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Primary demyelinating disorders of the central nervous system (CNS) include multiple sclerosis and the orphan conditions neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein IgG-associated disease (MOGAD). Curative technologies under development aim to selectively block autoimmune reactions against specific autoantigens while preserving the responsiveness of the immune system to other antigens. Our analysis focused on target patient selection for such developments, carefully considering the relevant clinical, regulatory, and market-related aspects. We found that the selection of patients with orphan conditions as target populations offers several advantages. Treatments for orphan conditions are associated with limited production capacity, qualify for regulatory incentives, and may require significantly shorter and lower-scale clinical programs. Furthermore, they may meet a higher acceptable cost-effectiveness threshold in order to compensate for the low numbers of patients to be treated. Finally, curative technologies targeting orphan indications could enter less competitive markets with lower risk of generic price erosion and would benefit from additional market protection measures available only for orphan products. These advantages position orphan conditions and subgroups as the most attractive target indications among primary demyelinating disorders of the CNS. The authors believe that after successful proof-of-principle demonstrations in orphan conditions, broader autoimmune patient populations may also benefit from the success of these pioneering developments. [ABSTRACT FROM AUTHOR]

Pertuzumab (Perjeta®), a humanized antibody binding to the dimerization arm of HER2 (Human epidermal growth factor receptor-2), has failed as a monotherapy agent in HER2 overexpressing malignancies. Since the molecular interaction of HER2 with ligand-bound EGFR (epidermal growth factor receptor) has been implied in mitogenic signaling and malignant proliferation, we hypothesized that this interaction, rather than HER2 expression and oligomerization alone, could be a potential molecular target and predictor of the efficacy of pertuzumab treatment. Therefore, we investigated static and dynamic interactions between HER2 and EGFR molecules upon EGF stimulus in the presence and absence of pertuzumab in HER2+ EGFR+ SK-BR-3 breast tumor cells using Förster resonance energy transfer (FRET) microscopy and fluorescence correlation and cross-correlation spectroscopy (FCS/FCCS). The consequential activation of signaling and changes in cell proliferation were measured by Western blotting and MTT assay. The autocorrelation functions of HER2 diffusion were best fitted by a three-component model corrected for triplet formation, and among these components the slowly diffusing membrane component revealed aggregation induced by EGFR ligand binding, as evidenced by photon-counting histograms and co-diffusing fractions. This aggregation has efficiently been prevented by pertuzumab treatment, which also inhibited the post-stimulus interaction of EGFR and HER2, as monitored by changes in FRET efficiency. Overall, the data demonstrated that pertuzumab, by hindering post-stimulus interaction between EGFR and HER2, inhibits EGFR-evoked HER2 aggregation and phosphorylation and leads to a dose-dependent decrease in cell proliferation, particularly when higher amounts of EGF are present. Consequently, we propose that EGFR expression on HER2-positive tumors could be taken into consideration as a potential biomarker when predicting the outcome of pertuzumab treatment. [ABSTRACT FROM AUTHOR]

Our recently developed conventional, explicitly correlated, and local natural orbital (LNO) based coupled cluster with single, double, and perturbative triple excitations [CCSD(T)] methods are utilised to closely approach the basis set limit of interaction energies between medium-sized molecular complexes. The study is partly motivated by our previous finding that state-of-the-art diffusion Monte Carlo and CCSD(T) interaction energies are not in complete agreement even for some of the dimers in the popular S66 compilation [Al-Hamdani and Nagy et al. Nat. Commun. (2021) 12:3927]. We improve upon the previous S66 CCSD(T) reference by using up to the quadruple-ζ (QZ) level CCSD(T) contributions, utilising our recent (T+) approach and suggesting a more robust explicitly correlated CCSD reference. Our efficient LNO-CCSD(T) method allowed us to also compute tightly converged, quintuple-ζ level interaction energies for the S66 set. Moreover, the new CCSD(T)/QZ references enabled the so far most rigorous benchmark of the LNO and other popular local correlation approaches on the S66 set. The accuracy of local approximations was found in the few 10 to few 100 cal/mol interaction energy error range, assuming sufficiently tight settings, such as the Tight and the Normal settings of LNO-CCSD(T) threshold combinations, respectively. [ABSTRACT FROM AUTHOR]

In recent years, interest in effective digital learning materials has grown significantly in almost all disciplines, fuelled by the rapid expansion of distance learning in the wake of the worldwide coronavirus pandemic. In our study, we would like to present a new and hopefully promising technology, through the development of an IT e-learning material, which offers an easy-to-use 3D virtual environment for the content to be displayed. This project is based on the use of the Maxwhere system for educational purposes. The MaxWhere environment is a 3D presentation tool developed a few years ago that can be used as an excellent tool for the development and presentation of e-learning materials in both teaching and learning environments. In the development of the curriculum, special attention was dedicated to the content composition from a network-theoretic point of view, focusing on the relationships between the elementary units as hubs and the integration of each hub into the curriculum system. In addition to this, the data content of the resulting curriculum was also analysed from a scale-free perspective. It is assumed that the structure of the curriculum can theoretically be viewed as a network of relevant cognitive units (e.g. chapters, subchapters, pictorial illustrations, etc.) and that the curriculum is likely to be more effective if the interconnection of the individual information units follows the scale-free pattern that has been identified in many networks. It is thus safe to assume that when new knowledge is integrated (i.e. when the material is being learned), the pattern of connections established by the participants in their own cognitive knowledge systems will be similar. Consequently, the brain pattern of memorized information inherits many of the good properties of scale-free networks (e.g. robustness). [ABSTRACT FROM AUTHOR]

Consumer trust and organic food product credibility play a crucial role in understanding consumer behavior. The aim of this review is to identify extrinsic factors which influence consumers' perceived trust in organic food. The research was conducted based on the PRISMA guidelines. During our search, 429 articles were found, from which 55 studies were selected for further analysis. To assess the connection between the selected articles, a bibliometric analysis was done with VOSViewer and CitNetExplorer software. The following factors were identified as influencing the credibility of organic food: labeling, certification, place of purchase, country of origin, brand, price, communication, product category, packaging. From these, labeling, certification, and country of origin are well-researched factors in relation to credibility. The significance of the other discovered factors is supported; nonetheless, further research is needed to evaluate their effect on consumer trust. [ABSTRACT FROM AUTHOR]

In this study, the electrochemical mechanisms of struvite formation were investigated by studying the behavior of Mg‐based and (poly)crystalline‐Pt electrodes in the presence of ammonium dihydrogen phosphate, disodium phosphate, and ammonium chloride solutions. It was found that a precipitate was formed on the Mg‐based electrodes, while the poly‐Pt electrode showed typical voltammetric features in aqueous electrolytes. The structure, morphology, and composition of the electrochemically obtained precipitates collected from the surface of the Mg‐based electrodes were analyzed by scanning electron microscopy (SEM), X‐ray diffraction (XRD), and X‐ray photoelectron spectroscopy (XPS). The results showed that the precipitate morphology was impacted by the composition of the electrolytes and the purity of the magnesium. Moreover, the Tafel kinetics and corrosion rates (vcorr) directly correlated with the electrolyte and the electrode material compositions, whereby both showed a general increase when the Mg‐based electrodes were employed in the presence of chloride anions. The Tafel slopes (β) obtained for the oxygen reduction reaction (ORR) with the poly‐Pt electrode showed a significant difference between the forward and reverse potential scans in the various electrolytes used, a finding which was mainly attributed to the adsorption of hydroxide species, alkali cations, and phosphate anions to the surface whereby these species blocked the ORR active sites. [ABSTRACT FROM AUTHOR]

