Hyaluronic acid. A review of its pharmacology and use as a surgical aid in ophthalmology, and its therapeutic potential in joint disease and wound healing

Potential of natural polysaccharide for ovarian cancer therapy

Ovarian cancer, characterized by high lethality, presents a significant clinical challenge. The standard first-line treatment is surgery and chemotherapy; however, postoperative chemotherapy is often ineffective and associated with severe side effects and the development of drug resistance. Consequently, there is an urgent need for innovative drug delivery strategies to enhance therapeutic efficacy. Natural polysaccharide polymers with high bioactivity have been extensively investigated for use alone or as adjuvants to chemotherapy and radiotherapy, and also for the preparation of efficient delivery systems for ovarian cancer therapy. This paper aims to review recent advances in the application of natural polysaccharides, including hyaluronic acid, chitosan, alginate, and cellulose, in the therapy of ovarian cancer. This paper primarily discusses the anti-tumor properties inherent to these natural polysaccharide polymers and offers a summary of their role in delivery systems used in ovarian cancer therapy.

Influence of buffer on colloidal stability, microstructure, and rheology of cellulose nanocrystals in hyaluronic acid suspensions

Hyaluronic acid (HA) is a natural biopolymer found in various human tissues, while cellulose nanocrystals (CNCs) extracted from pulp fibers have unique rheological properties and biocompatibility. Due to the superior biomechanical properties of CNC and HA, a CNC-based HA suspension may be useful in biomedical applications. While buffers are an essential constituent of any suspension used for biomedical applications to maintain the desired pH level, they can significantly affect the properties of the suspension, including colloidal stability, microstructure, and rheological characteristics. To our knowledge, this is the first study analyzing the influence of buffer solutions on the suspension characteristics of HA/CNC systems, integrating both theoretical and experimental approaches. The results revealed an alignment between predictions of the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory and results from experiments characterizing a buffer-specific trend in colloidal stability. Suspensions with a higher energy barrier showed higher colloidal stability, with a lower tendency for phase separation and agglomerate formations. The microstructural analysis of CNC tactoids in the suspension revealed the existence of the hedgehog defect when dispersed in different buffer solutions. The defect is predicted to be caused by the pH-dependent protonation and deprotonation of HA. Furthermore, steady shear viscometry showed a microstructural-dependent shear viscosity trend, which, in turn, depends on the buffer solution. The study provides novel insights into the microstructural and bulk properties of HA and CNC suspensions in various buffer solutions. The results highlight the importance of solvent choice in tailoring the properties of the suspension for specific biomedical applications. These findings may be helpful in formulating HA and CNC suspensions for different biomedical applications, including drug delivery systems and viscosupplement injections.

3D-Printed Polymeric Biomaterials for Health Applications

3D printing, also known as additive manufacturing, holds immense potential for rapid prototyping and customized production of functional health-related devices. With advancements in polymer chemistry and biomedical engineering, polymeric biomaterials have become integral to 3D-printed biomedical applications. However, there still exists a bottleneck in the compatibility of polymeric biomaterials with different 3D printing methods, as well as intrinsic challenges such as limited printing resolution and rates. Therefore, this review aims to introduce the current state-of-the-art in 3D-printed functional polymeric health-related devices. It begins with an overview of the landscape of 3D printing techniques, followed by an examination of commonly used polymeric biomaterials. Subsequently, examples of 3D-printed biomedical devices are provided and classified into categories such as biosensors, bioactuators, soft robotics, energy storage systems, self-powered devices, and data science in bioplotting. The emphasis is on exploring the current capabilities of 3D printing in manufacturing polymeric biomaterials into desired geometries that facilitate device functionality and studying the reasons for material choice. Finally, an outlook with challenges and possible improvements in the near future is presented, projecting the contribution of general 3D printing and polymeric biomaterials in the field of healthcare.

A case of bone resorption in the mentum caused by hyaluronic acid filler in a patient with skeletal Class II jaw deformity

Key Clinical Message

Chin augmentation by hyaluronic acid filler injection rarely causes abnormal bone resorption in the mentum. Thus, when taking the history of a patient with jaw deformity, it is imperative to check the history of treatment of the mentum.

Abstract

Hyaluronic acid (HA) filler injection is a common procedure in nonsurgical cosmetic chin augmentation. Due to its high biocompatibility and simple injection technique, HA filler injection is a popular procedure. However, adverse events such as allergic reactions and foreign body reactions have been reported in some cases. In this study, we report a case of skeletal Class II jaw deformity in which bone resorption was observed in the mentum after HA filler injection. The purpose of this study is to discuss the indications for HA filler injection in skeletal Class II cases that require orthognathic surgery. The patient was a 30-year-old woman. To improve retrusion of the mentum, she has been receiving HA filler injections in the mentum three times every 6 months in the cosmetic surgery clinic since 2015. However, the retrusion of the mentum did not improve, which prompted here to visit the orthodontic clinic. Radiographs and CT revealed bowl-shaped bone resorption surrounding the foreign bodies in the mentum. She was diagnosed with maxillary protrusion, vertical maxillary excess, mandibular retrusion, and bilateral condylar resorption. Bimaxillary orthognathic surgery (BOGS) and removal of residual HA fillers were planned after completion of the preoperative orthodontic treatment. After BOGS, the foreign bodies were completely removed, and the resorption cavities were filled with excess bone segments from the surgical sites. X-ray photoelectron spectroscopy analysis of the foreign bodies suggested the presence of HA. One year after the BOGS, no progression of condylar resorption occurred, and bone healing at the mentum had a good prognosis. Therefore, the patient underwent reduction and advancement genioplasty. She was satisfied with her facial profile and occlusal function. Unexpected bone resorption in the mentum caused by HA filler injection is often discovered incidentally. Although, patients may feel hesitant to confess their history of treatment of the mentum, it is important to ensure that they are carefully interviewed.

Quaternary ammonium carboxymethyl chitosan composite hydrogel with efficient antibacterial and antioxidant properties for promoting wound healing

Multifunctional hydrogels have been developed to meet the various requirements of wound healing. Herein, an innovative hydrogel (QCMC-HA-PEG) was formed through the Schiff base reaction, composed of quaternary ammonium-modified carboxymethyl chitosan (QCMC), hyaluronic acid (HA), and 8-arms Polyethylene Glycol aldehyde (8-ARM-PEG-CHO). The resulting hydrogels exhibited good mechanical and adhesive properties with improved antibacterial efficacy against both Gram-positive and Gram-negative bacteria compared to CMC hydrogels. QCMC-HA-PEG hydrogels demonstrated remarkable adhesive ability in lap-shear test. Furthermore, the incorporation of MnO2 nanosheets into the hydrogel significantly enhanced its reactive oxygen species (ROS) scavenging and oxygen generation capabilities. Finally, experimental results from a full-thickness skin wound model revealed that the QCMC-HA-PEG@MnO2 hydrogel promoted skin epithelization, collagen deposition, and inflammatory regulation significantly accelerated the wound healing process. Therefore, QCMC-HA-PEG@MnO2 hydrogel could be a promising wound dressing to promote wound healing.

