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Öğe An alternative application to tune the center frequency of a microstrip balun bandpass filter(Institute of Electrical and Electronics Engineers Inc., 2019) Ozdemir, Pinar Ozturk; Ozturk, Ali; Gorur, Ali Kursad; Karpuz, Ceyhun; Gorur, AdnanIn this paper, a novel microstrip balun bandpass filter with tunable center frequency is presented. The proposed structure is constructed by open loop resonators having varactor diodes. The varactor diodes are used to tune the resonant frequency of the resonators. By virtue of coupled open loop resonators with varactor diodes, two bandpass filters in different filtering characteristics are designed at same center frequencies. Those filters can also operate in a range of 1.8-2.2 GHz depending on the changes in the capacitances of varactor diodes. The proposed balun bandpass filter is carried out using the presented filters. For demonstration, the proposed circuit was fabricated and tested. Experimental results exhibit an acceptable agreement with the estimated results. © 2019 EuMCE.Öğe ANALYSIS OF INTERLEUKIN-17, INTERLEUKIN-23, NEOPTERIN AND NESFATIN-1 LEVELS IN THE SERA OF HASHIMOTO PATIENTS(Soc Medical Biochemists Serbia, 2023) Bayraktar, Nihayet; Eren, Mehmet Ali; Bayraktar, Mustafa; Ozturk, Ali; Erdogdu, HamzaBackground: Hashimoto's thyroiditis (HT) is an autoimmu-ne disorder affecting the thyroid gland and may present as goiter or atrophic thyroiditis that may result in various metabolic and inflammatory disorders. The aim of this study is to determine the changes in serum levels of inter-leukin-17 (IL-17), IL-23, neopterin, and nesfatin-1 para-meters in HT patients and to evaluate the possible relati-onship among these parameters.Methods: 90 HT patients and 30 healthy individuals were included in this study. Demographic data of the patients included in the study were recorded and detailed physical examinations were performed. IL-17, IL-23, neopterin, and nesfatin-1 levels were measured in the serum samples of the participants by the ELISA method.Results: Serum IL-17, IL-23, neopterin, levels were signifi-cantly higher and nesfatin-1 levels were significantly lower in the HT group compared to the control group. Statistically significant differences were observed between all the groups except euthyroid HT versus HT treated with levothyroxine for nesfatin-1 at the 0.05 level.Conclusion: IL-17, IL-23, and neopterin were involved in the etiopathogenesis of HT. Weight gain in HT may due to low nesfatin-1 level rather than throid hormone deficiency. These variables could be used as potential biomarkers in the diagnosis, prognosis and fellow up of HT disease.Öğe Analysis of serum cytokine and protective vitamin D levels in severe cases of COVID-19(Wiley, 2022) Bayraktar, Nihayet; Turan, Hamdiye; Bayraktar, Mehmet; Ozturk, Ali; Erdogdu, HamzaIn this study, we investigated the role and relationship between the cytokine profile and protective vitamin D by measuring their serum levels in COVID-19 intensive care unit patients with severe illnesses. A total of 74 patients were included in our study. Patients were divided into two groups. Patients in the COVID-19 group (n = 31) and individuals without a history of serious illness or infection were used as the control group (n = 43). The serum concentrations of interleukin-1 (IL-1), IL-6, IL-10, IL-21, and tumor necrosis factor-alpha (TNF-alpha) were measured by enzyme-linked immunosorbent assays. Levels of serum vitamin D were detected with Liquid chromatography-mass spectrometry methodologies. TNF-alpha, IL-1, IL-6, IL-10, IL-21, and vitamin D levels were measured in all patients. The serum cytokine levels in the COVID-19 patient group were significantly higher (151.59 +/- 56.50, 140.37 +/- 64.32, 249.02 +/- 62.84, 129.04 +/- 31.64, and 123.58 +/- 24.49, respectively) than control groups. Serum vitamin D was also significantly low (6.82 +/- 3.29) in patients in the COVID-19 group than the controls (21.96 +/- 5.39). Regarding the correlation of vitamin D with cytokine levels, it was significantly variable. Our study shows that COVID-19 patients are associated with lower serum vitamin D and higher pro-inflammatory cytokines associated with increased virus presence. Our data provide more evidence of the anti-inflammatory effect of vitamin D on COVID-19 patients and the protective effects of vitamin D on risk were demonstrated.