Person: SOYOĞUL GÜRER, ÜMRAN
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SOYOĞUL GÜRER
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Publication Open Access Effect of antibiotics on polymorphonuclear leukocyte functions and myeloperoxidase activity, glutathione and malondialdehyde levels in allergic asthma(2015-03-31) RAYAMAN, ERKAN; Rayaman, Pervi̇N; Rayaman, Erkan; Çevi̇Kbaş, Adi̇Le; Demi̇Rtunç, Refi̇K; Özer Şehi̇Rli̇, Ahmet; Alagöz, Şeyda Gül; Gürer, Ümran SoyoğulWe investigated the effect of ciprofloxacin, rifampicine and doxycycline on myeloperoxidase (MPO) activity, glutathione (GSH) and malondialdehyde (MDA) levels in allergic asthma patients and healthy volunteers. Polymorphonuclear leukocytes (PMNs) were isolated with ficoll-hypaque gradient centrifugation method. MPO activity was assayed with modified o-dianisidine, GSH by Ellman's and MDA levels by Beuge's method. PMN functions and MDA levels of patients significantly decreased when compared with healthy volunteers. Ciprofloxacin significantly increased PMN functions, MPO activity and MDA levels of both groups. We have demonstrated that ciprofloxacin has beneficial effects on MPO activity and PMN functions in allergic asthma patients and healthy volunteers.Publication Open Access Publication Metadata only In vitro effect of amikacin, imipenem, cefodizime, IFN alpha-2a alone and combinations of antibiotics with IFN alpha-2a on polymorphonuclear leukocyte function in chronic hepatitis patients(KARGER, 2001) SOYOĞUL GÜRER, ÜMRAN; Adalati, R; Gurer, US; Cevikbas, A; Johansson, CThe in vitro effect of amikacin (8 mug/ml), imipenem (30 mug/ml), cefodizime (10 mug/ml), interferon alpha -2a (IFN alpha -2a) (10 IU/ml) and antibiotic combinations with IFNa-2a on polymorphonuclear leukocyte (PMN) functions (phagocytosis and intracellular killing of Candida albicans blastospores) was investigated in chronic hepatitis B patients. Phagocytosis and candidacidal activity was not affected after pretreatment of PMNs with amikacin and imipenem (p > 0.05). Phagocytic activity was enhanced after pretreatment of PMNs with cefodizime and IFN alpha -2a compared with that of control PMNs (p < 0.05), but candidacidal activity was not affected by the same drugs (p > 0.05). Phagocytic and intracellular activity of PMNs were not affected by combinations of IFN alpha -2a and antibiotics (p > 0.05). Copyright (C) 2001 S. Ka rger AG, Baser.Publication Metadata only Synergy between Pelargonium endlicherianum essential oil and conventional antibiotics againstNeisseria meningitidis and Haemophilus influenzae(ELSEVIER, 2022) DAMAR ÇELİK, DAMLA; Dumlupinar, Berrak; Celik, Damla Damar; Karatoprak, Gokce Seker; Gueur, Umran SoyogulThis study investigated the bactericidal effects of the essential oil of Pelargonium endlicherianum in combina-tion with four antibiotics commonly used in the treatment of bacterial meningitis (penicillin, ampicillin, cip-rofloxacin, and gentamicin) against the meningitis causative pathogens Neisseria meningitidis and Haemophilus influenzae. The phagocytic effects of these combinations were also tested against human leuko-cyte cells. The bactericidal effect of P. endlicherianum essential oil (PEO) and antibiotic combinations was dynamically detected by time-kill assay. The function of PEO and antibiotic in permeating outer membrane barriers, when used singly or in combination, was analyzed by UV spectrophotometer. The interactions between antibiotic and essential oil were calculated according to the fractional inhibitory concentration (FIC) index. While a synergistic effect of the ciprofloxacin + PEO combination was determined on N. meningitidis (FIC< 0.5), an additive effect was observed on H. influenzae (FIC= 1). Combined use of PEO with gentamicin showed a synergistic effect against N. meningitidis and H. influenzae (FIC < 0.5). The antimi-crobial effect of the penicillin + PEO combination was higher than that of penicillin + PEO used alone. The ampicillin + PEO combination had a synergistic effect on N. meningitidis and an additive effect on H. influen-zae. The results of our study showed that the essential oil increases membrane permeability activity and also has phagocytic activity in human leukocyte cells. Combining antibiotics with essential oils that target resis-tant bacteria may open up new options in combating microbial resistance. (c) 2021 SAAB. Published by Elsevier B.V. All rights reserved.Publication Metadata only Effect of fluconazole on human polymorphonuclear leucocyte functions ex vivo against Candida albicans(KARGER, 1999) SOYOĞUL GÜRER, ÜMRAN; Gurer, US; Cevikbas, A; Johansson, C; Derici, K; Yardimci, TPolymorphonuclear leucocytes (PMNs) are important components of host defence against fungi. We investigated the ex vivo effect of fluconazole on chemotaxis, adherence, superoxide anion (O-2(-)) generation and intracellular killing of Candida albicans blastoconidia after the administration of fluconazole (300 mg per os) to healthy volunteers. With regard to chemotaxis in response to zymosan-activated serum (ZAS), as measured using an agarose gel technique, fluconazole neither increased, nor decreased the