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Article Citation - WoS: 3Citation - Scopus: 3How Do Implant Threads and Diameters Affect the All-On Success? a 3d Finite Element Analysis Study(IOS Press BV, 2022) Zor,Z.F.; Klllnç,Y.; Erkmen,E.; Kurt,A.BACKGROUND: The effect of different thread designs and diameters on the all-on-four concept is unclear. OBJECTIVE: The aim of the study was to clarify the differences in stress distribution of dental implants with various thread designs and diameters based on the all-on-four concept with three dimensional (3D) finite element analysis (FEA). METHODS: A 3D model of a totally edentulous mandible was used to perform the FEA. Four different models (M1, M2, M3, and M4) including 3.5 and 4.3 mm diameter dental implants with active and passive threaded designs were generated. The dental implants were positioned according to the all-on-four concept. The Von Mises stresses on dental implants and maximum and minimum principal stresses (Pmax and Pmin) on bony structures were calculated under vertical, oblique and horizontal loads. RESULTS: For Von Mises stresses, the highest stress values were detected on the distal implants for all models. Distal implants had also the highest stress values for vertical loading. The Von Mises stresses were found to be concentrated around the implant's neck. In all models the highest Pmax and Pmin stresses occurred in the bone surrounding the distal implant. It was noted that the active threaded implants showed the highest Pmax and Pmin stress values. CONCLUSION: The implant thread design and diameter might have a strong influence on the stress values in the all-on-four concept. © 2022 - IOS Press. All rights reserved.Article Toxoplasma gondii Coinfection in HIV-Positive Patients at a Tertiary Care Hospital(Bentham Science Publ Ltd, 2025) Kurkcu, Muhammed Furkan; Bakir, Ayfer; Kaba, Semiha Berra Topsakal; Kusabbi, Ilknur Alkan; Usluca, SelmaIntroduction: Toxoplasma gondii (T. gondii) can cause serious complications in both immunocompetent and immunosuppressed individuals. This study aims to assess the seroprevalence of T. gondii among HIV-positive individuals and to investigate its association with age, sex, CD4+ T cell count, HIV RNA levels, and hematological parameters. Methods: This study included 247 HIV-positive individuals followed up at a tertiary care hospital between November 1, 2022, and November 30, 2024. We analyzed serum samples for T. gondii IgG antibodies using electrochemiluminescent microparticle immunoassay. Results: The prevalence of T. gondii IgG seropositivity was found to be 32.8% (n=81; 95% CI: 26.9-39). The median age of seropositive individuals was 52 years (IQR: 42-61), which was significantly higher compared to seronegative individuals (p<0.001). The highest IgG seropositivity rate (66.7%) was observed in the 61-80 age group. Hemoglobin levels were significantly lower in IgG seropositive individuals (p=0.040). Logistic regression analysis indicated an increased risk of T. gondii infection with advancing age. The odds ratio for the 41-60 age group was 13.3 (95% CI: 1.6-106, p=0.02), while for the 61-80 age group, it was 28 (95% CI: 3.3-240, p=0.002). Discussion: The seroprevalence of T. gondii in HIV-positive individuals was lower than both global and regional averages. Age was identified as an independent risk factor for T. gondii seropositivity. Additionally, hematological alterations associated with anemia were observed in seropositive individuals. Further large-scale, multi-center, and regionally representative studies are required to optimize