PubMed İndeksli Yayınlar Koleksiyonu
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Article Citation Count: 0Cultural Context Shapes the Selection and Adaptiveness of Interpersonal Emotion Regulation Strategies(Amer Psychological Assoc, 2024) Pruessner, Luise; Altan-Atalay, AyseIn everyday life, we commonly experience, express, and regulate our emotions in interpersonal contexts. However, much of the existing research on utilizing others for modulating one's emotions has focused on Western, individualistic cultures, leaving a significant gap in understanding how the selection and adaptiveness of interpersonal emotion regulation (IER) strategies vary across cultural contexts. This cross-national comparison study aims to bridge this gap by examining intrinsic IER in 1,187 participants from Turkey and Germany, which are characterized by different cultural norms, values, and socialization practices regarding emotional experience and expression. All participants completed measures of intrinsic IER strategies alongside measures of adaptive outcomes, including depression, anxiety, negative affect, and positive affect. The results revealed cross-national differences between Turkish and German individuals in terms of the intrinsic IER strategies most frequently selected and their associations with depression, anxiety, negative affect, and positive affect. These findings emphasize the significance of cultural context in intrinsic IER and offer insights into the conditions under which these strategies are linked to adaptive outcomes. By recognizing the cultural nuances in how people navigate their emotions via social interactions, clinicians and researchers can develop more culturally sensitive interventions tailored to the specific needs of individuals in diverse cultural contexts.Article Citation Count: 0Maternal Underestimations and Overestimations of Their Infants' Word Comprehension: Effects on Mothers' Verbal Input and Infants' Receptive Vocabulary(Cambridge Univ Press, 2024) Ertas, Sura; Kuntay, Aylin C.; Aktan-Erciyes, AsliInfants' language is often measured indirectly via parent reports, but mothers may underestimate or overestimate their infants' word comprehension. The current study examined estimations of mothers from diverse educational backgrounds regarding their infants' word comprehension and how these estimations are associated with their verbal input and infants' receptive vocabulary at 14 months. We compared 34 infants' looking-while- listening (LWL) performances with the mothers' Turkish Communicative Development Inventory (TCDI) reports to calculate the mothers' overestimation and underestimation. During free-play sessions, we assessed the mothers' number of words, number of clauses, lexical diversity, and linguistic complexity. We found that mothers have overestimations and underestimations regardless of their educational background. Crucially, mothers' only overestimations were positively associated with their number of words and lexical diversity. Mothers' verbal input was not related to infants' receptive vocabulary scores. The findings suggest that mothers' input might be aligned with their estimations of their infants' language capabilities, which might not reflect the infants' true performance.Article Citation Count: 0Regime Switching in Coupled Nonlinear Systems: Sources, Prediction, and Control-Minireview and Perspective on the Focus Issue(Aip Publishing, 2024) Franovic, Igor; Eydam, Sebastian; Eroglu, DenizRegime switching, the process where complex systems undergo transitions between qualitatively different dynamical states due to changes in their conditions, is a widespread phenomenon, from climate and ocean circulation, to ecosystems, power grids, and the brain. Capturing the mechanisms that give rise to isolated or sequential switching dynamics, as well as developing generic and robust methods for forecasting, detecting, and controlling them is essential for maintaining optimal performance and preventing dysfunctions or even collapses in complex systems. This Focus Issue provides new insights into regime switching, covering the recent advances in theoretical analysis harnessing the reduction approaches, as well as data-driven detection methods and non-feedback control strategies. Some of the key challenges addressed include the development of reduction techniques for coupled stochastic and adaptive systems, the influence of multiple timescale dynamics on chaotic structures and cyclic patterns in forced systems, and the role of chaotic saddles and heteroclinic cycles in pattern switching in coupled oscillators. The contributions further highlight deep learning applications for predicting power grid failures, the use of blinking networks to enhance synchronization, creating adaptive strategies to control epidemic spreading, and non-feedback control strategies to suppress epileptic seizures. These developments are intended to catalyze further dialog between the different branches of complexity.Article Citation Count: 0Investigation and Development of Novel Synthetic Approaches for Synthesis of Euxanthone and Derived Dyes(Royal Soc Chemistry, 2024) Cetin, M. MustafaThe historical dye Indian yellow, derived from euxanthic acid formed from 1,7-dihydroxyxanthone (euxanthone) and methyl (tri-O-acetyl-alpha-d-glucopyranosyl bromide) uronate, has significantly influenced the art world due to its vibrant color and unique production process. Studying Indian yellow is important for its historical relevance and impact on various art forms, as well as the challenges in its synthetic production. Herein, this work investigates the synthesis of the two main components, a novel method for obtaining euxanthone, and attempts to produce euxanthic acid and Indian yellow. All key intermediates and desired compounds have successfully been synthesized with good to high isolated yields, and characterized using different analytical and spectroscopic techniques. A proposed mechanism for euxanthone synthesis via 2,6,2 ',5 '-tetramethoxybenzophenone formation is also offered. During this process, 2,7-dihydroxyxanthone has also been synthesized, revealing an equilibration reaction that produced three isomeric tetramethoxybenzophenones, confirmed by both GC/MS and NMR. Following the synthesis of euxanthone and clarification of the equilibration, the production of Indian yellow via euxanthic acid formation has further been explored.Article Citation Count: 0Distinct Deregulation Trends of Transcriptional Protein Complexes in Aging Naive T Cells(Oxford Univ Press, 2024) Kokrek, Emel; Pir, PinarThe impact of aging on T cell subsets, specifically CD4+ and CD8+ T cells, leading to immune system dysfunction has been the focus of scientific investigation due to its potential to reverse age-associated deterioration. Transcriptomic and epigenomic studies have identified the primary regulators in T cell aging. However, comprehending the underlying dynamic mechanisms requires studying these proteins with their interactors. Here, we integrated single-cell RNA sequencing data of naive CD4+ and CD8+ T cells obtained from 3 different age groups with protein-protein and domain-domain interaction networks to predict and compare the transcriptional protein complexes and identify their capacity to explain age-associated variances. Our novel approach revealed significant effects of aging on the repertoire of complexes, which remains unchanged in naive CD4+ T cells, while in naive CD8+ T cells, it diminishes. In both cell types, there was major deregulation of complexes with the same composition, involving a range of transcription factors. This aging-associated deregulation is characterized by a specific set of protein complexes in naive CD4+ T cells, but this pattern is not observed in naive CD8+ T cells. SMAD3 and BCL11A complexes emerge as key markers in defining a trajectory in aging naive CD4+ T cells. These complexes can accurately distinguish between 3 different age groups, indicating their potential as targets. The direct link between SMAD3 and FOS complexes whose regulatory role has been previously implicated in aging and MBD3 as the novel key link between SMAD3 and BCL11A complexes implicates a coordinated mechanism in age-associated deregulation.Article Citation Count: 0Effective Drug Design Screening in Bacterial Glycolytic Enzymes Via Targeting Alternative Allosteric Sites(Elsevier Science inc, 2024) Turkmenoglu, Ipek; Kurtulus, Gamze; Sesal, Cenk; Kurkcuoglu, Ozge; Ayyildiz, Merve; Celiker, Serkan; Akten, Ebru DemetThree glycolytic enzymes phosphofructokinase (PFK), glyceraldehyde-3-phosphate dehydrogenase (GADPH) and pyruvate kinase (PK) that belong to Staphylococcus aureus were used as targets for screening a dataset composed of 7229 compounds of which 1416 were FDA-approved. Instead of catalytic sites, evolutionarily less conserved allosteric sites were targeted to identify compounds that would selectively bind the bacteria's glycolytic enzymes instead of the human host. Seven different allosteric sites provided by three enzymes were used in independent screening experiments via docking. For each of the seven sites, a total of 723 compounds were selected as the top 10 % which displayed the highest binding affinities. All compounds were then united to yield the top 54 drug candidates shared by all seven sites. Next, 17 out of 54 were selected and subjected to in vitro experiments for testing their inhibition capability for antibacterial growth and enzymatic activity. Accordingly, four compounds displaying antibacterial growth inhibition above 40 % were determined as Candesartan cilexetil, Montelukast (sodium), Dronedarone (hydrochloride) and Thonzonium (bromide). In a second round of experiment, Candesartan cilexetil and Thonzonium displayed exceptionally high killing efficiencies on two bacterial strains of S. aureus (methicillin-sensitive and methicillin-resistant) with concentrations as low as 4 mu g/mL and 0.5 mu g/mL. Yet, their enzymatic assays were not in accordance with their killing effectiveness. Different inhibitory effects was observed for each compound in each enzymatic assay. A more effective target strategy would be to screen for drug compounds that woud inhibit a combination of glycolytic enzymes observed in the glycolytic pathway.Article Composite Hydrogel of Polyacrylamide/Starch as a Novel Amoxicillin Delivery System(Mdpi, 2024) Poyraz, Yagmur; Baltaci, Nisa; Hassan, Gana; Alayoubi, Oubadah; Uysal, Bengu Ozugur; Pekcan, OnderThis study investigates the development and characterization of a novel composite hydrogel composed of polyacrylamide (PAAm), starch, and gelatin for use as an amoxicillin delivery system. The optical properties, swelling behavior, and drug release profile of the composite hydrogel's were studied to evaluate its efficacy and potential applications. UV-visible spectroscopy was employed to determine the optical properties, revealing significant transparency in the visible range, which is essential for biomedical applications. The incorporation of starch and gelatin into the polyacrylamide matrix significantly enhanced the hydrogel's swelling capacity and biocompatibility. Studies on drug delivery demonstrated a sustained release profile of amoxicillin in simulated gastrointestinal fluids, which is essential for maintaining therapeutic levels for a prolonged amount of time. The results indicate that the composite hydrogel of PAAm/starch/gelatin has good swelling behavior, appealing optical characteristics, and a promising controlled drug release mechanism. These results point to this hydrogel's considerable potential as a drug delivery method, providing a viable path toward enhancing the medicinal effectiveness of amoxicillin and maybe other medications.Article Citation Count: 0Multimodal Language in Child-Directed Versus Adult-Directed Speech(SAGE Publications Ltd, 2024) Kandemir,S.; Özer,D.; Aktan-Erciyes,A.Speakers design their multimodal communication according to the needs and knowledge of their interlocutors, phenomenon known as audience design. We use more sophisticated language (e.g., longer sentences with complex grammatical forms) when communicating with adults compared with children. This study investigates how speech and co-speech gestures change in adult-directed speech (ADS) versus child-directed speech (CDS) for three different tasks. Overall, 66 adult participants (Mage = 21.05, 60 female) completed three different tasks (story-reading, storytelling and address description) and they were instructed to pretend to communicate with a child (CDS) or an adult (ADS). We hypothesised that participants would use more complex language, more beat gestures, and less iconic gestures in the ADS compared with the CDS. Results showed that, for CDS, participants used more iconic gestures in the story-reading task and storytelling task compared with ADS. However, participants used more beat gestures in the storytelling task for ADS than CDS. In addition, language complexity did not differ across conditions. Our findings indicate that how speakers employ different types of gestures (iconic vs beat) according to the addressee’s needs and across different tasks. Speakers might prefer to use more iconic gestures with children than adults. Results are discussed according to audience design theory. © Experimental Psychology Society 2023.Article Citation Count: 0The Gtp-Tubulin Cap Is Not the Determinant of Microtubule End Stability in Cells(Amer Soc Cell Biology, 2024) Cassidy,A.; Farmer,V.; Arpağ,G.; Zanic,M.Microtubules are dynamic cytoskeletal polymers essential for cell division, motility, and intracellular transport. Microtubule dynamics are characterized by dynamic instability-the ability of individual microtubules to switch between phases of growth and shrinkage. Dynamic instability can be explained by the GTP-cap model, suggesting that a "cap" of GTP-tubulin subunits at the growing microtubule end has a stabilizing effect, protecting against microtubule catastrophe-the switch from growth to shrinkage. Although the GTP-cap is thought to protect the growing microtubule end, whether the GTP-cap size affects microtubule stability in cells is not known. Notably, microtubule end-binding proteins, EBs, recognize the nucleotide state of tubulin and display comet-like localization at growing microtubule ends, which can be used as a proxy for the GTP-cap. Here, we employ high spatiotemporal resolution imaging to compare the relationship between EB comet size and microtubule dynamics in interphase LLC-PK1 cells to that measured in vitro. Our data reveal that the GTP-cap size in cells scales with the microtubule growth rate in the same way as in vitro. However, we find that microtubule ends in cells can withstand transition to catastrophe even after the EB comet is lost. Thus, our findings suggest that the presence of the GTP-cap is not the determinant of microtubule end stability in cells.Article Citation Count: 0The International Climate Psychology Collaboration: Climate Change-Related Data Collected From 63 Countries(Nature Portfolio, 2024) Doell, Kimberly C.; Todorova, Boryana; Vlasceanu, Madalina; Coleman, Joseph B. Bak; Pronizius, Ekaterina; Schumann, Philipp; Van Bavel, Jay J.Climate change is currently one of humanity's greatest threats. To help scholars understand the psychology of climate change, we conducted an online quasi-experimental survey on 59,508 participants from 63 countries (collected between July 2022 and July 2023). In a between-subjects design, we tested 11 interventions designed to promote climate change mitigation across four outcomes: climate change belief, support for climate policies, willingness to share information on social media, and performance on an effortful pro-environmental behavioural task. Participants also reported their demographic information (e.g., age, gender) and several other independent variables (e.g., political orientation, perceptions about the scientific consensus). In the no-intervention control group, we also measured important additional variables, such as environmentalist identity and trust in climate science. We report the collaboration procedure, study design, raw and cleaned data, all survey materials, relevant analysis scripts, and data visualisations. This dataset can be used to further the understanding of psychological, demographic, and national-level factors related to individual-level climate action and how these differ across countries.Article Citation Count: 7On the Uniqueness of Epidemic Models Fitting a Normalized Curve of Removed Individuals(Springer Verlag, 2015) Bilge,A.H.; Samanlioglu,F.; Ergonul,O.The susceptible-infected-removed (SIR) and the susceptible-exposed-infected-removed (SEIR) epidemic models with constant parameters are adequate for describing the time evolution of seasonal diseases for which available data usually consist of fatality reports. The problems associated with the determination of system parameters starts with the inference of the number of removed individuals from fatality data, because the infection to death period may depend on health care factors. Then, one encounters numerical sensitivity problems for the determination of the system parameters from a correct but noisy representative of the number of removed individuals. Finally as the available data is necessarily a normalized one, the models fitting this data may not be unique. We prove that the parameters of the (SEIR) model cannot be determined from the knowledge of a normalized curve of “Removed” individuals and we show that the proportion of removed individuals, R(t), is invariant under the interchange of the incubation and infection periods and corresponding scalings of the contact rate. On the other hand we prove that the SIR model fitting a normalized curve of removed individuals is unique and we give an implicit relation for the system parameters in terms of the values of (Formula presented.) and (Formula presented.), where Rf is the steady state value of R(t) and Rm and (Formula presented.) are the values of R(t) and its derivative at the inflection point tm of R(t). We use these implicit relations to provide a robust method for the estimation of the system parameters and we apply this procedure to the fatality data for the H1N1 epidemic in the Czech Republic during 2009. We finally discuss the inference of the number of removed individuals from observational data, using a clinical survey conducted at major hospitals in Istanbul, Turkey, during 2009 H1N1 epidemic. © 2014, Springer-Verlag Berlin Heidelberg.Article Citation Count: 9Women's Shelters in Turkey: A Qualitative Study on Shortcomings of Policy Making and Implementation(2013) Diner,C.; Toktaş,Ş.Despite a long history of women's movements and policy-making efforts to ameliorate women's status in Turkey, the number and quality of women's shelters are far from sufficient. This article aims to reveal the shortcomings of shelter policy through the lens of those "at work" on this important social issue using a qualitative research design. Forty semistructured in-depth interviews were conducted with municipal administrative officials, state social workers, and employees of civil society organizations that run shelters. The research findings reveal that there is a lack of effective authority that has the willpower to combat violence against women, and that it is difficult to keep shelters secure in a patriarchal society away from the male gaze. Furthermore, results indicate that there has been an erosion of social services provided by the state. © The Author(s) 2013.Article Citation Count: 6The Prevalence of Microalbuminuria and Relevant Cardiovascular Risk Factors in Turkish Hypertensive Patients(2011) Kozan,Ö.; Özcan,E.E.; Sancaktar,O.; Kabakci,G.; Sözcüer,A.H.; Kerpeten,A.; Tartan,Z.Objectives: A growing body of data illustrates the importance of microalbuminuria (MAU) as a strong predictor of cardiovascular risk in the hypertensive population. The present study was designed to define the prevalence of MAU and associated cardiovascular risk factors among Turkish hypertensive outpatients. Study design: Representing the Turkish arm of the multinational i-SEARCH study involving 1,750 sites in 26 countries around the world, a total of 1,926 hypertensive patients from different centers were included in this observational and cross-sectional survey study. Patients with reasons for a false-positive MAU test were excluded. The prevalence of MAU was assessed using a dipstick test, and patients were inquired about comorbidities, comedication, and known cardiovascular risk factors. Results: The overall prevalence of MAU was 64.7% and there was no difference between genders. Most of the patients (82.5%) had uncontrolled hypertension, 35.6% had dyslipidemia, and 35.5% had diabetes, predominantly type 2. Almost one-third of the patients (26.4%) had at least one cardiovascular-related comorbidity, with 20.3% having documented coronary artery disease (CAD). Almost all patients (96.8%) had one or more risk factors for cardiovascular disease in addition to hypertension, including family history of myocardial infarction or CAD, diabetes, dyslipidemia, lack of physical exercise, and smoking. A trend towards higher MAU values in the presence of CAD was determined. Conclusion: Microalbuminuria tests should be routinely used as a screening and monitoring tool for the assessment of subsequent cardiovascular morbidity and mortality among hypertensive patients. © 2011 Turkish Society of Cardiology.Article Citation Count: 7Gastrointestinal: Epiploic appendagitis(Blackwell Publishing, 2005) Kantarci,M.; Duran,C.; Sirvanci,M.[No abstract available]Editorial Citation Count: 0Article Citation Count: 3Relationship Between Dyslipidemia, C-Reactive Protein and Serological Evidence of Chlamydia Pneumoniae in Turkish Patients With Coronary Artery Diseases(2004) Turkoglu,C.; Sonmez,E.; Aydinli,A.Relationship between dyslipidemia, C-Reactive Protein (CRP) and serological evidence of Chlamydia pneumoniae was investigated in a Turkish population with coronary artery disease. This prospective, randomized, blinded study was carried out in Florence Nightingale Hospital which is affiliated to Kadir Has University, Medical Faculty. Thirty-two patients with acute coronary artery diseases (ACAD), 32 patients with chronic coronary artery diseases (CCAD) and 26 healthy controls (HC) were included in the study. We detected serum concentrations of C. pneumoniae IgG, IgA and IgM by ELISA method. We measured total cholesterol, trigliseride, LDL and HDL- cholesterol levels to determine dyslipidemia which was defined as total cholesterol >200 mg/dL, trigliserid > 150 mg/dl, LDL >130 mg/dL, HDL <45 mg/dL. CRP levels were also measured. Seropositivity to C. pneumoniae IgG was 84.3%, 100% and 65.3%; seropositivity to IgA was 9.3%, 6.2%, and 3.8%; and seropositivity to IgM was 12.5%, 15.3%, and 15.4% in patients with ACAD, CCAD and HC, respectively. Dyslipidemia was found as 93.7%, 78.1% and 0% of patients with ACAD, CCAD and HC, respectively. CRP level was high in all patients (ACAD, CCAD) but not in healthy controls. As a conclusion, we found a significant association between seropositivity to C. pneumoniae IgG and dyslipidemia and CRP levels in ACAD and CCAD patients (p<0.05). C. pneumoniae IgG antibodies should be evaluated together with serum lipids and CRP levels in patients with ACAD and CCAD in Turkish population. This may help clinicians in treatment of C. pneumoniae infection and decrease the risk of coronary artery diseases.Article Citation Count: 75Simvastatin Induces Proliferation Inhibition and Apoptosis in C6 Glioma Cells Via C-Jun N-Terminal Kinase(2004) Koyuturk,M.; Ersoz,M.; Altiok,N.The lipid-lowering drugs, statins, induce apoptosis in a variety of tumor cells. Here we investigated the apoptotic effect of the lipophilic statin, simvastatin, in C6 glioma cells and the underlying effects on intracellular signal transduction. Simvastatin inhibited cell proliferation totally after 20 h of treatment as shown by the decrease in proliferating cell nuclear antigen expression in the nucleus. Subsequently, simvastatin caused apoptotic cell death by shrinkage of cytoplasm and condensation of chromatin, and DNA fragmentation. The features of apoptosis were visible only after 48 h of treatment, possibly reflecting a requirement for cell commitment to growth arrest. In immunocytochemical and immunoblotting experiments we have shown that simvastatin markedly increased the phosphorylation of ATF-2 and c-jun in the nucleus of the C6 glioma cells at early time points which was preserved even 24 h after treatment. In contrast, activities of protein kinases Erk1/2 and AKT in the cell survival pathway remained unchanged throughout the treatment. Selective inhibitor of JNK, but not p38 kinase, reduced simvastatin-induced cell death and ATF-2 and c-jun phosphorylation suggesting that JNK-dependent activation of ATF-2 and c-jun may play an important role in simvastatin-induced proliferation inhibition and apoptosis in C6 glioma cells. These observations suggest that statins may have clinical significance in the prevention of glial tumors beyond their cholesterol-lowering effect and JNK may be a rational target for sensitizing glioma cells to chemotherapeutic agents. © 2004 Elsevier Ireland Ltd. All rights reserved.Article Citation Count: 17Corneal Ring Segments (intacs) for the Treatment of Asymmetrical Astigmatism of the Keratoconus. Follow-Up After 2 Years;(2003) Tunc,Z.; Deveci,N.; Sener,B.; Bahcecioglu,H.Objective: To evaluate the use of corneal ring segments (INTACS) for the treatment of asymmetrical astigmatism in keratoconus. Material and methods: This prospective study involved nine eyes of seven patients who were operated on between December 1998 and June 2000. A case of keratoconus with opacified cornea was excluded from this study. The patients chosen were contact lens-intolerant. The surgical intervention was carried out under topical anesthesia. The INTACS (Addition Technology) corneal ring insert was inserted approximately 68% of the peripheral corneal depth and was centered to the cone of the cornea. Results: No intraoperative complications occurred. We noted a flattening of the central cornea and a decrease in irregular astigmatism for all patients. Mean preoperative uncorrected visual acuity was less than 1/10. Postoperatively two eyes had an uncorrected visual acuity of 10/10, seven eyes showed an improvement from an uncorrected visual acuity of 2/10 to 7/10. Conclusion: We have observed that the flattening effect of INTACS inserts on the soft corneal keratoconic tissue and on the high astigmatic tissue seems greater than that produced in normal cornea. Implantation of INTACS resulted in a significant reduction in asymmetrical astigmatism of the keratoconus.Article Citation Count: 6The Use of Stentless Valves for Root Replacement During Repair of Ascending Aortic Aneurysms With Aortic Valve Regurgitation(2002) Akpinar,B.; Güden,M.; Aytekin,S.; Sanisoglu,I.; Sagbas,E.; Özbek,U.; Bayramoglu,Z.Background: Early and mid-term results of stentless valves for the treatment of ascending aortic aneurysm (AAA) were evaluated in a retrospective manner. Material and Methods: During a four-year period, 26 patients with ascending aortic aneurysms and aortic valve insufficiency underwent a total root replacement procedure using a stentless "Freestyle" valve (Medtronic Inc., Minneapolis MN). Mean age was 71 ± 4 years (range 66 to 79 years). Eight patients were in NYHA Class 2, 13 in Class 3, and 5 in Class 4. Cardiopulmonary bypass (CPB) was begun with femoral artery-right atrium (two-stage) cannulation in all cases but four, in which the right axillary artery was used. Myocardial protection was established by retrograde, cold-blood cardioplegia and direct antegrade blood cardioplegia from the right coronary ostium. The left ventricle outflow tract was constructed by using 2-0 ticron sutures and incorporating a pericardial strip in between. Coronary buttons were sewn to the xenograft with 6-0 polypropylene sutures. Meanwhile, the patient was cooled down to 18 degrees nasopharyngeal temperature and the distal anastomosis with the proximal arch was performed with a Dacron graft under total circulatory arrest (TCA), using 4-0 polypropylene sutures. During rewarming, the connection between the Freestyle valve and the Dacron graft was performed. Results: Ischemic time was 91 ± 11 minutes and TCA time was 9 ± 4 minutes. Operative mortality was zero, and there was one 30-day mortality (3.8%). At discharge, all 25 patients had a functional valve with low transvalvular gradients. Patients were followed for a mean period of 15 months, with one patient being lost to follow-up and one patient dying of non-cardiac causes. Follow-up was 97% complete, and echocardiographic control during the follow-up period revealed competent valves with gradients comparable to those at discharge. Two patients were screened with electron beam tomography (EBT) three years after the operation and there was no sign of wall or leaflet calcification. At the end of the 15 months (mean) follow-up, the functional capacity of the patients had improved significantly (p <0.05). Conclusions: Our early results suggest that use of the Freestyle valve in conjunction with a Dacron tube graft can be a good alternative for patients over 65 years of age who present with ascending aortic aneurysm with aortic valve insufficiency.Article Citation Count: 10Comparison of Intraoperative Transit-Time Flow Measurement With Early Postoperative Magnetic Resonance Flow Mapping: in Off-Pump Coronary Artery Surgery(2003) Sanisoglu,I.; Guden,M.; Balci,C.; Sagbas,E.; Duran,C.; Akpinar,B.The purpose of this prospective study was to evaluate graft patency of off-pump coronary artery surgery intraoperatively by transit-time flow measurement and to compare this technique with postoperative magnetic resonance flow mapping. Twenty patients (13 men and 7 women; mean age, 67.9 ± 7.6 yr) underwent off-pump coronary artery surgery. Intraoperative transit-time flow measurement of grafts was performed measuring maximum, minimum, and mean flows. For each graft, the pulsatile index was calculated by dividing the difference between the maximum and the minimum flow by the mean flow. In the early postoperative period (1st week), magnetic resonance flow mapping was performed using phase contrast flow quantification. Mean intraoperative flow values and mean magnetic resonance flow mapping values were compared. At the same postoperative session, contrast-enhanced magnetic resonance angiography was performed to evaluate graft patency. In 20 patients, a total of 49 coronary graft flows were assessed with intraoperative transit-time flow measurement and postoperative magnetic resonance flow mapping. Upon comparison, there was a strong correlation between techniques, with stable and statistically significant differences between the intraoperative and postoperative flow mapping values. One saphenous vein graft was revised intraoperatively, due to graft failure. Our data suggest that the combined use of intraoperative transit-time flow measurement and postoperative magnetic resonance flow analysis has a potential role in the assessment of graft patency in off-pump coronary artery surgery, although more study is required.
