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Acute-Phase Vitamin B12 and Folic Acid Levels in Patients with Ischemic and Hemorrhagic Stroke: İs There a Relationship with Prognosis?
(Maney Publishing, 2010) Bayır, Ayşegül; Ak, Ahmet; Özdinç, Şerife; Seydanoglu, Abdüsselam; Köstekçi, Şenol Kadir; Kara, Fatih
Objective: The aim of this study was to investigate blood folic acid and vitamin B12 levels in patients with ischemic and hemorrhagic stroke patients and correlate these levels with prognosis. Methods: Patients presenting within 3 hours of onset of ischemic or hemorrhagic strokes were approached for participation in the study. Diagnosis was made by clinical examination and head computed tomography scan. Venous blood samples were taken for determination of blood folic acid and vitamin B12 levels. Parameters were evaluated with respect to stroke type and according to Glasgow coma scale (<= 8 or >= 9). Results: Eighty-seven patients with ischemic stroke (mean age: 65 +/- 10 years, 53% male) and 27 patients with hemorrhagic stroke (mean age: 60 +/- 10 years, 56% male) were included in the study. A significant direct correlation was found between Glasgow coma scale and mean plasma B12 levels in ischemic, but not hemorrhagic, stroke (r=112.75 and p=0.007, respectively). A significant direct correlation was found between Glasgow coma scale and mean plasma folic acid levels in hemorrhagic, but not ischemic, stroke (r=1.03 and p=0.017, respectively). In patients with Glasgow coma scale <= 8 (either hemorrhagic or ischemic stroke), a significant direct correlation was found between Glasgow coma scale and blood vitamin B12 levels. Vitamin B12 levels were significantly lower in patients with Glasgow coma scale (8 than in patients with Glasgow coma score >= 9 (p=0.04). Conclusions: In patients with ischemic stroke, low vitamin B12 levels, and in patients with hemorrhagic stroke, low blood folic acid levels, are associated with lower Glasgow coma scale values and higher hospital mortality.
Akut Koroner Sendromların Erken Döneminde Akut Faz Reaktanlarının Belirlenmesi
(2002) Gül, Mehmet; Kafalı, Mehmet Ertuğrul; Ak, Ahmet; Tokaç, Mehmet; Bayır, Ayşegül
Son yıllarda iskemik kalp hastalıklarının oluşumu ve gelişiminde inflamasyonun rolü birçok klinik ve deneysel çalışmayla yoğun olarak araştırılmaktadır. Akut koroner sendromlar iskemik kalp hastalıklarının patolojik ve klinik olarak en ciddi formudur. Bu çalışmada akut koroner sendromlu olguların acil servise başvuru sonrası ilk 12 saatlik erken dönemindeki inflamasyon belirteçlerinin değişimini araştırdık. Bu amaçla akut miyokard infarktüsü (AMI) ve anstabil angina pektoris (UAP) tanısı konulan olgularda plazma akut faz reaktanlarının [Lipoprotein a (Lp a), beyaz küre, fibrinojen, C-reaktif protein (CRP), kompleman 3 ve 4 (C3, C4)] acil servise başvuru sırasında ve 12 saat sonraki değerleri ölçülerek inflamasyon şiddeti yönünden karşılaştırıldı. Yöntem: Çalışmaya göğüs ağrısı şikayetiyle İlk ve Acil Yardım Kliniği'ne başvurup, fizik muayene ve laboratuar tetkikleri ile UAP (54 hasta) ve AMI (58 hasta) tanısı konulan çalışma grubu ve herhangi bir yakınması bulunmayan sağlıklı gönüllü kontrol grubu (50 birey) dahil edildi. İlk ve Acil Yardım Kliniği'ne kabul edilen çalışma grubundan başvuru anında ve on iki saat sonra, kontrol grubundan ise on iki saat arayla iki kez venöz kan örneği alındı. Bulgular: UAP'li olgularda ilk 12 saatlik dönemde fibrinojen ve C4 değerlerindeki azalma, AMI'lü olgularda lipoprotein (a) değerlerindeki artış anlamlı bulundu (sırasıyla, P0.016, P0.029, P0.047). Sonuç: Akut koroner sendromun her iki formunda da acil servise kabulden sonraki ilk 12 saatlik dönemde inflamatuar süreç devam etmekte, özellikle fibrinojen ve C4 gibi inflamasyon belirteçlerinin plazma değerlerinde azalma görülmektedir.
