Browsing by Author "Umur A.S."
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Item B cell immunoblastic lymphoma of central nervous system: Case report(Turkish Neurosurgical Society, 2003) Umur A.S.; Temiz C.; Selçuki M.; Mirzai H.; Okudur I.; Özkal B.; Işisaǧ A.Primary central nervous system lymphoma (PCNSL) is defined as the lymphoma effecting only spinal axis and cranium without systemic symptoms. PCNSL is very rare. Hystologic type of lymphoma that arising in the CNS is most commonly B cell lymphoma. In our study we reported a 47 years old female patient with B cell non-hodgkin's lymphoma of CNS with no evidence of lymphoma outside the CNS. There was no evidence of systemic acquired immundeficiency syndrome.Item Adult tethered cord syndrome mimicking lumbar disc disease(2008) Umur A.S.; Selcuki M.; Selcuki D.; Bedük A.; Doganay L.Object: This paper reports four tethered cord cases who initially applied with lumbar disk disease symptoms. Materials and methods: All of them were investigated by magnetic resonance imaging (MRI) and somatosensory evoked potential (SSPE). In two patients, MRI revealed thick and fatty filum terminale, while in remaining two, the filum terminale appeared as normal in thickness. SSEP revealed pathological conduction values in all, and it was the main indicator for surgical sectioning in patients especially with normal MRI investigations. All patients had benefit from the surgical sectioning of the fila terminalia with either thick and fatty or normal appearance. Conclusion: A particular patient with lumbar disc disease symptoms having normal MRI should also be investigated for tight filum terminale. If there is no pathological appearance in MRI investigation (both in regard to disc herniation and thick and fatty filum terminale), SSEP investigation should be done to check whether a conduction block or delay is present, indicating cord tethering. © Springer-Verlag 2007.Item Apoptosis seems to be the major process while surface and neural ectodermal layers detach during neurulation(2008) Selçuki M.; Vatansever S.; Umur A.S.; Temiz C.; Sayin M.Objective: 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. © Springer-Verlag 2007.Item Effect of sodium phenytoin concentration on neural tube development in the early stages of chicken embryo development(2009) Temiz C.; Temiz P.; Demirel A.; Sayin M.; Umur A.S.; Özer F.D.Animal 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. © 2008 Elsevier Ltd. All rights reserved.Item The effects of meloxicam on neural tube development in the early stage of chick embryos; [Meloksikamın erken dönem civciv embriyosunda nöral tüp geliflimine etkileri](Turkish Neurosurgical Society, 2010) Cetinkal A.; Colak A.; Topuz K.; Demircan M.N.; Simsek H.; Berber U.; Umur A.S.; Selcuki M.; Vatansever H.S.AIM: The aim of this study is to demonstrate the effect of meloxicam in early stage chick embryos on neural tube development. MATERIAL and METHODS: One hundred specific pathogen-free (SPF) chicken eggs were used to investigate the neurulation. SPF eggs were invastigated in four groups (n:25). All of the groups were incubated at 37.2 ± 0.1°C and 60 ± 5 % relative humidity for 30 hours, and an embryological development in the ninth stage as classified by Hamburger and Hamilton was obtained. In the end of the 30th hour, group A(control group) was administered 0.1 ml of saline (0.9% NaCl) in ovo and the other groups were administered meloxicam in increasing doses. At the end of 72 hours, all of the embryos were extracted from eggs and they underwent pathological examination with hematoxylin eosine and immunohistopathological examinations with CD138 and tubulin beta II. RESULTS: While the groups Aand B showed no neural tube defects, totally eight defective embryos were detected in the groups C and D (three in group C and five in group D. CONCLUSION: Our results suggested that meloxicam, a nonselective COX inhibitor, caused neural tube closure defects when injected at supratherapeutic doses. However, further studies with larger numbers of subjects are needed for its use in lower doses.Item Simultaneous folate intake may prevent advers effect of valproic acid on neurulating nervous system(2012) Umur A.S.; Selcuki M.; Bursali A.; Umur N.; Kara B.; Vatansever