Browsing by Author "Sayin, M"
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Item Effect of sodium phenytoin concentration on neural tube development in the early stages of chicken embryo developmentTemiz, C; Temiz, P; Demirel, A; Sayin, M; Umur, AS; Özer, FDAnimal and human research has shown that anticonvulsants are teratogens and pose a risk of causing fetal malformations. In various studies, the teratogenic effects of sodium phenytoin (PTH) in several systems have been investigated. Toe and finger, renal, and even facial malformations have been described in the literature. However, there is debate about whether the true risk of teratogenesis is lower or higher than previously reported for PTH. There is also little published information on the effect of this agent on neural tube closure in an embryological model. In this study, 0.1 mL of three different concentrations of PTH solution (mg/mL: 1, 3, 5) or vehicle was applied under the embryonic disc of specific pathogen-free Leghorn chicken embryos after 24 hours' incubation. Incubation was continued until 72 hours of maturation. At 72 hours, all embryos were evaluated macroscopically and microscopically. There were serious neural tube closure defects in the embryos administered large amounts (0.5 mg) of PTH, but doses of 0.1 mg (subtherapeutic concentration for humans) and 0.3 mg (therapeutic concentration for humans) produced no statistically significant defects (p = 0.05). The difference between the defects in the high concentration group and the other three groups was statistically significant. In our study PTH administered in a strict concentration regimen produced a lower level of neural tube closure-related defects than previously reported. (C) 2008 Elsevier Ltd. All rights reserved.Item Effect of Cepea Extract-Heparin and Allantoin Mixture on Epidural Fibrosis in a Rat Hemilaminectomy ModelTemiz, C; Temiz, P; Sayin, M; Ucar, KAIM: Epidural fibrosis following a laminectomy procedure is a serious problem that results in failed back surgery syndrome. A serious number of manuscripts have explained its possible mechanism and results but no effective preventive surgical technique or treatment is currently present. MATERIAL and METHODS: We used a rat hemilaminectomy model at lumbar fourth level. In the treatment group (n:10), the hemilaminectomy sites were filled with cepea extract-allantoin and heparin mixture as sterile cream form. In the second group, the same surgical procedure was performed and the site was filled with physiological saline. All animals were terminated after 6 weeks and laminectomy sites removed en-bloc. Epidural fibrosis was evaluated and compared using semi-quantitative histopathological scoring scales. RESULTS: In the physiological saline group, the fibrosis score was 10.3 points and 90% of the subjects had acute inflammatory reaction, 80% chronic inflammatory reaction and 100% showed bone destruction and reparation process. In the cepea extract group, these values were fibrosis score 4.2 points, 0% acute inflammatory reaction, 33.3% chronic inflammatory reaction and 10% bone destruction and reparation process, respectively. CONCLUSION: This study showed that aloe cepea extract-allantoin and heparin mixture diminished epidural scarring formation effectively with decreased scores of acute and chronic inflammation, compared to the physiological saline solution group.Item Histologic Changes At The Intervertebral Disc Tissue After Laser NucleotomyÖsün, A; Samancioglu, A; Temiz, P; Temiz, C; Sayin, MMinimally invasive surgical techniques have become widely used for lumbar disc disease. Each of these techniques have a different physical effect in terms of retracting the prolapsed disc tissue and decompressing the adjacent nerve root by reducing the intradiscal pressure. Various types of laser generators with different wave lengths and electrode systems have been used for percutaneous laser disc decompression (PLDD). There are numerous studies regarding the clinical effectiveness of PLDD but histologic parameters which can prove the effectivity are few. Three patients with L4-5 disc prolapsus had undergone open microdiscectomy three months after PLDD because of the unsatisfactory results. The disc tissues were evaluated histologically. Fibrous fibrillary degeneration, integrity deformation of the fibres and chondrocyte proliferation were seen at the site of the microdiscectomy tissue. Previously laser irradiated disc materials had more severe fibrillary degeneration and the chondroid component degeneration was significant. In addition, degenerative calcification and massive necrosis of the chondrocytes were seen. Changes in fibronectin, tissue inhibitors of metalloproteinases (TIMP) and matrix metalloproteinases (MMPs) of the disc tissue were examined with immunohistochemical dyes. As a result, we found that PLDD causes a decrease in the water content of the disc tissue, hyaline