Öğe Antimicrobial susceptibility of bacterial pathogens isolated from healthcare workers' cellphones(Elsevier France-Editions Scientifiques Medicales Elsevier, 2021) Bayraktar, Mehmet; Kaya, Eyyup; Ozturk, Ali; Ibahim, Bashar Mohammed SalihObjective: To evaluate bacterial isolates, antibiotic susceptibility, and disease transmission risk in healthcare workers using cellphones. Methods: A total of 70 cellphones were received from the hospital staff. Samples were collected from the phones with a sterile cotton swab moistened with physiological saline solution. Samples were inoculated in a bacteriological culture medium and incubated at 37.5 degrees C for 24-48 hours. Identification of microorganisms was performed by traditional methods and VITEK 2 device. Kirby-Bauer disk diffusion method was used to determine antibiotic susceptibility. Results: A total of 26 species and 170 microorganisms were isolated from 66 cellphones from which bacterial growths were obtained: coagulase-negative staphylococci (n = 63, 37%) (most commonly-Staphylococcus epidermidis: 25/63), Micrococcus luteus (n = 25, 14.7%), Tetracoccus (n = 24, 14.1%), Kocuria spp. (n = 24, 14.1%), Corynebacterium diphtheriae (n = 7, 4.1%), Leuconostoc mesenteroides (n = 5, 3.0%), S. aureus (n = 4, 2.3%), Enterococcus spp. (n = 5, 2.9%), Acinerobacter spp. (n = 7, 4.1%), Klebsiella pneumoniae (n = 2, 1.2%), Actinomyces spp. (n = 1, 0.6%), Pseudomonas aeruginosa (n = 1, 0.6%), Morganella morgardi (a = 1, 0.6%), and Alcaligenes faecalis (a = 1, 0.6%). Gram-positive isolates were all susceptible to the antibiotics used, whereas Gram-negative isolates were all resistant to ceftazidime. Conclusion: Hands and/or cellphones of healthcare staff can be contaminated with various types of microorganisms. We recommend proper hand washing and disinfection to prevent bacterial pathogens spread within the hospital.Öğe Biological evaluation of Schiff bases containing dopamine as antibacterial/antifungal and potential Anti COVID-19 agents: Design, synthesis, characterization, molecular docking studies, and ADME properties(Elsevier, 2023) Unlu, Ayse; Ozmen, Ummuhan Ozdemir; Alyar, Saliha; Ozturk, Ali; Alyar, Hamit; Gunduzalp, Ayla BalabanIn this study, Schiff bases containing dopamine were synthesized and their antimicrobial activities were investigated in vitro. What makes this study unique is the use of dopamine as a starting compound, which has not been previously explored for the synthesis of Schiff bases with acetophenone substituents. These newly synthesized compounds exhibit important pharmacological properties, and their structures have been thoroughly characterized using elemental analysis, 1H NMR, 13C NMR, and FT-IR methods. In the next phase of the study, we evaluated the antimicrobial activities of these dopamine Schiff bases against seven different bacterial and fungal isolates. Remarkably, one compound, 5NO2-afdop, demonstrated exceptionally high antibacterial activity (MIC: 0.078 & mu;g/ml) against Gram-positive bacteria, namely Staphylococcus aureus and Staphylococcus epidermis. Its activity was even superior to that of the reference drugs sulfisoxazole and sulfamethoxazole (MIC: 0.312 & mu;g/ml). This finding highlights the potential of the synthesized compound as a promising antimicrobial agent. Moreover, in-silico studies, the 5NO2-afdop compound shows comparable activity against the major protease of SARS-CoV2, the virus responsible for the COVID-19 pandemic. To assess the drug-likeness of all synthesized compounds, we employed the five Lipinski rules and conducted ADME predictions. These analyses provided valuable insights into the compounds' pharmacological profiles, suggesting their potential as drug candidates.. Additionally, molecular docking studies shed light on the interactions between the synthesized compounds and their target proteins. Notably, 5NO2-afdop exhibited the strongest antibacterial activity against the S. aureus protein (PDB ID: 4FGD) and displayed promising antiviral activity against the SARS-CoV-2 major protease (PDB ID: 5R80). These docking results further support the potential of 5NO2-afdop as a dual-action compound with antibacterial and antiviral properties.