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Öğe A Case-Control Study on the Oxidative Status in Women with Polycystic Ovary Syndrome Treated with Clomiphene Citrate(Int Scientific Information, Inc, 2019) Yildirim, Engin; Derici, Mehmet KursatBackground: Polycystic ovary syndrome (PCOS) is associated with infertility or subfertility due to impaired ovulation. Clomiphene citrate is a first-line treatment option for the induction of ovulation in women with PCOS. The study aimed to compare markers of oxidative stress or the total oxidative status (TOS), total antioxidant status (TAS), and levels of paraoxonase-1 (PON-1) before and after day 21 of the menstrual cycle in women with PCOS treated with clomiphene citrate to induce ovulation. Material/Methods: The study included 75 women who were divided into a control group (n=25) that included healthy untreated women, untreated women with PCOS (n=24) who had spontaneous ovulation, and women with PCOS who were treated with clomiphene citrate for subfertility or infertility (n=26) (the PCOS-CC group). The study group was treated for five days with clomiphene citrate (50 mg/day). Peripheral venous blood was sampled on day 3 and day 21 of the menstrual cycle from women in all three groups, and TAS, TOS, and PON-1 levels were measured. Results: In all three groups, TAS and PON levels were significantly reduced and TOS values were significantly increased on day 21 of the menstrual cycle. Comparison of TAS, TOS, and PON-1 levels between the three study groups on day 3 and day 21 of the menstrual cycle showed no significant difference (p=0.600, p=0.223, p=0.956, respectively). Conclusions: This study showed that spontaneous ovulation occurs in association with an oxidative state in healthy women and women with PCOS, and women with PCOS following treatment with clomiphene citrate.Öğe Differential expressions and functions of phosphodiesterase enzymes in different regions of the rat heart(Elsevier Science Bv, 2019) Derici, Mehmet Kursat; Sadi, Gokhan; Cenik, Basar; Guray, Tulin; Demirel-Yilmaz, EminePhosphodiesterase enzymes (PDEs) are responsible for the adjustment of cyclic nucleotide levels. Alterations in PDE expressions in different tissues cause conflicts between functional and clinical effects of PDE inhibitors. Therefore, the aim of this study was to investigate the gene and protein expressions and the functional role of PDEs in atrium and ventricle of rat heart The expressions of PDEs were examined in cardiac intact tissues and enzymatically isolated cells. The effects of PDE1-5 inhibitors (vinpocetine, EHNA, milrinone, rolipram, sildenafil, and IBMX) on basal and isoprenaline-stimulated contractions and sinus rate were recorded in the isolated spontaneously beating right atrium and electrically stimulated left papillary muscles. The mRNA and protein levels of PDEs were significantly different in atrial and ventricular intact tissues and isolated myocytes. Atrial contractions were increased with vinpocetine while suppressed by EHNA, milrinone, rolipram, sildenafil and IBMX. Milrinone, sildenafil and IBMX increased the heart rate whereas vinpocetine caused negative chronotropy. Papillary muscle contractions have been increased only with the vinpocetine and IBMX. Both the expression and the action of PDE-1-5 show atrial and ventricular differences. Therefore, these differences should be taken into account in the experimental or therapeutic approaches of the heart.Öğe Effects of Nd: YAG laser on tumour necrosis factor-alpha, interleukin-1beta and interferon-gamma levels in teeth with apical periodontitis: A clinical study(Wiley, 2023) Baris, Sevda Durust; Turkyilmaz, Ali; Derici, Mehmet KursatThis study aimed to evaluate the levels of tumour necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1 beta) and interferon-gamma (IFN-gamma) with asymptomatic apical periodontitis (AP). A total of 60 participants were randomly divided into two groups: the conventional irrigation (control) and the Nd: YAG laser irradiation. The interstitial fluids were obtained after root canal cleaning (day 0) and 1 week later (day 7). The TNF-alpha a, IL-1 beta and IFN-gamma. levels were assayed using the enzyme-linked immunosorbent assay. The Mann-Whitney U, continuity correction chi-square, Pearson chi-square and Fisher exact tests were used. An increased level of cytokines on day 7 in the control group was observed, without statistically significant differences (p > 0.05). All cytokine levels decreased over time in the laser group. Only the IL-1 beta level showed a significant difference (p < 0.05). Nd: YAG irradiation has a positive effect on decreasing the proinflammatory cytokine level and may help to control infection in teeth with AP.