Recep Tayyip Erdoğan Üniversitesi Kurumsal Akademik Arşivi
DSpace@RTEÜ, Recep Tayyip Erdoğan Üniversitesi tarafından doğrudan ve dolaylı olarak yayınlanan; kitap, makale, tez, bildiri, rapor, araştırma verisi gibi tüm akademik kaynakları uluslararası standartlarda dijital ortamda depolar, Üniversitenin akademik performansını izlemeye aracılık eder, kaynakları uzun süreli saklar ve yayınların etkisini artırmak için telif haklarına uygun olarak Açık Erişime sunar.
Güncel Gönderiler
Investigation of the effects of antivirals used in hepatitis B treatment on blood lipid profile: a retrospective real-life data analysis
(Torino : Minerva Medica, 2026) Karabay, Oğuz; Kabukcu, Seda; Güçlü, Ertuğrul; Zerdali, Esra; Önlen, Yusuf; Yıldız, İlknur Esen; Tabak, Fehmi
Background: Entecavir (ETV), tenofovir disoproxil fumarate (TDF) and tenofovir alafenamide (TAF) are widely used in the treatment of chronic hepatitis B (CHB). This study aimed to investigate the blood lipid profile of CHB patients using these three drugs.
Methods: This Türkiye-wide retrospective cohort study included individuals who were older than 18 years of age, treatment-naive and were diagnosed with CHB for at least 1 year after 2010. The study aimed to evaluate the 48-month lipid profile changes of patients taking antivirals.
Results: In total, 1912 cases (ETV 756 [39.3%], TDF 1082 [56.3%] and TAF 74 [3.8%]) diagnosed with CHB and receiving antiviral treatment were included. There was no difference between the three drug groups in terms of age and comorbidities (P>0.05). While there was no difference in the initial total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL) and triglycerides (TG) values between the three groups, all values were significantly lower in the TDF group in the first year (P<0.05). While TG, LDL and TC values were significantly lower in the TDF group in the second year (P<0.05), there was no difference in HDL and HDL/CHOL (P>0.05).
Conclusions: TDF causes a decrease in LDL levels, TC and total cholesterol/HDL ratio. However, use of ETV and TAF did not significantly affect the lipid profile. It should not be forgotten that lipid profile changes may cause metabolic health problems in individuals receiving hepatitis B treatment and appropriate treatment should be planned by regular monitoring according to treatment groups.
Bayesian hierarchical modelling of root canal morphology in mandibular first premolars across 21 countries
(Oxford, Blackwell Scientific Publications, 2026) Hatipoğlu, Fatma Pertek; Magat, Güldane; Karobari, Mohmed Isaqali; Buchanan, Glynn Dale; Kopbayeva, Maira; Taha, Nessrin; Hatipoğlu, Ömer
Background: Understanding root canal morphology is crucial for successful endodontic treatment; however, the anatomy of mandibular first premolars (M1Ps) remains one of the most variable and challenging aspects. The Vertucci classification provides a standardised framework for describing canal configurations; however, population-level data integrating multiple countries are scarce. This study aimed to evaluate the global distribution and determinants of Vertucci canal morphology in M1Ps using a Bayesian hierarchical model.
Methods: Cone-beam computed tomography (CBCT) data of M1Ps from 21 countries were analysed. The Vertucci classification was used as the categorical outcome variable. The predictors included tooth side (34/44), voxel size, field of view (FOV), sex and age, with the country modelled as a random intercept. A Bayesian hierarchical multinomial logistic regression was fitted using the brms package (rstan backend) with weakly informative priors. Posterior estimates were expressed as odds ratios (OR) and 95% credible intervals (CrI), and model-based predicted probabilities were computed for each Vertucci type.
Results: Bayesian modelling estimated the posterior probability of Vertucci Type I configuration at 73.4% (95% CrI: 63.8%-81.5%). Non-Type I configurations showed lower but credible probabilities, including Type V (8.2%, 3.6%-15.9%), Type III (3.7%, 1.6%-7.7%), Type IV (2.9%, 1.2%-6.3%) and Type II (1.3%, 0.5%-3.1%). Unclassified canal patterns accounted for approximately one-tenth of the MnP1s (9.9%, 3.9%-19.2%). Substantial variability was observed between countries for non-Type I and unclassified configurations, whereas Type I remained consistently predominant. Sex and age exerted modest effects, whereas tooth side and field of view showed no meaningful associations. Increasing the voxel size was associated with a slight reduction in the probability of Type I and marginal increases in Type V and unclassified configurations.
Conclusions: Although Vertucci Type I configuration predominates globally in MnP1s, clinically relevant non-Type I and unclassified canal patterns occur with non-negligible frequency and vary across populations. Bayesian hierarchical modelling enables the robust quantification of anatomical heterogeneity and uncertainty, supporting more reliable cross-country comparisons and cautious interpretation of less common canal configurations.