Öğe Comparative Analysis of the Effect of Different Nucleic Acid Extraction Methods on SARS-CoV-2 Quantitative Real-Time Reverse Transcription Polymerase Chain Reaction Results(Ankara Microbiology Soc, 2023) Bozok, Taylan; Ozturk, AliSevere acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is the causative agent of Coronavirus diseases-2019 (COVID-19) disease. Rapid and accurate detection of the virus is vital to prevent transmission and effectively manage the pandemic. The gold standard diagnostic method for this agent is the real-time reverse transcription polymerase chain reaction (qrRT-PCR) test conducted on respiratory tract samples and one of the most critical steps affecting the sensitivity of this test is the nucleic acid extraction stage. However, restrictive factors such as reagent supply and storage conditions limit the testing capacity. Therefore, innovative and cost-effective alternatives are needed to speed up testing and minimize pre-processing steps. The aim of this study was to evaluate the impact and applicability of different methods to enhance the efficiency of the nucleic acid extraction stage in the SARS-CoV-2 qrRT-PCR test. As an alternative to the routinely used viral nucleic acid extraction buffer (vNAT), the modified vNAT method (MvNAT), which includes centrifugation, the R1-R2 kit and the heat treatment (HT) method, was applied to 118 respiratory tract samples. Samples determined with threshold cycle values of (Cq) of <= 35 (n= 10), > 35 (n= 42), indeterminate (n= 56) in routine results and negative controls (n= 10) were included in the study. The RNA quantities obtained after extraction for each method were measured and recorded using a spectrophotometric measurement device. All samples were processed using the SARS-CoV-2 qrRT-PCR kit targeting the RdRp region. The results were statistically analyzed using unpaired and paired t-tests and results with a p-value of < 0.05 were considered statistically significant. Excluding negative control samples, while the standard method yielded a Cq value of 48.1% (mean Cq value (Cq(mean))= 39.5 +/- 6.9) for a total of 108 samples, the MvNAT method produced a Cq value of 11.1% (Cq(mean)= 38.4 +/- 5.2), the R1-R2 kit yielded 14.8% (Cq(mean)= 35.9 +/- 7.1) and HT method resulted in 25% (Cq(mean)= 31.4 +/- 6.3). When the variability in target gene Cq values was analyzed in all samples compared to the standard method, the HT method significantly provided lower Cq values (n= 16; p= 0.007; paired t-test) while the MvNAT method and R1-R2 kit yielded higher Cq values (n= 6; p= 0.025, n= 11; p= 0.004; paired t-test). Sensitivity rates were MvNAT= 31.6%, R1-R2= 57.9%, HT= 84.2%, with 100% specificity for all three methods. The HT method demonstrated a positive extraction efficiency because it is fast, easy and not dependent on reagents. Although this method provided lower Cq values than the standard method, especially in samples with a high viral load, it should be considered that it also has the potential to yield false-negative results in samples with Cq> 35. With this study, it was concluded that the extraction phase of the SARS-CoV-2 qrRT-PCR test can be carried out using various methods that do not require kits or reagents, such as the HT method. However, it is believed that multicenter studies involving a larger number of samples are necessary to standardize the test and assess the possibility of false negatives.Öğe COVID-19-associated pulmonary aspergillosis (CAPA): identification of Aspergillus species and determination of antifungal susceptibility profiles(Springer, 2023) Ozturk, Ali; Bozok, Taylan; Erdogan, Merve; Ibrahim, Bashar M. S.; Bozok, Tugce SimsekAmong the co-infectious agents in COVID-19 patients, Aspergillus species cause invasive pulmonary aspergillosis (IPA). IPA is difficult to diagnose and is associated with high morbidity and mortality. This study is aimed at identifying Aspergillus spp. from sputum and tracheal aspirate (TA) samples of COVID-19 patients and at determining their antifungal susceptibility profiles. A total of 50 patients with COVID-19 hospitalized in their intensive care units (ICU) were included in the study. Identification of Aspergillus isolates was performed by phenotypic and molecular methods. ECMM/ISHAM consensus criteria were used for IPA case definitions. The antifungal susceptibility profiles of isolates were determined by the microdilution method. Aspergillus spp. was detected in 35 (70%) of the clinical samples. Among the Aspergillus spp., 20 (57.1%) A. fumigatus, six (17.1%) A. flavus, four (11.4%) A. niger, three (8.6%) A. terreus, and two (5.7%) A. welwitschiae were identified. In general, Aspergillus isolates were susceptible to the tested antifungal agents. In the study, nine patients were diagnosed with possible IPA, 11 patients were diagnosed with probable IPA, and 15 patients were diagnosed with Aspergillus colonization according to the used algorithms. Serum galactomannan antigen positivity was found in 11 of the patients diagnosed with IPA. Our results provide data on the incidence of IPA, identification of Aspergillus spp., and its susceptibility profiles in critically ill COVID-19 patients. Prospective studies are needed for a faster diagnosis or antifungal prophylaxis to manage the poor prognosis of IPA and reduce the risk of mortality.