Wound Closure Promotion by Leucine-Based Pseudo-Proteins: An In Vitro Study.

Our research explores leucine-based pseudo-proteins (LPPs) for advanced wound dressings, focusing on their effects on wound healing in an in vitro model. We assessed three types of LPP films for their ability to enhance wound closure rates and modulate cytokine production. They all significantly improved wound closure compared to traditional methods, with the 8L6 and copolymer films showing the most pronounced effects.

PEGylated Micro/Nanoparticles Based on Biodegradable Poly(Ester Amides): Preparation and Study of the Core-Shell Structure by Synchrotron Radiation-Based FTIR Microspectroscopy and Electron Microscopy.

Surface modification of drug-loaded particles with polyethylene glycol (PEG) chains is a powerful tool that promotes better transport of therapeutic agents, provides stability, and avoids their detection by the immune system. In this study, we used a new approach to synthesize a biodegradable poly(ester amide) (PEA) and PEGylating surfactant. These were employed to fabricate micro/nanoparticles with a core-shell structure.

Leucine-Based Pseudo-Proteins (LPPs) as Promising Biomaterials: A Study of Cell-Supporting Properties.

Scaffold-based systems have become essential in biomedical research, providing the possibility of building in vitro models that can better mimic tissue/organic physiology. A relatively new family of biomimetics-pseudo-proteins (PPs)-can therefore be considered especially promising in this context. Three different artificial leucine-based LPP films were tested in vitro as potential scaffolding materials.

Biomimetic Hybrid Systems for Tissue Engineering.

Tissue engineering approaches appear nowadays highly promising for the regeneration of injured/diseased tissues. Biomimetic scaffolds are continuously been developed to act as structural support for cell growth and proliferation as well as for the delivery of cells able to be differentiated, and also of bioactive molecules like growth factors and even signaling cues. The current research concerns materials employed to develop biological scaffolds with improved features as well as complex preparation techniques.

Biodegradable Nanoparticles Based on Pseudo-Proteins Show Promise as Carriers for Ophthalmic Drug Delivery.

Drug delivery to treat ocular diseases still is a challenge in ophthalmology. One way to achieve drug delivery that is investigated currently is topical administration of drug-loaded polymeric nanoparticles (NPs) that are able to penetrate ocular barriers. The purpose of this study was optimal preparation of NPs made from pseudo-proteins and evaluation of their ability to penetrate ocular tissues.

A Preliminary Evaluation of the Pro-Chondrogenic Potential of 3D-Bioprinted Poly(ester Urea) Scaffolds.

Degeneration of articular cartilage (AC) is a common healthcare issue that can result in significantly impaired function and mobility for affected patients. The avascular nature of the tissue strongly burdens its regenerative capacity contributing to the development of more serious conditions such as osteoarthritis. Recent advances in bioprinting have prompted the development of alternative tissue engineering therapies for the generation of AC.

Artificial Polymers made of α-amino Acids - Poly(Amino Acid)s, Pseudo-Poly(Amino Acid)s, Poly(Depsipeptide)s, and Pseudo-Proteins.

Degradable polymers (DPs) - "green materials" of the future, have an innumerable use in biomedicine, particularly in the fields of tissue engineering and drug delivery. Among these kind of materials naturally occurring polymers - proteins which constituted one of the most important "bricks of life" - α-amino acids (AAs) are highly suitable. A wide biomedical applicability of proteins is due to special properties such as a high affinity with tissues and releasing AAs upon biodegradation that means a nutritive potential for cells.

Oligoarginine Peptides, a New Family of Nicotinic Acetylcholine Receptor Inhibitors.

Many peptide ligands of nicotinic acetylcholine receptors (nAChRs) contain a large number of positively charged amino acid residues, a striking example being conotoxins RgIA and GeXIVA from marine mollusk venom, with an arginine content of >30%. To determine whether peptides built exclusively from arginine residues will interact with different nAChR subtypes or with their structural homologs such as the acetylcholine-binding protein and ligand-binding domain of the nAChR 9 subunit, we synthesized a series of R3, R6, R8, and R16 oligoarginines and investigated their activity by competition with radioiodinated -bungarotoxin, two-electrode voltage-clamp electrophysiology, and calcium imaging. R6 and longer peptides inhibited muscle-type nAChRs, 7 nAChRs, and 32 nAChRs in the micromolar range.

Perspectives of using of "aseptic" drains for abdominal drainage.

Aim: Aim of the study was to evaluate the effectiveness of using different types of drain tubes to prevent and reduce the drain-associated infection rate of abdominal drainage procedures.

Materials And Methods: 80 cases of used so called "standard", "coladerm" and "chlorhexidine" drain tubes for abdominal drainage were analysed. "Standard" drain tubes were used 35 times and "coladerm" and "chlorhexidine" tubes - 20 and 25 times respectively.

