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Dive into the research topics where Osman Salis is active.

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Featured researches published by Osman Salis.


International Journal of Psychiatry in Clinical Practice | 2014

Effect of methylphenidate treatment on appetite and levels of leptin, ghrelin, adiponectin, and brain-derived neurotrophic factor in children and adolescents with attention deficit and hyperactivity disorder

Serkan Sahin; Murat Yuce; Hasan Alacam; Koray Karabekiroglu; Gökçe Nur Say; Osman Salis

Abstract Objectives. We aimed to explore whether the use of methylphenidate relates leptin, ghrelin, adiponectin, and brain-derived neurotrophic factor (BDNF). In addition, the relationship between methylphenidate-related weight loss in attention deficit hyperactivity disorder (ADHD) patients and these biomolecules were evaluated. Methods. Thirty ADHD patients receiving methylphenidate and 20 healthy controls were included. Leptin, ghrelin, adiponectin, and BDNF levels were measured at baseline and after two-month treatment in both groups. Results. At baseline, leptin, ghrelin, adiponectin, and BDNF levels were similar in the ADHD and control groups. The most common adverse events occurring in the ADHD group after a 2-month treatment period included loss of appetite (70%) and weight loss (66.7%). A significant difference was found in body weight, BMI, and CGI scores of the ADHD patients after the treatment. While post-treatment ghrelin and adiponectin levels were significantly higher in the ADHD group, BDNF level was significantly lower. Post-treatment decrease in leptin levels was not significant. Conclusions. Leptin and BDNF were not associated with poor appetite and/or weight loss due to methylphenidate treatment. However, ghrelin and adiponectin might be biomolecules that play a role in underlying neurobiological mechanisms of methylphenidate-related appetite or weight loss.


Cancer Biomarkers | 2014

The anticancer effects of desferrioxamine on human breast adenocarcinoma and hepatocellular carcinoma cells.

Osman Salis; Abdulkerim Bedir; Veli Kilinc; Hasan Alacam; Sedat Gulten; Ali Okuyucu

N-myc downstream-regulated gene 1 (NDRG1) is defined as metastasis suppressor and can be downregulated in many types of cancers, and reported to be an indication of tumor progression in hepatocellular carcinomas. Several in-vivo and in-vitro studies have demonstrated that iron chelators such as Desferrioxamine (DFO) and 1-10 Phenanthroline (PHEN) are effective antitumor agents. It is suggested that these chelators deliver their antitumor activity by acting on the NDRG1 gene expression. It remains unclear why NDRG1 gene expression affects the tumors differently, or becomes affected differently. We consider that this different effect might be caused by variants. Based on this information, we developed specific primers and probes for NDRG1 mRNA variants using bioinformatics analysis, and investigated how DFO and PHEN affected the dynamics of NDRG1 variant on the cell lines of Human Breast Adenocarcinoma (MCF-7) and Hepatocellular Carcinoma (HepG2) that demonstrate opposite action for the relationship NDRG1-metastasis. We administrated various doses of DFO and PHEN into the cells to monitor cell vitality and proliferation with Real time Cell Analyzer. We analyzed the gene expression levels of study groups with Quantitative RT-PCR as well as relative gene expression. Variants of NDRG1 mRNA were transcriptionally regulated after HepG2 and MCF-7 cells were treated by iron chelators, resulting in domination of NDRG1 mRNA Variant 1 (V1) in the HepG2 calls and domination of NDRG1 mRNA Variant 2 (V2) in the MCF-7 cells. Anti-proliferative and cytotoxic effects were observed in the MCF-7 cells whereas an increased proliferation was present in the HepG2 cells.


