Tıp Fakültesi, Tıbbi Biyoloji ve Genetik Anabilim Dalı Koleksiyonu
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Öğe Corrigendum to “The importance of boron in biological systems” [J. Trace Elem. Med. Biol. 45 (2018) 156–162](Elsevier GmbH, 2018) Koç, A.Öğe Brain abscess and bronchopneumonia caused by acinetobacter baumannii in a 2-year-old femalesheep(Taylor & francıs ltd, 2-4 park square, mılton park, abıngdon or14 4rn, oxon, england, 2018) Eroksuz, Yesari; Otlu, Baris; Eroksuz, Hatice; Gursoy, Nafia Canan; Yerlikaya, Zeynep; Incili, Canan Akdeniz; Karabulut, Burak; Timurkaan, Necati; Timurkan, Mehmet OzkanÖğe A rare mutation in the epg5 gene causes vici syndrome(Lıppıncott wıllıams & wılkıns, two commerce sq, 2001 market st, phıladelphıa, pa 19103 usa, 2018) Demiral, Emine; Sen, Askin; Esener, Zeynep; Ceylaner, Serdar; Tekedereli, IbrahimÖğe Single or multiple perforations with varying locations as a complication of intestinal Behçet s disease report of three cases(Scandinavian Journal of Gastroenterology, 2005; 40: 599 / 603., 2005) Işık, Burak; Ara, Cengiz; Kırımlıoğlu, Vedat; Söğütlü, Gökhan; Yılmaz, Sezai; Kırımlıoğlu, HaleIntestinal ulcers in Behc¸et’s disease (BD) tend to cause perforation with significant morbidity. The optimal surgical procedure in such cases is controversial and the postoperative period can be eventful with an unpredictable course. We report three cases of perforations with varying locations in three patients with long-standing Behc¸et’s disease. Two patients required two and one patient required four operations. It is emphasized that the clinician must be alert in a patient with BD when abdominal symptoms accompany the clinical picture. As soon as the diagnosis is reached, surgical intervention with limited resection must be performed. Endoscopic examination and careful medication play major roles in the follow-up.Öğe Abdominal compartment syndrome due to distended rectal stump(Turk J Gastroenterol 2007; 18 (3): 192-194, 2007) Yılmaz, Sezai; Işık, Burak; Uğraş, Murat Yahya; Söğütlü, Gökhan; Ara, Cengiz; Yılmaz, SezaiAbdominal compartment syndrome is a serious and life-threatening condition that requires early recognition and urgent decompressive laparotomy. This case report describes an abdominal compartment syndrome due to a distended rectal stump. The patient had a previous sigmoid resection with colostomy performed for sigmoid volvulus. As far as we know, this is the first report of abdominal compartment syndrome due to rectal stump. In such cases, high index of suspicion and early intervention affect the clinical course.Öğe Leishmania major Promastigot hücrelerine karşı makrofajlardan nitrojen radikali ve tümör nekroz faktörü salgılanması(İnfeksiyon Dergisi, 1996) Aybay, Cemalettin; İmir, Turgut; Kayhan, Çağlar; Kayhan, BaşakÖğe İnsan serumunun leishmania major promastigot hücreleri üzerine öldürücü etkisi(Türkiye Parazitoloji Dergisi, 1997) Aybay, Cemalettin; Çağlar, Kayhan; İmir, Turgut; Kayhan, BaşakÖğe The comparison of the effect of somatostatin and SMS 201 995 on enzyme change following endoscopic retrograde cholangiopancreotography(Gazi MEdical Journal, 1998) Görgül, Ahmet; Kayhan, Burçak; Menteş, Bülent; Kayhan, Başak; Akı, ZeynepÖğe Fare makrofajlarından nitrik oksit sentezine interferon gamma ve lipopolisakkaritin etkileri(Türkiye Tıp Dergisi, 1999) Tayşi, Bülent; Kayhan, Başak; Aybay, Cemalettin; İmir, TurgutNitrik oksit (NO) makrofajların sitotoksik etkisinin ortaya çıkmasında rol almaktadır. NO’in yapımını nitrik oksit sentaz (NOS) enzimi katalize etmektedir. Sitozolde bulunan bu enzimin, enzimi kodlayan genler, hücre veya organ lokalizasyonlarındaki farklılıklar ve kalsiyum uyarımına verdikleri yanıta göre iki izoformu tanımlanmıştır: 1. Uyarılabilir