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Öğe Atık baca gazından elektrik enerjisi üretimi ve ısı değiştiricisi tasarımı(Hitit Üniversitesi, 2024) Şahin, Mustafa; Seyitoğlu, ÜyesiTeknolojinin gelişmesi ve artan nüfus enerjiye olan bağımlılığı arttırmaktadır. Ülkemiz enerji ithalatçısı ülkelerden biri olduğundan enerjinin verimli kullanılması önemlidir. Bu bağlamda enerji tüketiminin fazla olduğu yerlerde enerji verimliliğine yönelik çalışmaların yapılması gerekmektedir. Bu çalışmanın temel amacı enerji tüketimi yüksek olan bir işletmenin ürettiği atık baca gazını işletme içerisinde faydalı işe dönüştürerek verimliliğe ve çevreye olan etkisini ortaya koymaktır. Bu kapsamda Merzifon Organize Sanayi Bölgesinde yer alan metal sektöründe faaliyet gösteren bir işletme hedef alınarak analizler yapılmıştır. Firma bünyesinde bulunan tav fırınından çevreye salınan baca gazı ile ilgili çalışmalar yapıldı. Firmada bulunan tav fırınının baca gazı verileri firma içerisinde yapılan ölçümlerle elde edilmiştir. Atık baca gazının debisi 28.229,1 m3/saat, çıkış sıcaklığı ise 122,36 °C olarak ölçülmüştür. Elde edilen veriler ışığında baca kesitine uygun ısı değiştirici tasarımı yapılmış ve daha sonra baca gazı sıcaklığından elektrik üretecek bir sistem tasarımı yapılmıştır. Tasarım çalışmasında firma bünyesinde bacada kullanılacak ısı değiştiricisi gövde-borulu ısı değiştiricisi olarak belirlendi. Sistemde baca gazı sıcaklığından elektrik üretimi için Organik Rankine Çevriminin kullanılması öngörülmektedir. Çalışmada mühendislik çözümleri için yaygın olarak kullanılan Engineering Equation Solver (EES) paket programı kullanılmıştır. Çalışmada R290, R245fa, R134a, R600, R1234yf ve R1234ze soğutucu akışkanları için ayrı ayrı hesaplamalar yapılmıştır. Altı farklı akışkan için termodinamik ve ekonomik analizler yapıldı. Sonuç olarak tasarlanan sistem sonucunda maksimum 42,796 kW elektrik enerjisi üretilebileceği gösterilmiştir. Ayrıca sistemin geri ödeme süresi 3 yıl 3 ay olarak hesaplanmıştır.Öğe Bladder stone secondary to prolene suture after gynecologic surgery(NLM (Medline), 2018) Sungur, Mustafa; Çalışkan, Selahattin; Lokman, Utku; Savcı, Ünsal; Şahin, MustafaBladder stones are usually seen among patients with bladder outlet obstruction, especially in men over the age of 50 years. There are several risk factors for bladder stones, including urinary tract infections, abnormal urinary tract system anatomy, and presence of foreign bodies. In addition, migrating intrauterine contraceptive devices through the wall of the urinary bladder and foreign bodies such as surgical sutures may act as a nidus for developing stone formation. Here in, we report a case of bladder stone associated with surgical non-absorbable suture, used for gynecologic surgery 4 years ago, and treated endoscopically. The aim of this paper was to know gynecological association and the management of bladder stones. The patients who had a history of pelvic surgery previously and present with lower urinary tract symptoms such as dysuria, voiding difficulties, weak micturition and hematuria should be evaluated for the foreign body-associated disorders.Öğe Böbrek transplantasyonunda ‘97 Banff sınıflandırmasının klinik ve biyokimyasal parametrelerle karşılaştırılması - Banff 2017 sınıflandırması ile hangi kriterler değişti?(2018) Baş, Yılmaz; Şahin, MustafaAmaç: Çalışmamızda, böbrek nakli yapılan olgularda reddetme tipleri, biyokimyasal bulgular, tedaviye yanıt ve prognozla ilişki araştırıldı. Banff ‘97 sınıflandırmasından 2017 sınıflandırmasına kadar değişen kriterler tartışıldı. Yöntem: Ocak 1991-2000 yılları arasında akut rejeksiyon tanısı almış 86 olguya ait68 biyopsi Banff kriterlerine göre değerlendirildi. Biyopsiler, ilk tanılarına ve Banff kriterlerine göre Akut Hücresel Rejeksiyon (AHR), Borderline değişiklik (BD) ve Kronik Allogreft Nefropati (KAN) olarak üç gruba ayrıldı. Tedaviye yanıt, tedavi sonrası serum