Öğe Distribution of clinical Candida species and their susceptibility to antifungal agents(Lippincott Williams & Wilkins, 2021) Tumer, Seray; Bayraktar, Mehmet; Ozturk, AliBackground: The incidence of fungal infections, especially by Candida species, has increased in recent years. This study was designed to isolate and identify Candida species from various clinical samples, and to examine their susceptibility to antifungal agents. Methods: A total of 175 Candida species were isolated from different clinical samples, and were identified using germ tube test, Cornmeal agar, and API C 20 AUX and VITEK 2 Compact Systems. Antifungal susceptibility of these isolates was determined using ATB Fungus 3 strip and VITEK 2 antifungal susceptibility cards. The results of these two methods were comparatively assessed. Results: A total of 175 Candida strains were isolated from 114 (65.1%) urine, 42 (24%) blood, eight (4.6%) sputum, seven (4%) endotracheal, and four (2.3%) wound samples. Of isolated Candida species, 102 (58.2%) were Candida albicans, 31 (17.6%) Candida tropicalis, 17 (9.6%) Candida parapsilosis, 13 (7.4%) Candida glabrata, three (1.8%) Candida kefyr, three (1.8%) Candida krusei, two (1.2%) Candida lusitaniae, and one (0.6%) Candida famata. By VITEK 2 antifungal susceptibility cards, the overall resistance rates were 0.6% to each of amphotericin B and 5-flucytosine, and 1.8% to fluconazole. In ATB Fungus 3 strip, the resistance (1.8%) was observed only to fulconazole. All isolates were uniformly susceptible to voriconazole in both methods. Conclusion: Valuable information and data on distribution and susceptibility of Candida strains were obtained. These data may be valuable from epidemiological point of view as well as for proper and optimal therapy of Candida infections in our region (Sanliurfa, Turkey). Copyright (C) 2021 Wolters Kluwer Health, Inc. All rights reserved.Öğe Evaluation of rapid antibody test and chest computed tomography results of COVID-19 patients: A retrospective study(Wiley, 2021) Ozturk, Ali; Bozok, Taylan; Simsek Bozok, TugceThe purpose of this study was to evaluate the SARS-CoV-2 immunoglobulin M/immunoglobulin G (IgM/IgG) rapid antibody test results in symptomatic patients with COVID-19 and their chest computed tomography (CT) data. A total of 320 patients admitted to our hospital for different durations due to COVID-19 were included in the study. Serum samples were obtained within 0-7 days from COVID-19 patients confirmed by reverse-transcription polymerase chain reaction (RT-PCR) and chest CT scan. According to the SARS-CoV-2 RT-PCR results, the patients included in the study were divided into two groups: PCR positive group (n = 46) and PCR negative group (n = 274). The relationship between chest CT and rapid antibody test results were compared statistically. Of the 320 COVID-19 serum samples, IgM, IgG, and IgM/IgG were detected in 8.4%, 0.3%, and 11.6% within 1 week, respectively. IgG/IgM antibodies were not detected in 79.7% of the patients. In the study, 249 (77.8%) of 320 patients had positive chest CT scans. Four (5.6%) of 71 patients with negative chest CT scans had IgM and two (2.8%) were both IgM/IgG positive. IgM was detected in 23 (9.2%), IgG in one (0.4%), and IgM/IgG in 35 (14%) of chest CT scan positive patients. The rate of CT findings in patients with antibody positivity was found to be significantly higher than those with antibody negativity. The results of the present study show the accurate and equivalent performance of serological antibody assays and chest CT in detecting SARS-CoV-2 within 0-7 days from the onset of COVID19 symptoms. When RT-PCR is not available, we believe that the combination of immunochromatographic test and chest CT scan can increase diagnostic sensitivity for COVID-19.