Generation of cortical neurons from human induced-pluripotent stem cells by biodegradable polymeric microspheres loaded with priming factors.

Ischemic stroke is often associated with loss of cortical neurons leading to various neurological deficits. A cell replacement based on stem cell transplantation to repair the damaged brain requires the generation of specific neuronal subtypes. Recently, induced pluripotent stem cells have been used to generate various subtypes of neurons in vitro for transplantation in stroke-damaged brains.

New poly(ester urea) derived from L-leucine: electrospun scaffolds loaded with antibacterial drugs and enzymes.

Electrospun scaffolds from an amino acid containing poly(ester urea) (PEU) were developed as promising materials in the biomedical field and specifically in tissue engineering applications. The selected poly(ester urea) was obtained with a high yield and molecular weight by reaction of phosgene with a bis(α-aminoacyl)-α,ω-diol-diester monomer. The polymer having L-leucine, 1,6-hexanediol and carbonic acid units had a semicrystalline character and relatively high glass transition and melting temperatures.

Improving the safety of Staphylococcus aureus polyvalent phages by their production on a Staphylococcus xylosus strain.

Team1 (vB_SauM_Team1) is a polyvalent staphylococcal phage belonging to the Myoviridae family. Phage Team1 was propagated on a Staphylococcus aureus strain and a non-pathogenic Staphylococcus xylosus strain used in industrial meat fermentation. The two Team1 preparations were compared with respect to their microbiological and genomic properties.

Arginine-based biodegradable ether-ester polymers with low cytotoxicity as potential gene carriers.

The success of gene therapy depends on safe and effective gene carriers. Despite being widely used, synthetic vectors based on poly(ethylenimine) (PEI), poly(l-lysine) (PLL), or poly(l-arginine) (poly-Arg) are not yet fully satisfactory. Thus, both improvement of established carriers and creation of new synthetic vectors are necessary.

Synthesis, properties and applications of biodegradable polymers derived from diols and dicarboxylic acids: from polyesters to poly(ester amide)s.

Poly(alkylene dicarboxylate)s constitute a family of biodegradable polymers with increasing interest for both commodity and speciality applications. Most of these polymers can be prepared from biobased diols and dicarboxylic acids such as 1,4-butanediol, succinic acid and carbohydrates. This review provides a current status report concerning synthesis, biodegradation and applications of a series of polymers that cover a wide range of properties, namely, materials from elastomeric to rigid characteristics that are suitable for applications such as hydrogels, soft tissue engineering, drug delivery systems and liquid crystals.

Cell compatible arginine containing cationic polymer: one-pot synthesis and preliminary biological assessment.

Synthetic cationic polymers are of interest as both nonviral vectors for intracellular gene delivery and antimicrobial agents. For both applications synthetic polymers containing guanidine groups are of special interest since such kind of organic compounds/polymers show a high transfection potential along with antibacterial activity. It is important that the delocalization of the positive charge of the cationic group in guanidine significantly decreases the toxicity compared to the ammonium functionality.

Non-covalent nano-adducts of co-poly(ester amide) and poly(ethylene glycol): preparation, characterization and model drug-release studies.

Biodegradable, biocompatible poly(ester amide)s (co-PEAs), composed of amino acids, fatty diols and carboxylic acids, have been synthesized. To improve the performance of co-PEAs in Federal Drug Administration-approved solvents such as water and ethanol, these polymers were complexed with poly(ethylene glycol) (PEG) of 10 kDa molecular mass have been prepared by solution blending. The non-covalent adducts were purified by precipitation into hexanes.

In-vivo biocompatibility evaluation of stents coated with a new biodegradable elastomeric and functional polymer.

Background: In-stent restenosis may be prevented by impregnating an antiproliferative agent in a polymer from a stent platform. This approach requires both an antiproliferative agent effective in small doses and a biocompatible polymer.

Methods: A series of new biodegradable elastomeric poly(ester-amide)(co-PEA) polymers having functional carboxyl groups for drug conjugation were synthesized from non-toxic building blocks.

A novel sustained-release matrix based on biodegradable poly(ester amide)s and impregnated with bacteriophages and an antibiotic shows promise in management of infected venous stasis ulcers and other poorly healing wounds.

Healing of poorly vascularized and venous stasis ulcers is often refractory to therapy, particularly when they are infected. Systemic antibiotic therapy may be of little benefit in this setting because of poor penetration of the antibiotic into the wound and the frequent associated emergence of bacterial strains resistant to common antimicrobial agents. Given the clinical significance of these problems, there is a need to explore alternative management approaches for these difficult-to-treat wounds.