Meltem Yardim
Fırat University
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Featured researches published by Meltem Yardim.
Biotechnic & Histochemistry | 2016
Suleyman Aydin; Tuncay Kuloglu; Mehmet Resat Ozercan; Serdal Albayrak; Unal Bakal; Musa Yilmaz; Mehmet Kalayci; Meltem Yardim; Mehmet Sarac; Ahmet Kazez; Hilal Kocdor; Burhan Hakan Kanat; Ibrahim Hanifi Ozercan; Gonen M; Bilgen M; Balgetir F
Cancer is the leading cause of morbidity and mortality worldwide. Some studies have shown that high heat kills cancer cells. Irisin is a protein involved in heat production by converting white into brown adipose tissue, but there is no information about how its expression changes in cancerous tissues. We used irisin antibody immunohistochemistry to investigate changes in irisin expression in gastrointestinal cancers compared to normal tissues. Irisin was found in human brain neuroglial cells, esophageal epithelial cells, esophageal epidermoid carcinoma, esophageal adenocarcinoma and neuroendocrine esophageal carcinoma, gastric glands, gastric adenosquamous carcinoma, gastric neuroendocrine carcinoma, gastric signet ring cell carcinoma, neutrophils in vascular tissues, intestinal glands of colon, colon adenocarcinoma, mucinous colon adenocarcinoma, hepatocytes, hepatocellular carcinoma, islets of Langerhans, exocrine pancreas, acinar cells and interlobular and interlobular ducts of normal pancreas, pancreatic ductal adenocarcinoma, and intra- and interlobular ducts of cancerous pancreatic tissue. Histoscores (area × intensity) indicated that irisin was increased significantly in gastrointestinal cancer tissues, except liver cancers. Our findings suggest that the relation of irisin to cancer warrants further investigation.
Biochemistry Insights | 2016
Unal Bakal; Suleyman Aydin; Mehmet Sarac; Tuncay Kuloglu; Mehmet Kalayci; Gokhan Artas; Meltem Yardim; Ahmet Kazez
A 112-amino-acid protein irisin (IRI) is widely expressed in many organs, but we currently do not know whether appendix tissue and blood cells express it. If appendix tissue and neutrophil cells express IRI, measuring its concentration in biological fluids might be helpful in the diagnosis of acute appendicitis (AA), since neutrophil cells are the currently gold-standard laboratory parameters for the diagnosis of AA. Therefore, the purpose of this study was to investigate the suitability of enzyme-linked immunosorbent assay-based measurements of the proposed myokine IRI for the discrimination of patients with AA from those with acute abdominal pain (AP) and healthy controls. Moreover, immunoreactivity to IRI was investigated in appendix tissues and blood cells. Samples were collected on admission (T1), 24 hours (T2), and 72 hours (T3) postoperatively from patients with suspected AA and from patients with AP corresponding to T1-T3, whereas control subject blood was once corresponding to T1. IRI was measured in serum, saliva, and urine by using enzyme-linked immunosorbent assay, whereas in appendix tissue and blood cells, IRI was detected by immunohistohcemistry. Appendix tissue and blood cells (except for erythrocytes) are new sources of IRI. Basal saliva, urine, and serum levels were higher in children with AA compared with postoperative levels (T2) that start to decline after surgery. This is in line with the finding that IRI levels are higher in children with AA when compared with those with AP or control subject levels, most likely due to a large infiltration of neutrophil cells in AA that release its IRI into body fluids. Measurement of IRI in children with AA parallels the increase or decrease in the neutrophil count. This new finding shows that the measurement of IRI and neutrophil count can together improve the diagnosis of AA, and it can distinguish it from AP. IRI can be a candidate marker for the diagnosis of AA and offers an additional parameter to neutrophil count. The promising receiving operating curve results indicate the following sensitivities and specificities, respectively, for IRI: serum 90% and 55%, saliva 90% and 60%, and urine 90% and 50%. Serum neutrophil count gave a sensitivity of 90% and a specificity of 90%. This promising result now needs to be confirmed in a larger group of patients.