The electrochemical recovery of phosphorus (P) from wastewater in the form of struvite (MgNH4PO4⋅6H2O) has been shown as a viable replacement for industrial phosphate-based fertilizers. Electrochemical struvite precipitation is dependent upon the oxidation of a magnesium (Mg) anode, and the corrosion process creates a dynamically changing anode surface with likely impacts on reactor performance. In this work, a scaled-up electrochemical reactor (16 L) was designed to study reactor performance over time as anode degradation caused changes to struvite production and energy demand. A concentrated synthetic wastewater was used and electrochemical precipitation was monitored from batch to batch across six separate batch reactor experiments. Generally, the scaled-up electrochemical reactor improved struvite recovery (40–54%) over our previously reported lab-scale reactor (38%); however, the production exponentially decreased with the number of batch experiments from ~ 320 to ~ 210 g/batch, while the consumed energy exponentially increased from 0.9 to 1.6 kWh/batch due to severe degradation of the Mg anode. FTIR, XRD, SEM, XPS, and chemical analyses confirmed a total production of ~ 1.6 kg of high-quality struvite with an energy input of 4.6 kwh kg−1. [ABSTRACT FROM AUTHOR]

A number of approaches are proposed and assessed to reduce the frozen natural orbital (FNO) truncation error of coupled-cluster singles and doubles with perturbative triples [CCSD(T)] energies. The diagrammatic energy decomposition method of Irmler and Grüneis [J. Chem. Phys. 151, 104107 (2019)] is extended to the FNO truncation correction of the particle-particle ladder (PPL) term in the case of closed- and open-shell molecular systems. The approach is tested for reaction, interaction, and atomization energies, and it is found the most robust for a wider range of FNO truncation thresholds outperforming the commonly employed additive MP2 correction. We also show that the linear extrapolation (LE) of FNO-CCSD(T) energies as a function of second-order Møller–Plesset (MP2) energies provides the best correlation energies and most balanced energy differences with tighter FNO thresholds, but it lacks systematic error compensation that would be required for the better performance with looser FNO thresholds. Further insight is gained from a diagrammatic and spin-component decomposition based analysis. Moreover, orbital (pair) specific energy decompositions are utilised to introduce size-consistent variants of the promising PPL and LE FNO corrections and their analogues for (T), which are also readily applicable in the context of popular local correlation methods. [ABSTRACT FROM AUTHOR]

Intensive common carp (Cyprinus carpio L.) pond production offers an alternative to traditionally practiced extensive and semi-intensive farming technologies. Global warming increases the scarcity of water available for aquaculture, requiring increased productivity per unit of used water. The present trial was conducted on intensive rearing of two-summer-old common carp (0.5 ± 0.1) kg. Fractional factorial design (24–1, resolution IV) was applied to identify how production performance is affected by the following four factors and their interactions: I) feeding rate: ad libitum (4%) vs. restricted (2%); II) stocking density: low (1.1 t/ha) vs. high (2.2 t/ha); III) aeration rate: low (11 kW/ha) vs. high (25 kW/ha); and IV) presence or absence of co-cultured species: monoculture vs. polyculture with pikeperch (Sander lucioperca L.) reared in cages. The feeding rate appeared to be the most influential factor in growth, meat quality, water quality, and stress parameters. Although the higher stocking density might be economically justified in the short term, due to impaired welfare it brings risks in the long run. The higher rate of artificial aeration showed a negative effect on meat and water quality; however, its cooling effect might be helpful in tackling issues with extreme water temperature. The test showed feasible cage production of pikeperch even in intensive pond production. The recommended goals for feasible intensification of common carp pond aquaculture are feeding regimes aiming at better feed utilization instead of growth maximization, stocking densities up to the limits of fish welfare (gross yield <11 t/ha), optimized paddle wheel aeration in favor of algae development (<11 kW/ha), and species/technology diversification. • Intensive pond-rearing system of common carp with gross yield up to 11 t/ha. • Feeding rate as the most important factor for common carp performance and welfare • Feasible intensive pond production of common carp with pikeperch in cage units • Artificial aeration, stocking density, and feeding level can affect water temperature. [ABSTRACT FROM AUTHOR]

• G4 DNA wires mediate electron transfer (ET) between gold and G4-bound methylene blue (MB). • G4 DNA wires were tethered to gold electrodes via 4 phosphorothioated adenosine tags. • ET rate constant k s of 155 s−1 beats 74 s−1 shown for (dGdC) 20 , approaching 184 s−1 of (dAdT) 25. • This k s is well below 108 s−1 determined by the current-voltage measurements with no MB. • Complex H+/2e− electrochemistry of MB obstructed kinetic analysis of ET along G4 wires. G-quadruplex (G4) DNA wires are perspective highly-conductive building blocks for self-assembling bioelectronic nanocircuits. Here, we interrogated electrochemically G4-mediated electron transfer (ET) reaction between the gold electrodes and redox indicator methylene blue (MB) intercalated into ten-tetrade G4 DNA tethered to the gold electrode via four phosphorothioated adenosine tags. The efficiency of DNA-mediated ET evaluated by kinetic analysis of MB redox transformations was characterized by the k s of 155 s−1. This value was well below 108 s−1 per ten tetrades determined by the current-voltage measurements in the absence of any redox active species, primarily. Due to the complex 2e−/1H+ electrochemistry of MB that apparently gated the overall ET reaction. However, it was superior to 74 s−1 found for MB intercalated into (dGdC) 20 duplexes and close to 184 s−1 estimated for MB groove-bound to (dAdT) 25. The ET-mediating efficiency of highly hydrated G4 wires was thus superior to the electronically-corrupted and water-poor dGdC duplexes and approaching that of dAdT-rich DNA. We show that the electrical properties of G4 DNA wires assessed electrochemically with MB as a redox probe differ essentially from those measured in the absence of redox indicators, indicating that the electrochemical reaction of the redox probe intercalating/interacting with the G4 DNA wires limits the overall kinetics of ET through the wire. [Display omitted] [ABSTRACT FROM AUTHOR]

The cytokine release syndrome or cytokine storm, which is the hyper-induction of inflammatory responses has a central role in the mortality rate of COVID-19 and some other viral infections. Interleukin-6 (IL-6) is a key player in the development of cytokine storms. Shedding of interleukin-6 receptor (IL-6Rα) results in the accumulation of soluble interleukin-6 receptors (sIL-6R). Only relatively few cells express membrane-bound IL-6Rα. However, sIL-6R can act on potentially all cells and organs through the ubiquitously expressed gp130, the coreceptor of IL-6Rα. Through this, so-called trans-signaling, IL-6–sIL-6R is a powerful factor in the development of cytokine storms and multiorgan involvement. Some bacteria (e.g., Serratia marcescens, Staphylococcus aureus, Pseudomonas aeruginosa, Listeria monocytogenes), commonly considered to cause co-infections during viral pneumonia, can directly induce the shedding of membrane receptors, including IL-6Rα, or enhance endogenous shedding mechanisms causing the increase of sIL-6R level. Here we hypothesise that bacteria promoting shedding and increase the sIL-6R level can be an important contributing factor for the development of cytokine storms. Therefore, inhibition of IL-6Rα shedding by drastically reducing the number of relevant bacteria may be a critical element in reducing the chance of a cytokine storm. Validation of this hypothesis can support the consideration of the prophylactic use of antibiotics more widely and at an earlier stage of infection to decrease the mortality rate of COVID-19. Dm4iGs5nWD8FkGrYCfJL2M Video abstract [ABSTRACT FROM AUTHOR]

