Person: ŞEHİRLİ, ÜMİT SÜLEYMAN
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ŞEHİRLİ
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ÜMİT SÜLEYMAN
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Publication Open Access Cerebellar connections to the rostral reticular nucleus of the thalamus in the rat(WILEY, 2002-12) ONAT, FİLİZ; Cavdar, S; Onat, FYL; Yananli, HR; Sehirli, US; Tulay, C; Saka, E; Gurdal, EWe studied the cerebellar connections to the reticular nucleus thalamus (RNT) by means of retrograde axonal transport of horseradish peroxidase (HRP) in the rat. Specific HRP pressure injections to the rostral RNT(1.6-1.8 mm caudal to bregma) resulted in retrograde labelling of neurones in the cerebellar nuclei. The rostral RNT showed specific topographical organization of its cerebellar connections. Microinjections into the rostral RNT, 1.6 mm caudal to bregma, produced numerous HRP-labelled neurones within the anterior interposed (emboliform nucleus) and scarce HRP-labelled neurones within the lateral (dentate nucleus) cerebellar nuclei, whereas injections into the rostral RNT, 1.8 mm caudal to bregma, produced numerous HRP-labelled neurones within the posterior interposed (globose nucleus) and scarce lightly HRP-labelled neurones within the lateral (dentate nucleus) cerebellar nuclei. Cerebellar connections with the rostral RNT were exclusively ipsilateral to the injection site. No HRP-labelled cells were detected in the medial (fastigial nucleus) cerebellar nucleus. The cerebellar connections reach the RNT via the superior cerebellar peduncle. By contrast, HRP injections into the anterior, posterior interposed and lateral cerebellar nuclei produced no labelled cells within the RNT. This study demonstrates the existence of direct cerebello-RNT but not RNT-cerebellar connections. The presence of the cerebello-RNT connections introduces a new route through which the cerebellum may influence RNT and thus cerebral cortical activity.Publication Metadata only Morphometric characteristics of caudal cranial nerves at petroclival region in fetuses(SPRINGER, 2016) ÖZKAN, MAZHAR; Ozdogmus, Omer; Saban, Enis; Ozkan, Mazhar; Yildiz, Sercan Dogukan; Verimli, Ural; Cakmak, Ozgur; Arifoglu, Yasin; Sehirli, UmitMorphometric measurements of cranial nerves in posterior cranial fossa of fetus cadavers were carried out in an attempt to identify any asymmetry in their openings into the cranium. Twenty-two fetus cadavers (8 females, 14 males) with gestational age ranging between 22 and 38 weeks (mean 30 weeks) were included in this study. The calvaria were removed, the brains were lifted, and the cranial nerves were identified. The distance of each cranial nerve opening to midline and the distances between different cranial nerve openings were measured on the left and right side and compared. The mean clivus length and width were 21.2 +/- A 4.4 and 13.2 +/- A 1.5 mm, respectively. The distance of the twelfth cranial nerve opening from midline was shorter on the right side when compared with the left side (6.6 +/- A 1.1 versus 7.1 +/- A 0.8 mm, p = 0.038). Openings of other cranial nerves did not show such asymmetry with regard to their distance from midline, and the distances between different cranial nerves were similar on the left and right side. Cranial nerves at petroclival region seem to show minimal asymmetry in fetuses.Publication Open Access The effects of melatonin on the striatum(MARMARA UNIV, FAC MEDICINE, 2021-10-31) BORACI, HATİCE; Gergin, Sinem; Kirazli, Ozlem; Boraci, Hatice; Yildiz, Sercan Dogukan; Sehirli, Umit SuleymanObjective: Some of the neurological diseases cause morphologic changes in the striatal neurons. Medial forebrain bundle (MFB) lesion is a commonly used method to produce a Parkinsonian model rat. Melatonin is a hormone which exerts a neuroprotective effect on the neurons. The aim of this study is to investigate the effect of melatonin on the dendritic morphology of striatal medium spiny neurons (MSNs) in rats with MFB lesion. Materials and Methods: Twelve male Wistar albino rats were given saline injections into the MFB and divided into sedentary and treatment groups. The treatment group was administered a 10 mg/kg dose of melatonin intraperitoneally for 30 days. The lesion was confirmed histologically by Nissl staining. Golgi staining technique was applied to observe neuronal morphology. Neuronal structures were analysed from three-dimensional images by Neurolucida (MBF Bioscience) software. Results: The MFB lesion caused a reduction in the total dendritic length and in the number of dendritic endings. The melatonin enhanced the number of dendritic endings compared to the sedentary group. The melatonin led to an increase in the total spine density, spine densities of thin and mushroom types. Conclusion: Melatonin improved the dendritic degeneration due to MFB lesion.Publication Metadata only Morphologic Characteristics of Meniscofemoral Ligaments(ORTADOGU AD PRES & PUBL CO, 2011) ŞEHİRLİ, ÜMİT SÜLEYMAN; Sozmen, Aycan Guclu; Yalin, Aymelek; Uzun, Ibrahim; Sehirli, Umit SuleymanObjective: The aim of this study was to describe the presence, lengths, widths, attachment sites, course of the fibers, histological properties and the sizes of the attachment sites of the meniscofemoral ligaments to the lateral meniscus. Material and Methods: Forty fresh frozen knees obtained from 22 human cadavers were examined. The knee was dissected by posterior approach and the anterior and posterior meniscofemoral and posterior cruciate ligaments were measured after exposing them. The sections of ligaments were stained with the Mason trichrome stain and under light microscope. Results: At least one of the meniscofemoral ligaments was present in 37 (92.5%) cases. Twenty (50%) were anterior meniscofemoral ligaments and 24(60%) were posterior. In seven cases (17.5%) both anterior and posterior meniscofemoral ligaments were present. The oblique fibers of the posterior cruciate ligament were observed in 11 (27.5%) cases. A separating membrane between the meniscofemoral ligaments and the posterior cruciate ligament was observed. The mean lengths of the posterior and anterior meniscofemoral ligaments were 23.82 +/- 1.51 mm and 21.55 +/- 0.97 mm, respectively. The mean widths of the anterior and posterior meniscofemoral ligaments were 3.43 +/- 0.57 mm and 4.09 +/- 0.77 mm, respectively. The mean lengths of the attachment sites of posterior and anterior meniscofemoral ligaments to lateral meniscus were 11.30 +/- 1.85 mm and 6.19 +/- 1.23 mm respectively and the mean widths were 3.39 +/- 0.92 mm and 4.88 +/- 0.96 mm, respectively. Conclusion: Details concerning the dimensions and histological properties of the meniscofemoral ligaments, their relation to the posterior cruciate ligament and lateral meniscus will contribute to a clear understanding of the biomechanics of the knee as well as the radiologic diagnosis and the treatment of knee problems.Publication Metadata only Wistar ve genetik absans epilepsili (GAERS) sıçanlarda dendrit morfolojisinin incelenmesi(2021-11-21) YAZI, SEVDENUR; ŞEHİRLİ, ÜMİT SÜLEYMAN; GÜLHAN, REZZAN; KİRAZLI, ÖZLEM; Yazı S., Şehirli Ü. S., Gülhan R., Onat F., Kirazlı Ö.Publication Metadata only Toraks anatomisi(Akademisyen, 2018-01-01) VERİMLİ, URAL; ŞEHİRLİ, ÜMİT SÜLEYMAN; ŞEHİRLİ Ü. S., VERİMLİ U.; Balcı, Akın Eraslan; Yüksel, MustafaPublication Metadata only Attitudes of Turkish anatomists toward cadaver donation(WILEY-LISS, 2004) SARIKAYA, ÖZLEM; Sehirli, US; Saka, E; Sarikaya, OThere is an insufficient number of cadavers in anatomy education in Turkey. This is because of decreased number of unclaimed bodies and very few cadaver donations. Increasing the number of cadaver donation is one of the probable solutions. Although anatomists encourage people to donate bodies, the attitudes of anatomists toward donating their own bodies for dissection is not well known. In this study, the attitudes of Turkish anatomists toward cadaver donation were evaluated. The questionnaires were sent to the anatomists in Turkey by mail and E-mail. Eighty-three anatomists replied to the questionnaire. The main solutions proposed for cadaver insufficiency included increasing the supply of unclaimed bodies (77.1%) and increasing body donation (78.3%). Further, 51.8% of the respondents thought that increasing body donation was a long-term solution. The general belief (83.1%) was that a campaign would help to increase body donation and 47% of respondents were willing to participate in such a campaign. Of the 83 anatomists, 20.5% of the respondents donated their organs and 49.4% were planning to donate them. Further, 15.7% were planning to donate their bodies; however, 63.9% did not consider donating. The main reasons of the respondents to object the donation were: to be dissected by a colleague (75.7%), the unacceptability of donation by family (26.5%), psychological reasons (43.4%), the anxiety of disrespectful behavior to cadavers (26.5%), and religious beliefs (3.6%). Although the majority of the respondents objected to donating their bodies due to psychological reasons, body donation was proposed as the main solution of cadaver insufficiency. (C) 2004 Wiley-Liss, Inc.Publication Metadata only The diameters of common carotid artery and its branches in newborns(SPRINGER FRANCE, 2005) ŞEHİRLİ, ÜMİT SÜLEYMAN; Sehirli, US; Yalin, A; Tulay, CM; Cakmak, YO; Gurdal, EThe common carotid artery (CCA) bifurcation is of clinical importance due to its vascular access site for intravascular intervention. Additionally, it is also one of the most common sites of atherosclerotic plaque formation. There are numerous studies on the diameters of CCA, internal carotid artery (ICA), and external carotid artery (ECA) in adults, but few studies on newborns. Cadaver and angiographic studies have shown dimensional variations in the carotid arteries within/between individuals and also between different sexes. It is well known that the initial lesions of atherosclerosis begin very early in fetal life. Therefore, it is important to know the anatomical details of the CCA and its branches. In the present study, the neck regions of 20 (11 males and 9 