Sinan Canan - Academia.edu (original) (raw)

Papers by Sinan Canan

Research paper thumbnail of An Unbiased Way to Estimate Total Quantities: The Fractionator Technique

Neuroquantology, Jul 21, 2011

... An Unbiased Way to Estimate Total Quantities: The Fractionator Technique. Suleyman Kaplan, Si... more ... An Unbiased Way to Estimate Total Quantities: The Fractionator Technique. Suleyman Kaplan, Sinan Canan, Muhammed Eyup Altunkaynak, Ersan Odaci, Hüseyin Aslan, Bunyami Unal. Abstract. The fractionator is a straightforward ...

Research paper thumbnail of A stereological investigation on the effects of forebrain ischemia on hippocampal neuron number in chick

Neuroscience Research Communications, 2002

Seven days after 10 minutes bilateral occlusion of internal carotid arteries, the total neuron nu... more Seven days after 10 minutes bilateral occlusion of internal carotid arteries, the total neuron number and the volume of the hippocampus were estimated using the optical fractionator method for cell counting and Cavalieri's principle for volume estimation. After comparing with sham-operated animals, no significant difference in total neuron number was observed in hippocampi of ischemic chicks; a statistically significant increase in numerical density of hippocampal neurons in hippocampi of ischemic group (p<0.05) could well be explained as a decrease, although statistically insignificant, of the hippocampal volume. These results indicate that, the ischemia model and/or its duration is not sufficient to induce a detectable neuronal loss but it induces a reduction in the volume of hippocampus. It also indicates that 10 minutes ischemia is too short a test period to induce a neuronal cell loss in hippocampus of young domestic chicks.

Research paper thumbnail of Davranışın Sinirsel Temelleri

Research paper thumbnail of Volumetric evaluation of temporal bone structures in the cases with bilateral tinnitus: clinical and morphometrical study

Folia Morphologica, Mar 5, 2018

Background: Tinnitus is the recognition of sound in the absence of any external auditory stimulus... more Background: Tinnitus is the recognition of sound in the absence of any external auditory stimulus to the noise of ringing in the ears. Middle ear aeration carries important role for ossicular coupling and normal hearing. There is restricted morphometric data on the cases with bilateral tinnitus. Materials and methods: In this study we evaluated hearing findings of 18 cases with subjective nonpulsatile bilateral tinnitus and also morphometry and volumetry of temporal bone substructures on the computed tomography images using stereological method compared with the gender and age matched 12 healthy subjects. Duration of tinnitus, exposing acoustic trauma or/and high level noise levels, evaluation of middle ear volume, jugular bulb levels, distances between jugular bulb and both oval window and middle ear were evaluated. Results: Both males and females with tinnitus showed worse hearing thresholds through bone and air conductions than healthy subjects but it was not statistically significant. Pure tone thresholds through bone and air conductions were not statistically different in both sexes with bilateral tinnitus. Right middle ear volume of the cases with bilateral tinnitus was mean 5.57 cm 3 for males and 5.64 cm 3 for females; and also the left middle ear volume of the cases with bilateral tinnitus was mean 5.87 cm 3 for males and 5.65 cm 3 for females. There were no significant differences between the cases with bilateral tinnitus and the control subjects according to the side of the body. Conclusions: The data on the hearing findings and morphometrical evaluation of the cases with bilateral tinnitus may be important for anatomists and clinicians.

Research paper thumbnail of A stereological estimation of total neuron number and volume of the hippocampus at one and seven day-old chicks

Neuroscience Research Communications, Jul 1, 2002

Hippocampal complex of the avian brain is one of the most studied brain regions in recent years. ... more Hippocampal complex of the avian brain is one of the most studied brain regions in recent years. This structure is thought to be homologous to mammalian hippocampus and have an important role in spatial memory. Connection patterns between the avian hippocampus and other brain regions strongly support the idea of homology between mammalian and avian hippocampal complexes. Total neuron number of chick hippocampus in different ages was estimated using optical fractionator counting method. Animals were separated into two groups as one day-and seven day-old chicks. The mean total number of nerve cells in the right hippocampi of one day-old and seven day-old chicks was estimated as 783 310 ± 12 749 and 760 028 ± 12 256 respectively. The difference between two groups was not statistically significant (p > 0.05). The mean total volume of hippocampi of chicks was estimated by Cavalieri's principle and it was found to be 2.48 ± 0.08 mm 3 for one day-old chicks and 2.80 ± 0.04 mm 3 for seven day-old chicks. The difference between these volume values was statistically significant (p < 0.01). Although the difference in total neuron numbers between two groups was not raised statistically significant level, decreasing cell number with age might be depend on the destruction of unneeded nerve cells with aging. The increased volume in seven day-old group may be associated with enlargement due to several reasons during development.