Öğe Evaluation of the Relationship Between Aquaporin-1, Hepcidin, Zinc, Copper, and Iron Levels and Oxidative Stress in the Serum of Critically Ill Patients with COVID-19(Springernature, 2022) Bayraktar, Nihayet; Bayraktar, Mustafa; Ozturk, Ali; Ibrahim, BasharOur study aims to determine the relationship between hepcidin, aquaporin (AQP-1), copper (Cu), zinc (Zn), iron (Fe) levels, and oxidative stress in the sera of seriously ill COVID-19 patients with invasive mechanical ventilation. Ninety persons with and without COVID-19 were taken up and separated into two groups. The first group included seriously COVID-19 inpatients having endotracheal intubation in the intensive care unit (n = 45). The second group included individuals who had negative PCR tests and had no chronic disease (the healthy control group n = 45). AQP-1, hepcidin, Zn, Cu, Fe, total antioxidant status (TAS), and total oxidant status (TOS) were studied in the sera of both groups, and the relations of these levels with oxidative stress were determined. When the COVID-19 patient and the control groups were compared, all studied parameters were found to be statistically significant (p < 0.01). Total oxidant status (TOS), oxidative stress index (OSI), and AQP-1, hepcidin, and Cu levels were increased in patients with COVID-19 compared to healthy people. Serum TAC, Zn, and Fe levels were found to be lower in the patient group than in the control group. Significant correlations were detected between the studied parameters in COVID-19 patients. Results indicated that oxidative stress may play an important role in viral infection due to SARS-CoV-2. We think that oxidative stress parameters as well as some trace elements at the onset of COVID-19 disease will provide a better triage in terms of disease severity.Öğe In vitro antifungal and antibiofilm activities of novel sulfonyl hydrazone derivatives against Candida spp.(Masson Editeur, 2023) Aydin, Merve; Ozturk, Ali; Duran, Tugce; Ozmen, Ummuhan Ozdemir; Sumlu, Esra; Ayan, Esra Bilen; Korucu, Emine NedimeBackground: The aim of this study was to investigate the antifungal and antibiofilm activity of the new sulfo-nyl hydrazones compound derived from sulphonamides.Methods: In this study, new sulfonyl hydrazone series were synthesized via a green chemistry method. The structures of the synthesized compounds were characterized by elemental analyses and spectroscopic meth-ods. The antifungal activities of the Anaf compounds against Candida strains under planktonic conditions were tested. The biofilm-forming ability of Candida strains was determined and the inhibitory effects of Anaf compounds on Candida biofilms compared with fluconazole were measured by MTT assay. Expression analy-sis of biofilm-related genes was investigated with qRT-PCR. The statistical analysis was performed using a one-way ANOVA test.Candida: strains was determined and the inhibitory effects of Anaf compounds on Candida biofilms compared with fluconazole were measured by MTT assay. Expression analysis of biofilm-related genes was investigated with qRT-PCR. The statistical analysis was performed using a one-way ANOVA test. Results: A total of 16 (45.7%) out of 35 Candida isolates were determined as strong biofilm producers in this study. C. albicans was the most biofilm producer, followed by C. krusei and C. lusitaniae. The Anaf compounds had a broad spectrum of activity with MIC values ranging from 4 mg/ml to 64 mg/ml. Our data indicated that the Anaf compound had a significant effect on inhibiting biofilm formation in both fluconazole-susceptible and-resistant strains. The expression levels of hypha-specific genes als3, hwp1, ece1 and sap5 were downre-gulated by Anaf compounds.Conclusions: Our study revealed that the Anaf compounds had antifungal activity and inhibited fungal bio-films, which may be related to the suppression of C. albicans adherence and hyphal formation. These results suggest that Anaf compounds may have therapeutic potential for the treatment and prevention of biofilm-associated Candida infections.(c) 2022 SFMM. Published by Elsevier Masson SAS. All rights reserved.Öğe Investigation of Antifungal Activities of Some Disinfectants on Candida albicans(Ankara Microbiology Soc, 2018) Ozturk, Ali; Kalkanci, AyseDisinfectants may have fungicidal or fungistatic effects against fungal cells. The mechanism of action of disinfectants on fungal cells believed to be similar to the antibacterial activity. The aim of this study was to demonstrate the efficacy of some disinfectants against Candida albicans and to investigate the relationship between virulence and disinfectant resistance. In this study, the susceptibility of 417 clinical C.albicans and reference isolates against disinfectants were determined. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values of disinfectants were obtained by using broth microdilution (BMD) assay. Epidemiological cut-off values (ECVs) were determined by using the MIC and MFC values. Crystal violet assay was carried out to investigate membrane permeability in disinfectant resistant and susceptible isolates. Rhodamine 6G (R6G) flourescence stain was used to show the increase in the number of efflux pumps among selected isolates. The relationship between virulence and disinfectant resistance was determined by in vitro and in vivo investigations. Virulence factors secretory acid proteinase (SAP), phospholipase, esterase, hemolytic activity and slime factor production were examined in vitro. In vivo virulence assay was performed by infecting Galleria mellonella larvae. The relationship between virulence factors and disinfectant resistance was evaluated according to the mortality rates of G.mellonella larvae. The range of MIC values for benzalkonium chloride (BZC) and chlorhexidine digluconate (CHX), triclosan (TRC) and sodium hypochlorite (SHC) were 0.25-8 mg/L, 0.06-4 mg/L and 256-16.384 mg/L, respectively. ECV values for BZC, CHX, TRC and SHC were determined as 4, 2, 1 and 4096 mg/L, respectively. The rate of crystal violet uptake was found between 26.5-57.6% for disinfectant susceptible isolates, and between 33-79.2% for resistant isolates. It is concluded that the disinfectant resistance was related with efflux pumps. Due to the lack of number of isolates that were used in this assay, the relationship between disinfectant resistance and virulence factors could not be assessed. There was no difference in the mortality of larvae infections caused by disinfectant resistant and susceptible isolates. As a result, in this study, resistant isolates against BZC, CHX, SHC and TRC were found among 417 isolates. Input and output of disinfectants were found to be associated with the cell membrane efflux pumps of C.albicans.Öğe Investigation of the Effect of Farnesol on Biofilm Formation by Candida albicans and Candida parapsilosis Complex Isolates(Ankara Microbiology Soc, 2024) Erdal, Berna; Baylan, Bensu; Batar, Bahadir; Ozturk, Ali; Topcu, BirolThe incidence of infections caused by Candida species has significantly increased over the past three decades. Candida albicans is commonly recognized as the primary causative agent in cases of candidiasis; however, non-albicans Candida species, including Candida parapsilosis, are also frequently defined as pathogens. Treatment -resistant infections arise as a result of biofilm formation, which is one of the effective mechanisms in the pathogenesis of Candida infections. However, the mechanisms of action of farnesol, a quorum sensing (QS) system molecule, on biofilm formation by Candida species remain unclear. This study aimed to demonstrate the changes in the biofilm biomass of C.albicans and C.parapsilosis complex isolates in the presence of farnesol and reveal the expression of the EFG1 and BCR1 genes, which are believed to play a role in the production of QS molecules, using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) analysis. C.albicans (n= 91) and C.parapsilosis complex (n= 29) isolates obtained from different clinical samples were included in the study. The minimum inhibitory concentration (MIC) values of farnesol were determined using the broth microdilution method according to the M27 -A3 protocol of the Clinical and Laboratory Standards Institute (CLSI). The biofilm biomass of the isolates was examined without farnesol and at the MIC-0 and MIC-2 concentrations of farnesol. Changes in the expression of the biofilm-associated EFG1 and BCR1 genes were investigated using qRT-PCR. According to the results of the study, the MIC values of farnesol were detected in the range of 1-2 mM in 82.4% (n= 75) of the C.albicans isolates and in the range of 0.5-1 mM in 72.4% (n= 21) of the C.parapsilosis complex isolates. Of the C.albicans isolates, 27 (29.7%) exhibited a strong biofilm formation and 58 (63.7%) demonstrated a weaker biofilm formation, while these rates were 34.4% (n= 10) and 62.1% (n= 18), respectively, for the C.parapsilosis complex isolates. At the MIC-0 and MIC-2 concentrations, farnesol was observed to reduce biofilm biomass among C.albicans (n= 24, 88.9%) and C.parapsilosis complex (n= 8, 80.0%) isolates that formed strong biofilms and observed to increase biofilm biomass among those that formed weak biofilms [60.3% (n= 35) and 55.6% (n= 10), respectively]. On completion of the qRT-PCR analysis supporting the results of the biofilm experiment, it was determined that the expressions of the EFG1 and BCR1 genes decreased at the MIC-0 and MIC-2 concentrations of farnesol among the strong biofilm-forming C.albi- cans and C.parapsilosis complex isolates, but there was an increase in gene expressions among the weak biofilm-forming isolates. In addition to the antifungal effect of farnesol on Candida species, this study provided data on the efficacy of the MIC-0 and MIC-2 concentrations of farnesol against Candida biofilm biomass. Although our results suggest that farnesol can be used as an alternative agent to reduce biofilm formation in Candida infections, they need to be supported by further studies. Moreover, this research has significance as it represents the first study to determine the EFG1 and BCR1 gene expressions among C.parapsilosis complex isolates in the presence of farnesol.