Life Sciences | 2017
Mehmet Kalayci; Mehmet Ali Kocdor; Tuncay Kuloglu; Ibrahim Sahin; Mehmet Sarac; Aziz Aksoy; Meltem Yardim; Semih Dalkilic; Onur Gursu; Suna Aydin; Ramazan Fazil Akkoc; Meltem Ugras; Gokhan Artas; Ibrahim Hanifi Ozercan; Kader Ugur; Suleyman Aydin
Aims: The purpose of our investigative work has been to determine whether there can be therapeutic roles in the administration of sildenafil citrate, heparin and several neuropeptides on an animal model where gastric ulcers were induced with acetic acid, and to compare their efficacy. Materials and methods: The animals were divided into 13 groups, with 4 animals in each. Gastric ulcers was induced in the animals of 12 groups with one untreated group being left as the control (Group I ‐ control; given normal saline (NS)). The other groups were: Group II (ulcer + NS); Group III (5 mg/kg sildenafil citrate, low dose); Group IV (10 mg/kg sildenafil citrate, high dose); Group V (0.6 mg/kg heparin, low dose); Group VI (6 mg/kg heparin, high dose); Group VII (20 nmol/kg des‐acyl ghrelin); Group VIII (40 nmol/kg des‐acyl ghrelin); Group IX (4 nmol/kg acyl ghrelin); Group X (8 nmol/kg acly ghrelin); Group XI (20 pmol/kg Nesfatin‐1); Group XII (15 nmol/kg Obestatin) and Group XIII (5 nmol/kg Neuropeptide Y). Gastric neuropeptide expression was measured using an immunohistochemical method, and the amount in circulation was detected using ELISA. To compare with no treatment, the controls and other treatment groups, we recorded loss of the surface epithelium of the stomach, erosion, bleeding and inflammatory cell infiltration in the upper halves of the gastric glands. Key findings: The muscularis and the layers beneath it were, however, apparently normal. The gastric mucosa healed with little or no inflammation when sildenafil citrate, low dose heparin, ghrelin, NUCB2/Nesfatin‐1, obestatin, Neuropeptide Y were administered. Significance: Overall the data indicate that low dose heparin, and especially sildenafil citrate and neuropeptides, can be used clinically as an alternative approach in the treatment of the gastric ulcer. HIGHLIGHTSSildenafil citrate is the most promising agent in the treatment of gastric (peptic) ulcer.Neuropeptides can be important among the options for the treatment of gastric ulcers.Although heparin has the potential to treat the gastric ulcer, it is the weakest option.Nesfatin‐1, Obestatin and Neuropeptide Y decrease in the circulation and the gastric tissue when ulcers are present.
Clinical and Experimental Reproductive Medicine | 2017
Aynur Erşahin; Mustafa Acet; Suat Süphan Erşahin; Tuba Acet; Meltem Yardim; Omer Kenanoglu; Suleyman Aydin
Objective The aim of this study was to assess the changes of follicular fluid (FF) and serum levels of cerebellin precursor protein 1 (cbln1) and betatrophin in patients with polycystic ovary syndrome (PCOS) undergoing in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) with a gonadotropin-releasing hormone (GnRH) antagonist protocol. Methods Twenty infertile women with PCOS and 20 control women diagnosed as poor responders undergoing ovarian stimulation with a GnRH antagonist were included. Blood samples were obtained during ovum pick-up. Follicular fluid from a dominant follicle was collected from the subjects. Using enzyme-linked immunosorbent assays, FF and serum levels of cbln1 and betatrophin were measured in both groups of participants. Metabolic and hormonal parameters were also determined and correlated with each other. Results Both groups of women had similar serum and FF betatrophin levels (55.0±8.9 ng/mL vs. 53.1±10.3 ng/mL, p=0.11). The serum and FF betatrophin levels of poor responders were found to be similar (49.9±5.9 ng/mL vs. 48.9±10.7 ng/mL, p=0.22). Conversely, the FF cbln1 levels of PCOS women were found to be significantly higher than the serum cbln1 levels (589.1±147.6 ng/L vs. 531.7±74.3 ng/L, p<0.02). The FF cbln1 levels of control participants without PCOS were significantly higher than their serum cbln1 levels (599.3±211.5 ng/L vs. 525.3±87.0 ng/L, p=0.01). Positive correlations were detected among body mass index, insulin resistance, serum insulin, total testosterone, and betatrophin levels in the PCOS group. Conclusion Follicular fluid betatrophin and cbln1 concentrations may play a pivotal role on follicular growth in PCOS subjects undergoing IVF/ICSI with an antagonist protocol.