kreatinin (SCr)/baseline SCr oranı kullanılarak değerlendirildi. Rejeksiyon dereceleri interval, biyopsi anındaki SCr düzeyi, delta kreatinin, proteinüri değeri ile karşılaştırıldı. Bulgular: Çalışmaya dâhil edilen 168 biyopsiden 92’i (%54.7) akut rejeksiyon tanısı aldı. Örneklerin 34’ü saf AHR, 31’i BD, 17’si KAN tanısı aldı. Akut rejeksiyon tanısı alan olgularda rejeksiyon tipi ve biyopsi sonrası tedaviye yanıt arasında istatistiksel olarak anlamlı fark bulunmadı (p>0.05). BD olgularında biyopsi öncesi ve tedavi sonrası SCr düzeylerinde arasında istatistiksel olarak anlamlı fark vardı (p<0.001). Proteinüri ile grade ve KAN arasında istatistiksel olarak ilişki bulunmadı (p>0.05). Greft süresi, SCr seviyesi, Delta kreatinin arasında istatistiksel olarak anlamlı fark vardı, (sırasıyla; p<0.001, p<0.05, p<0.005). Greft kaybı 28 (%16.7) olguda, 213 ile 4836 gün (ortalama 1330) arasında gerçekleşti. Sonuç: Banff ‘97 sınıflandırmasında yapılan akut ve kronik lezyon skorlarındaki kriterler ile çalışmamızdaki bulgular uyumlu bulunmuştur. Banff 2017 sınıflandırmasının temelini oluşturan Banff ‘97 sınıflandırmasının, ret dönüşünü öngörmede çok önemli olan spesifik histolojik yarı-kantitatif parametreleri doğrulanmıştır. Banff 2017 sınıflandırmasında genetik ve moleküler yöntemlerin eklenmesiyle, böbrek allogreft histomorfolojisinde son kriterlerin daha da özelleştiği görülmüştür.Öğe Comparison of the effectiveness of screening methods for the diagnosis of gestational diabetes mellitus in pregnant women: A cross-sectional study(Wiley, 2021) Şahin, Mustafa; Görkem, Ümit; Bilgi, Ahmet; Dikker, OkanObjective The methods and criteria used for gestational diabetes mellitus (GDM) screening in pregnant women are updated by the relevant organisations in certain periods. We aimed to compare the efficiency of GDM screening tests in pregnant women and to investigate the reasons of different prevalence values reported in the literature. Materials and Methods In this retrospective cross-sectional study, a total of 2406 pregnant women who were admitted to the obstetric outpatient clinic for screening GDM, were included. All pregnant women were randomly screened between 24 and 28 gestational weeks, using one-step (75 gr glucose loading) or two-step (50 gr and 100 gr glucose loading) methods. The demographic, clinical and biochemical parameters of the study population were analysed. Results In our study, 680 pregnant women were screened by one-step method and 1726 by two-step method. The average age of the one-step and two-step groups was 28.3 +/- 5.7 and 28.1 +/- 5.1, respectively, and no statistically significant difference was found between the ages of the two groups (P = .647). Other baseline characteristics, including maternal age, maternal weight, height, body mass index, gestational week, multiparity, systolic blood pressure, diastolic blood pressure, pulse, fasting plasma glucose were not significantly different between the two groups (P > .05, for all). The prevalence of GDM was significantly higher in the one-step group than that in the two-step group: 158/680 (23.2%) versus 143/1683 (8.5%), respectively. A statistically significant difference was found between the prevalence of the two groups (P < .001). Conclusion The reason for the different prevalence values obtained in GDM screening studies may be because of the preferred method. Considering the advantages and disadvantages of both methods, studies are needed in which international organisations will revise their diagnostic criteria. We think it would be more appropriate to use the two-step screening method until international professional organisations develop a new methodology and new cut-off values.