Tb(III) complexes with nonyl-substituted calix[4]arenes as building blocks of hydrophilic luminescent mixed polydiacetylene-based aggregates

© 2018 The present work for the first time introduces PDA-based vesicles as convenient supporters of luminescent water insoluble Tb3+ complexes. The specific cyclophanic structure of the ligands, where upper and lower calix[4]arene rims are decorated by nonyl- and chelating groups correspondingly provides both complex formation with Tb3+ ions with the coordination of the latter via two 1,3-diketonate groups and self- or mixed aggregation of the complexes. The conditions of the self-aggregation of the Tb3+ complexes are revealed, although the self-aggregates are unstable being converted into the nanosized precipitates which tend to further aggregation and phase separation. The complexes exhibit Tb(III)-centered luminescence which tends to change in time following the phase separation processes. The embedding of the Tb3+ complexes into the PDA-based vesicles results in the mixed aggregates with significant Tb(III)-centered luminescence and significant colloidal stability. The latter arises from high negative electrokinetic potential values due to exterior carboxylic/carboxylate groups of the PDA vesicles

A Novel Peptide Derived from Human Pancreatitis-Associated Protein Inhibits Inflammation In Vivo and In Vitro and Blocks NF-Kappa B Signaling Pathway

BACKGROUND: Pancreatitis-associated protein (PAP) is a pancreatic secretory protein belongs to the group VII of C-type lectin family. Emerging evidence suggests that PAP plays a protective effect in inflammatory diseases. In the present study, we newly identified a 16-amino-acid peptide (named PAPep) derived from C-type lectin-like domain (CTLD) of human PAP with potent anti-inflammatory activity using both in vivo and in vitro assays. METHODOLOGY/PRINCIPAL FINDINGS: We assessed the anti-inflammatory effect of PAPep on endotoxin-induced uveitis (EIU) in rats and demonstrated that intravitreal pretreatment of PAPep concentration-dependently attenuated clinical manifestation of EIU rats, reduced protein leakage and cell infiltration into the aqueous humor (AqH), suppressed tumor necrosis factor (TNF)-α, interleukin (IL)-6, intercellular adhesion molecule-1 (ICAM-1) and monocyte chemoattractant protein (MCP)-1 production in ocular tissues, and improved histopathologic manifestation of EIU. Furthermore, PAPep suppressed the LPS-induced mRNA expression of TNF-α and IL-6 in RAW 264.7 cells, inhibited protein expression of ICAM-1 in TNF-α-stimulated human umbilical vein endothelial cells (HUVECs) as well as U937 cells adhesion to HUVECs. Western blot analysis in ocular tissues and different cell lines revealed that the possible mechanism for this anti-inflammatory effect of PAPep may depend on its ability to inhibit the activation of NF-kB signaling pathway. CONCLUSIONS/SIGNIFICANCE: Our studies provide the first evidence that the sequence of PAPep is within the critically active region for the anti-inflammatory function of PAP and the peptide may be a promising candidate for the management of ocular inflammatory diseases

Photopolymerization of polydiacetylene in hybrid liposomes:Effect of polymerization on stability and response to pathogenic bacterial toxins

Liposomes containing lipids and polydiacetylene (PDA) are hybrid systems encompassing both a fluid phospholipid membrane and a polymer scaffold (PDA). However, the biophysical role of PDA in such liposomes is not well understood. In this report, we studied the effects of photopolymerization of PDA on the stability of lipid-PDA liposomes, and their sensitivity to selected purified toxins and bacterial supernatants, using a fluorescence assay. Of the three different types of liposomes with variable lipid chain lengths that were chosen, the degree of polymerization had a significant impact on the long-term stability, and response, to external microbial exotoxins secreted by pathogenic bacteria, namely, Staphylococcus aureus and Pseudomonas aeruginosa. The degree of polymerization of TCDA played an important role in lipid-chain-length-dependent stabilization of lipid-PDA liposomes, as well as in their response to bacterial toxins of S. aureus and P. aeruginosa.</p

Scavenging neurotoxic aldehydes using lysine carbon dots

Reactive aldehydes generated in cells and tissues are associated with adverse physiological effects. Dihydroxyphenylacetaldehyde (DOPAL), the biogenic aldehyde enzymatically produced from dopamine, is cytotoxic, generates reactive oxygen species, and triggers aggregation of proteins such as α-synuclein implicated in Parkinson's disease. Here, we demonstrate that carbon dots (C-dots) prepared from lysine as the carbonaceous precursor bind DOPAL molecules through interactions between the aldehyde units and amine residues on the C-dot surface. A set of biophysical and in vitro experiments attests to attenuation of the adverse biological activity of DOPAL. In particular, we show that the lysine-C-dots inhibit DOPAL-induced α-synuclein oligomerization and cytotoxicity. This work underlines the potential of lysine-C-dots as an effective therapeutic vehicle for aldehyde scavenging

The Site's Capabilities for Analyzing Consumer Behavior and Promoting Products on The B2b Market

The importance of developing a competent website for the company, which allows analyzing consumer behavior, increasing brand loyalty, and increasing the company's profit, is determined. The article identifies the main differences in the behavior of b2c and b2b users on the site and examines the user's path on the b2b company's website. The paper analyzes the main tools that make the user's interaction with the site more comfortable and effective.Определена важность разработки грамотного сайта для компании, позволяющего анализировать поведение потребителей, повышать лояльность к бренду, и увеличивать прибыль компании. В статье определены основные различия поведения b2c и b2b пользователей на сайте и изучен путь пользователя на сайте компании b2b. В работе проанализированы основные инструменты, позволяющие сделать взаимодействие пользователя с сайтом более комфортным и эффективным

Tb(III) complexes with nonyl-substituted calix[4]arenes as building blocks of hydrophilic luminescent mixed polydiacetylene-based aggregates

© 2018 The present work for the first time introduces PDA-based vesicles as convenient supporters of luminescent water insoluble Tb3+ complexes. The specific cyclophanic structure of the ligands, where upper and lower calix[4]arene rims are decorated by nonyl- and chelating groups correspondingly provides both complex formation with Tb3+ ions with the coordination of the latter via two 1,3-diketonate groups and self- or mixed aggregation of the complexes. The conditions of the self-aggregation of the Tb3+ complexes are revealed, although the self-aggregates are unstable being converted into the nanosized precipitates which tend to further aggregation and phase separation. The complexes exhibit Tb(III)-centered luminescence which tends to change in time following the phase separation processes. The embedding of the Tb3+ complexes into the PDA-based vesicles results in the mixed aggregates with significant Tb(III)-centered luminescence and significant colloidal stability. The latter arises from high negative electrokinetic potential values due to exterior carboxylic/carboxylate groups of the PDA vesicles