61 results on '"Firat AK"'
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2. Role of urine glycosaminoglycan levels in the diagnosis and follow-up in men with lower urinary tract symptoms
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Hasan Riza Aydin, Cagri Akin Sekerci, Huseyin Kocakgol, Banu Isbilen Basok, Fevzi Bedir, Ahmet Ozgur Guctas, Firat Akdeniz, Hamit Zafer Aksoy, Mehmet Akif Ramazanoglu, and Yiloren Tanidir
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GAG ,bladder outlet obstruction ,overactive bladder ,biomarker ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Objective: The aim of this study was to investigate whether urinary glycosaminoglycans (GAG) levels reflect clinical status in men with lower urinary tract symptoms and if they could be used as a marker in management of overactive bladder (OAB). Methods: A total of 34 patients were recruited who were admitted with LUTS and diagnosed as having clinically bladder outlet obstruction (BOO) due to prostate enlargement. These newly diagnosed, never treated patients underwent routine investigation, consisting of history, physical examination, PSA, ultrasound, uroflowmetry, assessment of symptoms scored by both International Prostate Symptom Score (IPSS) and Marmara- Overactive Bladder Questionnaire (M-OBQ). The patients were divided into two groups as those with an initial M-OBQ score < 12 (group 1) and ≥ 13 (group 2). Alfa blocker was initiated in eligible patients. Further evaluations included prostate volume measurement, pre- and post-treatment urinary GAG levels, IPSS and M-QAOB values and maximum urine flow rate (Qmax). Results: Before treatment, urinary GAG level was 21.5 mg/gCr (6.1-45.5) in Group 1, and 23.35 mg/gCr (15.6-32.6) in Group 2 (p =0.845). After the treatment, the GAG level in Group 1 and Group 2 were found to be 19.8 mg/gCr (7.4-70.5) and 18 (7.6- 41.7), respectively (p = 0.511). No difference in GAG levels was found in subgroup analysis for patients with or without OAB. Conclusions: In recent years, there have been many studies investigating the relationship between LUTS and urinary markers. However, in our prospective study, no relationship was found between pre- and post- treatment urinary GAG levels in patients with LUTS with or without OAB.
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- 2024
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3. Analysis of Solid Insulating Materials Breakdown Voltages Under Different Voltage Types
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Firat Akın, Oktay Arıkan, and Cihat Çağdaş Uydur
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Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Published
- 2022
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4. STIM1-Orai1 interaction mediated calcium influx activation contributes to cardiac contractility of insulin-resistant rats
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Aysegul Durak, Yusuf Olgar, Kardelen Genc, Erkan Tuncay, Fırat Akat, Sinan Degirmenci, and Belma Turan
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SOCE ,Cardiac ,Calcium ,Metabolic syndrome ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Purpose Metabolic syndrome (MetS) became a tremendous public health burden in the last decades. Store-operated calcium entry (SOCE) is a unique mechanism that causes a calcium influx, which is triggered by calcium store depletion. MetS-induced alterations in cardiac calcium signaling, especially in SOCE are still unclear. Therefore, we aim to examine the possible role of SOCE and its components (STIM1 and Orai1) in the MetS-induced cardiac remodeling. Methods We used male, adult (12 weeks) Wistar albino rats (n = 20). Animals were randomly divided into two groups which were: control (C) and MetS. We gave 33% sucrose solution to animals instead of water for 24 weeks to establish MetS model. In the end, papillary muscle function was evaluated, and various electrophysiological analyses were made in isolated cardiomyocytes. Additionally, STIM1 and Orai1 protein and mRNA expressions were analyzed. Results We observed a deterioration in contractility in MetS animals and demonstrated the contribution of SOCE by applying a SOCE inhibitor (BTP2). Calcium spark frequency was increased while its amplitude was decreasing in MetS hearts, which was reversed after SOCE inhibition. The amplitude of transient calcium changes in the MetS group was decreased, and it decreased further BTP2 application. Both protein and mRNA levels of STIM1 and Orai1 were increased significantly in MetS hearts. Conclusion Current data indicate the significant contribution of SOCE to cardiac calcium handling in the MetS model. We think MetS-induced SOCE activation is a compensation mechanism that is required for the continuum of proper cardiac functioning, although the activation can also cause cardiac hypertrophy.
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- 2022
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5. The effects of six-week slow, controlled breathing exercises on heart rate variability in physically active, healthy individuals
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Cihan Erdem Sürücü, Sarp Güner, Caner Cüce, Dicle Aras, Fırat Akça, Erşan Arslan, Abdulkadir Birol, and Alkan Uğurlu
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heart rate variability ,breathing exercise ,autonomic nervous system ,Special aspects of education ,LC8-6691 ,Sports ,GV557-1198.995 - Abstract
Background and Study Aim: Heart rate variability (HRV) provides information about sympathetic-parasympathetic balance. The effects of different types of physical exercises on HRV have been investigated so far. The purpose of the current study was to evaluate the chronic effects of six-week slow and controlled breathing exercise on HRV in physically active, healthy adults. Material and Methods: A total of 22 individuals (11 female, 11 male) participated in the study voluntarily. The experimental group (EG) attended to the breathing exercises for 15 minutes per day, three days a week for six weeks. Neither the EG nor the control group (CG) did join in any regular physical activity program during the study. Both groups participated in the HRV measurements before and after the six-week of process. Results: Only the EG showed statistically significant changes in some HRV parameters. The alterations observed in LF:HF ratio, HFnu, and LFnu parameters were to reflect the increase in parasympathetic activity. Although the changes in the other parameters of HRV such as SDNN, SDSD, RMSSD, TP, HF, LF, and VLF were also related to increased vagal activity, these alterations were not significant. However, no significant change was found in the CG. Conclusions: These results show that only the slow, controlled breathing exercises for six weeks could be used to improve parasympathetic activity in physically active individuals. A study could be designed where the duration is kept over 8 weeks, and the effects of physical exercises only, breathing exercises only, and physical + breathing exercises together on HRV are examined.
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- 2021
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6. Manipulator Detection in Cryptocurrency Markets Based on Forecasting Anomalies
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Firat Akba, Ihsan Tolga Medeni, Mehmet Serdar Guzel, and Iman Askerzade
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Anomaly detection ,cryptocurrency markets ,manipulator detection ,machine learning ,deep learning ,time series analysis ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
Today, there are constant changes in terms of securities in stock markets. In these stock market investments, investors use fundamental analysis tools and indicators very widely. In this way, it is possible to have some knowledge of the situations experienced in the markets and to make a profit. In this study, manipulations on Bitcoin are discussed. Popular machine and statistical forecasting methods have been used to detect these manipulations and the road maps to be followed in order to be detected in the most successful way have been shared. Social media sentiments, which were thought to have an effect on manipulations during the studies, were also evaluated with the most advanced text analysis methods and evaluated together with these price changes. The allegations that the prediction methods carried out before the crisis were more successful were investigated. The Covid-19 pandemic was evaluated as a period of global crisis and the studies that might be relevant were examined. It would not be wrong to say that the actors that make big gains in the stock markets are the ones that determine the direction of the stock market. The manipulation periods of the market actors to be successful in the virtual money markets have been tried to be verified by various estimation methods. These estimations can achieve up to F1 score of 93% success according to our experimental result. Besides, it is stated that accounts with the highest volume of transactions in the periods, when anomalies were detected, were labeled as potential manipulators.
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- 2021
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7. Four-week of local electromyostimulaiton training on fingerboard increases the isokinetic wrist strength and endurance
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Dicle Aras, Selçuk Gül, Fırat Akça, Mehmet Gülü, Özkan Güler, Cemil C. Bıldırcın, Erşan Arslan, and Güney Çetinkaya
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electrical contraction ,isokinetic forearm endurance ,isokinetic forearm strength ,sport climbing ,fingerboard ,Special aspects of education ,LC8-6691 - Abstract
Background and Study Aim: Electromyostimulaiton (EMS) has been used for both physical therapy and strength improvements for a few decades. This study aimed to investigate the effects of a four-week local-EMS training performed on a fingerboard (FT) in wrist strength and endurance. Material and Methods: Sixteen physically active, non-climber students were divided into EMS+FT and FT groups. Each group performed the same training program about 25 min a day, 3 days a week for four weeks. The EMS+FT implementation was performed with a signal width of 260 ms and a frequency of 60 Hz. Before and after training, isokinetic measurements were collected. The parameters used in the research during flexion and extension at 60 and 180°/sec were; Peak Torque (PT), Peak Torque/Body Weight (PT/BW), and Average Power (AP). Results: The EMS+FT group showed statistically significant alterations in all of the parameters (p
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- 2020
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8. Effect Of Intermittent Hypoxia On Cardiac Muscle Calcium Homeostasis In Experimental Type 1 Diabetes Mellitus
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Ayhan Tanyeli, Hakan Fıçıcılar, Fırat Akat, Ali Doğan Dursun, Derya Güzel Erdoğan, and Metin Baştuğ
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diabetic cardiomyopathy ,diabetik kardiyomyopati ,aralıklı hipoksi ,Medicine - Abstract
Purpose: In this study; it was investigated the effect of intermittent hypoxia on cardiac phospholamban and CaMKII levels in experimental diabetic cardiomyopathy. Material and method:Wistar albino male rats (n=34) were randomized to four groups: control (C), intermittent hypoxia (IH), diabetes mellitus (DM) and diabetes mellitus + intermittent hypoxia (DM+IH). Injection of streptozotocin (50 mg/kg, i.p.) followed by 250 mg/dL and above blood glucose levels , was accepted as diabetes mellitus. The IH and DM+IH groups were subjected to 6 hours/day hypoxia for 42 days at a pressure corresponding to a height of 3000 m. 24 hours after the IH protocol was completed, the hearts of the animals were removed. Phospholamban and CaMKII were conducted by agarose gel electrophoresis method after polymerase chain reaction. After the images were obtained with a UV camera; band density was determined in the Image J program. The resulting data were compared with the Kruskal Wallis test, multiple comparisons tests, and the Wilcoxon test. Results:When the rates of the increasing weight of the experimental animals were examined, it was observed that the weight increase in the IH group was at most and the DM group was at least. The differences between C and DM (p=0.003), C to DM+IH (p=0.024), IH to DM (p=0.001), IH to DM+IH (p=0.006) groups were statistically meaningful at the end of the experiment. It has not been detected any meaningful difference among the groups of PLB/GAPDH (p=0.294). In terms of CaMKII/GAPDH, a statistically significant difference was found between C and DM; C and DM+IH and IH and DM+IH groups (p lt;0.05). Conclusion:Our study suggests that CaMKII has a role in diabetic cardiomyopathy in detecting differences in CaMKII level. However, changes in the phospholamban have not been detected, but are important in the effects of translational and/or posttranslational levels and in the changes that may occur in protein levels and/or activations.