The application of phenylboronic acid pinacol ester functionalized ROS-responsive multifunctional nanoparticles in the treatment of Periodontitis

Periodontitis is an inflammatory disease induced by the complex interactions between the host immune system and the microbiota of dental plaque. Oxidative stress and the inflammatory microenvironment resulting from periodontitis are among the primary factors contributing to the progression of the disease. Additionally, the presence of dental plaque microbiota plays a significant role in affecting the condition. Consequently, treatment strategies for periodontitis should be multi-faceted. In this study, a reactive oxygen species (ROS)-responsive drug delivery system was developed by structurally modifying hyaluronic acid (HA) with phenylboronic acid pinacol ester (PBAP). Curcumin (CUR) was encapsulated in this drug delivery system to form curcumin-loaded nanoparticles (HA@CUR NPs). The release results indicate that CUR can be rapidly released in a ROS environment to reach the concentration required for treatment. In terms of uptake, HA can effectively enhance cellular uptake of NPs because it specifically recognizes CD44 expressed by normal cells. Moreover, HA@CUR NPs not only retained the antimicrobial efficacy of CUR, but also exhibited more pronounced anti-inflammatory and anti-oxidative stress functions both in vivo and in vitro. This provides a good potential drug delivery system for the treatment of periodontitis, and could offer valuable insights for dental therapeutics targeting periodontal diseases.

Gelatin Methacryloyl (GelMA)-Based Biomaterial Inks: Process Science for 3D/4D Printing and Current Status

Tissue engineering for injured tissue replacement and regeneration has been a subject of investigation over the last 30 years, and there has been considerable interest in using additive manufacturing to achieve these goals. Despite such efforts, many key questions remain unanswered, particularly in the area of biomaterial selection for these applications as well as quantitative understanding of the process science. The strategic utilization of biological macromolecules provides a versatile approach to meet diverse requirements in 3D printing, such as printability, buildability, and biocompatibility. These molecules play a pivotal role in both physical and chemical cross-linking processes throughout the biofabrication, contributing significantly to the overall success of the 3D printing process. Among the several bioprintable materials, gelatin methacryloyl (GelMA) has been widely utilized for diverse tissue engineering applications, with some degree of success. In this context, this review will discuss the key bioengineering approaches to identify the gelation and cross-linking strategies that are appropriate to control the rheology, printability, and buildability of biomaterial inks. This review will focus on the GelMA as the structural (scaffold) biomaterial for different tissues and as a potential carrier vehicle for the transport of living cells as well as their maintenance and viability in the physiological system. Recognizing the importance of printability toward shape fidelity and biophysical properties, a major focus in this review has been to discuss the qualitative and quantitative impact of the key factors, including microrheological, viscoelastic, gelation, shear thinning properties of biomaterial inks, and printing parameters, in particular, reference to 3D extrusion printing of GelMA-based biomaterial inks. Specifically, we emphasize the different possibilities to regulate mechanical, swelling, biodegradation, and cellular functionalities of GelMA-based bio(material) inks, by hybridization techniques, including different synthetic and natural biopolymers, inorganic nanofillers, and microcarriers. At the close, the potential possibility of the integration of experimental data sets and artificial intelligence/machine learning approaches is emphasized to predict the printability, shape fidelity, or biophysical properties of GelMA bio(material) inks for clinically relevant tissues.

Research Progress on Injectable Microspheres as New Strategies for the Treatment of Osteoarthritis Through Promotion of Cartilage Repair

Osteoarthritis (OA) is a degenerative disease caused by a variety of factors with joint pain as the main symptom, including fibrosis, chapping, ulcers, and loss of cartilage. Traditional treatment can only delay the progression of OA, and classical delivery system have many side effects. In recent years, microspheres have shown great application prospects in the field of OA treatment. Microspheres can support cells, reproduce the natural tissue microenvironment in vitro and in vivo, and are an efficient delivery system for the release of drugs or biological agents, which can promote cell proliferation, migration, and differentiation. Thus, they have been widely used in cartilage repair and regeneration. In this review, preparation processes, basic materials, and functional characteristics of various microspheres commonly used in OA treatment are systematically reviewed. Then it is introduced surface modification strategies that can improve the biological properties of microspheres and discussed a series of applications of microsphere functionalized scaffolds in OA treatment. Finally, based on bibliometrics research, the research development, future potential, and possible research hotspots of microspheres in the field of OA therapy is systematically and dynamically evaluated. The comprehensive and systematic review will bring new understanding to the field of microsphere treatment of OA.

Progress of polysaccharide-based tissue adhesives

Recently, polymer-based tissue adhesives (TAs) have gained the attention of scientists and industries as alternatives to sutures for sealing and closing wounds or incisions because of their ease of use, low cost, minimal tissue damage, and short application time. However, poor mechanical properties and weak adhesion strength limit the application of TAs, although numerous studies have attempted to develop new TAs with enhanced performance. Therefore, next-generation TAs with improved multifunctional properties are required. In this review, we address the requirements of polymeric TAs, adhesive characteristics, adhesion strength assessment methods, adhesion mechanisms, applications, advantages and disadvantages, and commercial products of polysaccharide (PS)-based TAs, including chitosan (CS), alginate (AL), dextran (DE), and hyaluronic acid (HA). Additionally, future perspectives are discussed.

LncRNA-mediated cartilage homeostasis in osteoarthritis: a narrative review

Osteoarthritis (OA) is a degenerative disease of cartilage that affects the quality of life and has increased in morbidity and mortality in recent years. Cartilage homeostasis and dysregulation are thought to be important mechanisms involved in the development of OA. Many studies suggest that lncRNAs are involved in cartilage homeostasis in OA and that lncRNAs can be used to diagnose or treat OA. Among the existing therapeutic regimens, lncRNAs are involved in drug-and nondrug-mediated therapeutic mechanisms and are expected to improve the mechanism of adverse effects or drug resistance. Moreover, targeted lncRNA therapy may also prevent or treat OA. The purpose of this review is to summarize the links between lncRNAs and cartilage homeostasis in OA. In addition, we review the potential applications of lncRNAs at multiple levels of adjuvant and targeted therapies. This review highlights that targeting lncRNAs may be a novel therapeutic strategy for improving and modulating cartilage homeostasis in OA patients.

Comparative In Vivo Study of Solid-Type Pure Hyaluronic Acid in Thread Form: Safety and Efficacy Compared to Hyaluronic Acid Filler and Polydioxanone Threads

INTRODUCTION

Although various products are commonly used for skin rejuvenation, solid-type hyaluronic acid (HA) as an injectable form has not been researched or utilized. This study aimed to demonstrate the safety and efficacy of solid-type HA in thread form, which differs from the conventional gel-type HA commonly used.

METHOD

Solid-type HA threads, conventional HA fillers, and polydioxanone (PDO) threads were inserted into the dorsal subcutaneous layer of mice. Photographs were taken on days 0, 1, 3, and 7, and on day 7, the samples were harvested for histological analysis. Inflammatory reactions and detection of collagen were confirmed through tissue staining, and real-time PCR was conducted to quantify collagen synthesis.

