Network


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

Hotspot


Dive into the research topics where Hülya Akgün is active.

Publication


Featured researches published by Hülya Akgün.


World Journal of Surgery | 2006

Granulomatous Lobular Mastitis: A Complex Diagnostic and Therapeutic Problem

Alper Akcan; Hizir Akyildiz; Mehmet Ali Deneme; Hülya Akgün; Yucel Aritas

BackgroundGranulomatous lobular mastitis is a rare chronic inflammatory disease of the breast. Clinical and radiological features may mimic breast carcinoma. Since this entity was first described, several clinical and pathologic features of the disease have been reported, but diagnostic features and treatment alternatives are still unclear. The purpose of this study is to evaluate diagnostic difficulties and discuss the outcome of surgical treatment in a series of 21 patients with granulomatous lobular mastitis.MethodsA retrospective review of 21 patients with histologically confirmed granulomatous lobular mastitis treated in our center between January 1995 and May 2005 was analyzed to identify issues in the diagnosis and treatment of this rare condition.ResultsThe most common presenting symptoms were a mass in the breast and pain. Four patients had no significant mammographic findings (MMG), but on ultrasound (US), 2 had irregular hypoechoic mass, and 2 hypoechoic nodular structures had abnormalities—one parenchymal distortion and 1 mass formation in 2 of these 4 patients’ magnetic resonance imaging (MRI). In recurrent cases, limited excision under local anesthesia was performed, as the clinical examination suggested carcinoma.ConclusionsAlthough some findings on MMG and US are suggestive of benign breast disease, these modalities do not rule out malignancy. MRI may be helpful in patients who do not have significant pathology at MMG or US. Fine-needle aspiration cytology may be useful in some cases but diagnosis is potentially difficult because of its cytologic characteristics. Wide excision, particularly under general anesthesia, can be therapeutic as well as useful in providing an exact diagnosis.


Respiration | 2005

Bronchiolitis obliterans Organizing Pneumonia

F. Sema Oymak; H. Murat Demirbaş; Ertugrul Mavili; Hülya Akgün; Inci Gulmez; Ramazan Demir; Mustafa Özesmi

Background: Bronchiolitis obliterans organizing pneumonia (BOOP) may be classified as cryptogenic (idiopathic) and secondary. There are no clear clinical and radiological features distinguishing between idiopathic and secondary BOOP. Objectives: To analyze the etiologic factors, clinical and radiological features, diagnostic approach and response to therapy at onset and outcome in subjects with BOOP. Methods: The medical files of Erciyes University Hospital from 1995 to 2003 were retrospectively reviewed. Patients with biopsy-proven BOOP were selected for evaluation. The etiology and initial features of BOOP, treatment, resolution, relapse, and survival were obtained from medical records, and a follow-up patient questionnaire. Results: We have diagnosed 26 cases (13 males /13 females) with BOOP syndrome (mean age 54 ± 15 years, range 14–93). More than half the patients (58%) were classified as idiopathic BOOP. Patients presented with cough (92%), dyspnea (70%), pleuritic chest pain, hemoptysis and fever (50%). The biopsy specimens had been obtained by transbronchial and/or transthoracic lung biopsy in 18 cases (69%). At radiological evaluation, there were bilateral patchy alveolar and/or interstitial infiltrates in 16 patients (62%), and solitary pneumonic involvement in 10 patients (38%). Three patients recovered spontaneously, 5 remained cured after resection of the focal lesion. Corticosteroid therapy was given in 17 patients (65%). Apart from four patients who died (death was attributable to BOOP in only 1 patient) and three patients who relapsed, the prognosis was good in all patients. Conclusions: The etiology of BOOP is usually idiopathic. We observed that hemoptysis and pleuritic chest pain were a relatively frequent symptom in BOOP in the present series, in contrast to previous observations. The diversity of radiological and clinical presentations including hemotysis and pleuritic chest pain should prompt consideration of the diagnosis in patients with persisting pulmonary symptoms and radiological findings.