Öğe Evaluation of in vitro Anticancer Activity of Vulpinic Acid and its Apoptotic Potential Using Gene Expression and Protein Analysis(Assoc Pharmaceutical Teachers India, 2018) Kilic, Nil; Derici, Mehmet Kursat; Buyuk, Ilker; Aydin, Semra Soydam; Aras, Sumer; Cansaran-Duman, DemetLichens and their secondary metabolite are still among the many unexamined natural sources in the drug industry. This study was designed to evaluate the cytotoxic effects of vulpinic acid lichen secondary metabolite and 6.25, 12.5, 25, 50, 100, 200 and 400 mu M concentrations that treat cancer cell lines (CaCo2, HepG2, Hep2C, RD Wehi) and normal cells (Vero and L929) by MTT assay. The aim of this study was to determine the apoptotic effect of vulpinic acid on a molecular level. The determination of apoptotic molecular patterns of vulpinic acid was performed on western blot and quantitative real-time PCR (qRT-PCR) analysis. In our study, transcriptome changes on both gene and protein levels showed similar results. The determination of, mRNA levels of Bax, Bcl-2 and P53 genes were showed by qRT-PCR in cancer and normal cell lines. The results of the study showed that IC50 value of vulpinic acid altered the mRNA levels of Bax, Bcl-2 and P53 genes in all examined cancer cells when compared to the untreated cells. When the mRNA levels of the examined genes were compared, it was observed that Box gene showed more expression increase in all cell lines when compared to Bcl-2 and P53 genes. This is the first evaluation of the apoptotic effect of vulpinic acid secondary metabolite on mRNA levels. The current study highlights some points regarding vulpinic acid and its use for cancer treatment.Öğe Factors Influencing Pneumococcal Vaccination-Induced Total IgG, IgG2, and IgA Levels in Vaccinated Splenectomized Patients(Ankara Microbiology Soc, 2022) Gazi, Umut; Derici, Mehmet Kursat; Karasartova, Djursun; Gureser, Ayse Semra; Sahiner, Ibrahim Tayfun; Dolapci, Mete; Taylan Ozkan, AysegulSplenectomy is closely associated with a lifetime risk of pneumococcal and other encapsulated bacterial infections. In this study, it was aimed to investigate the change of antibody levels after vaccination against Streptococcus pneumoniae according to age, gender, years after splenectomy and the possible effect of splenectomy on IgG avidity. In addition the education and awareness levels of the participants about post-splenectomy vaccination and infectious diseases were also analyzed. In the first of the three phases of this study, 32 individuals with splenectomy were enrolled. The awareness of the patients about the possible risks after splenectomy was investigated with a simple questionnaire. Routine laboratory test results were obtained and clinical examinations were performed. In the second stage, total Ig values of 29 splenectomy patients were determined. In the third phase, 14 splenectomy and 5 healthy volunteers were vaccinated according to the Vaccination Practices Advisory Committee (ACIP) guidelines. Pneumococcal-specific antibody levels and IgG avidity were detected by enzyme linked immunosorbent assay (ELISA). It was determined that 68.8% of the splenectomized patients were unaware of their vaccination status and 78.2% of them were unaware of the increased risk of infectious diseases in asplenic conditions.. According to the hospital information management system, all 31 (96.87%) patients, except one, were vaccinated with PPV23. As expected, vaccinated patients exhibited high levels of vaccine-specific antibody production with IgG, IgG2, and IgA antibody concentrations of 321 +/- 76.68 mg/l, 73.07 +/- 8.273 mg/l, and 117.8 +/- 14.94 mg/l, respectively, but unvaccinated patients had very low antibody (IgG, IgG2 and IgA antibody concentrations were 11.5 mg/l, 1.3 mg/l and 1.2 mg/l, respectively) levels. Although there was no correlation between antibody titers and gender, age groups or presence of fever history, the decrease in total IgG, IgG2 and IgA titers were strongly correlated with the time since splenectomy. Antibody titers were found to be significantly lower in splenectomized patients vaccinated more than 10 years ago. Routine laboratory results were at normal levels except for low platelet count. On the other hand, both splenectomized and healthy control subjects displayed similar IgG avidity index values (%61.8 ve %64.4% inhibition in