Eczacılık Fakültesi / Faculty of Pharmacy
Permanent URI for this collectionhttps://hdl.handle.net/11727/5700
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Item A Bayesian Estimation Framework for Pharmacogenomics Driven Warfarin Dosing: A Comparative Study(2015) Oztaner, Serdar Murat; Temizel, Tugba Taskaya; Erdem, S. Remzi; Ozer, Mahmut; 0000-0002-7537-2170; 25020183; AAJ-2370-2021The incorporation of pharmacogenomics information into the drug dosing estimation formulations has been shown to increase the accuracy in drug dosing and decrease the frequency of adverse drug effects in many studies in the literature. In this paper, an estimation framework based on the Bayesian structural equation modeling, which is driven by pharmacogenomics, is proposed. The results show that the model compares favorably with the linear models in terms of prediction and explaining the variations in warfarin dosing.Item Preparation and in vitro/in vivo evaluation of flurbiprofen nanosuspension-based gel for dermal application(2020) Oktay, Ayse Nur; Ilbasmis-Tamer, Sibel; Han, Sevtap; Uludag, Orhan; Celebi, Nevin; 32937211; AAL-6931-2021Flurbiprofen (FB) is an analgesic and anti-inflammatory drug, but its low water solubility (BCS Class II) limits its dermal bioavailability. The aim of this study is to develop a FB nanosuspension (NS) based gel and to evaluate its analgesic and anti-inflammatory activities in rats. FB-NS was produced by the wet milling method with Plantacare 2000 (R), as stabilizer. The FB-NS was then incorporated in different carrier gels such as hydroxypropyl methyl cellulose (HPMC), polycarbophil, oleogel, and chitosan. To select the optimum gel type, visual examinations, pH and rheological property measurements, texture profile analysis, in vitro release and ex vivo permeation studies were performed. Following these tests, the analgesic and anti-inflammatory activities of the optimum NS based gel were evaluated using the tail flick and carrageenan-induced paw edema methods consecutively. The NS was successfully prepared with the wet milling method, and the PS, PDI and ZP values were found to be 237.7 +/- 6.8 nm, 0.133 +/- 0.030, and -30.4 +/- 0.7 mV; respectively. Among the NS-based gels, HPMC gel showed more suitable rheological and mechanical properties, also the percentage of permeated FB and the flux value observed for HPMC gel were higher for HPMC than for the other gels. Thus, HPMC gel was selected as a carrier gel for in vivo pharmacodynamics studies. The anti-inflammatory activity of FB-NS HPMC gel was higher than that of the physical mixture gel and that of the coarse suspension gel. Results of our analgesic activity studies showed that, in the 180th min of FB nanosuspension treatment, the latency time was significantly prolonged compared to that of the control group (p<0.05). As a conclusion, while nanosuspensions increased the in vivo pharmacodynamics effect of FB by means of nanosized particles and a large surface area, the HPMC gel as a carrier prolonged the contact time of NSs with skin and eased the dermal application.Item Editorial, Special Issue BBBB(2021) Celebi, Nevin; Sahin, Selma; 33571635; AAL-6931-2021Item QbD based formulation optimization of semi-solid lipid nanoparticles as nano-cosmeceuticals(2021) Tarimci, NiluferNano-cosmeceuticals are cosmetic formulations containing nano-drug delivery systems to carry cosmetic active molecules to the relevant skin tissues. The purpose of this research is to develop and optimize the semi-solid nanostructured lipid carriers for caffeine delivery to the deeper skin layers. It is also aimed to achieve a novel nanotechnology-based cosmeceutical formulation with predetermined quality. Hence both caffeine and argan oil encapsulated semi-solid NLCs were developed by following QbD steps. An artificial neural network (ANN) program was employed to reach optimized formulation with desired critical quality attributes (CQAs). The optimized formulation suggested by the ANN exhibited a particle size of 186.5 nm with a PDI value of 0.208 and the occlusion factor of the optimized formulation reached 50.25% after 12 h. A high level of similarity was obtained between the CQAs predicted by ANN and experimental results for the optimum formulation. The present study concluded that the novel caffeine-loaded semi-solid NLC formulation which also contains argan oil is a promising candidate for local treatment