H.S.; Duransoy Y.K.Purpose: The aim of this study is to elucidate the preventive effect of folic acid (FA) on teratogenic effects of valporic acid (VA) in early stage chick embryos on neural tube development. Materials and methods: One hundred and fifty specific pathogen-free (SPF) chick eggs were used to investigate the neurulation in five groups. Group A was the control group. Group B was injected 0.02 ml of saline (0.9% NaCl) and was used for sham group. VA (0.72 mg) in 0.02 ml saline was injected in Group C, and 0.342 mcg of FA in 0.02 ml NaCl were administered to the embryos in Group D. VA (0.72 mg)+0.342 mcg of FA in 0.02 ml saline were administered simultaneously to the eggs in Group E. At the end of 72 h, all embryos were extracted from eggs and were fixed, and for histological analyses hematoxylin and eosine was used, for detection of apoptotic cells terminal deoxyribonucleotide transferase-mediated dUTP-X nick end labeling (TUNEL) was used and for distribution of P53, bcl-2 and caspase-3, caspase-6, caspase-8 and caspase-9 immunoperoxidase techniques were used. Results: While there were no neural tube defects in the embryos of groups A, B and D, eight embryos died in group C and there were 12 embryos with retarded embryological development. In contrast to that, no death was observed in group E, but only eight embryos were detected with maldevelopmental delay stage. Conclusion: These results suggested that VA may induce apoptotic mechanisms but not through the p53 pathway. In addition, FA effectively prevents the teratogenic influence of VA on chick embryo at neurulation stages by stopping cascade of apoptosis before caspase 3 expression. © 2012 Springer-Verlag.Item TGF-βs and SMADs activities at the site of failed neural tube in the human embryos(Turkish Neurosurgical Society, 2013) Barutcuoglu M.; Umur A.S.; Vatansever H.S.; Umur N.; Ozbilgin K.; Sayhan S.; Selcuki M.Aim: Transforming growth factor β (TGF-β) and Smads control intracellular signaling pathways in neurulation. Although previously reported similar experimental animal studies, the aim of this human study is to investigate the expression of TGF-β (1,2,3) and Smads (1,2,3,6,7) in aborted human fetuses with myeloschisis. Material and Methods: Twelve human fetuses with neural tube defect were obtained. They were stained with antibodies against TGF-β1, TGF-β2, TGF-β3, Smad (1,2,3), Smad 6 and Smad 7 using the indirect immunohistochemical technique. Results: We noted mild immune reactivity of TGF-β1 and TGF-β2 in the open neural plate, motor neurons and surrounding tissue. Strong immune reactivity of TGF-β3 was shown in only open neural plate and surrounding tissue. Immunoreactivity of all Smads noted negative except Smad7. ConclusIon: These results suggested at the site where the neural tube failed to close, TGF-β 1,2 and Smads 1,2,3,6 do not continue their activity and decrease with internal timing of embryonic development. Additionally ectodermal layers are considered by embryo as "not closed wound" and TGF-β3 activity may be an effort to repair the failed closure.Item Evaluation of the effects of mobile phones on the neural tube development of chick embryos(Turkish Neurosurgical Society, 2013) Umur A.S.; Yaldiz C.; Bursali A.; Umur N.; Kara B.; Barutcuoglu M.; Vatansever S.; Selcuki D.; Selcuki M.Aim: The objective of this study is to examine the effects of radiation of mobile phones on developing neural tissue of chick embryos. Material and Methods: There were 4 study groups. All Groups were placed in equal distance, from the mobile phones. Serial sections were taken from each Group to study the neural tube segments. Results: The TUNEL results were statistically significant (p<0.001) at 30 and 48 hours in the third Group. We found low Bcl-2 levels partly in Group 4 and increased activity in Group 3. Caspase-3 was negative in the 48 and 72 hours in the Control Group, had moderate activity in the third Group 3, weak activity in the 48 hour, and was negative in the 72 hour in other groups. Caspase-9 immunoreactivity was weak in Group 1, 2 and 3 at 30 hours and was negative in Group 1 and 4 at 48 and 72 hours. Caspase-9 activity in the third Group was weak in all three stages. Conclusion: Electromagnetic radiation emitted by mobile