Viscoelastic behaviour of hyaluronic acid formulations containing carvacrol prodrugs with antibacterial properties

Synthesis and Characterization of Electrospun Sorbent for the Solid-Phase Extraction of Fluoroquinolones in Human Plasma and Their UHPLC-PDA Determination

In this work we investigated the synthesis and the characterization of electrospun polyacrylonitrile (PAN) and polymethyl methacrylate (PMMA) stabilized in air, made in a 5:1 ratio, used as sorbent for the solid-phase extraction of fluoroquinolones in plasma samples and the following quantification in UHPLC-PDA. Preliminary analyses of viscosity were carried out on the polymer solution to be sure about the electrospinability. Characterizations were performed on the electrospun membrane to evaluate the morphology (SEM scanning electron microscopy and AFM atomic force microscopy), the thermal degradation behavior (TGA thermogravimetric analysis), the porosity and the surface area (BET, Brunauer Emmett Teller), and the quantitative and qualitative distribution of atomic structures (FTIR infrared analysis in Fourier transform and EDX Energy Dispersive X-ray analysis). A solid-phase extraction method was developed by studying parameters such as the amount of sorbent and the pH of the sample. Finally, a UHPLC-PDA method for the analysis of fluoroquinolones was developed and validated in accordance with the guidelines and successfully applied. The use of the prepared sorbent combined with UHPLC-PDA has allowed the development of a method whose strengths are its speed, accuracy, sensitivity, and high recoveries.

Hyaluronic acid association with bacterial, fungal and viral infections: Can hyaluronic acid be used as an antimicrobial polymer for biomedical and pharmaceutical applications?

The relationships between hyaluronic acid (HA) and pathological microorganisms incite new understandings on microbial infection, tissue penetration, disease progression and lastly, potential treatments. These understandings are important for the advancement of next generation antimicrobial therapeutical strategies for the control of healthcare-associated infections. Herein, this review will focus on the interplay between HA, bacteria, fungi, and viruses. This review will also comprehensively detail and discuss the antimicrobial activity displayed by various HA molecular weights for a variety of biomedical and pharmaceutical applications, including microbiology, pharmaceutics, and tissue engineering.

Preparation, Characterization, and Biological Evaluation of a Hydrophilic Peptide Loaded on PEG-PLGA Nanoparticles

The encapsulation of peptides and proteins in nanosystems has been extensively investigated for masking unfavorable biopharmaceutical properties, including short half-life and poor permeation through biological membranes. Therefore, the aim of this work was to encapsulate a small antimicrobial hydrophilic peptide (H-Ser-Pro-Trp-Thr-NH2, FS10) in PEG-PLGA (polyethylene glycol-poly lactic acid-co-glycolic acid) nanoparticles (Nps) and thereby overcome the common limitations of hydrophilic drugs, which because they facilitate water absorption suffer from rapid degradation. FS10 is structurally related to the well-known RNAIII inhibiting peptide (RIP) and inhibits S. aureus biofilm formation. Various parameters, including different method (double emulsion and nanoprecipitation), pH of the aqueous phase and polymeric composition, were investigated to load FS10 into PEG-PLGA nanoparticles. The combination of different strategies resulted in an encapsulation efficiency of around 25% for both the double emulsion and the nanoprecipitation method. It was found that the most influential parameters were the pH—which tailors the peptides charge—and the polymeric composition. FS10-PEG-PLGA nanoparticles, obtained under optimized parameters, showed size lower than 180 nm with zeta potential values ranging from −11 to −21 mV. In vitro release studies showed that the Nps had an initial burst release of 48−63%, followed by a continuous drug release up to 21 h, probably caused by the porous character of the Nps. Furthermore, transmission electron microscopy (TEM) analysis revealed particles with a spherical morphology and size of around 100 nm. Antimicrobial assay showed that the minimum inhibitory concentration (MIC) of the FS10-loaded Nps, against S. aureus strains, was lower (>128 µg/mL) than that of the free FS10 (>256 µg/mL). The main goal of this work was to develop polymeric drug delivery systems aiming at protecting the peptide from a fast degradation, thus improving its accumulation in the target site and increasing the drug-bacterial membrane interactions.

