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Öğe Curcumin-loaded emulsome nanoparticles induces apoptosis through p53 signaling pathway in pancreatic cancer cell line panc-1(2025) Demirci, Züleyha; İşlek, Zeynep; Sığınç, Halime İlhan; Şahin, Fikrettin; Üçışık, Mehmet Hikmet; Bolat, Zeynep BüşraPancreatic cancer is a global health problem with a poor prognosis, limited treatment options and low survival rates of patients. Thus, the exploration of novel treatment approaches is crucial. Curcumin shows promise in pancreatic cancer. Curcumin has anticancer properties promoting apoptosis through the p53 pathway. However, adverse effects and low bioavailability are curcumin's main drawbacks and its delivery by nanoparticles could improve its effectiveness as a treatment option. Curcumin-loaded emulsome nanoparticles (CurEm) have shown promise in colorectal, hepatocellular, and prostate cancers. This study aims to evaluate the anticancer potential of CurEm in pancreatic cancer cell line PANC-1. The cytotoxic effects of CurEm on PANC-1 cells show cytotoxicity in dose and time-dependent manner. The selected dose 30 μM CurEm resulted spheroidal morphology in PANC-1 cells and colony forming and scratch assay conducted demonstrated significant growth inhibition and decrease in migration ability, respectively. Cell cycle analysis shows that CurEm induces G2/M arrest in PANC-1 cells. CurEm-treated PANC-1 cells showed a significant increase in p53 and Caspase 3 genes, while a significant decrease in Bcl-2 genes compared to untreated group. Western blot results showed parallel results to qPCR analysis for Bcl-2 protein levels. Interestingly, we saw low p53 protein levels in CurEm-treated PANC-1 cells. These findings shed light on the potential of CurEm as an effective and stable therapeutic approach for pancreatic cancer.Öğe Efficacy and safety of sulforaphane-loaded emulsomes as tested on MCF7 and MCF10A cells(2024) Karroum, Reem; Üçışık, Mehmet HikmetObjectives: Sulforaphane is well-known for its anti-cancer properties particularly against breast, skin and prostate cancers. High sensitivity of sulforaphane to oxygen, heat, and alkaline conditions, as well as its poor oral bioavailability and water instability limit its use in medicine. In this study, we aim to overcome the prementioned limitations by encapsulating sulforaphane within a lipid-based drug delivery system, known as emulsome, and investigate the anti-cancer features of the attained formulation. Methods: The stability and dispersity of the formulation were assessed sequentially by zeta sizer, scanning electron microscopy and confocal laser scanning microscopy. Cell culture studies were performed to evaluate the anticancer activity of the formulation. Results: Sulforaphane-loaded emulsomes with an average particle size of 246.0±14.1 nm, an average zeta potential of −23.5±2.4 mV and a polydispersity index of around 0.38 were produced. Encapsulations up to 0.036 mg/mL sulforaphane concentration was achieved. When MCF7 breast cancer cells were treated with sulforaphane-loaded emulsomes, a significant decrease was observed in proliferation of the cells along 72 h. In control group, emulsomes were found safe as tested at same concentrations on MCF-10a healthy cells. Applied as dissolved in DMSO, free sulforaphane with an IC50 value of 1.2 µM was more effective against MCF7 cells than sulforaphane-loaded emulsome formulation having a IC50 value 21.1 µM. Conclusions: Sulforaphane-loaded emulsomes were obtained as stable, moderately disperse suspensions. Delivery of the bioactive compound into the cells were achieved. Yet, its biological activity remained behind its free form.Öğe Experimental design and characterization of dual-antibody-conjugated all-trans retinoic acid-loaded lipid nanoparticles as a potential cancer therapy(2024) İşlek, Zeynep; Sağıroğlu, Ali Asram; Üçışık, Mehmet Hikmet; Kırbaş, Oğuz Kaan; Demirel, Erhan; Yurdasiper, Aysu; Şahin, Fikrettin; Özer, ÖzgenAntibody-targeted immunotherapy has emerged in cancer therapies regarding checkpoint inhibition with monoclonal antibodies, such as anti-programmed death-ligand 1 (anti-PD-L1) either given alone or in combination. However, when given alone, it may fail to activate tumor-specific T cells. The combinational therapy of anti-PD-L1 with anti-4-1BB and all-trans retinoic acid (ATRA) has come into prominence due to disease heterogeneity, resulting in the synergistic effects associated with greater T-cell responses. This study introduces anti-PD-L1 and anti-4-1BB-conjugated ATRA-loaded solid lipid nanoparticles (SLNs), where the Design-Expert Program was applied for the optimization. Accordingly, antibody–conjugated ATRA-loaded SLNs had uniform dispersions with mean diameters of 179.6 ± 12.6 nm. The formulations achieved the encapsulation efficiency (EE %) of ATRA at 21.2 ± 1.4 %, regarding the three-dimensional response surface graph. The binding efficiency of anti-4-1BB and anti-PD-L1 antibodies were determined as 85.59 ± 7.3 % and 90.02 ± 5.4 %, respectively. The release profile of formulations indicated the biphasic release of ATRA (ie., 76 ± 4.4 %) from SLNs within 24 h via the Higuchi model. Particle size distributions of SLNs displayed a 7 % increase (i.e., 190.5 ± 7.63 nm) at 4 °C over 2 months. The experimental design of anti-PD-L1- and anti-4-1BB-conjugated- ATRA-loaded SLNs highlighted the promising strategy for the development of alternative formulations and the potential approach for further cancer therapies.