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Öğe Anatomical Variations of the Cystic Duct in Turkish Population and their Association with Biliary Track Stone(Coll Physicians & Surgeons Pakistan, 2020) Tastemur, YasarObjective: To evaluate the anatomy and various anatomical variations of the cystic duct and their association with the stones in the biliary tract in the Turkish population. Study Design: Observational study. Place and Duration of Study: Sivas Cumhuriyet University Hospital between November 2017 and August 2019. Methodology: Patients who had undergone MRCP procedures at the study centre were assessed retrospectively. MRCP images were used to evaluate the variations of the cystic duct. Association with the stones in the biliary tract was noted with p<0.05 as significant. Results: Three thousand MRCPs were evaluated. Among the 930 patients included in the study, 408 were males (43.9%), 61.9 +/- 17 years, while 522 were females (56.1 %), 57.1 +/- 19.2 years. The most common variation was lateral insertion in 372 patients (40%), medial insertion in 226 patients (24.3%), and high insertion in 137 patients (14.7%). Lateral, medial, high insertions (all p <0.001), parallel course of the cystic duct (p <0.001), low medial (p=0.024), and posterior insertion (p=0.003) were significantly associated with the calculi in the biliary tract. The highest coexistence frequency was at anterior, posterior, and low medial insertion variation groups, at 25%, 23.8%, and 25%, respectively. Conclusion: Preoperative information of anatomical variations of the cystic duct is not only important for operative planning; but some variations are significantly associated with the cholelithiasis and/or choledocholithiasis.Öğe The Effect of Dopamin(2) Receptor on Oxytocin-Induced Analgesia in Rats(KARGER, 2018) Tastemur, Yasar…Öğe Lycopene induces antiproliferative effects through apoptosis, autophagy, and oxidative DNA damage in the HeLa cells(Taylor & Francis Ltd, 2024) Parlak, Mesut; Joha, Ziad; Yulak, Fatih; Mendil, Ali Sefa; Tastemur, YasarBackground: This study explores the role of apoptosis, autophagy, and oxidative DNA damage in influencing the cytotoxic impact of lycopene on HeLa cells. Material and methods: Cell viability following exposure to varying lycopene concentrations was determined using an XTT assay. ELISA measured key cell death proteins (Bax, BCL-2, etc.), while immunofluorescence staining visualized LC3 beta (autophagy) and 8-oxo-dG (DNA damage). Results: Lycopene significantly killed HeLa cells in a dose-dependent way (IC50 = 10 mu M). Subsequent examinations conducted with the IC50 dose of lycopene demonstrated a notable elevation in the expression levels of apoptotic proteins, such as cleaved caspase 3, cleaved PARP, and Bax (p < 0.001). Additionally, treatment with this substance led to an increase in the levels of 8-oxo-dG (p < 0.001), a widely acknowledged biomarker indicative of oxidative DNA damage. Furthermore, a significant rise (p < 0.05) in LC3 beta protein levels, a well-established indicator of autophagy activation, was noted. Conclusion: This study suggests lycopene's potential to fight cervical cancer by triggering programmed cell death (apoptosis) and cellular self-digestion (autophagy). These findings highlight lycopene as a promising candidate for future cervical cancer treatments.Öğe Positive effects of angiotensin-converting enzyme (ACE) inhibitor, captopril, on pentylenetetrazole-induced epileptic seizures in mice(Pharmacotherapy Group, 2020) Tastemur, Yasar; Gumus, Erkan; Ergul, Merve; Ulu, Mustafa; Akkaya, Recep; Ozturk, Aysegul; Taskiran, Ahmet SevkiPurpose: To evaluate the effects of an angiotensin-converting enzyme (ACE) inhibitor, captopril, on pentylenetetrazole (PTZ)-induced seizures and post-seizure hippocampal injury. Materials: Thirty-five male Balb-c mice weighing 30 - 33 g were divided into control, saline PTZ, s(erum ;physiologic 1 ml/kg as solvent), positive control (valproic acid 200 mg/kg), captopril (25 mg/kg/day for 7 days), and captopril (50 mg/kg/ day for 7 days) groups. PTZ (60 mg/kg) was administered thirty minutes after medication administration to induce epileptic seizures. The animals were observed for 30 min to record Racine stages, the time of the first myoclonic jerk (FMJ), and the occurrence of the first generalized tonic-clonic seizure (GTCS). Cornu Ammonis (CA)1, CA2, CA3, and the dentate gyrus (DG) of the hippocampus underwent histopathological examinations. The levels of total oxidant status (TOS), oxidative stress markers (total antioxidant status, TAS), and oxidative stress index (OSI) were measured in the brain tissue. Results: Compared to PTZ group, 25 mg/kg captopril decreased seizure scores and delayed FMJ and GTCS (p < 0.05). Histopathological assessment demonstrated that both 25 and 50 mg/kg captopril alleviated neuronal injury in CA1, CA2, CA3, and DG compared to PTZ (p < 0.05). Also, TOS and OSI levels in the brain tissue were reduced by both 25 and 50 mg/kg doses of captopril (p < 0.05). Conclusion: Captopril favorably improves epileptic seizure parameters and acts against post-seizure neuronal injury in the hippocampus. Captopril may be a drug of choice in epileptic individuals with hypertension.