Cardiovascular Journal of Africa | 2017
Suna Aydin; Tuncay Kuloglu; Suleyman Aydin; Meltem Yardim; Davut Azboy; Zeki Temizturk; Ali Kemal Kalkan; Mehmet Eren
Summary Aim Insufficient oxygen supply to organs and tissues due to reduced arterial or venous blood flow results in ischaemia, during which, although ATP production stops, AMP and adenosine continue to be produced from ATP. The fate of irisin, which causes the production of heat instead of ATP during ischaemia, is unknown. Iloprost and sildenafil are two pharmaceutical agents that mediate the resumption of reperfusion (blood supply) via vasodilatation during ischaemic conditions. Our study aimed to explore the effects of iloprost and sildenafil on irisin levels in the heart, liver and kidney tissues and whether these pharmaceutical agents had any impact on serum irisin and nitric oxide levels in rats with induced experimental myocardial ischaemia. Methods The study included adult male Sprague-Dawley rats aged 10 months and weighing between 250 and 280 g. The animals were randomly allocated to eight groups, with five rats in each group. The groups were: sham (control), iloprost (ILO), sildenafil (SIL), ILO + SIL, myocardial ischaemia (MI), MI + ILO, MI + SIL and MI + ILO + SIL. The treatment protocols were implemented before inducing ischaemia, which was done by occluding the left coronary artery with a plastic ligature for 30 minutes. Following the reperfusion procedure, all rats were sacrificed after 24 hours, and their heart, liver and kidney tissues and blood samples were collected for analyses. An immunohistochemical method was used to measure the change in irisin levels, the ELISA method to quantify blood irisin levels, and Griess’ assay to determine nitric oxide (NO) levels in the serum and tissue. Myocardial ischaemia was confirmed based on the results of Masson’s trichrome staining, as well as levels of troponin and creatine kinase MB. Results Irisin levels in biological tissue and serum dropped statistically significantly in the ischaemic group (MI), but were restored with ILO and SIL administration. Individual SIL administration was more potently restorative than individual ILO administration or the combined administration of the two agents. NO level, on the other hand, showed the opposite tendency, reaching the highest level in the MI group, and falling with the use of pharmaceutical agents. Conclusions Individual or combined administration of ILO and SIL reduced myocardial ischaemia and NO levels, and increased irisin levels. Elevated levels of irisin obtained by drug administration could possibly contribute to accelerated wound recovery by local heat production. Sildenafil was more effective than iloprost in eliminating ischaemia and may be the first choice in offsetting the effects of ischaemia in the future.
Journal of Ophthalmology | 2018
Yavuz Oruc; Sinem Keser; Elif Yusufoglu; Fatih Celik; Ibrahim Sahin; Meltem Yardim; Suleyman Aydin
Purpose Pseudoexfoliation syndrome (PEX) is an eye disease that develops under the influence of regional population differences, genetic factors, age, and environmental factors and is characterized by visualization of a gray-white fibrogranular substance in the lens anterior capsule and/or pupil margin during anterior segment examination. The underlying biochemical mechanisms of the disease have not yet been fully elucidated. Therefore, this study was designed to show the changes in aqueous humor and blood serum levels of matrix metalloproteinases (decorin and tenascin C), total antioxidants (TAS), and total oxidants (TOS) in both cataract patients who have unilateral PEX material and cataract patients who do not have unilateral PEX material. Methods Biological samples were simultaneously collected from 22 cataract patients who had unilateral pseudoexfoliation (PEX patients) and 22 cataract patients who did not have unilateral pseudoexfoliation (control patients). From the collected biological samples, decorin (DEC) and tenascin C (TN-C) were measured with the enzyme-linked immunosorbent assay (ELISA) method, and TAS and TOS were measured with an autoanalyzer. Results When decorin, tenascin C, and TOS values of PEX patients were compared with those of control patients, there was a statistically significant increase in all three parameters. Conversely, TAS values showed a statistically significant decrease in PEX patients compared to controls. DEC, TN-C, TAS values, and TOS values were significantly higher in aqueous fluid than in blood in both the PEX patient and control groups. Conclusions We suggest that parameters such as DEC, TN-C, TAS, and TOS play a role in the etiopathology of pseudoexfoliation syndrome. Thus, bringing these increased levels of extracellular proteins and TOS and decreased levels of TAS back to within physiological limits can mediate the reorganization of the blood-aqueous fluid barrier and slow the progression of pseudoexfoliation syndrome.
Turkish Journal of Medical Sciences | 2017
Nevzat Gözel; Ahmet Karataş; Meltem Yardim; Mesude Seda Kinaci; Ramazan Ulu; Fatih Demircan; Faruk Kılınç; Burak Öz; Emir Dönder; Suleyman Aydin; Süleyman Serdar Koca
Background/aim: The pathogenesis of Raynauds phenomenon (RP) has not yet been fully elucidated. RP is characterized by exaggerated cold-induced vasoconstriction. Urotensin II (UII) is a potent vasoconstrictor. The aim of the present study was to evaluate plasma UII levels in both primary RP and secondary RP associated with systemic sclerosis (SSc).Materials and methods: Fifteen patients with primary RP, 30 patients with RP secondary to SSc, and 30 healthy controls (HC) were included in the study. Raynaud condition scores (RCS) were determined in the primary RP and SSc groups. Modified Rodnan skin score (MRSS) was determined for the SSc patients. Plasma UII level was analyzed by the ELISA method. Results: When compared to the HC group, plasma UII level was lower in the secondary RP group, but not in the primary RP group. Plasma UII level was not directly related to RCS in either the primary or secondary RP group. Moreover, it was not correlated with MRSS in the secondary RP group.Conclusion: The results of the present study suggest that UII is not associated with primary RP. Its level was lower in the secondary RP (SSc) patients. Therefore, it can be concluded that decreased UII level is related to SSc instead of RP.