Öğe In vitro bactericidal effect of Ho:YAG laser and pneumatic lithotripsy on ureteral stones colonized with Escherichia coli and Enterococcus faecalis(Springer Verlag, 2019) Savcı, Ünsal; Sungur, Mustafa; Şahin, Mustafa; Eser, Barış; Çalışkan, SelahattinThe endoscopic treatment of urolithiasis has a high success rate and the complications decreased after the development of lithotripsy techniques. The aim of this study is to investigate the in vitro bactericidal effect of laser and pneumatic lithotripsy on urinary stones colonized with Escherichia coli and Enterococcus faecalis. A total of 40 natural calcium oxalate stones, which were obtained from the patients’ urinary systems with rigid ureteroscopy were used in the study. Surfaces of the stones were colonized with E. coli and E. faecalis strains. The fragmentation of the stones was performed using holmium:yttrium-aluminum-garnet laser (Ho:YAG laser) and pneumatic lithotripters in vitro in Eppendorf tubes filled with liquid. After fragmentation, samples taken from Eppendorf tubes were inoculated on blood and EMB agar. The number of colonies was evaluated after 18–24-hour incubation period. The laser lithotripsy technique reduced the number of colonies by 100% and had bactericidal effect on E. coli and E. faecalis. Pneumatic lithotripsy technique had no bactericidal effect on these strains (0%). In the fifth minute of laser irradiation, the average temperature in the Eppendorf tube was 51–55 °C, and the average temperature in the tenth minute was 54–60 °C. The temperatures did not change in the fifth and tenth minutes with the pneumatic lithotripsy procedure. The present study revealed the bactericidal effect of Ho:YAG laser on E. coli and E. faecalis in vitro. Increased ambient temperature during Ho:YAG laser lithotripsy is thought to play a role in the bactericidal effect. But the question of whether an ideal lithotripter efficiently inactivates or destroys bacteria has still not been answered in urology practice. This preliminary study showed the bactericidal effect of Ho:YAG laser lithotripsy, but further studies are needed to investigate the bactericidal effect of Ho:YAG laser in vivo. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.Öğe Investigation of Superior Laryngeal Nerve Disorders with Laryngeal Electromyography in Patients with Hoarseness(2019) Öğreden, Şahin; Kaytaz, Asım; Öz, Ferhan; Uzun Adatepe, Nurten; Şahin, MustafaIntroduction: In this study, we aimed to investigate the laryngeal electromyography (L-EMG) findings of organic and functional laryngeal pathologies that affect superior laryngeal nerve in patients with hoarseness. Methods: All patients underwent routine examination and videolaryngoscopy using a 70-degree 4-mm telescope. L-EMG studies were performed via portable Dantec™ Keypoint® EMG/ NCS/EP Workstation with 2-channel options. For EMG, 20 mm bipolar concentric needle electrodes were used. Because the procedure was relatively painless and local anesthetics could affect the function of the muscles, no local anesthesia was administered to the patients. Cricothyroid muscle (CTM) and thyroarytenoid muscle (TAM) were tested by electromyography method. Results: Twenty-four patients with hoarseness were included in the study. Eleven patients (46%) were male and 13 (54%) were female. The mean age was 37.62 years (range: 15-57 years). A total of 96 muscles were examined with EMG. L-EMG was pathological in 15 patients (62.5%) and bilateral pathology was observed in three patients. Twenty muscles (20.8%) were detected as pathological, with neurogenic involvement in 20 muscles (70%), poor activity or no activity in four muscles (20%) and dystonic activity in two muscles (10%). Eight right CTMs (five neurogenic involvement, two poor activity, one no activity) and five left CTMs (two neurogenic involvement, one poor activity, two dystonic activity) were pathological. TAMs had neurogenic involvement on the right side in four patients and on the left side in three patients. Conclusion: It should be kept in mind that L-EMG may be an adjunctive application for detecting pathologies with neurogenic or myogenic involvement that affect the superior laryngeal nerve and lead to hoarseness.