NOS (inducible NOS-iNOS), 2. Yapısal NOS (constitutional NOS-cNOS). Makrofajlarda iNOS bulunur. Lipopolisakkarit (LPS) ve interferon gamma (IFN-g) iNOS enzimini uyaran maddeler arasındadır. Patojen ajanların IFN-g ile birlikte makrofajların NO salgılanması üzerine sinerjistik etki yapmalarının yüksek düzeylerde üretildiğinde konakçı hücre ve dokularına karşı da zararlı etkileri olabilen NO’in ortamda patojen bir ajan bulunmadıkça üretilmemesi şeklinde bir çeşit düzenleyici mekanizma oluşturduğu düşünülmektedir. Ancak, fare kökenli makrofaj tiplerinin IFN-g ve LPS’in tek başına veya beraber uygulanması durumundaki NO yanıtları, kullanılan hücre tipleri ve araştırma grupları arasında farklılıklar göstermektedir. Bu çalışmada fare makrofaj kökenli RAW 264.7 hücresi kullanılarak IFN-g, LPS ve IFN-g+LPS kombinasyonunun NO sentezi üzerindeki etkileri ve bu etkilerin NG-nitro-L-arjinin-metil ester (L-NAME) ve polimiksin B ile inhibisyonu araştırıldı. Kültür süpernatanlarında NO düzeyi Griess ayıracı ile nitrit düzeyi ölçülerek belirlendi. Sadece IFN-g ile uyarılan hücrelerde doza bağımlı ve LPS uyarımı ile kıyaslanabilir düzeyde NO yanıtının oluştuğu saptandı. IFN-g+LPS kombinasyonu ile uyarılan hücrelerden, tek başına IFN-gveya LPS ile uyarılanlara göre daha fazla NO salgılanmaktadır. IFN-g veya LPS aracılığı ile NO salgılanması L-NAME ile baskılanmaktadır. LPS’nin biyolojik etkilerini inhibe etmek amacıyla in vitro ortamlarda sıkça kullanılan polimiksin B, LPS ile uyarılan hücrelerdeki NO yanıtını inhibe etmenin yanısıra, IFN-g ile uyarılan hücrelerde NO yanıtını da anlamlı düzeyde (p=0.024) baskılamaktadır.Öğe A competitive enzyme linked immunosorbent assay ELISA for determination of human albumin in the nanogram range(Gazi Medical Journal, 1999) Aybay, Cemalettin; İmir, Turgut; Kayhan, BaşakÖğe The combined use of dimethyl sulfoxide with chemotherapeutics on bladder cell culture(Gazi Medical Journal, 2001) Sözen, Sinan; Yaman, Önder; Oğuzülgen, İbrahim; Kayhan, Başak; Tuncel, Aytuğ; Alkibay, Turgut; Bozkırlı, İbrahimÖğe Effect of mucosal immunomodulation with fed cholera toxin on healing of experimental colonic anastomosis(Diseases of the Colon & Rectum, 2002) Kaplan, Mehmet; Menteş, Bülent; Tatlıcıoğlu, Ertan; Kayhan, Başak; Aybay, CemalettinThe aim of this study was to investigate in rats whether preoperative orogastric administration of low doses of cholera toxin would influence the mechanical strength of experimental colonic anastomosis on the basis of the gut mucosal immunomodulation effect of this antigen. METHODS: The cholera toxin group (n 14) was fed 10 g of cholera toxin in phosphate-buffered saline three times before surgery at 10-day intervals, whereas the controls (n 14) received phosphate-buffered saline only. Twenty-four hours after the last dose of cholera toxin (or placebo in control group), the animals underwent left colonic transection and anastomosis. Seven days after colonic transection-anastomosis, the bursting pressure of the anastomotic segment was recorded in situ. Perianastomotic and extra-anastomotic tissue samples were obtained for measurements of tissue transforming growth factor-beta, interleukin-6, and interferon-gamma levels with enzyme-linked immunosorbent assay. RESULTS: Cholera toxin administration resulted in a significantly higher bursting pressure than in the control group (165.78 12.37 vs. 138.4 7.87 mmHg; P 0.001). Compared with the control group, the heightened mechanical strength of colonic anastomosis provided by cholera toxin was associated with significant increases in the perianastomotic tissue levels of transforming growth factor-beta (199.34 24.85 vs. 70.66 10.63 pg/ml; P 0.001) and interleukin-6 (439.31 95.14 vs. 289.57 96.59 pg/ml; P 0.001), whereas