Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Hasan Rifat Koyuncuoglu is active.

Publication


Featured researches published by Hasan Rifat Koyuncuoglu.


Molecular and Cellular Biochemistry | 2006

The Activities of Antioxidant Enzymes and the Level of Malondialdehyde in Cerebellum of Rats Subjected to Methotrexate: Protective Effect of Caffeic Acid Phenethyl Ester

Ertugrul Uzar; Hasan Rifat Koyuncuoglu; Efkan Uz; H. Ramazan Yilmaz; Süleyman Kutluhan; Serkan Kilbas; Fatih Gultekin

Methotrexate (MTX), a folic acid antagonist, is widely used as a cytotoxic chemotherapeutic agent. MTX-associated neurotoxicity is an important clinical problem. The aim of this study was to investigate the role of caffeic acid phenethyl ester (CAPE) on cerebellar oxidative stress induced by MTX in rats. A total of 19 adult male rats were divided into three experimental groups as follows: MTX group (MTX treated), MTX+CAPE group (MTX+CAPE treated), and control group. MTX was administered intraperitoneally (i.p.) with a single dose of 20 mg kg−1 on the second day of experiment. CAPE was administered i.p. with a dose of 10 μmol kg−1 day−1 for 7 days. Malondialdehyde (MDA) levels and activities of superoxide dismutase (SOD) and catalase (CAT) were determined in cerebellar tissue of rats. MTX caused to significant increase in MDA levels (an important marker of lipid peroxidation) in the MTX group compared with the controls (p = 0.006). CAPE significantly reduced the MTX induced lipid peroxidation in the MTX+CAPE group compared to the MTX (p = 0.007). The activities of SOD and CAT were significantly increased in the MTX group when compared with the control group (p = 0.0001, p = 0.004, respectively). The increased activities of these enzymes were significantly reduced by CAPE treatment (p = 0.004, p = 0.034, respectively). As a result, CAPE may protect from oxidative damage caused by MTX treatment in rat cerebellum.


Human & Experimental Toxicology | 2008

Caffeic acid phenethyl ester modulates methotrexate-induced oxidative stress in testes of rat.

Abdullah Armagan; Ertugrul Uzar; Efkan Uz; Hr Yilmaz; Süleyman Kutluhan; Hasan Rifat Koyuncuoglu; Sedat Soyupek; H Cam; Ta Serel

The aim of this study was to investigate the possible protective role of caffeic acid phenethyl ester on testicular toxicity of methotrexate in rats. Nineteen male rats were divided into three groups as follows: group I, control; group II, methotrexate-treated; group III, methotrexate + caffeic acid phenethyl ester-treated. In the second day of experiment, a single dose of methotrexate was intraperitoneally administered to groups II and III, although a daily single dose of caffeic acid phenethyl ester was intraperitoneally administered to group III for 7 days. At the end of the experiment, the testes of the animals were removed and weighed. In the tissue, the level of lipid peroxidation as malondialdehyde and activities of superoxide dismutase were higher in the methotrexate group than in the control group. Lipid peroxidation levels and superoxide dismutase activities were decreased in caffeic acid phenethyl ester + methotrexate group compared with methotrexate group. The activities of catalase in the methotrexate group decreased insignificantly although its activities were significantly increased by caffeic acid phenethyl ester administration. The activity of glutathione peroxidase did not change in the groups. There was significant difference in body weight between control and methotrexate-induced groups. In conclusion, the administration of methotrexate causes elevation of oxidative stress although treatment with caffeic acid phenethyl ester has protective effects on the oxidative stress in testes.


International Journal of Neuroscience | 2015

The clinical significance of the neutrophil-to-lymphocyte ratio in multiple sclerosis

Seden Demirci; Serpil Demirci; Süleyman Kutluhan; Hasan Rifat Koyuncuoglu; Vedat Ali Yürekli

