Luther on Christ and the Old Testament

Careful reading of this article will contribute to getting the hermeneutical debate in our Synod beyond the present impasse that has been created by a non-Lutheran posing of the alternatives by so many who are involved in the debate

Photophysical and structural properties of the fluorescent nucleobase analogues of the tricyclic cytosine (tC) family

Fundamental insight into the unique fluorescence and nucleobase-mimicking properties of the fluorescent nucleobase analogues of the tC family is not only vital in explaining the behaviour of these probes in nucleic acid environments, but will also be profitable in the development of new and improved fluorescent base analogues. Here, temperature-dependent fluorescence quantum yield measurements are used to successfully separate and quantify the temperature-dependent and temperature-independent non-radiative excited-state decay processes of the three nucleobase analogues tC, tC(O) and tC(nitro); all of which are derivatives of a phenothiazine or phenoxazine tricyclic framework. These results strongly suggest that the non-radiative decay process dominating the fast deactivation of tCnitro is an internal conversion of a different origin than the decay pathways of tC and tC(O). tCnitro is reported to be fluorescent only in less dipolar solvents at room temperature, which is explained by an increase in excited-state dipole moment along the main non-radiative decay pathway, a suggestion that applies in the photophysical discussion of large polycyclic nitroaromatics in general. New insight into the ground and excited-state potential energy surfaces of the isolated tC bases is obtained by means of high level DFT and TDDFT calculations. The S-0 potential energy surfaces of tC and tCnitro possess two global minima corresponding to geometries folded along the middle sulfur-nitrogen axis separated by an energy barrier of 0.05 eV as calculated at the B3LYP/6-311 + G(2d, p) level. The ground-state potential energy surface of tC(O) is also predicted to be shallow along the bending coordinate but with an equilibrium geometry corresponding to the planar conformation of the tricyclic framework, which may explain some of the dissimilar properties of tC and tC(O) in various confined (biological) environments. The S-1 equilibrium geometries of all three base analogues are predicted to be planar. These results are discussed in the context of the tC bases positioned in double-stranded DNA scenarios

Characterization of Nucleobase Analogue FRET Acceptor tC(nitro)

The fluorescent nucleobase analogues of the tricyclic cytosine (tC) family, tC and tC(O), possess high fluorescence quantum yields and single fluorescence lifetimes, even after incorporation into double-stranded DNA, which make these base analogues particularly useful as fluorescence resonance energy transfer (FRET) probes. Recently, we reported the first all-nucleobase FRET pair consisting of tC(O) as the donor and the novel tC(nitro) as the acceptor. The rigid and well-defined position of this FRET pair inside the DNA double helix, and consequently excellent control of the orientation factor in the FRET efficiency, are very promising features for future studies of nucleic acid structures. Here, we provide the necessary spectroscopic and photophysical characterization Of tC(nitro) needed in order to utilize this probe as a FRET acceptor in nucleic acids. The lowest energy absorption band from 375 to 525 nm is shown to be the result of a single in-plane polarized electronic transition oriented similar to 27 degrees from the molecular long axis, This band overlaps the emission bands of both tC and tC(O), and the Forster characteristics of these donor-acceptor pairs are calculated for double-stranded DNA scenarios. In addition, the UV-vis absorption of tC(nitro) is monitored in a broad pH range and the neutral form is found to be totally predominant under physiological conditions with a pK(a) of 11.1. The structure and electronic spectrum Of tC(nitro) is further characterized by density functional theory calculations

Development of bright fluorescent quadracyclic adenine analogues: TDDFT-calculation supported rational design

Fluorescent base analogues (FBAs) comprise a family of increasingly important molecules for the investigation of nucleic acid structure and dynamics. We recently reported the quantum chemical calculation supported development of four microenvironment sensitive analogues of the quadracyclic adenine (qA) scaffold, the qANs, with highly promising absorptive and fluorescence properties that were very well predicted by TDDFT calculations. Herein, we report on the efficient synthesis, experimental and theoretical characterization of nine novel quadracyclic adenine derivatives. The brightest derivative, 2-CNqA, displays a 13-fold increased brightness (epsilon Phi(F) = 4500) compared with the parent compound qA and has the additional benefit of being a virtually microenvironment-insensitive fluorophore, making it a suitable candidate for nucleic acid incorporation and use in quantitative FRET and anisotropy experiments. TDDFT calculations, conducted on the nine novel qAs a posteriori, successfully describe the relative fluorescence quantum yield and brightness of all qA derivatives. This observation suggests that the TDDFT-based rational design strategy may be employed for the development of bright fluorophores built up from a common scaffold to reduce the otherwise costly and time-consuming screening process usually required to obtain useful and bright FBAs