Research paper thumbnail of Wavelet Phase Coherence Estimation of EEG Signals for Neuromarketing Studies

Neuroquantology, 2019

This paper presents an Electroencephalography (EEG), Pulse Plethysmography (PPG) and Galvanic Ski... more This paper presents an Electroencephalography (EEG), Pulse Plethysmography (PPG) and Galvanic Skin Response (GSR) study for neuromarketing studies, which are related to analysis of relationship between electrodes and emotional stress across to commercial advertisement. Neuromarketing is a field of study with respect the application of neuroscience methods to analyze consumer behavior related to markets. Wavelet coherence (WC) and phase difference (PD) were used for investigating how the marketing stimuli induced the degree of information flow occurs between electrodes of EEG. Pulse rate variability (PRV) obtained from finger PPG and computed the powers in high frequency (HF), low frequency (LF). The powers in the LF and HF bands are regulated by Autonomic nervous systems (ANS) and then, Skin conductance level (SCL) computed from GSR by measuring changes in the conductivity of the skin. These electrophysiological measurements computed to evaluate emotional stress. The signals were recorded simultaneously from 30 subjects for two stages: prior to advertising stimuli (control stage) and during the advertising stimuli (experimental stage) using iMotions system in Uskudar University (Istanbul, Turkey). The WC and PD for each electrode pairs were computed for five frequency sub-bands (delta, theta, alpha, beta and gamma) of EEG. While the value of WC was generally higher in experimental stage than control stage especially in the theta, alpha and beta frequency, the value of PD was generally lower especially in gamma band. An increase of interhemispheric coherence in experimental stage occurred in the anterior frontal-temporal-parietal-area. At the same time, the LF/HF ratio and SCL were generally higher in experimental stage. We investigated whether there were statistically significant differences in WC, PD, the LF/HF ratio and SCL between the experimental and control stage. Results were demonstrated significant differences in WC and PD, LF/HF ratio between experimental stage and control stage, but there was not in SCL.

Research paper thumbnail of The effect of autogenous vein grafts on nerve repair with size discrepancy in rats: An electrophysiological and stereological analysis

Brain Research, Mar 1, 2008

The heterotopic transfer of autologous tissues is likely to result in a size discrepancy between ... more The heterotopic transfer of autologous tissues is likely to result in a size discrepancy between the donor and recipient nerves, which will have a negative influence on regeneration. Twenty Wistar albino female rats were used in a study that was divided into two main groups: tibial-peroneal (TP) and peroneal-tibial repair (PT). Both types of nerves were exposed on the hind legs with the nerves cut on the right side, while the proximal stump of the tibial nerve and distal stump of the peroneal nerve were sutured to each other. These groups are also called end-to-end neurorrhaphy groups (EtoE). On the left side, the tibial and peroneal nerves were cut on the same level as on the right side. After the end-to-end epineural suturing of the nerve, the vein graft was slid over to the repair zone under irrigation. These are called the vein graft group (VG). All processes mentioned above were also done for the PT group. On the 90th postoperative day, anesthetized animals were fixed prone on a board, with the nerves carefully dissected for electrophysiological recording. Stereological methods for an estimation of the total number of myelinated fiber, a mean axonal cross-section area and the thickness of the myelin sheet were used. In TP and PT groups, nerve conduction velocities were found to be higher within the VG group. Nevertheless; the difference was only significant in the PT group. In both TP and PT groups, the increase in the axon number, axon area and myelin thickness were statistically different in favor of the vein graft sides. An appearance of vacuoles and degenerated pertinacious material within the myelin sheath of EtoE sides was seen. A histomorphological examination of the sections proximal to, from, and distal to the repair zone over three months revealed less epineural scarring, a thinner epineurium, more regenerated axons and

Research paper thumbnail of Stereological evaluation of volumetric asymmetry in healthy human cerebellum

Surgical and Radiologic Anatomy, Oct 22, 2008

Objectives Age-related volumetric differences in brain anatomy or volumetric brain analyses in ma... more Objectives Age-related volumetric differences in brain anatomy or volumetric brain analyses in many disorders are of interest. Delineating the normal anatomical cerebellar volume is of importance for both the anatomists and clinicians. In the present study, we aimed to evaluate the cerebellar volume using a stereological technique and to determine the possible volumetric asymmetry depending on age and gender. Materials and methods Volumetric asymmetry of cerebellar hemispheres was evaluated using stereological method on the magnetic resonance images (MRI) of healthy male and female subjects. Randomly selected individuals (27 males, 27 females) aged between 10-86 years who have normal brain MRI were enclosed in the study. All the subjects were right handed. The individuals were divided into three groups according to age as 18-34 (young), 35-60 (middle aged) and 60-84 (elder) and their MRI images were analyzed. The data set were analyzed by two factor repeated measure analysis. Results Although the cerebellum was smaller between young and middle aged groups and also middle aged and elder groups, there were no any statistically significant differences between compared groups' mean (P [ 0.05). There were not statistically differences according to sex and age groups (P [ 0.05). Conclusions There was no cerebellar asymmetry between compared groups. The stereological evaluation of cerebellar asymmetry in humans correlate with both gender and age groups is of importance for both clinicians and anatomists. The technique is simple, reliable, unbiased and inexpensive.

