Mineralogy of alluvial sediments of Avzyan gold region (the Southern Urals)

The Avzyan gold region is located within the Bashkirian anticlinorium and includes lode gold deposits and placers. The Gorny Priisk, Bogryashka and Ulyuk-Bar gold deposits are hosted in the Riphean metamorphosed carbonaceous sequence. The article describes the mineralogy of the heavy concentrates from alluvial sediments of the streams of Bolshoy Avzyan basin which drains the Gorny Priisk, Bogryashka and Ulyuk-Bar gold ore deposits. The comparison of mineralogical and chemical feature of the studied heavy concentrates is done. Samples and Methods. Samples from the streams were collected every 50-100 m. Hand specimens of ore and host rocks from the lode gold deposits were collected from outcrops and dumps. The content of metals in the heavy concentrates estimated using X-ray fluorescence analyzer Innov-X alfa. Chemical composition of the accessory minerals was studied using electron microscope Vega-3 Tescan with EDA X-Act Oxford. Discussion and Results. The source of the alluvial sediments was the lode gold deposits located in the immediate vicinity of placers. Heavy concentrates of the Kamenny stream are characterized by a high content of As and Cu while ones of the Bogryashka and Bolshoy Klyuch streams show a high content of Cr and Ba. Goethite is major ore mineral for all studied samples. Ilmenite, rutile, epidote and barite are also widespread in the samples from the Bogryashka and Bolshoy Klyuch streams. Native gold is present in the sediments of all studied stream. The greatest number of gold grains was found in the samples from the Bolshoy Klyuch stream. The weak roundness of the golds and the presence of unoxidized sulfides (pyrite, chalcopyrite and pyrrhotite) indicate a relatively small age of placers. Monazite and xenotime morphology suggests autigenic catagenetic and/or metamorphic origin. Monazite contains (apfu) Ce (0.27-0.56), Nd (0.10-0.37) and La (0.09-0.33), minor Pr, Sm, Gd, Eu and Dy; ThO2 up to 9.78 wt. % (0.08 apfu). It is similar with monazite composition from other streams of the east part of the Bashkirian anticlinorium and can be evidence of their similar origin. Xenotime contains major Gd, Dy and Er and minor Tb and Ho. Xenotime from the Bogryashka stream is characterized by the increased concentration of (apfu) Gd (0.10-0.24), Nd (0.01-0.02), Sm (0.03-0.06), Eu (0.02-0.06) and absence of Ho and Yb. Xenotime composition from the Kamenny and Bolshoy Klyuch streams is similar with ones from east part of the Bashkirian anticlinorium. Galena inclusions in REE phosphates, monazite inclusions in goethite and xenotime inclusions in pyrite can be evidence about similar conditions and time of formation gold-sulfide and REE mineralization

Changes in the Ultrastructure of <i>Staphylococcus aureus</i> Cells Make It Possible to Identify and Analyze the Injuring Effects of Ciprofloxacin, Polycationic Amphiphile and Their Hybrid

The purposeful development of synthetic antibacterial compounds requires an understanding of the relationship between effects of compounds and their chemical structure. This knowledge can be obtained by studying changes in bacteria ultrastructure under the action of antibacterial compounds of a certain chemical structure. Our study was aimed at examination of ultrastructural changes in S. aureus cells caused by polycationic amphiphile based on 1,4‒diazabicyclo[2.2.2]octane (DL412), ciprofloxacin and their hybrid (DL5Cip6); the samples were incubated for 15 and 45 min. DL412 first directly interacted with bacterial cell wall, damaging it, then penetrated into the cell and disrupted cytoplasm. Ciprofloxacin penetrated into cell without visually damaging the cell wall, but altered the cell membrane and cytoplasm, and inhibited the division of bacteria. The ultrastructural characteristics of S. aureus cells damaged by the hybrid clearly differed from those under ciprofloxacin or DL412 action. Signs associated with ciprofloxacin predominated in cell damage patterns from the hybrid. We studied the effect of ciprofloxacin, DL412 and their hybrid on S. aureus biofilm morphology using paraffin sections. Clear differences in compound effects on S. aureus biofilm (45 min incubation) were observed. The results obtained allow us to recommend this simple and cheap approach for the initial assessment of antibiofilm properties of synthesized compounds