Assigning species to functional response groups in phytoplankton ecology reduces the number of functional units, which helps understand the processes that shape diversity and functioning of planktonic assemblages. Although the concept has become widespread in recent years, numerical characterization of the groups' positions in the niche space remained a challenging task. Using a large river phytoplankton dataset, we characterized the functional groups (FGs) of phytoplankton by their niche position and niche breadth in the niche space defined by the relevant environmental variables using the Outlying Main Index approach. The niche space has been defined primarily by trophic-related (nutrients) and river size-related variables (water residence time, discharge). Although we hypothesized that FGs with central niche position would have wide, while those with marginal niche position have narrow niche breadth, these have not been corroborated by the results. Rather, FGs occurred both with central niche position and intermediate breadth, as well as with marginal niche position and wide breadth. Niche position of several FGs was different from that suggested by their known habitat templates in lakes. Furthermore, we found no significant relationship between niche position and niche breadth, suggesting that the occurrence of FGs in rivers is simultaneously influenced by both niche characteristics. [ABSTRACT FROM AUTHOR]

During the outbreak of the six-day „blitzkrieg” on 5 June 1967, the Arab world was severely defeated. The defeat also signified the failure of the allies of Egypt and Syria: the Soviet Union and the socialist countries as well. Hungarian political leaders continued to offer their support to the Arab nations affected by the Israeli aggression, however, they also criticised certain Arab politicians (Syrians and the leader of the Palestine Liberation Organization – PLO) for their extremist, reckless and often demagogic statements. International public opinion was mixed. Some elements were sceptical about support for the Arabs as they were badly defeated in a short time in contrast to the heroic fight for Vietnamese independence in the early 1950s. [ABSTRACT FROM AUTHOR]

DNA-mediated electron transfer (ET) underlies a variety of bioelectronics applications, and, thus, simple approaches for its kinetic analysis are required. Here, electrocatalysis of a ferricyanide reduction catalyzed by methylene blue (MB) bound to either (dGdC) 20 or (dAdT) 25 duplexes tethered to gold via an alkanethiol linker was voltammetrically studied at stationary electrodes, and its kinetics was analyzed by two theoretical models. A thin layer voltammetry analysis, assuming that the reaction occurs within the l -nm thick layer formed by the DNA duplexes of the length l , yielded the electrocatalytic rate constant k 1 of (2.1 ± 0.4)105 and (2.4 ± 0.5)106 M−1 s−1, for (dGdC) 20 and (dAdT) 25. The sequence-specific k 1 values were consistent with structural differences of (dGdC) 20 or (dAdT) 25 at the negatively polarized interface and approached the k 1 previously reported for the rotating disk electrode system (Angew. Chemie Int. Ed. 58 (2019) 3048). These results offer new tools for immediate kinetic analysis of electrocatalytic reactions involving long-range ET along the DNA duplexes, the tools that allow differentiating electrical properties of nucleic acids in the most convenient and simple way. Image 1 • Electrocatalysis of [Fe(CN) 6 ]3- reduction by DNA-bound methylene blue was studied. • Kinetics of electrocatalysis was assessed by thin-layer voltammetry at stationary electrodes. • Theoretical approach allowed evaluation of DNA-mediated electron transfer (ET) rates. • Evaluated reaction rates were consistent with those obtained in the rotating disk electrode system. • Results offer simple tools for kinetic analysis of electrocatalysis involving DNA-mediated ET. [ABSTRACT FROM AUTHOR]

Electrical properties of self‐assembling DNA nanostructures underlie the paradigm of nanoscale bioelectronics, and as such require clear understanding. DNA‐mediated electron transfer (ET) from a gold electrode to DNA‐bound Methylene Blue (MB) shows directional preference, and it is sequence‐specific. During the electrocatalytic reduction of [Fe(CN)6]3− catalyzed by DNA‐bound MB, the ET rate constant for DNA‐mediated reduction of MB reaches (1.32±0.2)103 and (7.09±0.4)103 s−1 for (dGdC)20 and (dAdT)25 duplexes. The backward oxidation process is less efficient, making the DNA duplex a molecular rectifier. Lower rates of ET via (dGdC)20 agree well with its disturbed π‐stacked sub‐molecular structure. Such direction‐ and sequence‐specific ET may be implicated in DNA oxidative damage and repair, and be relevant to other polarized surfaces, such as cell membranes and biomolecular interfaces. [ABSTRACT FROM AUTHOR]

Electrical properties of self‐assembling DNA nanostructures underlie the paradigm of nanoscale bioelectronics, and as such require clear understanding. DNA‐mediated electron transfer (ET) from a gold electrode to DNA‐bound Methylene Blue (MB) shows directional preference, and it is sequence‐specific. During the electrocatalytic reduction of [Fe(CN)6]3− catalyzed by DNA‐bound MB, the ET rate constant for DNA‐mediated reduction of MB reaches (1.32±0.2)103 and (7.09±0.4)103 s−1 for (dGdC)20 and (dAdT)25 duplexes. The backward oxidation process is less efficient, making the DNA duplex a molecular rectifier. Lower rates of ET via (dGdC)20 agree well with its disturbed π‐stacked sub‐molecular structure. Such direction‐ and sequence‐specific ET may be implicated in DNA oxidative damage and repair, and be relevant to other polarized surfaces, such as cell membranes and biomolecular interfaces. Current events: DNA‐mediated long‐range ET in gold‐tethered DNA duplexes shows directional preference for reduction, thereby making DNA a molecular rectifier. [ABSTRACT FROM AUTHOR]

ABSTRACT: Complex multicellularity represents the most advanced level of biological organization and it has evolved only a few times: in metazoans, green plants, brown and red algae and fungi. Compared to other lineages, the evolution of multicellularity in fungi follows different principles; both simple and complex multicellularity evolved via unique mechanisms not found in other lineages. Herein we review ecological, palaeontological, developmental and genomic aspects of complex multicellularity in fungi and discuss general principles of the evolution of complex multicellularity in light of its fungal manifestations. Fungi represent the only lineage in which complex multicellularity shows signatures of convergent evolution: it appears 8–11 times in distinct fungal lineages, which show a patchy phylogenetic distribution yet share some of the genetic mechanisms underlying complex multicellular development. To explain the patchy distribution of complex multicellularity across the fungal phylogeny we identify four key observations: the large number of apparently independent complex multicellular clades; the lack of documented phenotypic homology between these clades; the conservation of gene circuits regulating the onset of complex multicellular development; and the existence of clades in which the evolution of complex multicellularity is coupled with limited gene family diversification. We discuss how these patterns and known genetic aspects of fungal development can be reconciled with the genetic theory of convergent evolution to explain the pervasive occurrence of complex multicellularity across the fungal tree of life. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizae (AM) are the most frequent symbioses of land plants. By reisolating a long-lost fungus from nature, a new study cracks the genomics of an enigmatic fungal–cyanobacterial partnership and reestablishes a valuable model for understanding the AM symbiosis. [ABSTRACT FROM AUTHOR]

