Yazar "Tuncdemir, Matem" seçeneğine göre listele

Listeleniyor 1 - 6 / 6
  • Küçük Resim Yok
    Yayın
    AR-A014418 as a glycogen synthase kinase-3 inhibitor: Anti-apoptotic and therapeutic potential in experimental spinal cord injury
    (ELSEVIER DOYMA SL, 2013) Tuncdemir, Matem; Yildirim, Aziz; Karaoglan, Alper; Akdemir, Osman; Ozturk, Melek
    Objectives: We aimed to investigate the effects of AR-A014418, a strong inhibitor specific to GSK-3beta, on neuronal apoptosis and neuroprotection in the traumatic SCI model. Materials and methods: In this study, three groups were generated from 36 Wistar rats; (1) control, (2) spinal cord trauma group created by clip compression technique after laminectomy, and (3) AR-A014418 (4mg/kg, i.p., DMSO) treatment group after laminectomy and spinal cord trauma. The TUNEL assay for apoptosis detection, immunohistochemical staining for bax and TGF-beta were applied in spinal cord tissues. For light microscopic examination, necrotic, and apoptotic cells were counted, and PMNL counting was applied to detect inflammation. Functional recovery was tested by field locomotor test in the 3rd and 7th days following surgery. Results: In the trauma group, diffuse hemorrhage, cavitation, necrosis and edematous regions, degeneration in motor neurons and leukocyte infiltration were observed in gray matter. In the AR-A014418-treated groups, healthy cells were observed in more places compared to the trauma groups, however, cavitation, hemorrhagic, and edematous areas were seen in gray matter. In the AR-A014418-treatment groups, the number of apoptotic cells in the 3rd and 7th days (respectively; p<0.05, p<0.01), were significantly decreased compared to the trauma groups, as were the levels of bax (p<0.01) and TGF-beta 1 immunoreactivity. Results of the locomotor test were significantly increased in the treatment group (p<0.001) as compared to the trauma group. Conclusions: In this experimental spinal cord trauma model study neural apoptosis was significantly triggered in secondary damage developed after trauma, however, neurological healing was expedited by preventing mitochondrial apoptosis and reducing the inflammation by the potent inhibitor AR-A014418, which is GSK-3beta selective. 2011 Sociedad Espanola de Neurocirugia. Published by Elsevier Espana, S.L. All rights reserved.
  • Küçük Resim Yok
    Yayın
    The Effects of Difumarate Salt S-15176 after Spinal Cord Injury in Rats
    (KOREAN NEUROSURGICAL SOC, 2015) Erdogan, Hakan; Tuncdemir, Matem; Kelten, Bilal; Akdemir, Osman; Karaoglan, Alper; Tasdemiroglu, Erol
    Objective : In the present study we analyzed neuroprotective and antiapoptotic effect of the difumarate salt S-15176, as an anti-ischemic, an antioxidant and a stabilizer of mitochondrial membrane in secondary damage following spinal cord injury (SCI) in a rat model. Methods : Three groups were performed with 30 Wistar rats; control (1), trauma (2), and a trauma+S-15176 (10 mg/kg i.p., dimethyl sulfoxide) treatment (3). SCI was performed at the thoracic level using the weight-drop technique. Spinal cord tissues were collected following intracardiac perfusion in 3rd and 7th days of posttrauma. Hematoxylin and eosin staining for histopatology, terminal deoxynucleotidyl transferase dUTP nick end labeling assay for apoptotic cells and immunohistochemistry for proapoptotic cytochrome-c, Bax and caspase 9 were performed to all groups. Functional recovery test were applied to each group in 3rd and 7th days following SCI. Results : In trauma group, edematous regions, diffuse hemorrhage, necrosis, leukocyte infiltration and severe degeneration in motor neurons were observed prominently in gray matter. The number of apoptotic cells was significantly higher (p<0.05) than control group. In the S-15176-treated groups, apoptotic cell number in 3rd and 7th days (p<0.001), also cytochrome-c (p<0.001), Box (p<0.001) and caspase 9 immunoreactive cells (p<0.001) were significantly decreased in number compared to trauma groups. Hemorrhage and edema in the focal areas were also noticed in gray matter of treatment groups. Results of the locomotor test were significantly increased in treatment group (p<0.05) when compared to trauma groups. Conclusion : We suggest that difumarate salt S-15176 prevents mitochondrial pathways of apoptosis and protects spinal cord from secondary injury and helps to preserve motor function following SCI in rats.
  • Küçük Resim Yok
    Yayın
    Hemostasis vs. epidural fibrosis?: A comparative study on an experimental rat model of laminectomy
    (TERMEDIA PUBLISHING HOUSE LTD, 2016) Erdogan, Hakan; Kelten, Bilal; Tuncdemir, Matem; Erturkuner, Salime Pelin; Uzun, Hafize; Karaoglan, Alper
    Aim: The aim of this study was to evaluate the histopathological and biochemical impact and effectiveness of two hemostatic agents, Ankaferd blood stopper (ABS) and Microporous Polysaccharide Hemospheres (MPH), on epidural fibrosis in an experimental rat laminectomy model. Material and methods: Twenty adult Wistar albino rats were divided into MPH-treated (n = 6), ABS-treated (n = 6) and control (n = 8) groups. Laminectomy of the lumbar spine was performed in all animals and treatment groups were exposed to MPH and ABS while closure was applied in control group as per usual. Epidural fibrosis was evaluated in all groups macroscopically, histopathologically, biochemically and with electron microscopy four weeks later. Results: Statistically, it was found that MPH-treated group had significantly less epidural fibrosis compared to ABS-treated and control groups. Conclusion: We compared two hemostatic agents for their propensity to cause adhesions in the present study. Our results show that MPH significantly reduces epidural scar formation and dural adhesion in a rat model of laminectomy while ABS increases postoperative fibrosis. (C) 2016 Polish Neurological Society. Published by Elsevier Sp. z o.o. All rights reserved.
