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The work presents results of the in vitro and in silico study of formation of amyloid-like structures under harsh denaturing conditions by non-specific OmpF porin of Yersinia pseudotuberculosis (YpOmpF), a membrane protein with β-barrel conformation. It has been shown that in order to obtain amyloid-like porin aggregates, preliminary destabilization of its structure in a buffer solution with acidic pH at elevated temperature followed by long-term incubation at room temperature is necessary. After heating at 95°C in a solution with pH 4.5, significant conformational rearrangements are observed in the porin molecule at the level of tertiary and secondary structure of the protein, which are accompanied by the increase in the content of total β-structure and sharp decrease in the value of characteristic viscosity of the protein solution. Subsequent long-term exposure of the resulting unstable intermediate YpOmpF at room temperature leads to formation of porin aggregates of various shapes and sizes that bind thioflavin T, a specific fluorescent dye for the detection of amyloid-like protein structures. Compared to the initial protein, early intermediates of the amyloidogenic porin pathway, oligomers, have been shown to have increased toxicity to the Neuro-2aCCL-131™ mouse neuroblastoma cells. The results of computer modeling and analysis of the changes in intrinsic fluorescence during protein aggregation suggest that during formation of amyloid-like aggregates, changes in the structure of YpOmpF affect not only the areas with an internally disordered structure corresponding to the external loops of the porin, but also main framework of the molecule, which has a rigid spatial structure inherent to β-barrel. [ABSTRACT FROM AUTHOR]

Information about potential earthquake sources is a key issue for seismic hazard assessment. This study presents the application of a phenomenological approach based on pattern recognition to determine the possible locations of strong earthquakes in the Bulgarian region. The technique assumes the origin of strong earthquakes in morphostructural nodes formed around the intersections of morphostructural lineaments identified by morphostructural zoning. For the territory of the Bulgaria and neighbouring regions, 178 nodes were defined in this work. The CORA-3 pattern recognition algorithm identified 59 seismogenic nodes analysing a set of geophysical and geological node's characteristics. The identified seismogenic nodes are capable to generate earthquakes with magnitude equal to or greater than 6 and are located at the boundaries between the largest tectonic domains: Rila, Pirin, and Rhodope orogens; the Serbian-Macedonian massif; and in the Stara Planina belt. The set of characteristic features of seismogenic nodes indicates that the vicinity of potential nodes is characterized by a high contrast of neotectonic movements of the Earth's crust and the presence of deep heterogeneities in the Earth's crust. About 40% of the recognized nodes are not associated with any earthquakes, while the rest of the recognized seismogenic nodes are characterized by an area with a radius of 25 km where earthquakes are known to occur. Part of these "non active" seismogenic nodes are close to the historical events with magnitudes higher than 5.5 since the magnitude and location of historical events have large uncertainties. Another part of the seismogenic nodes may slightly change the location due to the uncertainties in morphostructural zonation. Other nodes may indicate unknown historical seismicity or paleoearthquakes. Defined M6+ seismogenic nodes can fill the potential gaps in the recorded seismicity on the territory of Bulgaria, thus to improve the seismic hazard assessment of the studied region. [ABSTRACT FROM AUTHOR]

The relevance of this study is due to the specifics of the subculture global context, supplemented by a semantic paradigm determined by the linguistic and cultural traditions and the social and cultural background of the Russian language community. The study aims to identify the perception of proper names in rap texts, their axiological understanding as cultural dominants that make up the individual cognitive base. Based on the conducted research, the proper name property to act as metaphorical intertextual signs of conceptualization and categorization of the real world, inherent for rap discourse, has been established. [ABSTRACT FROM AUTHOR]

Our objectives were to (1) compare different regimens of hormonal therapy (HT) in young women with atypical endometrial hyperplasia (AEH) and early endometrial cancer (EC), (2) assess reproductive and oncologic outcomes and (3) explore possible predictors of complete response (CR) and disease free survival (DFS). Reproductive age women with AEH and Grade 1–2 endometrioid EC with no or minimal myometrial invasion on MRI treated with different regimens of HT were prospectively analyzed. Treatment protocols included levonorgestrel intrauterine device (LNG IUD), gonadotropin-releasing hormone agonist (aGnRH) or high-dose oral medroxyprogesteron acetate (MPA) separately and in combinations. Total of 418 patients with AEH (n = 228) and EC (n = 190) aged 19–46 years received HT. Overall CR rate was 96% in AEH and 88% in EC patients (р < 0.001). None of the regimens used in AEH (LNG IUD + 2 D&C vs. LNG IUD + aGnRH vs. LNG IUD + 3 D&C) was found inferior to the others (CR of 98%, 95%, 100%, respectively, p > 0.05) except for MPA alone (CR 87%, р = 0.009). Out of four HT regimens used in EC LNG IUD + aGnRH+3 D&C was superior to all others (CR 96%, р = 0.026) where 2 D&Cs were performed or oral MPA was prescribed. The median follow-up for 339 patients was 33 months (range: 3–136), 68% of patients (n = 232) attempted conception, 38% (n = 89) of them used ART. The birth rate was 42% (n = 97). The rate of recurrence was 26% (50/196) in AEH group and 36% (51/143) in EC group (p = 0.05). Birth after treatment (HR = 0.24) or LNG IUD maintenance (HR = 0.18) were associated with superior DFS (p < 0.001 for both). ART use did not influence DFS. Hormonal therapy of AEH and early EC with LNG IUD is superior to MPA-containing regimens, however still carries high risk of recurrence. Post-treatment pregnancy rates are satisfactory and can be further improved by broader ART use which was proven safe. Initial diagnosis of AEH, post-treatment child birth and LNG IUD maintenance were associated with decreased rates of recurrence. • The largest study on fertility-sparing treatment of atypical hyperplasia and early endometrial cancer. • Eight treatment regimens have been studied and compared. • Predictors of response to treatment and recurrences have been identified. • In lieu of proven ART safety after treatment, reproductive results can be improved with broader use of IVF. [ABSTRACT FROM AUTHOR]

