Synthesis and Labeling of Two Fibrin-Targeted Peptides (HYNICGPRPILE, HYNIC-GPKGAAD) Using Technetium-99m and In Vitro Evaluation of Fibrin Binding and Platelet Aggregation: Fibrin-targeted peptides for molecular imaging of thrombus

Early detection of thrombus and its location in the body are critical factors for the treatment of thrombosis related diseases. Fibrin is the main component of thrombus, abundant in all thrombi, and is not found in non-pathological conditions. The presence of fibrin in all types of thrombi and its low concentration in blood makes it a sensitive and specific target for imaging studies of thrombus. Fibrin also accumulates in malignant tumors. Thus, fibrin imaging can be used in oncology, atherosclerosis, and thrombosis-related pathologies such as pulmonary emboli and deep vein thrombosis. Different compounds such as antibodies, nanoparticles, and peptides have been studied for fibrin imaging. Among them, peptides are more attractive because of better pharmacokinetics, simple and cheap preparation, and better radiolabeling methods. In this study, two peptides (HYNIC-GPRPILE, HYNIC-GPKGAAD) designed to target fibrin were synthesized.  The peptides were identified by LC-MS. The stability and platelet aggregation of peptides were determined. Peptides were radiolabeled with 99mTc using HYNIC as chelating agent. The release of 99mTc and fibrin binding of radiopeptides were evaluated. Based on the results, peptides were stable in human plasma for at least 6 h and had no effect on platelet aggregation. Peptides were radiolabeled with pertechnetate at 80°C in 30 min. Radiochemical purity was over 95%. Radiopeptides were stable in human plasma and there was less than 5% release of 99mTc. The fibrin binding of radiopeptides was 70%>. Since peptides had no platelet binding activity, it can be concluded that binding of radiopeptides to fibrin is specific. HIGHLIGHTS Molecular imaging of fibrin used in oncology, atherosclerosis, and thrombosis related pathologies. Invasive early detection of thrombus using radiolabeled fibrin targeted peptides. Radiolabeling of peptides with 99mTc using HYNIC as chelating agent and EDDA and tricine as co-ligand. &nbsp

The effect of endocervical and catheter bacterial colonisation during in vitro fertilisation and embryo transfer (IVF-ET) on IVF success rate among asymptomatic women: a longitudinal prospective study

The adverse effects of bacterial contamination during in vitro fertilisation and embryo transfer (IVF-ET) have been studied previously. However, data on asymptomatic women with positive bacterial culture and their IVF outcome are lacking. This prospective longitudinal study was conducted on 74 women undergoing IVF-ET, of whom specimens from the endocervix and ET catheter were taken and sent to a laboratory for microbiological assessment. Then, patients were followed up for evaluation of chemical pregnancy (β-HCG > 25 mIU/mL) and clinical pregnancy (detected foetal heartbeat). The findings revealed that there was no significant difference in terms of biochemical (35.4% vs. 19.2%, p= .116) and clinical pregnancy rate (25.0% vs. 15.4%, p= .257) among ET catheter culture positive and negative women. This finding allows us to conclude that the positive culture in the absence of clinical signs of infection may not increase the risk of implantation failure.Impact Statement What is already known on this subject? There is growing evidence indicating that endometritis may decrease the endometrial receptiveness in in vitro fertilisation (IVF) cycles; however, there is a paucity of knowledge regarding IVF outcomes when the bacterial culture of embryo transfer (ET) catheter is positive. What the results of this study add? The present study demonstrates that positive ET catheter culture in asymptomatic women does not increase the risk of IVF failure. What the implications are of these findings for clinical practice and/or further research? Positive-culture, per se, may not be associated with poor IVF outcomes and further studies should be undertaken on this topic in various clinical settings using different protocols

COVID-19 and Cardiomyopathy: A Systematic Review

Background: Cardiomyopathies (CMPs) due to myocytes involvement are among the leading causes of sudden adolescent death and heart failure. During the COVID-19 pandemic, there are limited data available on cardiac complications in patients with COVID-19, leading to severe outcomes. Methods: We conducted a systematic search in Pubmed/Medline, Web of Science, and Embase databases up to August 2020, for all relevant studies about COVID-19 and CMPs. Results: A total of 29 articles with a total number of 1460 patients were included. Hypertension, diabetes, obesity, hyperlipidemia, and ischemic heart disease were the most reported comorbidities among patients with COVID-19 and cardiomyopathy. In the laboratory findings, 21.47% of patients had increased levels of troponin. Raised D-dimer levels were also reported in all of the patients. Echocardiographic results revealed mild, moderate, and severe Left Ventricular (LV) dysfunction present in 17.13, 11.87, and 10% of patients, respectively. Conclusions: Cardiac injury and CMPs were common conditions in patients with COVID-19. Therefore, it is suggested that cardiac damage be considered in managing patients with COVID-19