Demet Funda Bas
Hacettepe University
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Publication
Featured researches published by Demet Funda Bas.
Epilepsy Research | 2015
Nese Dericioglu; Ezgi Yetim; Demet Funda Bas; Nuray Bilgen; Gulsen Caglar; Ethem Murat Arsava; Mehmet Akif Topcuoglu
Video-EEG monitoring is the ultimate way to diagnose non-convulsive status epilepticus (NCSE) in intensive care units (ICU). Usually EEG recordings are evaluated once a day by an electrophysiologist, which may lead to delay in diagnosis. Digital EEG trend analysis methods like amplitude integrated EEG (aEEG) and density spectral array (DSA) have been developed to facilitate recognition of seizures. In this study, we aimed to investigate the diagnostic utility of these methods by non-expert physicians and ICU nurses for NCSE identification in an adult neurological ICU. Ten patients with NCSE and ten control patients without seizures were included in the study. The raw EEG recordings of all subjects were converted to both aEEG and DSA and displayed simultaneously without conventional EEG. After training for seizure recognition with both methods, two physicians and two nurses analyzed the visual displays individually, and marked seizure timings. Their results were compared with those of a study epileptologist. Participants analyzed 615h of EEG data with 700 seizures. Overall, 63% of the seizures were recognized by all, 15.6% by three, 11.6% by two, 8.3% by one rater and only 1.5% were missed by all of them (sensitivity was 88-99%, and specificity was 89-95% when the ratings were assessed as 1-h epochs). False positive rates were 1 per 2h in the study and 1 per 6h in the control groups. Interrater agreement was high (κ=0.79-0.81). Bilateral independent seizures and ictal recordings with lower amplitude and shorter duration were more likely to be missed. There was no difference in performance between the rating of physicians and nurses. Our study demonstrates that bedside nurses, ICU fellows and residents can achieve acceptable level of accuracy for seizure identification using the digital EEG trend analysis methods following brief training. This may help earlier notification of the electrophysiologist who is not always available in ICUs.
Stroke | 2015
Ethem Murat Arsava; Demet Funda Bas; Enver Atalar; Arzu Ceylan Has; Kader K. Oguz; Mehmet Akif Topcuoglu
Background and Purpose— The widespread use of ambulatory cardiac monitoring has not only increased the detection of high-risk arrhythmias like persistent and paroxysmal atrial fibrillation (AF), but also made it possible to identify other aberrations such as short-lasting (<30 seconds) irregular runs of supraventricular tachycardia. Ischemic stroke phenotype might be helpful in understanding whether these nonsustained episodes play a similar role in stroke pathophysiology like their persistent and paroxysmal counterparts. Methods— In a consecutive series of patients with ischemic stroke, we retrospectively determined clinical and imaging features associated with nonsustained AF (n=126), defined as <30-second-lasting supraventricular tachyarrhythmias with irregular RR interval on 24-hour Holter monitoring, and compared them to patients with persistent/paroxysmal AF (n=239) and no AF (n=246). Results— Patients with persistent/paroxysmal AF significantly differed from patients with nonsustained AF by a higher prevalence of female sex (odds ratio [95% confidence interval], 1.8 [1.1–2.9]), coronary artery disease (1.9 [1.1–3.0]), and embolic imaging features (2.7 [1.1–6.5]), and lower frequency of smoking (0.4 [0.2–0.8]) and hyperlipidemia (0.5 [0.3–0.8]). In contrast, patients with no AF were younger (0.5 [0.4–0.6] per decade) and more likely to be male (1.7 [1.0–2.8]) in comparison with nonsustained AF population. The prevalence of nonsustained AF was similar among cryptogenic and noncryptogenic stroke patients (32% versus 29%). Voxel-wise comparison of lesion probability maps revealed no significant difference between cryptogenic stroke patients with and without nonsustained AF. Conclusions— Clinical features of patients with nonsustained AF exhibited an intermediary phenotype in between patients with persistent/paroxysmal AF and no AF. Furthermore, imaging features did not entirely resemble patterns observed in patients with longer durations of AF.
