Tıp Fakültesi / Faculty of Medicine
Permanent URI for this collectionhttps://hdl.handle.net/11727/1403
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Item User Verification of Abbott Alinity HQ Hematology Analyzer(2023) Bayraktar, Nilufer; Topcu, Deniz Ilhan; 0000-0002-1219-6368; 0000-0002-7886-3688; E-3717-2019; Y-8758-2018Objectives This study aims to evaluate the performance characteristics of the Alinity HQ hematology analyzer in a routine laboratory setting.Methods In the study, precision (short-term and long-term precision), accuracy (method comparison with Abbott Cell Dyn Ruby and estimation of bias), confirmation of a background (Limit of Blank, LoB), and carry-over were used to evaluate the performance of Alinity HQ as recommended by ICSH, CLSI guidelines EP15-A3, EP09, EP17A2, and H26-A2. Acceptance criteria were based on manufacturer technical specifications and the EFLM Biological Variation Database.Results According to the short-term precision results, except for mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentration (MCHC), all measurements exhibited coefficient variations (CV) lower than their verification limits. Basophil, eosinophil, and monocyte counts, as well as mean corpuscular hemoglobin (MCH), MCHC, and red cell distribution width standard deviation (RDW-SD), did not meet the allowable imprecision criteria for the long-term precision study. The estimated bias for all analytes was within verification limits. However, the method comparison study showed concentration-dependent variations for MCHC, MCH, and mean platelet volume (MPV) parameters. Furthermore, the correlation of parameters between Alinity HQ and Cell Dyn Ruby ranged from 0.46 to 1.00. The LoB and carry-over studies demonstrated satisfactory performance for the Alinity HQ analyzer.Conclusions Although some parameters had higher CVs than expected and concentration-dependent bias, the overall analytical performance of Alinity HQ was found to be satisfactory. Alinity HQ is an accurate, highly precise analyzer with good analytical performance, suitable for high-volume laboratories.Item Effects of Pesticides on Testes at Ultrastructural and Hormonal Levels(2023) Unlukal, Nejat; Karabay, Gulten; Dagdeviren, Attila; Bayraktar, Nilufer; Guvercin, Ayse Canan Yazici; Tekindal, Mustafa Agah; 0000-0002-8107-4882Aim: Endocrine disruptors damage the functions of hormones in the body by imitating or blocking them. They and their metabolites change hormone levels and functions in the body. Pesticides constitute a significant group of endocrine disruptors. It is known that Profenofos, and 4-chloro-2-methylphenoxyacetic acid (MCPA) have negative effects on male genital system. However, studies about the effect on ultrastructural size are limited. Therefore, it is intended to compare the effect of MCPA and Profenofos on the ultrastructural level of the testes. Material and Methods: There were three groups in the study (control, Profenofos, MCPA), each of which included ten fourteen-week-old male rats. Electron microscopy and biochemical investigation were performed on the excluded tissues of the testes. Results: In histopathologic investigations, spermatogenesis was healthy in the control group. Structural degenerations were observed on spermatogenic cells and Sertoli cells in the profenofos group. The gaps among spermatogenetic cells, cellular degeneration (i.e. structural damage) in the MCPA group was more obvious than in the Profenofos group. Considering the biochemical results, a significant decrease in testosterone level was observed in the animals receiving both profonefos and MCPA. Discussion: Profenofos and MCPA prevent the healthy continuation of spermatogenesis and therefore may cause infertility.Item Searching For The Urine Osmolality Surrogate: An Automated Machine Learning Approach(2022) Topcu, Deniz Ilhan; Bayraktar, Nilufer; https://orcid.org/0000-0002-1219-6368; https://orcid.org/0000-0002-7886-3688; 000819864400001; E-3717-2019; Y-8758-2018Objectives Automated machine learning (AutoML) tools can help clinical laboratory