T. gondii infection management and screening strategies in people living with HIV. Conclusion: These findings suggest that T. gondii infection in HIV-positive individuals increases with age and may be associated with anemia, highlighting the need for age-focused screening and management strategies.Article Investigation of Tetanus Seropositivity Levels in Adult Patients with Rabies Risk Exposure Admitted To a Hospital in Ankara(J Infection Developing Countries, 2025) Gurkaynak, Pinar; Demircan, Serife A.; Tulek, Necla; Kinikli, Sami; Erdinc, Fatma S.; Tuncer, GunayIntroduction: This study aimed to assess tetanus seropositivity levels among adult patients admitted to a tertiary care hospital following rabies risk exposure, and to explore potential factors influencing their immunological status. Methodology: This cross-sectional descriptive epidemiological study included 182 adult individuals (68 females and 114 males) who presented to the hospital following rabies risk exposure. The demographic data was collected during a face-to-face interview, and the tetanus antibody concentrations were assessed using a micro-enzyme-linked immunosorbent assay (ELISA) kit. Serum antibody levels of >= 0.1 IU/mL were defined as "seropositive", while values below this threshold were considered "seronegative". Results: Seropositivity was identified in 81.9% of the patients. There was a significant decline in antibody levels with age (p < 0.001). The Spearman correlation analysis showed a moderately significant negative correlation between age and antibody titers (r = - 0.404, p < 0.001). In addition, there were significantly higher tetanus antibody levels in patients from urban areas, those vaccinated during pregnancy, and those vaccinated within the past 10 years (p = 0.025, 0.036, and 0.013, respectively). Conclusions: Overall, the results highlight a reduction in tetanus antibody levels with age, emphasizing the importance of receiving a booster dose every 10 years. In addition, rabies risk exposure, particularly in older adults, presents a valuable opportunity to administer tetanus vaccination.Article Citation - WoS: 23Citation - Scopus: 25Comparison of Cellular Proliferation on Dense and Porous Pcl Scaffolds(Ios Press, 2008) Sasmazel, Hilal Tuerkoglu; Gumusderelioglu, Menemse; Gurpinar, Aylin; Onur, Mehmet AliIn this contribution, PCL (poly-e caprolactone) scaffolds were prepared by solvent-casting/particle-leaching technique in the presence of two pore formers, PEG(4000) or sucrose molecules in different quantities (0, 10, 20, 30, 40, 50, 55 w/w% PEG(4000)/PCL; 10, 20 w/w% Sucrose/ PCL). The surface and bulk properties of the resulting scaffolds were studied by SEM, DSC and FTIR. SEM photographs showed that, macroporosity was obtained in the PCL structures prepared with sucrose crystals while microporous structure was obtained in the presence of PEG(4000) molecules. Average pore diameters calculated from SEM photographs were 40.1 and 191.2 mu m for 40% PEG(4000)/PCL and 10% Sucrose/PCL scaffolds, respectively. The DSC and FTIR results confirmed that there is no any interaction between pore formers and PCL during structural formation, and both pore formers, PEG(4000) and sucrose, remained independently in the scaffolds. L929 mouse fibroblast cells were seeded onto PCL structures and maintained during 7 days to evaluate cell proliferation. Cell culture results showed that, 10% Sucrose/ PCL scaffold was the most promising substrate for L929 cell growth due to 3-D architecture and macroporous structure of the scaffold.Article Citation - WoS: 3Citation - Scopus: 4Semptomatik