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One of the most substantial complications in orthopedic surgeries is implant associated infection. While the implant interface can be a permissive surface for bacterial colonization, an appropriate coating on the implant can effectively hinder biofilm formation. To this aim, henna and thyme extract loaded into a chitosan (CS)/polyethylene oxide (PEO) based nanofibrous hydrogel. CS/PEO/henna and CS/PEO/thymus extract nanofibers were fabricated via two-nozzle electrospinning. The proper weight ratio of CS/PEO/herbal extract was optimized. The appropriate ratio of CS/PEO and the most suitable extract concentrations was obtained to be 7/3 (v/v) and 1 % (v/v), respectively. Contact angle measurements showed an appropriate degree of hydrophilicity in all groups including herbal loaded electrospun nanosheets. Tensile strength measurements showed that inclusion of henna and thymus made minor changes in tensile strength and strain of herbal loaded nanofiber, compared to control CS/PEO fibers. Then antibacterial tests were performed and the fibers either by themselves or when used as coating on orthopedic screws exhibited a good inhibition zone against both gram negative and gram positive bacteria. The coatings showed no adverse effect on the red blood cells in leading to hemolysis. Cytocompatibility assay indicated that the prepared nanofibrous hydrogel coating was absolutely biocompatible as tested with fibroblast cells. The results of this study indicated that our henna and thyme extracts loaded CS/PEO coatings can be used in various medical fields such as wound dressing and implantation coating to prevent bacterial adhesion, growth and generally, infection.

For the higher patient compliance in periodontal disease, the drug delivery system should be released with a mucoadhesive membrane in a higher rate to minimize the sink condition in mouth. The herbal compounds have been well known as a branch of therapeutic agents, especially for inflammatory injuries. Herein, carbopol or carbomer was employed to prepare a matrix system containing a therapeutic agent, namely Ziziphus jujuba extract. The corresponding polymer was electrospun with polyacrylonitrile, and the release process was studied in the following. Approximately, 80% of the extract was released after 60 min following the Higuchi model and the anti-inflammation reaction of the extract was confirmed after stimulating inflammation of human umbilical vein endothelial cells by lipopolysaccharide. Also, the mechanical mucoadhesion of prepared scaffold was exposed that approximately 4 N/m2 was required to separate from mucoadhesive substrates. Also, Fourier transform infrared spectroscopy confirmed the presence of cyclic saccharides belonged to Z. jujuba extract. All results have approved that the membrane prepared with carbopol and Z. jujuba extract could be used as a patch for the treatment of periodontal injuries.

The inductive effects of increased osmolarity on chondrogenesis are well approved. However, the effects of the osmolyte agent invoked to induce hyperosmolarity are largely neglected. Herein, we scrutinized how hyperosmotic conditions acquired by addition of different osmolytes would impact chondrogenesis. We briefly assessed whether such conditions would differentially affect hypertrophy and angiogenesis during MSC chondrogenesis. Chondrogenic and hypertrophic marker expression along with VEGF secretion during adipose-derived (AD)-MSC chondrogenesis under three osmolarity levels (350, 450, and 550 mOsm) using three different osmolytes (NaCl, sorbitol, and PEG) were assessed. MTT assay, qRT-PCR, immunocytochemistry, Alcian Blue staining, ELISA, and ALP assays proved osmolyte-type dependent effects of hyperosmolarity on chondrogenesis, hypertrophy, and angiogenesis. At same osmolarity level, PEG had least cytotoxic/cytostatic effect and most prohibitive effects on angiogenesis. As expected, all hyperosmolar conditions led to enhanced chondrogenesis with slightly varying degrees. PEG and sorbitol had higher chondro-promotive and hypertrophy-suppressive effects compared to NaCl, while NaCl had exacerbated hypertrophy. We observed that TonEBP was involved in osmoadaptation of all treatments in varying degrees. Of importance, we highlighted differential effects of hyperosmolarity obtained by different osmolytes on the efficacy of chondrogenesis and more remarkably on the induction/suppression of cartilage pathologic markers. Our study underlies the need for a more vigilant exploitation of physicobiochemical inducers in order to maximize chondrogenesis while restraining unwanted hypertrophy and angiogenesis.

The efficacy of existing articular cartilage defect repair strategies are limited. Native cartilage tissue forms via a series of exquisitely orchestrated morphogenic events spanning through gestation into early childhood. However, defect repair must be achieved in a non-ideal microenvironment over an accelerated time-frame compatible with the normal life of an adult patient. Scaffolds formed from decellularized tissues are commonly utilized to enable the rapid and accurate repair of tissues such as skin, bladder and heart valves. The intact extracellular matrix remaining following the decellularization of these relatively low-matrix-density tissues is able to rapidly and accurately guide host cell repopulation. By contrast, the extraordinary density of cartilage matrix limits both the initial decellularization of donor material as well as its subsequent repopulation. Repopulation of donor cartilage matrix is generally limited to the periphery, with repopulation of lacunae deeper within the matrix mass being highly inefficient. Herein, we review the relevant literature and discuss the trend toward the use of decellularized donor cartilage matrix of microscopic dimensions. We show that 2-µm microparticles of donor matrix are rapidly integrate with articular chondrocytes, forming a robust cartilage-like composites with enhanced chondrogenic gene expression. Strategies for the clinical application of donor matrix microparticles in cartilage defect repair are discussed.

A method for the determination of nickel(II) by stripping voltammetry is described. The method is based on the adsorptive accumulation of nickel(II) calconcarboxylic acid complex onto a hanging mercury drop electrode (HMDE), followed by the reduction of the adsorbed complex using differential pulse voltammetry. The optimum operating conditions and parameters were found to be 0.05 M NH3/NH4Cl buffer (pH = 9.5) as the supporting electrolyte, a ligand concentration of 1 × 10−6 M, accumulation potential of −0.5 V (vs. Ag/AgCl) and accumulation time of 60 s. At the optimized conditions, the peak current is proportional to the concentration of nickel in the range of 1.7 × 10−9 to 4.7 × 10−7 M (0.1–28 ng ml−1) with a detection limit of 0.05 ng ml−1. The relative standard deviation (n = 10) at nickel concentrations of 2, 10 and 15 ng ml−1 varies in the range 0.76 to 2.1%. Possible interferences by metal ions, which are of great significance in real matrices, have been studied. The method was successfully applied to the determination of nickel content in a chocolate sample.