Öğe Residues in the fructose-binding pocket are required for ketohexokinase-A activity(2024) Ferreira, Juliana C.; Villanueva, Adrian J.; Fadl, Samar; Al Adem, Kenana; Cinviz, Zeynep Nur; Nedyalkova, Lyudmila; Cardoso, Thyago H.S.; Andrade, Mario Edson; Saksena, Nitin K.; Şensoy, Özge; Rabeh, Wael M.Excessive fructose consumption is a primary contributor to the global surges in obesity, cancer, and metabolic syndrome. Fructolysis is not robustly regulated and is initiated by ketohexokinase (KHK). In this study, we determined the crystal structure of KHK-A, one of two human isozymes of KHK, in the apo-state at 1.85 Å resolution, and we investigated the roles of residues in the fructose-binding pocket by mutational analysis. Introducing alanine at D15, N42, or N45 inactivated KHK-A, whereas mutating R141 or K174 reduced activity and thermodynamic stability. Kinetic studies revealed that the R141A and K174A mutations reduced fructose affinity by 2- to 4-fold compared to WT KHK-A, without affecting ATP affinity. Molecular dynamics simulations provided mechanistic insights into the potential roles of the mutated residues in ligand coordination and the maintenance of an open state in one monomer and a closed state in the other. Protein–protein interactome analysis indicated distinct expression patterns and downregulation of partner proteins in different tumor tissues, warranting a reevaluation of KHK's role in cancer development and progression. The connections between different cancer genes and the KHK signaling pathway suggest that KHK is a potential target for preventing cancer metastasis. This study enhances our understanding of KHK-A's structure and function and offers valuable insights into potential targets for developing treatments for obesity, cancer, and metabolic syndrome.Öğe Nanoparticle-mediated histotripsy using dual-frequency pulsing methods(2024) Edsall, Connor; Huynh, Laura; Mustafa, Waleed; Hall, Timothy L.; Yüksel Durmaz, Yasemin; Vlaisavljevich, EliObjective: Nanoparticle-mediated histotripsy (NMH) is a novel ablation method that combines nanoparticles as artificial cavitation nuclei with focused ultrasound pulsing to achieve targeted, non-invasive, and cell-selective tumor ablation. The study described here examined the effect of dual-frequency histotripsy pulsing on the cavitation threshold, bubble cloud characteristics, and ablative efficiency in NMH. High-speed optical imaging was used to analyze bubble cloud characteristics and to measure ablation efficiency for NMH inside agarose tissue phantoms containing perfluorohexane-filled nanocone clusters, which were previously developed to reduce the histotripsy cavitation threshold for NMH. Methods: Dual-frequency histotripsy pulsing was applied at a 1:1 pressure ratio using a modular 500 kHz and 3 MHz dual-frequency array transducer. Optical imaging results revealed predictable, well-defined bubble clouds generated for all tested cases with similar reductions in the cavitation thresholds observed for single-frequency and dual-frequency pulsing. Results: Dual-frequency pulsing was seen to nucleate small, dense clouds in agarose phantoms, intermediate in size of their component frequencies but closer in area to that of the higher component frequency. Red blood cell experiments revealed complete ablations were generated by dual-frequency NMH in all phantoms in <1500 pulses. This result was a significant increase in ablation efficiency compared with the ?4000 pulses required in prior single-frequency NMH studies. Conclusion: Overall, this study indicates the potential for using dual-frequency histotripsy methods to increase the ablation efficacy of NMH.Öğe The effect of PEGylation components on drug release behavior of targeted reduced graphene oxide based drug delivery system(2024) Başavcı, Ezgi; Demirel, Erhan; Elhassan, Mohamad; Yüksel Durmaz, YaseminReduced graphene oxide (rGO) is a restored, defect-free version of graphene oxide (GO) with regained graphene-like properties but encounters challenges in biomedical applications due to its low solubility. Especially for drug release applications, rGO's stronger ?