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  • Öğe
    Pharmacist and child communication : a phenomenological multidisciplinary study from the perspectives of undergraduate students in pharmacy and child development
    (Elsevier, 2023) Fedai Kayın, İnci; Dere Çiftçi, Hale; Tan, Buket; Akoğlu, Merve Nur
    Background: The present study is an interdisciplinary study about pharmacist-child communication exploring the per ceptions and observations of students studying in two different but intersecting fields, which are pharmacy and child development. Objective: The objective of the study is to illustrate the perceptions and observations of undergraduate pharmacy and child development students about pharmacist-child communication. Method: The study is a phenomenological study and the phenomenon analyzed is “pharmacist-child communication”. Research study group was selected via criterion sampling method. The sample group consisted of 40 undergraduate pharmacy and child development students. “Demographic Information Form” was used as the data collection tool and “Focus Group Interview Guide” was prepared for focus group interview meetings. Ten open-ended questions aligned with the research objective were asked to the students in the focus group interview. The collected data were analyzed by descriptive analysis method and the experiences of these two different groups of students were explored. Results: At the end of the study, two main themes and five sub-themes were obtained. These themes and the sub-themes are as follows: adherence to drug therapy (Sub-themes: communication strategies relevant to the cognitive develop ment at various ages of the child, rewarding children and reinforcement of good behavior, role of the parent in pharmacist-child communication) and physical characteristics of the pharmacy/pharmacist (Sub-themes: physical characteristics of the pharmacy, physical caharacteristics of the pharmacist). Conclusions: Each theme was illustrated in the study with comments of the students. The results showed that the obser vation and perceptions of the students studying in two different fields agreed with each other and those of other re searchers. It is proposed that projects and practices can be developed by these two different disciplines, pharmacy and child development are two intersecting fields. As they complement each other, they could strengthen the pharmacist-child communication and as a result support the child's adherence to therapy.
  • Öğe
    Crystal structure of bis(mesityl)(pyrrol-1-yl)borane
    (Int Union Crystallography, 2022) Şahin, Onur; Wallis, John D
    In the crystal structure of the title compound, C22H26BN, the B atom acts to reduce the delocalization of the nitrogen lone-pair electron density into the pyrrole ring, so that the two N-C bonds increase in length to 1.4005 (14) and 1.3981 (14) A degrees. The N-B bond length is 1.4425 (15) A degrees, which is longer than a typical N-B bond because the nitrogen lone pair is not fully available to participate in the bond.
  • Öğe
    A simple spray assisted extraction/preconcentration of cadmium from sunflower oil, olive oil and hazelnut oil samples prior to flame atomic absorption spectrometry determination
    (Academic Press Inc., 2023) Erarpat, Sezin; Bakırdere, Sezgin; Bodur, Süleyman; Tutar, Ömer Faruk
    In this study, an efficient and simple analytical approach for the preconcentration and extraction of cadmium from sunflower oil, olive oil and hazelnut oil samples using environmentally friendly, easy and efficient vortex assisted reverse phase spray-based fine droplet formation liquid phase microextraction (VA-RP-SFDF-LPME) prior to flame atomic absorption spectrometry (FAAS) measurement was proposed. Limit of detection (LOD)/limit of quantification (LOQ) values were calculated as 2.89/9.62 µg/kg, 2.00/6.68 µg/kg and 4.77/15.92 µg/kg for sunflower oil, olive oil and hazelnut oil, respectively. Recovery experiments were carried out for the evaluation of applicability and accuracy of the developed method. Satisfactory recovery results for hazelnut oil, olive oil and sunflower oil samples were recorded in the range of 92.8 – 111.9%, 96.6 – 108.2% and 90.0 – 105.7%, respectively. These results verified that the proposed method can be accurately applied to the hazelnut oil, olive oil and sunflower oil samples to qualify/quantify their cadmium content. © 2023 Elsevier Inc.
