Publications without Fulltext
Permanent URI for this collectionhttps://hdl.handle.net/20.500.14288/3
Browse
717 results
Filters
Advanced Search
Filter by
Settings
Search Results
Publication Metadata only Anatomical parameters of percutaneous, minimally invasive, direct intralaminar pars screw fixation of spondylolysis(Elsevier Science Inc, 2024) Gudu, Burhan Oral; Aydin, Ahmet Levent; Mercan, Necip Engin; Dilbaz, Suna; Cirak, Musa; N/A; Özer, Ali Fahir; School of Medicine- OBJECTIVE: To investigate the anatomical parameters of the ideal screw trajectory for percutaneous intralaminar screw fixation of a pars defect in lumbar spondylolysis using computed tomography scans. - METHODS: Using advanced radiological software, the ideal intralaminar screw trajectory was determined. The anatomical parameters of this trajectory were analyzed using a total of 80 single-level lumbar tomography scans in patients with spondylolysis at the lumbar 4 vertebrae and lumbar 5 vertebrae levels. The ideal intralaminar screw trajectory started from the inferolateral edge of the lamina and was between the intralaminar region, pars defect, and defective pars neck and pedicle. Along this trajectory, the skin-lamina distance, intralaminar screw length, isthmic lamina length and width, defective pars neck width, lateral entry distance of the screw to the center of the spinous process, and sagittal and coronal screw application angles were analyzed. - RESULTS: When comparing the lumbar 4 vertebrae and lumbar 5 vertebrae parameters, the mean skin-to-lamina distances were 11-9 cm ( P = 0.000), intralaminar screw lengths 3.5-3.6 cm ( P = 0.067), isthmic lamina lengths 22 cm ( P = 0.698), mid-lamina widths 1-1 cm ( P = 0.941), defective pars neck widths 1-1 cm ( P = 0.674), screw lateral entry distances according to the spinous process 1-1.5 cm ( P = 0.000), sagittal screw angles 45 degrees-45 degrees ( P = 0.870), and coronal screw angles 10 degrees-20 degrees ( P = 0.000), respectively. There were no differences based on age and gender ( P < 0.05). - CONCLUSIONS: Percutaneous intralaminar rigid screw fixation of a pars defect in spondylolysis provides minimally invasive, low-profile instrumentation. In spondylolysis, a screw length of 3-4 cm and a screw diameter of 45 mm may be sufficient for pars fixation with intralaminar screws.Publication Metadata only Association of TaqI (rs731236) polymorphism of vitamin D receptor gene with lumbar degenerative disc disease(Elsevier Science Inc, 2024) Serifoglu, Luay; Yilmaz, Seda Gulec; Karaaslanli, Abdulmutalip; Etli, Mustafa Umut; Ozdogan, Selcuk; N/A; Düzkalır, Ali Haluk; N/A; Koç University Hospital- BACKGROUND: Lumbar degenerative disc disease (LDDD) significantly contributes to low back pain, with a complicated etiology involving genetic and environmental facts. The aim of study was to investigate the association between the Taq I (rs731236) polymorphism of the vitamin D receptor ( VDR ) gene with LDDD. - METHODS: In total, 248 patients with symptomatic LDDD and 146 control subjects were examined. The evaluation of clinical features of patients with LDDD comprised radiodiagnostic magnetic resonance imaging, neurologic examinations, pain scores including the visual analog scale (VAS), and disability investigation with Oswestry Disability Index (ODI). Genotyping of the VDR gene polymorphism was conducted using polymerase chain reaction ebased methods.