-? interaction of rGO compared to GO leads to low release, often demanding novel approaches for enhancement. The recently developed PEGylation method utilizes a copolymer with tunable PEG chain length and density for the PEGylation of GO simultaneously reduced to rGO, resulting in water-dispersible and biocompatible rGO-based nanoplatforms. This copolymer integrates functional monomers and enhances treatment options. Herein, we investigated how these PEGylation components and their incorporation order impact rGO's drug release behavior. A series of copolymers, (P(PEGMA-co-AzPMA-co-MMA-co-PMA), with different PEG brushes and azide groups, were synthesized via atom transfer radical polymerization. We explored the impact of ionic azide groups on drug release by comparing the azide-containing and azide-capped copolymers. Moreover, copolymers containing 500 or 2000 Da PEG brushes were compared to assess their role as a coating layer or diffusion barrier on drug release. Doxorubicin, a hydrophobic anticancer agent, was loaded onto the rGO surface before or after peptide-based targeting agent (EPPT1) conjugation. The results showed that the drug release behavior of 500 or 2000 Da PEG brushes containing rGO surfaces are different due to the density of PEG coating which makes the effect of azide groups not always visible. Incorporating the targeting peptide before drug loading was found to be optimal. The pH-dependent release profiles revealed 49 % and 44 % release from the rGO surface for the shorter and longer PEG brushes, respectively. Tuning the PEGylation components may further influence the release behavior.Öğe Effects of bone surface topography and chemistry on macrophage polarization(2024) Özçolak, Birgün; Erenay, Berkay; Odabaş, Sedat; Jandt, Klaus D.; Garipcan, BoraSurface structure plays a crucial role in determining cell behavior on biomaterials, influencing cell adhesion, proliferation, differentiation, as well as immune cells and macrophage polarization. While grooves and ridges stimulate M2 polarization and pits and bumps promote M1 polarization, these structures do not accurately mimic the real bone surface. Consequently, the impact of mimicking bone surface topography on macrophage polarization remains unknown. Understanding the synergistic sequential roles of M1 and M2 macrophages in osteoimmunomodulation is crucial for effective bone tissue engineering. Thus, exploring the impact of bone surface microstructure mimicking biomaterials on macrophage polarization is critical. In this study, we aimed to sequentially activate M1 and M2 macrophages using Poly-L-Lactic acid (PLA) membranes with bone surface topographical features mimicked through the soft lithography technique. To mimic the bone surface topography, a bovine femur was used as a model surface, and the membranes were further modified with collagen type-I and hydroxyapatite to mimic the bone surface microenvironment. To determine the effect of these biomaterials on macrophage polarization, we conducted experimental analysis that contained estimating cytokine release profiles and characterizing cell morphology. Our results demonstrated the potential of the hydroxyapatite-deposited bone surface-mimicked PLA membranes to trigger sequential and synergistic M1 and M2 macrophage polarizations, suggesting their ability to achieve osteoimmunomodulatory macrophage polarization for bone tissue engineering applications. Although further experimental studies are required to completely investigate the osteoimmunomodulatory effects of these biomaterials, our results provide valuable insights into the potential advantages of biomaterials that mimic the complex microenvironment of bone surfaces.Öğe Effect of a pedicle screw fixation system on lumbar spinal segments: A finite element study(2023) Akıncı, Saliha Zeyneb; Karabulut, Derya; Doğru, Suzan Cansel; Sürmen, Hasan Kemal; Yaman, Onur; Arslan, Yunus ZiyaObjective: Spinal implants have been used to stimulate fusion by surgical adjustment and correct abnormal alignment of the vertebral column. Spinal fusion can cause some spinal disorders and hence describing the changes in biomechanical forces would help to understand these complications. In this study, we used two lumbar mod-els. One of them is used without the fixed pedicle screw system, and the other one was used with that system. Therefore, we aimed to investigate the biomechanical effect of a pedicle screw fixation system on the lumbar functional spinal unit under applied forces. Material and Meth-ods: Computed tomography data of a scoliotic patient was used for the construction of the lumbar models. The second and third vertebrae (L2-L3) of the lumbar spine, two facet joints, an intervertebral disc, and ligaments were constructed. A screw fixation system was employed and Von-Mises stress analysis was carried out for both models. Results: The von Mises stress distribution results showed that the presence of fixed implantation transmitted the compressive forces to the screws and rods in all directions and decreased the stress levels considerably by al-lowing to stabilize the model. The upper side of the L2 vertebra was the most affected region in flexion and lateral bending. However, the pedi-cle region had the maximum affected area under applied loads in ex-tension and axial rotation. Conclusion: It was concluded that a fixed implant system preserves the maintenance of the vertebral column and decreases the stress on the adjacent spinal segments, especially for the intervertebral discs.Öğe Investigation of optimum production conditions and the stability of ?