Therapies Targeted at Non-Coding RNAs in Prevention and Limitation of Myocardial Infarction and Subsequent Cardiac Remodeling—Current Experience and Perspectives

Myocardial infarction is one of the major causes of mortality worldwide and is a main cause of heart failure. This disease appears as a final point of atherosclerotic plaque progression, destabilization, and rupture. As a consequence of cardiomyocytes death during the infarction, the heart undergoes unfavorable cardiac remodeling, which results in its failure. Therefore, therapies aimed to limit the processes of atherosclerotic plaque progression, cardiac damage during the infarction, and subsequent remodeling are urgently warranted. A hopeful therapeutic option for the future medicine is targeting and regulating non-coding RNA (ncRNA), like microRNA, circular RNA (circRNA), or long non-coding RNA (lncRNA). In this review, the approaches targeted at ncRNAs participating in the aforementioned pathophysiological processes involved in myocardial infarction and their outcomes in preclinical studies have been concisely presented.     

PAN‐based fibers modified with two‐component ceramic nanoparticles

The authors determined conditions for manufacturing PAN precursor fibers containing a system of two nanoadditives, montmorillonite (MMT), and hydroxyapatite (HAp) in their structure. The PAN precursor fibers thus obtained are characterized by a tenacity of more than 30 cN/tex and a total volume of pores at the level of 0.29 cm³/g. Furthermore, it was found that the use of nanoadditives entails the remodeling of the paracrystalline structure of PAN fibers into a strictly crystalline one. This is accompanied by a decrease in spacing between MMT layers combined with their partial exfoliation. The fibers thus obtained, after being carbonized, will be used for medical applications. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Performance of carbon-carbon supercapacitors based on organic, aqueous and ionic liquid electrolytes

Properties of capacitors working with the same carbon electrodes (activated carbon cloth) and three types of electrolytes: aqueous, organic and ionic liquids were compared. Capacitors filled with ionic liquids worked at a potential difference of 3.5 V, their solutions in AN and PC were charged up to the potential difference of 3 V, classical organic systems to 2.5 V and aqueous to 1 V. Cyclic voltammetry, galvanostatic charging/discharging and impedance spectroscopy were used to characterize these capacitors. The highest specific energy was recorded for the device working with ionic liquids, while the highest power is characteristic for the device filled with aqueous H₂SO₄ electrolyte. Aqueous electrolytes led to energy density an order of magnitude lower in comparison to that characteristic of ionic liquids.     

Protein Arginine Methyltransferase (PRMT) Inhibitors—AMI-1 and SAH Are Effective in Attenuating Rhabdomyosarcoma Growth and Proliferation in Cell Cultures

Rhabdomyosarcoma (RMS) is a malignant soft tissue cancer that develops mostly in children and young adults. With regard to histopathology, four rhabdomyosarcoma types are distinguishable: embryonal, alveolar, pleomorphic and spindle/sclerosing. Currently, increased amounts of evidence indicate that not only gene mutations, but also epigenetic modifications may be involved in the development of RMS. Epigenomic changes regulate the chromatin architecture and affect the interaction between DNA strands, histones and chromatin binding proteins, thus, are able to control gene expression. The main aim of the study was to assess the role of protein arginine methyltransferases (PRMT) in the cellular biology of rhabdomyosarcoma. In the study we used two pan-inhibitors of PRMT, called AMI-1 and SAH, and evaluated their effects on proliferation and apoptosis of RMS cells. We observed that AMI-1 and SAH reduce the invasive phenotype of rhabdomyosarcoma cells by decreasing their proliferation rate, cell viability and ability to form cell colonies. In addition, microarray analysis revealed that these inhibitors attenuate the activity of the PI3K-Akt signaling pathway and affect expression of genes related to it.     