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- 2019
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9. Tadalafil versus alpha blockers (alfuzosin, doxazosin, tamsulosin and silodosin) as medical expulsive therapy for < 10 mm distal and proximal ureteral stones
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Serdar Çelik, Firat Akdeniz, Muge Afsar Yildirim, Ozan Bozkurt, Merve Gursoy Bulut, Mehmet Levent Hacihasanoglu, and Omer Demir
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Alpha blockers ,Medical expulsive theraphy ,tadalafil ,Ureteral stone ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Objectives: To evaluate the effect of tadalafil compared with four alpha blockers (alfuzosin, doxazosin, tamsulosin and silodosin) as medical expulsive treatment for ureteral stones in male adults. Materials and methods: Male adults who were admitted to urology clinic with flank pain and diagnosed with non complicated < 10 mm ureteral stone on non-contrast computed tomography (NCCT) between June 2014-September 2015 were retrospectively evaluated. A total of 273 patients with ureteral stone were divided into five groups. Alfuzosin 10 mg/daily, doxazosin 8 mg/daily, tamsulosin 0.4 mg/daily, silodosin 8 mg/daily and tadalafil 5 mg/daily for 6 weeks were prescribed respectively. Stone localization, diameter, volume and Hounsfield units were noted as NCCT findings. The patients were divided into the two groups based on their stone localization as distal and mid-proximal stones. These two groups were evaluated separately. Expulsion rate were noted at the end of 6 weeks. NCCT and treatment findings were compared between five drug groups in distal and mid-proximal stones separately. Results: Age was higher in tadalafil group in distal stones (p = 0.032). Expulsion rate was found 78.1% for alfuzosin, 75.7% for doxazosin, 76.5% for tamsulosin, 88.6% for silodosin and 90% for tadalafil in distal (p = 0.44) and 21.7%, 30%, 30%, 30% and 54.5% in mid-proximal stones (p = 0.034) respectively. Conclusions: Expulsion rate was higher in silodosin and tadalafil for distal ureteral stones but the difference didn’t meet statistical significance. However the expulsion rate was significantly higher in tadalafil than in the other groups for mid-proximal ureteral stones. The result of this study showed that tadalafil may increases ureteric stone expulsion.
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- 2018
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10. The Effects of Exercise Order on the Psychophysiological Responses, Physical and Technical Performances of Young Soccer Players: Combined Small-Sided Games and High-Intensity Interval Training
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Ersan Arslan, Bulent Kilit, Filipe Manuel Clemente, Yusuf Soylu, Mustafa Sögüt, Georgian Badicu, Firat Akca, Mine Gokkaya, and Eugenia Murawska-Ciałowicz
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soccer ,high-intensity ,small-sided games ,psychophysiological responses ,combined training ,Biology (General) ,QH301-705.5 - Abstract
This study aimed to compare the order effects of combined small-sided games (SSGs) and high-intensity interval training (HIIT) on the psychophysiological responses and physical and technical performances of young soccer players. Twenty-four soccer players (aged 14.63 ± 0.71 years) were randomly divided into SSGs + HIIT (n = 12) and HIIT + SSGs (n = 12) for 6 weeks. The SSGs consisted of two 4–16 min rounds of 2, 3, and four-a-side games with 2 min of passive resting, whereas the HIIT consisted of 6–10 min of high-intensity runs at varying intensities (from 90 to 100%). Pre-test and post-test elements included a 5–30 m sprint test, countermovement jump test, zigzag agility test with the ball and without the ball, repeated sprint ability test, speed dribbling ability test, three-corner run test, and Yo-Yo Intermittent Recovery Test level 1. Both combined training interventions produced similar improvements in physical performance and technical responses (p ≥ 0.05, d values ranging from 0.40 to 1.10). However, the combined HIIT + SSGs training produced meaningfully lower perceived exertion (p = 0.00, d = 2.98) and greater physical enjoyment (p = 0.00, d = 4.28) compared with the SSGs + HIIT intervention. Furthermore, the SSGs + HIIT group showed a higher training load than those from the HIIT + SSGs group for all weeks (p ≤ 0.05, d values ranging from 1.36 to 2.05). The present study’s results might be used by coaches and practitioners to design training programmes for youth soccer players.
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- 2021
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11. Increased membrane turnover in the brain in cutaneous anthrax without central nervous system disorder: a magnetic resonance spectroscopy study.
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Bayindir Y, Firat AK, Kayabas U, Alkan A, Yetkin F, Karakas HM, and Yologlu S
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- 2012
12. Magnetic resonance spectroscopic characteristics of glutaric aciduria type II.
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Firat AK, Karakas HM, and Yakinci C
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Magnetic resonance spectroscopy (MRS) of a 12-year-old female patient with glutaric aciduria type II was compared with data obtained from four healthy age- and sex-matched volunteers. In the clinically active phase, conventional magnetic resonance imaging showed mild ventricular dilatation. Frontal lobe choline/creatine (Cho/Cr) ratio (1.98) was higher than the ratios reported for the comparison participants (1.64 [SD 0.21]). The N-acetylaspartate/creatine (NAA/Cr) ratio (1.95) was lower than normal limits (2.66 [SD 0.23]). After successful riboflavin treatment and dietary restriction for proteins, the NAA/Cr ratio was within the normal range (2.44) and Cho/Cr ratio was below the normal range (1.15), suggesting riboflavin-responsive multiple acyl-coA dehydrogenase deficiency. An elevated Cho/Cr ratio and decreased NAA/Cr ratio is consistent with a demyelinating process in the active phase of glutaric aciduria type II. MRS helps to monitor the progress of the disease and the efficacy of treatment by revealing changes in NAA/Cr and Cho/Cr ratios. [ABSTRACT FROM AUTHOR]
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- 2006
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13. Unilateral reverse ocular bobbing caused by tuberous sclerosis.
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Karakas HM, Yakinci C, Firat AK, and Kahraman B
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A female aged 12 months with developmental delay and left-sided reverse ocular bobbing (rapid deviation of the eye upward and a slow return to the horizontal position) was observed. At birth, an upper left gingival mass, pathologically diagnosed as a benign granular cell tumour, was removed. On computed tomography (CT), left middle cerebral pedincular and midpontine lesions were seen. Magnetic resonance imaging revealed additional white matter hamartomas, corticosubcortical tubers, and subependymal nodules. The patient was re-examined at 36 months. Her general developmental quotient was equivalent to 23 months of age. Third cranial nerve functions and auditory brainstem response were normal. Her abnormal eye movements were still present. Reverse bobbing is usually observed in patients who are unconscious and who have significant pontine pathology and disruption of the reticular formation. This case is the first tuberous sclerosis-related ocular bobbing case to our knowledge and is interesting as the causative lesion was relatively mild, and ocular horizontal movements were preserved. [ABSTRACT FROM AUTHOR]
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- 2006
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14. Effect of nasal septal deviation on total ethmoid cell volume.
