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Now showing 1 - 7 of 7
  • PublicationMetadata only
    Antimicrobial resistance of Helicobacter pylori strains to five antibiotics, including levofloxacin, in Northwestern Turkey
    (2015-05-01T00:00:00Z) Caliskan, Reyhan; Tokman, Hrisi Bahar; Erzin, Yusuf; Saribas, Suat; Yuksel, Pelin; Bolek, Bora Kazim; Sevuk, Ecehan Ozge; Demirci, Mehmet; Yilmazli, Ozge; Akgul, Ozer; Kalayci, Fatma; Cakan, Huseyin; Salih, Barik; Bal, Kadir; Kocazeybek, Bekir; YÜKSEL MAYDA, PELİN
    Introduction: Antibiotic resistance is the main factor that affects the efficacy of current therapeutic regimens against Helicobacter pylori. This study aimed to determine the rates of resistance to efficacy clarithromycin, amoxicillin, tetracycline, levofloxacin and metronidazole among H. pylori strains isolated from Turkish patients with dyspepsia. Methods: H. pylori was cultured from corpus and antrum biopsies that were collected from patients with dyspeptic symptoms, and the antimicrobial susceptibility of H. pylori was determined using the E-test (clarithromycin, amoxicillin, tetracycline, metronidazole and levofloxacin) according to the EUCAST breakpoints. Point mutations in the 23S rRNA gene of clarithromycin-resistant strains were investigated using real-time PCR. Results: A total of 98 H. pylori strains were isolated, all of which were susceptible to amoxicillin and tetracycline. Of these strains, 36.7% (36/98) were resistant to clarithromycin, 35.5% (34/98) were resistant to metronidazole, and 29.5% (29/98) were resistant to levofloxacin. Multiple resistance was detected in 19.3% of the isolates. The A2143G and A2144G point mutations in the 23S rRNA-encoding gene were found in all 36 (100%) of the clarithromycin-resistant strains. Additionally, the levofloxacin MIC values increased to 32 mg/L in our H. pylori strains. Finally, among the clarithromycin-resistant strains, 27.2% were resistant to levofloxacin, and 45.4% were resistant to metronidazole. Conclusions: We conclude that treatment failure after clarithromycin-or levofloxacin-based triple therapy is not surprising and that metronidazole is not a reliable agent for the eradication of H. pylori infection in Turkey.
  • PublicationOpen Access
    Neopterin and Soluble CD14 Levels as Indicators of Immune Activation in Cases with Indeterminate Pattern and True Positive HIV-1 Infection.
    Background: We aimed to evaluate the roles of the plasma immune activation biomarkers neopterin and soluble CD14 (sCD14) in the indirect assessment of the immune activation status of patients with the indeterminate HIV-1 (IHIV-1) pattern and a true HIV-1-positive infection (PCG). Methods: This cross-sectional and descriptive study included eighty-eight patients with the IHIV-1 pattern, 100 patients in the PCG, and 100 people in a healthy control group (HCG). Neopterin and sCD14 levels were determined by competitive and sandwich ELISA methods, respectively. Results: Mean neopterin and sCD14 levels among those with the IHIV-1 pattern were significantly lower than among the PCG (p < 0.001 and p = 0.001, respectively), but they were similiar to those in the HCG (p = 0.57 and p = 0.66, respectively. Mean neopterin and sCD14 levels among the PCG were found to be significantly higher than among those with the IHIV-1 pattern (p < 0.001 and p = 0.001, respectively) and among those in the HCG (p = 0.001, p < 0.001, respectively). Neopterin did not have adequate predictive value for identifying those in the PCG (area under the curve [AUC] = 0.534; 95% CI, 0.463-0.605; p = 0.4256); sCD14 also had poor predictive value but high specificity (100%) for identifying those in the PCG (AUC = 0.627; 95% CI, 0.556-0.694; p = 0.0036). Conclusions: While low levels of these two biomarkers were detected among those with the IHIV-1 pattern, they were found in high levels among those in the PCG. These two markers obviously cannot be used as a sceening test because they have low sensitivies. Taken together, we suggest that neopterin and sCD14 may be helpful because they both have high specificity (92%-100%) as indirect non-specific markers for predicting the immune activation status of individuals, whether or not they have true positive HIV-1.
