Yazar "Özkan, Mazhar" seçeneğine göre listele
Listeleniyor 1 - 13 / 13
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe A cadaveric study: the relationship between sternum and internal thoracic artery(Japan International Cultural Exchange Foundation, 2021) Aydın, D.D.; Özkan, Mazhar; Öztürk, A.; Cıgalı, B.S.Introduction: Internal thoracic artery is an artery which frequently used in coronary bypass operations. Morphological features such as the location, length, and separation point of the branches are important crucialy. Materials and Methods:. The measurements were made in 11 thorax dissections and morphological data of ITA were obtained and photographed At each sternebra level, a midpoint was determined. The line created by combining these points was called the paramedian line. The distance between the artery and this line in the 2-5 intercostal space was measured. The distance of the artery and the lateral margin of sternum from the was measured at 2-5 intercostal spaces. The length of artery and the branch-ing point was recorded also. Results: The length of the right internal thoracic artery (between 2-5. intercostal space) is 117.07 mm. The left one is 118.63 mm. Maximum length for the right and left ITA 135 mm and 135.5 mm, respectively. The distance between paramedian line and bifurcatio of right ITA 31.06 mm and left ITA 32.32 mm. Maximum distance between paramedian line and bifurcatio of right ITA is 42.45 mm and the left one is 53.8 mm. Discussion: ITA is commonly used artery for coronary revascularization. When left anterior descending artery is anastomo-sed with ITA, survival rate has been found 10% for ten years. However, there are some disadvantages. As a result of pleurotomy, it can/could be seen several complications: parenchymal trauma, pleural effusion, atelectasis and pulmonary complication. Its is crucial to preservation of pleural integrity during dissection to reach ITA. Thus, it is supplied respiratory mechanisms and mini-mized lung injury. Conclusion: Internal thoracic artery has a great importance in coronary revascularization. When the risk of complications in coronary bypass operations is considered, the length of this artery and its distance with sternum should be clearly deter-mined. It is vital in the postoperative period and prolonging the life span. © 2021 Japan University of Health Sciences & Japan International Cultural Exchange Foundation.Öğe Bibliometric Analysis of Multiple Sclerosis Studies in Pharmacology Journals(2024) Özkan, Mazhar; Yüksel, Tuğba Nurcan; Tozoğlu, FatihMultiple sclerosis (MS) is a prevalent neurological disease with a global impact on patients' lives. Our study aimed to conduct a bibliometric analysis of research published in the field of pharmacology over the past decade. We retrieved original articles on MS from pharmacology journals in the last ten years through the Scopus database. The collected data underwent analysis using VOSViewer software, examining relationships between studies based on parameters such as citation, authorship, and organizations. In our country-based analysis, the United States emerged with the highest document count, totaling 350, followed by Germany with 210 documents. Claudio Viegas holds the top position with four publications in the last decade. The most prolific organization identified was associated with the Biogen-Cambridge-MA-United States group. However, Chulalongkorn University in Bangkok, Thailand, specifically the Department of Psychiatry, received the most citations. The most cited document was \"Therapeutic Advances in Neurological Disorders,\" while the study with the highest citations was Ferreria-Vieira et al.'s (2016) work published in Current Neuropharmacology. Research efforts on MS treatment are evidently growing, with diverse research groups contributing worldwide. We anticipate that our study will provide valuable guidance to researchers in the field by shedding light on significant research and their interconnections in recent years.Öğe Bilateral variations of the great saphenous vein(Marmara University, 2021) Zeybek, Ali; Özkan, Mazhar; Alpay, MeltemThe great saphenous vein is the longest in the human body and has been one of the most preferred autologous tissue in bypass surgery. It is affected by the life conditions causing pathological dilatations called varices. We observed bilaterally duplicated great saphenous vein in both lower limbs of an elderly male human cadaver during our routine dissection for undergraduate anatomy education. After a detailed inspection of the veins at both sides, we measured and illustrated the variant branches. In this case report, we presented bilaterally duplicated great saphenous veins, accompanied by an accessory saphenous vein. To the best of our knowledge, there are no such variations reported in the literature so far. We think that recognizing this and such variations before surgery will increase success. © 2021 Marmara University Press, All Rights Reserved.