The connective tissue components that form the atherosclerotic plaque body are produced by the plaque inner mass cells (PIMC), located inside the plaque. We report an approach to isolate and culture cells from the connective tissue of stable and vulnerable human atherosclerotic plaques based on elimination of non-connective tissue cells such as blood and non-plaque intima cells with a lysis buffer. The resulting plaque cells were characterized by growth capacity, morphology, transcriptome profiling and specific protein expression. Plaque cells slowly proliferated for up to three passages unaffected by the use of proliferation stimulants or changes of culture media composition. Stable plaques yielded more cells than vulnerable ones. Plaque cell cultures also contained several morphological cellular types. RNA-seq profiles of plaque cells were different from any of the cell types known to be involved in atherogenesis. The expression of the following proteins was observed in cultured plaque cells: smooth muscle cells marker α-SMA, macrophage marker CD14, extracellular matrix proteins aggrecan, fibronectin, neovascularisation markers VEGF-A, CD105, cellular adhesion receptor CD31 and progenitor/dedifferentiation receptor CD34. Differential expression of several notable transcripts in cells from stable and vulnerable plaques suggests the value of plaque cell culture studies for the search of plaque vulnerability markers. [ABSTRACT FROM AUTHOR]

The article considers the conceptual basis for strengthening social and labor potential of sustainable development in the context of economic efficiency and social justice. The essence of the categories social potential, social capital and social imperative in their interrelation with the social and labor sphere of society with the account of the needs of sustainable development is specified. Strengthening of social potential is considered as a complex of actions in such areas as education, culture, health care, economic and social spheres, social relations. The paper focuses on strong interconnections work - employment - labor potential - social potential - human development - sustainable development. A mechanism of strengthening social and labor potential through the transformation of employment in the context of the paradigm of sustainable development is suggested. [ABSTRACT FROM AUTHOR]

Background: Inteins are mobile, self-splicing sequences that interrupt proteins and occur across all three domains of life. Scrutiny of the intein landscape in prokaryotes led to the hypothesis that some inteins are functionally important. Our focus shifts to eukaryotic inteins to assess their diversity, distribution, and dissemination, with the aim to comprehensively evaluate the eukaryotic intein landscape, understand intein maintenance, and dissect evolutionary relationships. Results: This bioinformatics study reveals that eukaryotic inteins are scarce, but present in nuclear genomes of fungi, chloroplast genomes of algae, and within some eukaryotic viruses. There is a preponderance of inteins in several fungal pathogens of humans and plants. Inteins are pervasive in certain proteins, including the nuclear RNA splicing factor, Prp8, and the chloroplast DNA helicase, DnaB. We find that eukaryotic inteins frequently localize to unstructured loops of the host protein, often at highly conserved sites. More broadly, a sequence similarity network analysis of all eukaryotic inteins uncovered several routes of intein mobility. Some eukaryotic inteins appear to have been acquired through horizontal transfer with dsDNA viruses, yet other inteins are spread through intragenomic transfer. Remarkably, endosymbiosis can explain patterns of DnaB intein inheritance across several algal phyla, a novel mechanism for intein acquisition and distribution. Conclusions: Overall, an intriguing picture emerges for how the eukaryotic intein landscape arose, with many evolutionary forces having contributed to its current state. Our collective results provide a framework for exploring inteins as novel regulatory elements and innovative drug targets. [ABSTRACT FROM AUTHOR]

People are intent to make similar choices especially in consumer goods markets. To address both explanations of this persistence, i.e. state dependence and heterogeneity in preferences, we use random coefficient logit model based on scanner panel data on juice purchases. The product differentiation of the chosen category allows us to model three dimensions of state dependence on brand, size and flavor characteristics. We provide evidence that the persistence in brand choices is positively correlated with persistence in size and flavor choices, thus the consumer pattern is prone to be inertial or variety seeking in every product characteristics. Simultaneously we show that the more sensitive to price and promotional activities consumers are, the less inertial is their behavior. [ABSTRACT FROM AUTHOR]