of cellulite and it may possess the measurable skin effect. Moreover; a high-quality nano-cosmeceutical product was obtained with the help of artificial intelligence by following QbD steps for the first time to the best of our knowledge.Item Development of Cyclosporine A Nanosuspension: Cytotoxicity and Permeability on Caco-2 Cell Lines(2021) Celebi, Nevin; 34931593Cyclosporine A is a calcineurin inhibitor and is usually used as an immunosuppressant medication. The main purpose of this study is to develop nanosuspension of polypeptide cyclosporine A by using the wet milling method for oral administration. Cell culture studies were also performed with human intestinal Caco-2 cell lines. Hydroxypropyl methylcellulose and sodium dodecyl sulfate were used as stabilizers in nanosuspension. In vitro characterization studies such as Fourier-transform infrared analysis and morphological imaging with scanning electron microscopy have been carried out with obtained cyclosporine A nanosuspension. The particle size, particle size distribution, and zeta potential values of the nanosuspension were measured approximately 400 nm, 0.4, and -25 mV, respectively. The solubility of cyclosporine A was increased 4.5 times in nanosuspension compared to the coarse cyclosporine A powder. As a result of cytotoxicity studies conducted with different concentrations, it was decided to conduct permeability studies at a dose equivalent to 150 mu g/mL cyclosporine A. Permeation studies have shown that the nanosuspension increases cyclosporine A transport by 5 and 1.5 times, respectively, compared to coarse powder and commercial product.Item Electrochemical Detection of Antioxidant Activities of 4-Indolyl-5-Oxo-6,6 (Or 7,7)-Dimethyl-1,4,5,6,7,8-Hexahydroquinoline Derivatives(2021) Suslu, Incilay; Kablan, Sevilay Erdogan; Safak, Cihat; Simsek, RahimeAntioxidants used in different medical and industrial fields in order to prevent and delay oxidative stress. They play a crucial role in the protecting biological systems against many diseases. 1,4-dihydropyridines are known as calcium channel modulators. Electrochemical techniques are simple, cheap and fast detection techniques and require small amounts of sample, so they offer advantages over commonly used analytical methods. Voltammetric methods have been applied to investigated the antioxidant activity of compounds in different fields. The proposed work is aimed at examining the electrochemical behavior of the 1,4-dihydropyridines by differential pulse voltammetry and hence the assessment of its antioxidant activity from the cathodic reduction peak of oxygen values. The peak current due to oxygen reduction was found to be proportional to the 1,4-dihydropyridines concentration of 0.1 - 0.5 mg/mL. The coefficient of antioxidant activity of 1,4-dihydropyridine derivatives were calculated and compared each other. Nifedipine used as a reference drug that is known as the calcium channel modulator and it is used to compare the antioxidant activities of 1,4-dihydropyridine-derived compounds.Item Estimation of Low-Density Lipoprotein Cholesterol Concentration Using Machine Learning(2021) Cubukcu, Hikmet Can; Topcu, Deniz İlhan; 0000-0002-1219-6368; 34635916; E-3717-2019Objective Low-density lipoprotein cholesterol (LDL-C) can be estimated using the Friedewald and Martin-Hopkins formulas. We developed LDL-C prediction models using multiple machine learning methods and investigated the validity of the new models along with the former formulas. Methods Laboratory data (n = 59,415) on measured LDL-C, high-density lipoprotein cholesterol, triglycerides (TG), and total cholesterol were partitioned into training and test data sets. Linear regression, gradient-boosted trees, and artificial neural network (ANN) models were formed based on the training data. Paired-group comparisons were performed using a t-test and the Wilcoxon signed-rank test. We considered P values .2 to be statistically significant. Results For TG >= 177 mg/dL, the Friedewald formula underestimated and the Martin-Hopkins formula overestimated the LDL-C (P <.001), which was more significant for LDL-C <70 mg/dL. The linear regression, gradient-boosted trees, and ANN models outperformed the aforementioned formulas for TG >= 177 mg/dL and LDL-C <70 mg/dL based on a comparison with a homogeneous assay (P >.001 vs. P <.001) and classification accuracy. Conclusion Linear