Annals of Nutrition and Metabolism | 2003

Use of Olive Oil Based Emulsions as an Alternative to Soybean Oil Based Emulsions in Total Parenteral Nutrition and Their Effects on Liver Regeneration following Hepatic Resection in Rats

Engin Ok; Zeki Yilmaz; İnci Karaküçük; Hülya Akgün; Habibe Şahin

Background/Aim: The main objective of this study was to compare the effects of olive oil to those of soybean oil on liver tissue regeneration following hepatic resection in rats. Methods: Seventy albino Wistar rats were randomly assigned to seven groups which contained 10 rats each. Group 1 was the sham-treated group; groups 2 and 3 received total parenteral nutrition (TPN) containing soybean oil lipid emulsions (20% Lipofundin MCT/LCT) for 48 or 72 h; groups 4 and 5 received TPN containing olive oil (80%)/soybean oil (20%) lipid emulsions (ClinOleic 20%) for 48 or 72 h; group 6 was the control group for 48 h, and group 7 was the control group for 72 h. TPN was given via internal jugular vein, and 70% hepatic resection was performed in the study groups. In addition, hepatic resections with no TPN were performed in the control groups, except the sham group. Relative liver weight, mitotic index, proliferating cell nuclear antigen labeling index, and carnitine levels in liver tissue samples were used to assess hepatic regeneration. Thiobarbituric acid reactive substances were measured as an index of lipid peroxidation and oxidative tissue damage. Alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase were parameters for the liver function. Results: The relative liver weight increased significantly with minimal hepatosteatosis in the olive oil treated groups. Lipid peroxidation significantly decreased with near-normal serum levels of the liver function parameters in the olive oil/soybean oil treated groups, and mitotic index and proliferating cell nuclear antigen labeling index reached their maximum level in rats receiving TPN containing any kind of lipid emulsions for 48 h following resection. Conclusions: The use of olive oil/soybean oil lipid emulsions in TPN has important beneficial effects on the liver regeneration, and the antioxidant properties of olive oil originating from its natural components indirectly contribute to the liver regeneration in rats.


British Journal of Ophthalmology | 2014

Overexpression of vascular endothelial growth factor receptor 2 in pterygia may have a predictive value for a higher postoperative recurrence rate

Koray Gumus; Sarper Karakucuk; G. Ertugrul Mirza; Hülya Akgün; Hatice Arda; Ayse Oner

Background To investigate the expression levels of vascular endothelial growth factor (VEGF), vascular endothelial growth factor receptor 1 (VEGFR-1) and VEGFR-2 in pterygium and to clarify the prognostic significance of these expressions in pterygia. Methods A total of 40 surgically excised pterygia and 9 normal conjunctivae were immunohistochemically studied applying the streptavidin–biotin method in paraffin-embedded tissue sections. Monoclonal antibodies were targeted against VEGF, VEGFR-1 and VEGFR-2 proteins. At the sixth postoperative month, the recurrence rate was graded on a scale of 1–4. Results The mean percentage of VEGF-positive epithelial cells was comparable in pterygium and normal conjunctivae. However, the pterygium group presented higher expression levels of VEGF in pterygia endothelial cells (p=0.05). In terms of VEGFR-1 expression in epithelial cells, no statistically significant difference was found between two groups (p=0.658). However, normal conjunctivae exhibited higher expression levels of VEGFR-1 in endothelial cells (p=0.002). Epithelial cells in pterygium presented higher combined scores of VEGFR-2 (87.5% and 22.2%, respectively) (p=0.013). While higher expression levels of VEGFR-2 were documented in pterygia endothelial cells, no VEGFR-2 immunoreactivity was observed in the endothelial cells of normal conjunctivae (p<0.001). Expression levels of VEGFR-2 in epithelial cells and endothelial cells were positively correlated with the postoperative recurrence grading system (p<0.001 and τ=0.627, p=0.001 and τ=0.508, respectively). Conclusions The results suggest that VEGF may play a key role through VEGFR-2 in the pathogenesis of pterygium. Moreover, overexpression of VEGFR-2 in pterygia may have a predictive value for a higher postoperative recurrence rate.


Yonsei Medical Journal | 2008

The Effect of High Dose Melatonin on Cardiac Ischemia-reperfusion Injury.

