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Öğe Challenges associated with meningiomas with extracranial extension: A clinical study(2022) Genç, Ali; Akyuva, Yener; Kabataş, SerdarObjective: Surgical treatment of extracranial meningiomas is challenging. In this study, we present an illustrated case series to share our experience in the treatment of meningiomas with extracranial extension. Method: We retrospectively reviewed the data of 11 patients with meningiomas who underwent surgical treatment between 2008 and 2020. The intracranial and extracranial components were radiologically and intraoperatively confirmed for all patients. Results: The patients included seven men and four women with a mean age of 55.4 years. Most patients presented with facial disfigurement or asymmetrical skull growth. The most common symptom at presentation was headache. The most common location of the meningiomas was the frontal region and those of extracranial growth were the paranasal sinuses and parietal bone invasion. We recognized two distinct modalities of bone destruction: hyperostosis (n=3) and osteolysis (n=8). Pathological investigation revealed atypical features in six patients. Preoperative embolization was attempted in four patients but it proved to be difficult; proper embolization could be achieved only in one patient. The most commonly encountered challenges during surgery were large calvarial and cranial base defects due to bone erosion, dural defects, and managing the superior sagittal sinus with parietal tumors. Excessive blood loss was also of particular concern, which was managed using simple scalp clips, intraoperative transfusion, and other conservative approaches of tumor extensions into paranasal sinuses. No perioperative mortality occurred. Calvarial reconstruction was performed with polymethyl methacrylate cement where needed. Conclusion: Meningiomas with extracranial extension are surgically challenging but treatable. It contains fine neurosurgical trics in its treatment and follow-up.Öğe Challenges in the clinical and radiological differential diagnosis of cerebrovascular events and malignant primary brain tumors: reports from a retrospective case series(Turkish Neurosurgical Society, 2020) Civelek, Erdinç; Akyuva, Yener; Kaplan, Necati; Diren, Furkan; Boyalı, Osman; Kabataş, SerdarAIM: To reveal difficulties in differential diagnosis of some cases of cerebrovascular events (CVEs) and malignant primary brain tumors (MBTs) even a multidiciplinary evaluation in grand rounds. MATERIAL and METHODS: This study retrospectively analyzed the patient archives from January 2017–December 2019. The records of 572 patients discussed in these meetings were examined. A total of 8 patients having a challenge in differential diagnosis were detected. RESULTS: This study has included 8 cases in which neurology−neurosurgery−neuroradiology clinicians have difficulty in differentiating CVE and MBT. In the present study, three patients were evaluated with a preliminary diagnosis of hemorrhagic CVE in the emergency room. Since degradation products of hemoglobin have prevented advanced imaging methods to diagnose in two patients, these patients have been followed closely. The correct diagnosis could be made through the scan performed during control follow-ups The preliminary diagnosis of seven patients was CVE, but they received the MBT diagnosis during the follow-up. One patient was thought to have MBT initially; however, he/she was diagnosed with CVE after an advanced examination and close follow-up. CONCLUSION: Despite developing medical imaging methods and diagnostic studies, there are still some difficulties in making differential diagnosis of CVEs and MBTs. In some patients, further examination and imaging methods may be needed such as magnetic resonance imaging-spectroscopy (MRI-S), perfusion magnetic resonance imaging (Per-MRI), digital substratioangiography (DSA). Despite all these neuroradiological examinations and multidiciplinary evaluation, distinction between CVE and MBT may be difficult, and medicolegal problems may be encountered.Öğe Clostridium botulinum neurotoxin A inhibits DBTRG glioblastoma cell proliferation and TRPV1 channel signaling pathways(Suleyman Demirel University, 2020) Akyuva, YenerPrevalence of glioblastomas is high within the adult brain tumors and the proliferation of the glioblastomas was induced by excessive Ca2+ influx. Ca2+ permeable TRPV1 channel is gated by capsaicin and reactive oxygen species (ROS), although its activity was decreased in neurons by AMG and antioxidants. Clostridium botulinum neurotoxin A (BotxA) acted antioxidant action in several cells and its treatment modulated TRPV1 in neurons. Hence, treatment of BotxA may modulate glioblastoma cell proliferation and death via inhibition of TRPV1 in the DBTRG glioblastoma in vitro