Effect of high glucose concentration on the synthesis of monocyte chemoattractant protein-1 in human peritoneal mesothelial cells: Involvement of protein kinase C

Human peritoneal mesothelial cells (HMC) contribute to the activation and control of inflammatory processes in the peritoneum by their potential to produce various inflammatory mediators. The present study was designed to assess the effect of glucose, the osmotic active compound in most commercially available peritoneal dialysis fluids, on the synthesis of the C-C chemokine monocyte chemoattractant protein-1 (MCP-1) in cultured HMC. The MCP-1 concentration in the cell supernatants was determined by enzyme-linked immunosorbent assay and the MCP-1 mRNA expression was examined using Northern blot analysis. Incubation of HMC with glucose (30-120 mM) resulted in a time- and concentration-dependent increase in MCP-1 protein secretion and mRNA expression. After 24 h the MCP-1 synthesis was increased from 2.8 +/- 0.46 to 4.2 +/- 0.32 ng/10(5) cells (n = 5, p 2001 S. Karger AG. Basel

c-axis Josephson Tunneling in Twinned YBCO Crystals

Josephson tunneling between YBCO and Pb with the current flowing along the c-axis of the YBCO is persumed to come from an s-wave component of the superconductivity of the YBCO. Experiments on multi-twin samples are not entirely consistent with this hypothesis. The sign change of the s-wave order parameter across the N_T twin boundaries should give cancelations, resulting in a small $(\sqrt{N})$ tunneling current. The actual current is larger than this. We present a theory of this unexpectedly large current based upon a surface effect: disorder-induced supression of the d-wave component at the (001) surface leads to s-wave coherence across the twin boundaries and a non-random tunneling current. We solve the case of an ordered array of d+s and d-s twins, and estimate that the twin size at which s-wave surface coherence occurs is consistent with typical sizes observed in experiments. In this picture, there is a phase difference of $\pi/2$ between different surfaces of the material. We propose a corner junction experiment to test this picture.Comment: 5 pages, 4 eps figure

Electron beam driven alkali metal atom source for loading a magneto-optical trap in a cryogenic environment

We present a versatile and compact electron beam driven source for alkali metal atoms, which can be implemented in cryostats. With a heat load of less than 10mW, the heat dissipation normalized to the atoms loaded into the magneto-optical Trap (MOT), is about a factor 1000 smaller than for a typical alkali metal dispenser. The measured linear scaling of the MOT loading rate with electron current observed in the experiments, indicates that electron stimulated desorption is the corresponding mechanism to release the atoms.Comment: 5 pages, 3 figure

Testing spontaneous localization theories with matter-wave interferometry

We propose to test the theory of continuous spontaneous localization (CSL) in an all-optical time-domain Talbot-Lau interferometer for clusters with masses exceeding 1000000 amu. By assessing the relevant environmental decoherence mechanisms, as well as the growing size of the particles relative to the grating fringes, we argue that it will be feasible to test the quantum superposition principle in a mass range excluded by recent estimates of the CSL effect.Comment: 4 pages, 3 figures; corresponds to published versio

Genome sequencing and molecular networking analysis of the wild fungusAnthostomella pineareveal its ability to produce a diverse range of secondary metabolites

Background Filamentous fungi are prolific producers of bioactive molecules and enzymes with important applications in industry. Yet, the vast majority of fungal species remain undiscovered or uncharacterized. Here we focus our attention to a wild fungal isolate that we identified as Anthostomella pinea. The fungus belongs to a complex polyphyletic genus in the family of Xylariaceae, which is known to comprise endophytic and pathogenic fungi that produce a plethora of interesting secondary metabolites. Despite that, Anthostomella is largely understudied and only two species have been fully sequenced and characterized at a genomic level.Results In this work, we used long-read sequencing to obtain the complete 53.7 Mb genome sequence including the full mitochondrial DNA. We performed extensive structural and functional annotation of coding sequences, including genes encoding enzymes with potential applications in biotechnology. Among others, we found that the genome of A. pinea encodes 91 biosynthetic gene clusters, more than 600 CAZymes, and 164 P450s. Furthermore, untargeted metabolomics and molecular networking analysis of the cultivation extracts revealed a rich secondary metabolism, and in particular an abundance of sesquiterpenoids and sesquiterpene lactones. We also identified the polyketide antibiotic xanthoepocin, to which we attribute the anti–Gram-positive effect of the extracts that we observed in antibacterial plate assays.Conclusions Taken together, our results provide a first glimpse into the potential of Anthstomella pinea to provide new bioactive molecules and biocatalysts and will facilitate future research into these valuable metabolites

Transcriptomic signatures of neuronal differentiation and their association with risk genes for autism spectrum and related neuropsychiatric disorders.

