Hyaluronate effect on bacterial biofilm in ENT district infections: a review

The current status of stimuli-responsive nanotechnologies on orthopedic titanium implant surfaces

With the continuous innovation and breakthrough of nanomedical technology, stimuli-responsive nanotechnology has been gradually applied to the surface modification of titanium implants to achieve brilliant antibacterial activity and promoted osteogenesis. Regarding to the different physiological and pathological microenvironment around implants before and after surgery, these surface nanomodifications are designed to respond to different stimuli and environmental changes in a timely, efficient, and specific way/manner. Here, we focus on the materials related to stimuli-responsive nanotechnology on titanium implant surface modification, including metals and their compounds, polymer materials and other materials. In addition, the mechanism of different response types is introduced according to different activation stimuli, including magnetic, electrical, photic, radio frequency and ultrasonic stimuli, pH and enzymatic stimuli (the internal stimuli). Meanwhile, the associated functions, potential applications and developing prospect were discussion.

Hyaluronic Acid in Rhinology: Its Uses, Advantages and Drawbacks-A Review

Hyaluronic acid has been increasingly involved in recent research due to its many chemical and physical properties. This is a review of the literature for studies involving the use of hyaluronic acid in rhinology. Hyaluronic acid washes and irrigation have been increasingly used in chronic sinusitis medical therapy and post-operatively with mixed results. It has also been shown to play a role in the treatment of nasal polyposis, allergic rhinitis, acute rhinosinusitis and empty nose syndrome. Its effect on biofilm in many disease entities has also been studied. HA is being recently used as ancillary treatment for several rhinologic conditions such as post-operative endoscopy care and chronic sinonasal infections. The properties of HA have intrigued researchers over the past years particularly in biofilm management, healing and inflammation.

Methods and criteria for validating the multimodal functions of perinatal derivatives when used in oncological and antimicrobial applications

Perinatal derivatives or PnDs refer to tissues, cells and secretomes from perinatal, or birth-associated tissues. In the past 2 decades PnDs have been highly investigated for their multimodal mechanisms of action that have been exploited in various disease settings, including in different cancers and infections. Indeed, there is growing evidence that PnDs possess anticancer and antimicrobial activities, but an urgent issue that needs to be addressed is the reproducible evaluation of efficacy, both in vitro and in vivo. Herein we present the most commonly used functional assays for the assessment of antitumor and antimicrobial properties of PnDs, and we discuss their advantages and disadvantages in assessing the functionality. This review is part of a quadrinomial series on functional assays for the validation of PnDs spanning biological functions such as immunomodulation, anticancer and antimicrobial, wound healing, and regeneration.

Cytocompatible, soft and thick brush-modified scaffolds with prolonged antibacterial effect to mitigate wound infections

Biomedical device or implant-associated infections caused by pathogenic bacteria are a major clinical issue, and their prevention and/or treatment remains a challenging task. Infection-resistant antimicrobial coatings with impressive cytocompatibility offer a step towards addressing this problem. Herein, we report a new strategy for constructing highly antibacterial as well as cytocompatible mixed polymer brushes onto the surface of 3D printed scaffold made of biodegradable tartaric acid-based aliphatic polyester blends. The mixed brushes were nothing but a combination of poly(3-dimethyl-(methacryloyloxyethyl) ammonium propane sulfonate) (polyDMAPS) and poly((oligo ethylene glycol) methyl ether methacrylate) (polyPEGMA) with varying chain length (n) of the ethylene glycol unit (n = 1, 6, 11, and 21). Both homo and copolymeric brushes of polyDMAPS with polyPEGMA exhibited antibacterial efficacy against both Gram positive and Gram negative pathogens such as E. coli (Escherichia coli) and S. aureus (Staphylococcus aureus) because of the combined action of bacteriostatic effects originating from strongly hydrated layers present in zwitterionic (polyDMAPS) and hydrophilic (polyPEGMA) copolymer brushes. Interestingly, a mixed polymer brush comprising polyDMAPS and polyPEGMA (ethylene glycol chain unit of 21) at 50/50 ratio provided zero bacterial growth and almost 100% cytocompatibility (tested using L929 mouse fibroblast cells), making the brush-modified biodegradable substrate an excellent choice for an infection-resistant and cytocompatible surface. An attempt was made to understand their extraordinary performance with the help of contact angle, surface charge analysis and nanoindentation study, which revealed the formation of a hydrophilic, almost neutral, very soft surface (99.99% reduction in hardness and modulus) after modification with the mixed brushes. This may completely suppress bacterial adhesion. Animal studies demonstrated that these brush-modified scaffolds are biocompatible and can mitigate wound infections. Overall, this study shows that the fascinating combination of an infection-resistant and cytocompatible surface can be generated on biodegradable polymeric surfaces by modulating the surface hardness, flexibility and hydrophilicity by selecting appropriate functionality of the copolymeric brushes grafted onto them, making them ideal non-leaching, anti-infective, hemocompatible and cytocompatible coatings for biodegradable implants.