Introduction: Non-responders to cardiac resynchronization therapy (CRT-NR) have poor prognosis. Sacubitril/valsartan (SV) treatment improved the outcome of patients with heart failure with reduced left ventricular (LV) ejection fraction (HFrEF) in randomized trials with no data on the specific cohort of CRT-NRs. The aim of this study was to compare the echocardiographic and biomarker changes in CRT-NR patients treated with versus without SV, and in patients with HFrEF on SV therapy. Methods: CRT-NR patients initiated on SV (group I), CRT-NR patients on angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (ACEi/ARB) (group II), and patients with HFrEF (without CRT) initiated on SV (group III) were identified in our heart failure (HF) registry. CRT-NR was defined as < 10% improvement in left ventricular ejection fraction (LV EF) 6 months after the implantation. Echocardiographic parameters and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels at baseline and at the end of follow-up were compared. Results: A total of 275 patients (group I, 70; group II, 70; and group III, 135) were included. After a follow-up of 7.54 ± 1.8 months (mean ± standard deviation [SD]), LV EF (%) increased in group I (25.2 ± 5.7 versus 29.4% ± 6.7; p < 0.001) and in group III (26.6 ± 6.4 versus 29.9 ± 6.7; p < 0.001). LV end-systolic diameters (mm) decreased in group I (56.6 ± 9.0 versus 54.3 ± 8.7; p = 0.004) and in group III (55.9 ± 9.9 versus 54.3 ± 11.2; p = 0.021). The levels of NT-proBNP (pg/mL) decreased in group I (2058.86 [1041.07–4502.51] versus 1121.55 [545–2541]; p < 0.001) and in group III (2223.35 [1233.03–4795.96] versus 1123.09 [500.38–2651.27]; p < 0.001). The extent of improvement was similar in groups I and III (p > 0.05). No significant changes were detected in group II. Conclusion: SV therapy induced similar improvements in echocardiographic parameters and in NT-proBNP levels in CRT-NR patients and in patients with HFrEF without resynchronization. [ABSTRACT FROM AUTHOR]

A robust and sensitive electrochemical assay for chrononocoulometric detection of nucleic acids at a single nucleotide polymorphism (SNP) level has been developed. The assay exploits hybridization-induced conformational switching of gold-tethered TP53-specific 33-mer and truncated 20-mer hairpin DNA probes and methylene blue (MB) as an intercalating redox indicator. We show that by fine tuning of MB-DNA intercations the enhanced binding of MB to hybrids formed with a cancer-biomarker sequence can be achieved, and that results in robust “off-on” sensing of hybridization, while the stem-loop probe design allows minimized, independent of the DNA length background signals. Both DNA probes were sensitive to the presence of SNP in the targeted DNA sequence already at 10 pM. DNA levels, and the robust “off-on” discrimination of 10 pM perfectly-matched DNA from 50 nM SNP-containing DNA was achieved by time-adjusted chronocoulometry. This label-free hairpin DNA strategy allows systematic design of DNA assays for fast, robust and inexpensive genetic analysis in excessive mixtures of structurally-related DNA sequences and was used for specific analysis of prostate-cancer-realted cellular microRNA in total RNA samples isolated from LNCaP and BPH1 cells. [ABSTRACT FROM AUTHOR]

Peroxidase-mimicking catalytic DNAzyme labels comprising hemin-guanine quadruplex (G4) complexes are widely used in electrochemical DNA and aptamer assays. However, their catalytic activity and thus the assay performance may be limited by the complex stability. Here, electrochemical properties of the hemin-G4 complexes with hemin covalently attached to the G4 sequence (covalent complexes) and of the non-covalent hemin-G4 complexes were studied and compared in the reaction of electrocatalytic reduction of H 2 O 2 . At pH 7, non-covalently and covalently bound hemin-G4 complexes immobilized on gold electrodes showed formal potentials of − 242 and − 220 mV vs. Ag/AgCl, being less negative than − 316 mV exhibited by hemin attached to the alkanethiol SAM. Both complexes were able to electrocatalytically reduce H 2 O 2 starting from 0.4 V, and O 2 – from 0.15 V. In the reaction of H 2 O 2 reduction at 0.2 V, within the potential window of no interference from O 2 , the covalent hemin-G4 complex showed a 20 fold higher specific electrocatalytic activity compared to the non-covalent analogue and the K M (towards H 2 O 2 ) of 0.58 mM (2 mM for the non-covalent complex). Both the enhanced catalytic activity and sensitivity for H 2 O 2 were ascribed to the higher integrity/stability of the covalent complexes. The results open new biosensor perspectives for the covalent hemin-G4 complexes as more stable and active labels for DNA and aptamer assays. [ABSTRACT FROM AUTHOR]

Purpose/Aim: Autologous cultivated oral mucosal (OM) epithelial transplantation has been successfully used as corneal epithelial replacement in bilateral limbal stem cell deficiency. Recently, lotrafilcon A contact lens (CL) surface was described as a suitable carrier for cultured stem cells in corneal epithelial transplantation. Our aim was to establish explant cultures from human OM on CL carriers that are free of animal-derived materials and feeder cells. Materials and methods: Human cadaveric 2 mm OM explants were sutured onto CL surfaces and cultivated with fetal calf serum (FCS) or human serum (HS) supplemented culture medium without feeder cells. Confluent cultures were harvested and evaluated morphologically with hematoxylin and eosin stain and with immunofluorescence microscopy for the presence of p63, vimentin and cytokeratins (CK) 3, 4, 13 and 14. Results: Confluent cell sheets covering the whole CL surface were produced from OM explants after 2 weeks of culture with HS and after 3 weeks with FCS. A basal layer consisted of small, vimentin, p63 and CK14 positive putative stem/progenitor cells, which were present in the whole cell sheet. Large, CK3, CK4 and CK13 positive, differentiated cells appeared to spread above this confluent layer. Conclusions: We have established an animal-free culture system from human OM explants on CL surface. The cultured OM sheets contain large numbers of putative stem cells including limbal-like CK3 and CK14 positive cells. This method can be adapted to good manufacturing practice (GMP) conditions and has, therefore, great potential for clinical use. [ABSTRACT FROM PUBLISHER]

Unique electronic and ligand recognition properties of the DNA double helix provide basis for DNA applications in biomolecular electronic and biosensor devices. However, the relation between the structure of DNA at electrified interfaces and its electronic properties is still not well understood. Here, potential-driven changes in the submolecular structure of DNA double helices composed of either adenine-thymine (dAdT)25 or cytosine-guanine (dGdC)20 base pairs tethered to the gold electrodes are for the first time analyzed by in situ polarization modulation infrared reflection absorption spectroscopy (PM IRRAS) performed under the electrochemical control. It is shown that the conformation of the DNA duplexes tethered to gold electrodes via the C6 alkanethiol linker strongly depends on the nucleic acid sequence composition. The tilt of purine and pyrimidine rings of the complementary base pairs (dAdT and dGdC) depends on the potential applied to the electrode. By contrast, neither the conformation nor orientation of the ionic in character phosphate-sugar backbone is affected by the electrode potentials. At potentials more positive than the potential of zero charge (pzc), a gradual tilting of the double helix is observed. In this tilted orientation, the planes of the complementary purine and pyrimidine rings lie ideally parallel to each other. These potentials do not affect the integral stability of the DNA double helix at the charged interface. At potentials more negative than the pzc, DNA helices adopt a vertical to the gold surface orientation. Tilt of the purine and pyrimidine rings depends on the composition of the double helix. In monolayers composed of (dAdT)25 molecules the rings of the complementary base pairs lie parallel to each other. By contrast, the tilt of purine and pyrimidine rings in (dGdC)20 helices depends on the potential applied to the electrode. Such potential-induced mobility of the complementary base pairs can destabilize the helix structure at a submolecular level. These pioneer results on the potential-driven changes in the submolecular structure of double stranded DNA adsorbed on conductive supports contribute to further understanding of the potential-driven sequence-specific electronic properties of surface-tethered oligonucleotides. [ABSTRACT FROM AUTHOR]

