Person: KIVANÇ, SERTAÇ ARGUN
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KIVANÇ
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SERTAÇ ARGUN
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Publication Antibiofilm effect of probiotic lactic acid bacteria against bacillus spp obtained from the ocular surface(Verduci Publisher, 2021-01-01) Akova, Berna; Kıvanç, Sertaç Argun; Kıvanç, Merih; AKOVA, BERNA; KIVANÇ, SERTAÇ ARGUN; Tıp Fakültesi; Göz Hastalıkları Ana Bilim Dalı; 0000-0003-0995-5260; ABE-3033-2020; AAH-6518-2021OBJECTIVE: Increasing emergence of antibiotic resistance has led to developing alternative methods to overcome this issue. The antibiotic resistance is mainly associated with formation of biofilms. Restoring healthy microbiota is one of these methods to fight the biofilm formation. In terms of this, the use of probiotics is a novel approach. In this study. we aimed at investigating the effect of exopolysaccharides (EPSs) of different lactic acid bacteria as probiotics on Bacillus spp isolated from the ocular surface, which is known to form biofilms.MATERIALS AND METHODS: Pathogenic microorganisms were cultivated in "Brain-Hearth infusion" (BHI) broth, and lactic acid bacteria were grown in "De Man, Rogosa. Sharpe" and M17 broth. Molecular identification of lactic acid bacteria was made according to the sequence information of the 16S rRNA gene region. Antimicrobial activity of lactic acid bacteria was determined by sandwich overlay method. The minimum inhibitory concentration values of the exopolysaccharides and antibiofilm activity were determined by microtitration method. For evaluating the effect of EPSs of probiotic bacteria on biofilm, the mean and standard deviations of optical density values were calculated.RESULTS: The most effective EPS against B. cereus was EPS from L. rhamnosus 24, followed by EPS from L. plantarum and L. acidophilus. The biofilm formation of all pathogenic bacteria that were exposed to probiotic bacteria except L. rhamnosus 621 and 622 and L. rhamnosus 3111 was lower than the biofilm formation of the control group.CONCLUSIONS: EPSs obtained from lactic acid bacteria have antibacterial and antibiofilm activity on pathogenic bacteria isolated from ocular surface. This study is one of the pioneer studies in restoring healthy microbiota on ocular surface with the anticipated forthcoming use of topical probiotics.Publication Effects of the dibenzofuran, usnic acid, on inhibition of ocular biofilm formation due to coagulase-negative staphylococci(Int Scientific Information, Inc, 2023-04-19) Kıvanç, Merih; Kivanç, Sertaç Argun; KIVANÇ, SERTAÇ ARGUN; Akova, Berna; AKOVA, BERNA; Tıp Fakültesi; Göz Hastalıkları Ana Bilim Dalı; 0000-0003-0995-5260; AAH-6518-2021; ABE-3033-2020Background: Coagulase-negative staphylococci (CoNS) are gram-positive, aerobic, commensal bacteria found on the skin and mucous membranes, including the conjunctiva. Usnic acid (UA) is a dibenzofuran derivative isolated from lichens. This study aimed to investigate the effects of usnic acid on inhibition of ocular biofilm formation due to CoNS.Material/Methods: Nine Staphylococcus epidermidis isolates, 5 Staphylococcus hominis isolates, 2 Staphylococcus saprophyticus iso-lates, and 1 Staphylococcus capitis and Staphylococcus lentus isolates were taken as test bacteria. They were inoculated into brain heart infusion broth and incubated for 24 hours at 35 degrees C and activated. Antibiotic suscep-tibility was investigated by Kirby-Bauer disc diffusion method. Biofilm production was determined using the microtiter plate method and optical densitometry was measured at 570 nm using an automated microplate reader. Anti-biofilm activity of UA was determined by microtitration method and biofilm removal percentage was calculated.Results: All tested bacteria were found as high biofilm-producer strains; they were generally resistant to methicillin, but susceptible to vancomycin. UA inhibited the biofilm formation of S. epidermidis isolates, ranging from 5.7% to 81.5%. It inhibited the biofilm formation of S. saprophyticus and S. lentus by 73.3% and 74.3%, respective-ly. There was no effect of UA on mature biofilms of S. epidermidis 17.7H, S. epidermidis 15.41, S. hominis 9.3, S. hominis 17.2H, S. saprophyticus, and S. lentus.Conclusions: It was determined that UA exerted anti-biofilm activity on some CoNS isolated from the ocular surface. Anti-biofilm