phones caused developmental delay in chick embryos in early period. This finding suggests that the use of mobile phones by pregnant women may pose risks.Item Preoperative and postoperative evaluation of somatosensorial evoked potentials of upper extremities in cervical intervertebral disc herniation(Turkish Neurosurgical Society, 2013) Umur A.S.; Selcuki M.; Selcuki D.; Temiz C.; Akbasak A.This study aims to determine the dysfunction caused by existing pathological condition in structures involved in the transfer of sensory functions of the neural system in cervical disc herniation, and to establish whether or not the level and degree of this anatomical damage can be anticipated by SEP (Somatosensorial Evoked Potentials). We compared the obtained SEP values for statistical significance using the Friedman Variation Analysis. In parameters with statistical significance, the Wilcoxon Signed Rank test was used to identify when significant improvements occurred. The study found that the statistical data of the latency of the N14 wave originating from the dorsal column nuclei of the medulla spinalis and dorsal column gray matter improved (p<0.05) in the postoperative period compared with the preoperative values. Using the Wilcoxon Signed Rank test, we studied postoperative months separately in regard to the difference in the latency of the N14 wave, and found the statistically significant improvement to be marked particularly in months 3 and 6 postoperatively (p<0.05). In conclusion, we suggest that SEP is a useful tool to check the functional condition of the dorsal spinal column. The benefit of the SEP utilization is the ability to determine the severity of the pathological condition preoperatively and follow the patient's functional postoperative improvement.Item Congenital dermal sinus tract of the spine: Experience of 16 patients(SAGE Publications Inc., 2014) Mete M.; Umur A.S.; Duransoy Y.K.; Barutçuoʇlu M.; Umur N.; Gurgen S.G.; Selçuki M.Congenital dermal sinus tract is a rare entity which lined by epithelial cells and can end anywhere between subcutaneous planes to thecal sac. These tracts may be accompanied with other pathologies such as lipomyelomeningocele, myelomeningocele, split cord malformation, tethered cord, filum abnormality and inclusion tumors and treatment includes resection of tract with intradural exploration. The authors review their experience with 16 cases. Clinical, radiological appearance and treatment of these lesions discussed with literature review. © The Author(s) 2014.Item Unusual presentation of congenital dermal sinus: Tethered cord with paramedian cutaneous ostia(Lippincott Williams and Wilkins, 2015) Mete M.; Simsek T.; Umur A.S.; Selçuki M.; Umur N.; Gurgen S.G.Congenital dermal sinus tract is a rare dysraphism with an incidence of 1/2500-3000 ratio. The sinus ostium located in the midline of the posterior of the body from the occiput to the lumbosacral region. Paramedian congenital dermal sinus tract with paramedian ostium are rare. Here, we describe a 2-year-old boy who presented with paramedian pigmented lesion with an ostium on the left lumbosacral region. During surgery we noted that sinus tract attached to thick lipomatous filum terminale. © 2013 Wolters Kluwer Health, Inc.Item Tethered cord syndrome in adults: Experience of 56 patients(Turkish Neurosurgical Society, 2015) Selcuki M.; Mete M.; Barutcuoglu M.; Duransoy Y.K.; Umur A.S.; Selcuki D.Aim: The aim of this study was to describe the results of surgery performed in a group of adult patients with tethered cord syndrome with their outcomes. Material and Methods: This retrospective study included 56 patients. There were 38 females and 18 males. All patients were older than 18 years. Results: The mean age at referral was 36 years and 1 month. The mean follow-up period was 10 months 27 days. 95% of all patients with back and leg pains improved and 5% remained the same. Three patients with motor deficits remained the same in the postoperative period. Of the 16 patients with urological complaints, 10 improved, 5 unchanged and 1 patient died in the postoperative first day due to pulmonary embolism. Conclusion: The syndrome of tethered cord may be a situation to be treated even in the elderly in case of normal level