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Firat AK, Miman MC, Firat Y, Karakas M, Ozturan O, and Altinok T
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BACKGROUND: The aim of this study was to evaluate the effect of nasal septal deviation (NSD) on ethmoid cell volume and to determine whether there was any correlation between NSD grade and ethmoid cell volume. METHODS: Forty computerized tomography (CT) scans from patients with rhinosinusitis symptoms with NSD were evaluated. Septal deviations were classified into three groups according to the degree of deviation on CT. Ethmoid cell volumes were measured and the relationship between NSD and ethmoid cell volume was investigated. RESULTS: There was a moderate but significant negative correlation between the septal deviation angle and the percentage of the ethmoid cell volumes (p = 0.001, r = -0.5152, r2 = 0.2654). Total ethmoid cell volume on the ipsilateral side compared with the contralateral side was found to decrease as the degree of NSD increased. CONCLUSIONS: Nasal septal deviation affects the total ethmoid cell volume of the nasal cavity. The results of our study underline the role of ethmoid cell volume in the compensation mechanism equalizing the nasal cavity airflow changes due to NSD. [ABSTRACT FROM AUTHOR]
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- 2006
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15. Computed tomography findings predicting the success of silodosin for medical expulsive therapy of ureteral stones
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Serdar Celik, Firat Akdeniz, Muge Afsar Yildirim, Ozan Bozkurt, Merve Gursoy Bulut, Mehmet Levent Hacihasanoglu, and Omer Demir
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Hounsfield units (HU) ,Medical expulsive therapy (MET) ,Non-contrast computed tomography (NCCT) ,Proximal ureteral stone ,Ureteral stone ,Medicine (General) ,R5-920 - Abstract
Aim of the study is to investigate the relationship between non-contrast computed tomography (NCCT) findings and stone expulsion rate with medical expulsive therapy (MET) using silodosin for ureteral stones in male adults. Between January 2014 and June 2015, we retrospectively reviewed the patient charts with uncomplicated ureteral stones on NCCT images, who were treated with silodosin for MET. Stone diameter, volume and hounsfield units (HU) measured by NCCT and treatment findings were noted at the end of treatment. Patients were divided into three groups according to the localization as distal, mid and proximal ureteral stones. NCCT and treatment findings were compared between MET success and failure groups in different localizations. Stone expulsion rate was 81.3% for 134 distal, 45.5% for 22 mid and 27.7% for 47 proximal stones. Stone diameter, volume, and HU were significantly lower for success groups with distal and proximal stones (p
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- 2017
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16. Epoxyeicosatrienoic Acid-Based Therapy Attenuates the Progression of Postischemic Heart Failure in Normotensive Sprague-Dawley but Not in Hypertensive Ren-2 Transgenic Rats
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Jaroslav Hrdlička, Jan Neckář, František Papoušek, Zuzana Husková, Soňa Kikerlová, Zdenka Vaňourková, Zdenka Vernerová, Firat Akat, Jana Vašinová, Bruce D. Hammock, Sung Hee Hwang, John D. Imig, John R. Falck, Luděk Červenka, and František Kolář
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epoxyeicosatrienoic acid ,soluble epoxide hydrolase ,chronic heart failure ,hypertension ,myocardial infarction ,echocardiography ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Epoxyeicosatrienoic acids (EETs) and their analogs have been identified as potent antihypertensive compounds with cardio- and renoprotective actions. Here, we examined the effect of EET-A, an orally active EET analog, and c-AUCB, an inhibitor of the EETs degrading enzyme soluble epoxide hydrolase, on the progression of post-myocardial infarction (MI) heart failure (HF) in normotensive Hannover Sprague-Dawley (HanSD) and in heterozygous Ren-2 transgenic rats (TGR) with angiotensin II-dependent hypertension. Adult male rats (12 weeks old) were subjected to 60-min left anterior descending (LAD) coronary artery occlusion or sham (non-MI) operation. Animals were treated with EET-A and c-AUCB (10 and 1 mg/kg/day, respectively) in drinking water, given alone or combined for 5 weeks starting 24 h after MI induction. Left ventricle (LV) function and geometry were assessed by echocardiography before MI and during the progression of HF. At the end of the study, LV function was determined by catheterization and tissue samples were collected. Ischemic mortality due to the incidence of sustained ventricular fibrillation was significantly higher in TGR than in HanSD rats (35.4 and 17.7%, respectively). MI-induced HF markedly increased LV end-diastolic pressure (Ped) and reduced fractional shortening (FS) and the peak rate of pressure development [+(dP/dt)max] in untreated HanSD compared to sham (non-MI) group [Ped: 30.5 ± 3.3 vs. 9.7 ± 1.3 mmHg; FS: 11.1 ± 1.0 vs. 40.8 ± 0.5%; +(dP/dt)max: 3890 ± 291 vs. 5947 ± 309 mmHg/s]. EET-A and c-AUCB, given alone, tended to improve LV function parameters in HanSD rats. Their combination amplified the cardioprotective effect of single therapy and reached significant differences compared to untreated HanSD controls [Ped: 19.4 ± 2.2 mmHg; FS: 14.9 ± 1.0%; +(dP/dt)max: 5278 ± 255 mmHg/s]. In TGR, MI resulted in the impairment of LV function like HanSD rats. All treatments reduced the increased level of albuminuria in TGR compared to untreated MI group, but neither single nor combined EET-based therapy improved LV function. Our results indicate that EET-based therapy attenuates the progression of post-MI HF in HanSD, but not in TGR, even though they exhibited renoprotective action in TGR hypertensive rats.
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- 2019
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17. Second primary cancers in patients with urothelial cancers
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Ali Feyzullah Şahin, Muammer Altok, Fırat Akdeniz, Güner Yıldız, and Rauf Taner Divrik
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Multiple primary neoplasms ,Second primary neoplasms ,Urothelial neoplasms ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Purpose: To investigate the second primary cancers (SPCs) in patients with urothelial cancer (UC). Materials and Methods: The records of 2,339 patients whose UC was diagnosed between January 1974 and December 2012 were reviewed. All data about characteristics of patients, of UC and, of SPC was, recorded digitally. We investigated the prevalence and the type of second or higher order cancers, and the factors associated with SPC. Results: Total 260 patients (11.1%) had SPC, 14 had a third primary cancer and one had a fourth primary cancer. The most common SPC with UC was lung cancer (29.6%). Of all 260 with SPC, 64 (24.6%) had synchronous (within the 6 months) SPC, 120 (46.2%) had subsequent SPC and, 76 (29.2%) had antecedent SPC. The mean duration of SPC was 56 months in patients with subsequent SPC and 75.8 months in patients with antecedent SPC. The mean age at the time of diagnosis of UC was higher in patients with SPC. The ratio of male gender, body mass index, blood type, status of smoking and, occupational risk was similar in both groups. Total amount of smoking and the mean follow-up were higher in patients with SPC. Conclusions: The majority of the patients with UC have long life expectancy. In patients with UC, the risk of having another cancer is quite higher than normal population. The physicians managing patients with UC should look for SPC.
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- 2016
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18. The effect of two different strength training programs applied to male athletes in the various branches on some physical and physiological parameters
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Fırat Akcan and Mursel Bıcer
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physical and physiological ,strength ,training ,training. ,Sports medicine ,RC1200-1245 - Abstract
The purpose of this study is to research the physical and physiological effects of male athletes of the 8-week two different strength training programs. Three groups have been constituted from the volunteers among 18-30 ages who have participated in the study; Explosive Strength Group (ESG, n=12), Strength Endurance Group (SEG, n=12) and Control Group (CG, n=12). Explosive Strength and strength endurance training programs have been applied to ESG and SEG 8-week and 3 days in a week respectively.CG hasn’t been included in any training program. Height, body weight, back, leg and hand grip strength, flexibility, vertical jump, body fat percentage, 20m and 30m sprint and 20m shuttle run tests have been applied to the volunteers. Paired Samples T Test has been applied to the pre-test post-test measurements of the groups. One Way ANOVA Test and Tukey HSD test; besides Kruskal Wallis test and Dunnett’s T3 test have been used among the groups. Among the pretest post-tests of the groups ; heights, body fat percentage , relative and absolute back, leg and hand grip strengths, 20m and 30 m sprint, vertical jump, flexibility and at value of MaxVO2 at p lt;0.05 level significance has been determined. In Anaerobic strength values, in ESG and CG groups, significance at the level of p lt;0.05 has been determined. In the differences among the groups; heights, body fat percentage, absolute and relative back strength, relative right and left hand grip strengths, in 20m sprint and vertical jump values, significance has been determined at the level of p lt;0.05 when CG is compared among the groups, in the favour of ESG and SEG, when ESG and CG are compared about leg strength values, in the favour of ESG, when SEG and CG are compared about flexibility, in the favour of SEG. Significance hasn’t been determined between ESG and SEG groups. As a result, it can be said that there are positive effects of the Explosive Strength and strength endurance trainings on some physical and physiological parameters
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- 2015
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19. Comparative analysis of the 1-mile run test evaluation formulae: Assessment of aerobic capacity in male law enforcement officers aged 20–23 years
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Gürhan Kayihan, Ali Özkan, Yusuf Köklü, Ender Eyuboğlu, Firat Akça, Mitat Koz, and Gülfem Ersöz
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Maximal oxygen uptake ,field aerobic tests ,police officers ,one mile run test ,physical fitness ,young adults ,Medicine - Abstract
Objectives: The purpose of this study was to compare values of aerobic performance in the 1-mile run test (1-MRT) using different formulae. Material and Methods: Aerobic capacities of 351 male volunteers working for the Turkish National Police within the age range of 20-23 years were evaluated by the 1-MRT and the 20-metre shuttle run (20-MST). VO2max values were estimated by the prediction equations developed by George et al. (1993), Cureton et al. (1995) and Kline et al. (1987) for the 1-MRT and by Leger and Lambert (1982) for the 20-MST. Results: The difference between the results of the different formulae was significant (p = 0.000). The correlation coefficient between the estimated VO2max using Cureton's equation, George's equation, Kline's equation and the 20-MST were 0.691 (p < 0.001), 0.486 (p < 0.001) and 0.608 (p < 0.001), respectively. The highest correlation coefficient was between the VO2max estimated by the 20-MST and Cureton's equation. Similarly, the highest correlation coefficient (r = -0.779) was between the 1-mile run time and the VO2max estimated by Cureton's equation. Conclusions: When analysing more vigorous exercise than sub-maximal exercise, we suggest that Cureton's equation be used to predict the VO2max from 1-mile run/walk performance in large numbers of healthy individuals with high VO2max. This research compares the use of 3 different formulae to estimate VO2max from 1-mile run/ walk performance in male law enforcement officers aged 20-23 years for the first time and reports the most accurate formula to use when evaluating aerobic capacities of large numbers of healthy individuals.
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- 2014
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20. Unusual symptom of intestinal malrotation: episodic cervical dystonia due to Sandifer syndrome.
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Firat AK, Karakas HM, Firat Y, and Yakinci C
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- 2007
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21. Corrigendum to 'Computed tomography findings predicting the success of silodosin for medical expulsive therapy of ureteral stones' [Kaohsiung J Med Sci 33 (6) (2017) 290–294]
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Serdar Celik, Firat Akdeniz, Muge Afsar Yildirim, Ozan Bozkurt, Merve Gursoy Bulut, Mehmet Levent Hacihasanoglu, and Omer Demir
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Medicine (General) ,R5-920 - Published
- 2018
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22. Dev sinüs Valsalva anevrizmasi.