Multiple sclerosis (MS) is one of the main chronic inflammatory diseases of the central nervous system that causes functional disability in young people. The aim of this study was to investigate the neutrophil-to-lymphocyte ratio (NLR) in patients with MS and the relationship between the NLR and the severity of the disease. One hundred and two MS patients (31 patients were in relapse; 71 patients were in remission) and 56 healthy controls were included. Complete blood counts as well as demographic and clinical data from MS patients were evaluated retrospectively. The NLRs were calculated for all participants and were compared; the cut-off value was also determined for the NLR and Expanded Disability Status Scale (EDSS). MS patients had a significantly higher NLR (p < 0.001) than the control group. The NLR levels were significantly higher in patients who were in relapse than patients in remission (p = 0.039). The cut-off value for the NLR to predict an MS diagnosis and activity were determined to be 2.04 and 3.90, respectively. The NLRs were directly correlated with erythrocyte sedimentation rate levels (r = 0.795, p < 0.001). Logistic regression analysis with dichotomous EDSS score showed that a high NLR was an independent predictor of the progression of disability. The NLR may be a biomarker that has simple, quick, inexpensive and reproducible properties in MS to predict patients prognosis.


Cornea | 2015

Corneal and Tear Film Changes After Botulinum Toxin-A in Blepharospasm or Hemifacial Spasm.

Alime Gunes; Seden Demirci; Hasan Rifat Koyuncuoglu; Levent Tok; Ozlem Tok

Purpose: To investigate changes in corneal parameters and the tear film after botulinum toxin-A (BTX-A) injection in patients with blepharospasm or hemifacial spasm. Methods: Twelve patients with benign essential blepharospasm and 30 with hemifacial spasm treated with BTX-A were included in this study. Disease severity was evaluated using the Jankovic scale. Corneal parameters were measured by the Pentacam. The Schirmer test score, tear breakup time, corneal fluorescein staining value, and Ocular Surface Disease Index score were also evaluated. Results: The BTX-A treatment relieved spasms in all of the patients. There was a statistically significant difference in disease severity between pretreatment and the third week (2.7 ± 0.8 and 1.3 ± 0.6, respectively; P < 0.001), but there was no statistically significant difference between pretreatment and the third month (2.7 ± 0.8 and 2.7 ± 0.8, respectively; P = 0.8). The tear breakup time was found to be significantly higher at both 3 weeks and 3 months after injection (6.6 ± 4.0 at pretreatment, 8.1 ± 3.9 at the third week, and 7.8 ± 4.2 at the third month; P = 0.04 and P = 0.02, respectively). The Schirmer test score, corneal fluorescein staining values, and Ocular Surface Disease Index score were lower 3 weeks after injection, but these values increased again by 3 months after injection. Corneal astigmatism decreased significantly at 3 weeks and at 3 months after injection [1.4 ± 1.2 diopters (D) at pretreatment, 1.2 ± 0.8 D at the third week, and 1.1 ± 0.8 D at the third month, respectively; P = 0.02, for both], but other corneal parameters did not change. Conclusions: BTX-A injection therapy was affected the tear film in patients with blepharospasm or hemifacial spasm. However, there were no changes in corneal parameters, except corneal astigmatism, in these patients after treatment.


Computers in Biology and Medicine | 2015

Investigation of the relationship between anxiety and heart rate variability in fibromyalgia

Süleyman Bilgin; Evren Arslan; Onur Elmas; Sedat Yildiz; Ömer Halil Çolak; Gürkan Bilgin; Hasan Rifat Koyuncuoglu; Selami Akkuş; Selcuk Comlekci; Etem Koklukaya

BACKGROUND Fibromyalgia syndrome (FMS) is identified by widespread musculoskeletal pain, sleep disturbance, nonrestorative sleep, fatigue, morning stiffness and anxiety. Anxiety is very common in Fibromyalgia and generally leads to a misdiagnosis. Self-rated Beck Anxiety Inventory (BAI) and doctor-rated Hamilton Anxiety Inventory (HAM-A) are frequently used by specialists to determine anxiety that accompanies fibromyalgia. However, these semi-quantitative anxiety tests are still subjective as the tests are scored using doctor-rated or self-rated scales. METHOD In this study, we investigated the relationship between heart rate variability (HRV) frequency subbands and anxiety tests. The study was conducted with 56 FMS patients and 34 healthy controls. BAI and HAM-A test scores were determined for each participant. ECG signals were then recruited and 71 HRV subbands were obtained from these ECG signals using Wavelet Packet Transform (WPT). The subbands and anxiety tests scores were analyzed and compared using multilayer perceptron neural networks (MLPNN). RESULTS The results show that a HRV high frequency (HF) subband in the range of 0.15235Hz to 0.40235Hz, is correlated with BAI scores and another HRV HF subband, frequency range of 0.15235Hz to 0.28907Hz is correlated with HAM-A scores. The overall accuracy is 91.11% for HAM-A and 90% for BAI with MLPNN analysis. CONCLUSION Doctor-rated or self-rated anxiety tests should be supported with quantitative and more objective methods. Our results show that the HRV parameters will be able to support the anxiety tests in the clinical evaluation of fibromyalgia. In other words, HRV parameters can potentially be used as an auxiliary diagnostic method in conjunction with anxiety tests.