Diagnostic Cytopathology | 2017
Adile Ferda Dagli; Nurhan Sahin; Zehra Bozdag; Ozlem Ucer; Ayse Nur Akatli; Gokhan Artas; Ibrahim Sahin; Meltem Yardim; Semih Dalkilic; Ramazan Fazil Akkoc; Sercan Simsek; Suleyman Aydin
Use of smokeless tobacco (ST) is increasing in many communities. We investigated whether ST alters the cytological and cytomorphometric features of buccal mucosa cells.
Cellular and Molecular Biology | 2017
Mehmet Sarac; Unal Bakal; Tugay Tartar; Tuncay Kuloglu; Meltem Yardim; Gokhan Artas; Suleyman Aydin; Ahmet Kazez
Testicular torsion (TT) is a common urological problem in the field of pediatric surgery. The degree and duration of torsion determines the degree of testicular damage; however, its effects on the expression of octanoylated ghrelin and nucleobindin 2 (NUCB2) /nesfatin-1 synthetized from testicular tissue remain unclear. We explored the effects of experimentally induced unilateral TT on serum and contralateral testicular tissue ghrelin and NUCB2/nesfatin-1 levels, and determined whether N-acetyl cysteine (NAS) treatment had any effects on their expression. A total of 42 Wistar Albino strain rats were divided into 7 groups: Group (G) I control, GII sham, GIII 12-hour torsion, GIV 12-hour torsion + detorsion + 100 mg/kg NAS, GV 24-hour torsion, GVI 24-hour torsion + detorsion + 100 mg/kg NAS, and GVII 100 mg/kg NAS. Octanoylated ghrelin and NUCB2/nesfatin-1 concentrations were evaluated in serum using the ELISA method and in testicular tissue with immunohistochemical methods. Immunoreactivity of octanoylated ghrelin significantly increased in GI compared to GIII, GV, and GVI (p<0.05). NUCB2/nesfatin-1 immunoreactivity increased in GV and GVIII relative to GI (p<0.05). In the 12-hour torsion group, a significant decrease in octanoylated ghrelin levels with NAS treatment was observed; however, in the 24-hour torsion group, a significant decrease was not observed. In the 12-hour torsion + NAS treatment group, a significant change was not observed in NUCB2/nesfatin-1 expression. Following 24-hour torsion, an increase in NUCB2/nesfatin-1 levels was observed, and NAS treatment did not reverse this increase. It was determined that increases in the expression of octanoylated ghrelin and NUCB2/nesfatin-1, the latter of which was a result of TT, reflect damage in this tissue. Importantly, NAS treatment could prevent this damage. Thus, there may be a clinical application for the combined use of NAS and octanoylated ghrelin in preventing TT-related infertility.
Cardiovascular Journal of Africa | 2017
Suleyman Aydin; Mehmet Eren; Musa Yilmaz; Mehmet Kalayci; Meltem Yardim; Omer Dogan Alatas; Tuncay Kuloglu; Balaban H; Cakmak T; Kobalt Ma; Ahmet Celik
Summary Aim Enzyme-positive acute coronary syndrome (EPACS) can cause injury to or death of the heart muscle owing to prolonged ischaemia. Recent research has indicated that in addition to liver and brain cells, cardiomyocytes also produce adropin. We hypothesised that adropin is released into the bloodstream during myocardial injury caused by acute coronary syndrome (ACS), so serum and saliva levels rise as the myocytes die. Therefore, it could be useful to investigate how ACS affects the timing and significance of adropin release in human subjects Methods Samples were taken over three days after admission, from 22 EPACS patients and 24 age- and gendermatched controls. The three major salivary glands (submandibular, sublingual and parotid) were immunohistochemically screened for adropin production, and serum and saliva adropin levels were measured by an enzyme-linked immunosorbent assay (ELISA). Salivary gland cells produce and secrete adropin locally. Results Serum adropin, troponin I, CK and CK-MB concentrations in the EPACS group became gradually higher than those in the control group up to six hours (p < 0.05), and troponin I continued to rise up to 12 hours after EPACS. The same relative increase in adropin level was observed in the saliva. Troponin I, CK and CK-MB levels started to decrease after 12 hours, while saliva and serum adropin levels started to decrease at six hours after EPACS. In samples taken four hours after EPACS, when the serum adropin value averaged 4.43 ng/ml, the receiver operating characteristic curve showed that the serum adropin concentration indicated EPACS with 91.7% sensitivity and 50% specificity, while when the cut-off adropin value in saliva was 4.12 ng/ml, the saliva adropin concentration indicated EPACS with 91.7% sensitivity and 57% specificity. Conclusion In addition to cardiac troponin and CK-MB assays, measurement of adropin level in saliva and serum samples is a potential marker for diagnosing EPACS.