Semih Akkaya’s research while affiliated with Istanbul Surgery Hospital and other places

Strain ratio measurements of tendons vary because of the reference tissue selection. The main purpose of this study is to highlight, in detail, the numeric variability attributable to the use of various reference materials on strain ratio measurements of patellar and Achilles tendons. Measurements were performed at the proximal, middle and distal thirds of the patellar and Achilles tendons on the dominant site of healthy volunteers. A total of 3 references were used: the Hoffa's fat pad for the patellar tendon, the Kager's fat pad for the Achilles tendon, subcutaneous tissue and Aquaflex gel pads (Parker Laboratories, Fairfield, NJ, USA)for both tendons. Although the same methods were used by the same physician for each tendon site on repeated measurements, strain ratio values had numeric variability with various reference materials in each measurement. Therefore, comparison of numeric strain ratio results of various studies with various reference materials could confuse the clinical interpretations of these numeric data, and, using a reference material with standard stiffness like Aquaflex ultrasound gel pads, should be considered by verifying these results with further studies.

Objective The aim of the study was to investigate the relation between health‐related quality of life and risk of falling, fear of falling, and functional status in patients with hip arthroplasty. Methods In this cross‐sectional study, 48 hips of 45 patients who aged between 33 and 79 (53.56 ± 12.50) years and had cementless total hip arthroplasty between 2010 and 2014 were evaluated. Twenty‐seven of the patients participated in the study were female (60.0%) and 18 were male (40.0%). Health‐related quality of life with Nottingham Health Profile, function of the hip joint with Harris Hip Score, risk of falling with Performance‐Oriented Motion Assessment I, and fear of falling with Falls Efficacy Scale were assessed. In addition, chair stand test, 40‐m walk test, stair‐climb test, and single leg stance test were carried out. In analysing the relationships between these parameters, Pearson correlation analysis was employed. The level of significance was considered as p < 0.05. Results Among the cases, who were evaluated 87.10 ± 45.22 (22.43–214.71) weeks after the operation, a significant correlation was found between health‐related quality of life and risk of falling, function of hip joint, and functional tests (p < 0.05). Conclusion The evaluation of the factors related to health‐related quality of life in hip arthroplasty patients may help identify patient needs and guide the rehabilitation process.

Pregabalin sitotoksisitesi

GİRİŞ VE AMAÇ: Bu bilimsel araştırma projesinde; dejenere veya intakt dokulardan elde edilen hücre kültürlerinde yer alan nukleus pulposus (NP)'a spesifik belirteçlere ait gen ekspresyon paternlerinin belirlenebilmesi amaçlandı. YÖNTEM: Dahil edilme kriterlerini karşılayan ve dokuları kullanılan olguların yaş aralığı, 26 ile 56 yıl aralığında idi. Primer hücre kültürleri hazırlamak için dokular; lomber disk hernisi tanısı ile lomber mikrodiskektomi yapılan (n=12) ve spinal travma sonrası travmatik intervertevbral diskektomi, korpektomi ile beraber diskektomi yapılan (n=12) toplam 24 olgudan elde edildi. Sıfırıncı saat, 24. ve 48. saatlerde, bu düzeneklerde yer alan örnekler içerisinde, NP spesifik belirteçleri ve ekstraselüler matriks yapısına ait belirtecin gen ifadeleri, kantitatif eş zamanlı polimeraz zincir reaksiyonu (qRT-PCR) ile test edildi. Aynı zaman dilimlerinde tüm örneklerde, invert ışık ve floresan mikroskobileri ile görsel değerlendirmeler de gerçekleştirildi. Hücre sınıflarına ait canlılık ve proliferasyon analizleri ise spektrofotometrik olarak değerlendirildi. Elde edilen verilerin istatistiksel değerlendirilmesinde, kategorik değişkenler için Spearman, sayısal ve normal dağılım gösteren değişkenler için Pearson korelasyon testleri kullanıldı. BULGULAR: Doku cinsi ile kültürizasyonun süresi arasında (r=0.000; p=1.000) ve dokunun elde edildiği bölge ile HIF-1α gen ekspresyonları arasında (r=0.098; p=0.245) bir ilişki saptanamadı. Hücre proliferasyonu ve CHAD ekspresyonu arasında korelasyon bulunamaz iken, COL2A1 ile CHAD gen ekspresyonları arasında anlamlılık ölçüsünde korelasyon olmadığı görüldü. CHAD ile HIF-1α gen ifadeleri ile HIF-1α ile COL2A1 gen ekspresyonlarının hücre proliferasyonunu etkilediği anlaşıldı. TARTIŞMA VE SONUÇ: Deneysel araştırmalarda kullanılacak olan hücre kültür düzenekleri ve bu düzeneklerde kullanılacak olan hücrelerin eksprese ettikleri gen ifadesi değişim düzeyleri oldukça önemlidir. Anahtar Kelimeler: Dejeneratif disk hastalıkları, farmakomoleküler terapi, primer-hücre-kültürü.