Life Sciences | 2016

Physiological parameters as a tool in the diagnosis of fibromyalgia syndrome in females: A preliminary study.

Onur Elmas; Sedat Yildiz; Süleyman Bilgin; Seden Demirci; Selcuk Comlekci; Hasan Rifat Koyuncuoglu; Selami Akkuş; Ömer Halil Çolak; Etem Koklukaya; Evren Arslan; Özhan Özkan; Gürkan Bilgin

AIMS Although fibromyalgia (FM) syndrome is associated with many symptoms, there is as yet no specific finding or laboratory test diagnostic of this syndrome. The physical examination and laboratory tests may be helpful in figuring out this syndrome. MATERIALS AND METHODS The heart rate, respiration rate, body temperature (TEMP), height, body weight, hemoglobin level, erythrocyte sedimentation rate, white blood cell count, platelet count (PLT), rheumatoid factor and C-reactive protein levels and electrocardiograms (ECG) of FM patients were compared with those of control individuals. In addition, the predictive value of these tests was evaluated via receiver operating characteristic (ROC) analysis. KEY FINDINGS The results showed that the TEMP and the PLT were higher in the FM group compared with the control group. Also, ST heights in ECGs which corresponds to a period of ventricle systolic depolarization, showed evidence of a difference between the FM and the control groups. There was no difference observed in terms of the other parameters. According to the ROC analysis, PLT, TEMP and ST height have predictive capacities in FM. SIGNIFICANCE Changes in hormonal factors, peripheral blood circulation, autonomous system activity disorders, inflammatory incidents, etc., may explain the increased TEMP in the FM patients. The high PLT level may signify a thromboproliferation or a possible compensation caused by a PLT functional disorder. ST depression in FM patients may interrelate with coronary pathology. Elucidating the pathophysiology underlying the increases in TEMP and PLT and the decreases in ST height may help to explain the etiology of FM.


Seizure-european Journal of Epilepsy | 2012

Status epilepticus in a 52-year-old woman due to intracranial needle

Vedat Ali Yürekli; Melike Doğan; Süleyman Kutluhan; Hasan Rifat Koyuncuoglu

Intracranial needles are a rare entity. They most commonly present with headache and seizures. The management of such patients is sometimes challenging. We present a 52-year-old woman who was admitted to our hospital with status epilepticus, because of an inracranial needle. There was no history of epileptic seizures and she was asymptomatic until the time of presentation.


Journal of Back and Musculoskeletal Rehabilitation | 2009

The rehabilitation programme of an adult phenylketonuria with upper motor neuron involvement

Feray Soyupek; Hasan Rifat Koyuncuoglu; Abdullah Cindas; Erdem İlgün; Rukiye Tak

Phenylketonuria (PKU) is a disorder characterized by several biochemical mechanisms which may impair the brain functions in PKU, leading to neurological problems. Our case report concerns a 19 year-old man with phenylketonuria who was evaluated with the onset of stiffness following the abandonment of the phenylalanine-restricted diet. He was assessed with grade-4 spasticity according to Modified Aschworth scale. The deep tendon reflexes had increased and the plantar reflexes were positive. Knee extensions were limited due to the shortening of the hamstring muscles. Serum phenylalanine concentration was elevated and plasma vitamin B12 level was low. Cranial magnetic resonance imaging scan revealed demyelinization area in periventricular deep white matter. We administered a phenylalanine-restricted diet and a rehabilitation program. Following the treatment, spasticity was reduced to grade-1 and patient could walk without aid. This case shows that, the combination of diet, medication and a rehabilitation program is an effective treatment model on adult PKU with upper motor neuron involvement.