- RESULTS: Individuals of the LDDD group who were VDR TaqI AA genotype carriers were significantly greater than the other group ( P = 0.014), whereas those with GG genotype were significantly lower ( P = 0.028) in the patient group. In addition, VAS and ODI scores were significantly lower in the GG genotype carrier group, whereas AA genotype carriers had the greatest scores ( P = 0.004). Carrying the G allele decreased the risk of LDDD 1.7 times ( P = 0.014) and carrying the A allele enhanced the risk 1.8 times ( P = 0.028). Moreover, G-allele carriers had significantly lower VAS ( P = 0.002) and ODI scores ( P < 0.0001). - CONCLUSIONS: VDR Taq I (rs731236) GG genotype and G allele have protective potential, whereas the AA genotype and A allele are risk factors for LDDD. The findings reveal a statistically significant association of the Taq I (rs731236) polymorphism of VDR gene polymorphism with LDDD. This result highlights the potential role of genetic factors in developing LDDD and suggests avenues for future research in genetic screening and personalized treatment strategies.Publication Metadata only The relationship between inflammatory processes and apoptosis in lumbar disc degeneration(Elsevier Inc., 2024) Cetintas, Semih Can; Akyol, Sibel; Alizada, Orkhan; Tahmazoglu, Burak; Hanci, Murat; Isler, Cihan; N/A; Akgün, Mehmet Yiğit; N/A; Koç University HospitalObjective: Degenerative Disc Disease (DDD) is a common health problem in the population. There are recent studies focusing on relationship between DDD and immunological factors. However, there is still a lack of data on the role of apoptosis in DDD pathophysiology. Therefore, we aimed to investigate the relationship between Modic-type changes and the apoptosis in DDD. Materials and Methods: Ninety adult male patients who presented with low back and/or radicular pain and were operated on due to lumbar disc herniation were included. Three groups were formed based on Modic type degeneration observed on magnetic resonance imaging. Specific parameters involved in the intrinsic and extrinsic pathways of apoptosis were assessed in excised disc materials using the enzyme-linked immunosorbent assay method. Results: All three groups formed according to Modic degeneration types were homogenous in all variances. Cytochrome-C was significantly decreased only in the Modic type-3 group, whereas Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand Receptor-1, B-Cell Lymphoma-2 (Bcl-2) Homologous Antagonist Killer-1, Direct Inhibitor of Apoptosis-Binding Protein with Low Pi, and Bcl-2 Associated X Apoptosis Regulator levels were significantly different in both Modic type-2 and -3 groups. However, BH3 interacting domain death agonist and Bcl-2 levels were similar across all groups. Conclusions: In conclusion, this study suggests that Direct Inhibitor of Apoptosis-Binding Protein with Low Pi, cytochrome - c, Bcl-2 Associated X Apoptosis Regulator, Bcl-2 Homologous Antagonist Killer-1, and Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand Receptor-1proteins play important roles in the development and progression of DDD and are correlated with Modic types. Further studies are needed to explore the potential therapeutic role of inhibiting these apoptotic proteins in DDD. © 2024 Elsevier Inc.Publication Metadata only Comparative transcriptomic analyses of peripheral blood mononuclear cells of Covid-19 patients without pneumonia and with severe pneumonia in the first year of follow-up(Multidisciplinary Digital Publishing Institute (MDPI), 2024) Cetinkaya, Pelin Duru; Eldem, Vaha; Argun Baris, Serap; Kokturk, Nurda; Kuralay, Selim Can; Pinar Deniz, Pelin; Baydar Toprak, Oya; Yildiz Gulhan, Pinar; Sagcan, Gulseren; Kose, Neslihan; Tomruk Erdem, Aysegul; Fakili, Fusun; Ozturk, Onder; Basyigit, Ilknur; Boyaci, Hasim; Azak, Emel; Ulukavak Ciftci, Tansu; Oguzulgen, Ipek Kivilcim; Ozger, Hasan Selcuk; Aysert Yildiz, Pinar; Hanta, Ismail; Ataoglu, Ozlem; Ercelik, Merve; Cuhadaroglu, Caglar; Okur, Hacer Kuzu; Tor, Muge Meltem; Nurlu Temel, Esra; Kul, Seval; Itil, Oya; N/A; Kayalar, Özgecan; Rajabi, Hadi; Konyalılar, Nur; Mortazavi, Deniz; Korkunç, Seval Kübra; Erkan, Sinem; Aksoy, Gizem Tuşe; Eyikudamacı, Gül; Tütüncü, Yıldız; Bayram, Hasan; Koç University Research Center for Translational Medicine (KUTTAM); Graduate School of Health Sciences; Graduate School of Sciences and Engineering; School