regression, gradient-boosted trees, and ANN models offer more accurate alternatives to the aforementioned formulas, especially for TG 177 to 399 mg/dL and LDL-C <70 mg/dL.Item Evaluation of the hypoglycemic effect of exendin-4's new oral self-nanoemulsifying system in rats(2021) Celik Tekeli, Merve; Celebi, Nevin; Tekeli, M. Yasin; Aktas, Yesim; 33197556The objective of this study is to develop a new self-nanoemulsifying system containing exendin-4 with or without enzyme inhibitor chymostatin and to evaluate the effects of oral administration of exendin-4 and exendin-4/chymostatin loaded self nanoemulsifying system on plasma exendin-4, plasma insulin, blood glucose levels and to compare with the oral and subcutaneous administration of exendin-4 in non-diabetic and streptozotocin-induced type 2 diabetic rats. Exendin-4 and exendin-4/chymostatin loaded self-nanoemulsifying system containing ethyl oleate as the oil phase, Cremophor EL (R)/Labrasol (R) as the surfactants and propylene glycol as the co-solvent were prepared. The mean droplet size, polydispersity index, zeta potential and viscosity of exendin-4 loaded self-nanoemulsifying system were found as 24.28 +/- 0.43 nm, 0.17 +/- 0.01, -1.28 +/- 3.61 mV, 79.60 +/- 3.30 m.Pas, respectively. The mean droplet size, polydispersity index, zeta potential and viscosity of exendin-4/chymostatin loaded self-nanoemulsifying system were found as 20.25 +/- 0.35 nm, 0.11 +/- 0.02, -1.85 +/- 2.49 mV, 100.02 +/- 7.65 m.Pas, respectively according to our previous study. In the present study, we focused on long-term physical stability studies, pharmacokinetic studies and pharmacodynamic studies of prepared self-nanoemulsifying systems. According to the long-term physical stability data, exendin-4 and exendin-4/chymostatin loaded self-nanoemulsifying systems were found stable both at 5 degrees C +/- 3 degrees C and at 25 degrees C +/- 60% RH for 12 months. Exendin-4 and exendin-4/chymostatin loaded self-nanoemulsifying systems increased AUC and C-max values in non-diabetic rats compared to the oral exendin-4 solution. In diabetic rats, exendin-4/chymostatin loaded self nanoemulsifying systems increased C-max values compared to the exendin-4 solution. Exendin-4/chymostatin loaded self-nanoemulsifying system decreased inter-subject variability compared to commercial Byetta (R). At 30th minute after administration of exendin-4 loaded self-nanoemulsifying system, exendin-4/chymostatin loaded self nanoemulsifying system and Byetta (R), blood glucose levels decreased to 23%, 25%, 29%, respectively. It has been shown that pharmacodynamic response is close to Byetta (R) with exendin-4/chymostatin self-nanoemulsifying system oral administration. In conclusion, a self nanoemulsifying system was found to be a suitable carrier system, and the combination with enzyme inhibitor chymostatin is thought to be promising for oral delivery of exendin-4.Item Comparison of in vitro activities of plazomicin and other aminoglycosides against clinical isolates of Klebsiella pneumoniae and Escherichia coli(2021) Ince, Gizem; Mirza, Hasan Cenk; Guclu, Aylin Uskudar; Gumus, Hale; Erol, Cigdem; Basustaoglu, Ahmet; 0000-0001-9071-9606; 0000-0002-1872-028X; 0000-0002-2535-2534; 0000-0002-8853-3893; 34499728; AAJ-2108-2021; AAU-6196-2020; AAJ-1219-2021; F-1232-2015Objectives: To compare the in vitro activity of plazomicin and two older aminoglycosides (gentamicin and amikacin) against 180 isolates of Escherichia coli and Klebsiella pneumoniae, including subsets of 60 non-ESBL-producing, 60 ESBL-producing and 60 carbapenem-resistant (46 carrying bla(OXA-48), 11 carrying bla(NDM) and 3 carrying bla(OXA-48) and bla(NDM)) strains. Methods: MICs of plazomicin, gentamicin and amikacin were determined by a gradient diffusion method. Gentamicin and amikacin MICs were interpreted according to CLSI criteria and EUCAST breakpoint tables. Plazomicin MICs were interpreted using FDA-defined breakpoints. Results: All non-ESBL-producing and ESBL-producing isolates were susceptible to plazomicin. The plazomicin susceptibility rate (71.7%) in carbapenem-resistant isolates was significantly higher than those observed for gentamicin (45%) and amikacin (56.7% and 51.7% according to CLSI and EUCAST breakpoints, respectively). Gentamicin, amikacin and plazomicin susceptibility rates (35.6% for gentamicin; 44.4% and 37.8% for amikacin according to CLSI and EUCAST breakpoints, respectively; 