Polish Journal of Radiology | 2016

Eagle Syndrome Causing Vascular Compression with Cervical Rotation: Case Report

Hakan Demirtaş; Mustafa Kayan; Hasan Rifat Koyuncuoglu; Ahmet Orhan Çelik; Mustafa Kara; Nihat Şengeze

Summary Background Eagle syndrome is a condition caused by an elongated styloid process. Unilateral face, neck and ear pain, stinging pain, foreign body sensation and dysphagia can be observed with this syndrome. Rarely, the elongated styloid process may cause pain by compressing the cervical segment of the internal carotid and the surrounding sympathetic plexus, and that pain spreading along the artery can cause neurological symptoms such as vertigo and syncope. Case Report In this case report we presented a very rare eagle syndrome with neurological symptoms that occurred suddenly with cervical rotation. The symptoms disappeared as suddenly as they occurred, with the release of pressure in neutral position. We also discussed CT angiographic findings of this case. Conclusions Radiological diagnosis of the Eagle syndrome that is manifested with a wide variety of symptoms and causes diagnostic difficulties when it is not considered in the differential diagnosis is easy in patients with specific findings. CT angiography is a fast and effective examination in terms of showing compression in patients with the Eagle syndrome that is considered to be atypical and causes vascular compression.


national biomedical engineering meeting | 2010

Correlation of BAI psychological test scores with heart rate variability using wavelet packet transform and artificial neural networks in fibromyalgia syndrome

Süleyman Bilgin; Ömer Halil Çolak; Gürkan Bilgin; Özhan Özkan; Sedat Yildiz; Etem Koklukaya; Onur Elmas; Selcuk Comlekci; Hasan Rifat Koyuncuoglu; Selami Akkuş

Fibromyalgia syndrome which is appeared in the form of common pain in women is a musculoskeletal disorder. Heart rate variability (HRV) is a signal as measured time between each successive QRS time obtained from ECG signal. HRV parameters are associated with autonomic nervous system in literature. FMS affects patients psychology. Consequently some psychological tests are applied to patients for evaluation of psychological effects. Beck Anxiety Inventory (BAI) Test being applied as writing and speaking is a test consisting of 21 questions. In the study, HRV signals obtained from FMS patients and control group are decomposed into wavelet packets using Wavelet Packet Transform (WPT) and frequency bands which related to autonomic nervous system are included to study. Wavelet Packets within these frequency bands are applied to inputs of multilayer perceptron artificial neural networks (MLPNN). BAI psychological test scores are included as target values for MLPNN and each input is trained and tested as relating to target values. According to obtained accuracy values, the packets within Very Low Frequency (VLF) band has minimum accuracy values, however the packets within Low Frequency + High Frequency (LF+HF) has the best accuracy values. This study is targeted on presenting a solution for clinical studies which are evaluated using psychological test scores by physiological support.

Collaboration


Dive into the Hasan Rifat Koyuncuoglu's collaboration.

Top Co-Authors

Avatar

Süleyman Kutluhan

Süleyman Demirel University

View shared research outputs
Top Co-Authors

Avatar

Vedat Ali Yürekli

Süleyman Demirel University

View shared research outputs
Top Co-Authors

Avatar

Seden Demirci

Süleyman Demirel University

View shared research outputs
Top Co-Authors

Avatar

Galip Akhan

Süleyman Demirel University

View shared research outputs
Top Co-Authors

Avatar

Ertugrul Uzar

Süleyman Demirel University

View shared research outputs
Top Co-Authors

Avatar

Serpil Demirci

Süleyman Demirel University

View shared research outputs
Top Co-Authors

Avatar

Fatih Gultekin

Süleyman Demirel University

View shared research outputs
Top Co-Authors

Avatar

Levent Tok

Süleyman Demirel University

View shared research outputs
Top Co-Authors

Avatar

Ozlem Tok

Süleyman Demirel University

View shared research outputs
Top Co-Authors

Avatar

Selami Akkuş

Süleyman Demirel University

View shared research outputs
Researchain Logo
Decentralizing Knowledge