RESULTS

In the histological analysis, the PDO threads exhibited a greater inflammatory response compared to the HA threads. Masson's trichrome staining revealed a higher degree of collagen synthesis in the HA thread group compared to the HA filler group. While collagen type 1 expression was significantly higher in the PDO thread group than in the HA thread group, the HA thread group showed higher expression levels of collagen type 3. Furthermore, the PDO thread group demonstrated a statistically significant increase in TGF-β1 compared to the HA group.

CONCLUSION

This in vivo study demonstrated the stable application of solid-type pure HA threads and their potential for inducing collagen production, while also yielding a low inflammatory response. The findings highlight the promising applications of solid-type HA in the field of cosmetic dermatology.

NO LEVEL ASSIGNED

This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Hyaluronic acid/tannic acid films for wound healing application

In this study, thin films based on hyaluronic acid (HA) with tannic acid (TA) were investigated in three different weight ratios (80HA/20TA, 50HA/50TA, 20HA/80TA) for their application as materials for wound healing. Surface free energy, as well as their roughness, mechanical properties, water vapor permeability rate, and antioxidant activity were determined. Moreover, their compatibility with blood and osteoblast cells was investigated. The irritation effect caused by hyaluronic acid/tannic acid films was also considered with the use of are constructed human epidermis model. The irritation effect for hyaluronic acid/tannic acid films by the in vitro method was also studied. The low surface free energy, surface roughness, and antioxidant activity presented by the obtained films were examined. All the tested compositions of hyaluronic acid/tannic acid films were hemocompatible, but only films based on 50HA/50TA were fully cytocompatible. Regarding the potential implantation, all the films except 80HA/20TA showed appropriate mechanical properties. The specimens did not exert the irritation effect during the studies involving reconstructed human epidermis.

Stimulus-Responsive Hydrogels as Drug Delivery Systems for Inflammation Targeted Therapy

Deregulated inflammations induced by various factors are one of the most common diseases in people's daily life, while severe inflammation can even lead to death. Thus, the efficient treatment of inflammation has always been the hot topic in the research of medicine. In the past decades, as a potential biomaterial, stimuli-responsive hydrogels have been a focus of attention for the inflammation treatment due to their excellent biocompatibility and design flexibility. Recently, thanks to the rapid development of nanotechnology and material science, more and more efforts have been made to develop safer, more personal and more effective hydrogels for the therapy of some frequent but tough inflammations such as sepsis, rheumatoid arthritis, osteoarthritis, periodontitis, and ulcerative colitis. Herein, from recent studies and articles, the conventional and emerging hydrogels in the delivery of anti-inflammatory drugs and the therapy for various inflammations are summarized. And their prospects of clinical translation and future development are also discussed in further detail.

Utilization of experimental design in the formulation and optimization of hyaluronic acid-based nanoemulgel loaded with a turmeric-curry leaf oil nanoemulsion for gingivitis

Numerous problems affect oral health, and intensive research is focused on essential oil-based nanoemulsions that might treat prevent or these problems. Nanoemulsions are delivery systems that enhance the distribution and solubility of lipid medications to targeted locations. Turmeric (Tur)- and curry leaf oil (CrO)-based nanoemulsions (CrO-Tur-self-nanoemulsifying drug delivery systems [SNEDDS]) were developed with the goal of improving oral health and preventing or treating gingivitis. They could be valuable because of their antibacterial and anti-inflammatory capabilities. CrO-Tur-SNEDDS formulations were produced using the response surface Box-Behnken design with different concentrations of CrO (120, 180, and 250 mg), Tur (20, 35, and 50 mg), and Smix 2:1 (400, 500, and 600 mg). The optimized formulation had a bacterial growth inhibition zone of up to 20 mm, droplet size of less than 140 nm, drug-loading efficiency of 93%, and IL-6 serum levels of between 950 ± 10 and 3000 ± 25 U/ml. The optimal formulation, which contained 240 mg of CrO, 42.5 mg of Tur, and 600 mg of Smix 2:1, was created using the acceptable design. Additionally, the best CrO-Tur-SNEDDS formulation was incorporated into a hyaluronic acid gel, and thereafter it had improved ex-vivo transbuccal permeability, sustained in-vitro release of Tur, and large bacterial growth suppression zones. The optimal formulation loaded into an emulgel had lower levels of IL-6 in the serum than the other formulations evaluated in rats. Therefore, this investigation showed that a CrO-Tur-SNEDDS could provide strong protection against gingivitis caused by microbial infections.

Tapping on the Potential of Hyaluronic Acid: from Production to Application

The manufacture, purification, and applications of hyaluronic acid (HA) are discussed in this article. Concerning the growing need for affordable, high-quality HA, it is essential to consider diverse production techniques using renewable resources that pose little risk of cross-contamination. Many microorganisms can now be used to produce HA without limiting the availability of raw materials and in an environmentally friendly manner. The production of HA has been associated with Streptococci A and C, explicitly S. zooepidemicus and S. equi. Different fermentation techniques, including the continuous, batch, fed-batch, and repeated batch culture, have been explored to increase the formation of HA, particularly from S. zooepidemicus. The topic of current interest also involves a complex broth rich in metabolites and residual substrates, intensifying downstream processes to achieve high recovery rates and purity. Although there are already established methods for commercial HA production, the anticipated growth in trade and the diversification of application opportunities necessitate the development of new procedures to produce HA with escalated productivity, specified molecular weights, and purity. In this report, we have enacted the advancement of HA technical research by analyzing bacterial biomanufacturing elements, upstream and downstream methodologies, and commercial-scale HA scenarios.

Hydrogels as Scaffolds in Bone-Related Tissue Engineering and Regeneration

Several years have passed since the medical and scientific communities leaned toward tissue engineering as the most promising field to aid bone diseases and defects resulting from degenerative conditions or trauma. Owing to their histocompatibility and non-immunogenicity, bone grafts, precisely autografts, have long been the gold standard in bone tissue therapies. However, due to issues associated with grafting, especially the surgical risks and soaring prices of the procedures, alternatives are being extensively sought and researched. Fibrous and non-fibrous materials, synthetic substitutes, or cell-based products are just a few examples of research directions explored as potential solutions. A very promising subgroup of these replacements involves hydrogels. Biomaterials resembling the bone extracellular matrix and therefore acting as 3D scaffolds, providing the appropriate mechanical support and basis for cell growth and tissue regeneration. Additional possibility of using various stimuli in the form of growth factors, cells, etc., within the hydrogel structure, extends their use as bioactive agent delivery platforms and acts in favor of their further directed development. The aim of this review is to bring the reader closer to the fascinating subject of hydrogel scaffolds and present the potential of these materials, applied in bone and cartilage tissue engineering and regeneration.

The Era of Biomaterials: Smart Implants?

Conditions, accidents, and aging processes have brought with them the need to develop implants with higher technology that allow not only the replacement of missing tissue but also the formation of tissue and the recovery of its function. The development of implants is due to advances in different areas such as molecular-biochemistry (which allows the understanding of the molecular/cellular processes during tissue repair), materials engineering, tissue regeneration (which has contributed advances in the knowledge of the properties of the materials used for their manufacture), and the so-called intelligent biomaterials (which promote tissue regeneration through inductive effects of cell signaling in response to stimuli from the microenvironment to generate adhesion, migration, and cell differentiation processes). The implants currently used are combinations of biopolymers with properties that allow the formation of scaffolds with the capacity to mimic the characteristics of the tissue to be repaired. This review describes the advances of intelligent biomaterials in implants applied in different dental and orthopedic problems; by means of these advances, it is expected to overcome limitations such as additional surgeries, rejections and infections in implants, implant duration, pain mitigation, and mainly, tissue regeneration.