The duality of group II introns, capable of carrying out both self-splicing and retromobility reactions, is hypothesized to have played a profound role in the evolution of eukaryotes. These introns likely provided the framework for the emergence of eukaryotic retroelements, spliceosomal introns and other key components of the spliceosome. Group II introns are found in all three domains of life and are therefore considered to be exceptionally successful mobile genetic elements. Initially identified in organellar genomes, group II introns are found in bacteria, chloroplasts, and mitochondria of plants and fungi, but not in nuclear genomes. Although there is no doubt that prokaryotic and organellar group II introns are evolutionary related, there are remarkable differences in survival strategies between them. Furthermore, an evolutionary relationship of group II introns to eukaryotic retroelements, including telomeres, and spliceosomes is unmistakable. [ABSTRACT FROM AUTHOR]

Mobile genetic elements either encode their own mobilization machineries or hijack them from other mobile elements. Multiple classes of mobile elements often coexist within genomes and it is unclear whether they have the capacity to functionally interact and even collaborate. We investigate the possibility that molecular machineries of disparate mobile elements may functionally interact, using the example of a retrotransposon, in the form of a mobile group II intron, found on a conjugative plasmid pRS01 in Lactococcus lactis. This intron resides within the pRS01 ltrB gene encoding relaxase, the enzyme required for nicking the transfer origin (oriT) for conjugal transmission of the plasmid into a recipient cell. Here, we show that relaxase stimulates both the frequency and diversity of retrotransposition events using a retromobility indicator gene (RIG), and by developing a high-throughput genomic retrotransposition detection system called RIG-Seq. We demonstrate that LtrB relaxase not only nicks ssDNA of its cognate oriT in a sequence- and strand-specific manner, but also possesses weak off-target activity. Together, the data support a model in which the two different mobile elements, one using an RNA-based mechanism, the other using DNA-based transfer, do functionally interact. Intron splicing facilitates relaxase expression required for conjugation, whereas relaxase introduces spurious nicks in recipient DNA that stimulate both the frequency of intron mobility and the density of events. We hypothesize that this functional interaction between the mobile elements would promote horizontal conjugal gene transfer while stimulating intron dissemination in the donor and recipient cells. [ABSTRACT FROM AUTHOR]

Marinomonas primoryensis KMM 3633T, extreme living marine bacterium was isolated from a sample of coastal sea ice in the Amursky Bay near Vladivostok, Russia. The goal of our investigation is to study outer membrane channels determining cell permeability. Porin from M. primoryensis KMM 3633T (MpOmp) has been isolated and characterized. Amino acid analysis and whole genome sequencing were the sources of amino acid data of porin, identified as Porin_4 according to the conservative domain searching. The amino acid composition of MpOmp distinguished by high content of acidic amino acids and low content of sulfur-containing amino acids, but there are no tryptophan residues in its molecule. The native MpOmp existed as a trimer. The reconstitution of MpOmp into black lipid membranes demonstrated its ability to form ion channels whose conductivity depends on the electrolyte concentration. The spatial structure of MpOmp had features typical for the classical gram-negative porins. However, the oligomeric structure of isolated MpOmp was distinguished by very low stability: heat-modified monomer was already observed at 30 °C. The data obtained suggest the stabilizing role of lipids in the natural membrane of marine bacteria in the formation of the oligomeric structure of porin. [ABSTRACT FROM AUTHOR]

The rheological, mechanical, and electrical properties and structure of rods and wires made of aluminum alloy concentration of 1% REM (0.6% Ce and 0.4% La) are investigated and presented. The rods were produced by combined rolling-extrusion (CRE) from two different types of billets: casting into a mold 14×14 mm and into electromagnetic mold (EMM) Ø12.5 mm. A database of the DEFORM 3D complex was created for computer modeling of the CRE process. The tensile strength of rods Ø9 and 5 mm obtained using CRE method is 120–140 MPa and elongation to failure is 15–26% for billets from EMM. For billets 14×14 mm, the ultimate tensile strength is 112–125 MPa, which is comparatively lower than that of rods made from round billets (elongation to failure is 26–34%). The plastic properties of the final wire Ø2 mm from a round billet after EMM are higher than wire Ø2 mm from a billet obtained by casting into a mold 14×14 mm. Rods after CRE from both types of billets are characterized by fairly high ductility. To obtain Ø2-mm wire from rods, no intermediate annealing was required. The values of electrical resistance are taken from 0.02271 to 0.0301 Ω‧mm2/m for rods from 12.5-mm billets and from 0.02776 to 0.03413 Ω‧mm2/m for rods from billets 14×14 mm. The electrical resistance values for wire Ø2 mm from billets 14×14 mm are higher than for wire obtained from rods after EMM. Microstructure shows that the final wire after CRE from billet in EMM has a more extensive structure than after CRE from billets with dimensions of 14×14 mm. [ABSTRACT FROM AUTHOR]

Abstract: The convenient synthesis of new functionalized organophosphorus acids and their derivatives containing indan moieties was developed. The regioselective radical addition of bis(trimethylsiloxy)phosphine to indene proceeds to give rise to 2‐indanylphosphonite as key compound for preparation of above acids with bicyclic substituents. Azobis(isobutyronitrile) (AIBN) in the conditions of its thermolysis was used as effective initiator of the addition reaction. The further treatment of organophosphorus acids trimethylsilyl esters with the methanolic sodium methoxide solution resulted in the water‐soluble sodium salts of the corresponding acids. [ABSTRACT FROM AUTHOR]