Hakan Ceyran; Figen Narin; Nazmi Narin; Hülya Akgün; A. Bahar Ceyran; Figen Öztürk; Yiğit Akçali

Purpose Melatonin, the most potent scavenger of toxic free radicals, has been found to be effective in protecting against pathological states due to the release of reactive oxygen species. This study was performed to establish the effect of high dose melatonin on protection against ischemia-reperfusion (I/R) injury in rat hearts. Materials and Methods Forty male Sprague-Dawley rats were used in this study. They were separated into four groups of ten rats each. A left coronary artery occlusion was induced in the rats by ligating the artery for 20 minutes and then releasing the ligation (reperfusion) afterwards. The control group was Group A. Group B was subjected to myocardial ischemia-reperfusion without any treatment, while Group C underwent myocardial ischemia-reperfusion with a melatonin treatment before the ischemia. Group D was subjected to myocardial ischemia-reperfusion with a melatonin treatment before the reperfusion. After 20 minutes of reperfusion, blood samples were obtained from each group for biochemical studies, and the animals were sacrificed for histological and, immunohistochemical examinations of the myocardial tissue. Results We found that the cardiac troponin T(cTn-T) levels were significantly increased in Group B when all groups were compared. In the Group C rats treated with melatonin, the cTn-T values were significantly lower than those in Groups B and D. In addition, malondialdehyde (MDA) and antioxidant enzymes including, superoxide dismutase (SOD) and myeloperoxidase (MPO) were lower than those in Group B in the melatonin treated groups. The differences were statistically significant (p < 0.05). Histopathologic and immunohistopathologic studies also supported the effectiveness of melatonin. Conclusion Our study suggests that high dose melatonin, appears to offer protection against cardiac ischemia-reperfusion injuries in rats by scavenging the free radicals and could have a potential clinical use in the management of myocardial ischemia.


Regulatory Peptides | 2005

Renal effects of long-term leptin infusion and preventive role of losartan treatment in rats

Zübeyde Gündüz; Nurcan Dursun; Hülya Akgün; Figen Öztürk; Hamit Okur; Nedret Koç

BACKGROUND Leptin has direct and indirect effects on renal pathophysiological characteristics. In the present study, the effects of long-term leptin infusion on the renal hemodynamics, renal excretory functions, and the expression of transforming growth factor-beta (TGF-beta), plasma endothelin-1 (ET-1) levels, and preventive effects of the angiotensin II type 1 receptor antagonist, losartan, on these renal changes were evaluated. METHODS The study was performed by using forty Wistar albino rats. On day 0, osmotic mini-pumps filled with leptin or placebo were intraperitoneally placed under sterile conditions. The rats in Group L (Leptin group, n=15) and Group LL (Leptin-losartan group, n=15) were given recombinant murine leptin at a rate of 250 ng per hour for 28 days. Control rats (Group C, n=10) were administered placebo at the same infusion rate. The rats in Group LL were also administered losartan (10 mg kg(-1) d(-1)) perorally for 28 days. On day 28, the rats were placed in metabolic cages, and the food and water intakes were determined, and the urine was collected for 24 h. At the end of the study, systolic blood pressure (SBP), diastolic blood pressure (DBP) were determined directly from the left femoral artery, and renal blood flow (RBF) was recorded indirectly using a laser Doppler flow module. RESULTS Leptin infusion did not produce any changes in systemic arterial blood pressures and urinary flow rate. The rates of creatinine (Cr), sodium (Na), and protein excretions of the animals infused leptin were significantly increased. The urinary Cr and Na excretions were decreased, while the urinary protein excretion was normalized with the losartan treatment. The rats infused leptin had also higher circulating ET-1 levels. ET-1 levels were also reversed to the normal values with the losartan treatment. Renal TGF-beta1 expression was determined immunohistochemically, and it was more prominent in the renal tubules from the rats treated with leptin. The losartan treatment had no effect on renal TGF-beta1 expression. CONCLUSIONS Our results indicate that pathophysiological increases in plasma leptin concentrations cause enhanced renal Na, Cr and protein excretions, and high circulating ET-1 levels. Na and Cr excretions were decreased, while proteinuria and plasma ET-1 levels were normalized by losartan treatment, suggesting that renin-angiotensin system activation may have a role in leptin induced renal changes. TGF-beta1 may have an important role in leptin induced nephropathy.