Decellularization of Wharton’s Jelly Increases Its Bioactivity and Antibacterial Properties

The field of regenerative medicine has recently seen an emerging trend toward decellularized extracellular matrix (ECM) as a biological scaffold for stem cell-delivery. Human umbilical cord represents a valuable opportunity from both technical and ethical point of view to obtain allogenic ECM. Herein, we established a protocol, allowing the full removal of cell membranes and nuclei moieties from Wharton’s jelly (WJ) tissue. No alterations in the ECM components (i.e., collagen, GAG content, and growth factors), physical (i.e., porosity and swelling) and mechanical (i.e., linear tensile modulus) properties were noticed following WJ processing. Furthermore, no effect of the tissue processing on macromolecules and growth factors retention was observed, assuring thus a suitable bioactive matrix for cell maintenance upon recellularization. Based on the in vitro and in vivo biodegradability and stromal cell homing capabilities, decellularized WJ could provide an ideal substrate for stromal cells adhesion and colonization. Interestingly, the tissue processing increased the antibacterial and antiadhesive properties of WJ against Staphylococcus aureus and Staphylococcus epidermidis pathogens. Altogether, our results indicate that decellularized WJ matrix is able to limit Staphylococcus-related infections and to promote stromal cell homing, thus offering a versatile scaffold for tissue regenerative medicine.

Antibacterial and Immunomodulatory Properties of Acellular Wharton’s Jelly Matrix

Of all biologic matrices, decellularized tissues have emerged as a promising tool in the field of regenerative medicine. Few empirical clinical studies have shown that Wharton’s jelly (WJ) of the human umbilical cord promotes wound closure and reduces wound-related infections. In this scope, we herein investigated whether decellularized (DC)-WJ could be used as an engineered biomaterial. In comparison with devitalized (DV)-WJ, our results showed an inherent effect of DC-WJ on Gram positive (S. aureus and S. epidermidis) and Gram negative (E. coli and P. aeruginosa) growth and adhesion. Although DC-WJ activated the neutrophils and monocytes in a comparable magnitude to DV-WJ, macrophages modulated their phenotypes and polarization states from the resting M0 phenotype to the hybrid M1/M2 phenotype in the presence of DC-WJ. M1 phenotype was predominant in the presence of DV-WJ. Finally, the subcutaneous implantation of DC-WJ showed total resorption after three weeks of implantation without any sign of foreign body reaction. These significant data shed light on the potential regenerative application of DC-WJ in providing a suitable biomaterial for tissue regenerative medicine and an ideal strategy to prevent wound-associated infections.

Use of a novel sealant film in head and neck surgery

In head and neck surgery, sealant films represent a useful adjunct to ensure a reinforcement preventing leakages, dehiscence or oozing. The aim of this pilot study is to present the potential applications of a new sealant sheet in head and neck surgery, reporting outcomes, advantages and limitations. The sample included 32 patients, that underwent oncologic or elective surgery between January 2019 and January 2021 at the Cattinara Hospital in Trieste, Italy. Data regarding the patient, the surgical procedure and the postoperative course over hospitalization in terms of surgical complications were retrospectively collected. In this study, nor complication during the regular follow-up period occurred neither difficulties emerged in TP use in any head and neck subsites. In our experience, TP represented a valid aid in suture strengthening, easy to apply and suitable also for oncologic surgery in which the closure of some surgical defects may need a greater sealing effect.