interferongamma was significantly lower (174.04 44.82 vs. 219.00 31.35 pg/ml; P 0.05). This cytokine pattern induced by cholera toxin in the wound milieu was also found to be similar in the extra-anastomotic colon. CONCLUSION: The mechanical strength of uncomplicated experimental colonic anastomosis increased significantly with gut mucosal immunomodulation with repeated low preoperative doses of cholera toxin. This enhanced healing had significant positive correlation with the colonic tissue level of transforming growth factor-beta and inverse correlation with interferon-gamma. If the relevant dose regimen is identified and its safety is assured in humans, gut mucosal immunomodulation might provide an efficient, safe, and inexpensive tool to improve surgical outcome in colorectal surgery, particularly in high-risk situations.Öğe Raw 264.7 makrofaj hücrelerinden lipopolisakkarid aracılığı ile nitrik oksid salgılanmasına monofosforil lipid A nın etkisi(Flora, 2003) Aybay, Cemalettin; İmir, Turgut; Gülsayın, Cengiz; Kayhan, BaşakLipopolisakkaridin (LPS veya endotoksin) toksik etkilerinden lipid A kısmı sorumludur. Lipid A’nın yapısal analogları ve öncül moleküllerinin tanımlanmasından sonra bunların LPS’nin biyolojik etkilerine karflı kompetetif antagonizma gösterdikleri anlaflılmıfltır. Bu çalıflmada Salmonella minnesota LPS’si ile uyarılan RAW 264.7 makrofaj hücrelerinden nitrik oksid (NO) salgılanmasına Salmonella minnesota kaynaklı monofosforil lipid A’nın etkisi arafltırıldı. Monofosforil lipid A’nın kendisi makrofajlardan doza bağımlı bir flekilde NO salgılanmasına neden olmakla birlikte, belirli konsantrasyonlardaki monofosforil lipid A, LPS aracılığı ile makrofajlardan NO salgılanmasını engellemektedir. Monofosforil lipid A’nın 0.125 µg/mL ve daha az konsantrasyonlarında, NO salgılatma kapasitesinin azaldığı ve LPS aracılığı ile RAW 264.7 makrofajlarından NO salgılanmasını baskıladığı saptandı.Öğe Glatiramer acetate Copaxone regulates nitric oxide and related cytokine secretion in experimental autoimmune encephalomyelitis(Immunology Letters, 2003) Kayhan, Başak; Aharoni, Rina; Arnon, RuthNitric oxide (NO) is an important mediator involved in the pathogenesis of experimental autoimmune encephalomyelitis (EAE) and multiple sclerosis (MS). We examined the effect of glatiramer acetate (GA), an agent with suppressing effect on EAE and of therapeutic value for the treatment of MS, on the secretion of NO, as well as of the NO regulating cytokines. We observed that induction of EAE leads to 4-fold elevation in NO secretion and that treatment of the EAE mice by GA indeed leads to a significant reduction in the NO secretion by the splenocytes in response to the encephalitogen. A parallel decrease was observed in the secretion of the NO inducing cytokine IL-1b. On the other hand, the secretion level of NO modulating cytokines IL-10 and IL-13 was significantly augmented. The correlation between these findings and the therapeutic effect of GA is discussed.Öğe Secretion of brain derived neurotrophic factor BDNF interleukin 10 and transforming growth factor beta by glatiramer acetate specific T cells in the brain(Neurology, 2004) Aharoni, Rina; Kayhan, Başak; Sela, Michael; Arnon, RuthÖğe Can IL 2R alpha be a valuable marker along with CA 19 9 in the diagnosis of chronic pancreatitis and pancreatic cancer(International journal of biological markers, 2004) Kayhan, Başak; Kayhan, Burçak; Akdoğan, MeralPancreatic cancer is characterized initially by non-specific abdominal symptoms followed by rapid tumor progression. Although chronic pancreatitis is a benign disorder, it can be one of the causative factors of pancreatic cancer. The level of the tumor marker carbohydrate antigen 19-9 (CA 19-9) in pancreatic