Coenzyme Q10 protects against 6 GHz electromagnetic field-induced liver injury via suppression of inflammatory responses associated with NF-κB/p65 immunoreactivity and endoplasmic reticulum stress
(Nature Publishing Group, 2026) Akyıldız, Kerimali; Yılmaz, Hamit; Yılmaz, Adnan; Mercantepe, Tolga; Gül, Fatih; Tümkaya, Levent
We evaluated endoplasmic reticulum stress responses in hepatic tissues following 6 GHz electromagnetic field (EMF) exposure and the protective effects of Coenzyme Q10 (CoQ10). The experimental design included 24 male Sprague-Dawley rats randomly assigned to three groups: (i) sham control group, (ii) 6 GHz EMF exposure group, and (iii) 6 GHz EMF exposure + CoQ10 treatment group. Rats in the exposure groups were subjected to 6 GHz EMF exposure for 2 h/day over 30 consecutive days. Rats in the exposure groups were subjected to 6 GHz EMF exposure (0.21 mW/cm2; specific absorption rate: 0.014 W/kg) for 2 h/day over 30 consecutive days. In addition, the animals in the CoQ10 treatment group received CoQ10 orally at a dose of 10 mg/kg/day throughout the exposure period. After completing the experimental protocol, hepatic tissue samples were obtained for subsequent analyses. Comparative analyses revealed significant differences in TBARS, GSH, TNF-α, IL-1β, ALT, and AST levels across the control-6 GHz and 6 GHz -6 GHz + CoQ10 groups. Exposure to 6 GHz EMF increased histopathological damage and liver histopathological score values, whereas CoQ10 markedly reduced these changes and suppressed glucose-regulated protein 78, C/EBP homologous protein, oxidative 8-hydroxy-2'-deoxyguanosine, and nuclear factor kappa B p65immunoreactivitiesy. 6 GHz EMF induces hepatic dysfunction via oxidative stress, endoplasmic reticulum stress, inflammation, and DNA damage, whereas CoQ10 mitigates these effects of EMF exposure.
Nitrogen and water application differentially influence nutritional value and mineral content in grains of a genetically diverse sorghum germplasm collection
(BioMed Central, 2026) Bedir, Mehmet; Altaf, Muhammad Tanveer; Liaqat, Waqas; Cömertpay, Gönül; Hermans, Christian; Çatalkaya, Volkan; Baloch, Faheem Shehzad
Background: The nutritional profile of sorghum grains, such as antioxidant (AOX) status and mineral content, can be influenced by a number of environmental factors and agricultural practices, as well as by biotic and abiotic stresses. We investigated the impact of contrasting nitrogen (N) and water availability on 15 traits associated with sorghum nutritional value, including AOX capacity (AOX), total phenolics content (TPC), total protein, ash, moisture, and the concentration of 10 macronutrients [nitrogen in leaves (NCL) and grains (NCS), P, K, Mg, Ca] and micronutrients (Fe, Cu, Zn, Mn) in grains. To this end, we evaluated a broad and genetically diverse germplasm collection of 124 accessions over two years of field experiments conducted under optimal N and water availability (control, +N+FC100); under N restriction (-N+FC100); and under N and water restriction (-N+FC50).
Results: Significant effects for treatment, accession, year, and their interactions were found for most traits. In general, N and water restriction treatments were detrimental -as compared to controls- for most traits, as evidenced by decreases in mean values of 10-50% (for -N+FC100) and 8-58% (-N+FC50) consistently found for 11 traits. The most affected variables under -N+FC100 conditions were Zn, Mg, and Cu; and P, Zn, Mg under -N+FC50. In contrast, AOX and TPC levels showed increases in mean values of ~ 11-103% under -N+FC100 and -N+FC50 conditions. These two variables were moderately-to-strongly correlated (r = 0.53-0.96) across all environmental conditions and years, suggesting that phenolic compounds are the main drivers of AOX capacity in sorghum. Results from principal component analysis clearly depicted the strong effects of N-restricted and combined N plus water-restricted conditions on sorghum's nutritional and mineral contents. Genetically-stable accessions with the greatest and lowest performances for each trait and growing condition were selected for breeding purposes.
Conclusions: Nitrogen and water restrictions strongly -yet differentially- influence nutritional and mineral contents in sorghum, enhancing TPC and AOX while reducing mineral levels. This study characterized a large germplasm collection across various growing conditions and years, facilitating the selection of resilient genotypes for breeding programs aimed at improving nutritional value under changing climatic conditions.
Effect of CXCR5, PD-1 and ICOS on B-cell responses and relevance to myasthenia gravis
(Nature Publishing Grou, 2026) Çebi, Merve; Çakar, Arman; Durmuş, Hacer; Parman, Yeşil
Objectives: T follicular helper (Tfh) cells regulate B-cell responses within germinal centres primarily via programmed cell death protein 1 (PD-1) and inducible T-cell costimulator (ICOS), whereas CXC chemokine receptor type 5 (CXCR5)-negative T peripheral helper (Tph) cells provide similar support extra-follicularly. Both subsets contribute to the pathogenesis of acetylcholine receptor-antibody-positive myasthenia gravis (AChR-MG). This study investigated the roles of PD-1, ICOS and CXCR5 in T-cell-mediated B-cell activation to identify therapeutic targets for MG.
Methods: CD4 T cells from 10 healthy controls and six untreated AChR-MG patients were sorted by CXCR5, PD-1 and ICOS expression, stimulated with anti-CD3/CD28, and co-cultured with autologous CD19 B cells. Plasmablast differentiation, total AChR-IgG and cytokine productions were measured.
Results: In healthy donors, PD-1+ or ICOS+ Tph cells modestly enhanced plasmablasts and IgG production, while CXCR5+ Tfh cells co-expressing PD-1 or ICOS induced significantly stronger B-cell responses. In AChR-MG patients, PD-1 expressing T cells promoted plasmablasts, antibody production and cytokine secretion regardless of CXCR5, with amplified effects in CXCR5+ co-cultures.
Conclusions: PD-1 expression on CD4+ T cells is associated with increased B-cell helper capacity. This effect is more pronounced in Tfh-related contexts and is linked to dysregulated humoral immune responses in MG. PD-1 appears to play a central role in the pathogenesis of MG, primarily through Tfh cell activity.