Wound-Healing Promotion and Anti-Inflammatory Properties of Carvacrol Prodrugs/Hyaluronic Acid Formulations

Background. Wound healing (WH) is a complex process involving several stages, such as hemostasis, inflammation, re-epithelialization, and remodeling. Many factors can impair WH, and different pharmacological approaches were studied to date, but the increase in antibiotic resistance, invasiveness, treatment duration, and high cost, have often hampered the resolution of the wound. In this study, we investigated the possible application of water-soluble carvacrol prodrugs (WSCPs) and hyaluronic acid (HA) and their formulations (WSCPs/HA) to improve WH and regulate the inflammatory response. Materials and methods. Firstly, the cytotoxicity of 0.1, 1 and 10 µg/mL of HA, WSCPs and WSCPs/HA formulations were evaluated on HaCaT cells and THP-1 cell lines. The ability of WSCPs/HA formulations to modulate wound repair was evaluated in an in vitro model of WH, using HaCaT cells at 6, 18, and 24 h. The expression of WH mediators, after wound closure was determined by qRT-PCR. Following, we polarized THP-1 cells in M1/M2-like macrophages and tested the anti-inflammatory properties of WSCPs/HA formulations. After, we tested the in vitro WH model for the effects of conditioned medium (CM) from M1/M2-like cells cultured in the presence of WSCPs/HA. Results. Results showed that WSCPs/HA formulations were able to significantly raise the wound closure rate, compared to the single constituents, promoting a complete wound closure after 18 h for WSCP1/HA (10 µg/mL) and after 24 h for WSCP2/HA (10 µg/mL), modulating the MMPs, TGFβ, and COX-2 gene expression. The effects of CM derived from M1/M2 polarized cells cultured in the presence of WSCPs/HA determined WH regulation, with a better ability of the WSCP2/HA formulation to modulate the time-dependent expression of reparative and inflammatory mediators. Conclusion. Our data underline the possible application of WSCPs/HA formulations as bioactive agents for the regulation of the wound repair process by the modulation of inflammatory and remodeling phases, affecting the activity of immune cells.

Scoping review and interpretation of myofascial pain/fibromyalgia syndrome: An attempt to assemble a medical puzzle

BACKGROUND

Myofascial Pain Syndrome (MPS) is a common, overlooked, and underdiagnosed condition and has significant burden. MPS is often dismissed by clinicians while patients remain in pain for years. MPS can evolve into fibromyalgia, however, effective treatments for both are lacking due to absence of a clear mechanism. Many studies focus on central sensitization. Therefore, the purpose of this scoping review is to systematically search cross-disciplinary empirical studies of MPS, focusing on mechanical aspects, and suggest an organic mechanism explaining how it might evolve into fibromyalgia. Hopefully, it will advance our understanding of this disease.

METHODS

Systematically searched multiple phrases in MEDLINE, EMBASE, COCHRANE, PEDro, and medRxiv, majority with no time limit. Inclusion/exclusion based on title and abstract, then full text inspection. Additional literature added on relevant side topics. Review follows PRISMA-ScR guidelines. PROSPERO yet to adapt registration for scoping reviews.

FINDINGS

799 records included. Fascia can adapt to various states by reversibly changing biomechanical and physical properties. Trigger points, tension, and pain are a hallmark of MPS. Myofibroblasts play a role in sustained myofascial tension. Tension can propagate in fascia, possibly supporting a tensegrity framework. Movement and mechanical interventions treat and prevent MPS, while living sedentarily predisposes to MPS and recurrence.

CONCLUSIONS

MPS can be seen as a pathological state of imbalance in a natural process; manifesting from the inherent properties of the fascia, triggered by a disrupted biomechanical interplay. MPS might evolve into fibromyalgia through deranged myofibroblasts in connective tissue ("fascial armoring"). Movement is an underemployed requisite in modern lifestyle. Lifestyle is linked to pain and suffering. The mechanism of needling is suggested to be more mechanical than currently thought. A "global percutaneous needle fasciotomy" that respects tensegrity principles may treat MPS/fibromyalgia more effectively. "Functional-somatic syndromes" can be seen as one entity (myofibroblast-generated-tensegrity-tension), sharing a common rheuma-psycho-neurological mechanism.