activity was found to be higher even in strains that did not show antibacterial activity.Publication Evaluation of iridocorneal angle, choroidal thickness, and retinal nerve fiber layer thickness in children with a history of retinopathy of prematurity(Lippincott Williams & Wilkins, 2020-02-01) Ulusoy, Mahmut Oguz; Kal, Ali; Kivanc, Sertac Argun; KIVANÇ, SERTAÇ ARGUN; Tıp Fakültesi; Oftalmoloji Ana Bilim Dalı; AAH-6518-2021Purpose: Retinopathy of prematurity (ROP) is proliferative retinopathy affecting premature infants associated with abnormal maturation of the retinal vasculature. We sought to evaluate iridocorneal angle, choroidal thickness, and retinal nerve fiber layer thickness (RNFLT) of the children that have a history of ROP using spectral-domain optical coherence tomography. Patients and Methods: Fifty eyes of 28 children with a history of ROP and 46 eyes of 23 healthy school-aged children were included in this study. RNFLT, choroidal thickness, and iridocorneal angle parameters [trabecular iris angle, angle opening distance (AOD500), and trabecular iris space area (TISA500) 500 mu m from the scleral spur] were evaluated using spectral-domain optical coherence tomography. Student t test was used to compare the mean of the parameters. Correlations between the variables were investigated based on the Pearson or Spearman correlation coefficient. Results: Subfoveal (ROP: 253.98 +/- 42.5; control: 286.2 +/- 71.9; P=0.045), 500 mu m (ROP: 242.04 +/- 41.8; control: 276.7 +/- 45.3; P=0.003), 1000 mu m (ROP: 237 +/- 39.7; control: 270.15 +/- 55.93; P=0.007), and 1500 mu m (ROP: 224.16 +/- 37.5; control: 259.75 +/- 55.2; P=0.003) temporal choroidal thicknesses were significantly thinner in ROP history children. None of the RNFLT parameters and ganglion cell complex thickness were different between groups. Iridocorneal angle parameters were significantly lower in children with ROP history. (trabecular iris angle: ROP=31.35 +/- 3.9 degrees, control=35.4 +/- 4.5 degrees, P<0.001; TISA500: ROP=0.167 +/- 0.05 mm(2), control=0.21 +/- 0.05 mm(2), P=0.003; AOD500: ROP=480.96 +/- 160.4 mu m, control=542.95 +/- 161.2 mu m, P=0.035). Conclusions: ROP is associated with differences in the iridocorneal angle. Possible iridocorneal angle pathology should be a consideration in children with a history of ROP.Publication Evaluation of occupational closed globe eye(Derman Medical Publ, 2015-06-01) Budak, Berna Akova; Kıvanç, Sertaç Argün; KIVANÇ, SERTAÇ ARGUN; Başkaya, Kevser; Baykara, Mehmet; BAYKARA, MEHMET; Yücel, Ahmet Ali; YÜCEL, AHMET ALİ; Tıp Fakültesi; Göz Hastalıkları Ana Bilim Dalı; 0000-0003-0995-5260; 0000-0002-5555-1649; ABE-3033-2020; AAH-6518-2021; ABI-7051-2020Aim: To evaluate closed glob injuries related to occupational accidents of patients who had official occupational accident records. Material and Method: The medical records of patients with ocular injuries who referred to Department of Ophthalmology or emergency of Uludag University, School of Medicine between January 2010 and December 2013 with official occupational accident report were retrospectively reviewed. The patients with closed globe injuries following trauma were included. Age, sex, the injured eye, the cause of the trauma, whether the precautions were taken or not by the patient, the damage due to trauma were recorded. Results: According to the official records, 108 patients referred to our clinic with closed globe injury related to occupational accident. One hundred twenty eyes of 108 patients (2 females, 106 males) were evaluated. The mean age of the patients was 33 +/- 8.6 years. The most frequent cause of injury was foreign bodies on the ocular surface followed by blunt trauma. The mean age of the patients injured with foreign bodies was found to be significantly lower than the patients injured with blunt objects (p=0.039). Thirteen patients reported that they had used preventive equipment. Discussion: It is of utmost importance that the awareness of the workers should be raised and they should be educated about the use of preventive equipment to prevent the occupational eye injuries. The education of particularly the younger patients about the occupational injuries when they begin to work may decrease the rate of occupational accident related eye injuries.Publication Comparison of two different evaluation methods for biofilm formation of S. epidermidis isolated from ocular surface(Assoc