-cyclodextrin-perfluorocarbon nanocone clusters for histotripsy applications(2024) Mustafa, Waleed; Hall, Sarah; Huynh, Laura; Mannasse, Rachel; Lüleburgaz, Serter; Vlaisavljevich, Eli; Yüksel Durmaz, YaseminNanocone clusters (NCCs) have been developed as clusters with inclusion complexes of FDA-approved ?-cyclodextrin (?CD) and perfluorocarbons (PFC) (i.e., perfluoropentane (PFP) and perfluorohexane (PFH)) and have shown promise in nanoparticle-mediated histotripsy (NMH) applications owing to their lowered cavitation threshold, ease of production, and fluorocarbon quantification. However, there is still a lack of information on the best conditions of the synthesis of NCCs as a product that can have a maximum determinable fluorocarbon content and maintain the stability of the NCC during synthesis and when used as histotripsy agents or exposed to physiological conditions. These concerns about the stability of the clusters and the best possible formulation are investigated in the current work. The cluster formation potential was tested taking into consideration the nature of both PFCs and ?CD by employing different synthesis conditions in terms of solution and environmental parameters such as concentration of solvent, stoichiometry between ?CD and PFCs, temperature, pH, solvent type, etc. The best route of synthesis was then translated into various batch sizes and investigated in terms of the PFC loading and yield. These studies revealed that preparing NCCs in double-distilled water in an ice bath at the optimized solution concentration gave the highest yields and optimal PFC loading, as determined from gas chromatography. Furthermore, the stability of the clusters with different stoichiometries was scrutinized in varying concentrations, mechanical disruption times, pH levels, and temperature conditions, showing effects on each cluster’s particle size in dynamic light scattering, visualized in transmission electron microscopy, and cavitation behavior in agarose gel tissue phantoms. These studies revealed stable clusters for all formulations, with PFH-containing NCCs emerging to be the most stable in terms of their cluster size and bubble formation potential in histotripsy. Finally, the shelf life of these clusters was investigated using DLS, which revealed a stable cluster. In conclusion, NCCs have shown high stability in terms of both synthesis, which can be replicated in gram-level production, and the cluster itself, which can be exposed to harsher conditions and still form stable bubbles in histotripsy.Öğe Hydrothermal performance of mini-channel heat sink using nanofluids/hybrid nanofluids: a numerical study(2024) Baig, Taha; Tariq, Hussain Ahmed; Anwar, Muhammad; Shoukat, Ahmad Adnan; Ali, Hafiz Muhammad; Janjua, Muhammad MansoorWe investigated hydrothermal performance of the mini-channel heat sink by using water, and nanofluids/hybrid nanofluids at 1% of volumetric concentration. The water-based nanofluids studied in this work were CuO, TiO2 and Fe2O3 with CuO-TiO2 and CuO-Fe2O3 hybrid combinations. The mean diameter of all the nanoparticles was fixed to be 60 nm. For numerical modeling, multiphase mixture model was used. The maximum heat transfer recorded for CuO and (CuO.75%+ Fe2O3.25%) based nanofluids was 59.12W and 58.27 W, respectively, at maximum Reynolds number of 1750. The maximum percentage increment in heat transfer recorded for CuO and hybrid (CuO.75%+Fe2O3.25%) water-based nanofluids was 29.24% and 24.55%, respectively, then water at minimum Reynolds number of 750. Results are evaluated in the form of the base temperature, thermal resistance, heat transfer, pressure drop and Nusselt number. The minimum base temperature was recorded for CuO-H2O as 35.4 at maximum Reynold number (Re) of 1750 among all the nanofluids/hybrid nanofluids. However, maximum percentage reduction in the base temperature was recorded for CuO-H2O as 7.04% compared with water at minimum Reynolds number of 750. It was observed that nanofluids lead toward high heat transfer.Öğe Optimizing percutaneous pulmonary valve implantation with patient-specific 3D-printed pulmonary artery models and hemodynamic assessment(Frontiers Media SA, 2024) Ödemiş, Ender; Aka, İbrahim Başar; Ali, Mhd Homam Alhaj; Gümüş, Terman; Pekkan, KeremBackground: Percutaneous pulmonary valve implantation (PPVI) has emerged as a less invasive alternative for treating severe pulmonary regurgitation after tetralogy of Fallot (TOF) repair in patients with a native right ventricular outflow tract (RVOT). However, the success of PPVI depends on precise patient-specific valve sizing, the avoidance of oversizing complications, and optimal valve performance. In recent years, innovative adaptations of commercially available cardiovascular mock loops have been used to test conduits in the pulmonary position. These models are instrumental in facilitating accurate pulmonic valve sizing, mitigating the risk of oversizing, and providing insight into the valve performance before implantation. This study explored the utilization of custom-modified mock loops to implant