  • Öğe
    A cross-sectional study of community pharmacists' self-reported disease knowledge and competence in the treatment of childhood autism spectrum disorder
    (SPRINGER NATURE, 2022) Yılmaz, Zekiye; Al-Taie, Anmar
    Background Autism spectrum disorder (ASD) is a neurodevelopmental disease that can cause signifcant social, communication, and behavioural challenges. Given the rising prevalence of autism and multiple medication use, healthcare professionals, including community pharmacists, are required to have sufcient ASD knowledge to afect positively the disease prognosis and related comorbidities. Aim To assess community pharmacists’ knowledge of disease and pharmacotherapy of ASD, along with the provision of patient education and counselling provided by, community pharmacists in Turkey. Method This was a descriptive, cross-sectional study conducted among community pharmacists in Turkey using a structured, validated questionnaire to assess ASD knowledge, awareness, and the provision of patient education and counselling by community pharmacists. Results 486 community pharmacists were included, with a mean age of 39.69±13.10 years, and most (n=151, 31.1%) in the age range between 20 and 29 years. 96.3% of community pharmacists never had training about ASD. 32.9% of the participants were aware of the medicines for ASD treatment, and 25.7% were aware of the drugs’ side efects. The mean overall knowledge about childhood autism among health workers questionnaire (KCAHW) score was 11.83±3.91, and there was a statistically signifcant KCAHW score diference between other pharmacists and those with ASD training (p=0.006). Conclusion There is a lack of disease and pharmacotherapy knowledge about childhood ASD among Turkish community pharmacists, particularly about communication impairment, type, onset, and comorbidities, as well as poor knowledge about drug pharmacotherapy and patient counselling services. This potentially creates a barrier to the adequate provision of healthcare to autistic patients.
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    Optimization of methacrylated gelatin /layered double hydroxides nanocomposite cell-laden hydrogel bioinks with high printability for 3D extrusion bioprinting
    (John Wiley and Sons Inc, 2022) Alarçin, Emine; İzbudak, Burçin; Yüce Erarslan, Elif; Domingo, Sherif; Tutar, Rümeysa; Titi, Kariman; Kocaağa, Banu; Güner, F. Seniha; Bal Öztürk, Ayça
    Layered double hydroxides (LDHs) offer unique source of inspiration for design of bone mimetic biomaterials due to their superior mechanical properties, drug delivery capability and regulation cellular behaviors, particularly by divalent metal cations in their structure. Three-dimensional (3D) bioprinting of LDHs holds great promise as a novel strategy thanks to highly tunable physiochemical properties and shear-thinning ability of LDHs, which allow shape fidelity after deposition. Herein, we introduce a straightforward strategy for extrusion bioprinting of cell laden nanocomposite hydrogel bioink of gelatin methacryloyl (GelMA) biopolymer and LDHs nanoparticles. First, we synthesized LDHs by co-precipitation process and systematically examined the effect of LDHs addition on printing parameters such as printing pressure, extrusion rate, printing speed, and finally bioink printability in creating grid-like constructs. The developed hydrogel bioinks provided precise control over extrudability, extrusion uniformity, and structural integrity after deposition. Based on the printability and rheological analysis, the printability could be altered by controlling the concentration of LDHs, and printability was found to be ideal with the addition of 3 wt % LDHs. The addition of LDHs resulted in remarkably enhanced compressive strength from 652 kPa (G-LDH0) to 1168 kPa (G-LDH3). It was shown that the printed nanocomposite hydrogel scaffolds were able to support encapsulated osteoblast survival, spreading, and proliferation in the absence of any osteoinductive factors taking advantage of LDHs. In addition, cells encapsulated in G-LDH3 had a larger cell spreading area and higher cell aspect ratio than those encapsulated in G-LDH0. Altogether, the results demonstrated that the developed GelMA/LDHs nanocomposite hydrogel bioink revealed a high potential for extrusion bioprinting with high structural fidelity to fabricate implantable 3D hydrogel constructs for repair of bone defects.