Öğe Protective effects of lamotrigine and vitamin B12 on pentylenetetrazole-induced epileptogenesis in rats(Academic Press Inc Elsevier Science, 2021) Filiz, Ahmet Kemal; Gumus, Erkan; Karabulut, Sebahattin; Tastemur, Yasar; Taskiran, Ahmet SevkiEpileptogenesis is a process that includes molecular and cellular events that foster the establishment of hyperexcitable neuronal networks in the brain. Pentylenetetrazole (PTZ)-induced kindling model in rodents has added new information to the knowledge about the pathogenesis of epilepsy and potential targets of novel antiepileptic agents. Evidence from animal and human studies suggests that oxidative and inflammatory events may play important roles in the initiation and maintaining seizure activities. Vitamin B12 has beneficial effects on the nervous system and presents pleiotropic effects with antioxidant and anti-inflammatory aspects. In the present study, we aimed to test the hypothesis that vitamin B12 and their combination with lamotrigine prevents behavioral deficits, hippocampal damage, oxidation, and proinflammatory state during epileptogenesis. Male rats were subjected to PTZ-induced epileptogenesis and pretreated with vitamin B12 (50 mu g/kg) or Lamotrigine (LTG) (25 mg/kg) or B12 (50 mu g/kg) + LTG (25 mg/kg). Vitamin B12 and its combination with LTG suppressed epileptogenesis and improved the performance of rats in the passive avoidance test. In addition, Vitamin B12 and its combination with LTG decreased levels of total oxidative status (TOS), oxidative stress index (OSI), interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), and increased total antioxidant status (TAS) levels in the hippocampus and cerebral cortex. Furthermore, it reduced hippocampal neuronal damage. Current findings support the beneficial actions of vitamin B12 due to its antioxidative and anti-inflammatory properties during the course of disease. (C) 2021 Elsevier Inc. All rights reserved.Öğe The Relationship of the Posterior Cranial Fossa, the Cerebrum, and Cerebellum Morphometry with Tonsiller Herniation(KOWSAR PUBL, 2017) Tastemur, Yasar; Sabanciogullari, Vedat; Salk, Ismail; Sonmez, Muhittin; Cimen, MehmetBackground: Tonsillar herniation is a condition that manifests as herniation of the brain parts, originating from the hindbrain and progressing through the foramen magnum into the cervical vertebral canal. Although the etiology of tonsillar herniation is unclear, it has been suggested that it may be congenital or acquired. In particular, there is speculation that primary mesodermal insufficiency may affect the size of the posterior cranial fossa. Objectives: Our main objective is to perform measurements of the cranium, cerebrum, and cerebellum in order to clarify the etiology of tonsillar herniation. Patients and Methods: Magnetic resonance images were taken for 1,052 patients (629 females and 423 males) with no disease affecting the bones. Chiari malformation type I (CMI) was detected in 63 of the patients. The remaining 989 patients were considered to be the control group. The patients' mean age was 36.58 +/- 22.34 (1-94 years). Measurements were performed using midsagittal and axial T1 and T2 images. Nine parameters were used to evaluate cranium morphometry, while a further nine were used to evaluate cerebrum and cerebellum morphometry. The data collected were analyzed using SPSS version 14 statistics software, in addition to the t-test and the Mann-Whitney U test. The significance level was set at 0.05. Results: In individuals with tonsillar herniation, while the front-back diameter of the foramen magnum, the cerebellum height, and the sagittal diameter of the cerebellum increased, the maximum cranial height, supraocciput length, clivus length, and height of the posterior cranial fossa decreased. Also, in the case of all age groups, there was no statistically significant difference between the healthy controls and the people with tonsillar herniation in terms of tentorial slope angle. The mean herniation value was 4.85 +/- 3.09mmin those with tonsillar herniation. Conclusion: Our results concerning cranium morphometry support the theory that hypoplastic posterior cranial fossa due to mesodermal insufficiency may play a role in the etiology of tonsillar herniation.