Flood damage poses a major threat to many countries across Europe. One of the most disadvantageous communities is Hungary, especially in view of the fact that 23% of the total area is situated on floodplain. 97% of this region is protected by flood control dikes and the remaining 3% is generally low-value zone. Through the decades different design methods referring to flood protection dikes have been recommended with newer and newer safety factors. In a few areas of geotechnical engineering - with the presence of Eurocode 7 - the reliability based design came to the front. The performance of a certain embankment cannot be compared by considering only the safety factors of the different theories but based on computing the probability of failure values it becomes possible. The article aims to show a method of how to define the input parameters and calculate the probability of failure of a flood protection dike. Hence the reliability of different standards can be compared. [ABSTRACT FROM AUTHOR]

We present a novel "on-off", cost-effective, rapid electrochemical aptasensor combined with a microfluidics cartridge system for the detection of Δ9-THC (Δ9-tetrahydrocannabinol) in human saliva via differential pulse voltammetry. The assay relied on the competitive binding between the Δ9-THC and a soluble redox indicator methylene blue, using an aptamer selected via FRELEX. We found that the aptasensor can detected 1 nM of Δ9-THC in PBS in a three-electrode cell system, while the sensitivity and both the dissociation constant (K d) and association constant (K b) were dependent on the aptamer density. The aptamer also showed great affinity towards Δ9-THC when tested against cannabinol and cannabidiol. The same limit of detection of 1 nM in PBS was achieved in small volume samples (∼60 μL) using the aptamer-modified gold screen-printed electrodes combined with the microfluidic cartridge setup, however, the presence of 10% raw human saliva had a negative effect which manifested in a 10-fold increase in the LOD due to interfering elements. Filtering the saliva, improved the tested volume to 50% and the LOD to 5 nM of Δ9-THC which is lower than the concentrations associated with impairment (6.5–32 nM). The aptasensor showed a good storage capability up to 3 days, however, the reusability significantly dropped from 10 cycles (freshly prepared) to 5 cycles. The results clearly demonstrate the feasibility of the aptasensor platform with the microfluidics chamber towards a point-of-care testing application for the detection of Δ9-THC in saliva. [Display omitted] [ABSTRACT FROM AUTHOR]

A new approach is proposed to reduce the basis set incompleteness error of the triple excitation correction in explicitly correlated coupled-cluster singles and doubles with perturbative triples calculations. Our method is similar to the intuitive triples correction approach of Knizia et al. [J. Chem. Phys. 130, 054104 (2009)] but, in contrast to the latter, is size-consistent. The new approximation is easy to implement, and its overhead is negligible with respect to the conventional (T) correction. The performance of the approach is assessed for atomization, reaction, and interaction energies as well as for bond lengths and harmonic vibrational frequencies. The advantages of its size consistency are also demonstrated. [ABSTRACT FROM AUTHOR]

When it comes to flood protection, the established method is to use an impermeable material in dikes, to prevent seepage. This material is usually some type of clayey soil which is considered as watertight and erosion-resistant. Despite that, in many occasions not only seepage, but the failure of the dam occurred due to surface erosion, because dispersive behavior is barely investigated, and their presence are not considered during the phase of design. The term "dispersive clay" refer to a cohesive soil, which has an unfavorable property compared to other clays. Therefore the application of these kind of clays in flood protection structures, like dikes cannot be considered as a solution for the seepage problems. Dikes constructed from dispersive soils often fail to achieve the main idea of flood protection: keeping the downstream face relatively dry. Earlier experiences stated that the dispersive behavior is related to the physico-chemical composition of the soil, therefore in this paper a few Hungarian soils, which are identified as dispersive are examined with geotechnical, agricultural and phase analytical methods. [ABSTRACT FROM AUTHOR]

This study is the first pharmacological characterization of the novel chemical entity, ORM-3819 ( L -6-{4-[N'-(4-Hydroxi-3-methoxy-2-nitro-benzylidene)-hydrazino]-phenyl}-5-methyl-4,5-dihydro-2 H-pyridazin-3-one), focusing primarily on its cardiotonic effects. ORM-3819 binding to cardiac troponin C (cTnC) was confirmed by nuclear magnetic resonance spectroscopy, and a selective inhibition of the phosphodiesterase III (PDE III) isozyme (IC 50 =3.88±0.3 nM) was revealed during in vitro enzyme assays. The Ca 2+ -sensitizing effect of ORM-3819 was demonstrated in vitro in permeabilized myocyte-sized preparations from left ventricles (LV) of guinea pig hearts (ΔpCa 50 =0.12±0.01; EC 50 =2.88±0.14 µM). ORM-3819 increased the maximal rate of LV pressure development (+dP/dt max ) (EC 50 =8.9±1.7 nM) and LV systolic pressure (EC 50 =7.63±1.74 nM) in Langendorff-perfused guinea pig hearts. Intravenous administration of ORM-3819 increased LV+dP/dt max (EC 50 =0.13±0.05 µM/kg) and improved the rate of LV pressure decrease (−dP/dt max ); (EC 50 =0.03±0.02 µM/kg) in healthy guinea pigs. In an in vivo dog model of myocardial stunning, ORM-3819 restored the depressed LV+dP/dt max and improved % segmental shortening (%SS) in the ischemic area (to 18.8±3), which was reduced after the ischaemia-reperfusion insult (from 24.1±2.1 to 11.0±2.4). Our data demonstrate ORM-3819 as a potent positive inotropic agent exerting its cardiotonic effect by a cTnC-dependent Ca 2+ -sensitizing mechanism in combination with the selective inhibition of the PDE III isozyme. This dual mechanism of action results in the concentration-dependent augmentation of the contractile performance under control conditions and in the postischemic failing myocardium. [ABSTRACT FROM AUTHOR]

Platelet derived growth factor receptors (PDGFR) play an important role in tumor pathogenesis and are frequently overexpressed in glioblastoma. Earlier we have shown that only confluent glioblastoma cell cultures exhibit a biphasic calcium transient upon PDGF stimulation. Here, we examined how the change in cell density leads to differential cellular responses to the same PDGF stimulus. PDGF beta receptors and their specific phosphotyrosine residues were fluorescently co-labeled on A172 and T98G glioblastoma cells. The distribution in cell membrane microdomains (lipid rafts) and the phosphorylation state of PDGFR was measured by confocal microscopy and quantitated by digital image processing. Corresponding bulk data were obtained by Western blotting. Activation of relevant downstream signaling pathways was assessed by immunofluorescence in confocal microscopy and by Western blot analysis. Functional outcomes were confirmed with bulk and single cell proliferation assays and motility measurements. In non-confluent (sparse) cultures PDGF-BB stimulation significantly increased phosphorylation of Tyr716 specific for the Ras/MAPK pathway and Tyr751 specific for the phosphoinositide 3-kinase/Akt pathway. As cell monolayers reached confluence, Tyr771 and Tyr1021 were the prominently phosphorylated residues. Tyr771 serves as adaptor for Ras-GAP, which inactivates the MAPK pathway, and Tyr1021 feeds into the phospholipase C-gamma/PKC pathway. Coherent with this, MAPK phosphorylation, Ki-67 positivity and proliferation dominated in dispersed cells, and could be abolished with inhibitors of the MAPK pathway. At the same time, RhoA activation, redistribution of cortactin to leading edges, and increased motility were the prominent output features in confluent cultures. Importantly, the stimulus-evoked confluence-specific changes in the phosphorylation of tyrosine residues occurred mainly in GM1-rich lipid microdomains (rafts). These observations suggest that the same stimulus is able to promote distinctly relevant signaling outputs through a confluence dependent, lipid raft-based regulatory mechanism. In particular, cell division and survival in sparse cultures and inhibition of proliferation and promotion of migration in confluent monolayers. In our model, the ability to switch the final output of the same stimulus as a function of cell density could be a key to the balance of proliferation and invasion in malignant glioblastoma. [ABSTRACT FROM AUTHOR]