  • Öğe
    Gelatin methacryloyl/nanosilicate nanocomposite hydrogels encapsulating dexamethasone with a tunable crosslinking density for bone repair
    (Editions de Sante, 2022) Alarçin, Emine; Dokgöz, Ayşe Begüm; Akgüner Püren, Zeynep; Seki, Hatice Kübra; Bal Öztürk, Ayça
    Despite various strategies have been proposed to accelerate bone regeneration, the treatment of bone defects in critical size still remains a clinical challenge. In this study, we fabricated nanocomposite gelatin methacryloyl (GelMA)/nanosilicate (NS) hydrogels for the delivery of dexamethasone (DEX), and systematically investigated their performance in drug delivery for bone repair. Nanocomposite hydrogels were fabricated by mold casting, and exposed to ultraviolet (UV) light to induce covalent crosslinking. Afterwards, we conducted a systematic characterization study to determine the effects of varying NS concentration, GelMA methacrylation degree and UV exposure time on mechanical, structural, and drug release behaviors of nanocomposite hydrogels. In particular, the higher methacrylation degree of GelMA, longer UV exposure and the presence of NS exhibited gradually enhanced mechanical properties. For instance, the compressive strengths of nanocomposite hydrogels containing 0% (w/v) NS (G0NS120) and 3% (w/v) NS (G3NS120) at 120 s of UV exposure were 194.816 kPa–367.284 kPa (p < 0.001), respectively. Similarly, they exhibited higher swelling ratio (%) and slower degradation rate (%) with longer UV exposure and increased NS amount. Nanocomposite hydrogels revealed slower drug release rate due to longer UV exposure and increased NS amount. At day 14 of the release study, 99.53% and 60.687% of DEX were released from G0NS120 and G3NS120, respectively. Particularly, the nanocomposite GelMA/ NS hydrogels supported osteoblast adhesion well, and NS and DEX exhibited synergistic effect on osteoblast proliferation with 5.01 fold increase after 7 days of culture. Our results clearly showed that GelMA/NS nanocomposite hydrogels with tunable physiochemical and drug carrier properties could provide a favorable option for accelerating bone repair.
  • Öğe
    The effect of thiol functional groups on bovine serum albumin/chitosan buccal mucoadhesive patches
    (Editions de Sante, 2022) Bal Öztürk, Ayça; Alarçin, Emine; Özbaş, Zehra; Özkahraman, Bengi; Torkay, Gülşah
    In this research, the effect of thiol functional groups on bovine serum albumin (BSA)/chitosan (Chi) based buccal mucoadhesive patch was investigated. Thiolated BSA (BSA-SH) was prepared via 2-mercaptoethanol. FTIR and 1H NMR results confirmed that BSA-SH was synthesized successfully. The buccal mucoadhesive patches were fabricated by the solvent casting method. Following the structural characterization of BSA/Chi and BSA-SH/Chi buccal patches, the mechanical characterization was performed by tensile tests. The drug release from triam- cinolone acetonide (TR) loaded buccal patches was evaluated in-vitro in simulated salivary. According to the ex- vivo buccal adhesion experiments, the mechanical and mucoadhesion properties of BSA-SH/Chi buccal patch had improved compared to BSA/Chi buccal patch. The total cumulative TR permeated after 12 h was higher for BSA- SH/Chi than BSA/Chi buccal patches. The developed mucoadhesive buccal patches were found to be biocom- patible in vitro. To conclude, the thiolated BSA-SH/Chi buccal adhesive patch is a promising biomaterial for a satisfied drug delivery, which provides advantages for various oral applications.
  • Öğe
    Bioadhesive nanoparticles as potent drug delivery carriers
    (Bentham Science Publishers, 2022) Rençber, Seda; Özcan Bülbül, Ece; Ay Şenyiğit, Zeynep; Üstündağ Okur, Neslihan; Siafaka, Panoraia
    Background: Last years, nanotechnology-based systems have gained the interest of numerous scientists, especially for biomedical applications. Then, as called, nanocarriers present tunable abilities, can be easily functionalized to target specific epithelial cells, tissues, and organs while various materials can be chosen and generate nanosized particles. At the present, nanoparticles that possess bioadhesion have been studied as potent drug carriers since they can easier penetrate and target organs. Objective: Aim of this study was to explore the various applications of the bioadhesive nanoparticles found in the literature. Method: Authors have studied the literature finding that bioadhesive nanoparticles can be administered via routes such as oral, topical, ocular, dermal, vaginal, etc according to the clinician’s opinion and treatment choice. Therefore, the knowledge of general characteristics of bioadhesive nanoparticles, the bioadhesion theory, and other properties of nanoparticles should be known for the development of innovative bioadhesive drug nanocarriers. Results: In this review article, the authors state the current knowledge of bioadhesion theories. In addition, the present categories of nanoparticles and their basic characteristics are also discussed. Finally, the biomedical applications of bioadhesive nanocarriers and the several administration routes are extensively reviewed. Conclusion: The review article aims to cover the most current bioadhesive nanoparticles for drug delivery to assist any scientist who desires to study or develop innovative bioadhesive formulations.