cancer does not correlate with the stage of the neoplasm. Soluble interleukin 2 receptor (sIL-2R) is a cytokine that shows increased levels during some inflammatory processes and malignant disorders. AIM: Our aim in this study was to investigate whether sIL-2Ralpha levels can be used in association with CA 19-9 in the early diagnosis of pancreatic cancer and chronic pancreatitis. PATIENTS: Serum samples were obtained from the blood of 21 pancreatic cancer patients without distant metastasis who were deemed inoperable, 16 chronic pancreatitis patients and 20 normal volunteers. RESULTS: We did not find any significant differences in CA 19-9 levels between normal controls and patients with chronic pancreatitis. There was a significant difference in the levels between the control group and the pancreatic cancer group (p = 0.003) and between patients with chronic pancreatitis and those with pancreatic cancer (p = 0.004). Although there was no significant difference in sIL-2Ralpha levels between the control group and the patient groups, we found a slight correlation between sIL-2Ralpha and CA 19-9 levels in the pancreatic cancer group (p = 0.003, r = 0.623) and a more marked correlation in the chronic pancreatitis group (p < 0.01, r = 0.751). CONCLUSION: According to our results, sIL-2Ralpha alone is not a good candidate marker in the diagnosis of pancreatic cancer; it can, however, be used in association with CA 19-9 for this purpose.Öğe A DNA aptamer prevents influenza infection by blocking the receptor binding region of the viral hemagglutinin(Journal of Biological Chemistry, 2004) Jeon, Sung Ho; Kayhan, Başak; Benyedidia, Tamar; Arnon, RuthInfluenza A virus infection is a major source of morbidity and mortality worldwide. Current means of control for influenza are based on prophylaxis by vaccines and on treatment by the available specific influenza neuraminidase inhibitor drugs. The approach taken in the present study is to prevent and/or ameliorate influenza infection by site-specific blocking of the viral binding to host cell receptors. We describe a novel oligonucleotide, known also as an aptamer, which has been designed to complement the receptor-binding region of the influenza hemagglutinin molecule. It was constructed by screening a DNA library and processing by the selective evolution of ligands by exponential enrichment (SELEX) procedure. We show that this DNA aptamer is indeed capable of inhibiting the hemagglutinin capacity of the virus, as well as in the prevention of viral infectivity in vitro, in tissue culture. Furthermore, it inhibits viral infection by different influenza strains in an animal model, as manifested by 90 –99% reduction of virus burden in the lungs of treated mice. The mode of action of this aptamer is by blocking the binding of influenza virus to target cell receptors and consequently prevention of the virus invasion into the host cells.Öğe Therapeutic effect of the immunomodulator glatiramer acetate on trinitrobenzene sulfonic acid induced experimental colitis(Inflammatory Bowel Diseases, 2005) Aharoni, Rina; Kayhan, Başak; Arnon, RuthInflammatory bowel diseases are characterized by detrimental immune reactivity in the gut and imbalance between proinflammatory and antiinflammatory reactivity. In an attempt to downregulate inflammatory bowel disease, we tested whether the immunomodulator glatiramer acetate (GA; Copaxone®, copolymer 1), an approved drug for the treatment of multiple sclerosis, can ameliorate trinitrobenzene sulfonic acid (TNBS)-induced colitis, a murine model that resembles human Crohn's disease. Experimental colitis was induced by rectal instillation of TNBS in 3 mice strains: BALB/c, SJL/J, and (SJL/JXBALB/c)F1, and its severity was evaluated by gross colon