Person:
TOK, OLGU ENİS

Loading...
Profile Picture
Status
Kurumdan Ayrılmıştır
Organizational Units
Organizational Unit
Job Title
First Name
OLGU ENİS
Last Name
TOK
Name
Email Address
Birth Date

Search Results

Now showing 1 - 10 of 17
  • PublicationOpen Access
    Comparison of Small-diameter-hole and Traditional Microfracture in Cartilage Repair and the Effect of Adding a Hyaluronic Acid-based Acellular Matrix Scaffold: An Animal Study
    (2021-03-01T00:00:00Z) UÇAN, VAHDET; YILDIZ, FATİH; ELMADAĞ, Nuh Mehmet; UZER, GÖKÇER; GÜZEL, YUNUS; TOK, OLGU ENİS; Mukaddes, E.; UÇAN, VAHDET; YILDIZ, FATİH; ELMADAĞ, NUH MEHMET; UZER, GÖKÇER; TOK, OLGU ENİS; EŞREFOĞLU, MUKADDES
    Objective: Since, there is no standardized technique for the treatment of focal cartilage defects that can recreate original cartilage tissue; researchers continue to explore and evaluate various treatment modalities. This study compared post-operatke healing of cartilage defects after treatment with small-diameter-hole microfracture (SDHM) technique with that of traditional microfracture technique. The effects of the hole density and augmentation with hyaluronic acid-based acellular matrix (HA-based AM) on cartilage healing were also investigated. Methods: Articular cartilage defects measuring 5 mm in diameter and 3 mm in depth were created in each femoral trochlear groove of 21 New Zealand rabbits. Rabbits were assigned to seven groups comprising six knees each. The rabbits were sacrificed 12 weeks later, and the regenerated cartilage was harvested for histological evaluation using the Wakitani scoring system. Results: All defects were filled with regenerated tissue macroscopically. Group I (14; range 10-14 points) had significantly higher Wakitani score than in groups VI (6; range 1-11 points) and VII (5; range 3-10 points) (p=0.043 and p=0.016, respectively). No significant differences were observed among the other groups. Augmentation with HA-based AM did not contribute to cartilage healing. Conclusion: Improved cartilage healing was observed with increasing SDHM density than with traditional microfracture technique. SDHM combined with HA-based AM implantation did not improve the quality of the regenerated cartilage.
  • PublicationMetadata only
    Mito Tracker labeling in HepG2 Cell Cultures: Influence of different staining techniques on the morphology of mitochondria.
    (2012-01-01T00:00:00Z) Aktasl, R. G.; KARAHUSEYINOGLU, S.; Karabork, M.; TOK, OLGU ENİS; Yucel, D.; TOK, OLGU ENİS
  • PublicationMetadata only
    Melatonin protects against ischemic heart failure in rats
    (2013-09-01T00:00:00Z) Sehirli, Ahmet Ozer; Koyun, Derya; TETİK, ŞERMİN; ÖZSAVCI, DERYA; YIGINER, Omer; ÇETİNEL, ŞULE; Tok, Olgu Enis; Kaya, Zehra; AKKİPRİK, MUSTAFA; Kilic, Ertugrul; Sener, Goksel; TOK, OLGU ENİS
    Ischemic injury, which occurs as a result of sympathetic hyperactivity, plays an important role in heart failure. Melatonin is thought to have antiatherogenic, antioxidant, and vasodilatory effects. In this study, we investigated whether melatonin protects against ischemic heart failure (HF). In Wistar albino rats, HF was induced by left anterior descending (LAD) coronary artery ligation and rats were treated with either vehicle or melatonin (10 mg/kg) for 4 weeks. At the end of this period, echocardiographic measurements were recorded and the rats were decapitated to obtain plasma and cardiac tissue samples. Lactate dehydrogenase, creatine kinase, aspartate aminotransferase, alanine aminotransferase, and lysosomal enzymes (beta-D-glucuronidase, beta-galactosidase, beta-D-N-acetyl-glucosaminidase, acid phosphatase, and cathepsin-D) were studied in plasma samples, while malondialdehyde and glutathione levels and Na+, K+-ATPase, caspase-3 and myeloperoxidase activities were determined in the cardiac samples. Sarco/endoplasmic reticulum calcium ATPase (SERCA) and caveolin-3 levels in cardiac tissues were evaluated using Western blot analyses. Furthermore, caveolin-3 levels were also determined by histological analyses. In the vehicle-treated HF group, cardiotoxicity resulted in decreased cardiac Na+, K+-ATPase and SERCA activities, GSH contents and caveolin-3 levels, while plasma LDH, CK, and lysosomal enzyme activities and cardiac MDA and Myeloperoxidase (MPO) activities were found to be increased. On the other hand, melatonin treatment reversed all the functional and biochemical changes. The present results demonstrate that Mel ameliorates ischemic heart failure in rats. These observations highlight that melatonin is a promising supplement for improving defense mechanisms in the heart against oxidative stress caused by heart failure.