Öğe Investigation of the distribution of thyroid dysfunction in the geriatric patient population in Corum province(2019) Şahin, Mustafa; Karabulut, Alpaslan; Kayadibi, HüseyinObjectives: The aim of this study was to identify and analyze the incidence of thyroid dysfunction in geriatric patients in Corum province, Turkey. Methods: The results of thyroid-stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) tests, as well as the demographic characteristics of 220 randomized patients were retrospectively investigated. Patients who had a total or partial thyroidectomy surgery and those receiving any medical thyroid treatment were not included in the study. The patients were divided into 5 groups: subclinical hypothyroidism, hypothyroidism, euthyroid, subclinical hyperthyroidism, and hyperthyroidism. Results: In the group, 114 were male and 106 were female. The mean age of the male and female patients was 74±7 years and 75±7 years, respectively. The entire study group had a median TSH of 0.94 ?IU/mL (25th-75th percentile, interquartile range [IQR] 0.33-1.86 ?IU/mL), a median FT4 of 1.14 ng/dL (IQR: 1.02-1.33 ng/dL), and a median FT3 of 2.73 pg/mL (IQR: 2.25-3.11 pg/mL). For male patients, the median TSH was 0.87 ?IU/mL (IQR: 0.36-1.66 ?IU/mL), the median FT4 was 1.14 ng/dL (IQR: 1.02-1.29 ng/dL), and the median FT3 was 2.74 pg/mL (IQR: 2.18-3.15 pg/mL), while for female patients the median TSH was 0.95 ?IU/mL (IQR: 0.20-2.21 ?IU/mL), the median FT4 was 1.17 ng/dL (IQR: 1.06-1.38 ng/ dL), and the median FT3 was 2.72 pg/mL (2.31-3.10 pg/mL). Of the males, 1.8% had subclinical hypothyroidism, another 1.8% had hypothyroidism, 72.8% were euthyroid, 19.3% had subclinical hyperthyroidism, and 4.4% had hyperthyroidism. Among the females, there were findings of 2.8% subclinical hypothyroidism, 1.9% hypothyroidism, 64.2% euthyroid, 26.4% subclinical hyperthyroidism, and 4.7% hyperthyroidism. No statistically significant difference was observed when the diagnosis incidence was compared according to gender (p=0.696). Conclusion: Independent of gender, the geriatric patient population had a high incidence of subclinical hyperthyroidism, which often has a delayed diagnosis. This can complicate the prompt diagnosis of other metabolic diseases. As thyroid function affects the metabolism of the entire body, thyroid hormone status should be investigated when considering other metabolic diseases in geriatric patients. Excluding thyroid disfunction could save time in making an accurate diagnosis and providing treatment. Furthermore, since thyroid diseases are influenced by environmental iodine, regional thyroid disease incidence studies should be performed.Öğe Letter to the Editor: Relationship between glycemic control and serum uric acid level in acute myocardial infarction(2018) Şahin, Mustafa; Savcı, Ünsal; Şahin, Havva Hande Keser[Abstract Not Available]Öğe Likit Kromatografi-Tandem Kütle Spektrometre ile 25-Hidroksivitamin D3 Ölçüm Belirsizliğinin Değerlendirilmesi(2018) Basat, Burcu; Vardar, Müberra; Dikker, Okan; Şahin, MustafaAmaç: Ölçüm belirsizliği, elde edilen test sonucunun kalitesinin kantitatif göstergesi olup, test sonucunun gerçek değeri ne ölçüde temsil ettiğini gösterir. Bu nedenle laboratuvarımızda likid kromatografi-tandem kütle spektrometre ile analizi yapılan 25 hidroksivitamin D3 testi için ölçüm belirsizliğini hesaplamayı ve hesabının nasıl yapılacağını, bulgularımızı literatürdeki diğer sonuçlarla karşılaştırmayı, belirsizlik değerinin hastaların D vitamini durumu kararına olası etkilerini değerlendirmeyi amaçladık. Gereç ve Yöntem: Likid kromatografi-tandem kütle spektrometre ile analiz edilen 25-hidroksivitamin D3 için, Nordest kılavuzu baz alınarak oluşturulan ölçüm belirsizliği hesaplama modeli doğrultusunda, bir yıllık patolojik ve normal seviyelerdeki toplam 440 adet iç kalite kontrol verileri, 4 döngü, her döngüde 