Öğe Comparing astrocytic gap junction of genetic absence epileptic rats with control rats: an experimental study(Springer Science and Business Media Deutschland GmbH, 2021) Çavdar, Safiye; Köse, Büşra; Sur-Erdem, İlknur; Özkan, MazharThe synchronization of astrocytes via gap junctions (GJ) is a crucial mechanism in epileptic conditions, contributing to the synchronization of the neuronal networks. Little is known about the endogenous response of GJ in genetic absence epileptic animal models. We evaluated and quantified astrocyte GJ protein connexin (Cx) 30 and 43 in the somatosensory cortex (SSCx), ventrobasal (VB), centromedian (CM), lateral geniculate (LGN) and thalamic reticular (TRN) nuclei of thalamus of genetic absence epilepsy rats from Strasbourg (GAERS), Wistar albino glaxo rats from Rijswijk (WAG/Rij) and control Wistar animals using immunohistochemistry and Western Blot. The Cx30 and Cx43 immunopositive astrocytes per unit area were quantified for each region of the three animal strains. Furthermore, Cx30 and Cx43 Western Blot was applied to the tissue samples from the same regions of the three strain. The number of Cx30 immunopositive astrocytes showed significant increase in both GAERS and WAG/Rij compared to control Wistar in all brain regions studied except LGN of WAG/Rij animals. Furthermore, Cx43 in both GAERS and WAG/Rij showed significant increase in SSCx, VB and TRN. The protein expression was increased in both Cx30 and Cx43 in the two epileptic strains compared to control Wistar animals. The significant increase in the astrocytic GJ proteins Cx30 and Cx43 and the differences in the co-expression of Cx30 and Cx43 in the genetically absence epileptic strains compared to control Wistar animals may suggest that astrocytic Cx’s may be involved in the mechanism of absence epilepsy. Increased number of astrocytic Cx’s in GAERS and WAG/Rij may represent a compensatory response of the thalamocortical circuitry to the absence seizures or may be related to the production and/or development of absence seizures. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.Öğe Comparison of astrocytes and gap junction proteins in the white matter of genetic absence epileptic and control rats: an experimental study(Taylor and Francis Ltd., 2022) Çavdar, Safiye; Köse, Büşra; Özkan, Mazhar; Sur Erdem, İlknurObjectives: The role of white matter astrocytes in absence epilepsy is unknown. The present study aims to quantify astrocytic markers glial fibrillary acidic protein (GFAP), gap junction’s proteins connexin 30 (Cx30) and connexin 43 (Cx43) in the corpus callosum (CC) of genetic absence epileptic rats from Strasbourg (GAERS), Wistar albino glaxo rats from Rijswijk (WAG/Rij)and compare the results with control animals. Methods: -The density of GFAP, Cx30 and Cx43 positive astrocytes in per unite area were quantified in the CC of GAERS, WAG/Rij and control animals using immunohistochemistry and real-time quantitative polymerase chain reaction (RT-qPCR). The quantifications were made from three regions of CC; below the primary somatosensory (S1BF), below the motor (M1) and below the retrosplenial (RSG) cortices. Results: oThe number GFAP, Cx30 and Cx43 immunopositive astrocytes showed heterogeneous distribution within the CC. The GFAP immunopositive astrocytes was significantly high in the S1BF region of the three strains. The immunopositive GFAP and Cx43 showed significant decrease in the S1BF and M1 regions in GAERS and WAG/Rij compared to control animals, however, an increase in the immunopositive Cx30 was observed in the same regions in both GAERS and WAG/Rij compared to control Wistar animals but the increase was significant for GAERS but not for WAG/Rij. The RT-qPCR analysis was corroborated by GFAP immunohistochemistry results. Conclusion: The different expression pattern of the two Cx’s in the CC of the epileptic strains compared to control animals may indicate a compensatory response or maybe the cause of generalization of absence seizures. © 2022 Informa UK Limited, trading as Taylor & Francis Group.Öğe Comparison of the Morphologic and Mechanical Features of Human Cranial Dura and Other Graft Materials Used for Duraplasty(Elsevier Inc., 2022) Çavdar, Safiye; Sürücü, Selçuk; Özkan, Mazhar; Köse, Büşra; Malik, Anjum Naeem; Aydoğmuş, Evren; Tanış, ÖzgülObjective: This study aimed to compare the thickness and mechanical properties of the frontal; parietal; temporal; occipital human dura; autogenous grafts (facia lata, temporal fascia, galea aponeurotica); and artificial dura. Methods: Sagittal and transverse dura samples were obtained from standard regions of the cranial dura from 30 autopsies for histologic and mechanical property measurements. Identical measurements were made for the autogenous grafts artificial dura, and the results were statistically analyzed. Results: The thickness of the temporal (0.35 ± 0.11 mm), parietal (0.44 ± 0.13 mm), frontal (0.38 ± 0.12 mm), and occipital (0.46 ± 0.18 mm) dura showed regional variations. The parietal and occipital dura were significantly thicker than the temporal dura. The occipital dura was considerably thicker than the frontal dura. The frontal and temporal dura of males were significantly thicker than females. The sagittal maximum tensile force measurements were significantly greater than transverse, for the frontal, temporal, and occipital dura. The stiffness