Abstract: The convenient syntheses of new organophosphorus‐substituted benzofulvenes with indenyl moieties from bis(trimethylsilyl) inden‐2‐ylphosphonate and substituted azomethines in the presence of the effective initiator‐sodium hydride are developed. The following treatment of phosphonates with methanolic sodium methylate gives stable water‐soluble disodium salts of corresponding phosphonic acids. [ABSTRACT FROM AUTHOR]

The addition of trimethylsilyl esters of trivalent phosphorus acids to trimethylsilyl ester of 1 H-indene-3-carboxylic acid has been studied. The convenient syntheses of new functionalized organophosphorus acids and their derivatives with indan-1-carboxylic acid moieties have been proposed. Water-soluble sodium salts of the corresponding acids were also obtained. [ABSTRACT FROM AUTHOR]

The convenient methods of syntheses of new organophosphorus methane- and 4-substituted benzenenesulfonylamides from the trivalent organophosphorus acid esters and reactive N-chloromethyl N-methyl methanesulfonylamide, phosphorylated methylamines with NH- and NSi moieties and methane- and 4-substituted benzenesulfonyl chlorides were developed. The new types of functionalized organophosphorus derivatives of methane- and 4-substituted benzenesulfonic acids with P-C-N moieties were afforded in good yields. [ABSTRACT FROM AUTHOR]

Convenient methods of syntheses of new organophosphorus alkanesulfonylamides from the trivalent organophosphorus acid esters and reactive N-methyl N-chloromethyl methanesulfonylamide, phosphorylated methylamines with NH- and NSi moieties, trimethylsilyl vinylsulfonate, and N,N-diethylvinylsulfonamide were developed. The new types of functionalized organophosphorus derivatives of methane- and ethanesulfonic acids with P-C-N moieties were afforded in good yields. [ABSTRACT FROM PUBLISHER]

The various methods of aminomethylation of some PH-acids with proline and their derivatives are investigated. The numerous derivatives of proline and corresponding phosphonates, phosphonites, phosphinates, and phosphorane with proline moieties are presented. [ABSTRACT FROM AUTHOR]

The convenient syntheses of new aryl-substituted hydroxymethylphosphonic and methylenediphosphonic acids from the aromatic aldehydes, their derivatives, and phosphorous acid esters in the presence of the effective catalysts (trimethylsilyl trifluoromethanesulfonate, zinc chloride, and cadmium iodide) were developed. [ABSTRACT FROM AUTHOR]

It was found that a single-dose immunization of mice with Yersiniapseudotuberculosis porins OmpF and OmpC causes development of pathological changes in the deep layers of cerebral cortex characterized by dystrophic changes in the cells against the background of the increasing titer of specific antibodies. At the same time, the increased level of caspase-3 expression is observed in the neurons, which indicates induction of proapoptotic signaling pathways. The obtained results indicate potential ability of nonspecific pore-forming proteins of the outer membrane of Gram-negative bacteria to initiate development of degenerative changes in brain cells. [ABSTRACT FROM AUTHOR]

The convenient methods for the synthesis of new trimethylsilyl esters of aminomethylenediphosphonic acids are elaborated. The new substituted N-formylaminomethylenediphosphonates are obtained via the interaction of trimethylsilyl esters of methylenediphosphonic acids with a mixture of triethyl orthoformate and ethanol. Also boron trifluoride-diethyl etherate as an effective catalyst is used for the interaction of hydrochlorides of ethoxymethylene imines with diethyl trimethylsilyl phosphite. The corresponding aminomethylenediphosphonic acids are presented. [ABSTRACT FROM AUTHOR]

ABSTRACT The interaction of trimethylsilyl esters of trivalent organophosphorus acids containing PH and POSiMe3 groups with hydrochlorides of ethoxymethylene imines is a convenient method for the synthesis of new trimethylsilyl esters of N-unsubstituted aminomethylenebisorganophosphorus acids with three and four coordinated phosphorus. Also trimethylsilyl trifluoromethanesulfonate as effective catalyst is used for the similar interaction of hydrochlorides of ethoxymethylene imines with tris(trimethylsilyl)phosphite. The corresponding bisorganophosphorus acids and their derivatives are presented. [ABSTRACT FROM AUTHOR]

The new functionalized hydroxymethylphosphonic and methylenebis(phosphonic) acids are synthesized via reaction of tris(trimethylsilyl) phosphite and N -formyl derivatives of five-membered N-heterocycles in the presence of trimethylsilyl triflate. [ABSTRACT FROM AUTHOR]