  • PublicationMetadata only
    Is the incidence of clostridium difficile in nosocomial diarrhoea underestimated?
    (2017-07-01T00:00:00Z) Akgül, Özer; Sapmaz, Burcu; ÇATAL, Fadimana; Yüksel, PELİN; Çalişkan, Reyhan; Karasakal, Ömer Faruk; UYSAL, Hayriye Kirkoyun; YÜKSEL MAYDA, PELİN
  • PublicationOpen Access
    Diagnostic performance of the RT-qPCR method targeting 85B mRNA in the diagnosis of pulmonary Mycobacterium tuberculosis infection
    (2018-09-01T00:00:00Z) Demirci, Mehmet; Saribas, Suat; Ozer, Nigar; TOPRAK, Sezer; CAGLAR, Emel; ORTAKOYLU, Gonenc; Yuksel, PELİN; Ayaz, Gulsel; Tokman, Hrisi B.; Uysal, Omer; Dinc, HARİKA ÖYKÜ; ZİVER, Tevhide; Kocazeybek, Bekir; YÜKSEL MAYDA, PELİN; UYSAL, ÖMER; DİNÇ, HARİKA ÖYKÜ
    Background: Several nucleic acid amplification techniques (IS6110, 16S rRNA, and 85B mRNA) were developed for the rapid, direct detection of Mycobacterium tuberculosis. We aimed to assess the diagnostic performance of 85B mRNA-based RT-qPCR by comparing with the real-time PCR COBAS TagMan MTB Kit while using the BACTEC MGIT 960 method as the gold standard.
  • PublicationMetadata only
    Serum neopterin and procalcitonin levels in relationship with pediatric burn wound infections
    (2016-03-01T00:00:00Z) Pilanci, Ozgur; Ergin, Sevgi; Sirekbasan, Serhat; Ersin, Idris; Habip, Zafer; Yuksel, Pelin; Kuvat, Nuray; Aslan, Mustafa; Dinc, Oyku; Saribas, Suat; Kocazeybek, Bekir; YÜKSEL MAYDA, PELİN; DİNÇ, HARİKA ÖYKÜ
    Infection and septic complications in burn patients can be monitored by procalcitonin (PCT) and neopterin plasma values. The aim of the study was to investigate serum neopterin and PCT levels with WBC (white blood cell) and CRP (C-reactive protein) levels in patient group (PG) and healthy control group (HCG) and to investigate the relationship of these markers with burn wound infections (BWI). As the PG, 23 patients between 0-12 ages and up to 30% Total Body Surface Area (TBSA) burned and 15 HCG were included. PCT, neopterin, WBC, and CRP results on the first, the seventh, the fourteenth and the 21st day have been compared. During the follow-up period, 11 patients with BWI and 12 patients without BWI were classified as infected and non-infected patients, respectively. PCT and neopterin levels were detected higher in patients with BWI but no significant difference were present. Also, PCT and neopterin levels within the first 24 hours following the burn were detected higher in PG than HCG. CRP and WBC levels were detected high due to burn trauma. PCT and neopterin levels were increased in patients with BWI. PCT levels were increased during the pre-infectious period, while neopterin levels increased during the post-infectious period.