measurements in sagittal direction were greater than the measurements in transverse direction for the frontal dura. The mechanical properties and thickness of the autogenous and artificial dura were not similar to the human dura. Conclusions: The thickness and mechanical properties of the regional cranial dura should be taken into consideration for a better cure and fewer complications. The mechanical properties of sagittal and transverse dura should be kept in mind for the preference of dura material. The present study's data can pave the way to produce artificial regional dura by mimicking the thickness and mechanical properties of the human dura. © 2021Öğe Correction to: Comparing astrocytic gap junction of genetic absence epileptic rats with control rats: an experimental study (Brain Structure and Function, (2021), 226, 7, (2113-2123), 10.1007/s00429-021-02310-y)(Springer Science and Business Media Deutschland GmbH, 2022) Çavdar, Safiye; Köse, Büşra; Sur-Erdem, İlknur; Özkan, MazharIn Fig. 1 of this article, the preparations of the image panels the GAERS Cx30 for LGN, CM and TRN was inadvertently mixed with WAG/Rij Cx30. The Fig. 1 should have appeared as shown below. © 2022, Springer-Verlag GmbH Germany, part of Springer Nature.Öğe Discussion on the Artificial Intelligence (AI) Tools Usage in the Scientific World(2023) Özkan, Mazhar; Sasani, Hadi[Abstract Not Available]Öğe Does astrocyte gap junction protein expression differ during development in absence epileptic rats?(John Wiley and Sons Inc, 2022) Köse, Büşra; Özkan, Mazhar; Sur-Erdem, İlknur; Çavdar, SafiyeIntercellular communication via gap junctions (GJs) has a wide variety of complex and essential functions in the CNS. In the present developmental study, we aimed to quantify the number of astrocytic GJs protein connexin 30 (Cx30) of genetic model of absence epilepsy rats from Strasbourg (GAERS) at postnatal P10, P30, and P60 days in the epileptic focal areas involved in the cortico-thalamic circuit. We compared the results with Wistar rats using immunohistochemistry and western blotting. The number of Cx30 immunopositive astrocytes per unit area were quantified for the somatosensory cortex (SSCx), ventrobasal (VB), and lateral geniculate (LGN) thalamic nuclei of the two strains and Cx30 western blot was applied to the tissue samples from the same regions. Both immunohistochemical and western blot results revealed the presence of Cx30 in all regions studied at P10 in both Wistar and GAERS animals. The SSCx, VB, and LGN of Wistar animals showed progressive increase in the number of Cx30 immunopositive labeled astrocytes from P10 to P30 and reached a peak at P30; then a significant decline was observed from P30 to P60 for the SSCx and VB. However, in GAERS Cx30 immunopositive labeled astrocytes showed a progressive increase from P10 to P60 for all brain regions studied. The immunohistochemical data highly corresponded with western blotting results. We conclude that the developmental disproportional expression of Cx30 in the epileptic focal areas in GAERS may be related to the onset of absence seizures or may be related to the neurogenesis of absence epilepsy. © 2022 Wiley Periodicals LLCÖğe Non-motor connections of the pedunculopontine nucleus of the rat and human brain(Elsevier Ireland Ltd, 2022) Özkan, Mazhar; Köse, Büşra; Algın, Oktay; Oğuz, Sinem; Erden, Mert Emre; Çavdar, SafiyeIntroduction: The connections of the pedunculopontine nucleus (PPN) with motor areas of the central nervous system (CNS) are well described in the literature, in contrast relations with non-motor areas are lacking. Thus, the aim of the present study is to define the non-motor connections of the PPN in rats using the fluoro-gold (FG) tracer and compare the presence of these connections in healthy human adults using diffusion tensor tractography (DTI). Materials and Methods: We injected FG into the PPN of 12 rats. The non-motor connections of the PPN with cortical, subcortical, and brainstem structures were documented. The non-motor connections of the rats were compared with the DTI obtained from 35 healthy adults. Results: The results of the tract-tracing study in the rat showed that the PPN was connected to non-motor cortical (cingulate, somatosensory, visual, auditory, medial frontal cortices), subcortical (amygdala, hypothalamus, thalamus, habenular, and bed nucleus of stria terminalis), and brainstem (medullary reticular, trigeminal spinal, external cuneate, pontine reticular, vestibular, superior and inferior colliculus, locus ceruleus, periaqueductal gray, parabrachial, dorsal raphe, pretectal, lateral lemniscus nuclei, and the contralateral PPN) structures. The DTI obtained from healthy adults showed similar PPN non-motor connections as in rats. Conclusion: Understanding the connections of the PPN with non-motor cortical, subcortical, and brainstem areas of the CNS will enrich our knowledge of its contribution in various circuits and the areas that PPN activity can influence. Further, it will provide insight into the role of Parkinson's disease and related disorders and explain the non-motor complications which occur subsequent to deep brain stimulation (DBS) of