Accuracy of Intraarticular Injections: Blind vs. Image Guided Techniques-A Review of Literature

Intra-articular injections are widely used for diagnostic and therapeutic purposes of joint pathologies throughout the body. These injections can be performed blind by utilizing anatomical landmarks or with the use of imaging modalities to directly visualize the joint space during injections. This review of the literature aims to comprehensively identify differences in the accuracy of intra-articular injections via palpation vs. image guidance in the most commonly injected joints in the upper and lower extremities. To our knowledge, there are no such comprehensive reviews available. A narrative literature review was performed using PubMed and Google Scholar databases to identify studies focusing on the accuracy of blind or image-guided intra-articular injections for each joint. A total of 75 articles was included in this review, with blind and image-guided strategies being discussed for the most commonly injected joints of the upper and lower extremities. Varying ranges of accuracy with blind and image-guided modalities were found throughout the literature, though an improvement in accuracy was seen in nearly all joints when using image guidance. Differences are pronounced, particularly in deep joints such as the hip or in the small joints such as those in the hand or foot. Image guidance is a useful adjunct for most intra-articular injections, if available. Though there is an increase in accuracy in nearly all joints, minor differences in accuracy seen in large, easily accessed joints, such as the knee, may not warrant image guidance.

Dual-bioactive molecules loaded aligned core-shell microfibers for tendon tissue engineering

Development of a controlled delivery ultrafine fibrous system with two bioactive molecules is required to stimulate tendon healing in different phase. In this study, we used emulsion stable jet electrospinning to fabricate aligned poly(L-lactic acid) (PLLA) based ultrafine fibers with two small bioactive molecules of L-Arginine (Arg) and low molecular weight hyaluronic acid (HA). The results demonstrated that the aligned Arg/HA/PLLA microfibrous scaffold showed core-shell structure and allowed sequential release of Arg and HA due to their different electric charge. The scaffold also showed enhanced hydrophilicity, cell migration, spread and proliferation. Using an Achilles tendon repair model in rats, we demonstrated that this novel fibrous scaffold can prevent adhesion and promote tendon regeneration. Additionally, two p53 and ER-α-mediated signalling pathways were described as the probable main path of synergistic effects of the novel scaffold on tendon generation. Thus, this study may provide an important strategy for developing biofunctional and biomimetic tendon scaffolds.

Cyclodextrin-enabled nepafenac eye drops with improved absorption open a new therapeutic window

Nepafenac is a highly effective NSAID used for treating postoperative ocular inflammation and pain after cataract surgery and its advantage over conventional topical NSAIDs has been proved many times. However, Nevanac® is a suspension eye drop, which clearly lacks patient compliance causing irritation, blurred vision, foreign body sensation along with problematic dosage due to its sticky, inhomogeneous consistence. In this study, nepafenac containing eye drops were prepared using hydroxypropyl-β-cyclodextrin to ensure complete dissolution of nepafenac, sodium hyaluronate to provide mucoadhesion and adequate viscosity and a preservative-free officinal formula, Oculogutta Carbomerae containing carbomer (just like Nevanac®), therefore providing a similar base for the new formulations. According to an experimental design, 11 formulations were tested in vitro including two reference formulations by measuring their viscosity, mucoadhesion, drug release and corneal permeability. Finally, two formulations were found promising and investigated further on porcine eyes ex vivo and corneal distribution of nepafenac was determined by RAMAN mapping. The results showed that one formulation possessed better bioavailability ex vivo than Nevanac® 0.1 % suspension, while the other formulation containing only 60 % of the original dose were ex vivo equivalent with Nevanac® opening the way to nepafenac-containing eye drops with better patient compliance in the future.

Current advancements in bio-ink technology for cartilage and bone tissue engineering

In tissue engineering, the fate of a particular organ/tissue regeneration and repair mainly depends on three pillars - 3D architecture, cells used, and stimulus provided. 3D cell supportive structure development is one of the crucial pillars necessary for defining organ/tissue geometry and shape. In recent years, the advancements in 3D bio-printing (additive manufacturing) made it possible to develop very precise 3D architectures with the help of industrial software like Computer-Aided Design (CAD). The main requirement for the 3D printing process is the bio-ink, which can act as a source for cell support, proliferation, drug (growth factors, stimulators) delivery, and organ/tissue shape. The selection of the bio-ink depends upon the type of 3D tissue of interest. Printing tissues like bone and cartilage is always challenging because it is difficult to find printable biomaterial that can act as bio-ink and mimic the strength of the natural bone and cartilage tissues. This review describes different biomaterials used to develop bio-inks with different processing variables and cell-seeding densities for bone and cartilage 3D printing applications. The review also discusses the advantages, limitations, and cell bio-ink compatibility in each biomaterial section. The emphasis is given to bio-inks reported for 3D printing cartilage and bone and their applications in orthopedics and orthodontists. The critical/important performance and the architectural morphology requirements of desired bone and cartilage bio-inks were compiled in summary.

Characterization of the Molecular Weight of Hyaluronan in Eye Products Using a Novel Method of Size Exclusion High-Pressure Liquid Chromatography

Purpose

Hyaluronan (HA) exists in two forms, high molecular weight HA (HMWHA) and low molecular weight HA (LMWHA), which have distinct physiological functions. Therefore it is imperative to know the form of HA within pharmaceutical products, including eye products. This study developed an accurate, sensitive, and quantitative method to characterize the form of HA in eye products. Thereafter, the effects of the HA-containing eye products on corneal wound healing were investigated.

Methods

The MW distributions and concentrations of HA in over the counter eye products were determined by size exclusion chromatography (SEC) high-pressure liquid chromatography (HPLC). The effects of the eye products containing HA on corneal wound healing were characterized both in vitro and in vivo using the scratch assay and the debridement wound model, respectively.

Results

The concentrations and MWs of HA were successfully determined within a range of 0.014 to 0.25 mg/mL using SEC HPLC. The concentrations of HA in the ophthalmic products varied from 0.14 to 4.0 mg/mL and the MWs varied from ∼100 kDa to >2500 kDa. All but one HA-containing eye product had an inhibitory effect on corneal wound healing, whereas pure HA promoted corneal wound healing.

Conclusions

A novel SEC-HPLC method was developed for quantifying and characterizing the MW of HA in eye products. Although HA promoted corneal wound healing, HA-containing eye products inhibited corneal wound healing, likely caused by preservatives.

Translational Relevance

SEC-HPLC could be implemented as a routine method for determining the form of HA in commercially available ophthalmic products.