Genes for autism spectrum disorders (ASDs) are also implicated in fragile X syndrome (FXS), intellectual disabilities (ID) or schizophrenia (SCZ), and converge on neuronal function and differentiation. The SH-SY5Y neuroblastoma cell line, the most widely used system to study neurodevelopment, is currently discussed for its applicability to model cortical development. We implemented an optimal neuronal differentiation protocol of this system and evaluated neurodevelopment at the transcriptomic level using the CoNTeXT framework, a machine-learning algorithm based on human post-mortem brain data estimating developmental stage and regional identity of transcriptomic signatures. Our improved model in contrast to currently used SH-SY5Y models does capture early neurodevelopmental processes with high fidelity. We applied regression modelling, dynamic time warping analysis, parallel independent component analysis and weighted gene co-expression network analysis to identify activated gene sets and networks. Finally, we tested and compared these sets for enrichment of risk genes for neuropsychiatric disorders. We confirm a significant overlap of genes implicated in ASD with FXS, ID and SCZ. However, counterintuitive to this observation, we report that risk genes affect pathways specific for each disorder during early neurodevelopment. Genes implicated in ASD, ID, FXS and SCZ were enriched among the positive regulators, but only ID-implicated genes were also negative regulators of neuronal differentiation. ASD and ID genes were involved in dendritic branching modules, but only ASD risk genes were implicated in histone modification or axonal guidance. Only ID genes were over-represented among cell cycle modules. We conclude that the underlying signatures are disorder-specific and that the shared genetic architecture results in overlaps across disorders such as ID in ASD. Thus, adding developmental network context to genetic analyses will aid differentiating the pathophysiology of neuropsychiatric disorders

Structural characterization and extended substrate scope analysis of two Mg<sup>2+</sup>-dependent O-methyltransferases from bacteria

Oxygen-directed methylation is a ubiquitous tailoring reaction in natural product pathways catalysed by O-methyltransferases (OMTs). Promiscuous OMT biocatalysts are thus a valuable asset in the toolkit for sustainable synthesis and optimization of known bioactive scaffolds for drug development. Here, we characterized two bacterial OMTs from Desulforomonas acetoxidans and Streptomyces avermitilis in terms of their enzymatic properties and substrate scope and determined their crystal structures. Both OMTs methylated a wide range of catechol-like substrates, including flavonoids, coumarins, hydroxybenzoic acids and their respective aldehydes, an anthraquinone and an indole. One enzyme also accepted a steroid. The product range included pharmaceutically relevant compounds such as (iso)fraxidin, iso(scopoletin), chrysoeriol, alizarin 1-methyl ether and 2-methoxyestradiol. Interestingly, certain non-catechol flavonoids and hydroxybenzoic acids were also methylated. This study expands the knowledge on substrate preference and structural diversity of bacterial catechol OMTs and paves the way for their use in (combinatorial) pathway engineering.Table of contents Two promiscuous O-methyltransferases from bacteria were found to methylate a panel of catechol substrates towards high-value medicinal compounds. Surprisingly, the non-catechol substrates 5-hydroxyflavonoids and o-hydroxybenzoic acids/aldehydes were also methylated at low conversion rates. The crystal structures reveal potential target sites for enzyme engineering for biocatalytic applications.Competing Interest StatementThe authors have declared no competing interest

Structural Characterization and Extended Substrate Scope Analysis of Two Mg²⁺-Dependent O-Methyltransferases from Bacteria**

Oxygen-directed methylation is a ubiquitous tailoring reaction in natural product pathways catalysed by O-methyltransferases (OMTs). Promiscuous OMT biocatalysts are thus a valuable asset in the toolkit for sustainable synthesis and optimization of known bioactive scaffolds for drug development. Here, we characterized the enzymatic properties and substrate scope of two bacterial OMTs from Desulforomonas acetoxidans and Streptomyces avermitilis and determined their crystal structures. Both OMTs methylated a wide range of catechol-like substrates, including flavonoids, coumarins, hydroxybenzoic acids, and their respective aldehydes, an anthraquinone and an indole. One enzyme also accepted a steroid. The product range included pharmaceutically relevant compounds such as (iso)fraxidin, iso(scopoletin), chrysoeriol, alizarin 1-methyl ether, and 2-methoxyestradiol. Interestingly, certain non-catechol flavonoids and hydroxybenzoic acids were also methylated. This study expands the knowledge on substrate preference and structural diversity of bacterial catechol OMTs and paves the way for their use in (combinatorial) pathway engineering.</p

Observation of the second harmonic in superconducting current-phase relation of Nb/Au/(001)YBa2Cu3Ox heterojunctions

The superconducting current-phase relation (CPR) of Nb/Au/(001)YBa2Cu3Ox heterojunctions prepared on epitaxial c-axis oriented YBa2Cu3Ox thin films has been measured in a single-junction interferometer. For the first time, the second harmonic of the CPR of such junctions has been observed. The appearance of the second harmonic and the relative sign of the first and second harmonics of the CPR can be explained assuming, that the macroscopic pairing symmetry of our YBa2Cu3Ox thin films is of the d+s typeComment: 11 pages, 4 figure