Çok Ciddi Aort Darlıklı Hastalarda Transkateter Aort Kapak İmplantasyonun Etkisi(Kare Publ, 2021) Karaduman, Bilge Duran; Ayhan, Hüseyin; Keles, Telat; Bozkurt, EnginAmaç: Aort darlığı (AD) ilerleyici bir hastalıktır ve tek tedavi seçeneği olan kapak replasmanı semptomatik hale geldikten sonra ve geri dönüşümsüz miyokardiyal hasar gelişmeden önce yapılmalıdır. Çok ciddi aort darlığı (ÇCAD) hastalarında cerrahi kapak replasmanı asemptomatik olsa bile önerilmektedir. Ancak ÇCAD hastalarında transkateter aortik kapak implantasyonunun (TAVI) etkisi hakkında ayrıntılı bir çalışma yoktur. Bu çalışmada amacımız, semptomatik ÇCAD hastalarında TAVI’nin uygulanabilirliğini ve güvenilirliğini göstermektir. Yöntemler: Merkezimizde TAVI uygulanan toplam 505 ardışık semptomatik AD hastası retrospektif olarak incelendi. Hastaların ortalama yaşı 77.8±7.6 yıl ve %56.4 kadın idi. Hastalar ÇCAD grubu (n: 134 hasta) ve yüksek gradyentli AD grubu (YGAD, n: 371 hasta) olarak iki gruba ayrıldı. Bulgular: ÇCAD grubunda daha fazla kadın cinsiyet, daha yüksek sol ventrikül ejeksiyon (SV) fraksiyonu, daha fazla küçük SV, hipertrofik SV, daha fazla normal koronerler ve daha az koroner arter hastalığı, bypas cerrahisi, miyokard enfarktüsü ve atriyal fibrilasyon öyküsü vardı. Predilatasyon ve Edwards SAPIEN 3 ÇCAD grubunda olarak daha az kullanıldı. VARC-2 kriterlerine göre majör komplikasyonlar ve hastane içi mortalitede (ÇCAD grubu; 5 hasta, YG AD grubu; 16 hasta, p: 0.769) istatistiksel fark saptanmadı. İki grup arasında Cox regresyon modeli sağ kalım eğrisinde ÇCAD lehine istatistiksel olarak anlamlı fark vardı (p<0.001). Sonuç: Bu çalışmamız ile semptomatik çok ciddi aort darlığında TAVI’nin kabul edilebilir komplikasyon ve daha yüksek sağ kalım oranları ile uygulanabilir ve güvenli olduğu gösterilmiştir. Hâlihazırda cerrahi kapak replasmanı endikasyonu olan asemptomatik ÇCAD hastalarında TAVI uygulanabilmesi için daha fazla randomize büyük çalışma gereklidir.Article Citation - WoS: 1Citation - Scopus: 2Cannabinoid Receptor Ligands Modulate Fibrosis and Inflammation in Idiopathic Pulmonary Fibrosis: a Preliminary Study(Tubitak Scientific & Technological Research Council Turkey, 2024) Kose, Sevil; Onen, Selin; Gizer, Merve; Boduroglu, Esin; Gonullu, Ugur; Korkusuz, PetekBackground/aim: No specific pharmacological treatment regimen for idiopathic pulmonary fibrosis (IPF) exists. Therefore, new antiinflammatory therapeutic strategies are needed. Cannabinoids (CBs), known for their inflammation-modulating and antifibrotic effects, may be potential medication candidates for treating IPF. We aim to evaluate the inflammation-modulating and antifibrotic effects of CB receptor (CBR) agonists and antagonists in lipopolysaccharide-stimulated normal human lung fibroblast, epithelial cells, IPF fibroblast cells, and monocytes. Materials and methods: We detected CBRs in normal human lung fibroblasts (LL24) and IPF fibroblast cells (LL29), epithelial cells (A549) and monocytes (THP-1) by flow cytometry. We determined TGF-(31, IL-8, and TNF-alpha inflammatory cytokines in the LL24, LL29, A549, and THP-1 cell culture supernatants on days 1 and 5 by ELISA. We evaluated the cell viability in LL24, LL29, and A549 cells on days 1, 3, and 5 spectrophotometrically and detected collagen Type I (ColI) production in the LL24 and LL29 cell culture supernatants on days 1, 3, and 5 by ELISA. Results: LL24, LL29, A549, and THP-1 cells exhibited CB1 (CB1R) and CB2 (CB2R) receptors. CB1R and CB2R agonists WIN55,2122 and JWH015 inhibited fibroblastic and epithelial cell proliferation on day 5. TGF-(31 and