Different molecular weights of hyaluronan research in knee osteoarthritis: A state-of-the-art review

Osteoarthritis (OA), the most common form of arthritis, is characterized by progressive cartilage destruction, concomitant adaptive osteogenesis, and loss of joint function. The progression of OA with aging is associated with a decrease in native hyaluronan (HA, hyaluronate or hyaluronic acid) with a high molecular weight (HMW) in synovial fluid and a subsequent increase in lower MW HA and fragments. As HMW HA possesses numerous biochemical and biological properties, we review new molecular insights into the potential of HA to modify OA processes. Different MWs in the formulation of products appear to have varying effects on knee OA (KOA) pain relief, improved function, and postponing surgery. In addition to the safety profile, more evidence indicates that intraarticular (IA) HA administration may be an effective option to treat KOA, with a particular emphasis on the use of HA with fewer injections of higher MW, including potential applications of HA of very HMW. We also analyzed published systemic reviews and meta-analyses of IA HA in treating KOA in order to discuss their conclusions and consensus statements. According to its MW, HA may offer a simple way to refine therapeutic information in selective KOA.

Microbial Hyaluronic Acid Production: A Review

Microbial production of hyaluronic acid (HA) is an area of research that has been gaining attention in recent years due to the increasing demand for this biopolymer for several industrial applications. Hyaluronic acid is a linear, non-sulfated glycosaminoglycan that is widely distributed in nature and is mainly composed of repeating units of N-acetylglucosamine and glucuronic acid. It has a wide and unique range of properties such as viscoelasticity, lubrication, and hydration, which makes it an attractive material for several industrial applications such as cosmetics, pharmaceuticals, and medical devices. This review presents and discusses the available fermentation strategies to produce hyaluronic acid.

Do we miss rare adverse events induced by COVID-19 vaccination?

Although severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has caused many complications, the invention of coronavirus disease 2019 (COVID-19) vaccines has also brought about several adverse events, from common side effects to unexpected and rare ones. Common vaccine-related adverse reactions manifest locally or systematically following any vaccine, including COVID-19 vaccines. Specific side effects, known as adverse events of particular interest (AESI), are unusual and need more evaluation. Here, we discuss some of the most critical rare adverse events of COVID-19 vaccines.

Supramolecular Binding with Lectins: A New Route for Non-Covalent Functionalization of Polysaccharide Matrices

The chemical functionalization of polysaccharides to obtain functional materials has been of great interest in the last decades. This traditional synthetic approach has drawbacks, such as changing the crystallinity of the material or altering its morphology or texture. These modifications are crucial when a biogenic matrix is exploited for its hierarchical structure. In this work, the use of lectins and carbohydrate-binding proteins as supramolecular linkers for polysaccharide functionalization is proposed. As proof of concept, a deproteinized squid pen, a hierarchically-organized β-chitin matrix, was functionalized using a dye (FITC) labeled lectin; the lectin used was the wheat germ agglutinin (WGA). It has been observed that the binding of this functionalized protein homogenously introduces a new property (fluorescence) into the β-chitin matrix without altering its crystallographic and hierarchical structure. The supramolecular functionalization of polysaccharides with protein/lectin molecules opens up new routes for the chemical modification of polysaccharides. This novel approach can be of interest in various scientific fields, overcoming the synthetic limits that have hitherto hindered the technological exploitation of polysaccharides-based materials.

Hyaluronic Acid Filler Incidentally Found During Mohs Micrographic Surgery: Observations in 36 Patients Regarding Skin Depth, Degradation Size, and Estimated Persistence Time

BACKGROUND

Although its clinical effect is reported to last up to 2 years, how long hyaluronic acid filler (HAF) histologically persists in the skin is unknown.

OBJECTIVE

To determine the approximate persistence time of HAF in the skin and to correlate persistence time with HAF histological appearance, size, depth, and location.

METHODS

Retrospective review of patient data and available frozen sections from 2003 to 2021 in which HAF was identified in 36 Mohs micrographic surgery patients.

RESULTS

Incidental HAF histologically persisted in the skin for as long as 10.75 years in 1 patient and 3 years or more in 36.8% (7/19) of the patients who remembered the time of implantation. HAF is more apparent in frozen sections stained with toluidine blue than those stained with hematoxylin and eosin. Although HAF volume tended to be less with time, fragmentation was present both early at 3 months and at 3 years or more. There was no correlation of persistence time with anatomic location or depth. In 90.3% of the cases (28/31), HAF was located in the subcutaneous fat. There was no granulomatous or giant cell response at any time period.

CONCLUSION

Hyaluronic acid filler may be seen histopathologically in the skin, usually in the subcutaneous fat, up to 10.75 years after implantation.

Electrospun PCL Scaffolds as Drug Carrier for Corneal Wound Dressing Using Layer-by-Layer Coating of Hyaluronic Acid and Heparin

Due to its ability to reduce scarring and inflammation, human amniotic membrane is a widely used graft for wound dressings after corneal surgery. To overcome donor dependency and biological variances in the donor tissue, artificial nanofibrous grafts acting as drug carrier systems are promising substitutes. Electrospun nanofibrous scaffolds seem to be an appropriate approach as they offer the properties of permeable scaffolds with a high specific surface, the latter one depending on the fiber diameter. Electrospun scaffolds with fiber diameter of 35 nm, 113 nm, 167 nm and 549 nm were manufactured and coated by the layer-by-layer (LbL) technology with either hyaluronic acid or heparin for enhanced regeneration of corneal tissue after surgery. Studies on drug loading capacity and release kinetics defined a lower limit for nanofibrous scaffolds for effective drug loading. Additionally, scaffold characteristics and resulting mechanical properties from the application-oriented characterization of suture pullout from suture retention tests were examined. Finally, scaffolds consisting of nanofibers with a mean fiber diameter of 113 nm were identified as the best-performing scaffolds, concerning drug loading efficiency and resistance against suture pullout.

The Food-Materials Nexus: Next Generation Bioplastics and Advanced Materials from Agri-Food Residues

The most recent strategies available for upcycling agri-food losses and waste (FLW) into functional bioplastics and advanced materials are reviewed and the valorization of food residuals are put in perspective, adding to the water-food-energy nexus. Low value or underutilized biomass, biocolloids, water-soluble biopolymers, polymerizable monomers, and nutrients are introduced as feasible building blocks for biotechnological conversion into bioplastics. The latter are demonstrated for their incorporation in multifunctional packaging, biomedical devices, sensors, actuators, and energy conversion and storage devices, contributing to the valorization efforts within the future circular bioeconomy. Strategies are introduced to effectively synthesize, deconstruct and reassemble or engineer FLW-derived monomeric, polymeric, and colloidal building blocks. Multifunctional bioplastics are introduced considering the structural, chemical, physical as well as the accessibility of FLW precursors. Processing techniques are analyzed within the fields of polymer chemistry and physics. The prospects of FLW streams and biomass surplus, considering their availability, interactions with water and thermal stability, are critically discussed in a near-future scenario that is expected to lead to next-generation bioplastics and advanced materials.