Non-steroid, non-antibiotic anti-biofilm therapy for the treatment of chronic rhinosinusitis: a systematic review

OBJECTIVE

Chronic rhinosinusitis patients with biofilms cultured from their sinonasal cavity have greater symptom burden and risk of recalcitrant disease. A number of non-antibiotic, 'anti-biofilm' treatments exist which show anti-biofilm properties in preclinical studies. There is little evidence evaluating their impact on clinical symptom scores in chronic rhinosinusitis.

METHOD

A systematic review was performed to assess the literature regarding the efficacy of non-steroid, non-antibiotic, anti-biofilm specific topical therapies in the treatment of chronic rhinosinusitis. The primary outcome assessed was change in validated patient reported outcome measures before and after anti-biofilm treatment.

RESULTS

Thirteen studies assessing the effect of anti-biofilm therapies in chronic rhinosinusitis through validated patient-reported outcome measures were included. Seven different anti-biofilm specific therapies for chronic rhinosinusitis were identified. None of the seven anti-biofilm therapies was identified as being confidently efficacious beyond placebo. Only one therapy (intranasal xylitol) showed a statistically significant reduction in symptom scores compared with placebo in more than one trial.

CONCLUSION

Robust evidence supporting the use of various anti-biofilm therapies in chronic rhinosinusitis is lacking. Further high quality, human, in vivo trials studying the effect of anti-biofilm therapies in chronic rhinosinusitis are needed to address the deficiencies of the current evidence base.

Current Perspective on Nasal Delivery Systems for Chronic Rhinosinusitis

Chronic rhinosinusitis is an upper respiratory disease during which topical drug treatment via the nasal cavity is the most actively utilized therapeutic strategy. In addition to steroids, antibiotics, and antifungal agents, which are widely used in clinical practice, research on novel topical agents to improve the bacterial biofilm or mucociliary clearance remains ongoing. Moreover, owing to the complex structure of the nasal cavity, the effects of nasal drug delivery vary depending on factors related to delivery fluid dynamics, including device, volume, and compounds. In this article, we review methods and compounds that have been applied to chronic rhinosinusitis management and introduce recent advances and future perspectives in nasal drug delivery for upper respiratory diseases.

Biopolymers-calcium phosphate antibacterial coating reduces the pathogenicity of internalized bacteria by mesenchymal stromal cells

A multifunctional material system that kills bacteria and drives bone healing is urgently sought to improve bone prosthesis. Herein, the osteoinductive coating made of calcium phosphate/chitosan/hyaluronic acid, named Hybrid, was proposed as an antibacterial substrate for stromal cell adhesion. This Hybrid coating possesses a contact-killing effect reducing by 90% the viability of Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Pseudomonas aeruginosa (P. aeruginosa) strains after 48 h of contact. In addition to the production of immunomodulatory mediators, Wharton's jelly (WJ-SCs), dental pulp (DPSCs) and bone marrow (BM-MSCs) derived stromal cells were able to release antibacterial and antibiofilm agents effective against S. aureus and P. aeruginosa strains, respectively. Studying the effect of the Hybrid coating on the internalization of S. aureus by the stromal cells, in acute-mimicking bone infection, highlighted an increase in the bacteria internalization by DPSCs and BM-MSCs when cultured on the Hybrid coating versus uncoated glass. Despite the internalization, Hybrid coating showed a beneficial effect by reducing the pathogenicity of the internalized bacteria. The formation of biofilm was reduced by at least 50% in comparison to internalized bacteria by stromal cells on uncoated glass. This work opens the route for the development of innovative antibacterial coatings by taking into account the internalization of bacteria by stromal cells.

Hyaluronic acid for the treatment of airway diseases in children: Little evidence for few indications

BACKGROUND

Hyaluronic acid (HA) is major physiological component of the extracellular matrix, which, in its high molecular weight form (HMW-HA) has anti-inflammatory properties. The diffusion of many different medical devices for inhalation therapy containing HA has led to an increase in their prescription, also in children. Here, we systematically review the published evidence on the efficacy and safety of HA for the treatment of upper and lower airway diseases in childhood.

METHODS

Relevant published studies (randomized controlled trials) for the efficacy of HA inhalation in children with upper airways diseases, asthma, cystic fibrosis (CF), and non-CF bronchiectasis were searched in Pubmed, Scopus, and Web of Knowledge databases by combining the adequate Medical Subject Headings terms and keywords, with no limit for the year of publication.