5 seviye olmak üzere 20 adet dış kalite kontrol verileri kullanılıp standart belirsizlikler hesaplanarak her birinin karesi alınıp toplandı ve bu değerin karekökü alınarak birleşik belirsizlik hesaplandı. Daha sonra da birleşik belirsizlik değeri k faktörü ile çarpılararak genişletilmiş ölçüm belirsizliği elde edildi. Bulgular: Laboratuvar içi yeniden üretilebilirlik %7.44, laboratuvardan kaynaklanan bias %16.01, ölçüm prosedüründen kaynaklanan bias %0.82, bias komponentinin ölçüm belirsizliği %16.03, birleşik belirsizlik %17.67 ve genişletilmiş ölçüm belirsizliği %34.64 olarak hesaplandı. Sonuç: 25-hidroksivitamin D3 için total izin verilebilir hata +/- %25 olduğundan, çalışmamız sonucunda; 25-hidroksivitamin D3 için genişletilmiş ölçüm belirsizliği değerimiz yüksek bulunmuştur. Bu değeri %25’in altına düşürmek için olası hataları kısıtlayacak hedefe yönelik çözümler aranmalıdır. Hastanın sonuçlarına ölçüm belirsizliği deg?erini eklemek, klinik karar verme noktasında hekimin gücünü ve laboratuvar sonuçlarına olan güveni artıracaktır.Öğe Microscopic Polyangiitis Nodosa: A Rare Cause of Cerebral Hemorrhage(2019) Eser, Barış; Koyun, Osman Nuri; Doğan, İbrahim; Şahin, Mustafa; Çolak, Aysel; Özkayar, NihalMicroscopic polyangiitis nodosa (MPA) is a necrotizing vasculitis that affects small vessels, typically associated with myeloperoxidase anti-neutrophil cytoplasmic antibody. Cerebrovascular diseases are rarely reported to be associated with MPA. A 41-year-old male patient presented to the emergency room with complaints of speech difficulty and loss of strength on the left upper extremity, and MPA was detected with cerebral hemorrhage and renal failure. The case report, just as we first defined with this case in the national literature, was presented to emphasize that MPA may be rarely demonstrated with symptoms of cerebrovascular involvement except for commonly seen organ involvement.Öğe Postmenopozal Kadınlardaki Ürik Asit Düzeyinin Kemik Metabolizması Üzerine Etkisi(2019) Şahin, Mustafa; Dikker, Okan; Atar, SevgiAmaç: Östrojen düzeyindeki azalma, hücrede reaktif oksijen türlerinin birikimine ve antioksidan savunma sisteminde baskılanmaya yol açarak oksidatif stres oluşturur. Böylece osteoklastların aktivitesi ve kemik rezorbsiyonu uyarılır. Antioksidan özelliğinden dolayı ürik asitin kemik mineral yoğunluğuna (KMY) katkıda bulunabileceği belirtilmektedir. Çalışmamızda; postmenopozal dönemdeki kadınlarda serum ürik asit düzeylerinin, KMY ve diğer kemik metabolik belirteçleri ile ilişkisini araştırdık. Gereç ve Yöntem: Yaşları 50 ile 69 arasında değişen 141 postmenopozal dönemdeki kadının KMY ve laboratuvar verileri (glukoz, üre, kreatinin, kalsiyum, fosfor, alkalen fosfataz, ürik asit, paratiroid hormon ve 25-hidroksivitamin D3 düzeyleri) değerlendirildi. Katılımcılar t-skoruna göre üç gruba ayrıldı. Bunlar; <-2,5 olanlar osteoporoz hasta grubu; -2,5 ile -1,0 arasında olanlar osteopeni hasta grubu, >-1 olanlar ise normal KMY grubu idi. Biyokimyasal testler fotometrik yöntemle ölçüldü ve hormon testleri elektrokemilüminesans yöntemi ile ölçüldü. Bulgular: Ürik asit düzeyleri osteopeni grubunda normal KMY grubuna göre anlamlı olarak daha yüksekti (p=0,023). Osteoporoz-osteopeni ve osteoporoz-normal KMY grupları arasında ise ürik asit düzeylerinde istatistiksel olarak anlamlı bir fark yoktu. Tüm gruplarda ürik asit düzeyleri ile KMY arasında herhangi bir korelasyon bulunamadı. Postmenopozal osteopeni ve normal KMY grupları arasındaki ürik asit düzeylerinde negatif korelasyon bulurken (r=-0,423, p=0,016), osteoporoz ve normal KMY grupları arasında anlamlı bir fark yoktu (p>0,05). Sonuç: Çalışmamız sonucunda postmenopozal kadınlarda ürik asit ile lumbar KMY arasında net bir ilişkiden bahsetmek zor gözükmektedir. Ürik asit bilmecesinin çözülmesi ve kemik metabolizması üzerine etkisinin açıklanması için ileri çalışmalara ihtiyaç olduğu kanaatindeyiz. Ayrıca postmenopozal osteopenili hastalardaki ürik asit düzeyi ayrıntılı olarak incelenmelidir.