The aim of the present study was to investigate the effects of three different formulations of hyaluronic acid (HA): Low molecular weight (MW) Sinovial One®, medium MW Viscoplus® and high MW Durolane®, on chondrocyte proliferation and collagen type II (COL2A1), hypoxia‑inducible factor 1α (HIF‑1α) and chondroadherin (CHAD) expression in primary chondrocyte cultures. Standard primary chondrocyte cultures were established from osteochondral tissues surgically obtained from 6 patients with gonarthrosis. Cell morphology was evaluated using an inverted light microscope; cell proliferation was determined with a MTT assay and confirmed with acridine orange/propidium iodide staining. Levels of CHAD, COL2A1 and HIF‑1α expression were assessed using specific TaqMan gene expression assays. The results demonstrated the positive effect of HA treatment on cell proliferation, which was independent from the MW. COL2A1 expression increased in the medium and high MW HA treated groups. It was observed that HIF‑1α expression increased in the high MW treated group alone. CHAD expression increased only in the medium MW HA treated group. Evaluation of gene expression revealed that levels of expression increased as the duration of HA application increased, in the medium and high MW HA treated groups. In terms of increased viability and proliferation, a longer duration of HA application was more effective. Taken together, it may be concluded that the administration of medium and high MW HA may be a successful way of treating diseases affecting chondrocytes in a clinical setting.

Purpose: The aim of the present study is to investigate the effects of three different hyaluronic acid (HA) formulations [Low-Molecular Weight (MW) 50 mg/2.5 mL (Sinovial One®), Medium-MW 75 mg/3 mL (Viscoplus®), High-MW 60 mg/mL (Durolane®)] on chondrocyte proliferation and collagen type II (COL2A1), Hypoxia-inducible factor 1-alpha (HIF1α) and Chondroadherin (CHAD) gene expression of chondrocytes. Methods: Standard primary chondrocyte cultures were performed using the osteochondral tissues surgically obtained from 6 patients with gonarthrosis. Cell morphology was evaluated using an inverted microscope; cell proliferation was determined with the MTT analysis, confirmed by AO/PI staining and evaluated statistically. The expression levels of CHAD, COL2A1 and HIF1α genes were assessed using gene specific TaqMan Gene Expression Assays. Results: Our results showed the positive effect of HA treatment on cell proliferation independent from molecular weight of HA. COL2A1 gene expression increased in medium and high-MW HA treated groups. It was observed that only at high-MW HA-administered samples HIF1α expression was higher than other experimental groups. CHAD expression was increased only in the experimental group that medium-MW HA applied. Conclusions: When the gene expression results are evaluated, it was observed that the gene expression levels increases as the duration of HA application increases in medium and high-MW HA treated experimental groups. In terms of viability and proliferation, duration of HA application was found to be effective. When all the data are evaluated together, we can conclude that administration of medium and high-MW HA could provide a more successful treatment in the clinical practice.

The integration of stem cell technology and cell sheet engineering improved the potential use of cell sheet products in regenerative medicine. This review will discuss the use of mesenchymal stem cells (MSCs) in cell sheet-based tissue engineering. Besides their adhesiveness to plastic surfaces and their extensive differentiation potential in vitro, MSCs are easily accessible, expandable in vitro with acceptable genomic stability, and few ethical issues. With all these advantages, they are extremely well suited for cell sheet-based tissue engineering. This review will focus on the use of MSC sheets in osteogenic tissue engineering. Potential application techniques with or without scaffolds and/or grafts will be discussed. Finally, the importance of osteogenic induction of these MSC sheets in orthopaedic applications will be demonstrated.

It is primarily aimed to study polymorphisms in vitamin D receptor gene (VDR), which is one of the genetic factors having a role in the formation of lumbar pathologies and/or causing higher incidence of pathologic processes. Secondarily, it is aimed to create pre-data which may help professionals to administer more effective and protective interventions in this area. Without any language preference, we searched US National Library of Medicine National Institutes of Health, Embase, OVID, Cochrane Library database of clinical trials from 1989 to Mar 11 to 2017 Mar 12, and traced all the references of incorporated documents. The data were evaluated by using descriptive statistics. Results were shown as amount or frequency (%). In literature, some vitamin D receptor gene (VDR) polymorphisms have been found in relation to widespread osteochondral diseases. When VDR polymorphisms, vitamin D level and intervertebral disc pathologies have been examined, a satisfactory answer to the question whether specific pathologies could be suppressed in terms of genetics has not been found. By means of this study, it would be understood the genetic factors inhibiting physio pathological process concerning lumbar degenerative disc disease or the genetic factors playing role in identifying physio pathological process related to lumbar degenerative disc disease by defining them. Accordingly, effective and contraceptive treatment of lumbar degenerative disc disease might be ensured soon.

Lumbar patolojilerin oluşumunu engelleyen ve/veya daha yüksek oranlarda patolojik sürecin oluşmasına neden olan genetik faktörlerden, D vitamini reseptör geninde polimorfizmlerin tanımlanarak anlaşılması.

Purpose: Methylphenidate derivative drugs are used because of psychostimulants effects on attention deficit hyperactivity disorder in children and adults. As far as we know, toxic or antiproliferative effects of methylphenidate against cartilage tissue were not studied in the literature. The present study was carried out to investigate the possible effects of methylphenidate on the proliferation, viability, and differentiation of primary human chondrocytes, in vitro. Methods: Monolayer primary chondrocyte cultures were prepared using osteochondral tissue obtained from patients who underwent a total knee prosthesis operation. Stock solution of methylphenidate was prepared and aliquots having 1 to 1000 µM concentrations of the drug was composed. These solutions were applied to the wells containing cultured chondrocyte samples within the well-plates. Control groups were composed of pure chondrocyte culture and no solution was added into them. All groups were evaluated at 24h, 48h, and 72h in order to determine the possible negative effects of the drug on the chondrocytes. The data were evaluated by Tukey honestly significantly different test following Variance of Analysis. Results: In the group where methylphenidate was applied, it was found that viability, proliferation and stage specific embryonic antigen-1 (SSEA- 1) protein expression were decreased in comparison to the control group. Conclusions: It was emphasized that clinicians should not disregard the fact that this drug might suppress chondrocyte cell proliferation and chondrogenic differentiation.