Research paper thumbnail of Estimation of numerical density and mean synaptic height in chick hippocampus 24 and 48 hours after passive avoidance training

Developmental Brain Research, Jun 1, 2002

The effects of passive avoidance learning on synaptic morphology and number in the dorsolateral h... more The effects of passive avoidance learning on synaptic morphology and number in the dorsolateral hippocampus of chick were investigated at 24 and 48 h after training. Chicks of both sexes were used. The numerical density of synapses and mean synaptic height were determined using design-based quantitative electron microscopic techniques. Our results suggest that after training there is a significant increase in synaptic density in the dorsolateral hippocampus of chicks at both 24 and 48 h, and also that the mean synaptic height was significantly different between trained and control groups. The increase in synaptic density was due to shaft (type II) synapses. It is known that during synaptogenesis, shaft synapses are formed first and are then converted to spine synapses. The only hemispheric asymmetry was found in the 24 h water-trained (W-trained) males where the numerical density of spine synapses was significantly higher in the left hippocampus. No significant differences due to gender in either numerical synaptic density or synapse height were observed at either 24 and 48 h. Comparison of the 24 h with 48 h groups showed an increase in shaft synaptic density over time in the W-trained groups, and an increased density of both shaft and spine synapses with time in methylanthranilate-trained (MeA-trained) chicks. These results demonstrate that the dorsolateral hippocampus of the chick shows synaptic changes at both 24 and 48 h after training and implicates this region in the long-term memory process.

Research paper thumbnail of Biyolojik Ortamlardaki Objelerin Sayımı Yapılırken Kullanılan Eski (Taraflı) Metodların Önemli Hata Kaynakları ve Çözüm Önerileri

Turkiye Klinikleri Tip Bilimleri Dergisi, 2002

Özet Doku içindeki hücre veya hücre içi elemanlarının sayısı bulunmak istendiğinde, yapı kesitler... more Özet Doku içindeki hücre veya hücre içi elemanlarının sayısı bulunmak istendiğinde, yapı kesitler haline getirilerek mikroskop altında incelenir. Alınan doku kesitlerinde derinlik boyutu göz ardı edildiğinde, yapı içindeki objelerle ilgili bilgiler ancak objelerin kesitteki iki ...

Research paper thumbnail of The Disector Counting Technique

Neuroquantology, Jul 21, 2011

Research paper thumbnail of Unbiased Stereological Techniques

Neuroquantology, Jul 21, 2011

Research paper thumbnail of A comparison of facial soft tissue thickness in Anatolian pre-pubertal and post-pubertal subjects in relation to different facial patterns

Anatomy, 2011

Objectives: Facial soft tissue thickness is important for forensic anthropologists, dentists and ... more Objectives: Facial soft tissue thickness is important for forensic anthropologists, dentists and plastic surgeons. Forensic anthropologists use such information as a reference in facial reconstruction and superimposition. The purpose of this study was to measure facial tissue thicknesses separately for pre-puberty and post-puberty subjects with Turkish origins across different malocclusion types and to compare the results with each other and with values obtained for other races. Methods: The study was conducted on 402 healthy subjects. Facial tissue thicknesses were measured at 10 cephalometric landmarks in a computerized environment. Gender-based variations in facial tissue thickness were noted in prepubertal and postpubertal subjects. Results: Many facial tissue thickness values were observed to change in pre-puberty and post-puberty periods with respect to gender. In general, values were found to be higher in post-puberty males. Differences values were found to be the lowest for Class I and Class III females. Conclusion: Facial tissue thickness in both pre-puberty and post-puberty periods changes with respect to malocclusion types.

Research paper thumbnail of Volumetric evaluation of temporal bone structures in the cases with bilateral tinnitus: clinical and morphometrical study

Folia morphologica, Jan 27, 2017

Tinnitus is the recognition of sound in the absence of any external auditory stimulus to the nois... more Tinnitus is the recognition of sound in the absence of any external auditory stimulus to the noise of ringing in the ears. Middle ear aeration carries important role for ossicular coupling and normal hearing. There is restricted morphometric data on the cases with bilateral tinnitus. In this study we evaluated hearing findings of 18 cases with subjective nonpulsatile bilateral tinnitus and also morphometry and volumetry of temporal bone substructures on the Computed Tomography images using Stereological Method compared with the gender and age matched 12 healthy subjects. Duration of tinnitus, exposing acoustic trauma or/and high level noise levels, evaluation of middle ear volume, jugular bulb levels, distance between jugular bulb and both oval window, middle ear were evaluated. Both males and females with tinnitus showed worse hearing thresholds through bone and air conductions than healthy subjects but it was not statistically significant. Pure tone tresholds through bone and air ...