degeneration, fibrillary destruction and chondrocyte depletion. Immunostaining showed that the extracellular matrix was effected, the metalloproteinase activity and protein compound of the extracellular matrix had changed. The findings were discussed in light of the literature.Item Does the Anti-Migraine Drug Rizatriptan Affect Early Neural Tube Development in Chick Embryos?Sayin, M; Gurgen, GS; Sayin, SS; Guvenc, G; Yuceer, NAIM: To investigate the impact of rizatriptan on neural tube development using early chick embryos as a model organism. MATERIAL and METHODS: A total of 36 pathogen-free Leghorn chicken eggs were selected and categorized in three groups: sham, therapeutic, and supra-therapeutic. After 24 hours, the eggs were opened and injected with sterile drugs, and then reclosed using plastic tape. After a period of 72 hours, the eggs were opened and assessed using the Hamburger-Hamilton chick embryology classification method. TUNEL staining was used to identify apoptosis, and hematoxylin-eosin staining was used to investigate neural tube closure. RESULTS: Treatment with rizatriptan significantly slowed down neural tube development. The supra-therapeutic group showed neural tube closure defects. CONCLUSION: Rizatriptan had a negative effect on neural tube closure. Further research is needed to identify a safe and effective drug for treating migraines during pregnancy.Item The dose-dependent neuroprotective effect of alpha-lipoic acid in experimental spinal cord injurySayin, M; Temiz, P; Var, A; Temiz, CBackground and purpose: Free radical production after spinal cord injury (SCI) plays an important role in secondary damage. The aim of this study was to investigate neuroprotective effects of the powerful antioxidant alpha-lipoic acid (ALA) in a spinal cord clip compression injury model. Material and methods: Fifty-six Sprague-Dawley rats, weighing between 210 and 300 g, were randomly divided into seven groups. Spinal cord injury was performed by an aneurysm clip placed extradurally at the level of T9. Group 1 (sham) received laminectomy only. Group 2 (control) received SCI; Group 3 received 30 mg/kg of methylprednisolone sodium succinate (MPSS); Groups 4, 5, 6 and 7 received ALA at doses of 50, 100, 150, 200 mg/kg, respectively, via the intraperitoneal route immediately after SCI. The rats were neurologically tested 24 hours after trauma. Spinal cord samples from injury sites were harvested for measurement of lipid peroxidation products and histopathological evaluation. Results: Spinal cord malonyldialdehyde levels of rats in treatment groups decreased after administration of ALA. The difference between the trauma group and groups receiving MPSS-ALA was statistically significant. The difference between the ALA (50, 100, 150 mg/kg) and MPSS groups was insignificant. Group 7 (ALA 200 mg/kg) was excluded from the study because of the possible toxic effect. Alpha lipoic acid and MPSS had similar effects on spinal cord injury in terms of lipid peroxidation, neurological recovery and histopathological changes. Conclusions: Alpha lipoic acid at a dose range of 50-150 mg/kg is as effective as MPSS (30 mg/kg) in neuroprotection after SCI. Further, more detailed experimental studies are needed to determine the effects of ALA on the detrimental results of secondary SCI before its use in humans.Item Apoptosis seems to be the major process while surface and neural ectodermal layers detach during neurulationSelcuki, M; Vatansever, S; Umur, AS; Temiz, C; Sayin, MObjective The aim of this study is to demonstrate the process of detaching neural and surface ectodermal layers soon after the neurulation completes. Materials and methods Specific pathogen-free chicken egg embryos were used to investigate the neurulation procedure. Ten eggs were saved as controls. The other ten eggs were opened at the 30th hour of embryo development and cultured with Z-VAD-FMK (peptide caspase inhibitor) to investigate the results of the apoptosis inhibition. Embryos were placed and developed up to 48 h in the culture medium. To detect apoptotic cells between neural and surface dermal layers, immunoreactivity of p53 and terminal uridine deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay were used. Results While the control group shows positive immunoreactivity of p53 and TUNEL-positive apoptotic cells at the site where the neural folds detach from the surface ectoderm, no TUNEL activity and no detachment were detected in the apoptosis-inhibited group. Conclusion As inhibition of apoptosis prevented the detachment of the neural and surface ectodermal layers from each other at the end of the neurulation, inhibition of apoptosis seemed to cause a considerable embryological error accounted for congenital dermal sinus tractus maldevelopment.Item The location of the obturator nerve: a three-dimensional description of the obturator