  • PublicationMetadata only
    Patterns of epiya motifs among cagA-positive Helicobacter pylori strains: A case–control study in a turkish population with eurasian geographical features
    (2015-10-01T00:00:00Z) Kocazeybek, Bekir Sami; Caliskan, Reyhan; Cetin, Sibel Erdamar; Ergin, Sevgi; Kuskucu, Mert; Kepil, Nuray; Dinc, HARİKA ÖYKÜ; Erzin, Yusuf Ziya; Saribas, Suat; Tokman, Hrisi Bahar; Kalayci, Fatma; Akgul, Ozer; Yuksel, Pelin; Karakullukcu, Asiye; Ziver, Tevhide; Sirekbasan, Serhat; Caglar, Erkan; Bal, Kadir; DİNÇ, HARİKA ÖYKÜ; YÜKSEL MAYDA, PELİN
    Geographical variation in the frequency of various gastroduodenal pathologies was shown to be related to the geographical diversity of H. pylori CagA Glu-Pro-lle-Tyr-Ala (EPIYA) patterns. We examined the EPIYA patterns of H. pylori and the association of EPIYA patterns with gastric cancer (GC) for the first time, to the best of our knowledge, in Turkey. The patient group (PG) contained 60 patients [38 GC and 22 duodenal ulcer (DU) patients]. The control group (CG) was 110 individuals [94 gastritis patients and 16 persons with a normal gastrointestinal system (NGIS)]. Specific primers were used for the detection of cagA including empty-site-positive and EPIYA-A, -B, -C, -D PCR. Bands of EPIYA-A, -B, -C were confirmed by DNA sequencing. One hundred and forty-two (83.5 %) strains [60 in the PG (38 GC, 22 DU), 82 in the CG (72 gastritis, 10 NGIS)] were positive for the cagA gene. EPIYA-C with multiple repeats was detected in 34 (23.9 %) strains, and 22 (64.7 %) were from GC patients. EPIYA-C with one repeat was detected in 89 (62.7 %) strains, and 54 (60.7 %) were from gastritis patients. EPIYT was detected in 10 strains, and EPIYA-D was not detected. The number of EPIYA-C with multiple repeats was significantly higher for the PG than for the CG (P<0.0001). In GC patients, the number of EPIYA-C with multiple repeats was significantly higher than one repeat (P<0.0001). In conclusion, our study showed that multiple EPIYA-C repeats increases the GC risk by 30.6-fold and the DU risk by 8.9-fold versus the CG. This indicates that Western-type H. pylori strains in Turkey have similar EPIYA motifs to those of neighbouring countries and Western populations.
  • PublicationMetadata only
    Neopterin and soluble CD14 levels as indicators of immune activation in cases with low anti-HCV reactivity and true HCV infection
    (2017-01-01) Habip, Z.; Sohrabi, P.; Saribas, S.; Caliskan, R.; Demirci, M.; Karakullukcu, A.; Atalik, K.; Yuksel, P.; Uysal, ÖMER; Kosan, E.; Tokman, H. Bahar; Kocazeybek, B.; YÜKSEL MAYDA, PELİN; UYSAL, ÖMER
    Neopterin and soluble CD14 (sCD14) are detected at high levels in hepatitis C virus (HCV) infections. We aimed to evaluate the role of these plasma immune activation biomarkers, for the indirect assessment of immune activation status of patients with low anti-HCV reactivity and a HCV infection. Low anti-HCV reactivity group (LRG, n: 70), true positive HCV infection group (THG, 30) and healthy control group (HCG, 30) were analyzed in this study. We have used ELISA, HCV RIBA/LIA and HCV-RNA methods. Mean neopterin levels were significantly lower in LRG than THG (p 0.05). Mean sCD14 were significantly higher in LRG than THG and HCG (p <0.05, p <0.001). Values of 3.95 mu g/ml and 5.36 nmol/l for sCD14 and neopterin resulted in the maximum area under the receiver operating characteristic curves (ROC), which were 0.859 (95% CI, 0.745 to 0.935; <0.0001) and 0.788 (95% CI, 0.663 to 0.883; <0.0001), respectively. These cut-offs corresponded to a sensitivity of 73.3% and a specificity of 73.3% for neopterin and of 100% and 76.7% for sCD14. Our results suggest that a specific immunoactivation might be caused by true positive HCV infection. Due to the significant results sCD14 in LRG might be non-specifically affected by some underlying atypical immunohematological pathologies. Only neopterin might be used to exclude low anti-HCV reactivity from a true HCV infection. The use of neopterin but not sCD14 in combination with fourth-generation EIA/CMIA combo tests will be useful when nucleic acid tests are not available for screening blood donors at blood banks.