RESULTS

We identified seven relevant publications for upper airways diseases, one for asthma, and five for CF, while we found no clinical trial including children with non-CF bronchiectasis. Meta-analysis was not conducted due to the heterogeneity of the included studies.

CONCLUSIONS

The evidence of HA efficacy in the treatment of the upper and lower airways is still limited in children. Available data suggest that inhaled HMW-HA could be useful in the treatment of recurrent upper respiratory infections and chronic or recurrent inflammation of the middle ear and adenoids as well as of the lower airways in cystic fibrosis in association with hypertonic saline solution. Studies on larger populations and on the different formulations and nebulization methods, especially in pediatric age, are urgently needed.

An alternative to skin graft for superficial surgical defect in oral cancer surgery

Introduction

After surgery for oral cavity cancer, superficial surgical defects are usually covered with a skin graft that can be harvested with different thicknesses depending on the reconstructive need. Despite its popularity and efficacy, this solution has the disadvantage of excessive harvesting times and scarring of the donor site. Other surgeons have proposed the use of bovine pericardium as a reconstructive solution. Its use in otorhinolaryngology especially after oral cavity surgery has never been reported.

Objective

The aim of this manuscript is to present our preliminary experience with the use of a collagen membrane obtained from bovine pericardium in the reconstruction of small and superficial defects after transoral resection of oral cavity tumors.

Methods

A bovine collagen membrane was used to cover surgical defects in 19 consecutive patients undergoing transoral resection of small/superficial oral cancers. Photographs were obtained in the postoperative period to follow the healing process. We analyzed the pro and cons of this tool, recorded data on postoperative chewing-, speech- and taste-related quality of life, and tested the most appropriate settings providing the best reconstructive result.

Results

The bovine collagen membrane allowed us to cover surgical defects of varying size in different oral sites. Shaping and placement proved to be simple. The membrane facilitated physiologic tissue repair: after one month it was completely absorbed and replaced by the patient’s own mucosa. No adverse features were observed in the cohort.

Conclusion

A bovine collagen membrane can represent a fast and easy solution in cases of split-thickness defect. Unlike a skin graft, it is not associated with donor site morbidity and allows the patient’s own mucosa to be restored with a more physiological result.

Hyaluronic acid in otology: Its uses, advantages and drawbacks - A review

OBJECTIVES

Review of the literature for studies involving the use of hyaluronic acid (HA) in otology.

METHODS

Pubmed and OvidMedline were searched using a combination of the following words in different variations: hyaluronic acid, hyaluronate, otolaryngology, otology, ear, tympanic membrane, perforation, tympanostomy, tympanoplasty, myringoplasty, packing, middle ear, cochlea, gene delivery, gene therapy, cochlear implant, hearing loss, meniere, vertigo, otitis and cholesteatoma.

RESULTS

The papers relevant for this review were triaged based on abstracts and titles and were then categorized based on topic/disease entity/procedure. The papers were read and summarized in order to use their findings in this review.

CONCLUSIONS

HA is being recently used as adjuvant therapy for multiple inflammatory conditions and in tissue repair. These immunomodulatory properties and biocompatibility have interested researchers specially in the field of otology for repair, gene delivery, immunomodulation etc. Recent data in the field show optimistic results for the use of HA in several conditions especially tympanic membrane perforations and gene delivery. It also establishes the role of HA as ancillary treatment in many other otologic pathologies. This review presents the most recent findings on the use of HA in otology. The results could be used to guide clinical practice and incite further research based on the presented results of the literature.

Cochlear Implant Surgery: How to Fix Receiver/Stimulator Avoiding Extrusion

Cochlear implant (CI) surgery is generally safe and associated with a limited number of complications, among which the extrusion of the receiver/stimulator (R/S) or the electrode misplacement and migration might require a CI re-implantation. The aim of this pilot study is to describe a new technique to firmly fix the R/S using the Mitek suture anchors system (Depuy Mitek Surgical Products, Inc. Raynham, Massachusetts). We tested two different models and in our experience, the web of suture created with this device can improve the stability of the bond of the R/S to the underlying curved bone surface. So, this system resulted in a less laborious manner keeping low the complication rate.

Topical Steroids in Rhinosinusitis and Intraoperative Bleeding: More Harm Than Good?

