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Significant progress has been made in understanding the nature of molecular interactions on the cell membrane. To decipher such interactions, molecular scaffolds can be engineered as a tool to modulate these events as they occur on the cell membrane. To guarantee reliability, scaffolds that function as modulators of cell membrane events must be coupled to a targeting moiety with superior chemical versatility. In this regard, nucleic acid aptamers are a suitable class of targeting moieties. Aptamers are inherently chemical in nature, allowing extensive site-specific chemical modification to engineer sensing molecules. Aptamers can be easily selected using a simple laboratory-based in vitro evolution method enabling the design and development of aptamer-based functional molecular scaffolds against wide range of cell surface molecules. This article reviews the application of aptamers as monitors and modulators of molecular interactions on the mammalian cell surface with the aim of increasing our understanding of cell-surface receptor response to external stimuli. The information gained from these types of studies could eventually prove useful in engineering improved medical diagnostics and therapeutics.

Objective: Every year, many people undergo cardiovasculary surgery in the world. Due to improvements in coronary artery bypass surgery (CABG) tecniques, patients in high risk also in advanced age groups, CABG cause many neurological complications like stroke, postoperative delirium, depression, cognitive decline etc. Because of these problems, the effect of CABG on the brain functions gain more importance with respect to effects on postoperative heart status last years. Material and method: In our study, 24 cases undergoing CABG and valve replacement were invastigated. Neuron-specific enolase released from neurons, protein S-100B released from glial cells and nitric oxide that known to have many functions in ischemia were studied in these cases to show cerebral effects of these operations. Also neuropsychological test using for assesment of cognitive functions were performed. We analysed protein S-100B, NSE, NO concentrations in serial venous blood samples taken preoperatively and 1, 6, 24 h and 3, 7 days postoperatively in 24 patients undergoing VR or CABG surgery. Neuropsychological tests were performed preoperatively, and 3. and 7 days after surgery. Results: After performing of neuropsychological tests, cognitive decline was seen in 8 cases. Protein S-100B levels at postoperative 1. and 6. hours and also the mean levels of age and perfusion times were significantly higher in these cases. NSE levels were significantly higher in VR group at postoperative7. days with respect to preoperative levels also. However there was no significant differance between preoperative and postoperative NO levels. Conclusions: Cognitive decline is seen in CABG patients with advanced age and with long perfusion time frequently. Increased protein S-100B levels in these patients are correlated with cerebral influence which cause distrubtion in cognitive functions., Amaç: Her yıl dünyada birçok insan kardiyovasküler cerrahi geçirmektedir. Koroner arterby-pass grafting ameliyatında cerrahi tekniklerdeki ilerleme sonucunda yüksek risk grubundaki hastalar da (hipertansiyon ve diyabet gibi) ameliyata alınabilmektedir. Yüksek riskgrubundaki ve ileri yaştaki hastalara CABG uygulanması beraberinde nörolojikkomplikasyonları da getirmiştir. Ortaya çıkan nörolojik sorunlar inme, ameliyat sonrasıdeliryum, bilişsel bozukluklar ve depresyondur. Bu nedenle ilgi son yıllarda kalbin ameliyatsonrası durumu yerine CABG’nin beyin üzerine de olan etkilerine kaymıştır.Gereç ve yöntem: Çalışmamıza CABG ve valf replasmanı geçiren 24 olgu alındı. Buolgularda serebral hasarı göstermek amacı ile gliadan salınan S-100B protein, nöronlardansalınan nöron spesifik enolaz ve iskemi patofizyolojisinde birçok fonksiyonu olan nitrik oksiddüzeyleri ölçüldü. Ayrıca hastaların bilişsel fonksiyonlarını ölçen nöropsikolojik testleruygulandı. Bu amaçla CABG ve VR ameliyatı geçiren 24 olgudan ameliyat öncesi veameliyattan sonra 1., 6. ve 24. saatler ve 3. ve 7. günlerde venöz kan alınarak S-100Bprotein, NSE ve NO düzeyleri ölçüldü. Nöropsikolojik testler ameliyattan önce ve ameliyatsonrası 3. ve 7. günlerde uygulandı.Bulgular: Nöropsikolojik testler sonucunda 8 olguda bilişsel fonksiyon kaybı saptandı. Buolgularda ameliyat sonrası 1. ve 6. saatteki S-100B protein düzeyleri, perfüzyon zamanı veolguların yaş ortalaması bilişsel kayıp saptanmayan grupla karşılaştırıldığında anlamlıyüksek bulundu. NSE, VR grubunda ameliyattan sonra 7.gün ameliyat öncesi değerleregöre anlamlı yüksek bulundu ancak bunun bilişsel fonksiyon kaybıyla bir bağlantısı saptanmadı. Ameliyat öncesi ve ameliyat sonrası NO düzeylerinde ise anlamlı fark bulunmadı.Sonuç: CABG hastaları içinde yaş ortalaması yüksek ve perfüzyon zamanı uzun olanlardabilişsel fonksiyon kaybı daha fazla görülmektedir. Artan serum S-100B protein düzeyleriserebral etkilenme ve buna bağlı bilişsel fonksiyon kaybı ile koreledir

Amaç: Çeşitli kardiyovasküler hastalıkların oluşumunda mevsimlerin belirgin etkisiolduğu görülmüştür. Derin ven trombozu için mevsimsel ilişki konusunda yapılançalışmaların sonuçları tartışmalıdır. Yaptığımız çalışmanın amacı derin ven trombozugelişiminde mevsimsel farklılıkların yanı sıra komorbid risk faktörlerinin muhtemeletkisinin araştırılmasıdır.Gereç ve yöntem: Ocak 1997- Temmuz 2008 arasında başvuran 398 derin ventrombozu tanısı konulup, izlenen hastanın mevsimsel farklılık açısından alt gruplaraayrılarak retrospektif olarak incelemesi yapılmıştır.Bulgular: Mevsimsel analiz sonucu derin ven trombozu görülme sıklığı ilkbaharda %31, yaz aylarında %19, sonbaharda %24 ve kış %26 olarak tespit edildi (p=0,024).Aylara göre yapılan incelemede, en düşük görülme oranı % 4,8 ile Temmuz ayındaolurken, en yüksek görülme oranı %11,3 ile Mayıs ve Mart aylarındaydı. Kronobiyolojikanaliz sonuçları mevsimsel değişimin istatistiksel anlamı olduğunu gösterdi (p=0,043).Sonuç: Yaptığımız çalışma hastanemizde derin ven trombozu ile yatırılan olgularınözellikle yaz aylarında daha azaldığını, ilk bahar aylarında ise arttığını saptadık.Sıcaklık açısından soğuk havanın hüküm sürdüğü ayların ve buna bağlıhiperkoagülbilitenin yüksek risk yaratan bir durum olabileceği düşünülmektedir

In this paper we address the problem of predicting a time series using the ARMA (autoregressive moving average) model, under minimal assumptions on the noise terms. Using regret minimization techniques, we develop effective online learning algorithms for the prediction problem, without assuming that the noise terms are Gaussian, identically distributed or even independent. Furthermore, we show that our algorithm's performances asymptotically approaches the performance of the best ARMA model in hindsight., Comment: 17 pages, 6 figures

A variety of vascular closure devices (VCD) are widely used worlwide with very low access-site related complication rates and favorable patient related consequences even in endovascular procedures in which large-bore sheaths are required. The suture-mediated Prostar XL® VCD is stated to be eligible for up to 26Fr sheaths' puncture sites. The main criticized point of Prostar XL® is the complexity of the deployment steps with resultant experience of the interventionist, which is pointed to be the major cause of adverse events. The aim of this report is to warn the interventionists to take into account of this rare complication. Copyright © 2012 by Türkiye Klinikleri.

Aim. The aim of this study was to measure the changes in the levels of soluble adhesion molecules involved in acute inflammation during ischemia-reperfusion in adults who underwent open-heart surgery using blood and blood-insulin cardioplegia and to examine the differences in tissue damage at the molecular level as a consequence of insulin's effect on myocardial energy metabolism.

Aim Heparin-coated circuits have dramatic effects on the coagulation cascade, but their role on complement activation has not been clearly defined. in this clinical study the effect of heparin-coated circuits on static lung compliance and pulmonary vascular resistance is described.

Background. Thrombolytic therapy is still not used widely for treatment of deep vein thrombosis despite its known efficacy. This reluctance to use it stems from worries about its hemorrhagic complications.

A hydatid cyst of the heart is rare. Surgical treatment is the preferable method in the treatment of cardiac echinococcosis. A 27-year-old patient with right ventricular hydatid cyst causing recurrent pulmonary emboli and diagnosed by 2-dimensional echocardiography and treated surgically is presented.

Chylous ascites due to constrictive pericarditis is an extremely rare clinical entity, possibly caused by the augmented lymph production and high impedance to lymph drainage due to central venous hypertension. The authors describe a patient with chylous ascites caused by constrictive pericarditis in the absence of lymphatic obstruction. Cardiac catheterization is essential for the confirmation of accurate diagnosis of constrictive pericarditis. Magnetic resonance imaging of the heart is also very helpful in the diagnosis. The patient was symptom free and his ascites and edema completely resolved after pericardiectomy.

In April and May 1996, two cases of PDA ligation were performed firstly in Turkey by the method of video assisted thoracoscopic surgery (VATS) in Dokuz Eylul Medical Faculty, Thoracic and Cardiovascular Surgery Department. There was not any complication in these patients in the postoperative period and they were discharged on the second day in symptom-free condition by the detection of closed ductus in their echocardiographic examination. Between February 1993 and October 1996, a total of 46 patients have undergone interventional application by VATS. While in six of these patients the procedure could not be manipulated because of massive pleural fibrosis, there was no mortality or morbidity among the patients, and they were discharged on average on the second day, The ratio of complications, such as bleeding, air leak, arrhythmia and empyema are so low in these operations, and hospital stay, with return to work time are shorter than with the open technique.

Coronary artery bypass grafting (CABG) is one of the major treatment methods of coronary artery disease. CABG is an open-heart surgery that uses cardiopulmonary bypass (CPB). After CPB, it is well known that neurological and neuropsychological complications may occur. The purpose of this study was to evaluate brain perfusion patterns before and after CPB and to locate brain perfusion changes in patients with neurological and neuropsycological complications after CPB. Methods: Twenty-five patients who underwent open-heart surgery (22 CABG, 3 valve replacement) and 5 patients (4 cholecystectomy, 1 periferic vascular surgery) as a control group were included in the study. The Tc-99m-HMPAO injected dose was 925 MBq. Brain perfusion SPECT images were obtained 30-60 min postinjection using a dedicated triple-head brain SPECT camera, Imaging was performed 1 wk before and 4-6 wk after surgery. Technetium-99m-HMPAO brain SPECT slices were evaluated visually and semiquantitatively. Results: None of the patients had severe neurologic complications. Neuropsychological deficits occurred in eight patients after CABG. Cognitive deterioration and depressive mood occurred in five patients. Disorientation, agitation and confusion periods were present in another two patients. Frontal hypoperfusion was found in these patients by visual and semiquantitative evaluations (p = 0.0277) and left parietal hypoperfusion was also present semiquantitatively (p = 0.0277). Visual hallucinations occurred in one patient. Computed tomography of these patients was normal. No perfusion abnormalities were observed in the patient with visual hallucinations and in patients without symptoms after open-heart surgery nor in the control group. Brain SPECT was repeated in two symptomatic patients 5 mo after CABG. Frontal hypoperfusion became normal, and these patients' symptoms disappeared. Conclusion: The results of this study indicate that regional cortical hypoperfusion may occur in patients with neuropsychological complications after CABG. Technetium-99m-HMPAO brain SPECT is a useful method to locate and determine brain perfusion changes after CABG.

Wide resection of tumors involving the glenoid region of the scapula compromises a center of motion in the shoulder joint and can cause significant loss of function. Two patients with aggressive tumor of the scapula were treated with wide resection and reconstruction using an osteoarticular acetabular allograft. The ball and socket geometry of the newly reconstructed joint and secure reattachment of soft tissues in the allograft provided a stable shoulder joint. The functional results of the two patients were 87% and 93%, respectively according to the Musculoskeletal Tumor Society system. In a select group of patients with locally aggressive lesions of the scapula, a surgical reconstruction with an osteoarticular allograft would yield satisfactory functional and cosmetic results

We evaluated totally 67 patients having primary lung cancer underwent surgical procedures between January 1990 - March 1997 in our institution. The curative resection procedures were indicated in the stages up to the IIIb. The operative choices were lobectomy (35 %), bilobectomy (4 %), pneumonectomy (35 %), excisional biopsy + wed %), debulking (4 %) and metastathectomy (9 %). Mediastinal lymph node dissection was routinely performed in the resection procedures. Total mortality rate was 25 % with the hospital mortality of 2 patients (3 %). Significant differentiation was noticed in the staging ratios between the pre and postoperative evaluation. In order to choose the most appropriate therapeutic plan and determining the prognosis, the exact stage must be detected by the aid of mediastinal lymph node dissection.