Journal of Thoracic Disease | 2013

Effects of leflunomide on inflamation and fibrosis in bleomycine induced pulmonary fibrosis in wistar albino rats

Servet Kayhan; Aygül Güzel; Latif Duran; Serife Tutuncu; Ahmet Güzel; Mithat Günaydin; Osman Salis; Ali Okuyucu; Mustafa Yasin Selçuk

PURPOSES Pulmonary fibrosis is a rare and progressive lung disease with a high mortality rate. The treatment regimens still fail to recover the disease. Leflunomide (LEF) is an immunomodulatory agent with antiproliferative activity that is used for the treatment of rheumatoid arthritis. The purpose of the study is to investigate the potential therapeutic efficacy of LEF in bleomycin (BLM) induced pulmonary fibrosis. METHODS A total of 21 male, adult wistar albino rats were used. The animals were divided into three groups as control, BLM and BLM plus LEF groups (n=7). In BLM group, mice were treated with intratracheal instillation of BLM (2.5 U/kg). Control group received the same volume of saline instead of BLM. In LEF group, in addition to BLM, LEF (10 mg/kg, daily) was administrated by oral gavage. The effect of LEF on pulmonary inflammation and fibrosis was studied by measurements of serum clara cell protein-16 (CC-16), thiobarbituric acid reactive substance levels (TBARS), superoxide dismutase (SOD) and advanced oxidation protein products (AOPP) levels and lung tissue contents of IL-6, TNF-α and NF-κB by immunhistochemical examinations. RESULTS LEF significantly increased the level of CC-16 and decreased the level of AOPP (P=0.042 and P=0.003 respectively). Lung tissue contents of IL-6, TNF-α and NF-κB significantly decreased in LEF group compared to BLM group by immunhistochemical examinations (P<0.001). CONCLUSIONS LEF reduces oxidative stress factors, alveolar inflammation and attenuates lung injury and fibrosis.


Hypertension in Pregnancy | 2014

Increased serum heme oxygenase-1 levels as a diagnostic marker of oxidative stress in preeclampsia

Haci Kemal Erdemli; Pınar Yıldırımlar; Tayfun Alper; Ramazan Kocabaş; Osman Salis; Abdulkerim Bedir

Objective: To evaluate the utility of serum biomarkers in the diagnosis of preeclampsia (PE) and also investigate possible correlation with pathogenesis of PE. Methods: Maternal serum concentrations of heme oxygenase-1 (HO1) and N-myc downstream-regulated gene 1 (NDRG1) were measured at 27–34 weeks of gestation in a case–control study of 33 pregnant women diagnosed with PE and in 43 normotensive pregnant women without proteinuria. The Mann–Whitney U test and Spearmans correlation were used for statistical analysis. Results: The median serum HO1 level was found to be significantly higher in the PE group [76.7 ng/ml (23.4–445.7)] than control group [55.9 ng/ml (3.7–354.3)] (p = 0.006). Positive correlation was found between HO1 levels with presence of PE (r = 0.316, p = 0.005). There was no significant difference in NDRG1 values between the two groups (p = 0.226). Conclusions: Serum HO1 levels were found to be increased in patients with PE compared with normotensive pregnant women.


Cancer Biotherapy and Radiopharmaceuticals | 2012

Ouabain Targets the Unfolded Protein Response for Selective Killing of HepG2 Cells During Glucose Deprivation

Tulay Ozdemir; Rukiye Nar; Veli Kilinc; Hasan Alacam; Osman Salis; Aynur Düzgün; Sedat Gulten; Abdulkerim Bedir

Ouabain is a cardiotonic steroid and specific inhibitor of the Na(+)/K(+)-ATPase. The relationship between ouabain treatment and the unfolded protein response (UPR) in cells is not precisely understood. Therefore, we studied the possible effects of ouabain on proliferation, apoptosis, and the UPR. HepG2 cells were cultured overnight and then treated with various concentrations of ouabain (0.75 to 750 nM) in the absence or presence of 10 mM 2-deoxyglucose (2-DG) for 48 hours. We also used real-time polymerase chain reaction to obtain quantitative measurements of expression levels of Grp78, Grp94, CHOP, MTJ-1, HKII, MDR-1, MRP-1, HO-1, and Par-4. Cell number, viability, and proliferation of HepG2 cells were monitored with a real-time cell analyzer system (xCELLigence). We show that ouabain modulates the UPR transcription program and induces cell death in glucose-deprived tumor cells. Ouabain at all concentrations showed no cytotoxicity whereas all concentrations were very effective under 2-DG stress conditions. Our findings show that disruption of the UPR during glucose deprivation could be an attractive approach for selective cancer cell killing and could provide a chemical basis for developing UPR-targeting drugs against solid tumors. Ouabain use as an adjunct to conventional cancer therapy also warrants vigorous investigation.