conus medullaris and filum terminale with a normal appearance as well as a low-lying conus and thick filum. To prevent overlooking the diagnosis of tethered cord and/or unnecessary spinal surgeries, the tethered cord syndrome should be remembered in the differential diagnosis list in the presence of back and leg pains, neurological deficits or urological complaints.Item Double split cord malformations in a child: Types I and II at 2 different levels in the same route: Report of a rare case(Lippincott Williams and Wilkins, 2015) Barutçuoʇlu M.; Umur A.S.; Özdemir S.; Mete M.; Selçuki M.Spinal split cord malformations (SSCMs) are thought to be originated from an error that causes splitting of the notochord during gastrulation period, in which the formation of an accessory neurenteric canal between the yolk sac and amnion cavity takes place. Herein, we reported a 1-month-old boy who had both type II SSCM with meningocele at Th2-4 level and type I SSCM at Th10-12 level. Between those 2 malformations there was a normally developed spinal cord. Lesions were surgically corrected with good cosmetic and neurological outcome. There have been divergent suggestions on these pathologies. Although the multisite closure model of the neural tube may be used for explanation of these multiple neural tube defects, this theory alone cannot explain the nature and mechanism of development of such developmental defects of the neural tube. The aim of this study is to understand the embryological changes that cause the formation of a composite split spinal cord malformation. The idea of temporally different unexpected events that may cause developmental defects at different levels while other segments continue to neurulate normally seems appropriate to explain the multiple midline closure defects. Copyright © 2014 Wolters Kluwer Health, Inc. All rights reserved.Item Primary Intraorbital Hydatid Cyst in a Child(Lippincott Williams and Wilkins, 2015) Mete M.; Umur A.S.; Duransoy Y.K.; Selçuki M.Intraorbital hydatid disease is quite rare and its incidence has been reported to range from 0.3% to 1.0% among patients with Echinococcosis. The authors report a 4-year-old boy with primary intraorbital hydatid cyst who had presented with proptosis of the left eye. Because of high risk for cyst rupturing, the cyst was aspirated-injected simultaneously and reaspirated and then removed totally. © 2014 Wolters Kluwer Health, Inc. All rights reserved.Item Use of Chicken Embryos as an Angiogenesis Model for Central Nervous System Malignant Tumor Research(Turkish Neurosurgical Society, 2023) Umur N.; Gurgenv S.G.; Sarsmaz H.Y.; Umur A.S.AIM: To demonstrate the usability of chicken chorioallantoic membrane (CAM) as an angiogenesis model for the development and treatment of malignant tumors of the central nervous system. MATERIAL and METHODS: A fresh tumor tissue piece taken from Glioblastoma patients, a malignant tumor of the central nervous system, was transferred to the CAM of chicken embryos and left to incubate in the incubator and their development was monitored. After examining the results of the study macroscopically, CAM tissue samples were evaluated both histochemically and immunohistochemically in terms of angiogenic factors VEGF (Vascular Endothelial Growth Factor), bFGF (basic Fibroblast Growth Factor) and PDGF (Platelet Derived Growth Factor). RESULTS: According to histochemical findings obtained from our study when compared with control embryos, blood vessels, fibroblast count and inflammatory infiltration were observed more in the tumor transplanted groups, especially in the tumordeveloping CAM region. There was also intense pleomorphism and marked hypercellularity in the cells. In our immunohistochemical findings, it was determined that bFGF, PDGF, VEGF staining intensities were higher in tumor transplanted groups compared to control groups, and this elevation was more pronounced in the tumor-developing region. CONCLUSION: As a result, it has been shown that the chicken embryo CAM model may be a suitable in vivo model for cancer angiogenesis studies. The protocol we created in this study will be a source for projects related to the use of therapeutic agents in cancer angiogenesis © 2023, Turkish Neurosurgery.All Rights Reserved.