of MedicineThe multisystemic effects of COVID-19 may continue for a longer time period following the acute phase, depending on the severity of the disease. However, long-term systemic transcriptomic changes associated with COVID-19 disease and the impact of disease severity are not fully understood. We aimed to investigate the impact of COVID-19 and its severity on transcriptomic alterations in peripheral blood mononuclear cells (PBMCs) following 1 year of the disease. PBMCs were isolated from the peripheral blood of healthy control donors who did not have COVID-19 (C; n = 13), from COVID-19 patients without pneumonia (NP; n = 11), and from COVID-19 patients with severe pneumonia (SP; n = 10) after 1-year of follow-up. Following RNA isolation from PBMCs, high-quality RNAs were sequenced after creating a library. Differentially expressed genes (DEGs) and differentially expressed long non-coding RNAs (DElncRNAs) were identified using Benjamini–Hochberg correction and they were analysed for hierarchical clustering and principal component analysis (PCA). Intergroup comparisons (C vs. NP, C vs. SP, and NP vs. SP) of DEGs and DElncRNAs were performed and hub genes were determined. Functional enrichment analyses of DEGs and DElncRNAs were made using Metascape (v3.5.20240101) and the first version of NCPATH. The RNA sequencing analysis revealed 4843 DEGs and 1056 DElncRNAs in “C vs. NP”, 1651 DEGs and 577 DElncRNAs in “C vs. SP”, and 954 DEGs and 148 DElncRNAs in “NP vs. SP”, with 291 DEGs and 70 DElncRNAs shared across all groups, respectively. We identified 14 hub genes from 291 DEGs, with functional enrichment analysis showing upregulated DEGs mainly linked to inflammation and osteoclast differentiation and downregulated DEGs to viral infections and immune responses. The analysis showed that 291 common and 14 hub genes were associated with pneumonia and that these genes could be regulated by the transcription factors JUN and NFκB1 carrying the NFκB binding site. We also revealed unique immune cell signatures across DEG categories indicating that the upregulated DEGs were associated with neutrophils and monocytes, while downregulated DEGs were associated with CD4 memory effector T cells. The comparative transcriptomic analysis of NP and SP groups with 52 gene signatures suggestive of IPF risk showed a lower risk of IPF in the SP group than the NP patients. Our findings suggest that COVID-19 may cause long term pathologies by modulating the expression of various DEGs, DeLncRNAs, and hub genes at the cellular level. © 2024 by the authors.Publication Metadata only The role of neoadjuvant chemotherapy for patients with variant histology muscle invasive bladder cancer undergoing robotic cystectomy: data from the International Robotic Cystectomy Consortium(Elsevier Inc., 2024) Cooke, Ian; Abou Heidar, Nassib; Mahmood, Abdul Wasay; Ahmad, Ali; Jing, Zhe; Stöckle, Michael; Wagner, Andrew A; Roupret, Morgan; Kim, Eric; Vasdev, Nikhil; Rha, Koon Ho; Aboumohamed, Ahmed; Dasgupta, Prokar; Maatman, Thomas J.; Richstone, Lee; Wiklund, Peter; Gaboardi, Franco; Li, Qiang; Hussein, Ahmed A.; Guru, Khurshid; N/A; Balbay, Mevlana Derya; School of MedicineObjective: To assess the role of neoadjuvant chemotherapy (NAC) before robot-assisted radical cystectomy (RARC) for patients with variant histology (VH) muscle-invasive bladder cancer (MIBC). Methods: Retrospective review of 988 patients who underwent RARC (2004–2023) for MIBC. Primary outcomes included the utilization of NAC among this cohort of patients, frequency of downstaging, and discordance between preoperative and final pathology in terms of the presence of VH. Secondary outcomes included disease-specific (DSS), recurrence-free (RFS), and overall survival (OS). Results: A total of 349 (35%) had VH on transurethral resection or at RARC. The 4 most common VH subgroups were squamous (n = 94), adenocarcinoma (n = 64), micropapillary (n = 34), and sarcomatoid (n = 21). There was no difference in OS (log-rank: P = 0.43 for adenocarcinoma, P = 0.12 for micropapillary, P = 0.55 for sarcomatoid, P = 0.29 for squamous), RFS (log-rank: P = 0.25 for adenocarcinoma, P = 0.35 for micropapillary, P = 0.83 for sarcomatoid, P = 0.79 for squamous), or DSS (log-rank P = 0.91 for adenocarcinoma, P = 0.15 for micropapillary, 0.28 for sarcomatoid, P = 0.92 for squamous) among any of the VH based on receipt of NAC. Patients with squamous histology who received NAC were more likely to be downstaged on final pathology compared to those who did not (P < 0.01). Conclusion: Our data showed no significant difference in OS, RFS, or DSS for patients with VH MIBC cancer who received NAC before RARC. Patients with the squamous variant who received NAC had more pathologic downstaging compared to those who did not. The role of NAC among patients with VH is yet to be defined. Results were limited by small number in each individual group and lack of exact proportion of VH. © 2024Publication Metadata only Multicentric evaluation of high and low power lasers on RIRS success using propensity score analysis(Springer, 2024) Erol, Eren; Ecer, Gokhan; Gokce, Mehmet Ilker; Balasar, Mehmet; Babayigit, Muammer; Aksoy, Elif Ipek; Sarica, Kemal; Ahmed, Kamran; Guven, Selcuk; N/A; Kiremit, Murat Can; Sarıkaya, Ahmet Furkan; Karaarslan, Umut Can; School of MedicineIn this study, we aimed to evaluate the effect of HPL on different parameters by different centers and urologists. While doing this, we evaluated different parameters by comparing HPL(High Power laser) and LPL(Low-power laser). This is an observational, retrospective, comparative, multicentric study of prospectively organised database. A total of 217 patients who underwent RIRS for kidney stones smaller than 2 cm in three different centers were included in the study. The patients were divided into two groups; LPL used (Group1, n:121 patients) and HPL used (Group2, n:96). Propensity score matching was done in the data analysis part. After matching, a total of 192 patients, 96 patients in both groups, were evaluated. There was no difference between the groups regarding age, gender, stone side, and stone location. The stone-free rate on the first day was 80.3% in Group 1, it was 78.1% in Group 2 (p = 0.9). In the third month, it was 90.7% in Group 1 and 87.5% in Group 2 (p:0.7).Hospitalization duration was significantly higher in Group 1. (2.35 +/- 2.27 days vs. 1.42 +/- 1.10 days; p < 0.001).The operation duration was 88.70 +/- 29.72 min in Group1 and 66.17 +/- 41.02 min in Group2 (p < 0.001). The fluoroscopy time (FT) was 90.73 +/- 4.79 s in Group 1 and 50.78 +/- 5.64 s in Group 2 (p < 0.001). Complications according to Clavien Classification, were similar between the groups(p > 0.05). According to our study similar SFR and complication rates were found with HPL and LPL. In addition, patients who used HPL had lower operation time, hospital stay, and fluoroscopy time than the LPL group. Although high-power lasers are expensive in terms of cost, they affect many parameters and strengthen the hand of urologists thanks to the wide energy and frequency range they offer.Publication Metadata only The effect of endoscopic renal and ureteral stone surgeries on renal blood flow in children: a prospective trial(Springer, 2024) Topbas, Fevzi Batuhan; Sekerci, Cagri Akin; Soydemir, Efe; Yapici, Ozge; Akbas, Serkan; Yucel, Selcuk; Tanidir, Yiloren; N/A; Tarcan, Tufan; School of MedicineAim: To assess the impact of endoscopic stone surgeries on renal perfusion and blood flow in children. Materials and methods: Children who underwent percutaneous nephrolithotomy (PCNL), retrograde intrarenal surgery (RIRS), ureterorenoscopy (URS), endoscopic combined intrarenal surgery (ECIRS) were included to the study. Renal Doppler ultrasonography (RDUS) was performed one day before the operation, and on the postoperative 1st day and 1st month. Peak systolic velocity (PSV) and end-diastolic velocity (EDV) were measured, and resistive index (RI) was calculated with the (PSV-EDV)/PSV formula. RDUS parameters were compared before and after surgery and between ipsilateral and contralateral kidneys. Results: A total of 45 children with a median age was 8 (2-17) years were included (15 (33.3%) girls, 30 (66.7%) boys). PCNL was performed in 13 children (28.9%), RIRS 11 (24.4%), URS 12 (26.7%), and ECIRS 9 (20%). There was no significant difference in renal and segmental PSV, EDV and RI values of operated kidney in the preoperative, postoperative periods. There was no significant difference between RDUS parameters of the ipsilateral and contralateral kidneys in preoperative or postoperative periods. PSV and EDV values were significantly higher in the 1st postoperative month in the group without preoperative DJ stent than in the group with DJ stent (p = 0,031, p = 0,041, respectively). However, RI values were similar. The mean RI were below the threshold value of 0.7 in each period. Conclusion: RDUS parameters didn't show a significant difference in children. Endoscopic surgeries can be safely performed in pediatric stone disease.Publication Metadata only Prognostic significance of lymph node count in surgically treated patients with T2-4 stage nonmetastatic adrenocortical carcinoma(Elsevier Inc., 2024) Assad, Anis; Barletta, Francesco; Incesu, Reha-Baris; Scheipner, Lukas; Morra, Simone; Baudo, Andrea; Garcia, Cristina Cano; Tian, Zhe; Ahyai, Sascha; Longo, Nicola; Chun, Felix K.H.; Shariat, Shahrokh F.; Briganti, Alberto; Saad, Fred; Karakiewicz, Pierre I.; N/A; Tilki, Derya; School of MedicinePurpose: The role of lymphadenectomy and the optimal lymph node count (LNC) cut-off in nonmetastatic adrenocortical carcinoma (nmACC) are unclear. Methods: Within the Surveillance, Epidemiology, and End Results (SEER) database, surgically treated nmACC patients with T2-4 stages were identified between 2004 and 2020. We tested for cancer-specific mortality (CSM) differences according to pathological N-stage (pN0 vs. pN1) and two previously recommended LNC cut-offs (≥4 vs. ≥5) were tested in pN0 and subsequently in pN1 subgroups in Kaplan-Meier plots and multivariable Cox regression models. Results: Of 710 surgically treated nmACC patients, 185 (26%) underwent lymphadenectomy and were assessable for further analyses based on available LNC data. Of 185 assessable patients, 152 (82%) were pN0 and 33 (18%) were pN1. In Kaplan-Meier analyses, CSM-free survival was 74 vs. 14 months (Δ 60 months, P ≤ 0.001) in pN0 vs. pN1 patients, respectively. In multivariable analyses, pN1 was an independent predictor of higher CSM (HR:3.13, P < 0.001). In sensitivity analyses addressing pN0, LNC cut-off of ≥4 was associated with lower CSM (multivariable hazard ratio [HR]: 0.52; P = 0.002). In sensitivity analyses addressing pN0, no difference was recorded when a LNC cut-off of ≥5 was used (HR:0.60, P = 0.09). In pN1 patients, neither of the cut-offs (≥4 and ≥5) resulted in a statistically significant stratification of CSM rate, and neither reached independent predictor status (all P > 0.05). Conclusions: Lymphadenectomy provides a prognostic benefit in nmACC patients and identifies pN1 patients with dismal prognosis. Conversely, in pN0 patients, a LNC cut-off ≥4 identifies those with particularly favorable prognosis. © 2024 Elsevier Inc.Publication Metadata only Clinical, radiological, and surgical outcomes of 431 patients with adrenal incidentalomas: retrospective study of a 10-year single-center experience(Tubitak Scientific & Technological Research Council Turkey, 2024) Imga, Narin Nasiroglu; Aslan, Yilmaz; Catak, Merve; Tuncel, Altug; Berker, Dilek; N/A; Aykanat, İbrahim Can; N/A; Koç University HospitalBackground/aim: The incidence of adrenal tumors is increasing due to the widespread utilization of radiographic imaging techniques. Factors such as tumor size, radiological characteristics, and functionality of adrenal adenomas play crucial roles in diagnosis and subsequent management. In this retrospective study, we investigated the clinical, radiological, and surgical features of patients with adrenal incidentalomas (AIs) and evaluated their follow-up results. Materials and methods: We analyzed data from 431 patients diagnosed with AIs (130 males, 301 females) who underwent adrenal hormone evaluation at our center. We compared nonfunctioning and functioning AIs in terms of radiological features. We also compared baseline and follow-up characteristics in nonfunctioning AIs. Results: The mean age of the patients was 55.4 +/- 11.5 years, with a mean tumor size of 25.9 +/- 14.3 mm. Mean follow-up duration was 3.17 +/- 2.07 years. Adenoma localization revealed 165 (38.3%) right-sided, 185 (42.9%) left-sided, and 81 (18.8%) bilateral cases. Most patients (76.6%) had nonfunctioning AIs. During follow-up, nonfunctioning AIs exhibited increased fasting blood glucose, fasting insulin and HOMA-IR values (p = 0.002, <0.001 and 0.004, respectively). Among the functioning AIs cases (23.4%), autonomous cortisol secretion, Cushing's syndrome, pheochromocytoma, and primary aldosteronism were observed in 10.4%, 5.1%, 3.9%, and 3.9% of cases, respectively. Receiver operating characteristic curve analysis determined an adrenal adenoma size of 26.5 mm as the optimal cut-off for distinguishing between functioning and nonfunctioning AIs, with a sensitivity and specificity of 61.4% and 70.0%, respectively. Conclusion: Although the majority of AIs are nonfunctioning, the prevalence of functioning adrenal adenomas is not rare. Our findings suggest that adenoma size emerges as a valuable predictor for early detection of functioning adenomas. In addition, smaller masses appear to carry a lower risk of malignancy.Publication Metadata only The use of pre-chemoradiotherapy total masseter muscle volume as a novel predictor of radiation-induced trismus in locally advanced nasopharyngeal carcinoma patients(MDPI, 2024) Somay, Efsun; Topkan, Erkan; Pehlivan, Umur Anil; Yilmaz, Busra; Besen, Ali Ayberk; Mertsoylu, Huseyin; Pehlivan, Berrin; N/A; Selek, Uğur; School of MedicineBackground: We sought to determine whether pretreatment total masseter muscle volume (TMMV) measures can predict radiation-induced trismus (RIT) in patients with locally advanced nasopharyngeal carcinoma (LA-NPC) receiving concurrent chemoradiotherapy (C-CRT). Methods: We retrospectively reviewed the medical records of LA-NPC patients who received C-CRT and had pretreatment maximum mouth openings (MMO) greater than 35 mm. MMO of 35 mm or less after C-CRT were considered RIT. We employed receiver operating characteristic (ROC) curve analysis to explore the correlation between pre-treatment TMMV readings and RIT status. Results: Out of the 112 eligible patients, 22.0% of them received a diagnosis of RIT after C-CRT. The optimal TMMV cutoff that was significantly linked to post-C-CRT RIT rates was determined to be 35.0 cc [area under the curve: 79.5%; sensitivity: 75.0%; and specificity: 78.6%; Youden index: 0.536] in the ROC curve analysis. The incidence of RIT was significantly higher in patients with TMMV <= 5.0 cc than in those with TMMV > 35.0 cc [51.2% vs. 8.7%; Odds ratio: 6.79; p < 0.001]. A multivariate logistic regression analysis revealed that pre-C-CRT MMO <= 41.6 mm (p = 0.001), mean masticatory apparatus dose V56.5 >= 34% group (p = 0.002), and TMMV <= 35 cc were the independent predictors of significantly elevated rates of RIT. Conclusion: The presence of a smaller pretreatment TMMV is a reliable and independent novel biological marker that can confidently predict higher RIT rates in LA-NPC patients who receive C-CRT.