Öğe Postmenopozal osteoporozlu kadınlarda oksidatif stres belirteçlerinin incelenmesi(Galenos Yayınevi, 2018) Dikker, Okan; Şahin, Mustafa; Atar, Sevgi; Bekpınar, SeldağAmaç: Postmenopozal osteoporoz, kemik mineral yoğunluğunun azalmasına bağlı olarak kemiklerde kırılma eğiliminin arttığı bir hastalıktır. Oksidatif stres osteoporoz için önemli bir risk faktörüdür. Çalışmamızda; postmenopozal osteoporozlu kadınlarda, oksidatif stres belirteçlerinin düzeylerinin incelenmesi amaçlanmıştır. Gereç ve Yöntem: Osteoporozu olan ve olmayan postmenopozal kadınlarda ve ayrıca sağlıklı kontrollerde; kemik mineral yoğunluğu, rutin laboratuvar testleri, 25-hidroksivitamin D3, malondialdehit, protein karbonil ve total antioksidan kapasite düzeyleri ölçüldü. Malondialdehit düzeyleri ELISA metoduyla, protein karbonil ve total antioksidan kapasite düzeyleri ise kolorimetrik metodlar ile ölçüldü. Bulgular: Malondialdehit düzeylerinin her iki postmenopozlu grupta azaldığı, protein karbonil düzeylerinin ise osteoporozu olmayan postmenopozlu grupta arttığı saptandı. Sonuç: Bu sonuçlar, osteoporoz ile oksidatif stres arasında bir ilişki kurmayı güçleştirmektedir. Daha spesifik antioksidan ve oksidan moleküllerin ölçümünün konuya katkı sağlayacağını düşünüyoruzÖğe Preoperative evaluation of EDTA-dependent pseudothrombocytopenia before lumbar disc herniation surgery: A case report(2018) Şahin, Mustafa; Savcı, Ünsal; Sahin, Havva Hande KeserEthylenediaminetetraacetic acid-dependent pseudothrombocytopenia (EDTA-PTCP) is an in vitro phenomenon characterized the clustering of platelets following the use of EDTA as an anticoagulant, leading to a decreased analyzer platelet count in a complete blood count (CBC). This report is a description of the case of a 47-year-old male patient admitted to a neurosurgery clinic with the complaints of back and leg pain. A neurological examination and lumbar magnetic resonance imaging revealing extruded disc herniations led to a decision to perform surgery. Thrombocytopenia was detected in the preoperative testing of the patient. The CBC was reanalyzed using citrate. Peripheral blood smears of the patient collected using citrate and EDTA were compared. Thrombocytopenia was not detected in a CBC of the citrated sample and the peripheral smear did not reveal platelet clusters. Pseudothrombocytopenia was considered, as the anamnesis, physical examination findings, and coagulation tests of the patient were not consistent with thrombocytopenia. In conclusion, EDTA-PTCP was diagnosed during the preoperative evaluation of the patient.Öğe Serum asymmetric dimethylarginine levels in patients with vasovagal syncope(NLM (Medline), 2019) Atıcı, Adem; Açıksarı, Gönül; Baycan, Ömer Faruk; Barman, Hasan Ali; Sonsöz, Mehmet Rasih; Şahin, Mustafa; Asoğlu, Ramazan; Demirkıran, AhmetBackground and Objectives: Vasovagal syncope (VVS) is the most common cause of syncope and has multiple pathophysiological mechanisms. Asymmetric dimethylarginine (ADMA) is the major inhibitor of nitric oxide (NO). In this study, we aimed to investigate the relationship between plasma ADMA levels and syncope during the head-up tilt (HUT) test. Materials and Methods: Overall, 97 patients were included in this study. They were above 18 years of age and were admitted to our clinic with the complaint of at least one episode of syncope consistent with VVS. The HUT test was performed in all patients. Patients were divided into the following two groups based on the HUT test results: group 1 included 57 patients with a positive HUT test and group 2 included 35 patients with a negative HUT test. Blood samples were taken before and immediately after the HUT test to measure ADMA levels. Results: No significant intergroup differences were observed concerning gender and age (female gender 68% vs 60%; mean age 24.85 ± 4.01 vs 25.62 ± 3.54 years, respectively, for