64.4% for plazomicin) in carbapenem-resistant K. pneumoniae were significantly lower than those observed for carbapenem-resistant E. coli isolates (73.3% for gentamicin; 93.3% for amikacin and plazomicin). Gentamicin, amikacin and plazomicin susceptibility rates for bla(NDM)-positive isolates were lower than those observed for bla(OXA-48)-positive isolates, but differences were not statistically significant. Among the isolates that were non-susceptible to both gentamicin and amikacin, the plazomicin susceptibility rate was less than 30%. Conclusions: Although plazomicin showed excellent in vitro activity against carbapenem-susceptible isolates, the plazomicin resistance rate increased to 35.6% among carbapenem-resistant K. pneumoniae and further increased to 45.5% among bla(NDM)-positive isolates.Item Propensity Score and Desirability of Outcome Ranking Analysis of Ertapenem for Treatment of Nonsevere Bacteremic Urinary Tract Infections Due to Extended-Spectrum-Beta-Lactamase-Producing Enterobacterales in Kidney Transplant Recipients(2021) Arslan, Hande; 0000-0002-5708-7915; 34370578; ABG-7034-2021There are scarce data on the efficacy of ertapenem in the treatment of bacteremia due to extended-spectrum-beta-lactamase (ESBL)-producing Enterobacterales (ESBL-E) in kidney transplant (KT) recipients. We evaluated the association between treatment with ertapenem or meropenem and clinical cure in KT recipients with nonsevere bacteremic urinary tract infections (B-UTI) caused by ESBL-E. We performed a registered, retrospective, international (29 centers in 14 countries) cohort study (INCREMENT-SOT, NCT02852902). The association between targeted therapy with ertapenem versus meropenem and clinical cure at day 14 (the principal outcome) was studied by logistic regression. Propensity score matching and desirability of outcome ranking (DOOR) analyses were also performed. A total of 201 patients were included; only 1 patient (treated with meropenem) in the cohort died. Clinical cure at day 14 was reached in 45/100 (45%) and 51/101 (50.5%) of patients treated with ertapenem and meropenem, respectively (adjusted OR 1.29; 95% CI 0.51 to 3.22; P = 0.76); the propensity score-matched cohort included 55 pairs (adjusted OR for clinical cure at day 14, 1.18; 95% CI 0.43 to 3.29; P = 0.74). In this cohort, the proportion of cases treated with ertapenem with better DOOR than with meropenem was 49.7% (95% CI, 40.4 to 59.1%) when hospital stay was considered. It ranged from 59 to 67% in different scenarios of a modified (weights-based) DOOR sensitivity analysis when potential ecological advantage or cost was considered in addition to outcome. In conclusion, targeted therapy with ertapenem appears as effective as meropenem to treat nonsevere B-UTI due to ESBL-E in KT recipients and may have some advantages.Item Oral self-nanoemulsifying formulation of GLP-1 agonist peptide exendin-4: development, characterization and permeability assesment on Caco-2 cell monolayer(2021) Celebi, Nevin; Tekeli, Merve Celik; Aktas, Yesim; https://orcid.org/0000-0002-6402-5042; https://orcid.org/0000-0002-5234-8434; 33398527; AAL-6931-2021The objective of this study was to prepare a stable self-nanoemulsifying formulation of exendin-4, which is an antidiabetic peptide. As exendin-4 is commercially available only in subcutaneous form, several attempts have been made to discover an effective oral formulation. Self-nanoemulsifying drug delivery systems are known to be suitable carriers for the oral administration of peptide drugs. Various ratios of oil, surfactant, and co-surfactant mixtures were used to determine the area in the pseudoternary phase diagram for clear nanoemulsion. The Design of Experiment approach was used for the optimization of the formulation. Blank self-nanoemulsifying formulations containing ethyl oleate as oil phase, Cremophor EL(R), and Labrasol(R) as surfactant, absolute ethanol, and propylene glycol as co-solvent in various proportions were approximately 18-50 nm, 0.08-0.204 and - 3 to - 23 mV in droplet size, polydispersity index, and zeta potential, respectively. When all formulations were compared by statistical analysis, five of them with smaller droplet sizes were selected for further studies. The physical stability test was performed for 1 month at 5 degrees C +/- 3 degrees C and 25 degrees C +/- 2 degrees C/60% RH +/- 5% RH storage conditions. As a result of