• The new mono- and bis(aminomethylenediphosphonic) acids are synthesized in the presence of Me 3 SiOTf as a catalyst. • The catalytic schema of the resulting compounds syntheses include the formation of highly reactive iminium salts. • The target substances are structural analogues of well-known drugs and may be considered as promising polydentate ligands, antibacterial and antiviral compounds. The new mono- and bis(aminomethylenediphosphonic) acids are synthesized for the first time via unique reaction of tris(trimethylsilyl) phosphite and various N -formyl amino alkanols or bis(N -formyl amino) alkanes at the presence of effective catalyst – trimethylsilyl triflate under mild conditions. The further treatment of initially formed trimethylsilyl intermediates with the methanol excess resulted in the crystalline mono- and bis(aminomethylenediphosphonic) acids in high yields. The catalytic scheme of target substances formation is proposed and discussed in detail. The structures of target acids were confirmed by the 1H, 13C, 31P NMR spectra and high resolution mass spectra (HRMS). The resulting compounds are of great interest as perspective bioactive substances with versatile properties and effective polydentate ligands. [Display omitted] [ABSTRACT FROM AUTHOR]

• Study assesses HIV DRM among individuals experiencing ART failure in Russia. • 61.5% of study patients had HIV DRM detected. • 38.5% of patients had no DRM point at the insufficient ART adherence. • Observed DRM profiles differ between adults and children. • Region, gender, VL level and CD4 cell count had associations with DRM. Increasing HIV drug resistance is an important public health concern. The current study aimed to assess HIV drug resistance among people who live with HIV (PLWH) experiencing virological failure. Blood samples and epidemiological characteristics were collected in four Siberian regions from PLWH experiencing ART failure. Partial pol gene sequences were obtained for the study individuals. Drug resistance mutations (DRMs) were predicted using the Stanford HIVdb Program. The association of HIV DRM with epidemiological characteristics was estimated using logistic regression analysis. Further analysis was performed for children (0–14 y old) and adults (≥15 y old) separately. In total, 815 (89.4%) patients were included in the final dataset. Overall, 501 (61.5%) patients had DRM detected. NRTI DRM was more common in children, while NRTI+NNRTI DRM was more frequent in adults (P < 0.001). Krasnoyarsk region, male sex and high viral load were positively associated with the presence of DRM in adults, while higher CD4 cell count and PI/INSTI-based ART had a negative association. No association between epidemiological characteristics and DRM was identified in children. The remaining 38.5% of patients with virological failure had no DRM detected; those patients were likely to have insufficient ART adherence. Most (55.5%) patients had HIV CRF63_02A6, followed by sub-subtype A6 (39.2%). This study revealed poor ART adherence as a main factor driving ART failure among PLWH in the Siberian region. DRM was detected in over 60% of PLWH experiencing ART failure. The current results highlight an urgent need for the introduction of special programs focusing on ART adherence improvement. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Group II introns are mobile retroelements, capable of invading new sites in DNA. They are self-splicing ribozymes that complex with an intron-encoded protein to form a ribonucleoprotein that targets DNA after splicing. These molecules can invade DNA site-specifically, through a process known as retrohoming, or can invade ectopic sites through retrotransposition. Retrotransposition, in particular, can be strongly influenced by both environmental and cellular factors. Results: To investigate host factors that influence retrotransposition, we performed random insertional mutagenesis using the ISS1 transposon to generate a library of over 1000 mutants in Lactococcus lactis, the native host of the Ll.LtrB group II intron. By screening this library, we identified 92 mutants with increased retrotransposition frequencies (RTP-ups). We found that mutations in amino acid transport and metabolism tended to have increased retrotransposition frequencies. We further explored a subset of these RTP-up mutants, the most striking of which is a mutant in the ribosomal RNA methyltransferase rlmH, which exhibited a reproducible 20-fold increase in retrotransposition frequency. In vitro and in vivo experiments revealed that ribosomes in the rlmH mutant were defective in the m3Ψ modification and exhibited reduced binding to the intron RNA. Conclusions: Taken together, our results reinforce the importance of the native host organism in regulating group II intron retrotransposition. In particular, the evidence from the rlmH mutant suggests a role for ribosome modification in limiting rampant retrotransposition. [ABSTRACT FROM AUTHOR]

The paper aims to give a deep comprehensive analysis of the formal, notional and role characteristics of Ukrainian, Italian and English temporal adverbs, which express the time interrelation between a certain action and the actual moment and also identification of intertextual relations between these temporal adverbs. It is indicated that the adverbial lexical specificator, as an integral peripheral constituent of the functional-semantic field of temporality, is capable to reflect the coordination of the process relatively to such fundamental time orientation centers as the moment of speaking and the moment in the text. The author's strategy of classification of the relevant temporal adverbs is presented, the specificity of their functioning in three languages with different systems is amply illustrated with numerous examples from the national journalistic sources. During the process of systematization special attention was paid to the belonging of a certain linguistic unit to a definite timeline, the character of an adverbial temporal marker, the peculiarity of the correlation of the process with the actual moment as well as to the length of a distance between the event and the time orientation point. In order to clearly differentiate the classification components with greater and lesser specialization, the concept of the key and optional integrant of the distribution system was introduced. As a result of the multidimensional research of temporal adverbs in three languages with different grammatical organization, national-specific and common features of the adverbial expression of the correlation between the event and the real moment were identified. [ABSTRACT FROM AUTHOR]