Research paper thumbnail of Post-Natal Growth in the Rat Pineal Gland: A Stereological Study

Anatomia Histologia Embryologia, Mar 4, 2012

The purpose was to observe the changes in a rat pineal gland using stereological techniques durin... more The purpose was to observe the changes in a rat pineal gland using stereological techniques during lactation and post-weaning periods. Thirty Wistar albino rats were studied during different post-natal periods using light microscopy. Pineal gland volume was estimated using the Cavalieri Method. Additionally, the total number of pinealocytes was estimated using the optical fractionator technique. Pineal gland volume displayed statistically significant changes between lactation and after weaning periods. A significant increase in pineal gland volume was observed from post-natal day 10 to post-natal day 90. The numerical density of pinealocytes became stabilized during lactation and decreased rapidly after weaning. However, the total number of pinealocytes continuously increased during post-natal life of all rats in the study. However, this increment was not statistically significant when comparing the lactation and after weaning periods. The increase in post-natal pineal gland volume may depend on increment of immunoreactive fibres, capsule thickness or new synaptic bodies.

Research paper thumbnail of Davranışın Sinirsel Temelleri

Research paper thumbnail of Yapay Sinir Ağlarına Genel Bakış

Turkiye Klinikleri Tip Bilimleri Dergisi, 2007

Research paper thumbnail of Liberalizm Üzerine Soruşturma

Sorusturma Sorulari 1. Liberalizm denince ne anliyorsunuz? 2. Liberalizmin siyasi ve iktisadi tez... more Sorusturma Sorulari 1. Liberalizm denince ne anliyorsunuz? 2. Liberalizmin siyasi ve iktisadi tezahurleri hakkinda ne soylenebilir? Bunlar birbiriyle nasil bir iliski icindedir? 3. Islam ile liberalizm arasindaki iliskileri nasil degerlendiriyorsunuz? Bu iki olgu birbirinin ziddi midir, alternatifi mi, tamamlayicisi mi? 4. Sizce liberalizm Turkiye'nin bugunku sorunlarina cozum getirebilir mi? 5. Batinin gelismisligi ya da refahi ile Dogu'n un (bu arada Islam dunyasinin) gorece geri kalmisligi veya yoksullugunu aciklamada liberalizmin bir rolu var midir? 6. Sizce Musluman ulkelerde liberal gorusler, parti­ ler veya programlarin tutunma ve koksalma sansi var midir?

Research paper thumbnail of E of numerical density and mean synaptic height in chick

The effects of passive avoidance learning on synaptic morphology and number in the dorsolateral h... more The effects of passive avoidance learning on synaptic morphology and number in the dorsolateral hippocampus of chick were investigated at 24 and 48 h after training. Chicks of both sexes were used. The numerical density of synapses and mean synaptic height were determined using design-based quantitative electron microscopic techniques. Our results suggest that after training there is a significant increase in synaptic density in the dorsolateral hippocampus of chicks at both 24 and 48 h, and also that the mean synaptic height was significantly different between trained and control groups. The increase in synaptic density was due to shaft (type II) synapses. It is known that during synaptogenesis, shaft synapses are formed first and are then converted to spine synapses. The only hemispheric asymmetry was found in the 24 h water-trained (W-trained) males where the numerical density of spine synapses was significantly higher in the left hippocampus. No significant differences due to ge...

Research paper thumbnail of Effects of neurofeedback therapy in healthy young subjects

Clinical & Investigative Medicine, 2016

Purpose: Neurofeedback refers to a form of operant conditioning of electrical brain activity, in ... more Purpose: Neurofeedback refers to a form of operant conditioning of electrical brain activity, in which desirable brain activity is rewarded and undesirable brain activity is inhibited. The research team aimed to examine the efficacy of neurofeedback therapy on electroencephalogram (EEG) for heart rate, electrocardiogram (ECG) and galvanic skin resistance (GSR) parameters in a healthy young male population. Methods: Forty healthy young male subjects aged between 18 to 30 years participated in this study. Neurofeedback application of one session was made with bipolar electrodes placed on T3 and T4 (temporal 3 and 4) regions and with reference electrode placed on PF1 (prefrontal 1). Electroencephalogram (EEG), electrocardiogram (ECG) and galvanic skin resistance (GSR) were assessed during Othmer neurofeedback application of one session to regulate slow wave activity for forty minutes thorough the session. Data assessed before neurofeedback application for 5 minutes and during neurofeed...

