In situ scanning tunneling microscopy (STM), atomic force microscopy (AFM) and quartz crystal microbalance (EQCM) studies of the electrochemical deposition of tantalum in two different ionic liquids with the 1-butyl-1-methylpyrrolidinium cation

The electrochemical reduction of 0.1 M TaF₅ in two hydrophobic ionic liquids (1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl) trifluorophosphate ([Py_1,4]FAP) and 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl) amide ([Py_1,4]TFSA) is probed using three <i>in situ</i> techniques: scanning tunneling microscopy (STM), atomic force microscopy (AFM), and electrochemical quartz crystal microbalance (EQCM). These techniques reveal that under similar conditions TaF₅is more easily reduced in the liquids with [TFSA]⁻ than [FAP]⁻anions. Increasing the temperature reduced the viscosity and density of the ionic liquids which facilitates TaF₅ electroreduction, in particular, in [Py_1,4]TFSA. A herringbone reconstruction of the Au electrode was observed by STM for both ionic liquids with and without TaF₅. Ta deposition was proved by STM and EQCM in [Py_1,4]TFSA. Cracked layers, with ionic liquid trapped inside, were obtained by direct plating from the [TFSA]− ionic liquid. No Ta containing deposits could be obtained in the liquid with the [FAP]− anion

A specific class of infectious agents isolated from bovine serum and dairy products and peritumoral colon cancer tissue

ABSTRACTThe in silico analyses of 109 replication-competent genomic DNA sequences isolated from cow milk and its products (97 in the bovine meat and milk factors 2 group – BMMF2, and additional 4 in BMMF1) seems to place these in a specific class of infectious agents spanning between bacterial plasmid and circular ssDNA viruses. Satellite-type small plasmids with partial homology to larger genomes, were also isolated in both groups. A member of the BMMF1 group H1MBS.1 was recovered in a distinctly modified form from colon tissue by laser microdissection. Although the evolutionary origin is unknown, it draws the attention to the existence of a hitherto unrecognized, broad spectrum of potential pathogens. Indirect hints to the origin and structure of our isolates, as well as to their replicative behaviour, result from parallels drawn to the Hepatitis deltavirus genome structure and replication

Stereochemical Consequences of Oxygen Atom Transfer and Electron Transfer in Imido/Oxido Molybdenum(IV, V, VI) Complexes with Two Unsymmetric Bidentate Ligands

Two equivalents of the unsymmetrical Schiff base ligand <b>(L</b>^{<i><b>t</b></i><b>Bu</b>}<b>)</b>^<b>–</b> (4-<i>tert</i>-butyl phenyl­(pyrrolato-2-ylmethylene)­amine) and MoCl₂(N<i>t</i>Bu)­O­(dme) (dme = 1,2-dimethoxyethane) gave a single stereoisomer of a mixed imido/oxido Mo^VI complex <b>2</b>^{<i><b>t</b></i><b>Bu</b>}. The stereochemistry of <b>2</b>^{<i><b>t</b></i><b>Bu</b>} was elucidated using X-ray diffraction, NMR spectroscopy, and DFT calculations. The complex is active in an oxygen atom transfer (OAT) reaction to trimethyl phosphane. The putative intermediate five-coordinate Mo^IV imido complex coordinates a PMe₃ ligand, giving the six-coordinate imido phosphane Mo^IV complex <b>5</b>^{<i><b>t</b></i><b>Bu</b>}. The stereochemistry of <b>5</b>^{<i><b>t</b></i><b>Bu</b>} is different from that of <b>2</b>^{<i><b>t</b></i><b>Bu</b>} as shown by NMR spectroscopy, DFT calculations, and X-ray diffraction. Single-electron oxidation of <b>5</b>^{<i><b>t</b></i><b>Bu</b>} with ferrocenium hexafluorophosphate gave the stable cationic imido phosphane Mo^V complex <b>[5</b>^{<i><b>t</b></i><b>Bu</b>}<b>]</b>^<b>+</b> as the PF₆^– salt. EPR spectra of <b>[5</b>^{<i><b>t</b></i><b>Bu</b>}<b>]­(PF</b>_<b>6</b><b>)</b> confirmed the presence of PMe₃ in the coordination sphere. Single-crystal X-ray diffraction analysis of <b>[5</b>^{<i><b>t</b></i><b>Bu</b>}<b>]­(PF</b>_<b>6</b><b>)</b> revealed that electron transfer occurred under retention of the stereochemical configuration. The rate of OAT, the outcome of the electron transfer reaction, and the stabilities of the imido complexes presented here differ dramatically from those of analogous oxido complexes

