Acıbadem Üniversitesi Açık Erişim Sistemi
Not a member yet
2603 research outputs found
Sort by
Rescue IVM of Denuded GV- and MI-Stage Oocytes of Premenopausal Rats with Oncostatin M, Insulin-like Growth Factor I, and Growth Hormone
No full textImmature oocytes are retrieved and matured through in vitro maturation (IVM). Maturation, fertilization rates, and embryo development via IVM are all lower than those found in vitro fertilization (IVF) cycles. We investigated the effects of oncostatin M (OSM), insulin-like growth factor-1 (IGF-I), and growth hormone (GH) in rescue IVM. A total of 111 germinal vesicle (GV) and 17 metaphase I (MI) oocytes were obtained after conventional IVF from 28 female Wistar albino rats. Denuded immature oocytes were cultured in maturation medium supplemented with OSM, IGF-1, or GH. The quantities of metaphase II (MII) oocytes matured from the GV stage were 17 of 30 (56.6\%), 15 of 28 (53.5\%), 10 of 30 (33.3\%), and 7 of 23 (30.3\%), in control, OSM, IGF-I, and GH groups, respectively. Maturation rates in control and OSM groups were higher than those in IGF-I and GH groups (p = 0.001). The quantities of MII oocytes matured from MI stage were 7 of 7 (100\%), 4 of 4 (100\%), 1 of 1 (100\%), and 1 of 5 (20\%) in control, OSM, IGF-I, and GH groups, respectively. Maturation rates from MI to MII stages in control, OSM, and IGF-I groups were higher than those in the GH group (p = 0.004). Acceptable maturation rates are observed with OSM in rat oocytes in rescue IVM.8AUG1
Robotic Cardiac Surgery in Europe: Status 2020
No full textBackgroundEuropean surgeons were the first worldwide to use robotic techniques in cardiac surgery and major steps in procedure development were taken in Europe. After a hype in the early 2000s case numbers decreased but due to technological improvements renewed interest can be noted. We assessed the current activities and outcomes in robotically assisted cardiac surgery on the European continent. MethodsData were collected in an international anonymized registry of 26 European centers with a robotic cardiac surgery program. ResultsDuring a 4-year period (2016-2019), 2,563 procedures were carried out {[}30.0\% female, 58.5 (15.4) years old, EuroSCORE II 1.56 (1.74)], including robotically assisted coronary bypass grafting (n = 1266, 49.4\%), robotic mitral or tricuspid valve surgery (n = 945, 36.9\%), isolated atrial septal defect closure (n = 225, 8.8\%), left atrial myxoma resection (n = 54, 2.1\%), and other procedures (n = 73, 2.8\%). The number of procedures doubled during the study period (from n = 435 in 2016 to n = 923 in 2019). The mean cardiopulmonary bypass time in pump assisted cases was 148.6 (63.5) min and the myocardial ischemic time was 88.7 (46.1) min. Conversion to larger thoracic incisions was required in 56 cases (2.2\%). Perioperative rates of revision for bleeding, stroke, and mortality were 56 (2.2\%), 6 (0.2 \%), and 27 (1.1\%), respectively. Median postoperative hospital length of stay was 6.6 (6.6) days. ConclusionRobotic cardiac surgery case numbers in Europe are growing fast, including a large spectrum of procedures. Conversion rates are low and clinical outcomes are favorable, indicating safe conduct of these high-tech minimally invasive procedures.JAN 20
Oligosarcomas, IDH-mutant are distinct and aggressive
No full textOligodendrogliomas are defined at the molecular level by the presence of an IDH mutation and codeletion of chromosomal arms 1p and 19q. In the past, case reports and small studies described gliomas with sarcomatous features arising from oligodendrogliomas, so called oligosarcomas. Here, we report a series of 24 IDH-mutant oligosarcomas from 23 patients forming a distinct methylation class. The tumors were recurrences from prior oligodendrogliomas or developed de novo. Precursor tumors of 12 oligosarcomas were histologically and molecularly indistinguishable from conventional oligodendrogliomas. Oligosarcoma tumor cells were embedded in a dense network of reticulin fibers, frequently showing p53 accumulation, positivity for SMA and CALD1, loss of OLIG2 and gain of H3K27 trimethylation (H3K27me3) as compared to primary lesions. In 5 oligosarcomas no 1p/19q codeletion was detectable, although it was present in the primary lesions. Copy number neutral LOH was determined as underlying mechanism. Oligosarcomas harbored