females) fixed newborn cadavers were dissected. The CCAs were cut below the bulb of the carotid bifurcation further; ICA and ECA were cut above the bulb of the carotid bifurcation. The internal diameters of the CCA, ICA, and ECA were measured using a light microscopy. ECA/CCA, ICA/CCA, ICA/ECA ratios, and outflow to inflow area ratio were calculated. The mean outflow to inflow area ratio was 1.14 +/- 0.28. Our results highly correlated with the defined optimal ratio (1.15). The ECA/CCA, ICA/CCA, and ICA/ECA ratios were 0.78 +/- 0.12, 0.71 +/- 0.13, and 0.93 +/- 0.16, respectively. There were no statistically significant differences between male and female and also between right and left sides. These findings are of importance in understanding the anatomy of carotid artery during newborn period.Publication Metadata only Depolarisation and suppression of burst firing activity in the mouse subthalamic nucleus by dopamine D1/D5 receptor activation of a cyclic-nucleotide gated non-specific cation conductance(PERGAMON-ELSEVIER SCIENCE LTD, 2008) ŞEHİRLİ, ÜMİT SÜLEYMAN; Loucif, Alexandre J. C.; Woodhall, Gavin L.; Sehirli, Umit S.; Stanford, Ian M.Neuronal burst firing in the subthalamic nucleus (STN) is one of the hallmarks of dopamine depletion in Parkinson's disease. Here, we have determined the postsynaptic effects of dopamine in the STN and the functional consequences of dopamine receptor modulation on burst firing in vitro. STN cells displayed regular spiking activity at a rate of 7.9 +/- 0.5 Hz. Application of dopamine (30 mu M) induced membrane depolarisations accompanied by an increase in firing rate of mean 12.0 +/- 0.6 Hz in all 69 cells. The dopamine effect was mimicked by the dopamine D1/D5 receptor agonist SKF38393 (10 mu M, 17 cells) and the dopamine D2-like receptor agonist quinpirole (10 mu M, 35 cells), partly reduced by D1/D5 antagonist SCH23390 (2 mu M, seven cells), but unaffected by the D2 antagonists sulpiride (10 mu M, seven cells) or eticlopride (10 mu M, six cells). Using voltage ramps, dopamine induced an inward current of 69 +/- 9.4 pA at a holding potential of -60 mV (n = 17). This current was accompanied by an increase in input conductance of 1.55 +/- 0.35 nS which reversed at -30.6 +/- 2.3 mV, an effect mimicked by SKF38393 (10 AM, nine cells). Similar responses were observed when measuring instantaneous current evoked by voltage steps and in the presence of the I-h blocker, ZD7288, indicating effects independent of I-h. The increase in conductance was blocked by SCH23390 (2 mu M, n = 4), mimicked by the activator of adenylyl cyclase forskolin (10 mu M, n = 7) and blocked by H-89, an inhibitor of cyclic AMP dependent protein kinase A (10 PM, n = 6). These results indicate that the dopamine depolarisation is in part mediated by D1/D5 receptor mediated activation of a cyclic-nucleotide gated (CNG) non-specific cation conductance. This conductance contributes to the membrane depolarisation that changes STN neuronal bursting to more regular activity by significantly increasing burst duration and number of spikes per burst. (c) 2008 Elsevier Ltd. All rights reserved.Publication Metadata only Evaluation of dendrite morphology in wistar and genetic absence epileptic (GAERS) rats(2022-07-09) ŞEHİRLİ, ÜMİT SÜLEYMAN; KİRAZLI, ÖZLEM; GÜLHAN, REZZAN; YAZI S., ŞEHİRLİ Ü. S., GÜLHAN R., ONAT F., KİRAZLI Ö.Aims The aim of the study is to examine the morphological features of dendrites and dendritic spines of pyramidal neurons in somatosensory cortex and hippocampus of Wistar and GAERS (Genetic Absence Epilepsy Rat from Strasbourg) rats. Methods GAERS (n=5) and Wistar (n=5) rats were sacrificed by transcardial perfusion method. Brain tissues were stained using the FD Rapid GolgiStain Kit. Coronal sections of 200 µm thickness were obtained with cryostat. Pyramidal neurons in deep layers of the somatosensory cortex and CA1 region of the hippocampus were examined using light microscope and Neurolucida 360 software. Branching and length of apical dendrite and basal dendrites, and types and densities of dendritic spines were analyzed. Results Statistically the total number of dendrite nodes (p=0.0053, p=0,0047), the total number of dendrite segments (dendritic arborization) (p=0.0036, p=0,0036), the total number of dendrite terminations (p=0.0033, p=0,0029), the total dendrite length (µm) (p=0.0002, p=0,0007) and the dendritic spine density (1/µm) (p=0.0168, p=0,0120) of the somatosensory cortex and the hippocampus were significantly higher in GAERS rats, respectively. When dendritic spine types were evaluated separately, stubby type dendritic spines in the hippocampus were found to be significantly higher in GAERS rats compared to Wistar rats (p=0.0204). Conclusions It was concluded that intense synaptic activation seen in postsynaptic cells in the somatosensory cortex and hippocampus in GAERS causes changes in the dendrite morphology of pyramidal neurons. This study was supported by Marmara University Scientifical Research Projects Commission (TYL-2021-10244).
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