Journal of Neurochemistry | 2012
Demet Funda Bas; Mehmet Akif Topcuoglu; Yasemin Gursoy-Ozdemir; Isil Saatci; Ebru Bodur; Turgay Dalkara
Cerebral reperfusion injury may account for complications of thrombolysis and endovascular recanalization. Experimental studies have shown that brain matrix metalloproteinase (MMP) activity increases during reperfusion and is correlated with oxidative/nitrative stress. Increased plasma MMP levels have been reported in stroke, but no information is available for reperfusion‐induced plasma MMP and 3‐nitrotyrosine (3‐NT, a marker of oxidative/nitrative stress) changes immediately after recanalization. We obtained plasma from 29 patients undergoing endovascular recanalization, 12 patients treated with thrombolysis, and six control patients having diagnostic angiogram before and 1,3, and 24 h after treatment to investigate the effect of cerebral reperfusion on plasma MMP gelatinolytic activity and 3‐NT level. Hypoperfusion was shown distal to the stenotic artery in endovascular treatment patients. Presence of an occluded artery and recanalization was documented in thrombolysis patients. A significant increase was detected in plasma 3‐NT levels 3 and 24 h after stenting/angioplasty. Plasma MMP‐9 gelatinolytic activity rose more than 50% of the pre‐treatment level in 12 of 29 patients. However, this was not statistically significant and not correlated with any of the clinical or radiological correlates of reperfusion injury (e.g., hyperperfusion and hemorrhage). After thrombolysis, a significant increase in plasma MMP‐9 gelatinolytic activity at 3 and 24 h and the cleaved form of MMP‐9 were detected. 3‐NT levels increased by 44% and 62% at 3 and 24 h, which did not achieve statistical significance, but was highly correlated with admission NIH Stroke Scale (r = 0.930 p < 0.001). No change was detected in MMP‐2 in all groups. In conclusion, these data suggest that the increased plasma MMP‐9 levels is not a direct measure of MMP‐9 activity in the reperfused brain but rather a consequence of tissue plasminogen activator infusion, whereas plasma 3‐NT levels appear to originate from the reperfused brain vasculature. The changes in 3‐NT levels may therefore be useful to monitor oxygen/nitrogen radical formation during reperfusion with serial measurements.
Journal of Stroke & Cerebrovascular Diseases | 2009
Demet Funda Bas; Kader Karli Oguz; Kivilcim Yavuz; Mehmet Akif Topcuoglu
A 22-year-old woman with congenital afibrinogenemia presented with acute-onset rapidly progressive quadriparesis as a result of spinal cord infarction caused by vertebral artery dissection. Magnetic resonance imaging scans showed microhemorrhages in addition to edematous swelling suggesting acute ischemia throughout cervical and upper thoracic portions of the spinal cord. Fat-saturated T1-weighted magnetic resonance examination and digital subtraction angiography studies demonstrated cervical vertebral artery dissection on the right. This case provides an example of how a primary bleeding disorder could result in a severe ischemic complication caused by an occlusive vessel wall hematoma. Along with other reports, diagnostic and therapeutic aspects of this paradoxical situation were discussed in the particular setting of acute spinal cord ischemia.
Journal of Stroke & Cerebrovascular Diseases | 2015
Mehmet Yasir Pektezel; Demet Funda Bas; Mehmet Akif Topcuoglu; Ethem Murat Arsava
Recombinant human chorionic gonadotropin (hCG) is commonly misused as a weight reducing or performance enhancing agent but is associated with increased risk of thromboembolic events. A 29-year-old female with a history of obesity was admitted to our center with a diagnosis of ischemic stroke. Etiologic workup revealed a large patent foramen ovale and history of recent use of hCG as part of a weight loss regimen. This report highlights the potential complications of hCG therapy, particularly when used for unapproved indications and without medical supervision.
Internal Medicine | 2008
Demet Funda Bas; Kader Karli Oguz; Mehmet Akif Topcuoglu
Internal Medicine | 2010
Gul Yalcin-Cakmakli; Kader Karli Oguz; Ali Shorbagi; Demet Funda Bas; Begum Ergan-Arsava; Mahir Kunt; Mehmet Akif Topcuoglu
Internal Medicine | 2008
Demet Funda Bas; Erhan Akpinar; Kader Karli Oguz; Mehmet Akif Topcuoglu
Türk Beyin Damar Hastalıkları Dergisi | 2016
Halil Onder; Ethem Murat Arsava; Demet Funda Bas; Kader Karli Oguz; Mehmet Akif Topcuoglu
Noro Psikiyatri Arsivi | 2016
Uygar Utku; Demet Funda Bas; Elyar Sadeghi Hokmabadi; Elif Gencer; Atilla Özcan Özdemir