patient-specific 3D-printed pulmonary artery geometries, thereby advancing PPVI planning and execution.Material and Methods: Patient-specific 3D-printed pulmonary artery geometries of five patients who underwent PPVI using Pulsta transcatheter heart valve (THV) (R) were tested in a modified ViVitro pulse duplicator system (R). Various valve sizes were subjected to 10 cycles of testing at different cardiac output levels. The transpulmonary systolic and regurgitation fractions of the valves were also recorded and compared.Results: A total of 39 experiments were conducted using five different patient geometries and several different valve sizes (26, 28, 30, and 32 mm) at 3, 4, and 5 L/min cardiac output at heart rates of 70 beats per minute (bpm) and 60/40 systolic/diastolic ratios. The pressure gradients and regurgitation fractions of the tested valve sizes in the models were found to be similar to the pressure gradients and regurgitation fractions of valves used in real procedures. However, in two patients, different valve sizes showed better hemodynamic values than the actual implanted valves.Discussion: The use of 3D printing technology, electromagnetic flow meters, and the custom-modified ViVitro pulse duplicator system (R) in conjunction with patient-specific pulmonary artery models has enabled a comprehensive assessment of percutaneous pulmonic valve implantation performance. This approach allows for accurate valve sizing, minimization of oversizing risks, and valuable insights into hemodynamic behavior before implantation. The data obtained from this experimental setup will contribute to advancing PPVI procedures and offer potential benefits in improving patient outcomes and safety.Öğe Surgical and transcatheter pulmonary valve replacement in patients with repaired tetralogy of Fallot: Cardiac magnetic resonance imaging characteristics and morphology of right ventricular outflow tract(Springer, 2023) Özkök, Serçin; Çiftçi, Hatice Özge; Köse, Kevser Banu; Yücel, İlker Kemal; Şaşmazel, Ahmet; Çelebi, Ahmet; Pekkan, KeremBackgroundPulmonary valve replacement is recommended in patients with repaired tetralogy of Fallot based on cardiac magnetic resonance imaging (MRI) criteria. This procedure is performed by surgical or transcatheter approaches.ObjectiveWe aimed to investigate the differences in preprocedural MRI characteristics (volume, function, strain) and morphology of the right ventricular outflow tract and branch pulmonary arteries in patients for whom surgical or transcatheter pulmonary valve replacement was planned.Materials and methodsCardiac MRI of 166 patients with tetralogy of Fallot were analyzed. Of these, 36 patients for whom pulmonary valve replacement was planned were included. Magnetic resonance imaging characteristics, right ventricular outflow tract morphology, branch pulmonary artery flow distribution and diameter were compared between surgical and transcatheter groups. Spearman correlation and Kruskal-Wallis tests were performed.ResultsCircumferential and radial MRI strain for the right ventricle were lower in the surgical group (P=0.045 and P=0.046, respectively). The diameter of the left pulmonary artery was significantly lower (P=0.021) and branch pulmonary artery flow and diameter ratio were higher (P=0.044 and P = 0.002, respectively) in the transcatheter group. There was a significant correlation between right ventricular outflow tract morphology and right ventricular end-diastolic volume index and global circumferential and radial MRI strain (P=0.046, P=0.046 and P= 0.049, respectively).ConclusionPreprocedural MRI strain, right-to-left pulmonary artery flow, diameter ratio and morphological features of the right ventricular outflow tract were significantly different between the two groups. A transcatheter approach may be recommended for patients with branch pulmonary artery stenosis, since both pulmonary valve replacement and branch pulmonary artery stenting can be performed in the same session.Öğe Ionic liquid based treatment - A potential strategy to modify bacterial cellulose(Wiley, 2023) Munir, Muneeba; Muhammad, Nawshad; Uroos, Maliha; Mustafa, Waleed; Sharif, FaizaThe constant need for advanced materials led by modern research continues the exploitation of old remedies and innovation to find new solutions. The use of ionic liquids (ILs) as solvents has revolutionized modern chemical research. The non-toxic green technology has inspired new paradigms in chemical reactions and synthesis. Developing nontoxic materials for industrial and biomedical applications has endorsed the use of ILs in synthesis and fabrication. In terms of biomedical materials, the exploration for novel technologies to deal with chronic and nonhealing injuries desires degradable materials. One of the vastly used biomaterials is cellulose, which is nondegradable on its own unless digested by special enzymes produced by bacteria in nature. Bacterial cellulose (BC) is a naturally occurring more refined and purified form of cellulose which again is nondegradable on its own. Looking for technologies that can modify the BC in situ or ex situ is a challenge. This review is bound to give insight into the current scientific research being conducted to render BC degradable for biomedical applications. The data has been collected through Clarivate analysis, Google search, PubMed Central Identifier (PMCID), and Research Gate. The lack of available literature on this topic allowed us to include all the articles related to the subject as old as 1988 onwards.Öğe A rare ventriculoarterial connection: Double outlet of both ventricles(Cambridge University Press, 2023) Genç, Halise Zeynep; Özyılmaz, İsa; Baş, Serap; Köse, Banu; Öztürk, Erkut; Hatemi, Ali Can; Tanıdır, İbrahim CansaranVentriculoarterial connection is one of the important points of the segmental approach to congenital cardiac malformations. Double outlet of both ventricles is a rare form where both great arterial roots override the interventricular septum. In this article, we aimed to draw attention to this very rare form of ventriculoarterial connection by presenting an infant case diagnosed using echocardiography, CT angiography, and 3-dimensional modelling.Öğe Bioconjugated beta-cyclodextrin-perfluorohexane nanocone clusters as functional nanoparticles for nanoparticle-mediated histotripsy(American Chemical Society, 2022) Toydemir, Cemran; Hall, Sarah; Demirel, Erhan; Elmacı, Dilşah Nur; Göl, Deniz; Vlaisavljevich, Eli; Yüksel Durmaz, YaseminNanocone clusters (NCCs) are new-generation agents of nanoparticle-mediated histotripsy (NMH) recently developed to address the limitations of previously designed nanodroplets (NDs). NCCs can be obtained by simply mixing FDA-approved cyclodextrins (CD) and suitable perfluorocarbons (PFCs), which result in smaller size aggregates, detectable PFC amount, and more stable long-term storage since the obtained powder can be stored and redispersed as needed. Previous experimental and computational studies showed that NCCs consist of an organization of inclusion complexes of CD and PFC around free PFC droplets, and their aggregate behavior depends on the localization of PFC in the cavity and the water solubility of CD derivatives. It has been shown that beta-cyclodextrin (beta CD) and perfluorohexane (PFH) are ideal candidates for NCCs that can be isolated as a powder with high PFC content among various CD and PFC derivatives. This study focuses on the further development of the selected NCC composition to enhance the potential of NMH therapy while also enabling more detailed future experiments in vitro and in vivo. It is aimed to show the bioconjugation potential of NCCs through the example of the most commonly used functionalization methods such as targeting, PEGylation, and fluorescent labeling. For this purpose, beta CD as a building block was monofunctionalized with groups such as azide, alkyne, and amine groups that allow for effective coupling reactions such as the "click" reaction and N-(3-dimethylaminopropyl)-N '-ethylcarbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS) coupling. These monofunctional beta CDs were used as building blocks of NCCs in the presence of PFH to obtain functional NCCs as precursors of bioconjugation. EPPT1 as a synthetic peptide specific to uMUC1 and folic acid (FA) as the most commonly used targeting agent along with PEGylation were successfully shown as bioconjugation examples. Lastly, fluorescently labeled NCCs were obtained via fluorescein isothiocyanate (FITC) and alkyne functional NCC reaction through propargyl amine and isothiocyanate group reaction. The obtained bioconjugates were tested in vitro to validate the conjugation, and the ability to lower the histotripsy cavitation threshold, which is necessary for NMH, was demonstrated for all bioconjugates. Overall, the results showed that all obtained bioconjugates successfully lowered the cavitation threshold pressure while also fulfilling the desired bioconjugation metrics to serve as improved tools to enhance NMH as a targeted noninvasive ablation method.Öğe In-situ measurement of anisotropic Young’s modulus in fused deposition modeling printed cantilevers(IOP Publishing Ltd, 2023) Tekin, Engincan; Çağmel, Mehmet; Aydın, Can Ozan; Ferhanoğlu, Onur; Toy, Muhammed FatihIn this study, we investigate the effect of fused deposition modeling printing direction on the effective Young's modulus value of cantilevers. Through finite-element simulations and experiments with seven different dimensions and totaling over 100 cantilevers, we have observed the impact of printing direction on cantilever resonance. Unlike the conventional compressive and tensile stress-strain characterization, observation of the resonance allows for in-situ testing on the final device under test during operation. Initially, we observed the bulk filament modulus to be 4.5 GPa based on the optimal match between experiments and realistic finite element models expressing the internal structures of the longitudinal and transverse printed cantilevers. Then, the effective Young's modulus of the cantilevers is inferred through sweeping the Young's modulus that provides the best fit between the experiments, conventional cantilever formulations and finite-element simulations with solid, homogeneous, and isotropic cantilever model. Overall, we observed an average effective Young's modulus of 3.35 GPa for the cantilevers with longitudinal (along the cantilever axis) deposited filaments and an average effective Young's Modulus of 2.50 GPa for the transverse (perpendicular to the cantilever axis, along the width dimension) deposited Polylactic acid cantilevers. Eventually, simplified shape outline and effective Young's modulus for the corresponding printing direction eases the subsequent theoretical and simulation analyses. The presented methodology is also applicable to micrometric and sub-micrometric scale serial manufacturing techniques (i.e. two-photon polymerization) where the laser beams steering direction causes anisotropy in the mechanical properties of the device under test.Öğe Selective binding of pVTK peptide-and bisphosphonate-functionalized micelles to prostate cancer cells, osteoblasts, and osteoclasts(Andover House, Inc., 2022) Aydın, Ömer; Tiruchinapally, Gopinath; Youssef, Ibrahim; Ramaraju, Harsha; Yüksel Durmaz, Yasemin; Kozloff, Kenneth M.; Kohn, David H.; Elsayed, Mohamed E. H.This report describes the development of functionalized polymeric micelles encapsulating a chemotherapeutic agent. The results indicate the ability to achieve selective uptake into different cell populations in metastatic prostate cancer in vitro by appropriate selection of the targeting ligand. This paves the way for administering single or multiple therapeutic agents into bone metastases. These particles are functionalized to display the pVTK peptide of bisphosphonate (BP) as two different targeting ligands to assess their ability to trigger selective binding and internalization into prostate cancer cells, osteoblasts, osteoclasts, and macrophages in vitro. These bone-targeting particles (60-90 nm) bind to hydroxyapatite/bone powder with high affinity. Uptake of pVTK-and BP-conjugated particles into prostate cancer cells (PC-3 and C4-2B), MC3T3, RAW264.7 bone macrophages, and RANKL-activated RAW264.7 cells cultured on a regular tissue culture plate and bone-like surface was investigated. Results show that increasing the number of BP-targeting ligands displayed on particle surface shows 60-fold higher affinity to RAW 264.7 macrophages seeded on conventional tissue culture plates than non-conjugated particles. In addition, the uptake study results show that pVTK-functionalized particles were selectively internalized by C4-2B and MC3T3 osteoblast cells cultured on BLS, whereas BP-functionalized particles are selectively internalized by PC-3 and RAW264.7 macrophage cells cultured on BLS. Therefore, efficient and selective bone-conjugated therapies are needed to kill cancer cells and inhibit the crosstalk with other cells in the metastatic lesion, resulting in osteoblastic, osteolytic, or a mixed phenotype.Öğe Delivery of curcumin within emulsome nanoparticles enhances the anti-cancer activity in androgen-dependent prostate cancer cell(Springer, 2023) Bolat, Zeynep Büşra; İşlek, Zeynep; Şahin, Fikrettin; Üçışık, Mehmet HikmetBackground: Curcumin, a dietary polyphenol isolated from turmeric, is a potent phytochemical possessing intrinsic anticancer activities against various cancer types including prostate cancer. However, low water solubility and bioavailability of the compound are major challenges against its medical use. The objective of this study is to evaluate the therapeutic potential of curcumin-loaded emulsome nanoparticular system, i.e. CurcuEmulsomes, for the treatment of androgen dependent LNCaP prostate cancer cell line. Methods and results: The antiproliferative effect of both free curcumin and CurcuEmulsome were investigated comparatively on LNCaP and PNT1A cells. Cell viability data indicates that the inhibition in proliferation of LNCaP cells becomes more effective when curcumin is provided with its emulsome formulation rather than its free form. Corresponding to a therapeutic index of 2.25, Half maximal inhibitory (IC50) and cytotoxic (CC50) concentrations of CurcuEmulsomes for LNCaP and PNT1A cells were estimated as 17.1 µM and 38.6 µM, respectively. The fluorescence signal of autofluorescence curcumin was preserved within the CurcuEmulsomes at 72 h after the treatment. Thus, CurcuEmulsomes prolonged biological activity of curcumin. Induced apoptotic cell death and stimulated cell cycle arrest at G2/M phase were attributed to antiproliferative activity of CurcuEmulsomes. Treatment of LNCaP cells with CurcuEmulsomes increased expression of caspase-3 significantly by 11.76-fold, whereas decreased cyclin D1, Bcl-2 and AR expression levels significantly by of 0.18, 0.06 and 0.46-fold, respectively. Conclusions: Presented safety and anticancer activity of CurcuEmulsomes on LNCaP cell line highlights the potential of CurcuEmulsomes to benefit intrinsic anticancer activities of curcumin in androgen dependent prostate cancer therapy.Öğe A 3-DoF robotic platform for the rehabilitation and assessment of reaction time and balance skills of MS patients(Public Library of Science, 2023) Ersoy, Tuğçe; Hocaoğlu, ElifThe central nervous system (CNS) exploits anticipatory (APAs) and compensatory (CPAs) postural adjustments to maintain the balance. The postural adjustments comprising stability of the center of mass (CoM) and the pressure distribution of the body influence each other if there is a lack of performance in either of them. Any predictable or sudden perturbation may pave the way for the divergence of CoM from equilibrium and inhomogeneous pressure distribution of the body. Such a situation is often observed in the daily lives of Multiple Sclerosis (MS) patients due to their poor APAs and CPAs and induces their falls. The way of minimizing the risk of falls in neurological patients is by utilizing perturbation-based rehabilitation, as it is efficient in the recovery of the balance disorder. In light of the findings, we present the design, implementation, and experimental evaluation of a novel 3 DoF parallel manipulator to treat the balance disorder of MS. The robotic platform allows angular motion of the ankle based on its anthropomorphic freedom. Moreover, the end-effector endowed with upper and lower platforms is designed to evaluate both the pressure distribution of each foot and the CoM of the body, respectively. Data gathered from the platforms are utilized to both evaluate the performance of the patients and used in high-level control of the robotic platform to regulate the difficulty level of tasks. In this study, kinematic and dynamic analyses of the robot are derived and validated in the simulation environment. Low-level control of the first prototype is also successfully implemented through the PID controller. The capacity of each platform is evaluated with a set of experiments considering the assessment of pressure distribution and CoM of the foot-like objects on the end-effector. The experimental results indicate that such a system well-address the need for balance skill training and assessment through the APAs and CPAs.Öğe Characterization of Fc?RIa (CD64) as a ligand molecule for site-specific IgG1 capture: A side-by-side comparison with protein a(American Chemical Society, 2022) Çapkın, Eda; Kurt, Hasan; Gürel, Büşra; Bıçak, Dilan; Akgün Baş, Sibel; Dağlıkoca, Duygu Emine; Yüce, MeralFc ?receptors (Fc?Rs) are one of the structures that can initiate effector function for monoclonal antibodies. Fc?RIa has the highest affinity toward IgG1-type monoclonal antibodies among all Fc?Rs. In this study, a comprehensive characterization was performed for Fc?RIa as a potential affinity ligand for IgG1-type monoclonal antibody binding. The binding interactions were assessed with the SPR technique using different immobilization techniques such as EDC-NHS coupling, streptavidin-biotin interaction, and His-tagged Fc?RIa capture. The His-tagged Fc?RIa capture was the most convenient method based on assay repeatability. Next, a crude IgG1 sample and its fractions with different monomer contents obtained from protein A affinity chromatography were used to evaluate Fc?RIa protein in terms of monoclonal antibody binding capacity. The samples were also compared with a protein A-immobilized chip (a frequently used affinity ligand) for IgG1 binding responses. The antibody binding capacity of the protein A-immobilized chip surface was significantly better than that of the Fc?RIa-immobilized chip surface due to its 5 Ig binding domains. The antibody binding responses changed similarly with protein A depending on the monomer content of the sample. Finally, a different configuration was used to assess the binding affinity of free Fc?Rs (Fc?RIa, Fc?RIIa, and Fc?RIIIa) to three different immobilized IgGs by immobilizing protein L to the chip surface. Unlike previous immobilization techniques tested where the Fc?RIa was utilized as a ligand, nonimmobilized or free Fc?RIa resulted in a significantly higher antibody binding response than free protein A. In this configuration, kinetics data of Fc?RI revealed that the association rate (ka 50-80 × 105 M-1 s-1) increased in comparison to His capture method (1.9-2.4 × 105 M-1 s-1). In addition, the dissociation rate (kd 10-5 s-1) seemed slower over the His capture method (10-4 s-1) and provided stability on the chip surface during the dissociation phase. The KD values for Fc?RIa were found in the picomolar range (2.1-10.33 pM from steady-state affinity analysis and 37.5-46.2 pM from kinetic analysis) for IgG1-type antibodies. Fc?RIa possesses comparable ligand potential as well as protein A. Even though the protein A-immobilized surface bound more antibodies than the Fc?RIa-captured surface, Fc?RIa presented a significant antibody binding capacity in protein L configuration. The results suggest Fc?RIa protein as a potential ligand for site-oriented immobilization of IgG1-type monoclonal antibodies, and it needs further performance investigation on different surfaces and interfaces for applications such as sensing and antibody purification.