  • Öğe
    Antivirals and the potential benefits of orally Inhaled Drug Administration in COVID-19 Treatment
    (Elsevier Science, 2022) Şahin, Gökben; Akbal-Dağıstan, Özlem; Çulha, Meltem; Ertürk, Aybige; Başarır, Nur Sena; Yıldız-Peköz, Ayça
    Coronavirus Disease 2019 (COVID-19) pandemic has been on the agenda of humanity for more than 2 years. In the meantime, the pandemic has caused economic shutdowns, halt of daily lives and global mobility, overcrowding of the healthcare systems, panic, and worse, more than 6 million deaths. Today, there is still no specific therapy for COVID-19. Research focuses on repurposing of antiviral drugs that are licensed or currently in the research phase, with a known systemic safety profile. However, local safety profile should also be evaluated depending on the new indication, administration route and dosage form. Additionally, various vaccines have been developed. But the causative virus, Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), has undergone multiple variations, too. The premise that vaccines may suffice to eradicate new and all variants is unreliable, as they are based on earlier versions of the virus. Therefore, a specific medication therapy for COVID-19 is crucial and needed in order to prevent severe complications of the disease. Even though there is no specific drug that inhibits the replication of the disease-causing virus, among the current treatment options, systemic antivirals are the most medically appropriate. As SARS-CoV-2 directly targets the lungs and initiates lung damage, treating COVID-19 with inhalants can offer many advantages over the enteral/parenteral administration. Inhaled drug delivery provides higher drug concentration, specifically in the pulmonary system. This enables the reduction of systemic side effects and produces a rapid clinical response. In this article, the most frequently (systemically) used antiviral compounds are reviewed including Remdesivir, Favipiravir, Molnupiravir, Lopinavir- Ritonavir, Umifenovir, Chloroquine, Hydroxychloroquine and Heparin. A comprehensive literature search was conducted to provide insight into the potential inhaled use of these antiviral drugs and the current studies on inhalation therapy for COVID-19 was presented. A brief evaluation was also made on the use of inhaler devices in the treatment of COVID-19. Inhaled antivirals paired with suitable inhaler devices should be considered for COVID-19 treatment options
  • Öğe
    Tixagevimab and cilgavimab: Can we see more recommendations for monoclonal antibodies beyond COVID-19 vaccination
    (Cambridge University Press, 2022) Al-Taie, Anmar
    Nearly three years after its detection, coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome CoV-2, is still a life-threatening global pandemic health disease that contributed to a high progression and mortality. This imposes the scientific researching efforts to hold intense interest directed to explore for the development and optimizing different interventions to COVID-19 infection. This commentary summarizes the potential clinical benefits for the recently authorized immunotherapy combination of tixagevimab and cilgavimab monoclonoal antibodies for the prevention and treatment of COVID-19.