Extra Purified Exosomes from Human Placenta Contain An Unpredictable Small Number of Different Major Proteins

Exosomes are nanovesicles (30&#8211;100 nm) containing various RNAs and different proteins. Exosomes are important in intracellular communication, immune function, etc. Exosomes from different sources including placenta were mainly obtained by different types of centrifugation and ultracentrifugations and were reported to contain from a few dozen to thousands of different proteins. First crude exosome preparations from four placentas (normal pregnancy) were obtained here using several standard centrifugations but then were additionally purified by gel filtration on Sepharose 4B. Individual preparations demonstrated different gel filtration profiles showing good or bad separation of exosome peaks from two peaks of impurity proteins and their complexes. According to electron microscopy, exosomes before gel filtration contain vesicles of different size, ring-shaped structures forming by ferritin and clusters of aggregated proteins and their complexes. After filtration through 220 nm filters and gel filtration exosomes display typically for exosome morphology and size (30&#8211;100 nm) and do not contain visible protein admixtures. Identification of exosome proteins was carried out by MS and MS/MS MALDI mass spectrometry of proteins&#8217; tryptic hydrolyzates after their SDS-PAGE and 2D electrophoresis. We have obtained unexpected results. Good, purified exosomes contained only 11&#8211;13 different proteins: CD9, CD81, CD-63, hemoglobin subunits, interleukin-1 receptor, annexin A1, annexin A2, annexin A5, cytoplasmic actin, alkaline phosphatase, serotransferin, and probably human serum albumin and immunoglobulins. We assume that a possible number of exosome proteins found previously using crude preparations may be very much overestimated. Our data may be important for study of biological functions of pure exosomes

Generation of three induced pluripotent stem cell lines (RAUi001-A, RAUi001-B and RAUi001-C) from peripheral blood mononuclear cells of a healthy Armenian individual

The study of pathological processes in cells carrying mutations should be carried out in comparison with a healthy control group. Familial Mediterranean fever (FMF), which is caused by a mutation in the MEFV gene, is predominantly found in people of Armenian nationality with the prevalence of 14–100 per 10000. We have obtained induced pluripotent stem cells (iPSCs) from Armenian healthy patient, which will be included as a control group in the study of this disease. iPSCs rapidly proliferate in colonies of cells with a typical pluripotent-like morphology, have a normal karyotype (46,XX). iPSCs express pluripotency markers (OCT4, SOX2, TRA-1–60, NANOG) and are able to give derivatives of three germ layers

3-Arylidene-2-oxindoles as Potent NRH:Quinone Oxidoreductase 2 Inhibitors

The enzyme NRH:quinone oxidoreductase 2 (NQO2) plays an important role in the pathogenesis of various diseases such as neurodegenerative disorders, malaria, glaucoma, COVID-19 and cancer. NQO2 expression is known to be increased in some cancer cell lines. Since 3-arylidene-2-oxindoles are widely used in the design of new anticancer drugs, such as kinase inhibitors, it was interesting to study whether such structures have additional activity towards NQO2. Herein, we report the synthesis and study of 3-arylidene-2-oxindoles as novel NRH:quinone oxidoreductase inhibitors. It was demonstrated that oxindoles with 6-membered aryls in the arylidene moiety were obtained predominantly as E-isomers while for some 5-membered aryls, the Z-isomers prevailed. The most active compounds inhibited NQO2 with an IC50 of 0.368 &micro;M. The presence of a double bond in the oxindoles was crucial for NQO2 inhibition activity. There was no correlation between NQO2 inhibition activity of the synthesized compounds and their cytotoxic effect on the A549 cell line