canalKendir, S; Akkaya, T; Comert, A; Sayin, M; Tatlisumak, E; Elhan, A; Tekdemir, ISatisfactory analgesia cannot be achieved in every obturator nerve block. To attempt to improve the success rate of obturator nerve block, this study describes the detailed anatomy of the obturator region and canal. Eleven (5 female and 6 male) cadavers, totally 22 sides were dissected. Anatomical positions of the structures entering and leaving the canal were defined. The position of the obturator nerve and its branches and their relation with the obturator artery, vein, and with the internal iliac and femoral veins were investigated. A mould of the canal and a model were created. Detailed measurements were performed on the cadavers and models. The obturator canal was in the shape of a funnel compressed from superior to inferior, with anterior and posterior openings. At the entrance of the canal, the nerve lay superiorly; the artery was in the middle, and the vein lay inferiorly. The obturator nerve ran close to the lateral wall of the obturator canal. The distance of lateral wall of obturator canal to the median plane was 41.4 +/- 1.1 mm After leaving the canal, the nerve lay laterally while the anterior branch of the artery was medial. A venous plexus lay between the two structures. The presence of the branches of the obturator artery and vein alongside the obturator nerve may increase the risk of injury to these structures during anaesthetic procedures. The anterior division of the obturator nerve has a close relationship with these vessels. To provide complete analgesia, the obturator nerve should be blocked in the obturator canal or at its external orifice.Item Local Tissue Electrical Resistances in Transpedicular Screw Application in the Thoracolumbar RegionTuran, Y; Sayin, M; Yurt, A; Yilmaz, T; Ozer, FD; Temiz, CAIM: To determine local tissue electrical resistance differences generated during a screw pass from the pedicle to another tissue rather than determining all individual electrical tissue resistance values. MATERIAL and METHODS: We attempted to measure electrical resistance values of regional tissues in addition to fluoroscopic imaging during application of fixation via a transpedicular screw. We also attempted to detect local tissue electrical resistance alterations in case of malposition of the screw inside the pedicle. For this purpose, local tissue electrical resistances of 10 transpedicular tracks opened with standard track openers bilaterally in 5 vertebrae, and of spinal cord accessed by puncturing the medial walls of three vertebrae in a cadaver were measured. These resistance differences were not only measured in human cadaveric tissue but also in 36 pedicles belonging to a total of 18 vertebrae between Th 1-S1 vertebrae of a sheep cadaver. Both medial and lateral walls were drilled to measure local tissue resistance differences in a sheep cadaver. RESULTS: Our results indicated that local tissue electrical resistance changes were statistically significant in both human and sheep cadaver. CONCLUSION: It is possible to prevent screw malposition using a simple and cheap electrical resistance measurement. Local tissue electrical resistance measurement during transpedicular screw insertion is a safe, simple, cheap, and practical method.Item ACE genotype may have an effect on single versus multiple set preferences in strength trainingColakoglu, M; Cam, FS; Kayitken, B; Cetinoz, F; Colakoglu, S; Turkmen, M; Sayin, MA polymorphic variant of the human angiotensin converting enzyme (ACE) gene was identified. The 'D' (rather than `I') variant was associated with improvements in strength related to physical training. We set out to determine whether the response to different patterns of strength training night also differ. Ninty-nine Caucasian male non-elite athletes were randomly allocated into one of three groups: 31 nontraining/control (CG: 31), single-set (SSG: 35) and multiple-set (MSG: 33). SSG and MSG trained three times a week for 6 weeks. Both training groups were underwent a strength-training program with two mesocycles (12-15 repetition maximum (RM) and 8-12 RM mesocycles). One RM loads in half squat and bench press were assessed before training and after the first and second mesocycles. ACE polymorphisms analysed by polymerase chain reaction (PCR) methods. Subjects with ACE II genotype in the MST group had improved strength development in 12-15 RM, while SST and MST groups had similar gains in 8-12 RM. Subjects with ACE DD genotype in both the SSG and the MSG had similar benefits from both 12-15 RM and 8-12 RM. Strength gains for subjects with ACE ID genotype in the SSG were similar to MSG gains in response to 8-12 RM loads but not with 12-15 RM loads. Additionally, subjects with DD genotype had superior strength gains in both strength training groups. Tailoring strength training programmes (single-set vs. multiple set) according to the athlete's ACE genotype may be advantageous.