Autologous Transplantation of Arterial Cells Improves Cardiac Function in a Rabbit Model of Infarcted Myocardium
(Mary Ann Liebert, Inc, 2010) Tokaç, Mehmet; Aktan, Murad; Ak, Ahmet; Duman, Selçuk; Tokgözoğlu, Lale; Aygül, Nazif; Paksoy, Yahya; Porat, Yael
Cellular cardiomyoplasty is a promising approach for the treatment of severe heart failure. However, the question which cell line is the best to use is still a matter of debate. In this study, we aimed to evaluate the efficacy of arterial media-intima cell suspension (AMICS) transplantation in rabbit myocardial infarct model. The study was divided into 2 groups: group A (the cell-treated group, n = 9) and group B (the medium injection group, n = 8). Group A was further divided into 2 subgroups as branch-1 (treated with unlabeled cells) and branch-2 (treated with iron-labeled cells). The experimental myocardial infarction (MI) was induced by ligation of left anterior descending coronary artery with a combination of cryoinjury. Ten days after the MI, cells obtained from autologous femoral arteries were injected into the injured myocardium of group A, while group B received an injection of only DMEM medium. Clinical, echocardiographic, and histopathologic evaluations were done. As compared to the ninth day values, echocardiography showed a significant improvement in systolic functions and left ventricular (LV) dimensions of the cell-treated group on the 30th day. In the heart biopsy sections of branch-1, the immunostained injected cells were observed to exist closely, suggesting an organization. Cells existing separately and lumen-like structure organizations stained positive with both smooth muscle cell (SMC) a-actin and Prussian Blue were also showed in the histological observation of branch-2. Autologous AMICS transplantation seems to be a feasible and efficacious method for cellular cardiomyoplasty in our rabbit model.
Blunt chest trauma as a cause of acute myocardial infarction
(TAYLOR & FRANCIS LTD, 2014) Kara, H.; Avcı, A.; Akıncı, M.; Değirmenci, S.; Bayır, Ayşegül; Ak, Ahmet
Chest pain after thoracic trauma may be a symptom of cardiac injury or myocardial infarction. A 63-year-old healthy man had chest pain after blunt chest trauma in a motor vehicle accident. Chest computed tomography scan showed a displaced sternal fracture, lung contusion in the left upper lobe, atelectasis and consolidation in both lower lobes, and bilateral haemothorax. Electrocardiography showed ST elevation (2 mm) in leads II, III, and aVF and ST depression (2 mm) in leads I and aVL, consistent with acute inferior myocardial infarction. Urgent coronary angiography showed ostial occlusion of the right coronary artery. After the right coronary occlusion was passed with a guide wire, dissection of the right coronary artery was observed and treated with a balloon and stent to reestablish normal flow. This case emphasizes the importance of a high index of suspicion for coronary artery injury and myocardial infarction after blunt chest trauma.
Böcek Sokmasına Bağlı Anaflakside MRG Bulguları: Olgu Sunumu
(2001) Aydoğdu Kıreşi, Demet; Emlik, Dilek; Ak, Ahmet; Karabacakoğlu, Aydın; Karaköse, Serdar
Anamnezinde böcek ısırması olan, anaflaksinin klinik bulguları ile birlikte bilinç kaybı ile gelen olgunun manyetik rezonans görüntüleme (MRG) bulguları literatür bilgileri ile birlikte tartışıldı. Olgu sunumu: 29 yaşında, daha önceden hiçbir şikayeti olmayan, hasta yakınları tarafından böcek ısırması anamnezi verilen olguda fizik muayenede anaflaksiye ait bulgular, bilinç kaybı ve hipotansiyon mevcuttu. MRG'de bilateral parieto-oksipital bölgede gri cevherde, bilateral kaudat nukleusta ve putamende T1'de hipo-T2'de hiperintens lezyonlar görüldü. Sonuç: Yetişkinlerde görülen hipoksik iskemik beyin hasarının nadir sebeplerinden biri olan böcek sokmasına bağlı anaflakside manyetik rezonans görüntüleme bulguları tanıda yardımcı olabilir.