TNF-alpha release increased, while IL-8 release decreased in LL24, LL29, A549, and THP-1 cells in response to the administration of WIN55,212-2 and JWH015 at a 10-2 mM concentration. CB1R and CB2R antagonists AM251 and AM630 did not block agonistic responses, suggesting a nonclassical CBRmediated pathway. CB2R agonist JWH015 decreased ColI expression in IPF lung fibroblasts LL29 on day 3. Conclusion: These results suggest that CB signaling regulates the progression of pulmonary inflammation and fibrosis via CBR activation. This may offer a potential pharmacological tool for developing antifibrosis therapies.Book Part Citation - WoS: 7Citation - Scopus: 11Magnetic-Based Cell Isolation Technique for the Selection of Stem Cells(Humana Press inc, 2019) Korkusuz, Petek; Kose, Sevil; Yersal, Nilgun; Onen, SelinMagnetic-activated cell sorting (MACS) is the technology that is recently used as a magnetic-based cell isolation/purification technique. This technique enables the isolation and selection of germ, hematopoietic, and somatic stem cells including skin stem cells (SkSCs). Here, we have tried to describe the isolation of stem cells by MACS using CD34 antigen for SkSCs, again CD34 for hematopoietic stem cells (HSCs) and Thy-1 for spermatogonial stem cells (SpSCs). MACS allowed the isolation of CD34+, CD34+, and Thy-1+ human SkSCs, HSCs, and SpSCs with minimum 98% purity.Article Recovery of Myocardial Functions After Kidney Transplantation in Patients With Heart Failure Due To Uremic Cardiomyopathy(Kare Publ, 2025) Ozates, Yelda Saltan; Odabasi, Ahmet Yener; Yildiz, Ufuk; Albayrak, Duygu Genc; Inan, Duygu; Bas, Serap; Tekkesin, Ahmet IlkerObjective: Although left ventricular hypertrophy frequently accompanies end-stage renal disease, heart failure (HF) with reduced ejection fraction (EF) is also observed in a subset of patients. In those patients kidney transplantation (KT) is generally avoided due to an increased risk of mortality in addition to the risks associated with HF. This prospective study was designed to follow patients with HF who were being prepared for KT. Methods: Twenty-five patients with HF due to uremic cardiomyopathy (UC) who had suitable donors (Group 1), 22 patients with HF who could not undergo KT due to a lack of kidney donors (Group 3), and 25 KT candidates with normal ventricular function (Group 2) were included in the study. Left ventricular ejection fraction (LVEF), left atrial diameter (LAD), mitral annular systolic velocity (Sm), left ventricular global longitudinal strain (GLS), and left ventricular mass index (LVMI) values were recorded across four sessions, from pre-transplant to six months post-transplantation. Endomyocardial biopsy was performed for detailed examination of the myocardium in patients in Group 1 and Group 3, and cardiac magnetic resonance imaging (MRI) was performed in all three groups before transplantation. Results: In Group 1, LVEF, Sm, and left ventricular global longitudinal strain (LV-GLS) increased significantly, while LAD and LVMI decreased, all reaching normal levels. In contrast, no changes were observed in Group 3 and Group 2 (P < 0.01 for LVEF, P < 0.01 for GLS, P < 0.01 for LAD, and P < 0.01 for LVMI measurements). No differences in cardiac MRI and biopsy findings were observed between Group 1 and Group 3. Conclusion: Since myocardial function improved significantly and normalized in all patients with it has been demonstrated that UC can be reversible when treated with KT.Article Citation - WoS: 1Citation - Scopus: 1Karotis Arter Stentlemesinin Etkinliği ve Güvenliği: Tek Merkez Deneyimi(Kare