Hyaluronic Matrix Research Articles

Near-infrared light activated rapidly separable polymeric microneedles for transdermal biologics delivery

Polymeric microneedles (PMNs) are an attractive transdermal drug delivery approach with minimal invasiveness and improved patient compliance. However, it is uncomfortable and inconvenient for patients to wear a PMN patch for hours or days until complete payload release. Here, we report a facile strategy to fabricate rapidly separable PMN arrays activated by near-infrared (NIR) light (NIR-RS-PMN) with enhanced mechanical strength through introduction of a photothermal-sensitive spacer integrating plasmonic gold nanorods into a biocompatible sodium hyaluronate matrix. Under NIR irradiation, the NIR-RS-PMN achieved rapid separation of the patch backing and microneedles within 1 min. The loaded bioactive therapeutics, e.g., insulin and RNA, were well-preserved during fabrication, NIR irradiation, and 20-day storage at room temperature. The NIR-RS-PMN was well tolerated by rats without skin irritation. Its feasibility for biologics delivery was further established by the treatment of diabetic rats with insulin encapsulated PMNs. The innovative PMNs increase ease of use and achieve effective and precise payload delivery, which may increase access to biopharmaceuticals and vaccines in remote and resource-limited communities.

Synthesis and Investigation of Physicochemical and Biological Properties of Films Containing Encapsulated Propolis in Hyaluronic Matrix

The dynamic development of nanotechnology has enabled the development of innovative and novel techniques for the production and use of nanomaterials. One of them is the use of nanocapsules based on biodegradable biopolymer composites. Closing compounds with antimicrobial activity inside the nanocapsule cause the gradual release of biologically active substances into the environment, and the effect on pathogens is regular, prolonged and targeted. Known and used in medicine for years, propolis, thanks to the synergistic effect of active ingredients, has antimicrobial, anti-inflammatory and antiseptic properties. Biodegradable and flexible biofilms were obtained, the morphology of the composite was determined using scanning electron microscopy (SEM) and particle size was measured by the dynamic light scattering (DLS) method. Antimicrobial properties of biofoils were examined on commensal skin bacteria and pathogenic Candida isolates based on the growth inhibition zones. The research confirmed the presence of spherical nanocapsules with sizes in the nano/micrometric scale. The properties of the composites were characterized by infrared (IR) and ultraviolet (UV) spectroscopy. It has been proven that hyaluronic acid is a suitable matrix for the preparation of nanocapsules, as no significant interactions between hyaluronan and the tested compounds have been demonstrated. Color analysis and thermal properties, as well as the thickness and mechanical properties of the obtained films, were determined. Antimicrobial properties of the obtained nanocomposites were strong in relation to all analyzed bacterial and yeast strains isolated from various regions of the human body. These results suggest high potential applicability of the tested biofilms as effective materials for dressings to be applied on infected wounds.

Microcomputed tomographic analysis of bone microarchitecture after sinus augmentation with hyaluronic matrix: a case-control study.

The aim of this study was to analyze trabecular microarchitecture of augmented sinuses with hyaluronic matrix and xenograft by microcomputed tomography, and to investigate whether hyaluronic matrix has an effect on the newly formed bone quality. Thirteen patients undergoing maxillary sinus augmentation were included in this split-mouth study. Right and left sinus sites were randomly assigned to test and control group. In test group, the sinus was grafted with hyaluronic matrix and xenograft; in control group, only with xenograft. Four months after augmentation, bone samples were harvested during implant placement and analyzed for the following trabecular microarchitecture parameters using microcomputed tomography: bone volume (BV), total volume (TV), bone volume fraction (BV/TV), bone surface (BS), specific bone surface (BS/BV), bone surface density (BS/TV), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), trabecular pattern factor (Tb.Pf), and fractal dimension (FD). There was statistically significant difference only for BS/TV parameter between two groups. BS/TV was higher in hyaluronic matrix group compared with control group. Addition of hyaluronic matrix to xenograft may enhance bone quality in terms of bone surface density. However, more research investigating the microstructural variation of augmented sinuses is needed with a greater sample.

Aloe vera-based antibacterial porous sponges for wound dressing applications

The antibacterial sponges with high macroporosity, high interconnectivity and high biocompatibility is a significant concern for wound healing applications. In this work, novel Aloe vera (AV) based sponges were developed via subsequent lyophilization with further chemical crosslinking throughout the double network sponges. Single network was composed of gelatin-sodium alginate (G-SA) while the double network using gelatin-sodium alginate- sodium hyaluronate (G-SA-HA) was produced with the addition of hyaluronic acid solution into the gelatin-sodium alginate matrix. Lastly, Aloe vera as the bioactive agent was fabricated throughout the gelatin-sodium alginate-sodium hyaluronate matrix. The AV-based sponges demonstrated large pores with high interconnectivity. The swelling degree of the AV-based sponges were higher than that of G-SA and G-SA-HA sponges. The release of AV from the sponges reached an equilibrium value after 24 h showing a more controlled release at pH 5.5 than at pH 7.4. AV-based sponges showed antibacterial activity against Staphylococcus aureus, Enterococcus faecalis, Streptococcus pneumoniae and Bacillus cereus and displayed any cytotoxicity against Mesenchymal stem cells.