an increased chromosomal copy number variation load with frequent CDKN2A/B deletions. Proteomic profiling demonstrated oligosarcomas to be highly distinct from conventional CNS WHO grade 3 oligodendrogliomas with consistent evidence for a smooth muscle differentiation. Expression of several tumor suppressors was reduced with NF1 being lost frequently. In contrast, oncogenic YAP1 was aberrantly overexpressed in oligosarcomas. Panel sequencing revealed mutations in NF1 and TP53 along with IDH1/2 and TERT promoter mutations. Survival of patients was significantly poorer for oligosarcomas as first recurrence than for grade 3 oligodendrogliomas as first recurrence. These results establish oligosarcomas as a distinct group of IDH-mutant gliomas differing from conventional oligodendrogliomas on the histologic, epigenetic, proteomic, molecular and clinical level. The diagnosis can be based on the combined presence of (a) sarcomatous histology, (b) IDH-mutation and (c) TERT promoter mutation and/or 1p/19q codeletion, or, in unresolved cases, on its characteristic DNA methylation profile.2FEB263-28114
Factors Affecting the Population of Mesenchymal Stem Cells in Adipose-Derived Stromal Vascular Fraction
No full textBackground: Recently, the adipose tissue-derived stromal vascular fraction has become the most popular source for obtaining mesenchymal stem cells because it is less expensive and is easier to perform than bone marrow concentrate harvesting. However, no study has investigated the factors affecting the mesenchymal stem cell population in adipose tissue derived stromal vascular fraction. Understanding the interaction of patient factors with the mesenchymal stem cell count and cell viability in adipose tissue-derived stromal vascular fraction could provide crucial information for surgeons to improve patient selection and outcomes.Aims: To evaluate the factors affecting the mesenchymal stem cell count, total cell count, and cell viability in adipose tissue-derived stromal vascular fraction.Study Design: Retrospective cross-sectional study.Methods: This study retrospectively reviewed the medical records of 30 patients who underwent liposuction to harvest adipose tissue - derived stromal vascular fraction at our stem cell center. Operative variables, such as lipoaspirate amount and donor areas from the stromal vascular fraction harvesting site, included the entire abdomen and lower abdomen. We recorded the mesenchymal stem cell population, cell viability, and cell count of stromal vascular fraction, and we analyzed the results to determine statistical significance.Results: The factors that were found to be significantly related are as followsbetween cell number and age (p=0.001) and amount of lipoaspirate (p<0.001)between cell viability and body mass index (p=0.005) and hypertension (p=0.047)and between coronary artery disease and mesenchymal stem cell counts (p = 0.028).Conclusion: The relationship of patient factors (age, body mass index, hypertension, and coronary artery disease) with cell viability and mesenchymal stem cell counts may be important for clinical applications. However, the effect of medications on these relationships should be investigated in larger studies.6NOV386-3923
MTHFR C677T mutation affects adipogenic differentiation abilities of human bone marrow-derived mesenchymal stem cells
No full textThe effects of 5,10-Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism on human bone marrow-derived mesenchymal stem cells (hBM-MSCs) viability, morphology, physiology and differentiation capacity were investigated in this study. For this purpose, primary hBM-MSCs with wild type (WT, C/C), heterozygote (HTZ, C/T) and homozygote (HMZ, T/T) for the MTHFR gene were obtained with ethical committee permission and donor informed. Mutations were detected using RFLP and Sanger sequencing methods from genomic DNA isolated from cells, colonization properties were investigated by CFU-F test and proliferative differences were investigated by MTT test. Adipogenic, osteogenic, and chondrogenic differentiation were induced to study changes in their differentiation potentials, and the results were statistically analyzed using one-way ANOVA with Graphpad Prism. A total of 13 donors were screened and there were no differences in the hBM-MSC markers and in vitro morphologies of the cells. While there were significant differences between WT and HTZ as a result of the CFU-F test, there were no significant differences in the MTT test alter 24 and 48 h. As a result of differentiation tests, it was found that adipogenic differentiation was significantly more in HMZ cells than WT cells. Osteogenic and chondrogenic differentiation results did not give statistically significant results. As a result of these experiments, adipogenic differentiation was found to be affected by the MTHFR genotype in hBM-MSCs.5375-3874