professionals to develop machine learning models. The objective of this study was to develop a novel formula for the estimation of urine osmolality using an AutoML tool and to determine the efficiency of AutoML tools in a clinical laboratory setting. Methods Three hundred routine urinalysis samples were used for reference osmolality and urine clinical chemistry analysis. The H2O AutoML engine completed the machine learning development steps with minimum human intervention. Four feature groups were created, which include different urinalysis measurements according to the Boruta feature selection algorithm. Method comparison statistics including Spearman correlation, Passing-Bablok regression analysis were performed, and Bland Altman plots were created to compare model predictions with the reference method. The minimum allowable bias (24.17%) from biological variation data was used as the limit of agreement. Results The AutoML engine developed a total of 183 ML models. Conductivity and specific gravity had the highest variable importance. Models that include conductivity, specific gravity, and other urinalysis parameters had the highest R-2 (0.70-0.83), and 70-84% of results were within the limit of agreement. Conclusions Combining urinary conductivity with other urinalysis parameters using validated machine learning models can yield a promising surrogate. Additionally, AutoML tools facilitate the machine learning development cycle and should be considered for developing ML models in clinical laboratories.Item Serum endocan levels in fresh IVF/ICSI cycles in women with endometriosis: a comparative prospective study(2022) Ceran, Mehmet Ufuk; Yilmaz, Nafiye; Colak, Eser; Bayraktar, Nilufer; Tohma, Yusuf Aytac; Zeyneloglu, Hulusi BulentBackground: The current study tested the level of endocan, which is thought to have an effective role in both endothelial dysfunction and inflammation, in infertile women with endometriosis treated with in vitro fertilizationlintracytoplasmic sperm injection (IVF/ICSI). It is based on the hypothesis of chronic inflammation in the pathophysiology of endometriosis. Methods: This prospective case control study included a total of 64 women who were in the IVF/ICSI program. The women were divided into two groups: endometriosis (n = 32) and non-endometriosis (n = 32). Their baseline characteristics, stimulation parameters, and IVF/ICSI outcomes (clinical pregnancy and live birth rates) were recorded. Blood samples collected at the beginning of the IVE cycle for endocan levels were analyzed with a sandwich enzyme immunoassay and the results were documented. Results: The endocan levels in the endometriosis group were significantly higher than those in the non-endometriosis group, i.e., 5010 pg/mL and 2738 pg/mL, respectively (p < 0.05). A significant weakly positive correlation was found between endocan levels and the presence of endometriosis (p < 0.05, r: 0.284). The cut-off value for endometriosis was determined as 4693 pg/mL with a sensitivity of 53.13% and a specificity of 78.12%. Clinical pregnancy was insignificantly higher in the non-endometriosis group (p = 0.079). However, live birth rates were significantly higher in the non-endometriosis group (p < 0.05). No correlation was found between clinical pregnancy and live birth rate and endocan levels (p > 0.05). Conclusion: High endocan levels were detected in women who underwent IVF/ICSI treatment for endometriosis and infertility and there was a positive correlation between them. However, there was no relationship between endocan levels and IVF/ICSI outcomes.Item Severe chronic periodontitis is not common in Acromegaly: Potential protective role of gingival BMP-2(2021) Bascil, Sibel; Turhan Iyidir, Ozlem; Bayraktar, Nilufer; Ertorer, Melek Eda; Bascil Tutuncu, Neslihan; 0000-0002-0225-2477; 0000-0001-5305-6807; 0000-0002-7886-3688; 0000-0001-7357-8709; 0000-0002-1816-3903; 33421969; K-7904-2019; Y-8758-2018; ABI-3705-2020; ABG-5027-2020Background/aim : Advanced chronic periodontitis is observed rarely in acromegaly. Periodontal tissue