cell line model. The DBTRG cells were divided into three groups as control, BotxA (5 IU for 24 hours) and BotxA+TRPV1 channel blocker (AMG and 1 µM for 30 min). Intracellular Ca2+ response to TRPV1 activation was increased in the cells from capsaicin, although it was reduced by the BotxA and AMG. BotxA treatment decreased cell proliferation, although its treatment increased cell death (propidium iodide/Hoechst rate). In addition, BotxA decreased mitochondrial membrane depolarization levels, cytosolic and mitochondrial ROS generation in the cells. Their levels were further decreased in the BotxA+AMG group by the AMG treatment. The antiproliferative and neurotoxic effects of BotxA were shown to be exerted via modulation of oxidative stress and TRPV1 activation. BotxA could be used as an effective agent in the treatment of glioblastoma proliferation. © 2020 Suleyman Demirel University. All rights reserved.Öğe Complications of Cervical Disc Prosthesis Dislocation: A Retrospective Clinical Study(Galenos Yayincilik, 2021) Akyuva, Yener; Ozger, Ozkan; Urfali, Boran; Kaplan, Necati; Aykut, Ali MaksutObjective: The most commonly used method for the surgical treatment of cervical disc herniation (CDH) is anterior disc excision with Smith-Robinson's approach. Following the excision of pathological disc space, disc prosthesis is placed if a continuation of dynamic movement in the disc space is desired and a cervical cage is placed for the purpose of fusion. Cervical disc prosthesis seems superior to cervical cage; however, it is not suitable for every patient and can cause serious complications. Our study include data of patients who developed complications following the dislocation of cervical prosthesis and who were referred to our clinic. The aim of our study is to emphasize that the cervical prosthesis is not suitable for every patient and may cause serious complications. Methods: Data of the patients who were operated due to the diagnosis of CDH in other centers and underwent revision surgery for the development of cervical prosthesis dislocation between 2013 and 2020 were collected. Results: This study analysed the data of four male and three female patients. The median value of patient ages was 42 (28-53). Neck pain and swallowing difficulty were the most common reasons for admission to the clinic. Dislocation was found to develop after trauma in three patients. Anterior and posterior dislocations were found to develop in five and two patients, respectively. Seven patients underwent revision surgery. All these patients were found to have dislocations at the C5-6 level. Conclusion: The prosthesis to be placed in the surgical treatment of CDH should be determined based on the patient. Detailed information should be provided to the patient for whom cervical disc prosthesis is to be placed and prosthesis of the most appropriate size for disc space should be placed properly.Öğe EFFECT OF BALLOON KYPHOPLASTY TREATMENT FOR OSTEOPOROTIC VERTEBRAL FRACTURE ON SPINAL BALANCE(Gunes Kitabevi Ltd Sti, 2023) Yucel, Engin; Akyuva, YenerIntroduction: Osteoporotic vertebral fractures and spinal degeneration are common consequences of aging, and co-occurrence of these two pathologies can impair spinal balance leading to development of further deformities. The most common treatment measure for osteoporotic vertebral fractures is percutaneous balloon kyphoplasty which can potentially improve spinal balance along the sagittal and coronal planes. However, there is limited evidence in support of this issue to date.Materials and Methods: This study included 49 patients (27 males, 22 females) who were diagnosed with osteoporotic vertebral fracture. The patients were evaluated preoperatively and one year postoperatively using three-dimensional thoracolumbar computed tomography scans. The lumbar lordosis and sacral slope angle were used to assess the sagittal plane, while coronal plane assessment was carried out using Cobb's angle. The angle values before and after treatment were compared statistically.Results: The mean age of the study participants was 72.16 years (range: 61- 94 years), and 28.6% and 71.4% of the patients exhibited thoracic and lumbar vertebral fractures, respectively. Moreover, 19 patients exhibited spontaneous or minor traumatic vertebral fractures, and 16 patients diagnosed with degenerative scoliosis exhibited a significant improvement in Cobb's angle after treatment. The comparison of pre-and postoperative mean sacral slope and lumbar lordosis angles showed an increase in both values and these differences, although not statistically significant, in agreement with previous literature.Conclusion: Percutaneous balloon kyphoplasty has become an increasingly popular treatment measure for osteoporotic vertebral fracture due to its ability to effectively correct spinal imbalance in patients.