Supramalleolar osteotomy and AMIC cartilage reconstruction in severe cartilage lesion

Category: Ankle Introduction/Purpose: Severve cartilage lesion is defined by the author as: Cartilage substantial deterioration of the subchondral bone Kissing lesion, tibial and talar lesion. Gross cystic lesion Cartilage damage greater than 1/3 of the talar dome or the tibial platform Slerotic changes of the subchondral bone plate in arthritic cases in severe hindfoot varus or valgus alignment. This paper shows in a case series, exceptional cartilage lesions with the above mentioned pathological changes. The indications, strategies for osteotomies and the treatment strategies in malaligned bipolar, cystic and gross cartilage lesions is explained. Methods: 35 patients with severe circumscript varus / valgus arthritis have been operated by supramalleolar osteotomy (SMOT), 11 of them with (tibial & talar “kissing”) lesions. 70 patients presented bipolar (tibial & talar “kissing”) lesions with correct hindfoot axis. 18 patients had a gross cystic lesion and were additionally treated with filling of the cysts. 2 of them had a “kissing lesion”. Results: All patients received an AMIC procedure (hyaluronic matrix, Hyalofast©) for cartilage reconstruction. The biological healing support was in all cases bone marrow aspirate and ACP© growth factors. The subchondral bone plate was treated aggressively was a power raps or burr according to L. Johnson technique The importance of a supramalleolar and calcaneous osteotomy in a hindfoot malalignment (varus / valgus) as a treatment key aspect for load transfer is elaborated. Planned early implant removal with revision und biological boosting of the cartilage regeneration is a further cornerstone of the treatment. Followup were evaluated by FAOS score Conclusion: This cases series have shown the possibilities for a successfull managing of this severe lesions and offers also its limit in the over all results.

Evaluation of hyaluronic matrix efficacy in sinus augmentation: a randomized-controlled histomorphometric and micro–computed tomography analysis

The objective of the present study was to test the hypothesis that the addition of hyaluronic acid–based matrix to collagenated heterologous bone graft for sinus augmentation would enhance bone formation compared to collagenated heterologous bone graft alone in the early healing period, by micro−computed tomography and histomorphometry. Thirteen systemically healthy patients requiring bilateral two-stage maxillary sinus augmentation (residual crest height≤4mm) were enrolled in this split-mouth prospective randomized controlled study. One sinus side as a control group was grafted with only collagenated heterologous bone graft; the other region as a test group was grafted with hyaluronic matrix and collagenated heterologous bone graft. Bone biopsy samples were taken after 4 months during the dental implant surgery and analyzed using micro−computed tomography and histomorphometric parameters. According to the micro−computed tomography and histomorphometric results, a significantly higher percentage of new bone was observed in the test group when compared to the control group after 4 months of healing.This study confirmed the hypothesis that the addition of hyaluronic matrix to collagenated heterologous bone graft for sinus augmentation enhances bone formation compared to collagenated heterologous bone graft alone in the early healing period.

Adrenomedullin in the growth modulation and differentiation of acute myeloid leukemia cells

Adrenomedullin (ADM) is a regulatory peptide endowed with multiple biological effects, including the regulation of blood pressure, cell growth and innate host defence. In the present study, we demonstrated that ADM signaling could be involved in the impaired cellular differentiation of myeloid leukemia cells to mature granulocytes or monocytes by modulating RAMPs/CRLR expression, PI3K/Akt cascade and the ERK/MAPK signaling pathway. When exogenously administered to in vitro cultures of HL60 promyelocytic leukemia cells, ADM was shown to exert a strong proliferative effect with minimal upregulation in the expression level of monocyte antigen CD14. Notably, the experimental inhibition of ADM signaling with inhibitor ADM22-52 promoted a differentiative stimulation towards monocytic and granulocytic lineages. Moreover, based on the expression of CD31 relative to CD38, we hypothesized that an excess of ADM in bone marrow (BM) niche could increase the transendothelial migration of leukemia cells while any inhibitory event of ADM activity could raise cell retention in hyaluronate matrix by upregulating CD38. Taken into consideration the above evidence, we concluded that ADM and ADM22-52 could differently affect the growth of leukemia cells by autocrine/paracrine mechanisms and may have clinical relevance as biological targets for the intervention of tumor progression.