Hyaluronic acid-fibrin hydrogels show improved mechanical stability in dermo-epidermal skin substitutes

Human plasma-derived bilayered skin substitutes have been successfully used by our group in different skin tissue engineering applications. However, several issues associated with their poor mechanical properties were observed, and they often resulted in rapid contraction and degradation. In this sense, hydrogels composed of plasma-derived fibrin and thiolated-hyaluronic acid (HA-SH, 0.05-0.2% w/v) crosslinked with poly(ethylene glycol) diacrylate (PEGDA, 2:1, 6:1, 10:1 and 14:1 mol of thiol to moles of acrylate) were developed to reduce the shrinking rates and enhance the mechanical properties of the plasma-derived matrices. Plasma/HA-SH-PEGDA hydrogels showed a decrease in the contraction behaviour ranging from 5% to 25% and an increase in Young's modulus. Furthermore, the results showed that a minimal amount of the added HA-SH was able to escape the plasma/HA-SH-PEGDA hydrogels after incubation in PBS. The results showed that the increase in rigidity of the matrices as well as the absence of adhesion cellular moieties in the second network of HA-SH/PEGDA, resulted in a decrease in contraction in the presence of the encapsulated primary human fibroblasts (hFBs), which may have been related to an overall decrease in proliferation of hFBs found for all hydrogels after 7 days with respect to the plasma control. The metabolic activity of hFB returned to the control levels at 14 days except for the 2:1 PEGDA crosslinking ratio. The metabolic activity of primary human keratinocytes (hKCs) seeded on the hydrogels showed a decrease when high amounts of HA-SH and PEGDA crosslinker were incorporated. Organotypic skins formed in vitro after 21 days with plasma/HA-SH-PEGDA hydrogels with an HA content of 0.05% w/v and a 2:1 crosslinking ratio were up to three times thicker than the plasma controls, evidencing a reduction in contraction, while they also showed better and more homogeneous keratin 10 (K10) expression in the supra-basal layer of the epidermis. Furthermore, filaggrin expression showed the formation of an enhanced stratum corneum for the constructs containing HA. These promising results indicate the potential of using these biomimetic hydrogels as in vitro skin models for pharmaceutical products and cosmetics and future work will elucidate their potential functionality for clinical treatment.

Optimization of Lyophilized Hyperacute Serum (HAS) as a Regenerative Therapeutic in Osteoarthritis

Hyperacute serum (HAS) is a blood derivative product that promotes the proliferation of various cell types and controls inflammation in vitro. The aim of this study is to investigate the regenerative potential of different formulations of HAS, including lyophilized and hyaluronic acid combined versions, to obtain a stable and standardized therapeutic in osteoarthritis (OA), which may be able to overcome the variability limitations of platelet-rich plasma (PRP). Primary human osteoarthritic chondrocytes were used for testing cellular viability and gene expression of OA-related genes. Moreover, a co-culture of human explants of cartilage, bone and synovium under inflammatory conditions was used for investigating the inflammatory control capacities of the different therapeutics. In this study, one formulation of lyophilized HAS achieved the high cell viability rates of liquid HAS and PRP. Gene expression analysis showed that HAS induced higher Col1a1 expression than PRP. Cytokine quantification from supernatant fluids revealed that HAS treatment of inflamed co-cultures significantly reduced levels of IL-5, IL-15, IL-2, TNFα, IL-7 and IL-12. To conclude, lyophilized HAS is a stable and standardized therapeutic with high potential in joint regeneration.

Comparison of wash-out properties after use of the vital dye trypan blue in the form of an ophthalmic dye and bound in a sodium hyaluronate by Raman spectroscopy

PURPOSE

In cataract surgery, viscoelastics protect the corneal endothelium against phacoenergetic and mechanical damage and ensure anterior chamber stability. Vital dyes (trypan blue) are effective aids in anterior segment surgery, especially in challenging cases, but may lead to cytotoxic reactions depending on concentration and dose. A complete removal of the dye is therefore of great importance. Recently, a new viscoelastic colored with Trypan blue (Pe-Ha-Blue®PLUS) was introduced to increase the safety of ophthalmological procedures. The aim of the present work was to determine the residual amount of the dye Trypan Blue that remains on a slide during the routine application of two commercial products (Trypan Blue dye Vision Blue® and Pe-Ha-Blue®PLUS) by Raman spectroscopy.

MATERIALS AND METHODS

For both products, a test sample (after application of the substance, the slides were flushed according to the clinical procedure) and a reference sample (the substances remained on the slide) were imaged using a Raman spectroscope (LabRam 800 HR spectrometer (Horiba Jobin Yvon GmbH, Bensheim, Germany)) and then analyzed.

RESULTS

The remaining residues of the reference samples of both substances were clearly detected by the spectroscopy measurement. In the mean spectrum of the Vision Blue® test specimen, the Raman bands of Trypan blue were clearly visible at a Raman shift of 1200-1600 cm-1, indicating residues on the test specimen. The test sample of Pe-Ha-Blue®PLUS did not show any Raman bands in the typical Trypan blue Raman shift.

CONCLUSIONS

The results of our in-silico experiment showed that a drop of a combination of a vital dye with a viscoelastic could be washed-out more easily with BSS compared to a dye itself without viscoelastics. This suggests that at least in an in silico experiment the removal of both, the viscoelastics and the TB is easier compared to the removal of the TB alone. Further in-vitro experiment in pig cadaver eyes are planned to prove this washout effect. If this concept can be demonstrated, this could further increase the safety of dye-assisted ophthalmic procedures.

Filler Migration to the Orbit

BACKGROUND

Dermal filler injections continue to grow in popularity as a method of facial rejuvenation. This increase in the number of injections performed has resulted in an increasing number of types of filler-related complications.

OBJECTIVES

We report a series of cases where dermal filler injected in the face migrated to the orbit. Treatment methods and possible mechanisms of this newly reported complication are discussed.

METHODS

A retrospective, multicenter analysis was performed on patients with dermal filler migration to the orbit after facial filler injections.

RESULTS

Seven patients (6 females, 1 male; age range, 42-67 years) presented with orbital symptoms after filler injection and were subsequently found to have dermal filler in the orbit. Four out of 7 patients underwent orbitotomy surgery, 1 patient underwent lacrimal surgery, 1 patient had strabismus surgery, and 1 patient was treated with hyalurodinase injections. All patients have remained stable postoperatively.

CONCLUSIONS

Orbital complications secondary to migrated filler may occur long after the initial procedure. Because the site of the complication is distant from the injection site, patients and physicians may not immediately make the connection. Furthermore, this may lead to unnecessary examinations and a delay in diagnosis while looking for standard orbital masses. Dermal fillers should therefore be considered in the differential diagnosis of patients presenting with new-onset orbital masses.

LEVEL OF EVIDENCE: 4

Hyaluronic Acid Reduces Fibrosis in a Rabbit Model of Urethral Anastomosis

INTRODUCTION

Urethral stricture caused by fibrosis is a common medical condition, but top-line therapy for this pathology has a high recurrence rate. This study aimed to determine the efficacy of hyaluronic acid (HA) treatment in preventing the development of fibrosis in a rabbit model of urethral anastomosis.

MATERIALS AND METHODS

This experimental study involved 20 rabbits. HA (0.5 mL, 25 μg/mL) was applied in the experimental group (n = 10) during an experimental urethral anastomosis, and sterile saline (0.9%) solution was applied in the control group (n = 10). Animals underwent reoperation 12 weeks later for urethral resection. Fibrosis, inflammation, and urethral diameter were measured by two blinded pathologists at the site of the anastomosis.