A case of rhabdomyolysis related with low intensity body building exercise
(Ondokuz Mayis Universitesi, 2015) Kara, Hasan; Bayır, Ayşegül; Ak, Ahmet; Doğru, Ali; Değirmenci, Selim; Akıncı, Murat
Rhabdomyolysis is a clinical and biochemical syndrome resulting from the acute necrosis of muscle fibers and the leak of cellular elements into circulation. It can usually develop after trauma and severe exercises. However, it may also occur following low intensity exercises. In our case, a 24-year-old man was admitted to our emergency department because of severe abdominal pain after low intensity bodybuilding exercise. The development of an acute exertional rhabdomyolysis was confirmed by the increased serum enzyme levels. The patient was treated with intravenous sodium chloride, and sodium bicarbonate. In patients admitted to the emergency room after trauma or intensive exercise who are suspected of having rhabdomyolysis, the serum creatine phosphokinase, creatinine and potassium levels should be evaluated and if found to be high, fluid treatment should be started early to avoid any potential complications. © 2015 OMU.
Causes of poisoning in patients evaluated in a hospital emergency department in Konya, Turkey
(PAKISTAN MEDICAL ASSOC, 2014) Kara, Hasan; Bayır, Ayşegül; Değirmenci, Selim; Kayış, Seyit Ali; Akıncı, Murat; Ak, Ahmet; Ağaçayak, Ahmet
Objectives: To evaluate demographic and clinical characteristics of patients with poisoning at a community hospital. Methods: The retrospective study comprised records of patients who were admitted to the emergency department of Konya Numune Hospital, Turkey, because of poisoning between January 1, 2009, and December 31, 2011. Data was evaluated for age, gender, educational status, occupation, arrival time, mechanism of intoxication, body temperature, pulse, respiratory rate, Glasgow Coma Scale score, treatment applied, duration of hospital stay, duration of follow-up, test results, final diagnosis, clinical disposition, and outcome. Agents causing the poisoning were also determined. Results: Records of 1036 patients were evaluated. Of them, 764(74%) were female and 272(26%) were male. The predominant age range was 15-24 years in 617(60%) patients. The median time from substance exposure to admission to the emergency department was 2 hours. The most common cause of poisoning was attempted suicide in 955 [92%] patients and drug intoxication was the agent involved in 932 (90%). In the 15-24 year age range, there were 469(76%) female patients. Of the total female population in the study, 716(94%) attempted suicide. The median hospital stay was 24 hours. There were 908(88%) patients who were advised to seek further evaluation at the psychiatry clinic, and 9 (0.9%) patients were admitted to the psychiatry inpatient units after medical treatment. In patients who were hospitalized and followed up, 1 (0.1%) died because of multiple drug poisoning. Conclusion: Most admissions to the emergency department for poisoning related to young women had used drugs during a suicide attempt.
Cerebrovascular ischaemia after carbon monoxide intoxication
(SINGAPORE MEDICAL ASSOC, 2015) Kara, Hasan; Bayir, Aysegul; Ak, Ahmet; Degirmenci, Selim
Carbon monoxide intoxication is the most prevalent cause of death from carbon monoxide poisoning. We herein report the case of a 56-year-old man who was found unconscious and smelled of smoke after exposure to carbon monoxide from a heater. He scored 5 on the Glasgow Coma Scale, and had respiratory insufficiency and elevated troponin I, creatine kinase-MB fraction and carboxyhaemoglobin levels. He was treated by mechanical ventilation. After regaining consciousness, brain magnetic resonance imaging showed diffusion restriction in the left occipital lobe; there was a loss of vision (right temporal hemianopsia), which improved by the follow-up session. Carbon monoxide intoxication may cause neurologic and cardiac sequelae, and the initial treatment includes oxygen therapy. Acute carbon monoxide poisoning can cause serious injury to the brain, heart and other organs; the most severe damages that could be inflicted to the brain include cerebral ischaemia and hypoxia, oedema, and neural cell degeneration and necrosis.