the PPN. © 2021Öğe Retraction Note: Comparing astrocytic gap junction of genetic absence epileptic rats with control rats: an experimental study (Brain Structure and Function, (2021), 226, 7, (2113-2123), 10.1007/s00429-021-02310-y)(Springer Science and Business Media Deutschland GmbH, 2023) Çavdar, Safiye; Köse, Büşra; Sur-Erdem, İlknur; Özkan, MazharThe Editors in Chief have retracted this article. After the correction to Fig. 1 was published in January 2022 (Çavdar et al. 2022), the journal was notified about further concerns regarding the images presented there. The authors provided raw data which revealed a number of irregularities in Fig. 1 between the raw data and the submitted figure. For this reason, the Editors in Chief have lost confidence in the integrity of the findings in this article. None of the authors agree to this retraction. © 2023, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.Öğe The brainstem connections of the supplementary motor area and its relations to the corticospinal tract: Experimental rat and human 3-tesla tractography study(Elsevier Ireland Ltd, 2023) Çavdar, Safiye; Köse, Büşra; Altınöz, Damlasu; Özkan, Mazhar; Güneş, Yasin Celal; Algın, OktayAlthough the supplementary motor area (SMA) is a large region on the medial surface of the frontal lobe of the brain, little is known about its function. The current study uses 3-tesla high-resolution diffusion tensor tractography (DTI) in healthy individuals and biotinylated dextran amine (BDA) and fluoro-gold (FG) tracer in rats to demonstrate the afferent and efferent connections of the SMA with brainstem structures. It also aims to clarify how SMA fibers relate to the corticospinal tract (CST). The BDA (n = 6) and FG (n = 8) tracers were pressure-injected into the SMA of 14 Wistar albino rats. Light and fluorescence microscopy was used to capture images of the FG and BDA-labeled cells and axons. High-resolution 3-tesla DTI data were acquired from the Human Connectome Project database. Tracts between the SMA and brainstem structures were analyzed using diffusion spectrum imaging (DSI) studio software. The FG injections into the SMA showed afferent projections from mesencephalic (periaqueductal gray matter, substantia nigra pars reticulata, ventral tegmental area, inferior colliculus, mesencephalic reticular, tegmental, and raphe nuclei), pontine (locus coeruleus, pontine reticular and vestibular nuclei), and medullary (area postrema, parabrachial, and medullary reticular nuclei) structures. The anterograde tracer BDA injections into the SMA showed efferent connections with mesencephalic (periaqueductal gray, substantia nigra pars compacta, dorsal raphe, trigeminal motor mesencephalic, and mesencephalic reticular nuclei), pontine (locus coeruleus, nucleus of the lateral lemniscus, vestibular, cochlear, and pontine reticular nuclei), and medullary (area postrema, medullary reticular, olivary, and parabrachial nuclei) structures. The SMA had efferent but no afferent connections with the cerebellar nuclei. The DTI results in healthy human subjects highly corresponded with the experimental results. Further, the DTI results showed a distinct bundle that descended to spinal levels closely related to the CST. Understanding SMA's afferent and efferent connections will enrich our knowledge of its contribution to various brainstem networks and may provide new perspectives for understanding its motor and non-motor functions. © 2023 Elsevier B.V.Öğe The Change of Oral Presentations of National Anatomy Congresses Over the Years(2023) Özkan, Mazhar; Dinçel, Yaşar MahsutIntroduction: In this study, it is aimed to examine the characteristics and publication rates of oral presentations presented in national congresses. Methods: The data about the oral presentations in national anatomy congresses (from 2016 to 2021), including the number of contributing institutions, the institutions that contributed the most oral presentations each year, and the publication rates of the oral presentations in the journals scanned in different indexes. In the study, the titles and the keywords were scanned using Google Scholar and Web of Science, and journal index details were noted. Results: Of the national congresses we examined in our study, the most oral presentations (193) were the congress in 2019 and the least oral presentations (47) were the congress in 2017. The publication rate of oral presentations was highest in the papers of the congress in 2016 (42%) and at least in the papers of the congress in 2019 (13%). None of the oral presentations in the last congress held in 2021 were published until the time of our study. Large proportions (34%) of the papers that are accepted as oral presen tations and published are radiological studies. 70% of the publications were published in journals indexed in Web of Science. Conclusion: For both new and senior academics, congresses offer a useful and distinctive setting. Congress papers showcase the scientific opportunities and interests of various universities while also providing opportunities for collaboration. Attendance at a conference is significantly influenced by its location, timing, and financial situation.