Öğe NEW SULFONYLHYDRAZONES CONTAINING METHANE SULFONIC ACID HYDRAZIDE HAVING HUMAN ANTI-CARBONIC ANHYDRASE AND ANTI- MICROBIAL ACTIVITY: SYNTHESIS, SPECTROSCOPIC CHARACTERIZATION, ELECTROCHEMICAL PROPERTIES, AND BIOLOGICAL ACTIVITIES(Soc Chemists Technologists Madeconia, 2021) Uzun, Demet; Erdogdu, Ebru; Gunduzalp, Ayla Balaban; Ozdemir, Ummuhan Ozmen; Ozturk, Ali; Ozbek, Neslihan; Kaya, KeremIn this work, new sulfonylhydrazones nomenclatured as 3,5-ditertbutylsalicylaldehyde methanesulfonylhydrazone (II), 3-tertbutylsalicylaldehyde methanesulfonylhydrazone (III), and 5-bromosalicylaldehyde methanesulfonylhydrazone (IV) were synthesized by the reaction of methanesulfonicacidhydrazide (I) with 3,5-ditertbutylsalicylaldehyde, 3-tertbutylsalicyl aldehyde, and 5-bromosalicylaldehyde. The structures of the aromatic sulfonylhydrazones were determined by using elemental analysis, UV-Vis, FT-IR, H-1-NMR, and C-13-NMR methods. The structure of IV was also supported with the X-ray diffraction method. Sulfonamides were generally investigated for their inhibitory effects on human carbonic anhydrase isoenzymes (hCAs). Synthesized alkylsulfonylhydrazones have a sulfonamide group, which is the most important pharmacophore for the carbonic anhydrase (CA) inhibition efficiency like the reference agent acetazolamide (AAZ). The enzyme inhibition trends of alkylsulfonylhydrazones on the hCA I isoenzyme were qualitatively investigated by cyclic voltammetry (CV) and differantial pulse voltammetry (DPV). Also, the inhibition activities of sulfonylhydrazones were determined by using UV-Vis spectrophotometry, and their inhibition parameters, such as K-m, IC50, and K-i, were calculated. Among the tested compounds, IV was found to be the most active compound on the hCA I isoenzyme with an IC50 value of 4.86x10(-6) M, whereas II and III were found to be the least potent compounds on hCA I with an IC50 value of 3.96x10(-4) M and 5.58x10(-5) M, respectively. All of the compounds showed excellent inhibition activity against gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Stenotrophomonas maltophilia) and gram-positive bacteria (Staphylococcus aureus, Staphylococcus epidermidi), with minimum inhibitory concentration (MIC) values less than that of standard drugs (sulfamethoxazole and sulfisoxazole). In addition, all of the compounds exhibited excellent antifungal inhibition against C. albicans and A. fumigatus, with MIC values of 8-16 mu g/ml, which were 2-4 fold higher than the standard drug fluconazole (32 mu g/ml).Öğe Repeated use of fibrin sealants kept at room temperature in conjunctival autografting: An animal study(Wolters Kluwer Medknow Publications, 2022) Zor, Kursad Ramazan; Cinaroglu, Selim; Kucuk, Erkut; Keles, Haci; Ozturk, AliPurpose: In this study, our aim was to investigate if fibrin adhesives used in conjunctival wound surgery with autologous conjunctival grafts could be used repeatedly at different times after surgical opening. Methods: 40 New Zealand rabbits were used in the study. These animals were divided into four groups, each consisting of 10 rabbits, and hence 20 eyes. In the first group (control group), Tisseel fibrin sealant was used on the day the eye was first opened surgically; in the second group, it was used on the seventh day; on the third group, it was used on the 14th day; and in the fourth group, it was used 28 days after surgical opening. The graft from the inferior bulbar conjunctiva was attached using Tisseel fibrin glue to the superior scleral bed at the location where the superior bulbar conjunctiva was excised in the same eye. Results: No microbial growth was detected in the cultures of the samples tested. There were two partial graft loss in group 2 and there was one partial graft loss in each group of the other groups, and further total graft loss was present in one rabbit in group 3. None of the rabbits had any complications like granuloma, Corneal dellen or infection. Conclusion: Based on these results, fibrin sealants can be used repeatedly by storing them at room temperature. Repeated use of fibrin adhesives will reduce the cost of ophthalmologic surgeries and non-ophthalmologic surgeries.