D-dimer and D-dimer/fibrinogen ratio in predicting pulmonary embolism in patients evaluated in a hospital emergency department
(MANEY PUBLISHING, 2014) Kara, Hasan; Bayır, Ayşegül; Değirmenci, Selim; Kayış, Seyit Ali; Akıncı, Murat; Ak, Ahmet; Çelik, Bülent; Doğru, Ali; Öztürk, B.
Objectives: The D-dimer level, fibrinogen level, and D-dimer/fibrinogen ratio are used in the diagnosis of pulmonary embolism, but results vary. We evaluated these parameters in the diagnosis of pulmonary embolism in emergency clinic patients. Methods: In this prospective study, 200 patients (pulmonary embolism, 100 patients; no pulmonary embolism, 100 patients) had D-dimer and fibrinogen levels measured before intervention. Pulmonary embolism was diagnosed with computed tomography angiography or ventilation-perfusion scintigraphy. Results: Compared with patients who did not have pulmonary embolism, patients who had pulmonary embolism had significantly greater mean D-dimer level (pulmonary embolism, 6 +/- 7 mu g/ml; no pulmonary embolism, 1 +/- 1 mu g/ml; P <= 0.001) and D-dimer/fibrinogen ratio (pulmonary embolism, 3 +/- 3; no pulmonary embolism, 0.4 +/- 0.4; P <= 0.001), but similar mean fibrinogen levels (pulmonary embolism, 337 +/- 184 mg/dl; no pulmonary embolism, 384 +/- 200 mg/dl; not significant). In patients who had pulmonary embolism, mean D-dimer level and D-dimer/fibrinogen ratio were greater in high-risk than non-high-risk patients. With D-dimer cutoff 0.35 mu g/ml, sensitivity was high (100%) and specificity was low (27%) for pulmonary embolism. With D-dimer/fibrinogen ratio cutoff 0.13, sensitivity was high (100%) and specificity was low (37%) for pulmonary embolism. Conclusion: A D-dimer level <0.35 mu g/ml may exclude the diagnosis of pulmonary embolism. At a D-dimer cutoff 0.5 mu g/ml and D-dimer/fibrinogen ratio cutoff 1.0, the D-dimer/fibrinogen ratio may have better specificity than D-dimer level in the diagnosis of pulmonary embolism, but the D-dimer/fibrinogen ratio may lack sufficient specificity in screening.
Deneysel akut organik fosfor toksisitesi tedavisine eklenen e vitaminin olumlu etkileri
(2011) Bayır, Ayşegül; Yıldız, Mesut; Kara, Hasan; Köylü, Öznur; Kocabaş, Rahim; Ak, Ahmet
AmaçPestisit zehirlenmelerinde reaktif oksijen türevlerinin artmış üretimine bağlı olarak oksidatif stres geliştiği bildirilmiştir. Doku ROS seviyeleri doku hasarının en önemli göstergelerindendir. Bu çalışmada, akut organofosfat (OF) zehirlenmesinde ek olarak kullanılacak E vitamininin tedavisinin kandaki ve karaciğer dokusundaki kolin esteraz (KE) ve malondialdehit (MDA) düzeyleri üzerine etkilerini araştırmak ve sadece antidot tedavisi verilen grup ile karşılaştırarak OF zehirlenmesi tedavisinde kullanılıp kullanılamayacağını belirlemektir.Gereç ve YöntemÇalışmada 20 Yeni Zelanda cinsi tavşan randomize olarak sham (n8), pralidoksim (PAM)atropin (n6) ve E vitamini (n6) olarak 3 gruba ayrıldı. Her denekten toksisite öncesi plazma KE, serum ve eritrosit MDA değerlerini ölçmek için kan örnekleri alındıktan sonra orogastrik yoldan 50 mg/kg 2.2-diklorvinil dimetil fosfat verildi. PAMatropin grubundaki deneklere 30 mg/kg IV bolus, ardından 15 mg/kg PAM ve 0.05 mg/kg atropin her 4 saatte İV verildi. E vitamini grubundaki deneklere benzer atropin ve PAM tedavisine ilaveten 250 mg/kg E vitamini tek doz İM uygulandı. Deneklerden tedavi başlatıldıktan sonra 12. ve 24. saatlerde kan örnekleri alındı. Tüm deneklerden aynı parametreleri değerlendirmek üzere karaciğer dokusu örnekleri alındı. Denekler yüksek dozda İV anestezik verilerek sakrifiye edildiler. BulgularE vitamini grubunun eritrosit MDA’sı PAMatropin grubundan anlamlı düşük (p0.003) tespit edildi. E vitamini grubunun karaciğer dokusundaki KE düzeyi PAMatropin grubundan anlamlı olarak yüksekti (p0.001). E vitamini grubundaki tavşanların karaciğer doku MDA’sı PAM-atropin grubundan anlamlı olarak düşüktü (p0.001). SonuçAkut OF zehirlenmesinde antidot tedavisine eklenen E vitamininin hem eritrosit ve karaciğer dokusu lipid peroksidasyonu üzerine hem de karaciğer dokusu KE aktivitesi üzerine iyileştirici etkisi vardır.