  • Öğe
    The effect of LDHs nanoparticles on the cellular behavior of stem cell-laden 3D-bioprinted scaffold
    (SAGE PUBLICATIONS, 2022) İzbudak, Burçin; Bal Öztürk, Ayça
    Three-dimensional (3D)-bioprinting as an emerging approach for tissue engineering possesses the promise to create highly mimicked organs or tissues by using computer-aided design. For biomedical applications in tissue engineering in our previous work, we developed an optimized nanocomposite bioink based on methylacrylated gelatin (GeIMA), methylacrylated chitosan (ChitMA), and double-layered hydroxide (LDHs) nanoparticles by using 3D-bioprinting technology. Herein, we used the previous formulation to fabricate human bone marrow mesenchymal stem cells (hBMMSCs)-laden nanocomposite bioinks. The effect of LDHs nanoparticles on the cellular behaviors of the encapsulated-hBMMSCs in the scaffolds was evaluated for the first time. Live/Dead, PrestoBlue, and DAPI/Actin analysis were carried out to assess the cell viability, proliferation rate, and cellular morphology of encapsulated hBMMSCs within the scaffolds. In addition, osteogenic differentiation studies were performed culturing the scaffolds for up to 21 days. Results show that LDHs nanoparticles in the GeIMA/ChitMA scaffold formulation increased the viability of hBMMSCs, did not cause any adverse effect on the proliferation rate, cell morphology of the hBMMSCs, and increased the Runx2 protein expression of the encapsulated-hBMMSCs in the scaffolds. This study progresses the LDHs containing nanocomposite bioink for cell printing applications in tissue engineering.
  • Öğe
    Isolation and identification of listeria spp. from white cheese samples presented for consumption in Istanbul
    (TR- Dizin, 2021) Kaya, Nil; Arslan Aydoğdu, Elif Özlem; Kimiran, Ayten
    In this study, 119 feta cheese samples taken from different vendors in Istanbul were examined for the presence of Listeria monocytogenes. Isolates were confirmed by the PCR method using iap and hlyA primers, and the antibiotic susceptibility of the identified strains was performed by the Kirby-Bauer protocol. Seven Listeria spp. were isolated from three (2.52%) of 119 cheese samples analyzed. The seven Listeria spp. obtained from these three samples were found to contain the iap gene region but not the hlyA gene region. As a result of the sequence analysis using the 16S rRNA gene region, it was determined that these isolates were L. seeligeri. As a result of antibiotic susceptibility tests, it was observed that L. seeligeri isolates showed ciprofloxacin (85.71%) and penicillin (42.85%) resistance. All strains were susceptible to amikacin, amoxicillin/clavulanic acid, chloramphenicol, rifampin, gentamicin, cefaclor, ampicillin, trimethoprim-sulfamethoxazole, tetracycline, vancomycin, and clarithromycin antibiotics. The detection of Listeria spp. isolates in feta cheese samples made with pasteurized milk revealed that packaging, distribution, and storage practices following the pasteurization process should be followed more strictly. It is recommended to apply controls at each stage to prevent contamination.
  • Öğe
    Can lactate dehydrogenase inhibition be increased efficiency of 1,25(oh) 2 d 3 vitamin in prostate cancer animal model?
    (Wiley, 2022) Çakıcı, Çağrı; Daylan, Benay; Ayla, Şule; Yiğit, Pakize; Yavuz Dokgöz, Elif; Yiğitbaşı, Türkan
    The Warburg effect explains that the cancer cell's metabolism is programmed based on anaerobic glycolysis to support the proliferation and anabolic growth of cancer cells. LDH-A is the form of LDH found in cancer cells, which is the main regulator of anaerobic glycolysis. Increased LDH-A activity; promotes tumor growth and metastasis, increases migration and invasion. The active form of vitamin D (1,25(OH)2 D3 ), can have a protective effect against cancer by acting on apoptosis induction, stimulation of cell differentiation, anti-inflammatory, anti-proliferative effect, angiogenesis, and invasion through different mechanisms. We hypothesis that reprogramming cancer cell's glucose metabolism to oxidative phosphorylation with LDH-A inhibitor will increase the effectiveness of 1,25(OH)2 D3 vitamin in prostate cancer (PCa). For this purpose, 50 male C57BL/6 mice and Tramp-C2 PCa cell lines were used to develop PCa model (1- Control group; 2- PCa control group; 3- 1,25(OH)2 D3 vitamin