Browsing by Author "Karahan, Zeynep Ceren"

Now showing 1 - 4 of 4

The Effect of Temperature and Contact Time of Sodium Hypochlorite on Human Roots Infected with Enterococcus Faecalis and Candida Albicans
(2014) Gulsahi, Kamran; Tirali, R. Ebru; Cehreli, S. Burcak; Karahan, Zeynep Ceren; Uzunoglu, Emel; Sabuncuoglu, Bizden; https://orcid.org/0000-0003-3510-7265; https://orcid.org/0000-0001-6487-3984; 23011474; AAX-5565-2021; AAD-2907-2020; AAD-6138-2021
The aim of this study was to evaluate the effectiveness of 2.5 % NaOCl at different temperature and time intervals on Enterococcus faecalis and Candida albicans-infected human roots. A total of 112 root cylinders prepared from extracted single-rooted humans were infected by E. faecalis (Group A, n = 56) or C. albicans (Group B, n = 56); 3 root cylinders served as negative controls. Both groups were further divided into 6 subgroups according to three contact times (30 s, 1 min, 5 min) with NaOCl at two different temperatures (25 or 37 A degrees C). Microorganism growth was controlled at the 24th and 48th hours. Statistical analysis was performed using the Chi-square test. While NaOCl at 25 A degrees C for 5 min was the most effective irrigation regimen to eliminate E. faecalis (p < 0.001), NaOCl at 37 A degrees C for 5 min exhibited significantly superior antifungal properties (p < 0.05). At the same contact times, difference in the temperature of NaOCl did not affect the growth of either E. faecalis or C. albicans. As a result, the irrigation time of NaOCl was more effective than the temperature to eliminate E. faecalis, while pre-heating of NaOCl to 37 A degrees C increased its effectiveness on C. albicans at 5 min contact time.
Evaluation of Blood Culture Practices: Use of System (Epicenter) Data
(2019) Basustaoglu, Ahmet; Suzuk Yildiz, Serap; Mumcuoglu, Ipek; Karahan, Zeynep Ceren; Ogunc, Dilara; Kaleli, Ilknur; Kursun, Senol; Evren, Ebru; Ozhak, Baysal Betil; Demir, Melek; Murray, Patrick; 30683035
Sepsis is a serious clinical problem and estimated to be responsible for 18 million annual deaths worldwide. Therefore, the use and the rapid processing of blood cultures are important for the transition from empiric therapy to directed therapy. The aim of this study was to assess the best blood culture practices in Turkey. We have examined the collection practices and techniques at four different hospitals, and a total of 165.443 blood culture bottles were evaluated (2013-2015). At the preanalytical phase most of the data which were important and which could support hospital quality systems/practices were not entered into the HIS and EpiCenter system. At the analytical phase loading of the bottles and removal of positive bottles primarily occurred between 6:00 and 9:00 AM but the positivity rate of the bottles showed a homogeneous distribution throughout the day. In other words, there were significant delays at processing positive blood culture bottles related to laboratory workers. The effect of education regarding best practices, transition from single bottle to two bottle cultures was successful in all hospitals. Single bottle usage decreased below 10% in all hospitals. Significantly more positive cultures were detected at multiple cultures when compared with the single bottle collection practice. In retrospective patient records, it was seen that all the laboratories reported the results of Gram staining to the clinics. However, these data were not recorded to the Epicenter. The contamination rates of Ankara Numune Hospital and Akdeniz University Faculty of Medicine Hospital are 6.2% and 5.4% respectively, contamination rates were not reported in other hospitals. The most common isolates detected in blood cultures were Escherichia coli, Klebsiella pneumoniae, Enterococcus faecium, Staphylococcus aureus, and Acinetobacter baumannii. The mean time for the detection of these organisms were less than 20 hours in the aerobic bottle and anaerobic bottles. A total of 79.6% of facultative anaerobic isolates were detected in both bottles; 9.8% were detected only in the aerobic bottles; 10.6% of the isolates were detected only in the anaerobic bottles. As a result, the educational efforts in Turkey have met with success for transition from collecting single bottle blood culture sets to two bottle blood cultures. However, further efforts are needed to increase the number of blood culture sets collected during a 24 hour's period. In addition, errors at the preanalytical, analytical and postanalytical periods (taking samples, loading bottles into the system and processing positive blood cultures) should be eliminated.
HEV Seroprevalence in Blood Donors in Turkey: Comparison of Two Commercial Anti-HEV Total Ab ELISA Kit
(2019) Yasar, Osman; Cengiz, Guniz; Karatayli, Ersin; Kizilpinar, Mehtap; Yurdcu, Esra; Albayrak, Rabia; Arslan, Onder; Karahan, Zeynep Ceren; Otlu, Baris; Guven, Aysel; Guducuoglu, Huseyin; Gokahmetoglu, Selma; Berk, Elife; Gitmisoglu, Ozlem; Sertoz, Ruchan; Yurdaydin, Cihan; Mithat, Bozdayi; Karatayli, Senem Ceren
PCR investigation of Panton-Valentine leukocidin, enterotoxin, exfoliative toxin, and agr genes in Staphylococcus aureus strains isolated from psoriasis patients
(2015) Gocmen, Julide Sedef; Sahiner, Neriman; Kocak, Mukadder; Karahan, Zeynep Ceren; 26775393
Background/aim: Staphylococcus aureus colonization is a determiner of disease activation in psoriasis patients. Here we evaluate the presence of genes encoding Panton-Valentine leukocidin (PVL), enterotoxins, TSST-1, exfoliative toxins, and the accessory gene regulatory locus by polymerase chain reaction (PCR) in S. aureus isolates obtained from healthy and diseased skin regions and anterior nares of psoriasis patients and healthy controls. Materials and methods: The presence of PVL and toxin genes was investigated, and agr typing was performed by PCR. Results: Eighteen of the isolated strains carried the sei, 1 carried the seb-sec, and 1 carried the seg enterotoxin gene. Eight of the strains carrying enterotoxin genes were isolated from nasal swabs, 6 from diseased skin swabs, and 4 from healthy skin swabs. None of the strains isolated from the control group carried the agr locus. On the other hand, 11 of the S. aureus strains isolated from the patients carried type 1, 7 carried type 1 + 3, 4 carried type 2, 4 carried type 3, and 1 carried type 1 + 2 agr loci. Conclusion: Enterotoxin production and the carried accessory gene regulatory locus may be important in the aggravation of psoriasis.