including the alveolar bone is seemed to be spared from the systemic metabolic derangements of bone in this patient population. Chronic elevation of growth hormone, IGF-1, and bone morphogenetic proteins may play a role in periodontal tissue regeneration in acromegalics. In this study, we aimed to evaluate the potential roles of local gingival bone morphogenetic proteins (BMP) in periodontal tissue pathology in acromegaly. Materials and methods: Thirty-five patients with acromegaly and 22 healthy subjects were recruited. All the participants were examined by the same periodontologist for the diagnosis of periodontal diseases. BMP-2 and-4 were studied in gingival crevicular fluid. Results: Gingival BMP-2 and BMP-4 levels were similar in acromegaly and control groups in general, with and without chronic periodontitis. For all the participants, gingival BMP-2 levels were statistically lower in those participants with chronic periodontitis then those without periodontitis (29.4 +/- 11.2 vs. 41.2 +/- 23.2, respectively, p = 0.027). Causal relation between the gingival BMP levels and periodontal tissue health status was tested with one way ANOVA which revealed a significant difference between gingival BMP-2 levels in those with different degrees of periodontal tissue pathology (p = 0.025). When analyzed separately, gingival BMP-2 levels revealed a causal relation with the degree of periodontal pathology with borderline significance only in patients with acromegaly (p = 0.057). Conclusion: Acromegaly is a disease with an unexpectedly low frequency of advanced periodontitis, irrespective of the long disease duration and pathognomonic oral manifestations. BMP-2 might have a protective role against chronic advanced periodontitis in these patients.Item Phosphodiesterase 4 inhibitor plus metformin is superior to metformin alone for the treatment of polycystic ovary syndrome: A rat model study(2019) Tohma, Yusuf Aytac; Onalan, Gogsen; Tepeoglu, Merih; Bayraktar, Nilufer; Colak, Eser; Ozcimen, Emel Ebru; Zeyneloglu, Hulusi Bulent; 30988783The role of metformin in the management of polycystic ovary syndrome (PCOS) and PCOS-related obesity remains controversial. Recent research on the treatment of PCOS-related obesity investigated novel therapeutic agents with the potential to work synergistically with metformin. The aim of the present study was to determine the synergistic effect of a phosphodiesterase 4 inhibitor (PDE4i) and metformin on weight and hormonal changes in a rat model of PCOS. A total of 40 female Sprague-Dawley rats were randomly divided into 4 groups (n=10/group): Sham; PCOS control (no medication after PCOS induction with dehydroepiandrosterone); metformin (300 mg/kg/day p.o. after PCOS induction); and metformin + PDE4i (300 mg/kg/day p.o. metformin + 0.5 mg/kg/day p.o. PDE4i after PCOS induction). The body weight was measured every 7 days, from day 1 to day 49. Vaginal smears were performed and examined daily via light microscopy for determination of the stage of each rat's estrous cycle. At the end of 21st day and at the end of the study, blood samples were collected from rats and the testosterone and insulin levels were measured. Immunohistochemical staining was performed to quantify phosphorylated cyclic AMP response element-binding protein expression in all groups. At the end of the study, the median body weight differed significantly among the groups ((2)=30.581, P<0.001), being the highest in the PCOS control group and the lowest in the metformin + PDE4i group. At the end of the study, the median testosterone level differed significantly among the groups ((2)=27.057, P<0.001), being the highest in the PCOS control group and the lowest in the metformin + PDE4i group. The cycle was restored to normal at the end of the study in all the rats in the metformin and metformin + PDE4i groups, whereas an irregular cycle persisted in all the rats in the PCOS control group. In conclusion, PDE4i + metformin was superior to metformin alone in reducing weight gain and decreasing the testosterone levels in a rat model of PCOS.Item