The spliceosome is a large ribonucleoprotein complex that removes introns from pre-mRNAs. At its functional core lies the essential pre-mRNA processing factor 8 (Prp8) protein. Across diverse eukaryotes, this protein cofactor of RNA catalysis harbors a self-splicing element called an intein. Inteins in Prp8 are extremely pervasive and are found at 7 different sites in various species. Here, we focus on the Prp8 intein from Cryptococcus neoformans (Cne), a human fungal pathogen. We solved the crystal structure of this intein, revealing structural homology among protein splicing sequences in eukaryotes, including the Hedgehog C terminus. Working with the Cne Prp8 intein in a reporter assay, we find that the biologically relevant divalent metals copper and zinc inhibit intein splicing, albeit by 2 different mechanisms. Copper likely stimulates reversible modifications on a catalytically important cysteine, whereas zinc binds at the terminal asparagine and the same critical cysteine. Importantly, we also show that copper treatment inhibits Prp8 protein splicing in Cne. Lastly, an intein-containing Prp8 precursor model is presented, suggesting that metal-induced protein-splicing inhibition would disturb function of both Prp8 and the spliceosome. These results indicate that Prp8 protein splicing can be modulated, with potential functional implications for the spliceosome. [ABSTRACT FROM AUTHOR]

The new functionalized aminomethylenediphosphonates with moieties of various amino acids are synthesized via unique reaction of tris(trimethylsilyl) phosphite and N -formyl amino acids at the presence of effective catalyst – trimethylsilyl triflate under mild conditions. The further treatment of aminomethylenediphosphonates with the methanol excess resulted in the water-soluble functionalized aminomethylenediphosphonic acids. [ABSTRACT FROM AUTHOR]

The new functionalized hydroxymethylphosphonic and methylenediphosphonic acids are synthesized via unique reaction of tris(trimethylsilyl) phosphite and N -formyl N -heterocycles, N-substituted 4-piperidones, 3-quinuclidone, and 2-adamantanone at the presence of effective catalyst – trimethylsilyl triflate under mild conditions. [ABSTRACT FROM AUTHOR]

OmpF porin from the outer membrane of Yersinia pseudotuberculosis was cloned into pET-40b(+) plasmid. Using E. coli Rosetta (DE3) strain, MX medium, IPTG concentration of 0.2 mm and post-induction cultivation at 14°C overnight allowed us to obtain a water-soluble form of the recombinant protein (rs-OmpF). Rs-OmpF was shown to have the ordered spatial structure at the levels of secondary and tertiary structure. Rs-OmpF was found to be effective as diagnostic antigen in ELISA for pseudotuberculosis diagnostics. [ABSTRACT FROM AUTHOR]

The new functionalized hydroxymethylphosphonic and methylenediphosphonic acids are synthesized via unique reaction of tris(trimethylsilyl)phosphite and N-formyl derivatives of five-membered aza-heterocycles at the presence of effective catalyst-trimethylsilyl triflate. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • New aminomethylphosphinic acids with 4-hydroxypiperidine moieties were synthesized. • Reaction with various aminals proceeds under mild conditions to give PH-phosphinates. • New phosphinic acids were obtained by methanolysis. • Final compounds are promising bioactive substances and polydentate ligands. Abstract The convenient synthesis of new aminomethylphosphinic acids and their derivatives containing N -alkyl 4-hydroxypiperidines moieties was developed. The addition of bis(trimethylsiloxy)phosphine to N -alkyl 4-piperidones proceeds under mild conditions to give PH-phosphinates as key compounds for preparation of trimethylsilyl esters of above acids via interaction with various aminals. The further treatment of phosphinic acids trimethylsilyl esters with the methanol resulted in the water-soluble corresponding acids. The structures of aminomethylphosphinic acids and their precusors 1 – 3 with substituted piperidine moieties were confirmed by the 1H, 13C, 31P NMR spectra. [ABSTRACT FROM AUTHOR]

The recombinant OmpF porin of Yersinia pseudotuberculosis as a model of transmembrane protein of the β-barrel structural family was used to study low growth temperature effect on the structure of the produced inclusion bodies (IBs). This porin showed a very low expression level in E. coli at a growth temperature below optimal 37 °C. The introduction of a N-terminal hexahistidine tag into the mature porin molecule significantly increased the biosynthesis of the protein at low cultivation temperatures. The recombinant His-tagged porin (rOmpF-His) was expressed in E. coli at 30 and 18 °C as inclusion bodies (IB-30 and IB-18). The properties and structural organization of IBs, as well as the structure of rOmpF-His solubilized from the IBs with urea and SDS, were studied using turbidimetry, electron microscopy, dynamic light scattering, optical spectroscopy, and amyloid-specific dyes. IB-18, in comparison with IB-30, has a higher solubility in denaturants, suggesting a difference between IBs in the conformation of the associated polypeptide chains. The spectroscopic analysis revealed that rOmpF-His IBs have a high content of secondary structure with a tertiary-structure elements, including a native-like conformation, the proportion of which in IB-18 is higher than in IB-30. Solubilization of the porin from IBs is accompanied by a modification of its secondary structure. The studied IBs also contain amyloid-like structures. The results obtained in this study expand our knowledge of the structural organization of IBs formed by proteins of different structural classes and also have a contribution into the new approaches development of producing functionally active recombinant membrane proteins. [Display omitted] • Yersinia pseudotuberculosis OmpF porin forms the inclusion bodies (IBs) when expressed in E. coli. • N-terminal hexahistidine tag is required for efficient expression of the recombinant porin at low cultivation temperatures. • Porin species in native-like conformation are present in IBs and their content increases with decreasing growth temperature. • CD spectroscopy in combination with stepwise IB solubilization provides valid information on the porin secondary structure. [ABSTRACT FROM AUTHOR]