Tumor Biology | 2016

Antimetastatic effect of fluvastatin on breast and hepatocellular carcinoma cells in relation to SGK1 and NDRG1 genes

Osman Salis; Ali Okuyucu; Abdulkerim Bedir; Ufuk Gör; Canan Kulcu; Eser Yenen; Nermin Kılıç

Metastasis occurs due to migration of the cells from primary tumor toward other tissues by gaining invasive properties. Since metastatic invasion shows a strong resistance against conventional cancer treatments, the studies on this issue have been focused. Within this context, inhibition of migration and determination of the relationships at the gene level will contribute to treatment of metastatic cancer cases. We have aimed to demonstrate the impact of TGF-β1 and fluvastatin on human breast cancer (MCF-7) and human hepatocellular carcinoma (Hep3B) cell cultures via Real-Time Cell Analyzer (RTCA) and to test the expression levels of some genes (NDRG1, SGK1, TWIST1, AMPKA2) and to compare their gene expression levels according to RTCA results. Both of cell series were applied TGF-β1 and combinations of TGF-β1/fluvastatin. Primer and probes were synthesized using Universal Probe Library (UPL, Roche) software, and expression levels of genes were tested via qPCR using the device LightCycler 480 II (Roche). Consequently, fluvastatin dose-dependently inhibited migration induced by TGF-β1 in both groups. This inhibition was accompanied by low level of SGK1 messenger RNA (mRNA) and high levels of NDRG1 and AMPKA2 mRNA. Thus, we conclude that fluvastatin plays an important role in reducing resistance to chemotherapeutics and preventing metastasis.


Cancer Biotherapy and Radiopharmaceuticals | 2014

Cytotoxic effect of fluvastatin on MCF-7 cells possibly through a reduction of the mRNA expression levels of SGK1 and CAV1.

Osman Salis; Abdulkerim Bedir; Sedat Gulten; Ali Okuyucu; Canan Kulcu; Hasan Alacam

Fluvastatin (FLU) prevents the conversion of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) to mevalonic acid by inhibiting HMG-CoA reductase and decreases cholesterol level. Although the effects of FLU treatment on several cancer types through many mechanisms have been identified, its relationship with unfolded protein response and apoptosis has not been clearly understood. In this recent study, we aimed to investigate the cytotoxic effect of Fluvastatin on MCF-7 cells and define the transcriptional regulation of specific genes during the occurrence of this cytotoxic effect. We administered 0.62, 2.5, 5, and 40 μM FLU on MCF-7 cells singly and in combination with 2-deoxyglucose (2-DG), and we monitored cell viability and proliferation for 48 hours using real-time cell analyzer system (xCELLigence). At the same time, we measured the mRNA expression levels of glucose-regulated protein 78 (GRP78), CCAAT/enhancer binding protein, homologous protein (CHOP), caveolin-1 (CAV1), NDRG1 Variant 1 and Variant 2, HMOX1, SGK1, and prostate apoptosis response-4 (PAR4) genes using quantitative real-time polymerase chain reaction (LightCycler 480 II). We accepted GAPDH gene and control groups as the reference gene and calibrator, respectively. We performed relative gene expression analyses of the study groups using the QIAGEN 2009 Relative Expression Software Tool (REST). FLU revealed an antiproliferative and cytotoxic effect on MCF-7 cells, while causing the transcriptional regulation of many genes. Of these genes, the mRNA expressions of CHOP, heme oxygenase 1 (HMOX1), N-myc downstream-regulated gene 1 (NDRG1) V1, and NDRG1 V2 increased. On the other hand, the mRNA expression levels of SGK1 and CAV1 decreased. The antiproliferative effects of FLU may be related to the decreased expression levels of SGK1 and CAV1.


