amino groups and the water mol-ecules are disordered over two distinct crystallographic positions with occupancies of 1/3 and 2/3. In the crystal, the cations and anions are disposed in alternating layers. One of the water mol-ecules of crystallization is disordered and the other has a fractional occupation. In the 2/3 occupancy component, water mol-ecules are organized into a chain composed of hexa-meric units inter-connected by carboxyl-ate bridges.