Journal of Clinical Ultrasound | 2009

Prenatal sonographic findings in a fetus with splenogonadal fusion limb defect syndrome

M. Basbug; Hülya Akgün; Mahmut Tuncay Ozgun; Cagdas Turkyilmaz; Cem Batukan; Bülent Özçelik

Splenogonadal fusion limb defect syndrome (SGFLD) is a very rare abnormality. We report on a case with prenatal sonographic findings of a fetus with postnatally diagnosed SGFLD syndrome. This is also the second case of prenatal ultrasonographic diagnosis of gastrointestinal malrotation associated with SGFLD. A 26‐year‐old primigravid woman was referred to our clinic because of nonvisualization of both fetal femoral bones at 20 weeks of gestation. A detailed sonographic examination showed complete bilateral absence of lower limbs, micrognathia, single umbilical artery and a right‐sided stomach. Autopsy confirmed prenatal sonographic findings and additionally showed that the spleen was abnormally connected to the left gonad by a fibrous band. In conclusion, although all limbs and both sides were equally affected in most of the reported cases, SGFLD syndrome should be considered in cases with terminal limb defects of lower limbs.


Computer Methods and Programs in Biomedicine | 2013

Performance comparison of machine learning methods for prognosis of hormone receptor status in breast cancer tissue samples

Adem Kalinli; Fatih Sarikoc; Hülya Akgün; Figen Öztürk

We examined the classification and prognostic scoring performances of several computer methods on different feature sets to obtain objective and reproducible analysis of estrogen receptor status in breast cancer tissue samples. Radial basis function network, k-nearest neighborhood search, support vector machines, naive bayes, functional trees, and k-means clustering algorithm were applied to the test datasets. Several features were employed and the classification accuracies of each method for these features were examined. The assessment results of the methods on test images were also experimentally compared with those of two experts. According to the results of our experimental work, a combination of functional trees and the naive bayes classifier gave the best prognostic scores indicating very good kappa agreement values (κ=0.899 and κ=0.949, p<0.001) with the experts. This combination also gave the best dichotomization rate (96.3%) for assessment of estrogen receptor status. Wavelet color features provided better classification accuracy than Laws texture energy and co-occurrence matrix features.


Brain & Development | 2006

Calcified chronic subdural hematoma mimicking calvarial mass : A case report

Hüseyin Per; Hakan Gumus; Bülent Tucer; Hülya Akgün; Ali Kurtsoy

Head trauma is a frequent cause of mortality and morbidity in the pediatric population. Chronic subdural hematoma is the most common traumatic lesion in head injury. Chronic subdural hematomas are rare in children older than 2 years old; they are more frequent during adolescence. Calcified or ossified chronic subdural hematoma is a rare entity that usually presents as a space-occupying lesion over the cerebral convexity. Chronic calcified subdural hematomas are reported less than chronic subdural hematomas. In this article, we report a successfully treated patient with surgical removal case of calcified chronic subdural hematoma mimicking calvarial mass.


Journal of Surgical Research | 2009

Effects of amrinone in an experimental model of hepatic ischemia-reperfusion injury.

Can Kucuk; Alper Akcan; Hizi Akyýldýz; Hülya Akgün; Sebahattin Muhtaroglu; Erdoğan Sözüer

BACKGROUND During some surgical interventions, temporary occlusion of the hepatic blood supply may cause ischemia-reperfusion (IR) injury. Recent studies suggest that type 3 phosphodiesterase inhibitors may have a beneficial effect on liver IR injury. The aim of this study was to investigate whether amrinone, a type 3 phosphodiesterase inhibitor, could have a protective effect on liver having experimental liver IR injury. MATERIALS AND METHODS Sixty Wistar albino rats were randomly divided into three groups. The IR and amrinone groups were subjected to 1 h total hepatic ischemia, followed by 2 h of reperfusion. The sham group underwent midline laparotomy only. Amrinone 10 microg/kg/min was infused to the amrinone group during the 3 h of the IR period. Histopathological examination, biochemical liver function, and liver adenosine triphosphate concentration after reperfusion and survival rate on the seventh day after the IR insult were recorded. RESULTS Serum aspartate aminotransferase, alanine aminotransferase, lactic dehydrogenase levels, and histological damage scores in the amrinone and IR groups were significantly higher compared with the sham group (P < 0.01). However, all of these values were significantly lower in the amrinone group than in the IR group (P < 0.05). Liver adenosine triphosphate levels and the rat survival rate in the amrinone and IR groups were significantly lower than those in the sham group (P < 0.01). However, these values were significantly higher in the amrinone group compared to those in the IR group (P < 0.01). CONCLUSIONS These results suggest that amrinone plays a significant role in the protection of liver against IR injury and that this treatment may be a novel pharmacological agent for safe and efficient liver surgery.

Collaboration


Dive into the Hülya Akgün's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge