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Article Does Dexmedetomidine Induce Bone Regeneration in Cranial Defects in Rabbits(Taylor & Francis Ltd, 2025) Erkan, Gozde Nur; Tekin, Umut; Boyacioglu, Ozge; Korkusuz, Petek; Orhan, Kaan; Kirman, Betul; Onder, Mustafa ErcumentDexmedetomidine has been shown to exert protective and curative effects on various tissues and organs in different pathological processes. This study aimed to investigate the effect of dexmedetomidine on the regeneration process after making holes in the parietal bones of rabbits. Twenty-four male Oryctolagus cuniculus rabbits were allocated to three groups, and an 8-mm circular parietal critical-sized bone defect was induced in each animal. Group_C (control) received saline; Group_LD (low dose) was given dexmedetomidine 2.75 mu g/kg; Group_HD (high dose), dexmedetomidine 5.5 mu g/kg; all were administered intraperitoneally for 7 days. After 8 weeks the bones were examined by micro-computed tomography (micro-CT) and histomorphometry. The results indicated that regeneration was improved in both the dexmedetomidine-treated groups. The lower dose increased the bone volume ratio (BV/TV) more than the higher dose. Trabecular thickness, connectivity value, and connectivity density were also higher in Group_LD than in Group_HD. Significant intramembranous ossification was observed in the dexmedetomidine-treated groups, and active osteoblasts were seen at the margins of new bone trabeculae. We conclude that dexmedetomidine, especially at the lower dosage, increases osteoblastic activity and regeneration quality.Article Citation - WoS: 2Citation - Scopus: 2Finite Element Analysis of Stress Distribution on Modified Retentive Tips of Bar Clasp(Taylor & Francis Ltd, 2012) Oyar, P.; Soyarslan, C.; Can, G.; Demirci, E.This study used finite element analysis to evaluate the retentive tips of bar clasps made from different alloys and using different designs in order to determine whether or not different materials and tip forms are suitable for bar clasp applications. Co-Cr, Ti and Type IV Au alloys were selected based on their physical and mechanical properties. The 3D finite element models of three different bar clasp retentive tip geometries prepared from Co-Cr, Ti and Type IV Au alloys were constructed using the finite element software package MSC. Marc. Analysis of a concentrated load of 5N applied to the removable partial denture approach arms in an occlusal direction was performed. Although stress distribution and localisation within bar clasps with different retentive tips were observed to be similar and were concentrated in the approach arm, stress intensities differed in all models.Article Citation - WoS: 10Citation - Scopus: 10Higher Rates of Cefiderocol Resistance Among Ndm Producing klebsiella Bloodstream Isolates Applying Eucast Over Clsi Breakpoints(Taylor & Francis Ltd, 2023) Isler, Burcu; Vatansever, Cansel; Ozer, Berna; Cinar, Gule; Aslan, Abdullah Tarik; Falconer, Caitlin; Harris, Patrick N. A.BackgroundCefiderocol is generally active against carbapenem-resistant Klebsiella spp. (CRK) with higher MICs against metallo-beta-lactamase producers. There is a variation in cefiderocol interpretive criteria determined by EUCAST and CLSI. Our objective was to test CRK isolates against cefiderocol and compare cefiderocol susceptibilities using EUCAST and CLSI interpretive criteria.MethodsA unique collection (n = 254) of mainly OXA-48-like- or NDM-producing CRK bloodstream isolates were tested against cefiderocol with disc diffusion (Mast Diagnostics, UK). Beta-lactam resistance genes and multilocus sequence types were identified using bioinformatics analyses on complete bacterial genomes.ResultsMedian cefiderocol inhibition zone diameter was 24 mm (interquartile range [IQR] 24-26 mm) for all isolates and 18 mm (IQR 15-21 mm) for NDM producers. We observed significant variability between cefiderocol susceptibilities using EUCAST and CLSI breakpoints, such that 26% and 2% of all isolates, and 81% and 12% of the NDM producers were resistant to cefiderocol using EUCAST and CLSI interpretive criteria, respectively.ConclusionsCefiderocol resistance rates among NDM producers are high using EUCAST criteria. Breakpoint variability may have significant implications on patient outcomes. Until more clinical outcome data are available, we suggest using EUCAST interpretive criteria for cefiderocol susceptibility testing.Article Citation - WoS: 2Citation - Scopus: 2Estimation in the Partially Nonlinear Model by Continuous Optimization(Taylor & Francis Ltd, 2021) Yerlikaya-Ozkurt, Fatma; Taylan, Pakize; Tez, MujganA useful model for data analysis is the partially nonlinear model where response variable is represented as the sum of a nonparametric and a parametric component. In this study, we propose a new procedure for estimating the parameters in the partially nonlinear models. Therefore, we consider penalized profile nonlinear least square problem where nonparametric components are expressed as a B-spline basis function, and then estimation problem is expressed in terms of conic quadratic programming which is a continuous optimization problem and solved interior point method. An application study is conducted to evaluate the performance of the proposed method by considering some well-known performance measures. The results are compared against parametric nonlinear model.Article Citation - WoS: 17Citation - Scopus: 17A New Outlier Detection Method Based on Convex Optimization: Application To Diagnosis of Parkinson's Disease(Taylor & Francis Ltd, 2021) Taylan, Pakize; Yerlikaya-Ozkurt, Fatma; Bilgic Ucak, Burcu; Weber, Gerhard-WilhelmNeuroscience is a combination of different scientific disciplines which investigate the nervous system for understanding of the biological basis. Recently, applications to the diagnosis of neurodegenerative diseases like Parkinson's disease have become very promising by considering different statistical regression models. However, well-known statistical regression models may give misleading results for the diagnosis of the neurodegenerative diseases when experimental data contain outlier observations that lie an abnormal distance from the other observation. The main achievements of this study consist of a novel mathematics-supported approach beside statistical regression models to identify and treat the outlier observations without direct elimination for a great and emerging challenge in humankind, such as neurodegenerative diseases. By this approach, a new method named as CMTMSOM is proposed with the contributions of the powerful convex and continuous optimization techniques referred to as conic quadratic programing. This method, based on the mean-shift outlier regression model, is developed by combining robustness of M-estimation and stability of Tikhonov regularization. We apply our method and other parametric models on Parkinson telemonitoring dataset which is a real-world dataset in Neuroscience. Then, we compare these methods by using well-known method-free performance measures. The results indicate that the CMTMSOM method performs better than current parametric models.Article Citation - WoS: 66Citation - Scopus: 89The Potential Medicinal Value of Plants From Asteraceae Family With Antioxidant Defense Enzymes as Biological Targets(Taylor & Francis Ltd, 2015) Koc, Suheda; Isgor, Belgin S.; Isgor, Yasemin G.; Moghaddam, Naznoosh Shomali; Yildirim, OzlemContext: Plants and most of the plant-derived compounds have long been known for their potential pharmaceutical effects. They are well known to play an important role in the treatment of several diseases from diabetes to various types of cancers. Today most of the clinically effective pharmaceuticals are developed from plant-derived ancestors in the history of medicine. Objective: The aim of this study was to evaluate the free radical scavenging activity and total phenolic and flavonoid contents of methanol, ethanol, and acetone extracts from flowers and leaves of Onopordum acanthium L., Carduus acanthoides L., Cirsium arvense (L.) Scop., and Centaurea solstitialis L., all from the Asteraceae family, for investigating their potential medicinal values of biological targets that are participating in the antioxidant defense system such as catalase (CAT), glutathione S-transferase (GST), and glutathione peroxidase (GPx). Materials and methods: In this study, free radical scavenging activity and total phenolic and flavonoid contents of the plant samples were assayed by DPPH, Folin-Ciocalteu, and aluminum chloride colorimetric methods. Also, the effects of extracts on CAT, GST, and GPx enzyme activities were investigated. Results and discussion: The highest phenolic and flavonoid contents were detected in the acetone extract of C. acanthoides flowers, with 90.305 mg GAE/L and 185.43 mg Q/L values, respectively. The highest DPPH radical scavenging was observed with the methanol leaf extracts of C. arvense with an IC50 value of 366 ng/mL. The maximum GPx and GST enzyme inhibition activities were observed with acetone extracts from the flower of C. solstitialis with IC50 values of 79 and 232 ng/mL, respectively.Review Citation - WoS: 8Citation - Scopus: 9Latest Developments in Engineered Skeletal Muscle Tissues for Drug Discovery and Development(Taylor & Francis Ltd, 2023) Ostrovidov, Serge; Ramalingam, Murugan; Bae, Hojae; Orive, Gorka; Fujie, Toshinori; Shi, Xuetao; Kaji, HirokazuIntroductionWith the advances in skeletal muscle tissue engineering, new platforms have arisen with important applications in biology studies, disease modeling, and drug testing. Current developments highlight the quest for engineering skeletal muscle tissues with higher complexity . These new human skeletal muscle tissue models will be powerful tools for drug discovery and development and disease modeling.Areas coveredThe authors review the latest advances in in vitro models of engineered skeletal muscle tissues used for testing drugs with a focus on the use of four main cell culture techniques: Cell cultures in well plates, in microfluidics, in organoids, and in bioprinted constructs. Additional information is provided on the satellite cell niche.Expert opinionIn recent years, more sophisticated in vitro models of skeletal muscle tissues have been fabricated. Important developments have been made in stem cell research and in the engineering of human skeletal muscle tissue. Some platforms have already started to be used for drug testing, notably those based on the parameters of hypertrophy/atrophy and the contractibility of myotubes. More developments are expected through the use of multicellular types and multi-materials as matrices . The validation and use of these models in drug testing should now increase.Article Citation - WoS: 8Citation - Scopus: 10Biomechanical Effects of Two Different Collar Implant Structures on Stress Distribution Under Cantilever Fixed Partial Dentures(Taylor & Francis Ltd, 2011) Meric, Gokce; Erkmen, Erkan; Kurt, Ahmet; Eser, Atilim; Ozden, Ahmet UtkuObjective. The purpose of the study was to compare the effects of two distinct collar geometries of implants on stress distribution in the bone around the implants supporting cantilever fixed partial dentures (CFPDs) as well as in the implant-abutment complex and superstructures. Materials and methods. The three-dimensional finite element method was selected to evaluate the stress distribution. CFPDs which was supported by microthread collar structured (MCS) and non-microthread collar structured (NMCS) implants was modeled; 300 N vertical, 150 N oblique and 60 N horizontal forces were applied to the models separately. The stress values in the bone, implant-abutment complex and superstructures were calculated. Results. In the MCS model, higher stresses were located in the cortical bone and implant-abutment complex in the case of vertical load while decreased stresses in cortical bone and implant-abutment complex were noted within horizontal and oblique loading. In the case of vertical load, decreased stresses have been noted in cancellous bone and framework. Upon horizontal and oblique loading, a MCS model had higher stress in cancellous bone and framework than the NMCS model. Higher von Mises stresses have been noted in veneering material for NMCS models. Conclusion. It has been concluded that stress distribution in implant-supported CFPDs correlated with the macro design of the implant collar and the direction of applied force.Article Citation - WoS: 6Effectiveness of Proprioceptive Neuromuscular Facilitation and Myofascial Release Techniques in Patients With Subacromial Impingement Syndrome(Taylor & Francis Ltd, 2022) Celik, Merve Sinem; Sonmezer, Emel; Acar, ManolyaPurpose To compare the effectiveness of proprioceptive neuromuscular facilitation and myofascial release technique in patients with subacromial impingement syndrome on pain, range of motion, muscle strength, quality of life, functionality and disability. Methods Thirty patients were randomly divided into two groups: proprioceptive neuromuscular facilitation group (n = 15) and proprioceptive neuromuscular facilitation combined with myofascial release technique group (n = 15). Both treatment methods were performed 3 times a week for 4 weeks. Pain severity was assessed by Visuel Analog Scale, range of motion by a goniometer, muscle strength by digital hand dynamometer, quality of life by Nottingham health profile, functionality by arm, shoulder and hand problems questionnaire, disability by shoulder pain and disability index. All measurements were used before and after treatments. Pain severity, range of motion and muscle strength were also evaluated after the first session. Results After the treatment, shoulder pain, range of motion, muscle strength, functionality and disability were improved in two groups (p < 0.05). Proprioceptive neuromuscular facilitation showed improvement in pain, whereas myofascial release technique improved pain, physical activity, emotional state, sleep and total dimensions of life quality (p < 0.05). Proprioceptive neuromuscular facilitation was more effective in reducing activity pain, whereas myofascial release technique was more effective in increasing flexion, external and internal rotation range of motion, flexion and abduction muscle strength after the first session (p < 0.05). Conclusions The combined application of proprioceptive neuromuscular facilitation and myofascial release technique has a more acute and cumulative positive effect on pain, range of motion, muscle strength, functionality, disability and quality of life in patients with subacromial impingement syndrome.Article Citation - WoS: 2Citation - Scopus: 2Cb65 and Novel Cb65 Liposomal System Suppress Mg63 and Saos-2 Osteosarcoma Cell Growth in Vitro(Taylor & Francis Ltd, 2024) Zorba, Basak Isil; Boyacioglu, Oezge; Caglayan, Tugba; Recber, Tuba; Nemutlu, Emirhan; Eroglu, Ipek; Korkusuz, PetekCurable approaches for primary osteosarcoma are inadequate and urge investigation of novel therapeutic formulations. Cannabinoid ligands exert antiproliferative and apoptotic effect on osteosarcoma cells via cannabinoid 2 (CB2) or transient receptor potential vanilloid type (TRPV1) receptors. In this study, we confirmed CB2 receptor expression in MG63 and Saos-2 osteosarcoma cells by qRT-PCR and flow cytometry (FCM), then reported the reduction effect of synthetic specific CB2 receptor agonist CB65 on the proliferation of osteosarcoma cells by WST-1 (water-soluble tetrazolium-1) and RTCA (real-time impedance-based proliferation). CB65 revealed an IC50 (inhibitory concentration) for MG63 and Saos-2 cells as 1.11 x 10(-11) and 4.95 x 10(-11) M, respectively. The specific antiproliferative effect of CB65 on osteosarcoma cells was inhibited by CB2 antagonist AM630. CB65 induced late apoptosis of MG63 and Saos-2 cells at 24 and 48 h, respectively by FCM when applied submaximal concentration. A novel CB65 liposomal system was generated by a thin film hydration method with optimal particle size (141.7 +/- 0.6 nm), polydispersity index (0.451 +/- 0.026), and zeta potential (-10.9 +/- 0.3 mV) values. The encapsulation efficiency (EE%) of the CB65-loaded liposomal formulation was 51.12%. The CB65 and CB65-loaded liposomal formulation releasing IC50 of CB65 reduced proliferation by RTCA and invasion by scratch assay and induced late apoptosis of MG63 and Saos-2 cells, by FCM. Our results demonstrate the CB2 receptor-mediated antiproliferative and apoptotic effect of a new liposomal CB65 delivery system on osteosarcoma cells that can be used as a targeted and intelligent tool for bone tumors to ameliorate pediatric bone cancers following in vivo validation.
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