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Karakas HM, Kahraman B, Sagir A, Firat AK, Karakaş, Hakki Muammer, Kahraman, Bayram, Sağir, Ayşegül, and Firat, Ahmet Kemal
- Published
- 2006
23. A heart transplant recipient lost due to Pneumocystis jiroveci pneumonia under trimethoprim-sulfamethoxazole prophylaxis: case report.
- Author
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Celik T, Gedik E, Kayabas U, Bayindir Y, Gulbas G, Firat AK, and Togal T
- Subjects
- Fatal Outcome, Female, Humans, Immunosuppressive Agents adverse effects, Pneumonia, Pneumocystis diagnostic imaging, Pneumonia, Pneumocystis microbiology, Time Factors, Tomography, X-Ray Computed, Treatment Failure, Young Adult, Anti-Infective Agents administration & dosage, Antibiotic Prophylaxis, Heart Transplantation adverse effects, Pneumocystis carinii pathogenicity, Pneumonia, Pneumocystis drug therapy, Trimethoprim, Sulfamethoxazole Drug Combination administration & dosage
- Abstract
Infections in solid-organ transplant recipients are the most important causes of morbidity and mortality. A primary goal in organ transplant is the prevention or effective treatment of infection, which is the most common life-threatening complication of long-term immunosuppressive therapy. A 21-year-old woman who underwent heart transplant 3 years previous owing to dilated cardiomyopathy was referred to our hospital with symptoms of high fever and cough. The patient's history revealed that she had received a trimethoprim-sulfamethoxazole double-strength tablet each day for prophylactic purposes. On chest radiograph, pneumonia was detected, and in broncho-alveolar lavage sample, Pneumocystis jiroveci cysts were found. After diagnosing P. jiroveci pneumonia, trimethoprim-sulfamethoxazole was initiated at 20 mg/kg/d including intravenous trimethoprim in divided dosages every 6 hours. On the sixth day of therapy, she died in intensive care unit. In solid-organ transplant recipients, although antipneumocystis prophylaxis is recommended within the first 6 to 12 months after transplant, lifelong prophylaxis is also used in several settings. In addition, the physician should keep in mind that P. jiroveci pneumonia may develop in solid organ recipients, despite trimethoprim-sulfamethoxazole prophylaxis.
- Published
- 2010
24. Diffusion-weighted images differentiate benign from malignant thyroid nodules.
- Author
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Erdem G, Erdem T, Muammer H, Mutlu DY, Firat AK, Sahin I, and Alkan A
- Subjects
- Adult, Aged, Diagnosis, Differential, Female, Humans, Image Enhancement methods, Male, Middle Aged, Reproducibility of Results, Sensitivity and Specificity, Algorithms, Diffusion Magnetic Resonance Imaging methods, Image Interpretation, Computer-Assisted methods
- Abstract
Purpose: To reveal the possible role of diffusion-weighted images (DWI) in the differential diagnosis of benign and malignant thyroid nodules by comparing the results of fine-needle aspiration cytology (FNAC)., Materials and Methods: In an 18-month period (December 2005 to May 2007), 27 cases with benign thyroid nodules with a total of 52 benign nodules, nine cases with thyroid gland malignancy, and 24 healthy control cases were included in the study. Cases that were indicated to undergo to FNAC examination and sent by a clinician for biopsy to the radiology unit were included in the study to assess the cytopathologic confirmation of the clinic, ultrasonographic, and magnetic resonance imaging (MRI) findings., Results: The mean apparent diffusion coefficient (ADC) values of thyroid nodules were 2745.3 +/- 601.1 x 10(-6) mm(2)/s (1605-3899 x 10(-6)mm(2)/s) in the benign group and 695.2 +/- 312.5 x 10(-6)mm(2)/s (165-1330 x 10(-6)mm(2)/s) in the malignant group. Normal thyroid tissues had mean ADC values of 1344.1 +/- 276.4 x 10(-6) mm(2)/s (1015-1764 x 10(-6)mm(2)/s). The ADC values of three subgroups were significantly different (P = 0.0001). A reduced ADC was observed in most types of malignant tumors due to the consequent decrease of the extracellular extravascular space., Conclusion: Our preliminary results showed that ADC values of nodules may provide useful data about the nature of a thyroid nodule., ((c) 2009 Wiley-Liss, Inc.)
- Published
- 2010
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25. Incontinentia pigmenti: a case report and literature review.
- Author
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Emre S, Firat Y, Güngör S, Firat AK, and Karincaoğlu Y
- Subjects
- Female, Humans, Infant, Magnetic Resonance Imaging, Ultrasonography, Incontinentia Pigmenti diagnosis
- Abstract
Incontinentia pigmenti (IP) is a rare, X-linked dominant disorder that presents at or soon after birth with characteristic cutaneous signs. The eyes and central nervous system are the next most commonly affected systems. We aimed to describe the ophthalmological, neurological and radiodiagnostic findings of a patient with IP and bilateral retinal detachment. Clinical and laboratory findings of a four-month-old female baby who did not have light fixation and had neurological maturation retardation are presented. Characteristic skin lesions of IP were noted especially at the extremities, bilaterally. On neurological examination, motor and mental maturation were retarded and axial hypotonia was noted. Bilateral retinal detachment was the cause of absent eye fixation noted during ophthalmologic examination, and the detachments were also documented by ultrasonography and magnetic resonance imaging (MRI). Otologic examination was normal. Focal left frontal lobe atrophy, corpus callosum hypoplasia and prominence of right hemisphere were also noted on MRI. MR spectroscopy revealed negative lactate peak at the involved left frontal lobe. Bilateral retinal detachment is a probable finding in IP and patients with neurological symptoms should be investigated for associated sight-threatening ocular pathologies.
- Published
- 2009
26. Microstructural changes in uterine leiomyomas and myometrium: a diffusion-weighted magnetic resonance imaging study.
- Author
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Erdem G, Celik O, Karakas HM, Hascalik S, and Firat AK
- Subjects
- Adult, Aged, Female, Humans, Leiomyoma diagnosis, Middle Aged, ROC Curve, Sensitivity and Specificity, Uterine Neoplasms diagnosis, Diffusion Magnetic Resonance Imaging, Leiomyoma pathology, Myometrium pathology, Uterine Neoplasms pathology
- Abstract
Although morphological and histopathological changes in uterine leiomyomas have been investigated in detail, the microstructural disruptions could not be studied in the living organism. Diffusion-weighted magnetic resonance imaging (DWI) is a novel tool to assess microstructural changes in vivo. The aim of this study was to investigate and characterize the diffusional property of leiomyomatous tissues with DWI. Sixteen females with a total of 21 leiomyomas were imaged with a 1.5-tesla clinical MR scanner. DWI images of leiomyomas, adjacent myometrial and myometrial tissues of healthy controls were obtained and quantified using apparent diffusion coefficient (ADC) maps. Mean ADC values of these groups were 1,201, 1,684, 1,661 mm(2)/s x 10(-6), respectively. ADC values in leiomyomas were significantly lower than those observed in the myometrium (p < 0.001). Cut-off values produced 91% sensitivity and 100% specificity. As ADC values implied the presence of cytotoxic edema in leiomyomas, the technique was found to be promising in observing temporal variations in leiomyomas and to monitor even the most subtle effects of therapeutic interventions., (Copyright (c) 2009 S. Karger AG, Basel.)
- Published
- 2009
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27. Neuroimaging findings in hyperargininemia.
- Author
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Güngör S, Akinci A, Firat AK, Tabel Y, and Alkan A
- Subjects
- Arginine metabolism, Aspartic Acid analogs & derivatives, Aspartic Acid metabolism, Atrophy, Basal Ganglia Cerebrovascular Disease diagnosis, Basal Ganglia Cerebrovascular Disease genetics, Cerebellum pathology, Cerebral Cortex pathology, Child, Preschool, Choline metabolism, Consanguinity, Creatine metabolism, Dominance, Cerebral physiology, Humans, Intellectual Disability diagnosis, Intellectual Disability genetics, Male, Putamen pathology, Brain Diseases diagnosis, Energy Metabolism physiology, Hyperargininemia diagnosis, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Magnetic Resonance Spectroscopy, Nerve Fibers, Myelinated pathology
- Abstract
In hyperarginenemia, there is a defect in argininase enzyme, which is a catalyzer of urea cycle. Though the pathogenesis of neuronal damage in hyperargininemia is not clear, high serum and cerebrospinal fluid arginine levels can be directly related with neuronal damage. In this study, our aim was to assess brain magnetic resonance images and magnetic resonance spectroscopy (MRS) patterns of two siblings with hyperarginenemia. We acquired single voxel MRS from the white matter to show the myelination pattern and to figure out any abnormal peak of metabolite stored due to enzymatic defect. We observed mild cerebral and cerebellar atrophy and infarct at bilateral posterior putamen and insular cortex localization on conventional images and elevated choline/creatine ratios and abnormal peak at 3.8 ppm, most likely representing arginine deposition. To the best of our knowledge, this is the first article revealing the brain MRS pattern of hyperargininemia. We reported the clinical and imaging findings of patients and discuss the correlation.
- Published
- 2008
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28. Isolated preauricular pits and tags: is it necessary to investigate renal abnormalities and hearing impairment?