Renal Failure | 2016

Is there any role of epithelial to mesenchymal transition in the pathogenesis of contrast nephropathy

Hayriye Sayarlioglu; Ali Okuyucu; Abdulkerim Bedir; Osman Salis; Eser Yenen; Garip Bekfilavioglu; Coskun Kaya

Abstract Aim: Contrast medium-induced nephropathy is one of the major complications of intravenous contrast medium use. But its pathogenesis is unclear. Epithelial mesenchymal transition (EMT) is defined as the transformation of the primer epithelial cells to mesenchymal cells. EMT in tubular cells might cause tubulointerstitial damage. In this study, we investigated whether or not EMT has a role in radiocontrast-induced nephropathy. Radiocontrast medium might be triggering reversible EMT via serum and glucocorticoid-regulated kinase 1 (SGK 1). We investigated the effect of different concentrations of the contrast agent iopromide on human proximal tubule cell (HK-2) culture by measuring the level of SGK1, snail family zinc finger 1 (SNAIL1), connective tissue growth factor (CTGF), and collagen type I alpha 1 (COL1A1). Methods: We conducted a scratch assay and qPCR. HK-2 cells were cultured in the petri dishes/flasks and starved with serum-free medium. The 40, 20, and 10 mg/mL doses of iopromide were administrated to cells. The scratches were photographed immediately and again at the 20th hour. The levels of gene expression of SGK1, SNAIL1, CTGF, and COL1A1 were measured using the real-time qPCR system at the end of the 24th hour. Results: Iopromide caused the breaking of intercellular connections, the disappearance of the cobblestone appearance of cells, and the migration of cells at the 20th hour in the scratch assay. It also increased the expression of SGK1, SNAIL1, CTGF, and COL1A1 genes. Conclusion: Our study concluded that certain important markers of EMT increase in different concentrations of the contrast agent. High osmolality might trigger EMT. The relationship between contrast agent and EMT has not been defined before. Further in vivo and in vitro studies are required.


Journal of Maternal-fetal & Neonatal Medicine | 2017

Clinical significance of glucocorticoid receptor expression in premature infants with respiratory distress syndrome.

Fevzi Ataseven; Osman Salis; Canan Aygun; Abdulkerim Bedir; Sukru Kucukoduk

Abstract Objective: Previous studies have shown the relationship between lung development and glucocorticoids, but no studies have been conducted to investigate if a relationship exists between respiratory distress syndrome (RDS) and glucocorticoid receptor (GR) expression in preterm babies. We intended to investigate whether low GR expression is a risk factor for RDS. Methods: Forty-one preterm babies, 24–35 weeks of gestation, were included in the study following informed consent from the parents. The relative gene expression of GRalpha and GRbeta was measured in the peripheral mononuclear cells form cord blood samples. The demographic characteristics of the babies and the diagnosis of RDS were recorded. Results: RDS was more frequent in the group with low GRalpha expression: 12 (60%) in the GRalpha-I group and 6 (28%) in the GRalpha-II group (p = 0.043). Oxygen use with a hood, time to reach full enteral feeds and the duration of neonatal intensive care unit stay was shorter, and nosocomial sepsis episodes and number of erythrocyte transfusions were less in the GRbeta-I group. Higher hospital costs were found in the GRbeta-II group. Conclusions: Less RDS development, and better clinical follow-up was observed in premature babies with higher GR expression.


Journal of Pediatric Surgery | 2012

The effect of curcumin on lung injuries in a rat model induced by aspirating gastrointestinal decontamination agents

Mithat Günaydin; Aygül Güzel; Ahmet Guzel; Hasan Alacam; Osman Salis; Naci Murat; Ayhan Gacar; Tolga Guvenc

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Ali Okuyucu

Ondokuz Mayıs University

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Sedat Gulten

Ondokuz Mayıs University

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Veli Kilinc

Ondokuz Mayıs University

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Aygül Güzel

Ondokuz Mayıs University

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Eser Yenen

Ondokuz Mayıs University

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Ayhan Gacar

Ondokuz Mayıs University

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Canan Kulcu

Ondokuz Mayıs University

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