groups 1 and 2). ADMA values were similar between groups 1 and 2 before the HUT test [ADMA of 958 (544–1418) vs 951 (519–1269); p = 0.794]. In the negative HUT group, no significant differences were observed in ADMA levels before and after the HUT test [ADMA of 951 (519–1269) vs 951 (519–1566); p = 0.764]. However, in the positive HUT group, ADMA levels were significantly decreased following the HUT test [pretest ADMA of 958 (544–1418) vs post-test ADMA of 115 (67–198); p < 0.001]. Conclusion: ADMA levels significantly decreased after the HUT test in patients with VVSÖğe Serum hepcidin levels in active and inactive Behcet’s disease(2019) Dikker, Okan; Yıldırmak, Sembol; Şahin, Mustafa; Usta, Murat; Vardar, Müberra; Vurgun, Eren; Baran, FehmiAim: This study aims to evaluate the alteration of hepcidin synthesis in response to inflammation and to reveal the relationship between hepcidin and acute phase reactants in Behcet’s disease (BD) which is also an inflammatory disease. Material and Methods: That was included 52 BD patients (15 with active, 37 with inactive disease), 13 isolated iron deficiency anemia patients and 13 healthy controls; totally 78 individuals to the study. Patients with chronic disease anemia had 3 active and 1 inactive Behcet's disease. Levels of bioactive hepcidin-25 were measured by ELISA method. Result: Low hepcidin levels were found significantly in inactive BD and the main BD groups comparing to healthy controls (p=0.015, p=0.014, respectively); in BD with anemia of chronic disease group comparing to healthy controls and isolated iron deficiency anemia group (p=0.007, p=0.003, respectively). Besides it was not found any significant difference between hepcidin levels of active BD group and healthy controls (p>0.05). Conclusion: Contrary to its increment pattern in inflammation, increased hepcidin levels in Behcet’s patients were not detected. Alternation of serum Interleukin-6 (IL-6) levels with anti-inflammatory treatments affecting hepcidin levels necessitate hepcidin measurement only in Behcet’s patients who have been recently diagnosed and/or haven't received a treatment before and evaluation of the measurement together with IL-6 levels.Öğe Serum İmmünfiksasyon Elektroforezi Verilerinin Değerlendirilmesi: Bir yıllık deneyim(2018) Dikker, Okan; Şahin, MustafaA Amaç: İmmünfiksasyon elektroforezi (İFE), monoklonal gamopatilerin tanı, tedavi ve takibinde kullanılan altın standart biyokimyasal bir tekniktir. Paraproteinemilerde; paraprotein veya monoklonal protein (M-protein) olarak bilinen immunoglobulinin (Ig) aşırı üretimi olur. M-protein serum veya idrar elektroforezinde sınırları keskin bir band olarak görülebilir. Monoklonal gammopatilerde üretilen paraprotein tipleri IFE yöntemi ile tanımlanabilir. Bu çalışmada, laboratuvarda İFE yöntemi ile saptanan paraproteinemi tiplerini retrospektif olarak değerlendirmeyi ve literatür ile bulguları karşılaştırmayı amaçladık. Gereç ve Yöntem: Bu çalışmada, laboratuvarda yapılan toplam 403 serum İFE analiz raporu retrospektif olarak değerlendirildi. Laboratuvar bilgi sistemi tarandı ve hasta verileri elde edildi. Hastaların serum ve idrar örnekleri Interlab G26 analiz cihazı (Interlab Srl, Roma, İtalya) kullanılarak yapıldı. Bulgular: Çalışmada 96 hastanın serumunda paraprotein bandı tespit edildi (%23). 32 hastada IgG kappa (%33), 19 hastada IgG lambda (%20) tespit edildi. İdrar İFE yapılan hastalarda paraprotein bandı varlığı ise %23 olarak saptandı. Sonuç: Çalışmamızda literatüre benzer şekilde en fazla IgG kappa ve ikinci olarak IgG lambda paraproteinemi tiplerini bulduk. Çalışmamız laboratuvardaki monoklonal gamopati sıklığı hakkında önemli bir projeksiyon sundu ve paraprotein tipinin tahmin edilebilirliğine katkıda bulunmayı hedefledi. Serum ve idrar IFE analizini birlikte yapmak, serum protein elektroforezinde (SPE) paraprotein bandı saptanan veya klinik olarak paraproteinemi düşünülen hastaların tanısına katkı sunacaktır.