- Author
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Firat Y, Sireci S, Yakinci C, Akarçay M, Karakaş HM, Firat AK, Kizilay A, and Selimoğlu E
- Subjects
- Adolescent, Case-Control Studies, Child, Female, Hearing Disorders diagnosis, Hearing Disorders epidemiology, Humans, Incidence, Kidney Diseases diagnosis, Kidney Diseases epidemiology, Male, Otoacoustic Emissions, Spontaneous, Otoscopy, Prevalence, Risk Factors, Urinalysis, Ear, External abnormalities, Hearing Disorders congenital, Kidney abnormalities, Kidney Diseases congenital
- Abstract
We investigated the incidence and co-existence of hearing impairment and renal abnormalities in healthy children with preauricular tags and pits. Study population consists of 13,740 primary school children from routine health check. Thirty-five children with preauricular tags and pits were noted. Control group consisted of 91 patients without pits and tags, who underwent renal ultrasound and were scheduled to pediatric outpatient clinic. Urinalysis, renal ultrasound, otoacoustic emission were performed in both the groups. The prevalence of renal abnormality (1/36; 2.7%) and hearing impairment (1/36; 2.7%) in patients with preauricular tags and pits was similar to that of control group (3/91; 3.2% and 4/91; 4.3%) (P = 0.87, P = 0.64, respectively). According to our results, it is not necessary to investigate hearing or urinary abnormality in patients with preauricular tag or pit, unless there is an association of a syndrome or family history of hearing or renal impairment.
- Published
- 2008
- Full Text
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29. Evaluation of in vivo cerebral metabolism on proton magnetic resonance spectroscopy in patients with impaired glucose tolerance and type 2 diabetes mellitus.
- Author
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Sahin I, Alkan A, Keskin L, Cikim A, Karakas HM, Firat AK, and Sigirci A
- Subjects
- Adult, Aged, Aspartic Acid analogs & derivatives, Aspartic Acid metabolism, Choline metabolism, Creatine metabolism, Female, Glucose Tolerance Test, Humans, Inositol metabolism, Magnetic Resonance Imaging, Male, Middle Aged, Cerebral Cortex metabolism, Diabetes Mellitus, Type 2 metabolism, Glucose Intolerance metabolism
- Abstract
The aim of this study was to investigate possible metabolic alterations in cerebral tissues on magnetic resonance spectroscopy (MRS) in patients with impaired glucose tolerance (IGT) and with type 2 diabetes mellitus (T2-DM). Twenty-five patients with T2-DM, 13 patients with IGT, and 14 healthy volunteers were included. Single-voxel spectroscopy (TR: 2000 ms, TE: 31 ms) was performed in all subjects. Voxels were placed in the frontal cortex, thalamus, and parietal white matter. N-acetylaspartate (NAA)/creatine (Cr), choline (Cho)/Cr, and myo-inositol (MI)/Cr ratios were calculated. Frontal cortical Cho/Cr ratios were increased in patients with IGT compared to control subjects. Parietal white matter Cho/Cr ratios were significantly higher in patients with IGT when compared to patients with T2-DM. In the diabetic group, frontal cortical MI/Cr ratios were increased, and parietal white matter Cho/Cr ratios were decreased when compared to the control group. Frontal cortical NAA/Cr and Cho/Cr ratios and parietal white matter Cho/Cr ratios were decreased in diabetic patients with poor glycemic control (A1C>10%). A1C levels were inversely correlated with frontal cortical NAA/Cr and Cho/Cr ratios and with parietal white matter Cho/Cr ratios. T2-DM and IGT may cause subtle cerebral metabolic changes, and these changes may be shown with MRS. Increased Cho/Cr ratios may suggest dynamic change in membrane turnover in patients with IGT. Diabetic patients with poor glycemic control may be associated with neuronal dysfunction/damage in brain in accordance with A1C levels and, in some, extend with insulin resistance.
- Published
- 2008
- Full Text
- View/download PDF
30. Magnetic resonance spectroscopy features of normal-appearing white matter in patients with acute brucellosis.
- Author
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Kayabas U, Alkan A, Firat AK, Karakas HM, Bayindir Y, and Yetkin F
- Subjects
- Acute Disease, Adolescent, Adult, Aspartic Acid analogs & derivatives, Aspartic Acid metabolism, Brain Diseases metabolism, Brucellosis metabolism, Case-Control Studies, Choline metabolism, Contrast Media, Creatine metabolism, Female, Gadolinium DTPA, Humans, Male, Middle Aged, Statistics, Nonparametric, Brain Diseases diagnosis, Brain Diseases microbiology, Brucellosis pathology, Magnetic Resonance Spectroscopy methods
- Abstract
We aimed to evaluate whether the subtle metabolic cerebral changes are present in normal-appearing white matter on conventional MRI, in patients with acute brucellosis, by using MR spectroscopy (MRS). Sixteen patients with acute brucellosis and 13 healthy control subjects were investigated with conventional MRI and single-voxel MRS. Voxels were placed in normal-appearing parietal white matter (NAPWM). N-Acetyl aspartate (NAA)/creatine (Cr) and choline (Cho)/Cr ratios were calculated. There was no significant difference between the study subjects and the control group in NAA/Cr ratios obtained from NAPWM. However, the Cho/Cr ratios were significantly higher in patients with acute brucellosis compared to controls (p=0.01). MRS revealed metabolic changes in normal-appearing white matter of patients with brucellosis. Brucellosis may cause subtle cerebral alterations, which may only be discernible with MRS. Increased Cho/Cr ratio possibly represents an initial phase of inflammation and/or demyelination process of brucellosis.
- Published
- 2008
- Full Text
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31. 1H magnetic resonance spectroscopy of the normal testis: preliminary findings.
- Author
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Firat AK, Uğraş M, Karakaş HM, Erdem G, Kurus M, Ugras M, Celik T, Kahraman B, and Doğanay S
- Subjects
- Adolescent, Adult, Child, Choline metabolism, Humans, Image Processing, Computer-Assisted, Lipid Metabolism, Male, Reference Values, Statistics, Nonparametric, Magnetic Resonance Spectroscopy methods, Testis metabolism
- Abstract
Purpose: The purpose of this study was to determine the pre- and postpubertal 1H magnetic resonance spectroscopic characteristics of the normal testis to establish baseline values for further clinical studies., Materials and Methods: The subjects consisted of male volunteers, of whom 19 were prepubertal with ages between 7 and 13 years and 24 were postpubertal with ages between 19 and 39 years. Their testes were evaluated at 1.5 T with magnetic resonance spectroscopy; in addition, testis volumes were measured. Major metabolite peaks were identified and their ratios were calculated. Metabolite differences of testis between pre- and postpubertal age were analyzed., Results: Major constituents of spectra were 3.21 ppm choline and 0.9-1.3 ppm lipid peaks. At the echo time (TE) spectrum of 31 ms, choline/lipid ratios ranged from 0.35 to 8.30 (mean=1.87) in postpubertal males and from 0.06 to 5.45 (mean=0.88) in prepubertal males (P<.013). At the TE spectrum of 136 ms, choline/lipid ratios ranged from 0.66 to 15.42 (mean=4.09) in postpubertal males and from 0.05 to 4.91 (mean=0.9) in prepubertal males (P<.016)., Conclusions: Choline/lipid ratio was higher in the postpubertal period. The existence of higher choline peak in that age group should be due to the initiation of spermatogenesis. The decrease in the lipid peak may represent the effect of testosterone on testicular tissue or may be due to histochemical changes initiated by puberty. The significant decrease in choline/lipid ratio noted after puberty could represent the presence of spermatogenesis. This hypothesis should be evaluated by further studies on postpubertal subjects with impaired spermatogenesis.
- Published
- 2008
- Full Text
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32. Magnetic resonance imaging of muscular involvement in juvenile dermatomyositis: case report.
- Author
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Alicioglu B, Karakas HM, and Firat AK
- Subjects
- Child, Preschool, Humans, Lower Extremity, Male, Skin pathology, Dermatomyositis pathology, Diffusion Magnetic Resonance Imaging, Muscle, Skeletal pathology
- Abstract
A case of 5 year old juvenile patient with dermatomyositis together with conventional and diffusion-weighted MRI images is reported. The reported case was atypical for the pattern of involvement of the accompanying oedema which was affecting distal parts of the extremities and anterior muscle groups. Electromyography was negative. The case confirmed by a pathologist demonstrates the use of diffusion weighted imaging in determining unequivocal oedema and its exact extent.
- Published
- 2008
33. Ciprofloxacin-induced urticaria and tenosynovitis: a case report.
- Author
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Kayabas U, Yetkin F, Firat AK, Ozcan H, and Bayindir Y
- Subjects
- Adult, Female, Humans, Magnetic Resonance Imaging, Tenosynovitis pathology, Urticaria pathology, Ciprofloxacin adverse effects, Tenosynovitis chemically induced, Urticaria chemically induced
- Abstract
Background: Tendon disorders are rare events associated with fluoroquinolone congestion. Skin reactions are more frequent than tendon disorders. We reported this case as the combination of ciprofloxacin-induced urticaria and tenosynovitis has been unreported in young women., Case: A 28-year-old woman without underlying disease developed urticarias and tendinopathy 4 days after the initiation of ciprofloxacin treatment for urinary infection. MRI of the left foot revealed increased synovial fluid surrounding the tendon of the flexor hallucis longus muscle representing tenosynovitis. Ciprofloxacin was ceased due to the possibility of ciprofloxacin-induced tendinopathy and urticaria. Complete resolution of her symptoms and findings occurred 3 days after discontinuation of ciprofloxacin without any additional treatment., Conclusion: Early discontinuation of fluoroquinolone therapy when tendinopathy is suspected is the basis of therapy. So, it should be kept in mind that fluoroquinolone-induced tendinopathy may occur in an otherwise healthy young patient with no risk factors and in a site other than the Achilles tendon., ((c) 2008 S. Karger AG, Basel.)
- Published
- 2008
- Full Text
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34. Diffusion-weighted imaging evaluation of subtle cerebral microstructural changes in intrauterine fetal hydrocephalus.
