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Introduction:The purpose of the present study seeks to determine the signal timing of BMP–7 and TGF-β1 from a novel chitosan based hydrogel system that may affect chondrocyte proliferation resulting in the presence of a synergism seen conspicuously in consecutive controlled delivery.Methods:Four groups of cultured chondrocytes were seeded on a novel designed chitosan based hydrogel. The hydrogel was left empty (control) in one group and loaded with BMP–7, TGF-β1 and their combination in the other groups, respectively. Hydrogel structure was analyzed with scanning electron microscope. The release kinetics of Growth Factors (GFs) was determined with ELISA. Chondrocyte viability and toxicity after being tested with MTS and collagen type II synthesis, were quantified with western blotting. Canonical regression analysis was used for measuring statistical evaluation.Results:Chitosan based hydrogel allowed controlled release of GFs in different time intervals for BMP–7 and TGF-β1. Double peak concentration gradient was found to be present in the group loaded with both GFs. In this group, substantially higher chondrocyte growth and collagen synthesis were also detected. Conclusions:We concluded that, chitosan based hydrogel systems may be adjusted to release GFs consecutively during biodegradation at the layers of surface, which may increase the cell number and enhance collagen type II synthesis.

High-pressure injection injuries to the hand are uncommon soft tissue traumas of the hand which are frequently underestimated. They are, however, not uncommon among workers in industry using paint, automotive grease, solvents and diesel oil. The prognostic factors are the type, amount and temperature of the material and the pressure of injection. The results of 14 surgically treated high-pressure injection injuries of the hand with a minimum of two years follow-up are reported. Ten cases required soft tissue debridement and foreign body removal. Six required reconstructive microsurgical procedures and one underwent digital tip amputation, which followed major and devastating soft tissue problems. In the present study, we describe the mechanism of the soft tissue damage and the principles of treatment. This study confirms the fact that high-pressure injection injury to the hand is a significant problem, which can easily lead to serious sequelae and, even, amputation.

The aim of this study was to investigate effects of bone impaction technique on tunnel enlargement after ACL reconstruction at a minimum 2 years follow-up. Two groups of patients who had been operated upon with the same arthroscopic technique with the exception of tibial tunnel constitution were compared. Twenty-one patients of group A (drilling to 6 mm followed enlargement to 8-9 mm by using dilators) and 23 patients of group B (directly drilling to the size of the graft) were evaluated clinically and radiographically based on multislice computerised tomography (MSCT) retrospectively. At follow-up, there was no statistical difference between tunnel diameters between two groups at the femoral site, but significant difference at the tibial site (p= 0.00192 for coronal; p=0.0171 for sagittal diameter). Both groups were comparable according pre-and postoperative Lysholm and IKDC scores (p<0.5 Mann-Whitney U test). Compacted tunnel walls may resist enlargement, suggesting this technique resulted in better tunnel diameter values especially with intratunnel fixation.

A AB BS ST TR RA AC CT T O Ob bj je ec ct ti iv ve e: : Both Bone Morphogenetic Protein 7 (BMP-7) and Transforming Growth Factor Beta 1 (TGF-β1) have stimulating effects on chondrocyte proliferation. These growth factors act at different time points of the biological repair process. We aimed to design a hydrogel, which would enable consecutive controlled release of the growth factors. M Ma at te er ri ia al l a an nd d M Me et th ho od ds s: : We designed a chitosan particle impregnated Poly (vinylalcohol) (PVA)-borax hydrogel (CPBH). CPBH allowed controlled release of BMP-7 and TGF-β1 at different time points. Hydrogel structure was analyzed by Scanning Electron Microscope (SEM). The release kinetics of Growth Factors (GFs) were determined with enzyme-linked immunosorbent assay (ELISA) and UV-spectrophotometer. Chondrocyte viability and toxicity were tested through CellTiter 96 ® Non-Radioactive Cell Proliferation (MTS) ELISA. R Re es su ul lt ts s: : The designed hydrogel showed high swelling and mucoadhesion characteristics under acidic conditions. CPBH released BMP-7 first and rapidly and TGF-β1 consecutively and slowly. It also allowed controlled release of protein/peptide based drugs for 21 days without altering their bioactive properties. At the end of 21 days, 82.62% of BMP-7 and 98.34% of TGF-β1 were consecutively released. The difference between the groups was significant (for TGF-β1, p<0.05 and for BMP-7, p<0.001). C Co on nc cl lu us si io on n: : The controlled and slow release of growth factors has been shown to be beneficial on cartilage regeneration. As it is not cytotoxic, we suggest that this hydrogel might be used in medical and pharmaceutical applications areas. K Ke ey y W Wo or rd ds s: : Delayed-action preparations; hydrogels; TGF-β1 protein, human; bone morphogenetic protein 7 Ö ÖZ ZE ET T A Am ma aç ç: : Kemik Morfojenik Proteini-7 (BMP-7) ve Transforme edici Büyüme Faktörü Beta-1 (TGF-β1)'in kıkırdak hücreleri üzerinde prolifere edici etkileri bulunmaktadır. Bu büyüme faktörlerinin etkisi biyolojik tamir sürecinin farklı zamanlarında gerçekleşmektedir. Bu çalışmada, büyüme faktörlerinin ardışık ve kontrollü olarak salınımını gerçekleştirecek bir hidrojel tasarlamayı amaçladık. G Ge er re eç ç v ve e Y Yö ön nt te em ml le er r: : Bu amaçla kitosan emdirilmiş polivinil alkol (PVA)-boraks hidrojeli (CPBH) tasarlandı. Bu hidrojel BMP-7 ve TGF-β1'in farklı zamanlarda kontrollü salınımını sağladı. Tasarladığımız hidrojelin yüzey yapısı taramalı elektron mikroskobu (SEM) ile değerlendirildi. Büyüme faktörlerinin salım kinetiği enzim aracılı immün deney (ELISA) ve ultraviyole (UV)spektrofotometre ile saptandı. Kondrosit canlılığı ve toksisite testi "CellTiter 96 ® Non-Radioactive Cell Proliferation (MTS)" ELISA yöntemiyle değerlendirildi. B Bu ul lg gu ul la ar r: : Tasarlanan hidrojel, asidik ortam koşullarında büyük oranda şişme ve mukoadezyon özellikleri sergiledi. CPBH, önce hızlı bir biçimde BMP-7'nin, sonra da yavaş olarak TGF-β1'in salınımını ardışık olarak gerçekleştirdi. İçerisindeki p...