Öğe Role of dopaminergic system in oxytocin analgesia: The missing part in a puzzle(Pharmacotherapy Group, 2020) Tastemur, Yasar; Taskiran, Ahmet Sevki; Altun, Ahmet; Filiz, Ahmet Kemal; Gulmez, Kader; Cimen, Kaan; Ozdemir, ErcanPurpose: To investigate the analgesic effects of oxytocin (OT) and elucidate the role of dopaminergic system in its mechanisms. Methods: In this study, 72 male (n=6 for each group) 230-250 gr Wistar Albino rats were used. Firstly, dose studies were performed with 100 mu g/kg, 200 mu g/kg and 400 mu g/kg to determine the optimal analgesic effect of oxytocin. Optimal dose was found at 200 mu g/kg, and then animals were divided into nine groups: Saline, D1 agonist (SKF 38393; 0.1 mg/kg), D1 antagonist (SCH-23390; 0.1 mg/kg), D1 agonist + oxytocin, D1 antagonist + oxytocin, D2 agonist (Cabergoline; 0,5 mg/kg), D2 antagonist (Sulpride; 10 mg/kg), D2 agonist + oxytocin and D2 antagonist + oxytocin. Serum physiologic saline was given to the saline group and other drugs were administered intraperitoneally at the indicated doses. Tail-flick and hot-plate tests were used to measure analgesic effects. Analgesic tests were measured in 30 min-intervals (at 30th, 60th, 90th, and 120th min) and recorded in seconds. To evaluate maximum antinociceptive effect (% MPE), the tail-flick and hot-plate latencies were converted to the antinociceptive effectiveness Results: The results show that D1 antagonist SCH-23390 (0.1 mg/kg) and D2 agonist cabergoline (0.5 mg/kg) created strong analgesia while the D1 agonist SKF 38393 (0.1 mg/kg) and D2 antagonist sulpiride (10 mg/kg) did not have any analgesic effect. However, only D2 antagonist sulpiride blocked the analgesic effect produced by OT Conclusion: OT may be one of the primary agents participating in spinal analgesia, and the dopaminergic system is one of the central mechanisms of action for this important molecule. The dopaminergic system may also be one of the targets for 'descending' analgesic system.Öğe The contribution of non-drug factors to fetal malformation in anti-seizure-medication-treated pregnancy(Academic Press Inc Elsevier Science, 2021) Filiz, Ahmet Kemal; Gumus, Erkan; Karabulut, Sebahattin; Tastemur, Yasar; Taskiran, Ahmet SevkiPurpose: To assess the possible contribution of factors in additional to intrauterine anti-seizure medication (ASM) exposure in the occurrence of fetal malformation in women with ASM-treated epilepsy. Results: Logistic regression analysis showed that maternal age over 31 years, family histories of fetal malformation, and conception after assisted fertility treatment, and also dosage of valproate, carbamazepine, and topiramate, made statistically significant (P < 0.05) contributions to the fetal malformation rate in 2223 pregnancies in Australian women with epilepsy. The malformation rates were lower in pregnancies where the non-ASM-associated contributory factors were not present: statistically significantly so for all ASM-exposed pregnancies, and those pregnancies exposed to the more potent teratogenic drugs. Conclusion: It is important to consider the possible roles of identified, and also possible non-identified, non-ASM factors in relation to the occurrence of fetal malformations in the pregnancies of women with ASM-treated epilepsy. (C) 2021 Elsevier Inc. All rights reserved.Öğe The role of nitric oxide in anticonvulsant effects of lycopene supplementation on pentylenetetrazole-induced epileptic seizures in rats(Springer, 2021) Taskiran, Ahmet Sevki; Tastemur, YasarRecent studies have shown that natural antioxidant compounds have positive effects on the nervous system. Lycopene, the red pigment in tomatoes, is one of the potent natural antioxidants, and is used as supplementation because of its well-known health benefits. However, its effect on epileptic seizures and underlying mechanisms are still unclear. In this study, it was aimed to investigate the effect of lycopene on pentylenetetrazole-induced epileptic seizures in rats and to elucidate the nitric oxide pathway in this effect. In this study, thirty male Wistar albino rats were used. Animals were divided into five groups (n = 6 for each group) as control, saline (1 mL/kg/day serum physiologic), positive control (2 mg/kg/day diazepam), and lycopene (5 and 10 mg/kg/day) for ten days. Pentylenetetrazole (45 mg/kg) was given to induce a seizure in the tenth day except for the control. Passive avoidance test was carried out to evaluate memory function. Inducible nitric oxide synthase (iNOS), neuronal nitric oxide synthase (nNOS), and nitric oxide (NO) levels were measured in the cortex and hippocampal brain regions using the ELISA kits. Lycopene supplementation prolonged epileptic seizure onset times and reduced seizure stages. Besides, lycopene supplementation improved memory impairment after seizures. Moreover, lycopene significantly reduced the level of iNOS, nNOS, and NO in the brain. Lycopene supplementation significantly alleviated seizures and memory impairment. Its anticonvulsive effect could be associated with the nitric oxide pathway. Lycopene supplementation could be useful as a supportive therapeutic agent in epileptic patients.