Diagnostic value of neutrophil-to-lymphocyte ratio in emergency department patients diagnosed with acute pancreatitis
(CUKUROVA UNIV, FAC MEDICINE, 2016) Kara, Hasan; Dogru, Ali; Degirmenci, Selim; Bayir, Aysegul; Ak, Ahmet; Kafali, Mehmet Ertugrul; Nazik, Emet Ebru
Purpose: Decreased lymphocyte count and increased neutrophil count may be associated with severe sepsis, bacteremia, and surgical stress. The neutrophil-to-lymphocyte ratio (NLR) may be used to assess inflammatory conditions and surgery. We evaluated whether NLR may be useful in the differentiation between biliary and nonbiliary acute pancreatitis. Material and Methods: Data from patients aged >18 years who were diagnosed with acute pancreatitis between January 2011 and July 2014 were evaluated retrospectively. Patients were grouped as having biliary or nonbiliary pancreatitis. The white blood cell, neutrophil, and lymphocyte counts and NLR were evaluated and compared between the 2 groups. Results: In the 225 patients with acute pancreatitis (mean age, 59+/-18 y; 81 male patients [36%]), most patients had biliary pancreatitis (biliary, 144 patients [64%]; nonbiliary, 81 patients [36%]). Frequency of hypertension and mean arterial pressure were lower in patients who had biliary than nonbiliary pancreatitis. The mean white blood cell, neutrophil, and platelet counts were greater in patients who had nonbiliary than biliary pancreatitis. Conclusions: Although the NLR was increased in acute pancreatitis, there were no differences in NLR between patients who had biliary or nonbiliary acute pancreatitis. Therefore, the NLR is not useful in differentiating biliary from nonbiliary acute pancreatitis.
Dyspnoea and chest pain as the presenting symptoms of pneumomediastinum: two cases and a review of the literature
(CLINICS CARDIVE PUBL PTY LTD, 2015) Kara, Hasan; Uyar, Hasan Gazi; Degirmenci, Selim; Bayir, Aysegul; Oncel, Murat; Ak, Ahmet
Pneumomediastinum is the presence of air in the mediastinum. It may occur as spontaneous, traumatic, or iatrogenic pneumomediastinum. Although spontaneous pneumomediastinum is usually observed in healthy young men, traumatic pneumomediastinum may be caused by blunt or penetrating trauma to the chest and neck. Pneumomediastinum is a clinical condition with potential complications that cause high morbidity and mortality rates. Pneumomediastinum also may develop without tracheal or oesophageal injury after spontaneous or blunt chest, neck and facial injuries, and it may be accompanied by pneumothorax. We treated two patients who had pneumomediastinum. Case 1 was a 20-year-old man who had pain and dyspnoea around the sternum for one hour, as a result of a blow from an elbow during a football match. Case 2 was a 23-year-old man who had a two-day history of dyspnoea and chest pain with no history of trauma. In both patients, diagnosis of pneumomediastinum was confirmed with thoracic computed tomography scans, and the condition resolved within five days of in-patient observation. In conclusion, the diagnosis of pneumomediastinum should be considered for all patients who present to the emergency department with chest pain and dyspnoea.