To gain a mechanistic insight in the functioning of the OmpF-like porin from Yersinia pseudotuberculosis (YOmpF), we compared the effect of pH variation on the ion channel activity of the protein in planar lipid bilayers and its binding to lipid membranes. The behavior of YOmpF channels upon acidification was similar to that previously described for Escherichia coli OmpF. In particular, a decrease in pH of the bathing solution resulted in a substantial reduction of YOmpF single channel conductance, accompanied by the emergence of subconductance states. Similar subconductance substates were elicited by the addition of lysophosphatidylcholine. This observation, made with porin channels for the first time, pointed to the relevance of lipid-protein interactions, in particular, the lipid curvature stress, to the appearance of subconductance states at acidic pH. Binding of YOmpF to membranes displayed rather modest dependence on pH, whereas the channel-forming potency of the protein tremendously decreased upon acidification. [ABSTRACT FROM AUTHOR]

Background: Compelled by the psychosocial implications of short stature, patients with short stature are increasingly undergoing distraction osteogenesis for cosmetic limb lengthening. To the degree that this is true, evaluation of the risks and benefits of this treatment are very important, but to date, there are few studies reporting on using distraction osteogenesis for this indication. Questions/purposes: We reviewed a group of patients undergoing cosmetic lower-extremity lengthening in terms of (1) soft tissue challenges, (2) bone-related complications, and (3) functional and subjective clinical outcomes. Methods: The study was retrospective by reviewing data from medical records and radiographs. Between 1983 and 2006, we treated 138 somatically normal patients with bilateral lower-limb distraction osteogenesis for cosmetic purposes at our center using an Ilizarov external fixator, of whom 131 (95%; 65 males, 66 females) had complete clinical and radiographic data a minimum of 1 year after treatment (mean, 6 years; range, 1-14 years) and were reviewed for this report. The mean age of these patients was 25 years (range, 14-68 years) and their mean preoperative height was 159 cm (range, 130-174 cm). One hundred twenty-four (95%) patients had lengthening of the tibia alone, of which 66 (53%) were monofocal and 58 (47%) were bifocal. Six patients (4.58%) had crossed contralateral lengthening of the femur and tibia and one patient (0.76%) had bilateral lengthening of the femur. The mean height gained was 6.9 cm (range, 2-13 cm), 7.3 cm (range, 3.5-13 cm) in males and 6.5 cm (range, 2-13 cm) in females. The mean lengthening, maturation, and external fixator indexes were 12 days/cm (range, 4.3-24 days/cm), 19 days/cm (range, 5.2-63 days/cm), and 31 days/cm (range, 12-78 days/cm), respectively. Results: Forty-eight patients (37%) had 59 complications related to treatment. Thirty-seven were soft tissue related (28%), of which 17 (46%) needed reinterventions, and 22 were bone related (17%), of which 16 (73%) needed reinterventions. At final followup, the outcome was excellent for 72 patients (55%), good for 52 (40%), satisfactory for six (4.58%), and poor for one (0.77%). One hundred thirty of 131 patients subjectively felt satisfied and had improved self-esteem. Conclusions: Distraction osteogenesis using the Ilizarov external fixator is an option for carefully selected motivated patients with awareness of this technique. Soft tissue and bone-related complications including those that necessitate reinterventions should be expected during the course of treatment, although most can be managed without permanent sequelae or disability. Future studies with more robust methods will need to determine whether the risks and benefits of this procedure are well balanced. Preoperative counseling, considering the ethical questions this procedure can raise, is of paramount importance for the patient to weigh the risk versus anticipated benefits. Studies from other centers will be important as we move forward. Level of Evidence: Level IV, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

This work aims to obtain new transformations and auto-Bäcklund transformations for generalized Liouville equations with exponential nonlinearity having a factor depending on the first derivatives. This paper discusses the construction of Bäcklund transformations for nonlinear partial second-order derivatives of the soliton type with logarithmic nonlinearity and hyperbolic linear parts. The construction of transformations is based on the method proposed by Clairin for second-order equations of the Monge–Ampere type. For the equations studied in the article, using the Bäcklund transformations, new equations are found, which make it possible to find solutions to the original nonlinear equations and reveal the internal connections between various integrable equations. [ABSTRACT FROM AUTHOR]