  • Küçük Resim Yok
    Yayın
    Melatonin with 1,25-Dihydroxyvitamin D3 Protects against Apoptotic Ischemia-Reperfusion Injury in the Rat Kidney
    (INFORMA HEALTHCARE, 2012) Sinanoglu, Orhun; Sezgin, Gulbuz; Ozturk, Guler; Tuncdemir, Matem; Guney, Sevin; Aksungar, Fehime Benli; Yener, Nese
    This study was designed to evaluate the preventive role of melatonin (Mel) and 1,25-dihydroxyvitamin D3 (VD3) in biochemical and apoptotic events leading to tissue injury and renal dysfunction after ischemia-reperfusion (I/R). Thirty male Wistar rats were divided into five groups: sham-operated, I/R, Mel + I/R, VD3 + I/R, and Mel + VD3 + I/R. The rats were intraperitoneally administered with Mel (10 mg/kg), VD3 (0.5 mu g/kg), or Mel (10 mg/kg) plus VD3 (0.5 mu g/kg) each day at 1 week prior to ischemia. Right nephrectomy was initially performed and left renal I/R injury was induced by 45 min of bilateral renal ischemia followed by 45 min of reperfusion. After reperfusion, kidneys and blood were obtained for histopathologic and biochemical evaluation. Mel and VD3 had an ameliorative effect on biochemical parameters such as serum creatinine, blood urea nitrogen, alanine aminotransferase, aspartate aminotransferase, and apoptosis (caspase-3 and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling staining) in the kidneys against renal I/R injury in rats. Additionally, VD3 combined with Mel significantly reduced apoptotic and histological alterations when compared with Mel or VD3 alone. This preventive effect on renal tubular apoptosis was remarkable when Mel was combined with VD3.
  • Küçük Resim Yok
    Yayın
    Pentoxifylline Inhibits Epidural Fibrosis in Post-Laminectomy Rats
    (INT SCIENTIFIC LITERATURE, INC, 2016) Kelten, Bilal; Erdogan, Hakan; Antar, Veysel; Sanel, Selim; Tuncdemir, Matem; Kutnu, Muge; Karaoglan, Alper; Orki, Tulay
    Background: The aim of this experimental study was to investigate the effectiveness of intramuscular pentoxifylline in the prevention of postoperative fibrosis. Material/Methods: We divided 16 adult Wistar albino rats into 2 equal groups: treatment and control. Both groups underwent L1 vertebral total laminectomy to expose the dura. The intramuscular treatment group received pentoxifylline. Four weeks later, epidural fibrosis was studied in both groups using electron microscopy, light microscopy, histology, biochemistry, and macroscopy. Results: The evaluation of epidural fibrosis in the 2 groups according to macroscopic (p<0.01) assessment and light microscopy revealed that epidural scar tissue formation was lower in the treatment group compared to the control group (p<0.001) and the number of fibroblasts was also decreased significantly in the pentoxifylline-treated group (p<0.05). More immature fibers were demonstrated in the treatment group by electron microscopy in comparison with the control group. In biochemical analysis, a statistically significant decrease was detected in hydroxyproline, which indicates fibrosis and myeloperoxidase activity, and shows an inflammatory response (P<0.001). Conclusions: Systemic pentoxifylline application prevents postoperative epidural fibrosis and adhesions with various mechanisms. Our study is the first to present evidence of experimental epidural fibrosis prevention with pentoxifylline.
  • Küçük Resim Yok
    Yayın
    Protective Effect of Melatonin and 1,25-Dihydroxyvitamin D3 on Renal Ischemia-Reperfusion Injury in Rats
    (INFORMA HEALTHCARE, 2013) Sezgin, Gulbuz; Ozturk, Guler; Guney, Sevin; Sinanoglu, Orhun; Tuncdemir, Matem
    Ischemia-reperfusion (I/R) injury induces the generation of reactive oxygen species (ROS) which affect many organs. This study was designed to investigate the roles of melatonin and 1,25-dihydroxyvitamin D-3 (VD3) on renal I/R injury. Thirty male Wistar albino rats were divided into five groups: group 1, control; group 2, right nephrectomy (RN) + I/R in the contralateral kidney; group 3, melatonin + RN + I/R; group 4, VD3 + RN + I/R; and group 5, melatonin + VD3 + RN + I/R. Melatonin (10 mg/kg), VD3 (0.5 mu g/kg), and melatonin plus VD3 were injected intraperitoneally for 7 days before renal I/R. After 7 days, right nephrectomy was initially performed and left renal artery was clamped for 45 min. After 45-min reperfusion, the serum and kidney tissue samples were obtained for assays. Melatonin and VD3 had an ameliorative effect on biochemical parameters such as serum creatinine (SCr) and blood urea nitrogen (BUN). Renal tissue malondialdehyde (MDA), glutathione (GSH), nitric oxide (NO) levels, and superoxide dismutase (SOD) activity were determined. Renal I/R decreased the kidney tissue GSH levels and SOD activity and increased the NO levels as compared with control group. However, melatonin and VD3 and melatonin plus VD3 treatment significantly increased the tissue GSH levels and SOD activity and decreased the NO levels compared with those of I/R group. Meanwhile, MDA levels were not different between the control and I/R groups. But, MDA levels decreased in all treated groups compared to I/R and control groups. These data support that melatonin and VD3 have beneficial effects on renal injury.