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Öğe Comparison of novel Martin/Hopkins and sampson equations for calculation of low-density lipoprotein cholesterol in diabetic patients(ARQUIVOS BRASILEIROS CARDIOLOGIA, 2022) Naser, Abdulrahman; Isgandarov, Khagani; Güvenç, Tolga Sinan; Güvenç, Rengin Çetin; Şahin, MüslümBackground: The accurate determination of low-density lipoprotein cholesterol (LDL-C) is important to reach guidelinere-commended LDL-C concentrations and to reduce adverse cardiovascular outcomes in diabetic patients. The commonly used Friedewald equation (LDL-Cf), gives inaccurate results in diabetic patients due to accompanying diabetic dyslipidemia. Recently two new equations - Martin/Hopkins (LDL-Cmh) and Sampson (LDL-Cs) - were developed to improve the accuracy of LDL-C estimation, but data are insufficient to suggest the superiority of one equation over the other one. Objective: The present study compared the accuracy and clinical usefulness of novel Martin/Hopkins and Sampson equations in diabetic patients. Methods: This study included 402 patients with diabetes. Patients' cardiovascular risk and LDL-C targets were calculated per European guidelines. Calculated LDL-Cmh, LDL-Cs, and LDL-Cf concentrations were compared with direct LDL-C concentration (LDL-Cd) to test agreement between these equations and LDL-Cd. A p-value <0.05 was accepted as statistically significant. Results: Both LDL-Cmh and LDL-Cs had a better agreement with LDL-Cd as compared to LDL-Cf, but no statistical differences were found among novel equations for agreement with LDL-Cd (Cronbach's alpha 0.955 for both, p=1). Likewise, LDL-Cmh and LDL-Cs showed a similar degree of agreement with LDL-Cd in determining whether a patient was in a guideline-recommended LDL-C target (96.3% for LDL-Cmh and 96.0% for LDL- Cs), which were marginally better than LDL-Cf (94.6%). In patients with a triglyceride concentration >400 mg/dl, agreement with LDL-Cd was poor, regardless of the method used. Conclusion: Martin/Hopkins and Sampson's equations show a similar accuracy for calculating LDL-C concentrations in patients with diabetes, and both equations were marginally better than the Friedewald equation.Öğe Formulating and characterizing an exosome-based dopamine carrier system(Jove, 2022) Naser, Abdulrahman; Isgandarov, Khagani; Güvenç, Tolga Sinan; Ekmekçi, Ahmet; Güvenç, Rengin Çetin; Şahin, Müslüm; Gündüz, Sabahattin; Şahin, MüslümExosomes between 40 and 200 nm in size constitute the smallest subgroup of extracellular vesicles. These bioactive vesicles secreted by cells play an active role in intercellular cargo and communication. Exosomes are mostly found in body fluids such as plasma, cerebrospinal fluid, urine, saliva, amniotic fluid, colostrum, breast milk, joint fluid, semen, and pleural acid. Considering the size of exosomes, it is thought that they may play an important role in central nervous system diseases because they can pass through the blood-brain barrier (BBB). Hence, this study aimed to develop an exosome-based nanocarrier system by encapsulating dopamine into exosomes isolated from Wharton's jelly mesenchymal stem cells (WJ-MSCs). Exosomes that passed the characterization process were incubated with dopamine. The dopamine-loaded exosomes were recharacterized at the end of incubation. Dopamine-loaded exosomes were investigated in drug release and cytotoxicity assays. The results showed that dopamine could be successfully encapsulated within the exosomes and that the dopamine-loaded exosomes did not affect fibroblast viability.Öğe Lack of right ventricular hypertrophy is associated with right heart failure in patients with left ventricular failure(Springer, 2022) Naser, Abdulrahman; Isgandarov, Khagani; Güvenç, Tolga Sinan; Ekmekçi, Ahmet; Gündüz, Sabahattin; Güvenç, Rengin Çetin; Şahin, MüslümPresence of right heart failure (RHF) is associated with a worse prognosis in patients with left ventricular failure (LVF). While the cause of RHF secondary to LVF is multifactorial, an increased right ventricular (RV) afterload is believed as the major cause of RHF. However, data are scarce on the adaptive responses of the RV in patients with LVF. Our aim was to understand the relationship of right ventricular hypertrophy (RVH) with RHF and RV systolic and diastolic properties in patients with LVF. 55 patients with a left ventricular ejection fraction of 40% or less were included in the present study. A comprehensive two-dimensional transthoracic echocardiographic examination was done to all participants. 12 patients (21.8%) had RHF, and patients with RHF had a signifcantly lower right ventricular free wall thickness (RVFWT) as compared to patients without RHF (5.3±1.7 mm vs. 6.6±0.9 mm, p=0.02) and the diference remained statistically signifcant after adjusting for confounders (?x?:1.34 mm, p=0.002). RVFWT had a statistically signifcant correlation with tricuspid annular plane systolic excursion (r=0.479, p<0.001) and tricuspid annular lateral systolic velocity (r=0.360, p=0.007), but not with the indices of the RV diastolic function. None of the patients with concentric RVH had RHF, while 22.2% of patients with eccentric RVH and 66.7% of patients without RVH had RHF (p<0.01 as compared to patients with concentric RVH). In patients with left ventricular systolic dysfunction, absence of RVH was associated with worse RV systolic performance and a signifcantly higher incidence of RHFÖğe Thrombolysis in myocardial infarction risk index predicts one-year mortality in patients with heart failure: an analysis of the SELFIE-TR study(KARGER, 2022) Güvenç, Rengin Çetin; Güvenç, Tolga Sinan; Ural, Dilek; Cavusoglu, Yuksel; Yilmaz, Mehmet BirhanObjective: Predicting outcomes is an essential part of evaluation in patients with heart failure (HF). While there are multiple individual laboratory and imaging variables, as well as risk scores available for this purpose, they are seldom useful during the initial evaluation. In this analysis, we aimed to understand predictive usefulness of Thrombosis in Myocardial Infarction Risk Index (TIMI-RI), a simple index that is calculated at bedside using three commonly available variables, using data from a multicenter HF registry. Subjects and Methods: A total of 728 patients from 23 centers were included to this analysis. Data on hospitalizations and mortality were collected by direct interviews, phone calls and electronic databases. TIMI-RI was calculated as defined before. Patients were divided into three equal tertiles to perform analyses. Results: Rehospitalization for HF was significantly higher in patients within the 3rd tertile, and 33.5% of patients within the 3rd tertile were dead within one-year follow up as compared to 14.5% of patients within the 1st tertile and 15.6% patients within the 2nd tertile (p<0.001, log-rank p<0.001 for pairwise comparisons on survival analysis). A TIMI-RI higher than 33 had a negative predictive value of 84.8% and a positive predictive value of 33.8% for prediction of one-year mortality. This predictive usefulness was independent of other demographic, examination and clinical variables (OR:1.74, 95%CI:1.05-2.86, p=0.036). Conclusion: TIMI-RI is a simple index that predicts one-year mortality in patients with HF, and it could be useful for rapid evaluation and triage of HF patients at the time of initial contact.