Öğe Is there a correlation between dominant extremity and cervical disc herniation using machine learning methods?(Ondokuz Mayis Universitesi, 2023) Yücel, Engin; Akyuva, YenerWe aimed to investigate the possibility of determining the relationship between the dominant extremity and cervical disc herniation using a machine learning approach. A total of 561 patients diagnosed with cervical disc herniation were examined for dominant extremity, level and side of cervical disc herniation, and the nature of the herniation (calcified/soft). These patients formed the basis for a two-step machine learning system creation. The first step (included the data of 80% of the patients) focused on determining the type of cervical disc herniation by selecting the top five performing classification models out of 15 different models and tuning the hyperparameters. In the second step, the machine learning system was validated using data from a randomly selected subset of patients (20% of the patients). The study results showed that while most models performed well, the gradient boosting classifier was the most accurate (89.38%) for determining the herniated disc nature. However, for classifying the disc herniation direction, the models did not exhibit strong performance. Thus, machine learning can accurately identify the relationship between cervical disc herniation and dominant extremity with a high degree of accuracy. © 2023 Ondokuz Mayis Universitesi. All rights reserved.Öğe Lumbar Disc Herniation Might Spontaneously Regress, While NeuropathicPain Might Start: Retrospective Clinical Study(2020) Akyuva, Yener; Kaplan, Necati; Urfalı, Boran; Özger, Özkan; Civelek, Erdinç; Kabataş, Serdar; Serasrlan, YurdalLumbar disc herniation (LDH) is a common cause of low back pain and radicular pain. The aim of our study was to evaluate the regression of LDH in patients who are considered to require surgical treatment but prefer conservative treatment. Patients who presented between January 2018 and June 2020 and who did not accept the recommended surgical treatment following a diagnosis of LDH based on clinical and radiological findings were retrospectively reviewed. All 12 of the patients included in the study showed spontaneous regression of LDH during outpatient clinical follow-up. Our study included 12 patients (seven male and five female). The mean age was 46.5 (the youngest was 30 years old; the oldest was 70 years old). Regression was observed at the L2-L3 level in two patients (10%), at the L4-L5 level in four patients (40%), and at the L5-S1 level in six patients (50%). On the follow-up examination of all patients, the severity of their pain was evaluated with the Visual Analogue Scale, and all patients described a reduction in pain (min: 2, max: 8). Ten patients described radicular pain at the initial examination, eight patients received physical therapy and rehabilitation treatment before the follow-up examination, and nine patients described neuropathic pain at the follow-up examination. Spontaneous regression of LDH is rare. While conservative treatments provided partial improvement in the complaints of these patients, conservative treatments usually cannot prevent the development of neuropathic pain.Öğe Morphine Induces Apoptosis, Inflammation, and Mitochondrial Oxidative Stress via Activation of TRPM2 Channel and Nitric Oxide Signaling Pathways in the Hippocampus(Springer, 2020) Osmanloglu, Omer; Yldirim, Mustafa Kemal; Akyuva, Yener; Yildizhan, Kenan; Naziroglu, MustafaMorphine as an opioid is an important drug in the treatment of moderate to severe pain. Several stress factors via generation of nitric oxide (NO) and oxidative stress (OS) are responsible for the adverse effects of morphine-induced analgesia, addiction, and antinociceptive tolerance, including altered Ca(2+)concentration, inflammation, OS, and release of apoptotic factors. TRPM2 is a Ca2+-permeable cation channel and it is activated by OS and NO. Hence, adverse effect of morphine addiction may occur via the OS and NO-induced TRPM2 activation. Because of the unclear etiology of morphine-induced adverse effects in the hippocampus, investigating the involvement of TRPM2 and NO synthetase (NOS) activations in the treatment of morphine-induced OS, apoptosis, and neuroinflammation is a major challenge. The hippocampal neuron of TRPM2 wild-type (TRPM2-WT) and knockout (TRPM2-KO) mice were divided into control, morphine, NOS inhibitor (L-NAME) + morphine, and TRPM2 channel blockers (ACA and 2-APB) + morphine. The morphine-induced increases of apoptosis, neuron death, OS, lipid peroxidation, caspase-3 and caspase-9, neuroinflammatory cytokines (IL-1 beta, TNF-alpha, IL-6), and Ca(2+)levels in the hippocampal neuron of TRPM2-WT mouse were decreased by the L-NAME, ACA, and 2-APB treatments, although cell viability, neuron count, and reduced glutathione and glutathione peroxidase levels were increased by the treatments. However, the effects of morphine were not observed in the hippocampus of TRPM2-KO mice. Taken together, our data show that neurodegeneration adverse effects of morphine were induced by activation of TRPM2, and excessive generations of NO and OS. Thus, inhibition of TRPM2 may modulate morphine-induced neurodegeneration in the hippocampus.