group (5 µg/kg 1,25(OH)2 D3 vitamin); 4- LDH-A inhibitor (300 mg/kg sodium oxamate) group; 5- Combined group (LDH-A inhibitor + 1,25(OH)2 D3 ). CK18-M30, lactate and oxidative stress values were calculated from serum samples. TUNEL staining for apoptosis analysis, western blot analysis for epithelial to mesenchymal transition (EMT) to evaluate metastasis were performed from tumor tissue samples. Hematoxylin-eosin staining (HE) was performed in the liver and periodic acid schiff staining (PAS) was performed in the kidney tissues to evaluate toxicity. When the serum lactate levels were examined, it was shown that the LDH-A inhibitor reversed the Warburg effect. 1,25(OH)2 D3 , LDH-A inhibitor, and LDH-A inhibitor + 1,25(OH)2 D3 treatment groups significantly increased oxidative stress and apoptosis (p<0.05). Moreover, 1,25(OH)2 D3 treatment group had more toxic effect on the kidney. However, when the two treatments groups were combined, the toxicity of vitamin D was significantly decreased (p<0.05). In the liver, the combined treatment group had more toxic effects than other experimental groups (p>0.05). When the effect on EMT was examined, it was observed that the 1,25(OH)2 D3 , LDH-A inhibitor increased the expression of E-cadherin and decreased the expression of N-cadherin (p<0.05). There was no significant difference between EMT transcription factors in terms of treatment groups (p>0.05). Our results suggest that LDH-A inhibitor + 1,25(OH)2 D3 combined treatment group increased apoptosis, oxidative stress, and decreased toxic effect of 1,25(OH)2 D3 in the kidney. So, tumor volume was decreased and the effectiveness of 1,25(OH)2 D3 vitamin was increased. For metastasis, E-cadherin was increased, and N-cadherin was decreased in the LDH-A inhibitor and 1,25(OH)2 D3 vitamin group. However, the transcription factors results were contradictory. For this reason, EMT results needed to be further research to understand the mechanism. Taken together, our current data indicate that LDH-A inhibitor reprogrammed glucose metabolism and increased effectiveness of 1,25(OH)2 D3 vitamin in PCa animal model.
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    Coronary microvascular dysfunction is common in patients hospitalized with COVID-19 infection
    (Wiley, 2022) Atıcı, Adem; Çalışkan, Mustafa; Baycan, Ömer Faruk; Çelik, Fatma Betül; Güvenç, Tolga Sinan; Çağ, Yasemin; Konal, Oğuz; Bilgili, Ümmühan Zeynep; Ağırbaşlı, Mehmet Ali; Irgı, Tuğçe
    Background and Aims: Microvascular disease is considered as one of the main drivers of morbidity and mortality in severe COVID-19, and microvascular dysfunction has been demonstrated in the subcutaneous and sublingual tissues in COVID-19 patients. The presence of coronary microvascular dysfunction (CMD) has also been hypothe-sized, but direct evidence demonstrating CMD in COVID-19 patients is missing. In the present study, we aimed to investigate CMD in patients hospitalized with COVID-19, and to understand whether there is a relationship between biomarkers of myocardial injury, myocardial strain and inflammation and CMD.Methods:39 patients that were hospitalized with COVID-19 and 40 control subjects were included to the present study. Biomarkers for myocardial injury, myocardial strain, inflammation, and fibrin turnover were obtained at admission. A comprehen-sive echocardiographic examination, including measurement of coronary flow veloc -ity reserve (CFVR), was done after the patient was stabilized.Results:Patients with COVID-19 infection had a significantly lower hyperemic cor -onary flow velocity, resulting in a significantly lower CFVR (2.0 ± 0.3 vs. 2.4 ± 0.5, p< .001). Patients with severe COVID-19 had a lower CFVR compared to those with moderate COVID-19 (1.8 ± 0.2 vs. 2.2 ± 0.2, p< .001) driven by a trend toward higher basal flow velocity. CFVR correlated with troponin (p= .003, r: ?.470), B- type natriu-retic peptide (p< .001, r: ?.580), C- reactive protein (p< .001, r: ?.369), interleukin-6 (p< .001, r: ?.597), and d- dimer (p< .001, r: ?.561), with the three latter biomarkers having the highest areas-under- curve for predicting CMD.Conclusions:Coronary microvascular dysfunction is common in patients with COVID-19 and is related to the severity of the infection. CMD may also explain the “cryptic” myocardial injury seen in patients with severe COVID-19 infection.