chemotaxis of PMNs. The adherence was significantly enhanced after exposure of PMNs to fluconazole under ex vivo conditions, whereas, O-2(-) production after stimulation of PMNs with ZAS was not affected by fluconazole. The effect of fluconazole on intracellular killing of C. albicans blastoconidia by PMNs was determined by viable colony count, after release of yeast cells from disturbed neutrophils. Fluconazole under in vitro conditions, at a therapeutic concentration, significantly increased the intracellular killing of C. albicans by PMNs at 30 min when compared with the results obtained in ex vivo experiments (p < 0.001). During 90 min of exposure, no significant difference was found between in vitro and ex vivo conditions (p > 0.05).Publication Metadata only Colonic delivery of compression coated nisin tablets using pectin/HPMC polymer mixture(ELSEVIER, 2007) GÜRBÜZ, BURÇAK; Ugurlu, Timucin; Turkoglu, Murat; Gurer, Umran Soyogul; Akarsu, Burcak GurbuzNisin containing pectin/HPMC compression coated tablets were prepared and their in vitro behavior tested for colonic delivery. Nisin is a 34-amino-acid residue long, heat stable peptide belonging to the group A lantibiotics with wide antimicrobial activity against Grampositive bacteria. The invention can be useful for treating colonic infectious diseases such as by Clostridium difficile, and also by colonization of vancomycin-resistant enterococci. In this study, each 100 mg core tablet of nisin was compression coated with 100% pectin, 90% pectin-10% HPMC, 85% pectin-15% HPMC, 80% pectin-20% HPMC 75% pectin-25% HPMC, 100% HPMC at a coat weight of 400 mg. The concentration and the activity of nisin were quantified using Well Diffusion Agar Assay. Drug release studies were carried out in pH 3.3 buffer solution. System degradation/erosion experiments were carried out in pH 1.2, 3.3, and 6.8 buffers using a pectinolytic enzyme. The biological activity and NMR studies were performed to assess the stability of nisin during the processing and after the in vitro tests. It was found that pectin alone was not sufficient to protect the nisin containing core tablets. At the end of the 6 h 40% degradation was observed for 100% pectin tablets. HPMC addition required to control the solubility of pectin, a 5% increase in HPMC ratio in pectin/HPMC mixture provided a 2-h lag time for nisin release. Eighty percent pectin-20% HPMC appeared to be an optimum combination for further evaluation. Tablets maintained their integrity during the 6-h dissolution test, approximating the colon arrival times. Nisin was found to be active/stable during processing and after in vitro tests. Effect of polymer hydration on pectin degradation was found to be crucial for the enzyme activity. Sufficiently hydrated pectin degraded faster. The pectin/HPMC envelope was found to be a good delivery system for nisin to be delivered to the colon. (c) 2007 Elsevier B.V. All rights reserved.Publication Metadata only Effect of antituberculous drugs on human polymorphonuclear leukocyte functions in vitro(ELSEVIER SCIENCE BV, 2005) OKUYAN, BETÜL; Okuyan, B; Izzettin, FV; Sancar, M; Ertas, O; Cevikbas, A; Gurer, USThe aim of the study was to investigate antituberculous drugs effects on polymorphonuclear leukocyte (PMN) functions (phagocytic activity and intracellular killing activity) in vitro. PMNs obtained from healthy volunteers were incubated with antituberculous drugs (isoniazid [INH], rifampin [RIF], pyrazinamide [PZA], ethambutol [EMB], streptomycin [S], amikacin [A], ofloxacin [OFLX], prothionamide [PTH] and cycloserine [CyC]) and different combinations at therapeutic serum concentrations. Phagocytic activity of PMNs was significantly increased when compared with controls by PTH (p<0.001), A (p<0.001), OFLX (p<0.001), INH+RIF+S combination (p<0.01), A+OFLX combination (p<0.05), A+OFLX+CyC combination (p<0.01) and A+OFLX+CyC+PTH+EMB combination (p<0.01). Intracellular killing activity of PMNs was significantly increased by OFLX when compared with the control (p<0.05). No significant difference was observed in functions of PMN for other drugs when compared with control (p>0.05). Functions of PMN were significantly increased by OFLX when compared with A+OFLX combination (p<0.05). Phagocytic activity of PMNs was significantly increased by A+OFLX+CyC combination and A+OFLX+CyC+PTH+EMB combination when compared with A+OFLX+CyC+PTH combination and A+OFLX+CyC+PTH+PZA combination (p<0.05). No significant difference was found in functions of PMN between the other groups (p>0.05). In conclusion, some antituberculous drugs alone or in combination enhanced PMN functions, although in combination no additive or synergistic effects were detected. Moreover, none of the antituberculous drugs alone or in combination significantly decreased PMN functions. The drugs having adverse effects on immune functions would better be replaced with equally effective drugs or drug combinations having positive effects on PMN functions. (C) 2005 Published by Elsevier B.V.Publication Open Access Potential Adjuvant Effects of Nigella sativa Seeds to Improve Specific Immunotherapy in Allergic Rhinitis Patients(KARGER, 