Amifostine enhances the antioxidant and hepatoprotective effects of UW and HTK preservation solutions(2014) Akbulut, Sami; Sevmis, Sinasi; Karayakali, Hamdi; Bayraktar, Nilufer; Unlukaplan, Muge; Oksuz, Ergun; Dagdeviren, Atilla; 25232264AIM: To investigate whether amifostine contributes to the antioxidant and cytoprotective effects of histidine-tryptophan-ketoglutarate (HTK) and University of Wisconsin (UW) preservation solutions. METHODS: Forty-eight Sprague Dawley male rats were equally divided into six groups: (1) ringer Lactate (RL) group; (2) RL + amifostine (RL + A) group; (3) HTK group; (4) HTK + A group; (5) UW group; and (6) UW + A group. Rats in the RL + A, HTK + A and UW + A groups were administered amifostine intraperitoneally at a dose of 200 mg/kg prior to laparotomy. The RL group was perfused with RL into the portal vein. The RL + A group were perfused with RL into the portal vein after amifostine administration. The HTK group received an HTK perfusion while the HTK + A group received an HTK perfusion after administration of amifostine. The UW group received a perfusion of UW, while the UW + A group received a UW perfusion after amifostine administration. Liver biopsy was performed to investigate histopathological, immunochemical [transferase mediated dUTP nick end labeling (TUNEL), inducible nitric oxide syntetase (iNOS)] and ultrastructural alterations. Biochemical alterations were determined by examining levels of alanine aminotransferase, alkaline phosphatase and nitric oxide in the perfusion fluid. RESULTS: Pathological sinusoidal dilatation and centrilobular hydropic alteration were significantly lower in the groups that received amifostine prior to preservation solution perfusion. Although the best results were obtained in the UW + A group, we did not observe a statistically significant difference between the UW + A and HTK + A groups. iNOS grades were significantly lower in the amifostine groups 12 h after treatment. When the amifostine groups were compared against each other, the iNOS grades obtained from the UW + A and HTK + A groups were similar while the RL + A group had a much poorer score. TUNEL assays demonstrated a lower apoptosis ratio in the amifostine groups than in the non-amifostine groups 12 h after treatment. No statistically significant difference was observed between the UW + A and HTK + A groups for apoptosis. Cellular ultrastructure was best preserved in the UW + A and HTK + A groups. CONCLUSION: Here, we show that preoperative administration of a single dose of amifostine is sufficient to minimize the preservation damage in hepatic cells. (C) 2014 Baishideng Publishing Group Inc. All rights reserved.Item Endothelial dysfunction and insulin resistance in young women with polycystic ovarian syndrome(2014) Yavuz Taslipinar, Mine; Kilic, Nedret; Bayraktar, Nilufer; Guler, Ismail; Gulcan Kurt, Yasemin; Goktas, Tayfun; Taner, Mehmet Zeki; Himmetoglu, Mehmet Ozdemir; Yaman, Halil; Taslipinar, Abdullah; 25539546Background/aim: To evaluate whether there is a correlation between insulin resistance and nitric oxide-related endothelial dysfunction in patients with polycystic ovarian syndrome (PCOS). Materials and methods: The study was conducted with 25 young women with PCOS and 25 young healthy women, between 18 and 35 years of age. Plasma asymmetric dimethylarginine (ADMA) levels, serum nitric oxide (NO) levels, and homeostatic model assessment of insulin resistance (HOMA-IR) rates were measured in both the patient and control groups. Results: Plasma ADMA levels were significantly higher in PCOS patients than in the controls (P = 0.001). Serum NO levels were significantly lower in patients than in the controls (P = 0.008). The HOMA-IR rates, accepted as an insulin resistance parameter, were significantly higher in patients than in the controls (P = 0.001). Conclusion: Results of the present study indicate that, independent of age, body mass index, and blood lipid profile, there is significant insulin resistance in PCOS patients. However, no correlation was found between HOMA-IR