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    Enzyme-mediated Alleviation of Peroxide Toxicity in Self-oxygenating Biomaterials
    (2022) Willemen, Niels G. A.; Hassan, Shabir; Gurian, Melvin; Jasso-Salazar, Maria Fernanda; Fan, Kai; Wang, Haihang; Becker, Malin; Allijn, Iris E.; Bal Öztürk, Ayça; Leijten, Jeroen; Shin, Su Ryon
    Oxygen releasing biomaterials can facilitate the survival of living implants by creating environments with a viable oxygen level. Hydrophobic oxygen generating microparticles (HOGMPs) encapsulated calcium peroxide (CPO) have recently been used in tissue engineering to release physiologically relevant amounts of oxygen for several weeks. However, generating oxygen using CPO is mediated via the generation of toxic levels of hydrogen peroxide (H2 O2 ). The incorporation of antioxidants, such as catalases, could potentially reduce H2 O2 levels. However, the formulation in which catalases can most effectively scavenge H2 O2 within oxygen generating biomaterials has remained unexplored. In this study, four distinct catalase incorporation methods were compared based on their ability to decrease H2 O2 levels. Specifically, catalase was incorporated within HOGMPs, or absorbed onto HOGMPs, or freely laden into the hydrogel entrapping HOGMPs and compared with control without catalase. Supplementation of free catalase in an HOGMP-laden hydrogel significantly decreased H2 O2 levels reflecting a higher cellular viability and metabolic activity of all the groups. An HOGMP/catalase-laden hydrogel precursor solution containing cells was used as an oxygenating bioink allowing improved viability of printed constructs under severe hypoxic conditions. The combination of HOGMPs with a catalase-laden hydrogel has the potential to decrease peroxide toxicity of oxygen generating tissues. This article is protected by copyright. All rights reserved.
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    Laurus nobilis L. Essential Oil-Loaded PLGA as a Nanoformulation Candidate for Cancer Treatment
    (MDPI, 2022) Ercin, Esin; Kecel-Gündüz, Serda; Gök, Bahar; Aydın, Tuğba; Budama-Kılınç, Yasemin; Kartal, Murat
    The aim of this study was to obtain essential oil (LNEO) from the Laurus nobilis L. plant, and to prepare LNEO-loaded poly lactic-co-glycolic acid (PLGA) nanoparticles (NPs) as an approach in cancer treatment. The components of the obtained LNEO were analyzed using GC-MS. The LNEO-NPs were synthesized by the single-emulsion method. The LNEO-NPs were charac-terized using UV-Vis spectrometry, Dynamic Light Scattering (DLS), Scanning Electron Microscopy (SEM), and a DNA binding assay, which was performed via the UV-Vis titration method. According to the results, the LNEO-NPs had a 211.4 ± 4.031 nm average particle size, 0.068 ± 0.016 PdI, and ?7.87 ± 1.15 mV zeta potential. The encapsulation efficiency and loading capacity were calculated as 59.25% and 25.65%, respectively, and the in vitro drug release study showed an LNEO release of 93.97 ± 3.78% over the 72 h period. Moreover, the LNEO was intercalatively bound to CT-DNA. In addition, the mechanism of action of LNEO on a dual PI3K/mTOR inhibitor was predicted, and its antiproliferative activity and mechanism were determined using molecular docking analysis. It was concluded that LNEO-loaded PLGA NPs may be used for cancer treatment as a novel phytotherapeutic agent-based controlled-release system. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.