control and splenectomized subjects, respectively) after the vaccination schedule. It was shown that post-splenectomy vaccination with PPV23 induced high levels of pneumococcus-specific antibody production that can last for more than five years. It was determined that more efforts should be made to increase the level of knowledge about pneumococcal and other overwhelming post-splenectomy infections (OPSI) as the awareness of the patients about the risks of infection after splenectomy was poor. In particular, patients with splenectomy operation more than 10 years ago should be very careful about being asplenic as they were determined to have significantly lower level of vaccine-specific antibody production. Our study was also the first to show that splenectomy does not alter IgG avidity induced by pneumococcal vaccination.Öğe Impact of medium cut-off membranes on S100A12 and soluble receptor for advanced glycation end products(Wiley, 2023) Korucu, Berfu; Yeter, Hasan; Gonen, Sevim; Derici, Mehmet Kursat; Ronco, Claudio; Derici, UlverIntroduction Of the most remarkable molecules associated with atherosclerosis and the cardiovascular outcome are S100A12 (10,379.5 Da) and soluble receptor for advanced glycation end products (sRAGE-42,803 Da) in the hemodialysis (HD) population. We designed a study investigating the effects of the medium cut-off (MCO) dialyzers focusing on S100A12 and sRAGE in HD patients compared with low-flux and high-flux dialyzers. Methods This single-site, prospective, observational study comprises age and sex-matched HD groups (low-flux, high-flux, and MCO). Blood samples were drawn at baseline (predialysis and postdialysis) and the sixth month (predialysis). Results Groups had similar demographic features and laboratory parameters. Baseline S100A12 levels of the groups were similar [34.3 (+/- 66.5), 30.9 (+/- 42.7), and 40.6 (+/- 29.6); p = 0.13]. Compared to their baseline, the sixth-month S100A12 levels were constant in low-flux and high-flux group and significantly lower in MCO group (p = 0.16, p = 0.33, and p = 0.004). Baseline sRAGE levels of the groups were similar at baseline [2.8 (+/- 0.8), 2.7 (+/- 0.6), and 2.6 (+/- 0.7); p = 0.65], and the sixth-month [2.9 (+/- 0.5), 2.4 (+/- 0.7), and 2.4 (+/- 0.8); p = 0.24]. sRAGE levels remained constant in all groups [p = 0.84, p = 0.13, and p = 0.39]. S100A12/sRAGE ratio at baseline and sixth month was constant in low-flux [22.3 (+/- 63.7) and 18.1 (+/- 24.8); p = 0.17] and high-flux groups [11.9 (+/- 15.3) and 13.1 (+/- 5.8); p = 0.26], the ratio decreased significantly in MCO group [16.5 (+/- 11.6) to 7.8 (+/- 5.5); p = 0.03]. Conclusion Our study suggests that prolonged use of MCO dialyzers is associated with better S100A12 and sRAGE levels. Long-term studies with larger samples are needed to understand the effects of a better S100A12-sRAGE profile provided by MCO dialyzers on HD patients' cardiovascular outcomes.Öğe Is it possible to prevent contrast-induced nephropathy with dexpanthenol?(Springer, 2019) Sutcuoglu, Osman; Derici, Mehmet Kursat; Pasaoglu, Ozge Tugce; Dumludag, Burak; Helvaci, Ozant; Ogut, Betul; Derici, UlverPurposeContrast-induced nephropathy (CIN) is one of the side effects of diagnostic procedures. Oxidative stress plays an important role in CIN's pathophysiology. Dexpanthenol (Dexp) is a substance with antioxidant efficacy. We investigated the likely protective effects of dexpanthenol for CIN.MethodsTwenty-four Sprague-Dawley rats were divided randomly into four groups of 6 rats; control (group 1), Dexp (group 2), CIN (group 3) and Dexp+CIN (group 4). All rats were restricted of water moderately to facilitate of nephrotoxicity. Dexp was administered into the intraperitoneally at a dose of 500mg/kg for 5days in groups 2 and 4. The same amount of saline was applied via intraperitoneally to group 1 and 3. In CIN and Dexp+CIN groups, L-NAME (10mg/kg), tenoxicam (0.5mg/kg) and sodium amidotrizoate (10ml/kg) were administered on the 4th day via the tail vein for CIN. All rats were euthanized on the 6th day and samples for biochemical and pathological evaluations were collected.ResultsWhen the Dexp+CIN group and the CIN group were compared, it was found to be provide a significant decline at the level of acute tubular injury and necrosis in kidney biopsies by dexp. Furthermore Dexp significantly reduced the serum cystatin C (Cys-C) levels, not serum creatinine. There was no statistically significant difference between the groups in total oxidant and antioxidant levels.ConclusionsDexpanthenol did not have significant effect on oxidative stress of acute kidney injury on this rat model. However, it has ameliorated serum Cys-C levels and histopathological findings of CIN.