3-Arylidene-2-oxindoles as Potent NRH:Quinone Oxidoreductase 2 Inhibitors

The enzyme NRH:quinone oxidoreductase 2 (NQO2) plays an important role in the pathogenesis of various diseases such as neurodegenerative disorders, malaria, glaucoma, COVID-19 and cancer. NQO2 expression is known to be increased in some cancer cell lines. Since 3-arylidene-2-oxindoles are widely used in the design of new anticancer drugs, such as kinase inhibitors, it was interesting to study whether such structures have additional activity towards NQO2. Herein, we report the synthesis and study of 3-arylidene-2-oxindoles as novel NRH:quinone oxidoreductase inhibitors. It was demonstrated that oxindoles with 6-membered aryls in the arylidene moiety were obtained predominantly as E-isomers while for some 5-membered aryls, the Z-isomers prevailed. The most active compounds inhibited NQO2 with an IC50 of 0.368 µM. The presence of a double bond in the oxindoles was crucial for NQO2 inhibition activity. There was no correlation between NQO2 inhibition activity of the synthesized compounds and their cytotoxic effect on the A549 cell line

Design, Synthesis, and Cancer Cell Growth Inhibitory Activity of Triphenylphosphonium Derivatives of the Triterpenoid Betulin

A series of new triphenylphosphonium (TPP) derivatives of the triterpenoid betulin (<b>1</b>, 3-lup-20(29)-ene-3β,28-diol) have been synthesized and evaluated for cytotoxic effects against human breast cancer (MCF-7), prostate adenocarcinoma (PC-3), vinblastine-resistant human breast cancer (MCF-7/Vinb), and human skin fibroblast (HSF) cells. The TPP moiety was applied as a carrier group through the acyl linker at the 28- or 3- and 28-positions of betulin to promote cellular and mitochondrial accumulation of the resultant compounds. A structure–activity relationship study has revealed the essential role of the TPP group in the biological properties of the betulin derivatives produced. The present results showed that a conjugate of betulin with TPP (<b>3</b>) enhanced antiproliferative activity toward vinblastine-resistant MCF-7 cells, with an IC₅₀ value as low as 0.045 μM

Ultrastructural Abnormalities in Induced Pluripotent Stem Cell-Derived Neural Stem Cells and Neurons of Two Cohen Syndrome Patients

Cohen syndrome is an autosomal recessive disorder caused by VPS13B (COH1) gene mutations. This syndrome is significantly underdiagnosed and is characterized by intellectual disability, microcephaly, autistic symptoms, hypotension, myopia, retinal dystrophy, neutropenia, and obesity. VPS13B regulates intracellular membrane transport and supports the Golgi apparatus structure, which is critical for neuron formation. We generated induced pluripotent stem cells from two patients with pronounced manifestations of Cohen syndrome and differentiated them into neural stem cells and neurons. Using transmission electron microscopy, we documented multiple new ultrastructural changes associated with Cohen syndrome in the neuronal cells. We discovered considerable disturbances in the structure of some organelles: Golgi apparatus fragmentation and swelling, endoplasmic reticulum structural reorganization, mitochondrial defects, and the accumulation of large autophagosomes with undigested contents. These abnormalities underline the ultrastructural similarity of Cohen syndrome to many neurodegenerative diseases. The cell models that we developed based on patient-specific induced pluripotent stem cells can serve to uncover not only neurodegenerative processes, but the causes of intellectual disability in general

Findings supporting flagellation of “<i>Ca</i>. Nitrosotenuis uzonensis”

<p>(A) Intact cell stained with uranyl acetate, showing a subpolar tail-like cell projection, possibly a flagellum, and a network of hexagonal structures on the cell surface. (B) Organization of flagellar- and chemotaxis-associated genes in its genome. Genes encoding parts of the archaeal flagellum (<i>fla</i> genes) and chemotaxis apparatus (<i>che</i> genes) are given in red and green, respectively, whereas other genes are shown in grey. For details on these genes please refer to Table S8 in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0080835#pone.0080835.s004" target="_blank">File S1</a>. Black double bars indicate separate genomic regions, while blue bars display contig ends. MCP, putative methyl-accepting chemotaxis protein.</p

Near-stoichiometric oxidation of ammonia and production of nitrite by culture N4 over 15 days.

<p>Two replicate culture flasks (indicated by red and green symbols) were inoculated with 10 vol% of the parent culture, leading to an initial nitrite concentration of ~0.5 mM. Nitrate was not detectable during the whole experiment. Axis scaling is identical for the ammonia (triangles) and nitrite (squares) concentrations.</p