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    Selection of natural biomaterials for micro-tissue and organ-on-chip models
    (2022) Bal Öztürk, Ayça; Cecen, Berivan; Yaşayan, Gökçen; Alarçin, Emine; Koçak, Polen; Tutar, Rümeysa; Kozacı, Leyla Didem; Ryon Shin, Su; K Miri, Amir
    The desired organ in micro-tissue models of organ-on-a-chip (OoC) devices dictates the optimum biomaterials, divided into natural and synthetic biomaterials. They can resemble biological tissues' biological functions and architectures by constructing bioactivity of macromolecules, cells, nanoparticles, and other biological agents. The inclusion of such components in OoCs allows them having biological processes, such as basic biorecognition, enzymatic cleavage, and regulated drug release. In this report, we review natural-based biomaterials that are used in OoCs and their main characteristics. We address the preparation, modification, and characterization methods of natural-based biomaterials and summarize recent reports on their applications in the design and fabrication of micro-tissue models. This article will help bioengineers select the proper biomaterials based on developing new techn
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    Development of mucoadhesive modified kappa-carrageenan/pectin patches for controlled delivery of drug in the buccal cavity
    (Wiley, 2021) Özkahraman, Bengi; Özbaş, Zehra; Yaşayan, Gökçen; Püren Akgüner, Zeynep; Yarımcan, Filiz; Alarçin, Emine; Bal Öztürk, Ayça
    In this study, modified kappa-carrageenan/pectin hydrogel patches were fabricated for treatment of buccal fungal infections. For this purpose, kappa-carrageenan-g-acrylic acid was modified with different thiolated agents (L-cysteine and 3-mercaptopropionic acid), and the thiol content of the resulting modified kappa-carrageenan was confirmed by elemental analyzer. Then, the hydrogel patches were fabricated, and characterized by Fourier-transform infrared spectroscopy, thermogravimetric analysis, ex vivo mucoadhesion test, and swelling behavior. Triamcinolone acetonide was added either directly or by encapsulating within the poly(lactic-co-glycolic acid) nanoparticles. The release amount of the drug from the directly loaded patch was 7.81 mg/g polymer, while it was 3.28 mg/g polymer for the encapsulated patch with the same content at 7 hr. The hydrogel patches had no cytotoxicity by cell culture studies. Finally, the drug loaded hydrogel patches were demonstrated antifungal activity against Aspergillus fumigatus and Aspergillus flavus. These results provide that the novel modified kappa-carrageenan and pectin based buccal delivery system has promising antifungal property, and could have advantages compared to conventional buccal delivery systems.
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    Layered double hydroxide-based nanocomposite scaffolds in tissue engineering applications
    (Royal Society of Chemistry, 2021) İzbudak, Burçin; Çeçen, Berivan; Anaya, Ingrid; Kamal Miri, Amir; Bal Öztürk, Ayça; Karaöz, Erdal
    Layered double hydroxides (LDHs), when incorporated into biomaterials, provide a tunable composition, controllable particle size, anion exchange capacity, pH-sensitive solubility, high-drug loading efficiency, efficient gene and drug delivery, controlled release and effective intracellular uptake, natural biodegradability in an acidic medium, and negligible toxicity. In this review, we study potential applications of LDH-based nanocomposite scaffolds for tissue engineering. We address how LDHs provide new solutions for nanostructure stability and enhancein vivostudies' success. © The Royal Society of Chemistry 2021.
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    Application of magnetic resonance imaging in liver biomechanics: a systematic review
    (Frontiers, 2021) Seyedpour, Seyed M.; Nabati, Mehdi; Lambers, Lena; Nafisi, Sara; Tautenhahn, Hans-Michael; Sack, Ingolf; Reichenbach, Jurgen R.
    MRI-based biomechanical studies can provide a deep understanding of the mechanisms governing liver function, its mechanical performance but also liver diseases. In addition, comprehensive modeling of the liver can help improve liver disease treatment. Furthermore, such studies demonstrate the beginning of an engineering-level approach to how the liver disease affects material properties and liver function. Aimed at researchers in the field of MRI-based liver simulation, research articles pertinent to MRI-based liver modeling were identified, reviewed, and summarized systematically. Various MRI applications for liver biomechanics are highlighted, and the limitations of different viscoelastic models used in magnetic resonance elastography are addressed. The clinical application of the simulations and the diseases studied are also discussed. Based on the developed questionnaire, the papers' quality was assessed, and of the 46 reviewed papers, 32 papers were determined to be of high-quality. Due to the lack of the suitable material models for different liver diseases studied by magnetic resonance elastography, researchers may consider the effect of liver diseases on constitutive models. In the future, research groups may incorporate various aspects of machine learning (ML) into constitutive models and MRI data extraction to further refine the study methodology. Moreover, researchers should strive for further reproducibility and rigorous model validation and verification.