Öğe Synthesis and biological studies of novel hydroxyacetophenone-tetrazole hybrids(Acg Publications, 2023) Disli, Ali; Yucesoy, Esin Eylem; Ozturk, Ali; Dilek, GulayA series of novel hybrid compounds was synthesized where 2 '-hydroxyacetophenone and N-alkylated thiotetrazole were coupled via methylene spacers of different lengths. The structures of the compounds were characterized by spectroscopic techniques, including the 1H-and 13C-NMR, FT-IR, and HRMS methods. The antimicrobial activities of the title compounds were evaluated against clinical isolates of Gram-positive and negative bacterial and fungal species. All compounds showed a broad spectrum of antimicrobial activity and inhibited all bacteria and fungi that tested with MIC values ranging from 4 to 128 mu g/ml. 4a and 5d were the most active antibacterial members.Öğe Synthesis, characterization, theoretical studies and antimicrobial activity of novel 1-(2-hydroxy-4-propoxy-3-propylphenyl)ethanones bearing thiotetrazole(Elsevier, 2021) Disli, Ali; Yucesoy, Esin Eylem; Erdogdu, Yusuf; Gulluoglu, Mehmet Tahir; Ozturk, Ali; Dilek, GulayWe report herein a joint experimental and theoretical investigation on the novel 1-(2-hydroxy-4-propoxy-3-propylphenyl)ethanone bearing 1-propyl-1H-tetrazol-5-thiol and 2-propyl-2H-tetrazole-5-thiol pharmacophores. In the experimental studies, 1-[4-(34(1-propyl-1H-tetrazol-5-y1)thio)propoxy)2-hydroxy-3-propylphenyliethanone and 1-[4-(34(2-propyl-2H-tetrazol-5-yl)thio)propoxy)-2-hydroxy-3propylphenyliethanone were synthesized and characterized by ATR-FTIR, (1) H NMR, C-13-APT, and HRMS. In the theoretical studies, the most stable conformations, vibrational and NMR spectra of these compounds were predicted by Quantum chemical calculations. Quantum chemical calculations were performed using the B3LYP functional with 3-21 G, and 6-311++G(d,p) basis sets. All quantum chemical calculations were utilized Gaussian 16 software. While torsional barriers of the compounds were determined by B3LYP/3-21 G, their geometry optimizations were performed by B3LYP functional with 3-21 G, and 6-311++G(d,p) basis sets. The harmonic vibrational frequencies, potential energy distribution (PED) and infrared intensities were predicted using the B3LYP/6-311++G(d,p). Theoretically predicted vibrational frequencies were compared with experimental results. Predicted NMR chemical shifts were obtained by the GIAO method using the B3LYP/6-311++G(d,p). The (1) H and (13) C experimental chemical shifts are consistent with the theoretical NMR chemical shift values. Antimicrobial activities of the title compounds were investigated against five bacterial strains (Staphylococcus aureus, Staphylococcus epidennidis, Escherichia coli, Pseudomonas aeruginosa, Stenotrophomonas maltophilia) and two fungal strains (Candida albicans, Aspergillus fumigatus). The compounds showed good antimicrobial activity and inhibited all tested bacteria and fungi. (C) 2021 Elsevier B.V. All rights reserved.Öğe What is the novel coronavirus disease 2019 (COVID-19) that paralyze the world?(Lippincott Williams & Wilkins, 2020) Ozturk, Ali; Abdulmajed, Olkar; Ibrahim, BasharThe outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 infection has recently spread worldwide was declared a pandemic on March 11. The most common symptoms of COVID-19 disease are fever, fatigue, and dry cough. Some patients may experience pain and aches, nasal congestion, cold, sore throat or diarrhea. These symptoms are usually mild and begin gradually. Currently, the source of the virus is still unknown. However, all available evidence indicates that the origin of this virus is a natural animal and that it is not a manufactured virus. The virus spreads faster than its two ancestors the severe acute respiratory syndrome coronavirus and Middle East Respiratory Syndrome Coronavirus. The effects of COVID-19 disease on people are that the elderly and people with preexisting medical conditions (such as hypertension, heart disease, and diabetes) have more severe symptoms than others. Some potential vaccines and drugs specifically needed to treat this disease are being investigated and are being tested by clinical trials. Copyright (C) 2020 Wolters Kluwer Health, Inc. All rights reserved.