2010) GÜRBÜZ, BURÇAK; Isik, Huelya; Cevikbas, Adile; Gurer, Umran Soyogul; Kiran, Bayram; Uresin, Yagiz; Rayaman, Pervin; Rayaman, Erkan; Gurbuz, Burcak; Buyukozturk, SunaObjective: To investigate the effects of Nigella sativa seed supplementation on symptom levels, polymorphonuclear leukocyte (PMN) functions, lymphocyte subsets and hematological parameters of allergic rhinitis. Subjects and Methods: Twenty-four patients randomly selected from an experimental group of 31 (mean age 34 years) sensitive to house dust mites with allergic rhinitis and a control group of 8 healthy volunteers (mean age 23 years) were treated with allergen-specific immunotherapy in conventional doses for 30 days. After a month of immunotherapy, 12 of the 24 patients and the 8 healthy volunteers were given N. sativa seed supplementation (2 g/day orally) for 30 days. The remaining 12 patients continued only on immunotherapy during the same period. The other 7 patients were given 0.1 ml saline solution subcutaneously once a week as a placebo. The symptom scores, PMN functions, lymphocyte subsets and other hematological parameters were evaluated before and after all treatment periods. Results: There was a statistically significant increase in the phagocytic and intracellular killing tivities of PMNs of patients receiving specific immunotherapy, especially after the addition of N. sativa seed. The CD8 counts of patients receiving specific immunotherapy plus N. sativa seed supplementation significantly increased compared to patients receiving only specific immunotherapy. PMN functions of healthy volunteers significantly increased after N. sativa seed supplementation compared to baseline. Conclusion: N. sativa seed supplementation during specific immunotherapy of allergic rhinitis may be considered a potential adjuvant therapy. Copyright (C) 2010 S. Karger AG, BaselPublication Metadata only FLAVONOIDS AND BIOLOGICAL ACTIVITIES OF Centaurea stenolepis(SPRINGER, 2014) ŞEN, ALİ; Sen, Ali; Gurbuz, Burcak; Gurer, Umran Soyogul; Bulut, Gizem; Bitis, LeylaPublication Metadata only The effects of some antibiotics on polymorphonuclear leukocyte functions of elderly patients in vitro before and after zinc supplementation(ELSEVIER, 2006) SOYOĞUL GÜRER, ÜMRAN; Gurer, US; Gocer, P; Ercag, E; Erten, N; Rayaman, E; Gurbuz, B; Uzer, A; Karan, A; Cevikbas, AThe effects of ciprofloxacin, cefodizime, rifampicine, doxycycline and cefodizime+rifampicine combination on polymorphonuclear leukocyte (PMN) functions (phagocytosis and intracellular killing activity) were investigated in vitro in elderly patients and compared with those of healthy young volunteers before and after zinc supplementation. PMNs of 13 elderly hypertensive patients and 10 healthy young volunteers were isolated by Ficoll-Hypaque gradient centrifugation method from venous blood with EDTA. The subjects were given 22 mg/daily/oral zinc supplementation for I month. Serum zinc levels before and after supplementation were measured by flame atomic absorbtion spectrophotometer and the effects of each drug on PMN functions at therapeutic concentrations were investigated. Ciprofloxacin significantly increased the PMN's phagocytic activity of elderly patients (p=0.002) before zinc supplementation and significantly increased both PMN functions of elderly patients (p=0.002) after zinc supplementation. The same antibiotic significantly increased both PMN functions of healthy young volunteers (p = 0.005 and p < 0.05, respectively) before and after zinc supplementation when compared with the control (drug-free). Cefodizime significantly increased the PMN's phagocytic activity of elderly patients (p=0.003, p=0.002) before and after zinc supplementation when compared with the control (drug-free). It also significantly increased both PMN functions of healthy young volunteers (p=0.005 and p < 0.05, respectively) before and after zinc supplementation when compared with the control (drug-free). Doxycycline significantly increased PMN's intracellular killing activity of healthy young volunteers before zinc supplementation (p < 0.05) when compared with the control (drug-free) values. Rifampicine significantly decreased PMN's phagocytic activity of elderly patients (p < 0.05) after zinc supplementation. Cefodizime+rifampicine combination significantly increased PMN's phagocytic activity at therapeutic concentrations of healthy young volunteers (p=0.005) before zinc supplementation and PMN's phagocytic activity of elderly patients (p < 0.05) after zinc supplementation when compared with the control (drug-free). Consequently, in the present study from the antibiotics ciprofloxacin, cefodizime and cefodizime+rifampicine combination, which are accepted as biological response modifiers have demonstrated stimulatory effects by significantly increasing polymorphonuclear leucocyte functions (phagocytosis and/or intracellular killing activity) of elderly patients and healthy young volunteers in vitro before and safter zinc supplementation. Additionally zinc supplementation has more immunostimulatory effects on PM functions of healthy young volunteers than elderly patients. (c) 2005 Published by Elsevier B.V.