Are conduits superconductor-like and supported by tetrahedra structure of hyaluronic matrix in living systems? New perspectives

All biological-medical treatments need a ground regulation in the intermeshed control loop system in animate matter. The focus of our contribution is to suggest a possible mechanism in this interconnected system that will work in order to supply/assist a higher ordered servo loop. Bonghan ducts indicate similarities to so-called meridians or conduits that are the central part in Chinese Medicine for the energy Qi. It is assumed that the nervous system demands a highly redundant and rapid communication system (RCS) probably established via the extracellular matrix (ECM) and triggered by a threshold value for the entire body. Metabolic processes could work in the picosecond's range while the nervous system is on the time scale at least one order of magnitude lower; probably most of them in the millisecond range. Long-range coherent electromagnetic phenomena and recent experiments indicate a structured superconducting-like system with the Josephson-effect behavior in biological systems. In the ECM are the components proteoglycans and glycosaminoglycans (PG/GAGs) and among them the ubiquitarian hyaluronic acid plays probably an important role and can behave as liquid crystals while the charge transport is performed via proton "jumping" in the proton-chains. Therefore, the water molecules have to be confident on a nanometer scale, lowering their energy states, and set up a phase transition with a rapid jumping of the protons through the water-carbon-chains. These partial chains could probably be modeled by tiny pyramids of the atoms. We propose that in order to set up those long-range coherent effects, a vortex is created. By doing Qi Gong, an energetic vortex through the body is established and the entire body can be modeled by two-base plane-faced pyramids acting as a tunable cavity resonator obeying electrodynamics laws. Therefore, the phenomenon's of pyramids should be considered in animate and inanimate matter in order to achieve long-range coherent effects, which by now controversially discussed and to go new ways to come over the clutter.

In vitro drug release from HYC 141, a corticosteroid ester of high molecular weight hyaluronan

The use of steroid drugs bound covalently to hyaluronate through ester linkages has been proposed for local treatment of arthritic diseases. The in vitro release profile of HYC 141, formed by linking covalently methylprednisolone to a soluble high molecular weight hyaluronate matrix, was studied. First, the influence of various parameters (temperature, pH, protein content, viscosity), in the range of the physiopathological values, was investigated in buffer medium. The release of methylprednisolone was five-fold slower at 20°C than at 37°C and diminished further when the HYC 141 concentration was increased. The HYC 141 was more stable below neutral pH than above it, and this was not dependent on the protein content of the medium. Secondly, the release of methylprednisolone was studied in plasma and synovial fluid from patients with inflammatory arthritides. The T50% was similar in both samples and ranged from 3.2 to 5.9 h, but was faster than in phosphate buffer of corresponding pH (22–39 h). These results suggest that the release profile of HYC 141 depends on the physico-chemical parameters of the medium and possibly on the chemical conformation of hyaluronate. In human samples, hydrolysis seems to be controlled by an esterase activity. This hypothesis was strengthened by using an acylating inhibitor that reduces the hydrolysis rate of ester linkages.

Enhanced diffusivity of glucose in a matrix of hyaluronic acid.

The diffusion coefficients for glucose and sucrose within matrices of hyaluronic acid are contrasted with coefficients determined in matrices of agarose. Diffusivity is similar in 0.5 and 1% matrices of both polysaccharide polymers dissolved in saline (0.9% NaCl solution) buffered at pH 7.4 with 0.01 M sodium phosphate. In a 2.5% matrix of hyaluronate, but not agarose, glucose diffusivity is enhanced 3-fold, whereas simultaneously determined sucrose diffusivity remains unchanged from that in the 1% matrix. The 1% hyaluronate matrix will enhance glucose diffusivity if an inorganic cationic serum constituent(s) with a molecular weight of less than 500 is incorporated into the solvent. This enhanced diffusivity is inversely dependent on glucose concentration and on the degree of polymerization of the hyaluronate in the matrix. The presence of an appropriately constituted matrix of hyaluronic acid endows the resultant fluid with several properties generally ascribed to membranes: permselectivity (even glucose and sucrose behave differently), saturability, and the potential to enhance translational movement of selected solutes such as glucose.

Regeneration in Sabellid Annelids

Sabellid regeneration and the expression of polarity are known to be under direct neural control. During regeneration nerves exhibit both neurotrophic and neurosecretory capacities. Indeed, it is proposed that the basic neurotrophic control mechanism is neurosecretory in nature, involving the synthesis, packaging and transport of neurosecretory granules to the wound site. The expression of polarity is envisioned as a cellular differentiating response to a threshold increase in neurohormone. Under maximal stimulus, anterior regeneration involves the sequential synthesis and assembly of a rich hyaluronate matrix followed by the deposition of chondroitin sulfate and collagen to form the normal adult crown. Posterior regeneration, according to the model, is under minimal stimulation and does not progress beyond the hyaluronate stage. The relationship between neural control and the assembly of extracellular macromolecules during regeneration is discussed in relation to the proposed model.