RESULTS

The amount of inflammatory infiltrate was similar in both groups. The thicknesses of the collagen fiber band were 275.9 ± 62.3 and 373.4 ± 44.3 μm in the study and control groups (p = 0.001), respectively, and the urethral lumen diameters at the anastomosis site at follow-up were 2575 ± 167 and 2382 ± 214 μm, respectively (p = 0.04).

CONCLUSION

HA treatment reduced fibrosis at the anastomosis site during this experiment; we suggest further research to corroborate its efficacy in the treatment of urethral stricture.

Wide-field endoscopic submucosal dissection for the treatment of Barrett's esophagus neoplasia

Background and study aims  Implementation of endoscopic submucosal dissection (ESD) for the treatment of Barrett's esophagus neoplasia (BEN) has been hampered by high rates of positive margins and complications. Dissection with wider margins was proposed to overcome these problems, but was never tested. We aim to compare Wide-Field ESD (WF-ESD) with conventional ESD (C-ESD) for treatment of BEN. Patients and methods  This was a cohort study of all ESDs performed in our center during 2011 to 2018. C-ESD was the only technique used before 2014, with WF-ESD used beginning in 2014. In WF-ESD marking was performed 10 mm from the tumor margin compared to 5 mm with C-E. Results  ESD was performed in 90 cases, corresponding to 74 patients, 84 % male, median age 69. Of these, 22 were C-ESD (24 %) and 68 were WF-ESD (76 %). The en bloc resection rate was 95 vs 100 % (ns), the positive lateral margin rate was 23 % vs 3 % ( P  < 0.01), the R0 rate was 73 % vs 90 %, and the curative resection rate was 59 % vs 76 % in the C-ESD and WF-ESD groups, respectively, (both P  > 0.05). The procedure speed was 4.4 and 2.3 (min/mm) in the C-ESD and WF-ESD groups ( P  < 0.01), respectively. WF-ESD was associated with less post-operative strictures, 6 % vs 27 % ( P  = 0.01), with no local recurrence but no significantly reduced risk of metachronous recurrence (Hazard Ratio = 0.46, 95 %CI = 0.14-1.46), during a follow-up of 13.4 and 9.4 months in the C-ESD and WF-ESD cohorts, respectively. Conclusions  WF-ESD is associated with a reduction in positive lateral margins, faster dissection, and lower stricture rates. Further prospective, multicenter studies are warranted to evaluate its role in clinical practice.

β-Ionone Attenuates Dexamethasone-Induced Suppression of Collagen and Hyaluronic Acid Synthesis in Human Dermal Fibroblasts

Stress is a major contributing factor of skin aging, which is clinically characterized by wrinkles, loss of elasticity, and dryness. In particular, glucocorticoids are generally considered key hormones for promoting stress-induced skin aging through binding to glucocorticoid receptors (GRs). In this work, we aimed to investigate whether β-ionone (a compound occurring in various foods such as carrots and almonds) attenuates dexamethasone-induced suppression of collagen and hyaluronic acid synthesis in human dermal fibroblasts, and to explore the mechanisms involved. We found that β-ionone promoted collagen production dose-dependently and increased mRNA expression levels, including collagen type I α 1 chain (COL1A1) and COL1A2 in dexamethasone-treated human dermal fibroblasts. It also raised hyaluronic acid synthase mRNA expression and hyaluronic acid levels. Notably, β-ionone inhibited cortisol binding to GR, subsequent dexamethasone-induced GR signaling, and the expression of several GR target genes. Our results reveal the strong potential of β-ionone for preventing stress-induced skin aging and suggest that its effects are related to the inhibition of GR signaling in human dermal fibroblasts.

The Use of Biologics for Hip Preservation

PURPOSE OF REVIEW

A wide array of nonoperative modalities to treat hip pain are aimed at restoring and maintaining the structural and physiologic characteristics of the joint. The purpose of this review is to describe the current understanding of biologics in hip pathology by providing an evidence-based overview of treatment modalities available for orthopedic surgeons.

RECENT FINDINGS

The use of biologics as a primary treatment or adjunct to traditional management has shown encouraging results for the treatment of hip pain. Studies have demonstrated safety with minimal complications when using platelet rich plasma, hyaluronic acid, or stem cells to treat hip pain caused by osteoarthritis, femoroacetabular impingement syndrome, tendinopathy, or osteonecrosis of the femoral head. Several studies have been able to demonstrate meaningful clinical results that can improve treatment standards for hip pain; however, more work must be performed to better delineate the appropriate protocols, indications, and limitations of each modality. Recent advances have inspired renewed interest in biologics for patients with hip pain. We present a concise review of platelet rich plasma, hyaluronic acid, stem cells, and matrix metalloprotease inhibitors and their applicability to hip preservation surgery.

Polymeric Tissue Adhesives

Polymeric tissue adhesives provide versatile materials for wound management and are widely used in a variety of medical settings ranging from minor to life-threatening tissue injuries. Compared to the traditional methods of wound closure (i.e., suturing and stapling), they are relatively easy to use, enable rapid application, and introduce minimal tissue damage. Furthermore, they can act as hemostats to control bleeding and provide a tissue-healing environment at the wound site. Despite their numerous current applications, tissue adhesives still face several limitations and unresolved challenges (e.g., weak adhesion strength and poor mechanical properties) that limit their use, leaving ample room for future improvements. Successful development of next-generation adhesives will likely require a holistic understanding of the chemical and physical properties of the tissue-adhesive interface, fundamental mechanisms of tissue adhesion, and requirements for specific clinical applications. In this review, we discuss a set of rational guidelines for design of adhesives, recent progress in the field along with examples of commercially available adhesives and those under development, tissue-specific considerations, and finally potential functions for future adhesives. Advances in tissue adhesives will open new avenues for wound care and potentially provide potent therapeutics for various medical applications.

Polymeric Hydrogel Systems as Emerging Biomaterial Platforms to Enable Hemostasis and Wound Healing

Broad interest in developing new hemostatic technologies arises from unmet needs in mitigating uncontrolled hemorrhage in emergency, surgical, and battlefield settings. Although a variety of hemostats, sealants, and adhesives are available, development of ideal hemostatic compositions that offer a range of remarkable properties including capability to effectively and immediately manage bleeding, excellent mechanical properties, biocompatibility, biodegradability, antibacterial effect, and strong tissue adhesion properties, under wet and dynamic conditions, still remains a challenge. Benefiting from tunable mechanical properties, high porosity, biocompatibility, injectability and ease of handling, polymeric hydrogels with outstanding hemostatic properties have been receiving increasing attention over the past several years. In this review, after shedding light on hemostasis and wound healing processes, the most recent progresses in hydrogel systems engineered from natural and synthetic polymers for hemostatic applications are discussed based on a comprehensive literature review. Most studies described used in vivo models with accessible and compressible wounds to assess the hemostatic performance of hydrogels. The challenges that need to be tackled to accelerate the translation of these novel hemostatic hydrogel systems to clinical practice are emphasized and future directions for research in the field are presented.