injury, histologic damage, body weight, and survival rate. We studied the effect of GA on all these parameters as well as on lymphocyte reactivity manifested by proliferation and secretion of tumor necrosis factor-α, and transforming growth factor-β. GA treatment significantly suppressed the various manifestations of TNBS-induced colitis as demonstrated by substantial reduction in the macroscopic colonic damage, preservation of the microscopic colonic structure, reduced weight loss, and improved long-term survival, in GA treated mice compared with untreated mice. The parenteral route was more effective than the oral route. GA suppressed the proliferation of local mesenteric lymphocytes to syngeneic colon extract and the detrimental tumor necrosis factor-α secretion. In addition, it induced a beneficial secretion of transforming growth factor-β. The ability of GA to effectively modulate the clinical manifestations and the detrimental immune response involved in experimental colitis warrants further studies to determine the clinical efficacy of GA in the treatment of human inflammatory bowel diseases.Öğe Infection of dendritic cells by a gamma 2 herpesvirus induces functional modulation(Journal of immunology, 2005) Flano, Emillio; Kayhan, Başak; Woodland, David; Blackman, MarciaThe murine γ-herpesvirus-68 (γHV68) establishes viral latency in dendritic cells (DCs). In the present study, we examined the specific consequences of DC infection by γHV68, both in vivo and in vitro. Ex vivo analysis of infected mice showed that the virus colonizes respiratory DCs very early after infection and that all subsets of splenic DCs analyzed are viral targets. We have developed and characterized an in vitro model of γHV68 infection of DCs. Using this model, we demonstrated that viral infection neither induces full DC maturation nor interferes with exogenous activation, which is assessed by cell surface phenotypic changes. However, whereas γHV68 infection alone failed to elicit cytokine secretion, IL-10 secretion of exogenously activated DCs was enhanced. Furthermore, γHV68-infected DCs efficiently stimulated virus-specific T cell hybridomas but failed to induce alloreactive stimulation of normal T cells. These data indicate that viral infection doesn’t interfere with Ag processing and presentation but does interfere with the ability of DCs to activate T cells. The inhibition of T cell activation was partially reversed by blocking IL-10. Analysis of infected mice shows elevated levels of IL-10 expression in DCs and that lack of endogenous IL-10 is associated with decreased γHV68 long-term latency. Taken together, these observations indicate that γ2-herpesvirus infection of DCs is a mechanism of viral immune evasion, partially mediated by IL-10.Öğe Serum pankreatik elastaz 1 acil servislerde akut ankreatit tanısı için güvenilir bir yöntem olabilir mi?(Akademik Gastroenteroloji Dergisi, 2006) Kayhan, Başak; Kayhan, Burçak; Özaslan, Ersan; Özer, DiğdemAcil servise karın ağrısı ile başvuran hastaların bir kısmında, rutin radyolojik ve laboratuvar testleri ile akut pankreatit teşhis edilememektedir. Bu çalışmada, akut pankreatit tanısında serum elastazın duyarlılığı araştırılmıştır. Gereç ve yöntem: Acil servise karın ağrı- sı ile başvuran, tanı almadan önce karın ağrısı kendiliğinden iyileşen, aynı zamanda radyolojik ve laboratuvar bulguları normal olan 80 hastanın serum elastaz düzeyine bakılmıştır. Bulgular: Laboratuvar sonuçları ve USG bulguları normal olan 2 olguda, elastaz düzeyi yüksek bulunmuş- tur. Bu olgular daha sonra pankreatit bulguları göstermiş ve hastaneye yatırılmıştır. Sonuç: Serum pankreatik elastaz, acil serviste akut pankreatit tanısında diğer laboratuvar testlerinden daha özgül ve duyarlı olabilir.