as an insulin resistance determinant and altered ADMA and NO levels. This finding may indicate that there are additional mechanisms of cardiovascular risks in PCOS patients other than insulin resistance.Item Serum Neuron-specific Enolase Levels in Preterm and Term Newborns and in Infants 1-3 Months of Age(2015) Abbasoglu, Aslihan; Sarialioglu, Faik; Yazici, Nalan; Bayraktar, Nilufer; Haberal, Aysegul; Erbay, Ayse; 25315754Background: Elevated serum levels of neuron-specific enolase (NSE) was initially assumed to be specific to neuronal tumors (particularly neuroblastoma), but is now known to accompany nontumoral conditions and tumors other than neuroblastomas. There is a need to establish normal ranges for NSE, especially in early infancy. The aims of this study were to determine reference values for NSE in newborns and young infants and to assess whether NSE levels in early infancy (i.e., preterm infants and term infants) differ from the adult reference range for this enzyme. Methods: We enrolled 140 healthy babies, which included 40 preterm newborns (3-15 days old and born at 28-42 weeks gestation), 40 term newborns (< 1 month old and born at term), and 60 young infants 1-3 months old (n = 20 per subgroup of 1-, 2-, and 3-month-old infants). The determination of NSE levels was performed by the electrochemiluminescence immunoassay (ECLIA) method using the Elecysys 2010 device (Roche Diagnostics, Mannheim, Germany). The mean serum NSE levels for the preterm newborns was 21.83 +/- 15.06 ng/mL [95% confidence interval (95%Cl), 16.95-26.71 ng/mL]; term newborns, 18.06 +/- 12.83 ng/mL (95%Cl, 13.94-22.19 ng/mL); and young infants, 9.09 +/- 4.38 ng/mL (95%Cl, 7.96 -10.23 ng/mL). The mean serum NSE level for infants 1-3 months old was within the ECLIA kit's normal range (4.7-18 ng/mL for adults), whereas the corresponding means for the preterm and term newborns were higher (p < 0.001, for both). Conclusion: Our findings suggest that adult reference values should not be applied to the pre-term and term age groups. Copyright (C) 2014, Taiwan Pediatric Association. Published by Elsevier Taiwan LLC. All rights reserved.Item Comparison of Carvedilol and Metoprolol for Preventing Contrast-Induced Nephropathy after Coronary Angiography(2015) Yilmaz, Mustafa; Aydinalp, Alp; Okyay, Kaan; Tekin, Abdullah; Bal, Ugur Abbas; Bayraktar, Nilufer; Yildirir, Aylin; Muderrisoglu, Haldun; 26195972Aims: Contrast-induced nephropathy (CIN) is one of the most common causes of hospital-acquired acute renal failure. Oxidative stress and vasoconstriction might play key roles in its pathogenesis. In a few experimental models, antioxidant properties of carvedilol have been documented. The aim of this study was to analyze and compare the effects of carvedilol and metoprolol on the development of CIN in patients undergoing coronary angiography. Methods: One hundred patients currently taking metoprolol and 100 patients currently taking carvedilol were enrolled into the study. Venous blood samples were obtained before and 48 h after contrast administration. Cystatin C and malondialdehyde values were examined and compared. CIN was defined as a creatinine increase of at least 25% or 0.5 mg/dl from the baseline value. Results: Seven patients in the carvedilol group (7%) and 22 patients in the metoprolol group (22%) developed CIN (p = 0.003). In the metoprolol group, the median cystatin C concentration increased significantly from 978 to 1,086 ng/ml (p = 0.001) 48 h after radiocontrast administration. In the carvedilol group, the median cystatin C concentration did not change significantly (1,143 vs. 1,068 ng/ml; p = 0.94). In the metoprolol group, the mean malondialdehyde concentration increased significantly from 7.09 +/- 1.48 to 8.38 +/- 2.6 nmol/l (p < 0.001). In the carvedilol group, the mean serum malondialdehyde concentration did not change significantly (7.44 +/- 1.21 vs. 7.56 +/- 1.11 nmol/l; p = 0.59). Conclusion: When compared to metoprolol, carvedilol might decrease oxidative stress and subsequent development of CIN. (C) 2015 S. Karger AG, Basel