Research paper thumbnail of An Unbiased Way to Estimate Total Quantities: The Fractionator Technique

Neuroquantology, Jul 21, 2011

... An Unbiased Way to Estimate Total Quantities: The Fractionator Technique. Suleyman Kaplan, Si... more ... An Unbiased Way to Estimate Total Quantities: The Fractionator Technique. Suleyman Kaplan, Sinan Canan, Muhammed Eyup Altunkaynak, Ersan Odaci, Hüseyin Aslan, Bunyami Unal. Abstract. The fractionator is a straightforward ...

Research paper thumbnail of A stereological investigation on the effects of forebrain ischemia on hippocampal neuron number in chick

Neuroscience Research Communications, 2002

Seven days after 10 minutes bilateral occlusion of internal carotid arteries, the total neuron nu... more Seven days after 10 minutes bilateral occlusion of internal carotid arteries, the total neuron number and the volume of the hippocampus were estimated using the optical fractionator method for cell counting and Cavalieri's principle for volume estimation. After comparing with sham-operated animals, no significant difference in total neuron number was observed in hippocampi of ischemic chicks; a statistically significant increase in numerical density of hippocampal neurons in hippocampi of ischemic group (p<0.05) could well be explained as a decrease, although statistically insignificant, of the hippocampal volume. These results indicate that, the ischemia model and/or its duration is not sufficient to induce a detectable neuronal loss but it induces a reduction in the volume of hippocampus. It also indicates that 10 minutes ischemia is too short a test period to induce a neuronal cell loss in hippocampus of young domestic chicks.

Research paper thumbnail of Davranışın Sinirsel Temelleri

Research paper thumbnail of Volumetric evaluation of temporal bone structures in the cases with bilateral tinnitus: clinical and morphometrical study

Folia Morphologica, Mar 5, 2018

Background: Tinnitus is the recognition of sound in the absence of any external auditory stimulus... more Background: Tinnitus is the recognition of sound in the absence of any external auditory stimulus to the noise of ringing in the ears. Middle ear aeration carries important role for ossicular coupling and normal hearing. There is restricted morphometric data on the cases with bilateral tinnitus. Materials and methods: In this study we evaluated hearing findings of 18 cases with subjective nonpulsatile bilateral tinnitus and also morphometry and volumetry of temporal bone substructures on the computed tomography images using stereological method compared with the gender and age matched 12 healthy subjects. Duration of tinnitus, exposing acoustic trauma or/and high level noise levels, evaluation of middle ear volume, jugular bulb levels, distances between jugular bulb and both oval window and middle ear were evaluated. Results: Both males and females with tinnitus showed worse hearing thresholds through bone and air conductions than healthy subjects but it was not statistically significant. Pure tone thresholds through bone and air conductions were not statistically different in both sexes with bilateral tinnitus. Right middle ear volume of the cases with bilateral tinnitus was mean 5.57 cm 3 for males and 5.64 cm 3 for females; and also the left middle ear volume of the cases with bilateral tinnitus was mean 5.87 cm 3 for males and 5.65 cm 3 for females. There were no significant differences between the cases with bilateral tinnitus and the control subjects according to the side of the body. Conclusions: The data on the hearing findings and morphometrical evaluation of the cases with bilateral tinnitus may be important for anatomists and clinicians.

Research paper thumbnail of A stereological estimation of total neuron number and volume of the hippocampus at one and seven day-old chicks

Neuroscience Research Communications, Jul 1, 2002

Hippocampal complex of the avian brain is one of the most studied brain regions in recent years. ... more Hippocampal complex of the avian brain is one of the most studied brain regions in recent years. This structure is thought to be homologous to mammalian hippocampus and have an important role in spatial memory. Connection patterns between the avian hippocampus and other brain regions strongly support the idea of homology between mammalian and avian hippocampal complexes. Total neuron number of chick hippocampus in different ages was estimated using optical fractionator counting method. Animals were separated into two groups as one day-and seven day-old chicks. The mean total number of nerve cells in the right hippocampi of one day-old and seven day-old chicks was estimated as 783 310 ± 12 749 and 760 028 ± 12 256 respectively. The difference between two groups was not statistically significant (p > 0.05). The mean total volume of hippocampi of chicks was estimated by Cavalieri's principle and it was found to be 2.48 ± 0.08 mm 3 for one day-old chicks and 2.80 ± 0.04 mm 3 for seven day-old chicks. The difference between these volume values was statistically significant (p < 0.01). Although the difference in total neuron numbers between two groups was not raised statistically significant level, decreasing cell number with age might be depend on the destruction of unneeded nerve cells with aging. The increased volume in seven day-old group may be associated with enlargement due to several reasons during development.