Hysteroscopy-Guided Natural Orifice Repair of Isthmocele
No full textIsthmocele can be defined as a hypoechoic field within the lower uterine segment, indicating a discontinuation of the myometrium at the uterine scar of a previous cesarean section. Postmenstrual spotting, pelvic pain, dysmenorrhea, dyspareunia, uterine rupture, cesarean scar pregnancy, and secondary infertility could be seen as the complications of existing isthmocele. Such defects are prevalent with the increasing number of cesarean deliveries. A 39-year-old woman who had three prior cesarean sections complaining irregular uterine bleeding for 2 years was examined. A uterine scar defect was observed. A hysteroscopy-guided natural orifice approach was planned to repair the defect. The patient was discharged without any complication in her postoperative 6th h. She had no pain or irregular bleeding in her 2-week postoperative visit.2APR-JUN116-1181
Expansion to the Motion Sickness Susceptibility Questionnaire-Short Form: A Cross-Sectional Study
No full textBackground and Objectives: The primary objective of this study is to investigate the necessity of questioning virtual reality systems in the motion sickness susceptibility questionnaire (MSSQ)-short form. The secondary objective of this study is to determine the validity and reliability of the Turkish version of the MSSQ-short form, with proven validity and reliability. Subjects and Methods: In the questionnaire form, for which expert opinion was obtained to maintain linguistic equivalence, the virtual reality items were added to the questionnaire. The questionnaire was then administered to 297 individuals. The results were statistically analyzed with and without these virtual reality items for validity and reliability. Results: After the addition of the virtual reality items, the reliability of the questionnaire was found to be quite high (Cronbach's alpha r=0.912). The norm values between the original MSSQ-short form (12.9 +/- 9.9) and the Turkish MSSQ-short form (13.8 +/- 12.9) were found to be consistent. Conclusions: Motion sickness symptoms can occur not only during movement, but also with indirect stimulus. Our findings suggest that adding virtual reality items to the original form is important in long term practical applications. Our results show that the Turkish version of the original questionnaire is quite reliable. Submission of the MSSQ-short form in Turkish will be useful for documentation and will also encourage further research in this area.2APR76-822
Self-perspective Versus Caregiver-perspective on Cognitive Impairment at Different Stages of the Alzheimer's Continuum
No full textObjective: To understand how the patients' and their study partners'/caregivers' perspectives on cognitive decline change at the subjective cognitive decline (SCD), mild cognitive impairment (MCI), and probable Alzheimer's disease (PRAD) stages of the Alzheimer's disease (AD) continuum. Materials and Methods: Twenty-three individuals with the diagnosis of SCD, 33 individuals with the diagnosis of MCI, and 17 individuals with the diagnosis of PRAD were included. A cognitive testing battery including the standardized mini-mental state examination (MMSE), digit span forward and backwards tests, and the semantic fluency test were administered to all patients. The cognitive function instrument (CFI) was used for the subjective assessment of cognitive decline. The same questions in the CFI were answered both by the patients (CFI-self report) and the study partners (CFI-partner report). Results: In the SCD and the MCI groups, the CFI-self report scores were higher than the CFI-partner report scores, whereas an opposite pattern was found in the PRAD group with higher CFI-partner report scores and lower CFI-self report scores. The CFI self report scores positively correlated with the MMSE scores in the