The effects of antioxidants on blood Gas Parameters in the acute organic phosphorus toxicity of rabbits
(ELSEVIER IRELAND LTD, 2008) Bayir, Aysegul; Kara, Hasan; Yildiz, Mesut; Ak, Ahmet; Kara, Fatih
[Abstract not Available]
Effects of Hypertonic Saline, HAES and Dymethylsulphoxyde on Free Oxygen Radicals in Haemorrhagic Shock
(2003) Bayır, Ayşegül; Kafalı, Mehmet Ertuğrul; Ak, Ahmet; Şahin, Mustafa; Karagözoğlu, Emrah; Gül, Mehmet; Karabulut, Kaan
Amaç: Bu çalışmada amaç hemorajik flok sırasında kullanılan resusitasyon sıvılarının ve bunlara antioksidan eklenmesinin doku iskemisi üzerine etkilerini araştırmaktır. Gereç ve yöntem: Kırk adet Yeni Zelanda tipi tavşan K (kontrol), I (hipertonik salin), H (HAES) ve D (dimetilsulfoksit-DMSO) olarak dört gruba ayrıldılar. Tavşanlar karotid arter yolu ile kanatıldılar. Otuz dk. floktan sonra K grubuna sıvı resusitasyonu yapılmazken, I grubuna kanama miktarının 1.5 katı olacak şekilde %7.2’lik hipertonik salin, H grubuna kanama volümüne eşit volümde HAES %10 verildi. D grubuna ise HAES %10 ile birlikte antioksidan olarak DMSO eklendi. Sıvıların ve DMSO’nun etkisini değerlendirmek için kan, karaciğer ve ince barsak TBARS (thiobarbütürik asit reaktif maddeleri) ve laktat düzeyleri çalışıldı. Bulgular: Grupların doku ve plazma TBARS ve laktat seviyeleri birbiri ile karşılaştırılınca istatistiksel olarak anlamlı bir fark olmadığı görüldü. Sonuç: Replasman sıvılarının ve bunlara antioksidan ajan eklemenin hemorajik şokta gelişen dou iskemisini azaltmada birbirlerine üstünlüğü yoktur.
Effects of Magnesium Sulfate on Tissue Lactate and Malondialdehyde Levels in Experimental Head Trauma
(SPRINGER-VERLAG, 2001) Üstün, Mehmet Erkan; Gürbilek, Mehmet; Ak, Ahmet; Vatansev, Hüsamettin; Duman, Ateş
Objective: To determine the effects of magnesium sulfate (MgSO4) on tissue lactate and malondialdehyde (MDA) levels in rabbit brain after experimental head trauma. Design: Prospective, randomized trial. Subjects: Thirty New Zealand rabbits. Interventions: Group 1 (n = 10) was the sham operated group. Group 2 (n = 10) (untreated group) and group 3 (n = 10) received head trauma with the weight drop method. MgSO4 was administered 100 mg/kg (15%) i.v. immediately after the head trauma to group 3. Trauma was applied to one side. The non-contused side was named as "a" and the contused side as "b". Measurements: One hour after trauma, brain cortices were resected and the concentrations of lactate and MDA were determined using the spectrophotometric enzymatic and thiobarbituric acid methods. One-way ANOVA and Tukey's HSD tests were used for the evaluation of the results. P < 0.05 was considered as significant. Pearson's correlation test was used between lactate and MDA levels (P < 0.001). Results: There were significant differences between MDA and lactate levels of group 1 and all other groups; non-contused (a) and contused (b) sides of groups 2 and 3; groups 2b-3a, 2b-3b (P < 0.05). The difference in MDA levels was significant between groups 2a-3b (P < 0.05). Correlation between lactate and MDA was very good in group 1, and excellent in groups 2a, 2b, 3a, and 3b. Conclusions: These results demonstrate that head trauma leads to an increase in brain tissue lactate and MDA levels, and MgSO4 suppresses the rise in contused tissue when given after head trauma.