The aim of this study was to assess whether the chronic preoperative administration of intranasal corticosteroids (INCs) in chronic rhinosinusitis with/without nasal polyposis (CRSwNP/CRSsNP, respectively) could significantly influence bleeding during functional endoscopic sinus surgery (FESS). We prospectively enrolled 109 patients (56 CRSwNP and 53 CRSsNP) candidate for FESS who underwent clinical evaluation and anamnestic data collection. They were allocated to 2 groups depending on whether or not they were chronic INC users, as declared at their first medical evaluation: chronic "INC users" represented the treated group, while "INC nonusers" formed the control group. Lund-Mackay and American Society of Anesthesiology (ASA) scores, blood loss expressed both in milliliters and using the Boezaart scale, operation time in minutes, pre- and postoperative 22-item Sino Nasal Outcome Scores (SNOT-22) were collected. Each sample underwent histopathological evaluation. The results showed that anamnestic information, Lund-Mackay, and SNOT-22 scores were similar between the 2 groups (P > .05). The average blood loss expressed in milliliters and operative time were slightly, but not significantly, higher in the INC user group, while the Boezaart scores proved significantly higher in the INC users (P = .038). No differences emerged between CRSwNP and CRSsNP within each group in terms of bleeding. The pathologist described common features in the majority (78%) of INC group samples: ectatic venules embedded in a fibrous stroma and hypertrophy of the arterial muscular layer. In our experience, despite the presence of NP, chronic preoperative administration of INCs was associated with increased intraoperative bleeding according the Boezaart scale although objective recordings of blood loss were not statistically different between the INC users and nonusers.

Microbial otitis media: recent advancements in treatment, current challenges and opportunities

Otitis media (OM) is a common disease affecting humans, especially paediatric populations. OM refers to inflammation of the middle ear and can be broadly classified into two types, acute and chronic. Bacterial infection is one of the most common causes of OM. Despite the introduction of vaccines, the incidence of OM remains significantly high worldwide. In this mini-review article, we discuss the recent treatment modalities for OM, such as suspension gel, transcutaneous immunization, and intranasal and transtympanic drug delivery, including therapies that are currently undergoing clinical trials. We provide an overview of how these recent advancements in therapeutic strategies can facilitate the circumvention of current treatment challenges involving preadolescence soft palate dysfunction, biofilm formation, tympanic membrane (ear drum) barrier and the attainment of efficacious drug concentrations in the middle ear. While traditional first-line immunization strategies are generally not very efficacious against biofilms, new technologies that use transdermal or intranasal drug delivery via chitosan-PsaA nanoparticles have shown promising results in experimental animal models of OM. Sustained drug delivery systems such as penta-block copolymer poloxamer 407-polybutylphosphoester (P407-PBP) or poloxamer 407 (e.g. OTO-201, with the brand name 'OTIPRIO') have demonstrated that treatments can be reduced to a single topical application. The emergence of effective new treatment modalities opens up promising new avenues for the treatment of OM that could lead to improved quality of life for many children and their families.

Effect of chitosan combined with hyaluronate on promoting the recovery of postoperative facial nerve regeneration and function in rabbits

To determine better solutions for postoperative nerve functional recovery, the effects of chitosan and hyaluronate on perineural scar formation and neural function recovery were investigated in 40 rabbits. Rabbits were randomized into 4 groups: A (chitosan), B (chitosan + hyaluronate), C (hyaluronate) and D (control). The rabbits underwent the same parotidectomy surgery, but different materials were used to cover the operated nerves. By evaluating specific indicators, including vibrissae motion tests, neural electrophysiological examinations and extraneural examinations, it was revealed that the amplitude of vibrissae motion of all groups had increased 6 weeks after surgery. The recovery of Group B was superior compared with all other groups at 4 and 12 weeks post-surgery; however no significant differences were detected. Group B exhibited a great number of nerve fibers, thicker myelin sheath and greater nerve conduction velocity. In summary, the use of a chitosan conduit combined with sodium hyaluronate gel may prevent perineural scar formation in facial nerves and promote nerve functional recovery.

Recent developments in smart antibacterial surfaces to inhibit biofilm formation and bacterial infections

Since their development over 70 years, antibiotics are still the most effective strategy to treat bacterial biofilms and infections.