Öğe Relationship between Serum Adipocyte Fatty Acid-Binding Protein Levels and Systemic Inflammation in Hemodialysis Patients(AVES, 2020) Korucu, Berfu; Derici, Mehmet Kursat; Deger, Serpil Muge; Cokay, Abdurrahman; Helvaci, Ozant; Elbeg, Sehri; Derici, UlverObjective: Adipocyte fatty acid-binding protein (A-FABP) is expressed in adipose tissue and macrophages. It regulates cholesterol trafficking and is involved in atherosclerosis formation. A-FABP levels are associated with cardiovascular diseases (CVDs) in patients with or without chronic kidney disease. In this study, we evaluated A-FABP levels in healthy controls and hemodialysis (HD) patients and compared the results with C-reactive protein (CRP) and interleukin-6 (IL-6) levels to determine their relationship with systemic inflammation. Materials and Methods: The study comprised 23 healthy controls and 70 HD patients, excluding individuals with an active infection, malignancy, anorexia, obesity, and hypo- or hyperthyroidism. Demographic features, laboratory findings, A-FABP levels, and levels of inflammatory markers were evaluated between and within the groups. Results: Levels of A-FABP and inflammatory markers were significantly higher in HD patients. In the HD group, 20% of the patients had documented CVD. Levels of A-FABP and inflammatory markers were similar in nondiabetic and diabetic HD patients. Age was negatively correlated with A-FABP levels. Presence of diabetes was not correlated with A-FABP. Serum CRP and IL-6 levels were significantly correlated with A-FABP levels (r=0.354, p=0.003 and r=0.393, p=0.001, respectively). Conclusion: A-FABP levels are elevated in HD patients. Systemic inflammation is significantly related to A-FABP levels in both nondiabetic and diabetic HD patients and decreases with age. Findings of this study support the adverse cardiovascular effects of systemic inflammation in HD patients.Öğe Role of silymarin (Silybum marianum) in the prevention of colistin-induced acute nephrotoxicity in rats(TAYLOR & FRANCIS LTD, 2020) Dumludag, Burak; Derici, Mehmet Kursat; Sutcuoglu, Osman; Ogut, Betul; Pasaoglu, Ozge Tugce; Gonul, Ipek Isik; Derici, UlverSilymarin (Silybum marianum) has some protective effects against drug toxicity (cisplatin, acetaminophen, adriamycin, gentamicin etc.). Colistin is a strong antimicrobial, which is frequently used in the treatment of resistant gram-negative bacterial infections in recent years although it has nephrotoxic potential. This study was aimed to determine the role of silymarin against colistin-induced acute nephrotoxicity (CIN). Rats were randomly divided into four groups. The control group was treated with tap water whereas groups 2 and 3 received silymarin (orally, 100 mg/kg/day) and colistin (intraperitoneally, 750.000 IU/kg/day) for seven days, respectively. Group 4 received both 750,000 IU/kg/day colistin and 100 mg/kg/day silymarin for seven days. After euthanasia, histopathological and biochemical examinations were completed for the kidney tissue specimens and blood samples. All parameters of the control and silymarin groups were similar. Severe weight loss was seen in the groups receiving colistin (groups 3 and 4). Silymarin significantly increased glutathione peroxidase and superoxide dismutase levels when administered with colistin in group 4 only. Acute tubular injury, tubular necrosis, meduller congestion, interstitial inflammation and apoptotic indices of colistin group were significantly higher than the control group. The administration of colistin with silymarin (group 4) was able to make some improvements in tubular necrosis and significant increase in antioxidant capacity. Silymarin increased antioxidant enzyme activity only when used in combination with colistin. The effects of silymarin may become more pronounced when used at higher doses or with a longer duration of treatment and may prevent nephrotoxicity.