Research paper thumbnail of Wavelet Phase Coherence Estimation of EEG Signals for Neuromarketing Studies

Neuroquantology, 2019

This paper presents an Electroencephalography (EEG), Pulse Plethysmography (PPG) and Galvanic Ski... more This paper presents an Electroencephalography (EEG), Pulse Plethysmography (PPG) and Galvanic Skin Response (GSR) study for neuromarketing studies, which are related to analysis of relationship between electrodes and emotional stress across to commercial advertisement. Neuromarketing is a field of study with respect the application of neuroscience methods to analyze consumer behavior related to markets. Wavelet coherence (WC) and phase difference (PD) were used for investigating how the marketing stimuli induced the degree of information flow occurs between electrodes of EEG. Pulse rate variability (PRV) obtained from finger PPG and computed the powers in high frequency (HF), low frequency (LF). The powers in the LF and HF bands are regulated by Autonomic nervous systems (ANS) and then, Skin conductance level (SCL) computed from GSR by measuring changes in the conductivity of the skin. These electrophysiological measurements computed to evaluate emotional stress. The signals were recorded simultaneously from 30 subjects for two stages: prior to advertising stimuli (control stage) and during the advertising stimuli (experimental stage) using iMotions system in Uskudar University (Istanbul, Turkey). The WC and PD for each electrode pairs were computed for five frequency sub-bands (delta, theta, alpha, beta and gamma) of EEG. While the value of WC was generally higher in experimental stage than control stage especially in the theta, alpha and beta frequency, the value of PD was generally lower especially in gamma band. An increase of interhemispheric coherence in experimental stage occurred in the anterior frontal-temporal-parietal-area. At the same time, the LF/HF ratio and SCL were generally higher in experimental stage. We investigated whether there were statistically significant differences in WC, PD, the LF/HF ratio and SCL between the experimental and control stage. Results were demonstrated significant differences in WC and PD, LF/HF ratio between experimental stage and control stage, but there was not in SCL.

Research paper thumbnail of The effect of autogenous vein grafts on nerve repair with size discrepancy in rats: An electrophysiological and stereological analysis

Brain Research, Mar 1, 2008

The heterotopic transfer of autologous tissues is likely to result in a size discrepancy between ... more The heterotopic transfer of autologous tissues is likely to result in a size discrepancy between the donor and recipient nerves, which will have a negative influence on regeneration. Twenty Wistar albino female rats were used in a study that was divided into two main groups: tibial-peroneal (TP) and peroneal-tibial repair (PT). Both types of nerves were exposed on the hind legs with the nerves cut on the right side, while the proximal stump of the tibial nerve and distal stump of the peroneal nerve were sutured to each other. These groups are also called end-to-end neurorrhaphy groups (EtoE). On the left side, the tibial and peroneal nerves were cut on the same level as on the right side. After the end-to-end epineural suturing of the nerve, the vein graft was slid over to the repair zone under irrigation. These are called the vein graft group (VG). All processes mentioned above were also done for the PT group. On the 90th postoperative day, anesthetized animals were fixed prone on a board, with the nerves carefully dissected for electrophysiological recording. Stereological methods for an estimation of the total number of myelinated fiber, a mean axonal cross-section area and the thickness of the myelin sheet were used. In TP and PT groups, nerve conduction velocities were found to be higher within the VG group. Nevertheless; the difference was only significant in the PT group. In both TP and PT groups, the increase in the axon number, axon area and myelin thickness were statistically different in favor of the vein graft sides. An appearance of vacuoles and degenerated pertinacious material within the myelin sheath of EtoE sides was seen. A histomorphological examination of the sections proximal to, from, and distal to the repair zone over three months revealed less epineural scarring, a thinner epineurium, more regenerated axons and

Research paper thumbnail of Stereological evaluation of volumetric asymmetry in healthy human cerebellum

Surgical and Radiologic Anatomy, Oct 22, 2008

Objectives Age-related volumetric differences in brain anatomy or volumetric brain analyses in ma... more Objectives Age-related volumetric differences in brain anatomy or volumetric brain analyses in many disorders are of interest. Delineating the normal anatomical cerebellar volume is of importance for both the anatomists and clinicians. In the present study, we aimed to evaluate the cerebellar volume using a stereological technique and to determine the possible volumetric asymmetry depending on age and gender. Materials and methods Volumetric asymmetry of cerebellar hemispheres was evaluated using stereological method on the magnetic resonance images (MRI) of healthy male and female subjects. Randomly selected individuals (27 males, 27 females) aged between 10-86 years who have normal brain MRI were enclosed in the study. All the subjects were right handed. The individuals were divided into three groups according to age as 18-34 (young), 35-60 (middle aged) and 60-84 (elder) and their MRI images were analyzed. The data set were analyzed by two factor repeated measure analysis. Results Although the cerebellum was smaller between young and middle aged groups and also middle aged and elder groups, there were no any statistically significant differences between compared groups' mean (P [ 0.05). There were not statistically differences according to sex and age groups (P [ 0.05). Conclusions There was no cerebellar asymmetry between compared groups. The stereological evaluation of cerebellar asymmetry in humans correlate with both gender and age groups is of importance for both clinicians and anatomists. The technique is simple, reliable, unbiased and inexpensive.