- Author
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Erdem G, Celik O, Hascalik S, Karakas HM, Alkan A, and Firat AK
- Subjects
- Humans, Brain pathology, Diffusion Magnetic Resonance Imaging methods, Fetal Diseases pathology, Fetus pathology, Hydrocephalus pathology, Image Enhancement methods, Prenatal Diagnosis methods
- Abstract
Objective: Hydrocephalus is an important etiological factor in neurological decline. With the advent of fetal ultrasound, fetal hydrocephalus is now more frequently detected than in the past. Ultrasonography (USG) provides information on general morphology, but microstructural changes that may play a prognostic role are beyond the resolution of that technique. These changes may theoretically be revealed by diffusion-weighted magnetic resonance imaging (DW-MRI). In this study, our preliminary findings of DW-MRI on the hydrocephalic fetuses are presented., Materials and Methods: Twelve fetuses with fetal USG diagnosis of hydrocephalus were investigated using a 1.5-T MR scanner. In addition to conventional techniques, DWI was performed. It was obtained using a single-shot echo-planar imaging sequence (TR/TE: 4393/81 ms; slice thickness: 5 mm; interslice gap: 1 mm; FOV: 230 mm; matrix size: 128x256; b values: 0 and 1000 s/mm2). Apparent diffusion coefficient (ADC) values were measured in the white matter of the periventricular frontal and occipital lobes, basal ganglia, thalamus, centrum semiovale and cerebrospinal fluid in the lateral ventricle. These values were compared with the normal prenatal ADC values from a radiological study published in the literature., Results: All fetuses had moderate or severe bilateral supratentorial ventricular dilatation that was compatible with hydrocephalus. On conventional T1- and T2-weighted imaging, cerebral parenchyma had normal signal pattern and ADC values were significantly lower than those reported for fetuses with normal brain. These values were lower in hydrocephalic fetuses with statistical significance (P<.05-.01)., Conclusion: DWI is a sensitive technique to investigate cerebral microstructure. The reduction in cerebral blood flow and alterations in cerebral energy metabolism in cases with hydrocephalus have been shown before. Changes in cerebral blood flow and energy metabolism, as a consequence of cerebral compression, may occur in hydrocephalus. Elevated ventricular pressure may cause cerebral ischemia. The anaerobic glycolysis seen in the hydrocephalic brain tissue by increasing the lactate concentration and intracellular fluid flux may be the reason for the reduced ADC values in hydrocephalic fetuses. However, long-term prospective trials on the correlation of ADC values and neurological outcome are necessary to exploit the full benefit of that novel technique.
- Published
- 2007
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35. [Dynamic contrast-enhanced magnetic resonance imaging findings of mass lesions of the pontocerebellar angle].
- Author
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Firat AK, Karakaş HM, Kahraman B, Firat Y, Altinok T, and Kizilay A
- Subjects
- Adolescent, Adult, Aged, Child, Contrast Media, Female, Humans, Male, Meningioma pathology, Middle Aged, Neuroma, Acoustic pathology, Paraganglioma pathology, Predictive Value of Tests, Brain Neoplasms pathology, Cerebellopontine Angle pathology, Magnetic Resonance Imaging
- Abstract
Objectives: The differential diagnosis of mass lesions of the pontocerebellar angle is not always possible by conventional magnetic resonance imaging (MRI). In this study, we investigated the role of dynamic contrast-enhanced MRI in the differential diagnosis of acoustic neurinoma, meningioma, and paraganglioma., Patients and Methods: Twelve patients (8 females, 4 males; mean age 47.5 years; range 8 to 71 years) whose diagnoses were acoustic neurinoma (n=3), paraganglioma (n=5), and meningioma (n=4) were evaluated by simultaneous conventional and dynamic contrast-enhanced MRI. Prior to postcontrast T1-weighted images, dynamic MRI was obtained. On these images, maximum contrast enhancement (Cmax) and time to peak enhancement (Tmax) were calculated at 15 different time points. Time-signal intensity curve patterns of the lesions were compared., Results: According to the four main time-signal intensity curve patterns described in the literature, acoustic neurinomas, meningiomas, and paragangliomas exhibited type C, type A-B, and type A curve patterns, respectively., Conclusion: Our results suggest that dynamic contrast MRI may have an additional but limited role in the differential diagnosis of extra-axial intracranial tumors such as those of the pontocerebellar angle.
- Published
- 2007
36. [Chondroradionecrosis in two patients with laryngeal carcinoma].
- Author
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Firat Y, Kizilay A, Firat AK, Serin M, and Erkal HS
- Subjects
- Aged, Combined Modality Therapy, Diagnosis, Differential, Humans, Laryngeal Neoplasms surgery, Magnetic Resonance Imaging, Male, Middle Aged, Necrosis, Tomography, X-Ray Computed, Laryngeal Neoplasms radiotherapy, Larynx pathology, Radiation Injuries pathology
- Abstract
Postradiotherapy necrosis in the larynx is a rare but serious complication. It must be differentiated from tumor recurrence with radiological and histopathological studies. Herein, we presented two patients with stage II and stage IV larynx carcinoma who developed chondroradionecrosis following radiotherapy. The first patient did not accept surgical treatment and was treated with curative radiotherapy at a dose of 70 Gy. The other one received adjuvant radiotherapy at a dose of 46 Gy following total laryngectomy and bilateral functional neck dissection. The two patients were evaluated with computed tomography and magnetic resonance imaging, respectively. Pathologic examination of multiple biopsies taken from both cases showed coagulation necrosis without malignancy. The first patient had grade IV radionecrosis according to the Chandler classification and underwent total laryngectomy because of non-functional larynx. Histopathologically, there were no malignant cells, but widespread fibrosis and coagulation necrosis. The other patient was treated with conservative treatment and local debridement.
- Published
- 2007
37. A case of frontal lobe abscess as a complication of frontal sinus ossifying fibroma.
- Author
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Firat Y, Firat AK, Karakaş HM, and Onal C
- Subjects
- Follow-Up Studies, Headache etiology, Humans, Male, Middle Aged, Brain Abscess etiology, Fibroma, Ossifying complications, Frontal Lobe pathology, Frontal Sinus pathology, Paranasal Sinus Neoplasms complications
- Abstract
Sinonasal ossifying fibroma is a rare, slow-growing, benign bony tumour, frequently involving the maxilla and mandible in the head and neck region. Although it is known to be the second most frequent fibro-osseous tumour of paranasal sinus, to the best of our knowledge, ossifying fibroma of frontal sinus causing brain abscess has not been presented yet in the relevant literature. We present the clinical, pathological and radiological findings of ossifying fibroma of the frontal sinus associated with brain abscess.
- Published
- 2006
- Full Text
- View/download PDF
38. Clinical outcomes of neonatal hypoxic ischemic encephalopathy evaluated with diffusion-weighted magnetic resonance imaging.
- Author
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Dağ Y, Firat AK, Karakaş HM, Alkan A, Yakinci C, and Erdem G
- Subjects
- Diagnosis, Differential, Female, Humans, Hypoxia-Ischemia, Brain pathology, Infant, Newborn, Infant, Premature, Infant, Premature, Diseases diagnosis, Infant, Premature, Diseases pathology, Male, Predictive Value of Tests, Reproducibility of Results, Sensitivity and Specificity, Diffusion Magnetic Resonance Imaging methods, Diffusion Magnetic Resonance Imaging standards, Hypoxia-Ischemia, Brain diagnosis
- Abstract
Purpose: Detection of early phase neurological deficit in babies with hypoxic-ischemic encephalopathy (HIE) is the most important step to determine the appropriate preventive treatment methods. Diffusion-weighted imaging (DWI) is the most sensitive radiological modality to detect ischemic changes in the brain, in their earliest phase. Herein, we present the results of our study about the role of DWI in the diagnosis and determining the prognosis of HIE in neonates., Materials and Methods: The study included 36 cases (4 preterm, 32 term babies) who were diagnosed with HIE within 24 hours of birth and classified according to modified Sarnat staging. They were examined for the presence of neurological sequelae at 3 and 6 months of age with electroencephalography (EEG), visual evoked potential (VEP), brainstem auditory evoked potential (BAEP), and Denver II developmental screening tests. All 36 patients underwent conventional magnetic resonance (MR) imaging and DWI within the first 24 hours of birth; survivors underwent repetitive imaging exams at the end of the first week and then after a month., Results: Seventeen stage I cases (47%), 12 stage II cases (33%), and 7 stage III cases (20%) were detected. DWI obtained within the first 24 hours showed high sensitivity (100%) in detecting the permanent neurological sequelae but with very low specificity (20%). The negative predictive value of DWI in this period was 100%; however, in DWI obtained at the end of the first month, not only its sensitivity was preserved, but its specificity reached 80%. The negative predictive value of DWI in this period was preserved and the positive predictive value improved. The importance of DWI in detecting sequelae at the end of the first month was also demonstrated by McNemar (p=0.250) and Kappa (Kappa=0.719) tests. There was no difference between conventional MR imaging and DWI in detecting sequelae at the end of first month., Conclusion: DWI is superior to other imaging modalities in detecting ischemia; not only because of its high sensitivity in the early phase, but also because of its high sensitivity and specificity in the late phase. Moreover, with its high negative predictive value, DWI can be used for excluding the possibility of sequelae development in the early phase of HIE cases for medico-legal purposes.
- Published
- 2006
39. [Giant sinus of Valsalva aneurysm].