• The new methylenediphosphonates with non-proteinogenic amino acid and aminosulfonic acid moieties are synthesized in the presence of Me 3 SiOTf as a catalyst. • The catalytic schema of the resulting compounds syntheses include the formation of highly reactive iminium salts. • The target substances are structural analogues of well-known drugs and may be considered as promising polydentate ligands, antibacterial and antiviral compounds. The new non-proteinogenic amino acids with methylenebisphosphonic acids moieties are synthesized for the first time via unique reaction of tris(trimethylsilyl) phosphite and various N -formyl amino acids at the presence of effective catalyst – trimethylsilyl triflate under mild conditions. The further treatment of initially formed trimethylsilyl intermediates with the methanol excess resulted in the water-soluble non-proteinogenic amino acids with methylenebisphosphonic acids moieties in high yields. The catalytic scheme of target substances formation is proposed and discussed in detail. The structures of target functionalized amino acids and their precursors were confirmed by the 1H, 13C, 31P NMR spectra and high resolution mass spectra. The resulted compounds are of great interest as promising antiviral substances and effective ligands. [Display omitted] [ABSTRACT FROM AUTHOR]

Bacterium Yersinia ruckeri as a pathogen induces causative agent of intestinal fish disease called enteric redmouth disease (ERM) is known. In this study, outer membrane OmpF porin from the Y. ruckeri (YrOmpF) has been identified as a pathogenic factor which affects host macrophage activation and life cycle of eukaryotic cells. Using synthetic peptides corresponding to the sequences of the outer loops of YrOmpF L1 loop of the porin is most involved in the structure of B epitopes on the surface of the microbial cell it was found. T epitopes of the isolated YrOmpF trimer not only by linear, but also by discontinuous determinants, which is due to the secondary structure of the protein are represented. It was shown that YrOmpF was twice more cytotoxic to THP-1 cells (human monocytes, cancer cells) in comparison with CHH-1 cells (Oncorhynchus keta cardiac muscle cell, non-cancer cells). It was found YrOmpF induce cell cycle S-phase arrest in both normal CHH-1 and cancer THP-1 cells. In the cancer cells observed effect was most pronounce. In addition, we have observed an induction of apoptosis in THP-1 cell line treated with YrOmpF for 48 h at IC 50 (48.6 μg/ml). Significant cytotoxic effect of YrOmpF on primary mouse peritoneal macrophages been detected as well. Of note, co-incubation of macrophages with anti-YrOmpF antibodies could decrease the amount of lactate dehydrogenase, while the number of living cells significantly increased. YrOmpF stimulates the activity of the phagocytic bactericidal systems especially of the oxygen-independent subsystem it was found. Antibodies against YrOmpF decreased MPO release and CP synthesis by peritoneal macrophages and increased their viability. Image 1 • The outer loops of YrOmpF are involved in the formation of T and B antigenic epitopes. • YrOmpF induces cell cycle S-phase arrest and apoptosis in THP-1 cells. • Toxic effects of Y. ruckeri and YrOmpF on macrophages is reduced by anti-porin antibodies. • YrOmpF regulates the activity of murine peritoneal macrophages bactericidal systems. • Antibodies against YrOmpF enhanced synthesis of cationic proteins. [ABSTRACT FROM AUTHOR]

The convenient silicon-assisted synthesis of new aminomethylenebisphosphonic acids and their precursors was developed via unique methodology. So new aminomethylenebisphosphonic acids with quinolines moieties were obtained using suitable reaction of tris(trimethylsilyl) phosphite and N -formyl aminoquinolines catalyzed by trimethylsilyl triflate under mild conditions (20 °C). The initially formed intermediates – tetra (trimethylsilyl) aminomethylenebisphosphonates are transformed to target acids by methanolysis in high yields. The catalytic scheme of target substances formation is proposed and discussed in detail. The structures of aminomethylenebisphosphonic acids and their precursors with substituted quinoline moieties were confirmed by the 1H, 13C, 31P NMR spectra and high resolution mass spectra. Image 1 • The new quinolyl aminomethylenediphosphonates are synthesized in the presence of Me 3 SiOTf as a catalyst. • The resulting substances are structural analogues of well-known drugs and may be considered as promising polydentate ligands and plant growth regulating agents. [ABSTRACT FROM AUTHOR]

The new convenient synthesis of functionalized aryl and pyridyl aminomethylenebisphosphonic acids and their derivatives has been developed via silicon-assisted methodology. New functionalized aminomethylenebisphosphonic acids containing pyridines moieties were obtained using unique reaction of tris(trimethylsilyl) phosphite with N -formyl aminopyridines and trimethylsilyl triflate as a catalyst under mild conditions. Intermediates – tetra(trimethylsilyl) aminomethylenebisphosphonates formed, were converted to the target acids by further treatment with methanol excess. In contrast the corresponding tetraethyl aminomethylenebisphosphonates were synthesized under heating (130 °C) of four component mixture (diethyl trimethylsilyl phosphite, triethyl orthoformate, aryl- or pyridylamine, and diethyl phosphite) in the presence of zinc chloride catalyst. The catalytic schemes of target substances formation are proposed and thoroughly discussed. Image 1 • The new aryl and pyridyl aminomethylenediphosphonates are synthesized in the presence of Me 3 SiOTf or ZnCl 2 as catalysts.. • The catalytic schemes of the target compounds synthesis include the formation of highly reactive iminium salts. • The resulting substances are structural analogues of well-known drugs and may be considered as promising polydentate ligands. [ABSTRACT FROM AUTHOR]