  • PublicationMetadata only
    Antioxidant and anti-inflammatory effects of curcumin against hepatorenal oxidative injury in an experimental sepsis model in rats
    (2013-11-01T00:00:00Z) SAVCUN, Gulay Yilmaz; OZKAN, Erkan; DULUNDU, ENDER; TOPALOGLU, Umit; Sehirli, Ahmet Ozer; Tok, Olgu Enis; ERCAN, FERİHA; ŞENER, GÖKSEL; TOK, OLGU ENİS
    BACKGROUND: To investigate the effects of curcumin, an antioxidant and anti-inflammatory agent, on free oxygen radicals and lipid peroxidation in an experimental sepsis model, as well as to determine the role of curcumin in preventing hepatorenal tissue damage caused by sepsis.
  • PublicationMetadata only
    Correlation between the mechanical and histological properties of liver tissue
    (2014-01-01) Yarpuzlu, Berkay; Ayyildiz, Mehmet; Tok, OLGU ENİS; Aktas, Ranan Gulhan; Basdogan, Cagatay; TOK, OLGU ENİS
    In order to gain further insight into the mechanisms of tissue damage during the progression of liver diseases as well as the liver preservation for transplantation, an improved understanding of the relation between the mechanical and histological properties of liver is necessary. We suggest that this relation can only be established truly if the changes in the states of those properties are investigated dynamically as a function of post mortem time. In this regard, we first perform mechanical characterization experiments on three bovine livers to investigate the changes in gross mechanical properties (stiffness, viscosity, and fracture toughness) for the preservation periods of 5, 11, 17, 29, 41 and 53 h after harvesting. Then, the histological examination is performed on the samples taken from the same livers to investigate the changes in apoptotic cell count, collagen accumulation, sinusoidal dilatation, and glycogen deposition as a function of the same preservation periods. Finally, the correlation between the mechanical and histological properties is investigated via the Spearman-s Rank-Order Correlation method. The results of our study show that stiffness, viscosity, and fracture toughness of bovine liver increase as the preservation period is increased. These macroscopic changes are very strongly correlated with the increase in collagen accumulation and decrease in deposited glycogen level at the microscopic level. Also, we observe that the largest changes in mechanical and histological properties occur after the first 11-17 h of preservation. (C) 2013 Elsevier Ltd. All rights reserved.
  • PublicationMetadata only
    Mechanisms of the effects of Erythropoietin in wound healing: A morphologic study.
    (2012-01-01T00:00:00Z) Aktas, R. G.; Guven, A.; Ozacmak, H. S.; Ozacmak, V. H.; Ickin, M.; TOK, OLGU ENİS; Oktayer, A. G.; TOK, OLGU ENİS
  • PublicationMetadata only
    The Impact of Unilateral Experimental Rat Varicocele Model on Testicular Histopathology, Leydig Cell Counts, and Intratesticular Testosterone Levels of Both Testes
    (2013-06-01T00:00:00Z) OZTURK, Metin Ishak; KOCA, Orhan; KELES, Muzaffer Oguz; Haklar, Gonca; Baykan, Ozgur; ERCAN, FERİHA; Tok, OLGU ENİS; KARAMAN, Muhammet Ihsan; TOK, OLGU ENİS
    Purpose: Varicocele, most treatable pathologic condition in male infertility, exerts unfavorable effects on testicular ultrastructure via various mechanisms. In this study we aimed to demonstrate adverse effects of varicocele on both testes.
  • PublicationMetadata only
    Actin distribution in HepG2 cell-spheroids: A fluorescence microscopic study/
    (2012-01-01T00:00:00Z) Aktas, R. G.; KARAHUSEYINOGLU, S.; TOK, OLGU ENİS; Karabork, M.; Yucel, D.; TOK, OLGU ENİS
  • PublicationMetadata only
    Effects of beta-glucan on protection of young and aged rats from renal ischemia and reperfusion injury
    (2016-01-01) ESREFOGLU, MUKADDES; Tok, OLGU ENİS; AYDIN, M. S.; OZER, O. F.; SELEK, S.; Iraz, M.; EŞREFOĞLU, MUKADDES; TOK, OLGU ENİS; ÖZER, ÖMER FARUK; SELEK, ŞAHABETTİN
    BACKGROUND: Ischemia reperfusion injury is one of the leading causes of acute renal failure which is a common clinical event leading to development of chronic kidney disease and a high mortality; especially in elderly people. beta-glucans are glucose polymer groups with free-radical scavenger, macrophage activator, and immune defense inducer functions. We designed this study to determine the possible protective effects of beta-glucan against renal ischemia reperfusion injury comparatively in young and aged rats.
  • PublicationMetadata only
    The effect of the electromagnetic waves emitted by mobile phones on the testis morphology of rats.
    (2013-08-01) TOK, OLGU ENİS; ERCAN, Feriha; TOK, OLGU ENİS