the characterization and physical stability test results, ethyl oleate: Cremophor EL(R):absolute ethanol (30:52.5:17.5) formulation and four formulations containing ethyl oleate: Cremophor EL(R):Labrasol(R):propylene glycol:absolute ethanol at varying concentrations were considered for peptide encapsulation efficiency. Formulation having the highest encapsulation efficiency of exendin-4 containing ethyl oleate: Cremophor EL(R):Labrasol(R):propylene glycole:absolute ethanol (15:42.5:21.25:15.94:5.31) was selected for in vitro Caco-2 intestinal permeability study. The permeabiliy coefficient was increased by 1.5-folds by exendin-4-loaded self-nanoemulsifying formulation as compared to the exendin-4 solution. It can be concluded that intestinal permeability has been improved by self-nanoemulsifying formulation.Item Detection of COVID-19 by Machine Learning Using Routine Laboratory Tests(2021) Cubukcu, Hikmet Can; Topcu, Deniz Ilhan; Bayraktar, Nilufer; Gulsen, Murat; Sari, Nuran; Arslan, Ayse Hande; 0000-0002-1219-6368; 0000-0002-7886-3688; 34791032; E-3717-2019; Y-8758-2018Objectives The present study aimed to develop a clinical decision support tool to assist coronavirus disease 2019 (COVID-19) diagnoses with machine learning (ML) models using routine laboratory test results. Methods We developed ML models using laboratory data (n = 1,391) composed of six clinical chemistry (CC) results, 14 CBC parameter results, and results of a severe acute respiratory syndrome coronavirus 2 real-time reverse transcription-polymerase chain reaction as a gold standard method. Four ML algorithms, including random forest (RF), gradient boosting (XGBoost), support vector machine (SVM), and logistic regression, were used to build eight ML models using CBC and a combination of CC and CBC parameters. Performance evaluation was conducted on the test data set and external validation data set from Brazil. Results The accuracy values of all models ranged from 74% to 91%. The RF model trained from CC and CBC analytes showed the best performance on the present study's data set (accuracy, 85.3%; sensitivity, 79.6%; specificity, 91.2%). The RF model trained from only CBC parameters detected COVID-19 cases with 82.8% accuracy. The best performance on the external validation data set belonged to the SVM model trained from CC and CBC parameters (accuracy, 91.18%; sensitivity, 100%; specificity, 84.21%). Conclusions ML models presented in this study can be used as clinical decision support tools to contribute to physicians' clinical judgment for COVID-19 diagnoses.Item Unpredictable adverse effects of herbal products(2021) Basaran, Nursen; Pasli, Duygu; Basaran, A. Ahmet; 34896186Herbal products are being increasingly used all over the world for preventive and therapeutic purposes because of the belief of their safety. They have become an important part of health care system in many countries since they can easily be purchased in the health food stores or online. However, the lack of sufficient study on their efficacy and toxicity, inadequate controls of their availability, reduce their safety. Unlike conventional drugs, herbal products are not regulated for purity and potency. Herbal products contain substances which can induce or inhibit enzymes that take part in drug metabolism. Therefore the concurrent use of drugs with some medicinal plants can cause serious adverse effects and can also decrease the efficacy of the therapy. Particularly, drugs with narrow therapeutic index and plants which can affect drug metabolizing enzymes when used together, may lead to unpredictable adverse reactions. Impurities, contaminants and adulterants found in the herbal products, are the most common malpractises in herbal raw-material trade. In this review the unpredictable adverse effects of herbal products due to their possible interactions with drugs and also due to the adulteration and contamination with prohibited chemicals will be discussed in detail.Item Enhanced Dermal Delivery of Flurbiprofen Nanosuspension Based Gel: Development and Ex Vivo Permeation, Pharmacokinetic Evaluations(2021) Oktay, Ayse Nur; Ilbasmis Tamer, Sibel; Uludag, Orhan; Celebi, Nevin; 34086139Purpose The objective of this study was to optimize the Flurbiprofen (FB) nanosuspension (NS) based gel and to investigate the in vitro release, ex vivo permeation, the plasma concentration-time profile and pharmacokinetic parameters. