PubMed İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://gcris.khas.edu.tr/handle/20.500.12469/4466

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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, Onder
This 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.
Citation Count: 0
Multimodal language in child-directed versus adult-directed speech
(SAGE Publications Ltd, 2024) Özer, Demet; 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.
Citation Count: 0
The Gtp-Tubulin Cap Is Not the Determinant of Microtubule End Stability in Cells
(Amer Soc Cell Biology, 2024) Cassidy, Anna; Farmer, Veronica; Arpa, Goker; Zanic, Marija
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.
Citation Count: 0
The International Climate Psychology Collaboration: Climate change-related data collected from 63 countries
(2024) Doell,K.C.; Todorova,B.; Vlasceanu,M.; Bak Coleman,J.B.; Pronizius,E.; Schumann,P.; Van Bavel,J.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. © 2024. The Author(s).
Citation Count: 7
On the uniqueness of epidemic models fitting a normalized curve of removed individuals
(Springer Verlag, 2015) Bilge, Ayşe Hümeyra; Samanlıoğlu, Funda; 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.
Citation Count: 9
Women'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.
Citation Count: 6
The 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.
Citation Count: 7
Gastrointestinal: Epiploic appendagitis
(Blackwell Publishing, 2005) Kantarci,M.; Duran,C.; Sirvanci,M.
[No abstract available]
Citation Count: 3
Relationship 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.
Citation Count: 0
Metabolic syndrome and coronary heart disease;
(2004) Türkoǧlu,Ç.
[No abstract available]
Citation Count: 75
Simvastatin 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.
Citation Count: 17
Corneal 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.
Citation Count: 10
Comparison 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.
Citation Count: 6
The 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.
Citation Count: 3
Long-standing seroma after ultrasound-assisted liposuction
(Lippincott Williams and Wilkins, 2001) Aaolu,G.; Erol,O.
[No abstract available]
Citation Count: 18
Off-pump coronary artery bypass grafting with use of the octopus 2 stabilization system.
(2000) Akpinar,B.; Güden,M.; Sagbas,E.; Sanisoglu,I.; Aytekin,V.; Bayindir,O.
BACKGROUND: The treatment of coronary artery disease has evolved rapidly over the last two decades. The gold standard of surgical revascularization, the on-pump coronary artery bypass graft, has been challenged by the development of percutaneous transluminal coronary angioplasty. Our experience with the alternative of the off-pump ("beating heart") coronary artery bypass (OPCAB) technique during a period of 18 months suggests that OPCAB avoids the complications of cardiopulmonary bypass and offers patients the benefit of long-term graft patency that greatly exceeds that of current endovascular technologies. METHODS: The early results of 126 OPCAB procedures performed through a medial sternotomy incision during a period of 18 months were evaluated. There were 80 male and 46 female patients, with a mean age of 69 +/- 4.3 years. Emergency cases and reoperations were not included. A total of 268 anastomoses were performed, with a mean number of 2.12 anastomoses per patient. Conduits used, with their percentage of use, were: left internal thoracic artery (LITA) (100%), right internal thoracic artery (11.1%), greater saphenous vein (84%), and radial artery (31%). In 72% of the cases, off-pump surgery was chosen because of patient risk factors such as atherosclerotic aortic disease, previous cerebrovascular accident or carotid artery disease, renal dysfunction, malignancy or poor left ventricular function. RESULTS: There was no operative mortality. One-month postoperative mortality was three patients (2.3%). Two died because of mesenteric ischemia, and the other death was due to cardiac failure. Seventy-one patients had a control angiogram before discharge. The patency of LITA anastomosis was 100% while overall patency rate was 95%. In 43 patients for whom an angiogram could not be performed, a Thallum 201 stress test was performed three months postoperatively. Thirty-eight patients had a normal test while five patients showed signs of ischemia. These patients had a control angiogram: in four patients anastomoses were patent, but in one patient there was a severe narrowing of a venous anastomosis to the distal right coronary artery (RCA) which was corrected with angioplasty. In the whole series eight patients (6.3%) refused to have any control examination. CONCLUSIONS: Our early results suggest that off-pump CABG with Octopus 2 (Medtronic, Inc., Minneapolis, MN) can be a good alternative in high risk patients who need multiple vessel revascularization.
Citation Count: 0
The Statistics of q-Statistics
(Mdpi, 2024) Eroğlu, Deniz; Boghosian, Bruce M.; Borges, Ernesto P.; Tirnakli, Ugur
Almost two decades ago, Ernesto P. Borges and Bruce M. Boghosian embarked on the intricate task of composing a manuscript to honor the profound contributions of Constantino Tsallis to the realm of statistical physics, coupled with a concise exploration of q-Statistics. Fast-forward to Constantino Tsallis' illustrious 80th birthday celebration in 2023, where Deniz Eroglu and Ugur Tirnakli delved into Constantino's collaborative network, injecting renewed vitality into the project. With hearts brimming with appreciation for Tsallis' enduring inspiration, Eroglu, Boghosian, Borges, and Tirnakli proudly present this meticulously crafted manuscript as a token of their gratitude.
Citation Count: 0
Near-Infrared Triggered Degradation for Transient Electronics
(Amer Chemical Soc, 2024) Istıf, Emın; Ali, Mohsin; Ozuaciksoz, Elif Yaren; Morova, Yagiz; Beker, Levent
Electronics that disintegrate after stable operation present exciting opportunities for niche medical implant and consumer electronics applications. The disintegration of these devices can be initiated due to their medium conditions or triggered by external stimuli, which enables on-demand transition. An external stimulation method that can penetrate deep inside the body could revolutionize the use of transient electronics as implantable medical devices (IMDs), eliminating the need for secondary surgery to remove the IMDs. We report near-infrared (NIR) light-triggered transition of metastable cyclic poly-(phthalaldehyde) (cPPA) polymers. The transition of the encapsulation layer is achieved through the conversion of NIR light to heat, facilitated by bioresorbable metals, such as molybdenum (Mo). We reported a rapid degradation of cPPA encapsulation layer about 1 min, and the rate of degradation can be controlled by laser power and exposure time. This study offers a new approach for light triggerable transient electronics for IMDs due to the deep penetration depth of NIR light through to organs and tissues.
Citation Count: 0
Children's questions and teachers' responses about COVID-19 in Türkiye and the US
(Public Library Science, 2024) Unlutabak, Burcu; Trujillo Hernandez, Graciela; Velioglu, Ilayda; Menendez, David; Rosengren, Karl S.
Question-asking is a crucial tool for acquiring information about unseen entities, such as viruses; thus, examining children's questions within the context of COVID-19 is particularly important for understanding children's learning about the coronavirus. The study examined 3-12-year-old children's questions and teachers' responses about the COVID-19 pandemic in T & uuml;rkiye, a non-Western developing context, and the United States, a Western cultural context. A total of 119 teachers from T & uuml;rkiye and 95 teachers from the US participated in the study. Teachers completed an online survey consisting of a demographic form and a questionnaire asking them to report three questions about COVID-19 asked by children in their classrooms and their responses to these questions. We analyzed children's questions and teachers' responses for their type and content and examined demographic factors associated with children's questions and teachers' responses. Consistent with the literature, children from T & uuml;rkiye asked fewer explanation-seeking (i.e., why/how) questions than children from the United States. Children asked questions about viruses and precautions. Teachers responded to children's questions realistically in both countries. The findings have important implications for how children gain knowledge from teachers when discussing health, disease, and virus topics in two countries.
Citation Count: 7
The use of stentless valves for root replacement during repair of ascending aortic aneurysms with aortic valve regurgitation
(Forum Multimedia Publishing, Llc, 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 insuffiency 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 lea et 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.

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