Photothermal characteristics and light-induced structural (volume) changes of carotenoid-containing and noncontaining photosynthetic reaction centers (RCs) were investigated by wide frequency band hydrophone. We found that the presence of carotenoid either does not play considerable role in the light-induced conformational movements, or these rearrangements are too slow for inducing a photoacoustic ( PA) signal. The kinetic component with a few tens of microseconds, exhibited by the carotenoid-less RCs, appears to be similar to that of triplet state lifetimes, identified by other methods. The binding of terbutryn to the acceptor side is shown to affect the dynamics of the RC. Our results do not confirm large displacements or volume changes induced by the charge movements and by the charge relaxation processes in the RCs in few hundreds of microseconds time scale that accompanies the electron transfer between the primary and secondary electron acceptor quinones. [ABSTRACT FROM AUTHOR]

• Electrochemical synthesis of struvite used a pure Mg anode. • Synthetic wastewater with Cl− background was used as test solution. • Pitting potential saturates to a minimum at Cl− ≥ 1000 mM. • Higher corrosion rate was obtained at pH 8. • 98% phosphate recovery was achieved in Cl− ≥1000 mM at pH 8. Electrochemical recovery of phosphorus from synthetic wastewater using a sacrificial Mg anode has been explored as a function of key parameters, including pH, voltage, and salinity. The effect of chloride (NaCl) concentrations in the range of 0–1500 mM on both Mg corrosion and phosphate precipitation was investigated in acidic and alkaline (i.e., pH 4 and 8) solutions of dihydrogen ammonium phosphate. The primary phosphate precipitate was expected to be struvite (MgNH 4 PO 4 ·6H 2 O), and collected precipitates were characterized to determine composition and phase. Batch experiments were run at selected potentials identified by linear sweep voltammetry experiments. Higher corrosion current densities (j corr), which indicated higher Mg dissolution and corrosion rates (υ corr), were achieved in solutions with higher pH and salt concentrations. Both Mg corrosion and phosphate recovery were proportional to [Cl−], so 1500 mM Cl− at pH 8 resulted in increased Mg dissolution and phosphate recovery by ∼5x and 2x, respectively, compared to the solution without chloride. Elemental composition analysis (ion chromatography), crystallography (X-ray diffraction), surface chemical composition analysis (Fourier-transform infrared spectrometry) and characterization (scanning electron microscopy images) of precipitates suggested the presence of struvite. The Mg/P composition of precipitates formed in 1000 mM Cl− solution showed a greater extent of deviation from the theoretical molar ratio in struvite when the electrochemical cell was operated at more positive anodic overpotential and low initial solution pH. The elevated Mg/P ratio could indicate the presence of mixed precipitates. Simulation of product distribution analysis and specific energy requirement results suggest optimum electrochemical struvite production in the pH range of 8–10 in the presence of chloride. [Display omitted] [ABSTRACT FROM AUTHOR]

Protein biomarkers of cancer allow a dramatic improvement in cancer diagnostics as compared to the traditional histological characterisation of tumours by enabling a non-invasive analysis of cancer development and treatment. Here, an electrochemical label-free assay for urokinase plasminogen activator (uPA), a universal biomarker of several cancers, has been developed based on the recently selected uPA-specific fluorinated RNA aptamer, tethered to a gold electrode via a phosphorothioated dA tag, and soluble redox indicators. The binding properties of the uPA–aptamer couple and interference from the non-specific adsorption of bovine serum albumin (BSA) were modulated by the electrode surface charge. A nM uPA electroanalysis at positively charged surfaces, complicated by the competitive adsorption of BSA, was tuned to the pM uPA analysis at negative surface charges of the electrode, being improved in the presence of negatively charged BSA. The aptamer affinity for uPA displayed via the binding/dissociation constant relationship correspondingly increased, ca. three orders of magnitude, from 0.441 to 367. Under optimal conditions, the aptasensor allowed 10−12–10−9 M uPA analysis, also in serum, being practically useful for clinical applications. The proposed strategy for optimization of the electrochemical protein sensing is of particular importance for the assessment and optimization of in vivo protein ligand binding by surface-tethered aptamers. [ABSTRACT FROM AUTHOR]

Since their discovery, carbon nanotubes (CNTs) have attracted intense attention to broad range of potential applications. In contrast to the 1D isolated single-walled carbon nanotubes (SWCNT), 2D films or bundles made of thousands of tubes have been introduced as more advantageous building blocks for new types of applications in mechanically flexible and stretchable, optically transparent electronic systems. In our experiments, we combined photosynthetic reaction centre proteins, the light energy converter units in living cells, purified from purple bacteria, with multiwalled carbon nanotube (MWCNT) bundles. The change in the conductivity of the bare MWCNT bundles and the RC/MWCNT composite after light excitation was measured and compared. We found that the electrical conductivity under light excitation depends on the intrinsic conductivity of individual tubes within the bundles and on structural characteristics, like geometry (diameter, length, spatial arrangement, interconnects, etc.) and the electronic coupling with the RCs. [ABSTRACT FROM AUTHOR]

In this study, a suite of natural wastewater sources is tested to understand the effects of wastewater composition and source on electrochemically driven nitrogen and phosphorus nutrient removal. Kinetics, electrode behavior, and removal efficiency were evaluated during electrochemical precipitation, whereby a sacrificial magnesium (Mg) anode was used to drive precipitation of ammonium and phosphate. The electrochemical reactor demonstrated fast kinetics in the natural wastewater matrices, removing up to 54% of the phosphate present in natural wastewater within 1 min, with an energy input of only 0.04 kWh.m−3. After 1 min, phosphate removal followed a zero-order rate law in the 1 min - 30 min range. The zero-order rate constant (k) appears to depend upon differences in wastewater composition, where a faster rate constant is associated with higher Cl− and NH 4 + concentrations, lower Ca2+ concentrations, and higher organic carbon content. The sacrificial Mg anode showed the lowest corrosion resistance in the natural industrial wastewater source, with an increased corrosion rate (v corr) of 15.8 mm.y−1 compared to 1.9–3.5 mm.y−1 in municipal wastewater sources, while the Tafel slopes (β) showed a direct correlation with the natural wastewater composition and origin. An overall improvement of water quality was observed where important water quality parameters such as total organic carbon (TOC), total suspended solids (TSS), and turbidity showed a significant decrease. An economic analysis revealed costs based upon experimental Mg consumption are estimated to range from 0.19 $.m−3 to 0.30 $.m−3, but costs based upon theoretical Mg consumption range from 0.09 $.m−3 to 0.18 $.m−3. Overall, this study highlights that water chemistry parameters control nutrient recovery, while electrochemical treatment does not directly produce potable water, and that economic analysis should be based upon experimentally-determined Mg consumption data. Synopsis Statement: Magnesium-driven electrochemical precipitation of natural wastewater sources enables fast kinetics for phosphate removal at low energy input. [Display omitted] [ABSTRACT FROM AUTHOR]