The effects of mannitol and melatonin on MRI findings in an animal model of traumatic brain edema
(SPRINGER HEIDELBERG, 2008) Bayir, Ayseguel; Kiresi, Demet Aydogdu; Kara, Hasan; Cengiz, Sahika Liva; Kocak, Sedat; Oezdinc, Serife; Ak, Ahmet
Objectives: The aim of this study was to compare the effects of mannitol and melatonin on brain edema secondary to trauma using magnetic resonance imaging (MRI). Methods : A mild traumatic brain injury with the Feeney method was performed upon twelve New Zealand rabbits. Three hours after the trauma was inflicted, MRI images were obtained, then the subjects were divided into two groups : a mannitol group and a melatonin group. The mannitol group (n = 6) was given 2 gr/kg of 20% mannitol IV over 10 minutes and the melatonin group (n = 6) received 100 mg/kg of melatonin IV over 30 minutes. Thirty-three hours after the first MRI, MRI was repeated. The 3-hour and 36-hour post-trauma MRI images in both groups were scored regarding signs of edema and extent of brain tissue protrusion in a blinded fashion by a staff radiologist. Intragroup and intergroup comparisons were made using the Fisher exact test and chi square test. Comparison of brain tissue protrusion measurements was done using the Mann Whitney U test. Results : Signs of raised intraventricular pressure, contusion and parenchymal edema were more prevelant, and parenchymal protrusion was more prominent on the 36-hour MRI in both mannitol and melatonin groups. No significant difference was,found between the melatonin and mannitol groups in any parameter in the MRI images performed 3 and 36 hours after the head trauma. Conclusions : In this animal model, melatonin and mannitol had similar effects on brain edema, as demonstrated on MRI 3 and 36 hours after head trauma.
The effects of melatonin on oxidative stress markers in an animal model of radiocontrast-induced nephropathy
(ALLIED ACAD, 2011) Bayir, Aysegul; Kara, Hasan; Kiyici, Aysel; Kiyici, Halil; Ak, Ahmet
We investigated the effects of melatonin on erythrocyte and renal tissue superoxide dismutase (SOD) and malondialdehyde (MDA) levels in rabbits after the administration of a radiocontrast agent. Twenty-four New Zealand rabbits were divided into four groups, six rabbits in each: control, sham, hydration, and hydration plus melatonin. Rabbits in the control group were sacrificed after the extraction of renal tissue. All other rabbits received a single dose of IV diatrizoat sodium (10 mL/kg). In the hydration group, saline (10 mL/kg IV) was infused at 6 hour intervals. In the hydration plus melatonin group, melatonin (10 mg/kg IV) and saline (10 ml/kg IV) were administered at 6 hour intervals. Venous blood samples were obtained from the rabbits before, and 48 and 72 hours after diatrizoat sodium administration to measure serum urea, creatinine, sodium, potassium, calcium, and erythrocyte MDA levels and SOD activities. Renal tissues were removed at the end of 72 hours, and tissue MDA levels and SOD activities were determined. At 72 hours, erythrocyte MDA concentrations of the hydration plus melatonin animals were significantly lower than those of the sham and hydration groups. However, erythrocyte and renal tissue SOD activities were significantly higher in the hydration plus melatonin group than the other groups. Renal tissue MDA levels of the hydration plus melatonin group were significantly lower than those of the sham and hydration groups. Melatonin has favorable effects on lipid peroxidation and antioxidant status in this animal model of radiocontrast nephropathy.
Effects of Nimodipine and Magnesium Sulfate on Endogenous Antioxidant Levels in Brain Tissue After Experimental Head Trauma
(LIPPINCOTT WILLIAMS & WILKINS, 2001) Üstün, Mehmet Erkan; Duman, Ateş; Öğün, Cemile Öztin; Vatansev, Hüsamettin; Ak, Ahmet
To examine the effects of calcium antagonists nimodipine and magnesium sulfate (MgSO4) on tissue endogenous antioxidant levels, the authors studied superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels in rabbit brain 1 hour after experimental head trauma. Forty New Zealand rabbits were anesthetized and randomly divided into four groups. Group 1 (n = 10) was the sham operated group. Group 2 (n = 10), the control group, received head trauma and no treatment. Group 3 (n = 10) received head trauma and intravenous (IV) 2 mu gr/kg nimodipine. Group 4 (n = 10) received head trauma and IV 100 mg/kg MgSO4. Head trauma was delivered by performing a craniectomy over the right hemisphere and dropping a weight of 20 g from a height of 40 cm. In the right (traumatized) hemisphere, SOD and GPx decreased by 57.60% +/- 9.60% and 72.93% +/- 5.51% respectively from sham values. Magnesium sulfate, but not nimodipine, reduced the magnitude of decrease of SOD and GPx to 19.43% +/- 7.15% and 39.01% +/- 7.92% respectively from sham values. In the left (nontraumatized) hemisphere, MgSO4 increased SOD to 42.43% +/- 24.76% above sham values. The authors conclude that MgSO4 treatment inhibited the decrease in SOD and GPx levels in experimental brain injury.