Research paper thumbnail of Estimation of numerical density and mean synaptic height in chick hippocampus 24 and 48 hours after passive avoidance training

Developmental Brain Research, Jun 1, 2002

The effects of passive avoidance learning on synaptic morphology and number in the dorsolateral h... more The effects of passive avoidance learning on synaptic morphology and number in the dorsolateral hippocampus of chick were investigated at 24 and 48 h after training. Chicks of both sexes were used. The numerical density of synapses and mean synaptic height were determined using design-based quantitative electron microscopic techniques. Our results suggest that after training there is a significant increase in synaptic density in the dorsolateral hippocampus of chicks at both 24 and 48 h, and also that the mean synaptic height was significantly different between trained and control groups. The increase in synaptic density was due to shaft (type II) synapses. It is known that during synaptogenesis, shaft synapses are formed first and are then converted to spine synapses. The only hemispheric asymmetry was found in the 24 h water-trained (W-trained) males where the numerical density of spine synapses was significantly higher in the left hippocampus. No significant differences due to gender in either numerical synaptic density or synapse height were observed at either 24 and 48 h. Comparison of the 24 h with 48 h groups showed an increase in shaft synaptic density over time in the W-trained groups, and an increased density of both shaft and spine synapses with time in methylanthranilate-trained (MeA-trained) chicks. These results demonstrate that the dorsolateral hippocampus of the chick shows synaptic changes at both 24 and 48 h after training and implicates this region in the long-term memory process.

Research paper thumbnail of Biyolojik Ortamlardaki Objelerin Sayımı Yapılırken Kullanılan Eski (Taraflı) Metodların Önemli Hata Kaynakları ve Çözüm Önerileri

Turkiye Klinikleri Tip Bilimleri Dergisi, 2002

Özet Doku içindeki hücre veya hücre içi elemanlarının sayısı bulunmak istendiğinde, yapı kesitler... more Özet Doku içindeki hücre veya hücre içi elemanlarının sayısı bulunmak istendiğinde, yapı kesitler haline getirilerek mikroskop altında incelenir. Alınan doku kesitlerinde derinlik boyutu göz ardı edildiğinde, yapı içindeki objelerle ilgili bilgiler ancak objelerin kesitteki iki ...

Research paper thumbnail of The Disector Counting Technique

Neuroquantology, Jul 21, 2011

Research paper thumbnail of Unbiased Stereological Techniques

Neuroquantology, Jul 21, 2011

Research paper thumbnail of A comparison of facial soft tissue thickness in Anatolian pre-pubertal and post-pubertal subjects in relation to different facial patterns

Anatomy, 2011

Objectives: Facial soft tissue thickness is important for forensic anthropologists, dentists and ... more Objectives: Facial soft tissue thickness is important for forensic anthropologists, dentists and plastic surgeons. Forensic anthropologists use such information as a reference in facial reconstruction and superimposition. The purpose of this study was to measure facial tissue thicknesses separately for pre-puberty and post-puberty subjects with Turkish origins across different malocclusion types and to compare the results with each other and with values obtained for other races. Methods: The study was conducted on 402 healthy subjects. Facial tissue thicknesses were measured at 10 cephalometric landmarks in a computerized environment. Gender-based variations in facial tissue thickness were noted in prepubertal and postpubertal subjects. Results: Many facial tissue thickness values were observed to change in pre-puberty and post-puberty periods with respect to gender. In general, values were found to be higher in post-puberty males. Differences values were found to be the lowest for Class I and Class III females. Conclusion: Facial tissue thickness in both pre-puberty and post-puberty periods changes with respect to malocclusion types.

Research paper thumbnail of Volumetric evaluation of temporal bone structures in the cases with bilateral tinnitus: clinical and morphometrical study

Folia morphologica, Jan 27, 2017

Tinnitus is the recognition of sound in the absence of any external auditory stimulus to the nois... more Tinnitus is the recognition of sound in the absence of any external auditory stimulus to the noise of ringing in the ears. Middle ear aeration carries important role for ossicular coupling and normal hearing. There is restricted morphometric data on the cases with bilateral tinnitus. In this study we evaluated hearing findings of 18 cases with subjective nonpulsatile bilateral tinnitus and also morphometry and volumetry of temporal bone substructures on the Computed Tomography images using Stereological Method compared with the gender and age matched 12 healthy subjects. Duration of tinnitus, exposing acoustic trauma or/and high level noise levels, evaluation of middle ear volume, jugular bulb levels, distance between jugular bulb and both oval window, middle ear were evaluated. Both males and females with tinnitus showed worse hearing thresholds through bone and air conductions than healthy subjects but it was not statistically significant. Pure tone tresholds through bone and air ...