- Author
-
Karakaş HM, Kahraman B, Sağir A, and Firat AK
- Subjects
- Adult, Aortic Aneurysm diagnostic imaging, Aortic Aneurysm pathology, Diagnosis, Differential, Humans, Male, Tomography, X-Ray Computed, Aortic Aneurysm diagnosis, Sinus of Valsalva diagnostic imaging, Sinus of Valsalva pathology
- Published
- 2006
40. Brucellar breast abscess.
- Author
-
Erdem G, Karakas HM, Yetkin F, Alkan A, Firat AK, and Kahraman B
- Subjects
- Abscess diagnostic imaging, Breast Diseases diagnostic imaging, Brucellosis diagnosis, Brucellosis diagnostic imaging, Brucellosis drug therapy, Female, Humans, Magnetic Resonance Imaging, Magnetic Resonance Spectroscopy, Mammography, Middle Aged, Ultrasonography, Mammary, Abscess microbiology, Breast Diseases microbiology
- Abstract
Brucellosis is an endemic disease seen in many countries. It may affect different organ systems. Brucellar breast abscess is a rare entity. We report the radiological findings of breast abscess due to brucella. A 63-year-old female was investigated with mammography, ultrasonography, magnetic resonance imaging (MRI), and magnetic resonance spectroscopy (MRS). A mass measuring 25 x 20 x 15 mm was detected in the left breast on mammography and ultrasonography. The mass was homogenously hyperintense on T1- and T2-weighted MRI images. On contrast-enhanced T1-weighted images, peripheral capsular enhancement was found. MR spectroscopic analysis of the mass revealed elevated lipid and acetate peaks. The diagnosis was provided by fine needle aspiration biopsy and specimen culture. The lesion had diminished in size after 12 months' treatment with combined tetracycline and rifampicine.
- Published
- 2006
- Full Text
- View/download PDF
41. The effect of intravenous gadolinium-DTPA on diffusion-weighted imaging.
- Author
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Firat AK, Sanli B, Karakaş HM, and Erdem G
- Subjects
- Adolescent, Adult, Aged, Brain Diseases metabolism, Case-Control Studies, Diffusion drug effects, Female, Humans, Injections, Intravenous, Male, Middle Aged, Time Factors, Artifacts, Brain Diseases pathology, Contrast Media administration & dosage, Diffusion Magnetic Resonance Imaging, Gadolinium DTPA administration & dosage
- Abstract
Introduction: Diffusion-weighted imaging (DWI) is usually performed before injection of intravenous paramagnetic contrast medium. Occasionally, it may be necessary to perform or to repeat DWI after such administration. Our purpose was to evaluate the effect of intravenous gadodiamide (Gd [DTPA-BMA]) on DWI., Methods: DWI was performed on 88 brain lesions immediately before, immediately after, and 5-10 min following the end of 0.1 mmol/kg Gd [DTPA-BMA] administration. Signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of the lesions, and the SNRs of normal brain tissue were calculated on b=0 s/mm(2) and b=1,000 s/mm(2) DW images. Apparent diffusion coefficient (ADC) values of the lesions were measured on ADC maps. A paired t-test was used to determine the significance of differences between the values before and after administration of contrast medium., Results: The lesions consisted of 23 intraaxial and 11 extraaxial masses, 19 ischemic strokes, 15 intracranial hemorrhages and 20 demyelinating lesions. Images before and after contrast administration were not significantly different regarding SNRs and CNRs on DWI. This statement was also true for strongly enhanced lesions. However, ADC values significantly decreased after contrast medium injection on early post-contrast DWI in normal brain tissue (1%, P<0.049) and (3%, P<0.008) in lesions. By contrast, on late images, ADC values were normalized., Conclusion: Contrast medium injection had significant and time-dependent effects on ADC values. Therefore, only pre-contrast and late DW images should be used in quantitative ADC studies.
- Published
- 2006
- Full Text
- View/download PDF
42. Diffusion weighted MR findings of brain involvement in tuberous sclerosis.
- Author
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Firat AK, Karakaş HM, Erdem G, Yakinci C, and Biçak U
- Subjects
- Adolescent, Brain Neoplasms diagnostic imaging, Case-Control Studies, Child, Child, Preschool, Female, Humans, Male, Predictive Value of Tests, Tomography, X-Ray Computed, Tuberous Sclerosis diagnostic imaging, Brain Neoplasms pathology, Diffusion Magnetic Resonance Imaging methods, Tuberous Sclerosis pathology
- Abstract
Purpose: Diffusion Weighted Imaging (DWI) is effective in identifying microstructural cerebral parenchymal changes. We studied the diffusion characteristics of hamartomas and normal white matter in cases with tuberous sclerosis (TS)., Materials and Methods: Diffusion weighted images of 6 TS cases (ages between 3 - 15 years, mean 9.0 years, SD 4.4 years) that presented to our center for magnetic resonance (MR) imaging have been retrospectively evaluated. In addition to 56 non-calcified hamartomas of TS patients, apparent diffusion coefficient (ADC) values measured from frontal, parietal normal white matter, and basal ganglions of TS patients were compared with values obtained from 9 normal subjects (ages 1 - 13 years, mean 8.9 years, SD 3.4 years). Hamartomas were divided into 3 subgroups based on their locations, and the ADC values measured in these groups were compared., Results: ADC values of all hamartomas were between 838 and 2230, with a mean value of 1408 mm (2)/sec x 10(-3) (SD: 273.2); ADC values of the white matter of normal subjects were between 695 and 857, with a mean value of 776.1 mm (2)/sec x 10(-3) (SD: 44.23) (p < 0.0001). ADC values of subependymal nodules, white matter hamartomas, and subcortical tubers were 838-2230 (mean: 1440.5 mm (2)/sec x 10(-3); SD: 526.46), 1046-1622 (mean: 1328.6 mm (2)/sec x 10(-3); SD: 189.4), and 981-1973 (mean: 1417.4 mm (2)/sec x 10(-3); SD: 219.5), respectively (p = 0.666)., Conclusion: Diffusion characteristics of white matter hamartomas resulting from TS clearly differ from those of normal white matter, but no significant difference was observed in ADC values of these lesions based on their locations. Moreover, the ADC measurements of normal white matter in these cases did not differ from those of the control group, indicating that the disease does not cause a common explicit damage in white matter and central gray matter, other than hamartomas, which can be detected by DWI. DWI may only be used in the differential diagnosis of hamartomas from secondary lesions with T1 and T2W signal intensities similar to those of hamartomas and with different diffusion characteristics.
- Published
- 2006
43. Cerebral diffusional changes in the early phase of anthrax: is cutaneous anthrax only limited to skin?
- Author
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Karakas HM, Bayindir Y, Firat AK, Yagmur C, Alkan A, and Kayabas U
- Subjects
- Adolescent, Adult, Aged, Animals, Antigens, Bacterial metabolism, Antigens, Bacterial toxicity, Bacterial Toxins metabolism, Bacterial Toxins toxicity, Case-Control Studies, Child, Female, Humans, Male, Middle Aged, Organ Specificity, Telencephalon blood supply, Telencephalon drug effects, Anthrax complications, Anthrax microbiology, Bacillus anthracis physiology, Skin Diseases, Bacterial complications, Skin Diseases, Bacterial microbiology, Telencephalon pathology
- Abstract
Objectives: Characteristics of cerebral diffusion in the acute period of the anthrax infection were investigated to understand the pathophysiology of the disease., Methods: Six cutaneous anthrax patients (mean age: 33.3, SD: 18.1) and six healthy control subjects (mean age: 33.7, SS: 19.6) were examined at the acute phase of the infection with diffusion weighted imaging on 1.5 T scanner. ADC values were measured from five different cerebral locations. T-tests, logistic regression and ROC curves were used., Results: Anthrax patients were significantly different than controls regarding cortical ADC values (p<0.05). Logistic regression model accurately classified five out of the six anthrax cases (83.3%). A cut-off value of 574 mm2/s x 10(-3) was found by using ROC curve coordinates. A sensitivity of 100% and a specificity of 67% were attained by means of this value., Conclusions: This study shows the existence of cerebral parenchymal changes at microstructural level in cutaneous anthrax without neurological findings. These changes are possibly related to the components of the toxin. Our results support the general but unproven opinion that anthrax treatment does not change the existence and the effects of the toxin. Pathophysiological mechanisms towards classification should therefore be reviewed.
- Published
- 2006
- Full Text
- View/download PDF
44. Spontaneous intracranial hypotension with pituitary adenoma.
- Author
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Firat AK, Karakas HM, Firat Y, Kahraman B, and Erdem G
- Subjects
- Adenoma pathology, Adult, Female, Hematoma, Subdural etiology, Humans, Intracranial Hypotension physiopathology, Magnetic Resonance Imaging methods, Pituitary Neoplasms physiopathology, Adenoma complications, Intracranial Hypotension complications, Intracranial Hypotension pathology, Pituitary Neoplasms complications, Pituitary Neoplasms pathology
- Abstract
Spontaneous intracranial hypotension (SIH) is an unusual syndrome that is characterised by positional headache, neck rigidity, nausea and vomiting. The characteristic magnetic resonance imaging (MRI) findings are diffuse smooth pachymeningeal thickening and enhancement, downward displacement of posterior fossa structures and pituitary gland enlargement. An unusual case of SIH with pituitary macro-adenoma and subsequent subdural haemorrhage is presented, and its clinical picture, MRI findings and possible pathophysiological mechanism are discussed.
- Published
- 2006
- Full Text
- View/download PDF
45. Computed tomography virtual laryngoscopy: comparison between radiological and otolaryngological evaluations for laryngeal carcinoma.