Fluorescent RNA cytosine analogue - an internal probe for detailed structure and dynamics investigations

The bright fluorescent cytosine analogue tCO stands out among fluorescent bases due to its virtually unquenched fluorescence emission in duplex DNA. However, like most reported base analogues, it has not been thoroughly characterized in RNA. We here report on the first synthesis and RNA-incorporation of tCO, and characterize its base-mimicking and fluorescence properties in RNA. As in DNA, we find a high quantum yield inside RNA duplexes (<?F> = 0.22) that is virtually unaffected by the neighbouring bases (?F = 0.20-0.25), resulting in an average brightness of 1900 M-1 cm-1. The average fluorescence lifetime in RNA duplexes is 4.3 ns and generally two lifetimes are required to fit the exponential decays. Fluorescence properties in ssRNA are defined by a small increase in average quantum yield (<?F > = 0.24) compared to dsRNA, with a broader distribution (?F = 0.17-0.34) and slightly shorter average lifetimes. Using circular dichroism, we find that the tCO-modified RNA duplexes form regular A-form helices and in UV-melting experiments the stability of the duplexes is only slightly higher than that of the corresponding natural RNA (<?T m> = + 2.3 °C). These properties make tCO a highly interesting fluorescent RNA base analogue for detailed FRET-based structural measurements, as a bright internal label in microscopy, and for fluorescence anisotropy measurements of RNA dynamics

Visuo-spatial cognition in Williams syndrome: Reviewing and accounting for the strengths and weaknesses in performance

Individuals with Williams syndrome typically show relatively poor visuo-spatial abilities in comparison to stronger verbal skills. However, individuals' level of performance is not consistent across all visuo-spatial tasks. The studies assessing visuo-spatial functioning in Williams syndrome are critically reviewed, in order to provide a clear pattern of the relative difficulty of these tasks. This prompts a possible explanation of the variability in performance seen which focuses on the processing demands of some of these tasks. Individuals with Williams syndrome show an atypical processing style on tests of construction, which does not affect tests of perception

Inherited variants in regulatory T cell genes and outcome of ovarian cancer.

Although ovarian cancer is the most lethal of gynecologic malignancies, wide variation in outcome following conventional therapy continues to exist. The presence of tumor-infiltrating regulatory T cells (Tregs) has a role in outcome of this disease, and a growing body of data supports the existence of inherited prognostic factors. However, the role of inherited variants in genes encoding Treg-related immune molecules has not been fully explored. We analyzed expression quantitative trait loci (eQTL) and sequence-based tagging single nucleotide polymorphisms (tagSNPs) for 54 genes associated with Tregs in 3,662 invasive ovarian cancer cases. With adjustment for known prognostic factors, suggestive results were observed among rarer histological subtypes; poorer survival was associated with minor alleles at SNPs in RGS1 (clear cell, rs10921202, p = 2.7×10(-5)), LRRC32 and TNFRSF18/TNFRSF4 (mucinous, rs3781699, p = 4.5×10(-4), and rs3753348, p = 9.0×10(-4), respectively), and CD80 (endometrioid, rs13071247, p = 8.0×10(-4)). Fo0r the latter, correlative data support a CD80 rs13071247 genotype association with CD80 tumor RNA expression (p = 0.006). An additional eQTL SNP in CD80 was associated with shorter survival (rs7804190, p = 8.1×10(-4)) among all cases combined. As the products of these genes are known to affect induction, trafficking, or immunosuppressive function of Tregs, these results suggest the need for follow-up phenotypic studies

DNA origami-based single-molecule forcespectroscopy elucidates RNA Polymerase IIIpre-initiation complex stability

The TATA-binding protein (TBP) and a transcription factor (TF) IIB-like factor are important constituents of all eukaryotic initiation complexes. The reason for the emergence and strict requirement of the additional initiation factor Bdp1 in the RNA polymerase (RNAP) III system, however, remained elusive. A poorly studied aspect in this context is the effect of DNA strain arising from DNA compaction and transcriptional activity on initiation complex formation. We made use of a DNA origami-based force clamp to follow the assembly of human initiation complexes in the RNAP II and RNAP III systems at the single-molecule level under piconewton forces. We demonstrate that TBP-DNA complexes are force-sensitive and TFIIB is sufficient to stabilise TBP on a strained promoter. In contrast, Bdp1 is the pivotal component that ensures stable anchoring of initiation factors, and thus the polymerase itself, in the RNAP III system. Thereby, we offer an explanation for the crucial role of Bdp1 for the high transcriptional output of RNAP III