Fibrinolytic markers and neurologic outcome in traumatic brain injury
(NEUROL SOC INDIA, 2006) Bayir, Aysegul; Kalkan, Erdal; Kocak, Sedat; Ak, Ahmet; Cander, Basar; Bodur, Said
Aims: To determine the usefulness of fibrinolytic markers as early prognostic indicators in patients with isolated head trauma. Materials and Methods: Sixty-two consecutive patients (26 women and 36 men; mean age 61 years, range 2-76 years) with isolated head trauma seen within the first three hours of the trauma were included in the study. The Glasgow Coma score (GCS), platelet counts (Plt), prothrombin time (PT), partial thromboplastin time (PTT), fibrinogen, fibrin degradation products (FDP) and D-dimer levels were measured. Head computerized tomography (CT) findings were categorized as brain edema, linear fracture, depressed fracture, contusion and bleeding. Plt counts, PT, PTT, fibrinogen, FDP, D-dimer levels and CT findings were compared with both GCS and mortality in the first week. Statistical significance was accepted at P <= 0.05. Results: A marked negative relationship was found between GCS and PT, PTT, FDP and D-climer levels (P < 0.001). Plt levels did not correlate with GCS. Mortality was most strongly related to GCS, PT, FDP and D-dimer levels (P < 0.001, P < 0.001, P < 0.001 and P < 0.001, respectively). We found no relationship between mortality and CT findings, nor was there any significant relationship between Plt, PTT and fibrinogen levels. Conclusion: GCS and fibrinolytic markers measured within the first three hours were useful in determining the prognosis of patients with isolated head trauma.
Geçici iskemik atak ve akut istemik inmeli hastalarda hematolojik parametrelerin karşılaştırılması
(2004) Ak, Ahmet; Bayır, Akçay Ayşegül; Gül, Mehmet; Girişgin, Sadık; Koçak, Sedat
Amaç: Bu çalışmanın amacı geçici iskemik atak (GİA) ve akut iskemik inme (Aİİ) hastalarında bazı hematolojik parametreleri karşılaştırmak ve bu parametrelerdeki değişiklikleri saptamaktır. Yöntem: Akut serebral iskemi semptomlarıyla müracat eden hastaların nörolojik ve laboratuar değerlendirilmesi yapıldı. Tanısı kesinleşen 94 Aİİ’li ve 70 GİA’lı hasta çalışmaya alındı. Kontrol grubu nörolojik semptom ve bulgu vermeyen, değişik şikayetlerle acil servise müracat eden, yaş ve cinsiyet olarak uygun 72 hastadan oluştu. Serebral iskemi semptomlarının başlangıcından itibaren 72 saat içinde müracaat eden bütün hastalardan kabulden hemen sonra kan alındı. Alınan kan örneklerinden BK, Trombosit, fibrinojen, sedimantasyon değerleri saptandı ve elde edilen değerlerin gruplar arası karşılaştırılması yapıldı. Bulgular: Trombosit sayısı GİA ve Aİİ gruplarında kontrol grubuna göre yüksek olarak bulundu (p0,001). Fibrinojen seviyesi, lökosit sayısı ve sedimantasyon Aİİ’li hastalarda hem kontrol hem de GİA grubuna göre yüksekti (p0,001). Sonuç: Sonuçlarımız, bazı hematolojik parametrelerin (özellikle lökosit sayısı, fibrinojen ve sedimantasyon) spesifik olmamakla birlikte özellikle akut iskemik inmenin habercisi olabileceğini desteklemektedir.

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