A Review of Pharmacological Treatments for Vaginal Atrophy in Postmenopausal Women in Iran

Vaginal atrophy is one of the most common menopausal complications and is often overlooked. There are various pharmacological and non-pharmacological treatment approaches to reduce vaginal atrophy; however, no comprehensive study on a convenient, affordable, inexpensive, and noninvasive treatment with fewer complications has been conducted so far. Thus, the current study aimed to provide a systematic review of pharmacological treatment for vaginal atrophy in postmenopausal women in Iran. In this systematic review, all Iranian articles published in Persian or English during 2009 to 2019 were collected and analyzed by searching the Scopus, PubMed, Web of Science, Magiran, Iranian Registry of Clinical Trials (IRCT), and Cochrane Library databases. The inclusion criteria were clinical trials for vaginal atrophy and menopause. Based on the selection criteria, articles with a Jadad scale score of 3 and above were included in the study and qualitatively analyzed. Overall, 15 clinical trials met the inclusion criteria. In total, 12 articles examined the efficacy of pharmacological treatments (including three herbal medicines, three vitamins and dietary supplements, and two chemical drugs) in treating vaginal atrophy in postmenopausal women. Various types of medication have been used to improve vaginal atrophy, and effective treatments include licorice, chamomile, royal jelly, vitamin E, vitamin D, hyaluronic acid, and Vagifem; however, the results of studies on fennel have been inconsistent. However, considering the small number of studies reviewed, further studies with a stronger methodology are needed to confirm the efficacy of these medications.

Short-term outcome of botulinum neurotoxin A injection with or without sodium hyaluronate in the treatment of infantile esotropia-a prospective interventional study

Purpose

To compare the short-term outcome of botulinum neurotoxin A (BoNT-A) with or without sodium hyaluronate in the treatment of infantile esotropia (IE).

Methods

In this tertiary care hospital-based prospective, interventional, non-randomized study on infants with IE below one year of age, 25 cases were enrolled in the sodium hyaluronate (SH) group to receive 2.5 U BoNT-A injection combined with SH in each medial rectus muscle (MR). Thirty patients were enrolled in the control group to receive 2.5 U BoNT-A injection with normal saline in each MR. The change in mean primary ocular deviation (POD) and complications were assessed at 2 weeks, 1 month, 3 months, and 6 months post injection. Mann-Whitney U test was used for non-parametric unpaired data. Chi-square test and Fisher's exact test were used to test for the strength of the association between the two categorical variables.

Results

Satisfactory ocular alignment was achieved in 76% in SH group and 73% in the control group (P value = 0.80). While the change in mean POD was comparable (29.2 prism diopters [PD] vs 29.3 PD; P value = 0.65), the complication rates were significantly lesser in SH (16% vs 33.3%; P value = 0.14).

Conclusion

BoNT-A combined with SH is equally effective with lesser complications as compared to botulinum toxin alone in the treatment of IE.

Intermediate layer contribution in placental membrane allografts

Placental membrane (PM) allografts are commonly used to treat chronic wounds. Native PM is composed of an amnion, chorion, and intermediate layer (IL) that contain matrix structures and regulatory components beneficial in wound healing. Historically, commercially available allografts were composed of only one or two layers of the PM. To maximize the conserved material in PM allografts, a dehydrated complete human placental membrane (dCHPM) allograft processed using the Clearify™ process was developed. Histological and proteomic characterization comparing dCHPM allografts with native PM demonstrated that the majority of matrix structures and regulatory proteins are retained in dCHPM allografts through processing. To evaluate the importance of maintaining the entire intact PM and the contribution of the IL, the structural and proteomic makeup of the IL was compared with that of dCHPM allografts. This is the first known characterization of regulatory proteins in the IL. Results demonstrate that the IL contains over 900 regulatory and signaling components, including chemokines, growth factors, interleukins, and protease inhibitors. These components are key regulators of angiogenesis, neurogenesis, osteogenesis, inflammation, tissue remodeling, and host defense. The results show that the proteomic composition of the IL is consistent with that of the entire dCHPM allograft. Although further investigation is required to fully understand the contribution of the IL in PM allografts, these results demonstrate that the IL contains structural and regulatory proteins that can enhance the barrier and wound healing properties of PM allografts.

Preparation and biological evaluation of a novel agarose-grafting-hyaluronan scaffold for accelerated wound regeneration

At present, seeking an effective dressing for wound regeneration has drawn considerable interest. In this paper, a novel agarose-grafting-hyaluronan (Ag-g-HA) scaffold was synthesized for rapid wound healing. Elemental analysis results showed that the HA grafting rate of Ag-g-HA was ∼69%. Ag-g-HA remained bioactive to accelerate cell proliferation and stimulate secretion of TNF-α for macrophagocyte RAW 264.7, and collagen I and collagen III for fibroblast 3T3. An i n vivo study demonstrated that Ag-g-HA showed a faster repair cycle and a better skin histological structure for a full-thickness skin defect. The collagen I, collagen III and TNF-α secreted by mice for Ag-g-HA were similiar to HA. Ag-g-HA showed a similiar biological activity to HA but had a longer degradation time through its improved insolubility. These findings demonstrate that the Ag-g-HA scaffold accelerated wound healing, and could be a promising novel scaffold for tissue engineering and regenerative medicine.

Five-year results of viscotrabeculotomy versus conventional trabeculotomy in primary congenital glaucoma: A randomized controlled study

PURPOSE

To assess the long-term results of viscotrabeculotomy in infants with primary congenital glaucoma and to compare its outcome with conventional trabeculotomy.

PATIENTS AND METHODS

A prospective randomized comparative study included infants with primary congenital glaucoma younger than 2 years. Patients were divided into two groups: viscotrabeculotomy group and conventional trabeculotomy group. Preoperative and postoperative intraocular pressures, corneal diameter, intraoperative and postoperative complications, and success rates were compared between two groups. All the patients were followed up for 5 years.

RESULTS

The study included 154 eyes of 92 infants distributed randomly among the two groups; 78 and 76 eyes in viscotrabeculotomy and conventional trabeculotomy groups, respectively. In both groups, there was a statistically significant intraocular pressure reduction at all time points of the follow-up periods compared to the preoperative values (p < 0.0001). At 5 years, viscotrabeculotomy group showed significant reduction of the mean postoperative intraocular pressure (49.47%) than conventional trabeculotomy group (48.64%) (p < 0.0001). Intraocular pressure was statistically lower in viscotrabeculotomy starting from 12th month and till the end of the follow-up. At 5 years, the total success rate of viscotrabeculotomy group was 89.74% compared to 85.53% in conventional trabeculotomy group without significant difference (p = 0.487). The postoperative mean values of the cup/disk ratio in viscotrabeculotomy group showed statistically lower values compared to conventional trabeculotomy group (p = 0.019). Postoperative hyphema was statistically higher in conventional trabeculotomy group (p < 0.0001). All eyes that underwent a reoperation before 5 years follow-up were excluded from the statistical workup of the study after reoperation, except for calculation of success/failure.

CONCLUSION

Viscotrabeculotomy and conventional trabeculotomy proved to be effective in cases of primary congenital glaucoma. Viscotrabeculotomy appeared to have prolonged stability in controlling the intraocular pressure with higher success rates and lower complications.