Öğe Morphine Induces Apoptosis, Inflammation, and Mitochondrial Oxidative Stress via Activation of TRPM2 Channel and Nitric Oxide Signaling Pathways in the Hippocampus (vol 17, pg 313, 2020)(Springer, 2020) Osmanlioglu, Haci Omer; Yildirim, Mustafa Kemal; Akyuva, Yener; Yildizhan, Kenan; Naziroglu, Mustafa[Abstract Not Available]Öğe Neuroprotective effect of carvacrol in an experimental cerebral ischemia and reperfusion rat model(Ondokuz Mayis Universitesi, 2022) Başaran, Mustafa; Öztanir, Mustafa Namık; Çıftçı, Osman; Başak Türkmen, Neşe; Akyuva, Yener; Önder, ArifThe Neuroprotective effect of carvacrol, which has anti-inflammatory and antioxidant effects, on infarcted cerebral tissue is present in literature, but this contribution was not sufficiently clarified in terms of biochemistry. It is aimed to investigate the effect of orally administered carvacrol on plasma and intraparenchymal levels of TBARS, GSH, SOD, CAT, GSH-Px, IL-1?, IL-4, and TNF-? after the formation of global ischemia in cerebral tissue. Four groups were formed, each containing ten Wistar albino rats. After anesthesia and analgesia, bilateral carotid communis arteries of rats in the first two groups were clamped for 15 minutes with aneurysm clips. Oral 50 mg/kg/day carvacrol was administered for 15 days to the first group (I/R+CRV) of these two groups in which cerebral ischemia-reperfusion (I/R) was established. On the other hand, %0,01 carboxymethylcellulose (CMC), which is a solvent of carvacrol, at a same volume of first group was administered orally for the same duration to the other group in which also I/R was established (I/R+CMC). In the other two groups in which ischemia was not induced, only carotid artery dissections were made and sutured again. In these two groups, 50 mg/kg/day of carvacrol was administered to the first group (CRV). The Same dose of CMC was administered to the second group (control group). After all these treatments, plasma was collected, and brain tissue was dissected from all groups at the end of the 15th day. Carvacrol can be included in the possible treatment regimen of cerebral stroke with the help of other studies that can be supported on this topic. © 2022 Ondokuz Mayis Universitesi. All rights reserved.Öğe Oxidative Stress and Biochemical Alterations in Patients with Head and Multiple Organ Traumas(Turkish Neurosurgical Soc, 2023) Akyuva, Yener; Nur, Gokhan; Deveci, Haci Ahmet; Guler, Songul KocabasAIM: To evaluate paraoxonase (PON), total antioxidant status (TAS), total oxidant status (TOS), high-density lipoproteins (HDL), CRP, AST, ALT, GGT, ALP levels in patients with head and multiple organ traumas.MATERIAL and METHODS: The study included 29 male patients undergoing treatment for head and multiple organ traumas. Blood sample analysis was performed on the first, third, and seventh days after trauma.RESULTS: The mean age, duration of hospitalization in the intensive care unit, and intubation period of the study sample was 45 years (range: 9 to 81 years), 4.29 days, and 2.94 days, respectively. One patient died, and 13 underwent surgical intervention. Comparison of PON, TAS, TOS, and CRP levels showed statistically significant differences between the first day and the third and seventh days, although no such differences were seen in HDL levels. A moderately positive correlation was observed between CRP/ AST, CRP/ALT and CRP/GGT, while a moderately negative correlation was seen between CRP/ALP.CONCLUSION: The findings of this study suggest that some oxidative parameters may play a significant role in the prognosis and follow-up of intensive care patients. Moreover, biochemical markers can provide important information about patient response to trauma.