Quantitative analysis of the effect of derivatisation of [Ru(BPY) phen] with a quinoline moiety on the interaction with DNA

The bifunctional Ru(II) complex [Ru(BPY)2POQ-Nmet]2+ (1), in which the metallic unit is tethered by an aliphatic chain to an organic DNA binder, was designed in order to increase the affinity toward nucleic acids. The interaction of 1 with DNA was characterised from luminescence and absorption data and compared with the binding of its monofunctional metallic and organic analogues, [Ru(BPY)2(ac)phen]2+ (2) and Nmet-quinoline (3). The bifunctional complex has a binding affinity one order of magnitude higher than that of each of its separated moieties. Absorption changes induced upon addition of DNA at different pH indicate protonation of the organic sub-unit upon interaction with DNA under neutral conditions. The combination of the luminescence data under steady-state and time-resolved conditions shows that the attachment of the organic unit in 1 induces modifications of the association modes of the metallic unit, owing to the presence of the aliphatic chain which probably hinders the metallic moiety binding. The salt dependence of the binding constants was analysed in order to compare the thermodynamic parameters describing the association with DNA for each complex. This study demonstrates the interest of the derivatisation of a Ru(II) complex with an organic moiety (ia the bifunctional ligand POQ-Nmet) for the development of high affinity DNA probes or photoreactive agents.

Analysis of the peripheral T-cell compartment in the MHC class II deficiency syndrome.

To analyse the impact of lack of MHC class II expression on the composition of the peripheral T-cell compartment in man, the expression characteristics of several membrane antigens were examined on peripheral blood lymphocytes (PBL) and cultured T cells derived from an MHC-class-II-deficient patient. No MHC class II expression could be detected on either PBL or activated T cells. Moreover, the expression of MHC class I was reduced both on PBL and in vitro activated T cells compared to the healthy control. However, the reduced expression of CD26 observed on the PBL of the patient was restored after in vitro expansion. Despite the presumably class-II-deficient thymic environment, a distinct but reduced single CD4+ T-cell population was observed in the PBL of the patient. After in vitro expansion, the percentage of CD4+ cells dropped even further, most likely due to a proliferative disadvantage, compared to the single CD8+ T-cell population. However, proliferation analysis showed that T-cell activation via the TcR/CD3 pathway is not affected by the MHC class II deficiency.

Discoplana malagasensis sp. nov. a New Turbellarian (Platyhelminthes: Polycladida: Leptoplanidae) symbiotic in an ophiuroid (Echinodermata), with a cladistic analysis of the Discoplana/Euplana species

A new species of polyclad flatworm from Papua New Guinea is described. It is found symbiotic in the ophiuroid Ophiothrix purpurea von Martens, 1867 (Echinodermata: Ophiuroidea). Apparently it belongs to the taxon Discoplana Bock, 1913 and can be distinguished from the six previously described Discoplana species by its very short ejaculatory duct and a penial papilla covered with a penial sheath, but without any true sclerotised structures such as a stylet or spines. The cladistic analysis of the Discoplana/Euplana species, based on morphological features and including two outgroups, reveals that all species of Discoplana, except D. pacificola, form a monophyletic taxon, that is not a synonym of Euplana Girard, 1893. Therefore the name Discoplana is conserved and the new species will be described as Discoplana malagasensis sp. nov. A key for the Discoplana/Euplana group is provided. In this key the biogeographical distribution and possible synonyms are given.

Expression, purification and X-ray crystallographic analysis of the Helicobacter pylori blood group antigen-binding adhesin BabA

Helicobacter pylori is a human pathogen that colonizes about 50% of the world's population, causing chronic gastritis, duodenal ulcers and even gastric cancer. A steady emergence of multiple antibiotic resistant strains poses an important public health threat and there is an urgent requirement for alternative therapeutics. The blood group antigen-binding adhesin BabA mediates the intimate attachment to the host mucosa and forms a major candidate for novel vaccine and drug development. Here, the recombinant expression and crystallization of a soluble BabA truncation (BabA^25-460) corresponding to the predicted extracellular adhesin domain of the protein are reported. X-ray diffraction data for nanobody-stabilized BabA^25-460 were collected to 2.25Å resolution from a crystal that belonged to space group P21, with unit-cell parameters a = 50.96, b = 131.41, c = 123.40Å, α = 90.0, β = 94.8, γ = 90.0°, and which was predicted to contain two BabA^25-460-nanobody complexes per asymmetric unit.

Analysis of the utility of QuantiFERON-TB gold in tube and measurement of IFNgamma release by peripheral mononuclear cells in response to different mycobacterium antigen in the work-up of patients with uveitis.

Evaluation Studies

First High-Resolution Analysis of the Absorption Spectrum of Propane in the 6.7-7.5 μm Spectral Region

info:eu-repo/semantics/published

Rotational analysis of the v6 band in furan (C4H4O)

SCOPUS: no.j

New high-resolution analysis of the ν7 and ν9 fundamental bands of trans-formic acid by IR Fourier transform and millimeterwave spectroscopies

info:eu-repo/semantics/published