2‐Acetyl‐4,6,8,10,12‐Pentanitro‐Hexaazaisowurtzitane (PNAIW) Preparation and Properties

2‐Acetyl‐4,6,8,10,12‐pentanitro‐2,4,6,8,10,12‐hexaazaisowurtzitane (PNAIW) is formed in the last step of nitration of acetyl isowurtzitane derivatives. The amount of the PNAIW formed depends on the conditions of the nitration reaction (temperature, time, and nitrating mixture used) and on the type of the starting acetyl intermediate. The highest PNAIW yields (30 %) were obtained by nitrating 2,6,8,12‐tetraacetylhexaazaisowurtzitane (TAIW) at 60 °C for half an hour using HNO₃/H₂SO₄ nitrating mixture. HPLC, NMR, FTIR, and DSC measurements were used in the study and their results are reported.     

A Multiplex Assay to Assess the Transaminase Activity toward Chemically Diverse Amine Donors

The development of methods to engineer and immobilize amine transaminases (ATAs) to improve their functionality and operational stability is gaining momentum. The quest for robust, fast, and easy-to-use methods to screen the activity of large collections of transaminases, is essential. This work presents a novel and multiplex fluorescence-based kinetic assay to assess ATA activity using 4-dimethylamino-1-naphthaldehyde as an amine acceptor. The developed assay allowed us to screen a battery of amine donors using free and immobilized ATAs from different microbial sources as biocatalysts. As a result, using chromatographic methods, 4-hydroxybenzylamine was identified as the best amine donor for the amination of 5-(hydroxymethyl)furfural. Finally, we adapted this method to determine the apparent Michaelis-Menten parameters of a model immobilized ATA at the microscopic (single-particle) level. Our studies promote the use of this multiplex, multidimensional assay to screen ATAs for further improvement.     

Network structure/mechanical property relationship in crosslinked dimethacrylates of different chain lengths

In this article, the syntheses of three novel dimethacrylates of different chain lengths as well as the mechanical and thermal properties of their copolymers with methyl methacrylate and styrene were studied. The monomers were prepared by the reaction of glycidyl methacrylate with dicarboxylic acid esters obtained from maleic anhydride and ethylene, 1,4‐butylene and 1,6‐hexylene glycols. The addition reaction of glycidyl methacrylate and the acidic compound was carried out in the presence of basic catalyst, tetraethylammonium bromide. The monomers were UV‐copolymerized with methyl methacrylate and styrene in the presence of a photoinitiator which was 2,2‐dimethoxy‐2‐phenyloacetophenone. The prepared polymers were subjected to different studies concerning evaluation of their flexural properties, thermal stability, dynamic mechanical behavior as well as qualitative estimation of the content of unreacted double bonds. The dependence of glass transition temperatures (T_g) as well as degree of inhomogeneity on the crosslinking density has been examined in different copolymer systems. Evidence that the dependence of the T_g on the crosslinking density is not straightforward is presented. Dynamic mechanical measurements have demonstrated that the heterogeneity of the crosslinked polymers depends strongly on the crosslinking density of the system and the nature of methacrylate monomers used. Depending on the monomer size as well as its functionality, the resultant polymer may have features such as crosslinks or residual unsaturations that influence and define the properties of the materials. It is proved that the new dimethacrylates change their functionality in copolymerization with different monovinyl monomers. Also, the degree of unsaturated bonds conversion was found to be growing with the amount of monovinyl in the copolymer. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Effects of metal cations on betanin stability in aqueous-organic solutions

An effect of metal cations on betanin stability was investigated in aqueous and organic-aqueous solutions. The presence of organic solvents (methanol, ethanol, and acetonitrile) affects substantially the pigments decomposition in acidic media induced by metal cations whose degrading action in such media is significantly higher than in aqueous solutions. The influence of Cu²⁺ on the stability was studied by spectrophotometry in more detailed manner, because of its ability to form complexes with betanin. The possibility of a complex formation between betanin and Ni²⁺ was also stated at pH 7–8; its relatively high stability in aqueous samples was observed. A presence of numerous products of betanin decomposition was detected in the wavelength range 380–500 nm in spectra obtained for most of metal cations investigated, especially for higher concentrations of the organic solvents.