Öğe Resveratrol attenuates hypoxia-induced neuronal cell death, inflammation and mitochondrial oxidative stress by modulation of TRPM2 channel(Nature Portfolio, 2020) Akyuva, Yener; Naziroglu, MustafaHypoxia (HYPX) induced-overload Ca2+ entry results in increase of mitochondrial oxidative stress, inflammation and apoptosis in several neurons. Ca2+ permeable TRPM2 channel was gated by ADPribose (ADPR) and reactive oxygen species (ROS), although its activity was modulated in HYPX-exposed neurons by resveratrol (RSV). The aim of this study was to evaluate if a therapy of RSV can modulate the effect of HYPX in the TRPM2 expressing SH-SY5Y neuronal and HEK293 (no expression of TRPM2) cell lines. The SH-SY5Y and HEK293 cells were divided into four groups as control, RSV (50 mu M and 24 hours), and HYPX and RSV + HYPX. For induction of HYPX in the cells, CoCl2 (200 mu M and 24 hours) incubation was used. HYPX-induced intracellular Ca2+ responses to TRPM2 activation were increased in the SH-SY5Y cells but not in the HEK293 cells from coming H2O2 and ADPR. RSV treatment improved intracellular Ca2+ responses, mitochondrial function, suppressed the generation of cytokine (IL-1 beta and TNF-alpha), cytosolic and mitochondrial ROS in the SH-SY5Y cells. Intracellular free Zn2+, apoptosis, cell death, PARP-1, TRPM2 expression, caspase -3 and -9 levels are increased through activating TRPM2 in the SH-SY5Y cells exposed to the HYPX. However, the values were decreased in the cells by RSV and TRPM2 blockers (ACA and 2-APB). In SH-SY5Y neuronal cells exposed to HYPX conditions, the neuroprotective effects of RSV were shown to be exerted via modulation of oxidative stress, inflammation, apoptosis and death through modulation of TRPM2 channel. RSV could be used as an effective agent in the treatment of neurodegeneration exposure to HYPX.Öğe Selenium prevents interferon-gamma induced activation of TRPM2 channel and inhibits inflammation, mitochondrial oxidative stress, and apoptosis in microglia(Springer/Plenum Publishers, 2021) Akyuva, Yener; Naziroglu, Mustafa; Yildizhan, KenanMicroglia as the primary immune cells of brain act protective effects against injuries and infections in the central nervous system. Inflammation via excessive Ca(2+)influx and oxygen radical species (ROS) generation is a known factor in many neurodegenerative disorders. Importantly, the Ca(2+)permeable TRPM2 channel is activated by oxidative stress. Thus, TRPM2 could provide the excessive Ca(2+)influx in the microglia. Although TRPM2 expression level is high in inflammatory cells, the interplay between mouse microglia and TRPM2 channel during inflammation is not fully identified. Thus, it is important to understand the mechanisms and factors involved in order to enhance neuronal regeneration and repair. The data presented here indicate that TRPM2 channels were activated in microglia cells by interferon-gamma (IFN gamma). The IFN gamma treatment further increased apoptosis (early and late) and cytokine productions (TNF-alpha, IL-1 beta, and IL-6) which were due to increased lipid peroxidation and ROS generations as well as increased activations of caspase -3 (Casp-3) and - 9 (Casp-9). However, selenium treatment diminished activations of TRPM2, cytokine, Casp-3, and Casp-9, and levels of lipid peroxidation and mitochondrial ROS production in the microglia that were treated with IFN gamma. Moreover, addition of either PARP1 inhibitors (PJ34 or DPQ) or TRPM2 blockers (2-APB or ACA) potentiated the modulator effects of selenium. These results clearly suggest that IFN gamma leads to TRPM2 activation in microglia cells; whereas, selenium prevents IFN gamma-mediated TRPM2 activation and cytokine generation. Together the interplay between IFN gamma released from microglia cells is importance in brain inflammation and may affect oxidative cytotoxicity in the microglia.Öğe Silver nanoparticles potentiate antitumor and oxidant actions of cisplatin via the stimulation of TRPM2 channel in glioblastoma tumor cells(Elsevier Ireland Ltd, 2023) Akyuva, Yener; Nazirog, MustafaWe investigated the effects of silver nanoparticle (AgNP) and cisplatin (CiSP) exposure via the activation of TRPM2 cation channels in glioblastoma (DBTRG-05MG) cell line. The cells were divided into four groups as control, AgNPs (100 mu g/ml for 48 h), CiSP (25 mu M for 24 h), and CiSP + AgNPs. We found that the cytotoxic, oxidant and apoptotic actions of CiSP were further stimulated through the activation of TRPM2 (via ADP-ribose and H2O2) in the cells by the treatment of AgNPs. The actions were decreased in the cells by the treatments of TRPM2 antagonists (ACA and 2APB). The apoptotic actions of AgNPs were induced by the stimulation of propidium iodide positive DBTRG-05MG rate, caspase -3, caspase -8, and caspase -9 activations, although their oxidant actions were acted by the increase of mitochondrial membrane depolarization, lipid peroxidation, mitochondrial oxygen free radicals (ROS), and cytosolic ROS, but the decrease of total antioxidant status, glutathione, and glutathione peroxidase. The accumulation of cytosolic free Ca2+ and Zn2+ into mitochondria via the activation of TRPM2 current density and activity accelerated oxidant and apoptotic actions of AgNPs in the cells. We found that the combination of AgNPs and CiSP was synergistic via the stimulation of TRPM2 for treatment of DBTRG-05MG cells. The combination of AgNPs and CiSP showed a favorable action via the stimulation of TRPM2 in the treatment of glioblastoma tumor cells.