Öğe Skin-homing T-cell responses associated with Demodex infestation and rosacea(Wiley, 2019) Gazi, Umut; Gureser, Ayse Semra; Oztekin, Aynure; Karasartova, Djursun; Kosar-Acar, Nezahat; Derici, Mehmet Kursat; Taylan-Ozkan, AysegulAims Our aim was to investigate the skin-homing T-cell immune responses triggered in patients with Demodex infestation and/or rosacea. Methods Collected whole blood samples were divided into four groups: control subjects; nonrosacea patients with Demodex infestation (Demodex group); papulopustular rosacea (PPR) patients without Demodex infestation (Rosacea group); and PPR patients with Demodex infestation (Rosacea/Demodex group). Following ex vivo activation, skin-homing CLA+CD4+ T-cell subset levels were monitored by flow cytometry. Results When compared with control subjects, among skin-homing CD4+ T-cell subsets analysed, Demodex patients had higher T(H)9 and T-reg cell levels; Rosacea subjects displayed elevated T(H)1 cell levels; and Rosacea/Demodex patients exhibited increased frequencies of T(H)9 and T(H)22 cells. In contrast to Rosacea subjects, Rosacea/Demodex group members displayed higher T(H)2 cell levels; and when compared with Demodex groups, they had higher T(H)1 and T(H)2 but lower T-reg cell levels. Demodex group members also exhibited higher T-reg but lower T(H)1 and T(H)22 levels than Rosacea/Demodex group subjects. Conclusions The skin-homing T-cell responses associated with Demodex infestation and rosacea formation seem to influence each other. The present as well as future studies could contribute to the development of effective treatment strategies for demodicosis and rosacea.Öğe The role of oxidative damage in cataract etiopathogenesis(Sage Publications Ltd, 2023) Atalay, Enes; Ogurel, Tevfik; Derici, Mehmet KursatBackground:Cataract usually occurs due to age and diabetes, but the mechanisms of cataract formation have not yet been fully elucidated. In this study, the relationship between cataract and oxidative stress was evaluated by examining the aqueous humor reflecting lens metabolism. Objective:In this study, the effect of oxidative stress on the etiopathogenesis of cataract was investigated through the total oxidant status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), and arylesterase (ARE) levels in aqueous humor samples of patients with cataract. Design:A prospective cohort study. Methods:This study was conducted on patients who were scheduled for cataract surgery between June 2020 and March 2021. The patients were divided into four groups according to their cataract density as grades 1, 2, 3, and 4. TOS, TAS, and ARE levels of aqueous humor samples were measured spectrophotometrically, and comparisons were made between groups. Results:A total of 100 eyes of 100 patients were included in this study. TAS levels were found significantly higher in the grade 2 group compared with the grade 4 group (p = 0.006). In addition, a significant negative correlation was present between cataract grade and TAS level (r = -0.237; p = 0.018). There was no significant difference between diabetic and nondiabetic patients in terms of TAS, TOS, OSI, and ARE levels. Conclusion:The aqueous humor of patients with a high degree of cataract is characterized by low antioxidant capacity. Decreased antioxidant capacity has a role in cataract formation and progression.Öğe Usnic acid causes apoptotic-like death in Leishmania major, L. infantum and L. tropica(Springer Heidelberg, 2018) Derici, Mehmet Kursat; Cansaran-Duman, Demet; Taylan-Ozkan, AysegulLeishmaniasis, a deadly parasitic infection, threatens many people worldwide. Since the high cost, toxicity, and resistance are drawbacks of current treatment options, it is necessary to find safer and more effective new antileishmanial drugs. The aim of this study was to determine the antileishmanial activity of usnic acid and its apoptotic mechanism on Leishmania spp. promastigotes. The antileishmanial activity was evaluated by MTT assay and apoptosis-related gene expression was investigated by qRT-PCR. Usnic acid was to be effective against Leishmania major, L. infantum, and L. tropica promastigotes at IC50 =10.76 mu g/ml, 13.34 mu g/ml, and 21.06 mu g/ml, respectively. We also demonstrated a novel mechanism by which usnic acid inhibited proliferation and caused apoptosis; usnic acid upregulated p53, Bax, Casp-3, and Casp-9 gene expression and downregulated the level of Bcl-2 gene expression. Accordingly, the expression level of the P53 gene increased in L. major, L. infantum and L. tropica by 14.4-, 11.8-, and 9.5-fold, respectively, and in contrast, the Bcl-2 gene expression decreased in all three leishmaniasis by 0.8-, 0.8-, and 0.7-fold, respectively. The present study, therefore, revealed that usnic acid played a critical role in the usnic acid-induced apoptotic process in Leishmania species. Usnic acid is easily accessible and an inexpensive agent, and can be considered as an alternative therapeutic agent for Leishmania infections subject to further tests in animal models.