- Author
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Firat Y, Aygenç E, Firat AK, Oto A, Selçuk A, Firat MM, and Ozdem C
- Subjects
- Adult, Aged, Female, Humans, Image Processing, Computer-Assisted methods, Laryngeal Neoplasms pathology, Male, Middle Aged, Neoplasm Invasiveness, Predictive Value of Tests, Sensitivity and Specificity, Laryngeal Neoplasms diagnostic imaging, Laryngoscopy methods, Tomography, X-Ray Computed methods
- Abstract
Objectives: We evaluated the utility of computed tomography virtual laryngoscopy (CTVL) in identifying endolaryngeal lesions in laryngeal tumors., Patients and Methods: Virtual laryngoscopic images were obtained from axial CT scans of 21 patients with known laryngeal carcinoma. Findings from rigid telescopic videolaryngoscopy (RTV) and CTVL images were evaluated and compared with reference to operative records., Results: Lesions localized in the base of the tongue, pyriform sinus, aryepiglottic folds, and arytenoids were well visualized by both RTV and CTVL. The two techniques were not found effective in identifying lesions of the ventricular bands, ventricular cavities, and the anterior commissure. Virtual laryngoscopy was superior to RTV in the visualization of the subglottic area and vocal cords., Conclusion: Virtual laryngoscopy is a noninvasive and reliable technique that provides visualization of endolaryngeal surfaces and tumor extension. It may be beneficial in staging larynx carcinoma and planning the most appropriate surgical procedure.
- Published
- 2006
46. The incidence of atopy in adults with recurrent secretory otitis media: screening with Phadiatop.
- Author
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Firat Y, Koç C, Olcay I, Selçuk A, Firat AK, and Ozdem C
- Subjects
- Adult, Dermatitis, Atopic blood, Dermatitis, Atopic complications, Dermatitis, Atopic epidemiology, Female, Humans, Immunoglobulin E blood, Incidence, Male, Middle Aged, Otitis Media with Effusion pathology, Predictive Value of Tests, Recurrence, Sensitivity and Specificity, Turkey epidemiology, Dermatitis, Atopic diagnosis, Otitis Media with Effusion complications, Skin Tests standards
- Abstract
Objectives: This is a preliminary report of a relatively new method, Phadiatop, in screening atopic adult patients with recurrent secretory otitis media (SOM). The sensitivity and specificity, and its use in atopic adult patients with recurrent SOM were evaluated., Patients and Methods: Eighty-four patients (54 females, 30 males; mean age 36.7; range 19 to 62 years) who were diagnosed as recurrent SOM were included in the study. The patients were evaluated with respect to history, laboratory tests, skin-prick test, and total IgE. Patients with at least one positive skin-prick test result and/or a high total IgE level with a positive history were considered to be in atopic status., Results: According to certain criteria, atopy was detected in 31 of 84 patients. Negative Phadiatop values were found in all non-atopic patients as well as in one atopic patient. Among 31 patients having atopy, 30 patients showed positive Phadiatop values (specificity 1.00, sensitivity 0.97, positive predictive value 1.00, negative predictive value 0.98)., Conclusion: These results indicate that Phadiatop is an effective test to detect atopy in patients with recurrent SOM.
- Published
- 2006
47. Quantitative evaluation of brain involvement in ataxia telangiectasia by diffusion weighted MR imaging.
- Author
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Firat AK, Karakaş HM, Firat Y, and Yakinci C
- Subjects
- Adolescent, Atrophy, Brain blood supply, Cerebellar Cortex blood supply, Cerebellar Cortex pathology, Cerebellum blood supply, Cerebellum pathology, Child, Echo-Planar Imaging methods, Female, Humans, Image Processing, Computer-Assisted methods, Male, Microcirculation pathology, Prospective Studies, Sensitivity and Specificity, Ataxia Telangiectasia diagnosis, Brain pathology, Diffusion Magnetic Resonance Imaging methods
- Abstract
Objective: To evaluate the value of diffusion weighted imaging (DWI) in diagnosing ataxia telangiectasia (AT) and to investigate the spatial distribution of cerebral microstructural changes caused by the disease., Methods: Six AT patients (9-13 years) and nine healthy control subjects were examined on 1.5 T scanner. In addition to conventional MR images, DWI were performed with a fat suppressed, multishot spin echo EPI sequence using B values of 0, 500 and 1000 s/mm2. Mean ADC values were measured from 16 different supra and infratentorial location. The difference between controls and AT patients regarding ADC values, and the accuracy, sensitivity and specificity of them in discrimination were analyzed with t-tests, logistic regression analysis, ANOVA and ROC curves., Results: Conventional images of the controls were normal. In AT patients, the only conventional MR abnormality was cerebellar atrophy. The difference between both groups regarding mean ADC values was not significant for any of the cerebral structures. In contrary to cerebrum, cerebellar mean ADC values of patients and controls were statistically different (p < 0.011-0.0001). Patients and controls were classified with 100% accuracy using ADC values of cerebellar white matter and cortex together (p < 0.016). The cut-off ADC value (0.699 mm2/s) for middle cerebellar cortex had produced highest (100%) sensitivity and specificity. There was a difference between superior, middle and inferior cerebellar cortex regarding ADC values (p < 0.026). Superior cerebellar cortex (0.987+/-0.1956 mm2/s) had higher ADC values than the middle and inferior cerebellar cortex., Conclusion: DWI provides a supplementary and objective imaging finding in AT. This finding is highly accurate in the radiological discrimination of healthy subjects and AT. Our findings also implicate that AT causes a diffuse atrophy and mostly affects superior part of the cortex.
- Published
- 2005
- Full Text
- View/download PDF
48. Protective role of melatonin in pinealectomized rat brains: in vivo magnetic resonance spectroscopic analysis.
- Author
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Hascalik S, Celik O, Karakas HM, Parlakpinar H, Firat AK, and Ozsahin M
- Subjects
- Animals, Aspartic Acid analogs & derivatives, Aspartic Acid analysis, Choline analysis, Creatine analysis, Magnetic Resonance Spectroscopy, Rats, Rats, Wistar, Brain Chemistry drug effects, Melatonin pharmacology, Neuroprotective Agents pharmacology, Pineal Gland physiology
- Abstract
The goal of this study was to investigate the effect of melatonin on basic cerebral metabolites in pinealectomized (Px) rat brains. Twenty-one rats were randomly divided into three groups with seven rats per group. The study groups included sham-operated rats, Px rats and Px rats treated with melatonin. Melatonin administration began at 60 days following pinealectomy and continued for 21 days. At the end of the study, in vivo single voxel magnetic resonance spectroscopy was performed on whole brains to determine choline (Cho), creatine and N-acetyl aspartate (NAA) concentrations. Px rats had significantly lower NAA levels (P<0.05), and significantly higher Cho levels (P<0.05) when compared with sham-operated rats. Administration of melatonin had normalized NAA and Cho levels in Px rats. We propose that pinealectomy causes significant changes in cerebral metabolites which are compatible with neural loss. Melatonin administration prevents the disruptive effects of pinealectomy on brain tissue.
- Published
- 2005
- Full Text
- View/download PDF
49. Selective intraarterial nimodipine treatment in an experimental subarachnoid hemorrhage model.
- Author
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Firat MM, Gelebek V, Orer HS, Belen D, Firat AK, and Balkanci F
- Subjects
- Animals, Female, Injections, Intra-Arterial, Male, Rabbits, Subarachnoid Hemorrhage complications, Vasospasm, Intracranial etiology, Calcium Channel Blockers administration & dosage, Disease Models, Animal, Nimodipine administration & dosage, Subarachnoid Hemorrhage drug therapy, Vasospasm, Intracranial drug therapy
- Abstract
Background and Purpose: Cerebral vasospasm secondary to subarachnoid hemorrhage (SAH) has been a serious clinical problem. The aim of the present study is to evaluate the efficacy of selective intraarterial (IA) nimodipine treatment in a rabbit model of chronic cerebral vasospasm., Methods: Twenty-two adult New-Zealand rabbits of either sex, weighing 2500-3800 g were used for this study. Following a control angiography, all animals received 1 mL of fresh unheparinized autologuous arterial blood into the cisterna magna. Three days later, the presence of vasospasm was demonstrated angiographically by selective vertebral artery injection. The experimental design was as follows: separate groups of animals (n = 5, in each group) received nimodipine (0.05 mg/kg), papaverine (6 mg/kg), or vehicle intraarterially, after placement of a microcatheter into the vertebral artery. Another group (n = 5) received nimodipine (0.05 mg/kg) directly into the cisterna magna, and vehicle injection was made into cisterna magna in two other animals. Thirty minutes after treatment, angiographies were repeated and changes in arterial diameter were expressed as percentages of control., Results: IA nimodipine and IA papaverine were effective in relieving veretebral and basilary vasospasm (P < .05). IA nimodipine was more effective than IA papaverine (P < .05). IA nimodipine was not more effective than intrathecal (IT) nimodipine in relieving vertebral artery vasospasm, although it was more effective than IT nimodipine in basilar artery. Vehicle injections (IA or IT) failed to reverse the vasospasm induced by autologuous blood injection., Conclusion: This study showed that selective IA nimodipine treatment may be considered as an alternative in the treatment of chronic vasospasm following SAH.
- Published
- 2005
50. Spontaneous bilateral intrasphenoidal lateral encephaloceles: CT and MRI findings.
- Author
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Firat AK and Firat Y
- Subjects
- Cerebrospinal Fluid Rhinorrhea diagnosis, Cerebrospinal Fluid Rhinorrhea physiopathology, Encephalocele physiopathology, Encephalocele surgery, Humans, Magnetic Resonance Imaging, Male, Meningocele physiopathology, Meningocele surgery, Middle Aged, Sphenoid Sinus diagnostic imaging, Time Factors, Tomography, X-Ray Computed, Encephalocele diagnosis, Meningocele diagnosis, Sphenoid Sinus physiopathology
- Abstract
Lateral intrasphenoidal encephaloceles are rare anomalies. We describe a unique case in which spontaneous bilateral intrasphenoidal lateral encephaloceles were discovered in a 53-year-old man during a work-up for cerebrospinal fluid leak. We discuss our clinical findings and the results of preoperative computed tomography and magnetic resonance imaging.
- Published
- 2004
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