Sections Lanatuli and Atramentarii of the genus Coprinopsis contain some of the best known and most important agaric species, including C. cinerea and C. lagopus, yet a critical, phylogeny-based assessment of the species limits has not been carried out. Taxa have been characterized chiefly on the basis of morphological characters, which however show little discriminatory power and/or considerable overlap between several species pairs. We used ITS and LSU sequence data of 29 described taxa in Coprinopsis sections Lanatuli and Atramentarii to infer species limits and the correspondence between morphological characters and species lineages, as well as to examine the phylogenetic affinities of sections Lanatuli and Atramentarii. Our analyses recovered three large clades, implying a paraphyly for section Lanatuli. Based on morphology and clade structure, we estimate ca. 38 species in the two sections, including several potentially new taxa, three of which are described herein. Coprinopsis pachyderma, C. lagopus var. vacillans, C. acuminata, C. spelaiophila, Coprinus citrinovelatus and Cop. brunneistrangulatus were found to be synonymous with other, earlier described species. Congruent with previous mating studies, our analyses recovered multiple, morphologically indistinguishable lineages within C. lagopus, which included C. lagopus var. vacillans, an ephemeral, developmental variant. Morphological traits supporting the inferred clade structure are discussed. Three new taxa (C. fusispora, C. babosiae, C. villosa), and one new combination (C. mitraespora) are proposed. [ABSTRACT FROM AUTHOR]

Rapidly evolving, indel-rich phylogenetic markers play a pivotal role in our understanding of the relationships at multiple levels of the tree of life. There is extensive evidence that indels provide conserved phylogenetic signal, however, the range of phylogenetic depths for which gaps retain tree signal has not been investigated in detail. Here we address this question using the fungal internal transcribed spacer (ITS), which is central in many phylogenetic studies, molecular ecology, detection and identification of pathogenic and non-pathogenic species. ITS is repeatedly criticized for indel-induced alignment problems and the lack of phylogenetic resolution above species level, although these have not been critically investigated. In this study, we examined whether the inclusion of gap characters in the analyses shifts the phylogenetic utility of ITS alignments towards earlier divergences. By re-analyzing 115 published fungal ITS alignments, we found that indels are slightly more conserved than nucleotide substitutions, and when included in phylogenetic analyses, improved the resolution and branch support of phylogenies across an array of taxonomic ranges and extended the resolving power of ITS towards earlier nodes of phylogenetic trees. Our results reconcile previous contradicting evidence for the effects of data exclusion: in the case of more sophisticated indel placement, the exclusion of indel-rich regions from the analyses results in a loss of tree resolution, whereas in the case of simpler alignment methods, the exclusion of gapped sites improves it. Although the empirical datasets do not provide to measure alignment accuracy objectively, our results for the ITS region are consistent with previous simulations studies alignment algorithms. We suggest that sophisticated alignment algorithms and the inclusion of indels make the ITS region and potentially other rapidly evolving indel-rich loci valuable sources of phylogenetic information, which can be exploited at multiple taxonomic levels. [ABSTRACT FROM AUTHOR]

Grain size and grain distribution by size are dominant factors determining soil behaviour. The shape and position of a grain distribution curve contain implicit information about the propensity of sand boiling or piping at flood conditions. The author used 1040-grain distribution curves taken from 12 sand boil locations to study the relationship between sand boils, hydraulic soil failures and entropy. The results have justified the hypotheses and indicated some fairly important details for practical consideration. Calculating grain distribution entropy is not "magic" with mathematics: it simply helps put the expected behaviour of soils into a different perspective and promotes orientation for classifying soils according to a new parameter related to grain movement. [ABSTRACT FROM AUTHOR]

Bursts of diversification are known to have contributed significantly to the extant morphological and species diversity, but evidence for many of the theoretical predictions about adaptive radiations have remained contentious. Despite their tremendous diversity, patterns of evolutionary diversification and the contribution of explosive episodes in fungi are largely unknown. Here, using the genus Coprinellus (Psathyrellaceae, Agaricales) as a model, we report the first explosive fungal radiation and infer that the onset of the radiation correlates with a change from a multilayered to a much simpler defense structure on the fruiting bodies. We hypothesize that this change constitutes a key innovation, probably relaxing constraints on diversification imposed by nutritional investment into the development of protective tissues of fruiting bodies. Fossil calibration suggests that Coprinellus mushrooms radiated during the Miocene coinciding with global radiation of large grazing mammals following expansion of dry open grasslands. In addition to diversification rate–based methods, we test the hard polytomy hypothesis, by analyzing the resolvability of internal nodes of the backbone of the putative radiation using Reversible-Jump MCMC. We discuss potential applications and pitfalls of this approach as well as how biologically meaningful polytomies can be distinguished from alignment shortcomings. Our data provide insights into the nature of adaptive radiations in general by revealing a deceleration of morphological diversification through time. The dynamics of morphological diversification was approximated by obtaining the temporal distribution of state changes in discrete traits along the trees and comparing it with the tempo of lineage accumulation. We found that the number of state changes correlate with the number of lineages, even in parts of the tree with short internal branches, and peaks around the onset of the explosive radiation followed by a slowdown, most likely because of the decrease in available niches. [ABSTRACT FROM AUTHOR]

Although the fungal order Mortierellales constitutes one of the largest classical groups of Zygomycota, its phylogeny is poorly understood and no modern taxonomic revision is currently available. In the present study, 90 type and reference strains were used to infer a comprehensive phylogeny of Mortierellales from the sequence data of the complete ITS region and the LSU and SSU genes with a special attention to the monophyly of the genus Mortierella. Out of 15 alternative partitioning strategies compared on the basis of Bayes factors, the one with the highest number of partitions was found optimal (with mixture models yielding the best likelihood and tree length values), implying a higher complexity of evolutionary patterns in the ribosomal genes than generally recognized. Modeling the ITS1, 5.8S, and ITS2, loci separately improved model fit significantly as compared to treating all as one and the same partition. Further, within-partition mixture models suggests that not only the SSU, LSU and ITS regions evolve under qualitatively and/or quantitatively different constraints, but that significant heterogeneity can be found within these loci also. The phylogenetic analysis indicated that the genus Mortierella is paraphyletic with respect to the genera Dissophora, Gamsiella and Lobosporangium and the resulting phylogeny contradict previous, morphology-based sectional classification of Mortierella. Based on tree structure and phenotypic traits, we recognize 12 major clades, for which we attempt to summarize phenotypic similarities. M. longicollis is closely related to the outgroup taxon Rhizopus oryzae, suggesting that it belongs to the Mucorales. Our results demonstrate that traits used in previous classifications of the Mortierellales are highly homoplastic and that the Mortierellales is in a need of a reclassification, where new, phylogenetically informative phenotypic traits should be identified, with molecular phylogenies playing a decisive role. [ABSTRACT FROM AUTHOR]

Summary [ABSTRACT FROM AUTHOR]

Fruiting body evolution is one of the central topics in fungal evolutionary biology. A number of hypotheses have been developed to explain the contemporary diversity of fruiting body forms, but their evaluation has been hampered by the lack of well-sampled data sets and suitable statistical methods. Phylogenetic evidence of the physiological changes that accompany switches in fruiting body type is lacking, and very little is known about the age of major events of fruiting body evolution. Based on a new multigene phylogeny, by using Bayesian methods, we demonstrate the existence of correlation between a number of morphological features and switches from nondeliquescent to deliquescent (autodigesting) fruiting bodies in the mushroom family Psathyrellaceae. Our results show that switches in the anatomy of two types of spacer cells (cystidia and pseudoparaphyses) and basidia (bimorphic or monomorphic) as well as the structure of the mushroom cap follow the evolution of deliquescent fruiting bodies, which suggests strong functional linkage between these traits. We performed Bayes factor-based tests, referred hereafter to as evolutionary pathway test (EPT), to decide which of the correlated characters were gained first during evolution. The EPTs strongly suggest that deliquescence was gained first, followed after short waiting times by the other morphological features. Bayesian relaxed molecular clock analyses suggest that the various events of switching between fruiting body types occurred independently at various ages during the history of the family. The utility of two mushroom fossils (Archaemarasmius and Protomycena), the only ones with unambiguous taxonomic positions, for the calibration of agaric trees were also examined. Based on our results, we suggest that the evolutionary benefit of deliquescence may be prevention against desiccation via accelerated ontogeny of the fruiting body. Hypotheses regarding the functional significance of the correlated evolution are presented and discussed. Further, we argue that the changes in fruiting body types in mushrooms in general can be attributed to independent events (e.g., dispersal and adaptation) and not to particular geologic ages. [ABSTRACT FROM PUBLISHER]