Research Vision Ophthalmology Inc, 2015-06-01) Budak, Berna Akova; Kıvanç, Sertaç Argün; Yıldız, Meral; Kıvanç, Merih; Güllülü, Gülay; Budak, Berna Akova; KIVANÇ, SERTAÇ ARGUN; YILDIZ, MERAL; Uludağ Üniversitesi; 0000-0003-0995-5260; AAH-1885-2021; AAH-6518-2021; ABE-3033-2020Publication Association of birth parameters with refractive status in a sample of caucasian children aged 4-17 years(Hindawi, 2015-01-01) Akova Budak, Berna; Kıvanç, Sertaç Argün; Olcaysu, Osman Okan; AKOVA, BERNA; KIVANÇ, SERTAÇ ARGUN; Tıp Fakültesi; Göz Hastalıkları Ana Bilim Dalı; 0000-0003-0995-5260; ABE-3033-2020; AAH-6518-2021Purpose. To investigate the association of birth parameters with refractive status in different age groups of Caucasian children. Materials and Methods. This cross-sectional study included 564 eyes of 282 children aged 4 to 17 years. All children underwent complete ophthalmologic examination. The children were divided into three groups according to their refractive status (emmetropia, myopia, and hyperopia), ages (4-7, 8-9, 10-12, and 13-17), and appropriateness for gestational age, respectively. Results. The mean age of the children was 9.2 +/- 2.8 (age range 4-17 years). The mean spheric equivalent was +0.3 +/- 1.7 (range: (-10.0)(+10.0) diopters). The mean birth weight and gestational age were 2681.1 +/- 930.8 grams (750-5000 grams) and 37.2 +/- 3.7 weeks (25-42 weeks). According to multinominal logistic regression analysis, children with myopia were more likely to have higher birth weights than emmetropic children (OR: 1.0, 95% CI: 1.000-1.001, and P = 0.028). The hypermetropes were found to be significantly small for gestational age between 13 and 17 years of age. Conclusion. Birth weight and appropriateness for gestational age as birth parameters may have an impact on development of all types of refractive errors. The hypermetropic children tended to be small for gestational age.Publication Comparison of biofilm formation capacities of two clinical isolates of staphylococcus epidermidis with and without icaA and icaD genes on intraocular lenses(Galenos Yayınevi, 2017-04-01) Kıvanç, Sertaç Argun; Kıvanç, Merih; Kılıç, Volkan; Güllülü, Gülay; Özmen, Ahmet Tuncer; KIVANÇ, SERTAÇ ARGUN; ÖZMEN, AHMET TUNCER; Tıp Fakültesi; Göz Hastalıkları Ana Bilim Dalı; AAH-6518-2021; JIQ-6672-2023Objectives: To compare biofilm formations of two Staphylococcus epidermidis (S. epidermidis) isolates with known biofilm formation capacities on four different intraocular lenses (IOL) that have not been studied before.Materials and Methods: Two isolates obtained from ocular surfaces and identified in previous studies and stored at -86 degrees C in 15% glycerol in the microbiology laboratory of the Anadolu University Department of Biology were purified and used in the study. The isolates were S. epidermidis KA 15.8 (ICA+), a known biofilm producer isolate positive for icaA, icaD and bap genes, and S. epidermidis KA 14.5 (ICA-), known as a non-biofilm producer isolate negative for icaA, icaD and bap genes. The biofilm formation capacities of the 2 isolates on 4 different IOLs were compared. Two of the IOLs were acrylic (UD613 [IOL A], Turkey; SA60AT [IOL B], USA), and the other two were polymethyl methacrylate (PMMA) (B60130C [IOL C], India; B55125C [IOL D], India). Bacterial enumeration and optical density measurements were done from biofilms that formed on the IOLs. Biofilms were imaged using scanning electron microscopy.Results: Mean bacterial counts on the IOLs were 7.1 +/- 0.4 log 10 CFU/mL with the ICA+ isolate, and 6.7 +/- 0.8 log 10 CFU/mL with the ICA-isolate; there were no statistically significant differences. Biofilm formation was lower with acrylic lenses than PMMA lenses with both isolates (p= 0.009 and p= 0.013). The highest biofilm production was obtained on IOL C (PMMA) (p< 0.001) and the lowest was obtained on IOL A (hydrophilic acrylic) (p< 0.001).Conclusion: Bacterial counts after biofilm formation were lower on acrylic lenses, especially hydrophilic acrylic with hydrophobic properties. Further animal and in vivo studies are required to support the findings of this study.Publication Does corneal hysteresis correlate with endothelial cell density?