Research paper thumbnail of Post-Natal Growth in the Rat Pineal Gland: A Stereological Study

Anatomia Histologia Embryologia, Mar 4, 2012

The purpose was to observe the changes in a rat pineal gland using stereological techniques durin... more The purpose was to observe the changes in a rat pineal gland using stereological techniques during lactation and post-weaning periods. Thirty Wistar albino rats were studied during different post-natal periods using light microscopy. Pineal gland volume was estimated using the Cavalieri Method. Additionally, the total number of pinealocytes was estimated using the optical fractionator technique. Pineal gland volume displayed statistically significant changes between lactation and after weaning periods. A significant increase in pineal gland volume was observed from post-natal day 10 to post-natal day 90. The numerical density of pinealocytes became stabilized during lactation and decreased rapidly after weaning. However, the total number of pinealocytes continuously increased during post-natal life of all rats in the study. However, this increment was not statistically significant when comparing the lactation and after weaning periods. The increase in post-natal pineal gland volume may depend on increment of immunoreactive fibres, capsule thickness or new synaptic bodies.

Research paper thumbnail of Davranışın Sinirsel Temelleri

Research paper thumbnail of Yapay Sinir Ağlarına Genel Bakış

Turkiye Klinikleri Tip Bilimleri Dergisi, 2007

Research paper thumbnail of Liberalizm Üzerine Soruşturma

Sorusturma Sorulari 1. Liberalizm denince ne anliyorsunuz? 2. Liberalizmin siyasi ve iktisadi tez... more Sorusturma Sorulari 1. Liberalizm denince ne anliyorsunuz? 2. Liberalizmin siyasi ve iktisadi tezahurleri hakkinda ne soylenebilir? Bunlar birbiriyle nasil bir iliski icindedir? 3. Islam ile liberalizm arasindaki iliskileri nasil degerlendiriyorsunuz? Bu iki olgu birbirinin ziddi midir, alternatifi mi, tamamlayicisi mi? 4. Sizce liberalizm Turkiye'nin bugunku sorunlarina cozum getirebilir mi? 5. Batinin gelismisligi ya da refahi ile Dogu'n un (bu arada Islam dunyasinin) gorece geri kalmisligi veya yoksullugunu aciklamada liberalizmin bir rolu var midir? 6. Sizce Musluman ulkelerde liberal gorusler, parti­ ler veya programlarin tutunma ve koksalma sansi var midir?

Research paper thumbnail of E of numerical density and mean synaptic height in chick

The effects of passive avoidance learning on synaptic morphology and number in the dorsolateral h... more The effects of passive avoidance learning on synaptic morphology and number in the dorsolateral hippocampus of chick were investigated at 24 and 48 h after training. Chicks of both sexes were used. The numerical density of synapses and mean synaptic height were determined using design-based quantitative electron microscopic techniques. Our results suggest that after training there is a significant increase in synaptic density in the dorsolateral hippocampus of chicks at both 24 and 48 h, and also that the mean synaptic height was significantly different between trained and control groups. The increase in synaptic density was due to shaft (type II) synapses. It is known that during synaptogenesis, shaft synapses are formed first and are then converted to spine synapses. The only hemispheric asymmetry was found in the 24 h water-trained (W-trained) males where the numerical density of spine synapses was significantly higher in the left hippocampus. No significant differences due to ge...

Research paper thumbnail of Effects of neurofeedback therapy in healthy young subjects

Clinical & Investigative Medicine, 2016

Purpose: Neurofeedback refers to a form of operant conditioning of electrical brain activity, in ... more Purpose: Neurofeedback refers to a form of operant conditioning of electrical brain activity, in which desirable brain activity is rewarded and undesirable brain activity is inhibited. The research team aimed to examine the efficacy of neurofeedback therapy on electroencephalogram (EEG) for heart rate, electrocardiogram (ECG) and galvanic skin resistance (GSR) parameters in a healthy young male population. Methods: Forty healthy young male subjects aged between 18 to 30 years participated in this study. Neurofeedback application of one session was made with bipolar electrodes placed on T3 and T4 (temporal 3 and 4) regions and with reference electrode placed on PF1 (prefrontal 1). Electroencephalogram (EEG), electrocardiogram (ECG) and galvanic skin resistance (GSR) were assessed during Othmer neurofeedback application of one session to regulate slow wave activity for forty minutes thorough the session. Data assessed before neurofeedback application for 5 minutes and during neurofeed...