Abstract: Recently developed comparative phylogenetic methods offer a wide spectrum of applications in evolutionary biology, although it is generally accepted that their statistical properties are incompletely known. Here, we examine and compare the statistical power of the ML and Bayesian methods with regard to selection of best-fit models of fruiting-body evolution and hypothesis testing of ancestral states on a real-life data set of a physiological trait (autodigestion) in the family Psathyrellaceae. Our phylogenies are based on the first multigene data set generated for the family. Two different coding regimes (binary and multistate) and two data sets differing in taxon sampling density are examined. The Bayesian method outperformed Maximum Likelihood with regard to statistical power in all analyses. This is particularly evident if the signal in the data is weak, i.e. in cases when the ML approach does not provide support to choose among competing hypotheses. Results based on binary and multistate coding differed only modestly, although it was evident that multistate analyses were less conclusive in all cases. It seems that increased taxon sampling density has favourable effects on inference of ancestral states, while model parameters are influenced to a smaller extent. The model best fitting our data implies that the rate of losses of deliquescence equals zero, although model selection in ML does not provide proper support to reject three of the four candidate models. The results also support the hypothesis that non-deliquescence (lack of autodigestion) has been ancestral in Psathyrellaceae, and that deliquescent fruiting bodies represent the preferred state, having evolved independently several times during evolution. [ABSTRACT FROM AUTHOR]

There is no doubt that studying the photosynthetic conversion of light into chemical energy is extremely important in many points of view: 1) technical-in order to improve the utilization of the solar energy: 2) food production - to improve the photosynthetic production of plants in agriculture: 3) ecology - keeping the primer production in ecosystems in the biosphere balanced, etc. In the photosynthetic reaction centre protein, RC, light energy is converted by a quantum yield of almost unity. There is no such a system designed by human which is able to do that. The RC purified from purple bacteria provides an extremely unique system for studying the requirements for high efficiency conversion of light into electrochemical energy. Thanks to the recent structural (e.g. crystallography (Nobel prize to Michel, Deisenhofer, Huber) and functional (Nobel prize to Marcus)) results together with the works of molecular biology, computer- and electro-techniques, a wealth of information made a relatively clear picture about the kinetics, energetics and stabilization of electron transport within this protein that opens possibilities for new generation practical applications. In this paper we provide a short summary of fields in which the reaction centre protein can be important from practical points of view. [ABSTRACT FROM AUTHOR]

Abstract: Spectrally silent conformation change after photoexcitation of photosynthetic reaction centers isolated from Rhodobacter sphaeroides R-26 was observed by the optical heterodyne transient grating technique. The signal showed spectrally silent structural change in photosynthetic reaction centers followed by the primary P+BPh− charge separation and this change remains even after the charge recombination. Without bound quinone to the RC, the conformation change relaxes with about 28μs lifetime. The presence of quinone at the primary quinone (QA) site may suppress this conformation change. However, a weak relaxation with 30–40μs lifetime is still observed under the presence of QA, which increases up to 40μs as a function of the occupancy of the secondary quinone (QB) site. [Copyright &y& Elsevier]

Photosynthetic reaction center (RC) pigment protein complex converts the free energy of light into chemical potential of charge pairs with extremely high efficiency. A transient phase in the absorption spectrum in the sub-millisecond time scale is expected to be especially important to examine the conformational gating model of the QQB to QAQ (here QA and QB are the primary and secondary quinone type electron acceptors, respectively) electron transport. Essential kinetic components at few tens of microseconds scale and at around 200 μs have been suggested. We investigated the conformation change of RCs using heterodyne detection of the laser-induced transient grating method. An about 25 μs dynamics was observed, which coincides with the one described by the conformational gating model and possibly related to the nonadiabatic intrinsic QQB to QAQ electron transport. The relative intensity of this component decreased with increasing quinone concentration indicating an initial (P+Q)1 or a relaxed (P+Q)2 conformational substate. We did not find the decay component at few hundreds of microseconds time scale indicating that there is no large displacement in the RC structure if QB is present. The diffusion coefficient of the RC/LDAO detergent micelles calculated from the kinetic component was D = 3.8 × 10−11 m2/s that agrees fairly well with the number estimated from the Einstein–Stokes relationship, and relates to a hydrodynamic diameter of 11.4 nm of the RC in LDAO micellar solution. [ABSTRACT FROM AUTHOR]

Abstract: Diorganotin(IV)-complexes of the N-nitroso-N-phenylhydroxylaminates (hereinafter cupf), Et2Sn(cupf)2 (1), Bu2Sn(cupf)2 (2), {[Bu2Sn(cupf)]2O}2 (3), t-Bu2Sn(cupf)2 (4) and Oc2Sn(cupf)2 (5, 6) were prepared and characterised by FT-IR and Mössbauer spectroscopic measurements. The binding modes of the ligand were identified by FT-IR spectroscopy, and it was found that the ligand is coordinated in chelating or bridging mode to the organotin(IV) center. The 119Sn Mössbauer and FT-IR studies support the formation of trans-Oh (1–6) structures. The X-ray diffraction analysis of 4 revealed that the tin centre is in a skew-trapezoidal geometry defined by four donors derived from the cupferronato ligands and two carbon atoms from the tin-bound t butyl substituents. The 119Sn NMR investigations indicate that in solution 4 retains its hexacoordinated nature. [Copyright &y& Elsevier]

Abstract: This review summarized the literature and own data on the parent organotin(IV) compounds and complexes formed with biologically active ligands. [Copyright &y& Elsevier]

Abstract: A number of [Ph3Sn(IV)]+ complexes formed with ligands containing –OH (–Cx2013;COOH group(s) and aromatic {N} donor atom have been prepared. The binding sites of the ligands were identified by FT-IR spectroscopic measurements. In the complexes containing hydroxy and carboxylate functions, the carboxylato group is coordinated to the organotin(IV) centres in monodentate or bridging bidentate manner. It was also found that in the hydroxypyridine and -pyrimidine complexes the [Ph3Sn(IV)]+ moiety in most cases reacts with the phenolic form of the ligands. The rationalisation of the experimental 119Sn Mössbauer nuclear quadrupole splittings, |Δ exp| – according to the point charge model formalism – together with the FT-IR data support the formation of trigonal bipyramidal (Tbp) or octahedral (Oh) molecular structures. Furthermore, X-ray diffraction analysis has been performed on the triphenyltin(IV)-3-phenolato-2(1H)-pyridinone-O,O′ single crystals. The penta-coordinated tin center exhibits a Tbp geometry. In case of 2-picolinic acid, a trans-phenylation was observed during the complexation, resulting [Ph2Sn(IV)]2+ complex and Ph4Sn(IV). [Copyright &y& Elsevier]