Öğe Should the Therapeutic Apheresis Method Be Added to Treatment in the COVID-19 Outbreak?(Karger, 2021) Şahin, Mustafa; Yıldız, AbdulkerimDear Editor, The coronavirus outbreak, which started in Wuhan, a city in China, in December 2019, soon spread across the world and was declared a pandemic by the World Health Organization. The disease was identified as novel coronavirus-induced (SARS-CoV-2) COVID-19. No effective antiviral agent or vaccine has been produced for the disease, and deficiencies of medical protective equipment and respiratory support devices are causing difficulties in the fight against COVID-19.Öğe The apoptotic effects of bisphenol A exposure on the rat ovary: an experimental study(Springer Verlag, 2019) Bilgi, Ahmet; Abalı, Remzi; Tonbaklar Bilgi, Pınar; Şahin, Mustafa; Tunçdemir, Matem; Boran, Ahmet BirtanBisphenol A (BPA) is a key endocrine-disrupting chemical (EDC) in the manufacturing industry. It is found in the structure of compounds such as polycarbonate and epoxy in combination with other chemicals. Our objective was to investigate the effect of BPA on rat ovaries. A total of 32 female rats were divided into four equal groups: In group 1 (control), vehicle was administered; in group 2, BPA 50 ?g/day was administered intraperitoneally; in group 3, BPA 100 mg/kg/day was administered intraperitoneally; and in group 4, BPA 100 mg/kg/day and vitamin C (50 mg/kg) were administered intraperitoneally, while vitamin E (50 mg/kg) was administered intramuscularly. Thirty days after the treatment, the effects of BPA on the ovaries were evaluated by terminal deoxynucleotidyltransferase [TdT]-mediated dUTP-biotin nick end labeling (TUNEL) assay. There was no difference in the number of apoptotic cells between group 2 and group 4. In addition, there was no significant difference between control group and group 2, 4. However, the number of apoptotic cells per unit area was significantly increased in group 3 compared with all groups (p < 0.01, p < 0.05). In conclusion, this study showed that high doses of BPA (100 mg/kg/day) have a toxic effect on the ovaries. The fact that the number of apoptotic cells in the group administered with high dose of BPA + 50 mg/kg/day vitamin C + 50 mg/kg/day vitamin E was lower than that of the high-dose BPA-administered group shows that these vitamins may have a protective effect. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.Öğe The role of probiotics in COVID-19 treatment: Gut microbiota can help physicians in the outbreak(2020) Şahin, Mustafa[Abstract Not Available]Öğe Thiol/disulfide homeostasis in patients with telogen effluvium: is oxidative stress important in the pathogenesis of telogen effluvium?(Wolters Kluwer ? Medknow, 2019) Savcı, Ünsal; Şahin, Mustafa; Şenel, Engin; Öztekin, Aynure; Muslu, Ümran; Sungur, Mustafa; Neşelioğlu, Salim; Erel, ÖzcanObjective: The aim of this study was to assess the correlation between telogen effluvium (TE) with the new oxidative stress (OS) indicator of thiol/disulfide balance and to research the role of OS in the pathogenesis of TE. Methods: Our study included 101 patients with TE diagnosis and 39 healthy individuals. Serum thiol/disulfide was measured with a new automated spectrometric method developed by Erel and Neselioglu, and results were compared statistically. Results: Among the six thiol/disulfide parameters, there were statistically significant differences for native thiol, total thiol, disulfide, disulfide/native thiol, disulfide/total thiol, and native thiol/total thiol studied in the patient and control groups (P = 0.042, 0.044, < 0.001, respectively). Conclusions: Based on the results of this study, it can be said that OS is closely associated with TE pathogenesis. There is a need for new studies that will show the possible effects of OS on TE pathogenesis and research different OS markers in addition to thiol/disulfide parameters.