Publ, 2020) Karaduman, Bilge Duran; Karaduman, Bilge Duran; Ayhan, Hüseyin; Ayhan, Hüseyin; Keles, Telat; Bozkurt, Engin; Karaduman, Bilge Duran; Ayhan, HüseyinAmaç: İnternal karotis arterdeki orta ve şiddetli darlıklar tüm inmelerin %10–15’ine neden olmaktadır. Bu çalışmada, üçüncü basamak bir referans merkezde karotis arter stentlemesinin (KAS) güvenliğini ve kısa dönem etkinliğini değerlendirmeyi amaçladık. Yöntemler: Üçüncü basamak merkezimizde Ocak 2017 ile Mayıs 2018 arasında KAS uygulanan hastalar geriye dönük olarak değerlendirildi. KAS uygulanan 145 hasta çalışmaya dahil edildi. Bulgular: Hastaların ortalama yaşı 70.1±8.6 yıl idi ve tüm grubun %75.2’si erkek olup %37.9’unda hipertansiyon mevcuttu. Hastaların 81’i (%55.9) semptomatik, 64’ü (%44.1) asemptomatik olarak gruplandırıldı. Semptomatik hastalarda koroner girişimler daha çok KAS sonrası (%38.9) yapılırken, asemptomatik grupta ise KAS öncesi (%25.9) ve sonrasında (%25.9) benzer oranlarda yapıldığı görüldü ama gruplar arasında istatistiksel fark yoktu. Semptomatik hastalarda (%59.2), asemptomatik hastalarda (%78.7) olduğu gibi distal emboli koruyucu cihaz (EKC), proksimal EKC’ye göre daha fazla kullanıldı. Ancak proksimal EKC, semptomatik hastalarda asemptomatik hastalara kıyasla anlamlı olarak daha fazla kullanıldı. Hastane içi ölüm görülmedi ve tüm popülasyonda 5 (%3.4) hastada inme veya geçici iskemik atak (GİA) gözlendi. Asemptomatik grupta GİA veya inme gözlenmedi, semptomatik grupta 2 hastada (%2.4) inme ve 3 hastada (%3.7) GİA görüldü. Sonuç: Bu çalışma kabul edilebilir komplikasyon oranları ile KAS’ın güvenirliğini ve uygulanabilirliğini ortaya koymuştur. KAS prosedürü, deneyimli girişimciler tarafından optimal tıbbi tedavi altında, agresif risk modifikasyonu ile EKC kullanılarak, uygun hastalarda en az komplikasyonla gerçekleştirilmelidir.Review Citation - WoS: 7Citation - Scopus: 8Stereotactic Radiosurgery After Subtotal Resection of Critically-Located Grade I Meningioma: a Single-Center Experience and Review of Literature(Turkish Neurosurgical Soc, 2021) Karaaslan, Burak; Celtikci, Emrah; Bulduk, Erkut Baha; Borcek, Alp Ozgun; Kurt, Gokhan; Kaymaz, Memduh; Emmez, HakanAIM: To analyze the results of stereotactic radiosurgery in 295 patients with residual Grade I meningiomas located at parasellar region, petroclival region, cerebellopontine angle and parasagittal region. MATERIAL and METHODS: A total of 295 patients with Grade 1 residual Meningiomas (197 women, 98 men), who were treated by adjuvant radiosurgery in Gazi University Gamma Knife Center between 2004-2015 were analyzed. WHO Grade 2 and 3 meningiomas were not included in our study. Minimum radiological follow-up was 24 months. The median follow-up was 54 months. The tumor volume, location, treatment dose, morbidity, progression free survival and tumor control rate were analyzed. RESULTS: The median tumor volume was 5.2 cm(3) (0.04-39.7), median age was 50 (20-80), median dose was 14 Gy and tumor control rate was 94.5% (stationary in 85.0%, volume reduction in 9.5%). Increase in tumor volume was seen in 16 patients (5.5%) and re-operation was performed in 5 of them (1.6%). Stereotactic radiosurgery was performed again for 8 patients (2.7%).The location of the tumors was as follows: 39.3% parasellar region, 20% cerebellopontine angle, 13.6% petroclival and 27.1% was parasagittal, falcine or convexity. Major morbidities were detected in 6 (2%) patients. Minor morbidities were detected in 18 (6.1%) patients. CONCLUSION: Stereotactic radiosurgery is an effective and safe treatment modality for residual Grade I meningiomas.