(Int Scientific Literature, 2015-04-29) Akova-Budak, Berna; Kıvanç, Sertaç Argün; AKOVA, BERNA; KIVANÇ, SERTAÇ ARGUN; Tıp Fakültesi; Göz Hastalıkları Ana Bilim Dalı; 0000-0003-0995-5260; AAH-6518-2021; ABE-3033-2020Background: Our aim was to determine if there is a correlation between corneal biomechanical properties, endothelial cell count, and corneal pachymetry in healthy corneas.Material/Methods: Ninety-two eyes of all subjects underwent complete ocular examination, including intraocular pressure measurement by Goldmann applanation tonometer, objective refraction, and slit-lamp biomicroscopy. Topographic measurements and corneal pachymetry were performed using a Scheimpflug-based (Pentacam, Oculus, Germany) corneal topographer. Corneal hysteresis (CH) and corneal resistance factor (CRF) were measured with an Ocular Response Analyzer (ORA, Reichert Ophthalmic Instruments, Buffalo, NY). Endothelial cell count measurement was done using a specular microscope (CellChek, Konan, USA).Results: Right eye values of the subjects were taken for the study. The mean CH was 11.5 +/- 1.7 mmHg and the mean CRF was 11.2 +/- 1.4 mmHg. Mean intraocular pressure was 15.3 +/- 2.3 mmHg. The mean endothelial cell count was 2754 +/- 205 cells/mm(2). No correlation was found between biomechanical properties of cornea and endothelial cell count. There was a significant positive correlation between CH, CRF, and corneal thickness (p<0.001; r=0.79).Conclusions: The corneal biomechanical properties significantly correlated with corneal thickness. We found no correlation between CH and CRF with the endothelial cell density in normal subjects.Publication Post-thyroidectomy iatrogenic horner's syndrome with heterochromia(Elsevier, 2016-03-01) Ulusoy, Mahmut Oğuz; Kıvanç, Sertaç Argun; Atakan, Mehmet; Mayalı, Hüseyin; KIVANÇ, SERTAÇ ARGUN; Tıp Fakültesi; Göz Hastalıkları Ana Bilim Dalı; AAH-6518-2021Purpose: To present a case of iatrogenic Horner's syndrome seen together with the heterochromia in the post-thyroidectomy period.Methods: A 23-year-old female patient was admitted to our clinic with complaints of low vision in the eye and difference in eye color that developed over the past two years. In the left eye, myosis and minimal ptosis (similar to 1 mm) was detected, and the color of the iris was lighter than the right eye.Results: The pre-diagnosis of left iatrogenic Horner's syndrome was finalized after 0.5% topical apraclonidine test.Conclusion: Heterochromia can be observed in iatrogenic Horner's syndrome. Copyright (c) 2016, Iranian Society of Ophthalmology. Production and hosting by Elsevier B.V.Publication The biofilm formation properties of the S. epidermidis isolates obtained from conjunctiva and multi-drug resistance(Kuwait Medical Assoc, 2020-06-01) Kılıç, Volkan; Kıvanç, Merih; Kıvanç, Sertaç Argün; KIVANÇ, SERTAÇ ARGUN; Akova, Berna; AKOVA, BERNA; Tıp Fakültesi; 0000-0003-0995-5260; AAH-6518-2021; ABE-3033-2020Objective: Biofilm was shown on ocular abiotic surfaces such as contact lenses, intra-ocular lenses, glaucoma shunts and corneal sutures. The aim of this study is to compare success of Microtiter plate (MTP) and Congo Red Agar (CRA) methods in showing biofilm formation of S.epidermidis isolates that were obtained from conjunctiva regarding presence of icaA gene locus and multi-drug resistance.Design: InterventionalSetting: Department of Biology, Faculty of Science, Eskisehir Technical UniversitySubjects: S. epidermidis isolates obtained from conjunctivas of healthy patientsInterventions: MTP and CRA methods and antibiotic susceptibility tests were done and scanning electron microscopy was performed. Main outcome measures: Biofilm forming capacity, multidrug resistance states and bacterial adhesion of S. epidermidisResults: Nine isolates were found as strong biofilm producers with MTP and CRA methods. There were six icaA negative isolates, one of which was not a biofilm producer. From the icaA and icaD positive isolates, 13 were biofilm negative with MTP method and seven were biofilm negative with CRA method. Eighteen isolates were determined as resistant to three or more antibiotics. Ten of 18 isolates were strong biofilm producer with MTP and eight of 18 isolates were strong biofilm producer with CRA. Biofilm producer isolates were found to be resistant to antibiotics.Conclusion: It is noted that biofilm formation capacity of S. epidermidis isolates that were obtained from ocular surface were determined and multidrug resistance were estimated more successfully with MTP method. However, there is no method which can successfully detect biofilm formation capacity with 100% accuracy.