PRAD group showing higher ratings in cognitively less impaired individuals, and vice versa. The CFI partner-report scores did not show a significant correlation with the MMSE scores in any of the groups, however a trend for a negative correlation was observed in the MCI group. Finally, the CFI-self report and partner report scores significantly correlated only in the MCI group. Conclusion: Report-based assessment of cognitive decline can be informative, particularly in the early stages of the AD continuum. However, the loss of insight in PRAD may mask the symptoms when the subjective cognitive assessment relies on the patients' perspective. The greatest concordance between the patients' and their partners' perspectives was evident in the MCI stage which represented a transitional period between SCD and PRAD.4DEC248-2532
Importance of oxidative stress in the evaluation of acute pulmonary embolism severity
No full textBackground Pulmonary embolism (PE) is a common and potentially life-threatening disorder. Our study was aimed to investigate whether oxidative stress markers can be used as clinical markers in the evaluation of acute PE (APE) severity. Methods 47 patients with objectively documented diagnosis of APE were recorded. Of these patients, 14 had low-risk PE, 16 had moderate-risk PE, and 17 had high-risk PE. 21 healthy subjects were also enrolled in this study. Ischemia-modified albumin (IMA), prooxidants-antioxidants balance (PAB), advanced protein oxidation products (AOPPs), and ferric reducing antioxidant power (FRAP) were measured as oxidative stress parameters to evaluate the role of oxidative stress. Results In the low-risk and moderate-risk APE groups, AOPPs and PAB levels were significantly higher and FRAP levels were significantly lower than those in the control group. AOPPs and IMA levels in the patients with high-risk PE were significantly higher than those in both the low-risk and moderate-risk APE patients. There was a significant correlation between levels of AOPPs and the levels of both IMA (r: 0.462, p < 0.001) and PAB (r:0.378, p < 0.005). Serum FRAP levels were negatively correlated with PAB (r:- 0.683, p < 0.001) and AOPPs levels (r:- 0,384, p < 0.001). There was also a significant positive correlation between the serum IMA and PAB levels. Conclusions We clearly demonstrated that reactive oxygen species formation is significantly enhanced in APE. IMA and AOPPs may be used as clinical markers in the evaluation of APE severity in clinical practice. However, further studies with larger patient populations and longer follow-up periods are required to confirm the mechanisms underlying these findings.1OCT 172
The alterations of blood-testis barrier in experimental testicular injury models
No full textThe blood-testis barrier is found between the Sertoli cells and divides the seminiferous tubule epithelium into basal and adluminal compartments. The germinal cell renewal, differentiation and cell cycle progression up to the preleptotene spermotocytes stage take place in the basal compartment, however, meiosis, spermiogenesis and spermiation take place in the adluminal compertment. The blood-testis barrier consists of tight junctions as well as ectoplasmic specialisations, desmosomes and gap junctions to create specific microenvironment for the completion of spermatogenesis to form spermatozoa. The blood-testis barrier is not a static ultrastructure, it undergoes extensive restructuring during the seminiferous tubule epithelial cycle of spermatogenesis to allow the transit of preleptotene spermotocytes at the blood-testis barrier from basal compartment towards the adluminal compartment. The functions of the blood-testis barrier include preventing the transport of biomolecules into the paracellular space, forming an immunological barrier, separating cellular processes during the spermatogenic epithelial cycle, and establishing the cellular polarity of the seminiferous tubule. However, various environmental conditions, chemotherapeutic agents, toxic substances and lifestyle have degenerative effects on blood-testis barrier, resulting in testicular damage, altered sperm parameters and ultimately male infertility. The alterations in morphological and molecular organization of blood-testis barrier in different experimentally induced testis injury models arc reviewed in this article.2249-2533