The need for digitalisation in electroplating – How digital approaches can help to optimize the electrodeposition of chromium from trivalent electrolytes

In order to make material design processes more efficient in the future, the underlying multidimensional process parameter spaces must be systematically explored using digitalisation techniques such as machine learning (ML) and digital simulation. In this paper we shortly review essential concepts for the digitalisation of electrodeposition processes with a special focus on chromium plating from trivalent electrolytes

Analysis of chronic inflammatory lesions of the colon for BMMF Rep antigen expression and CD68 macrophage interactions

Consumption of Eurasian bovine meat and milk has been associated with cancer development, in particular with colorectal cancer (CRC). In addition, zoonotic infectious agents from bovine products were proposed to cause colon cancer (zur Hausen et al., 2009). Bovine meat and milk factors (BMMF) are small episomal DNA molecules frequently isolated from bovine sera and milk products, and recently, also from colon cancer (de Villiers et al., 2019). BMMF are bioactive in human cells and were proposed to induce chronic inflammation in precancerous tissue leading to increased radical formation: for example, reactive oxygen and reactive nitrogen species and elevated levels of DNA mutations in replicating cells, such as cancer progenitor cells (zur Hausen et al., 2018). Mouse monoclonal antibodies against the replication (Rep) protein of H1MSB.1 (BMMF1) were used to analyze BMMF presence in different cohorts of CRC peritumor and tumor tissues and cancer-free individuals by immunohistochemistry and Western blot. BMMF DNA was isolated by laser microdissection from immunohistochemistry-positive tissue regions. We found BMMF Rep protein present specifically in close vicinity of CD68$^{+}$ macrophages in the interstitial lamina propria adjacent to CRC tissues, suggesting the presence of local chronic inflammation. BMMF1 (modified H1MSB.1) DNA was isolated from the same tissue regions. Rep and CD68$^{+}$ detection increased significantly in peritumor cancer tissues when compared to tissues of cancer-free individuals. This strengthens previous postulations that BMMF function as indirect carcinogens by inducing chronic inflammation and DNA damage in replicating cells, which represent progress to progenitor cells for adenoma (polyps) formation and cancer

Copper Uptake Induces Self-Assembly of 18.5 kDa Myelin Basic Protein (MBP)

Myelin basic protein (MBP) is predominantly found in the membranes of the myelin sheath of the central nervous system and is involved in important protein-protein and protein-lipid interactions in vivo and in vitro. Furthermore, divalent transition metal ions, especially Zn2+ and Cu2+, seem to directly affect the MBP-mediated formation and stabilization of the myelin sheath of the central nervous system. MBP belongs to the realm of intrinsically disordered proteins, and only fragmentary information is available regarding its partial structure(s) or supramolecular arrangements. Here, using standard continuous wave and modern pulse electron paramagnetic resonance methods, as well as dynamic light scattering, we demonstrate the uptake and specific coordination of two Cu2+ atoms or one Zn2+ atom per MBP molecule in solution. In the presence of phosphates, further addition of divalent metal ions above a characteristic threshold of four Cu2+ atoms or two Zn2+ atoms per MBP molecule leads to the formation of large MBP aggregates within the protein solution. In vivo, MBP-MBP interactions may thus be mediated by divalent cations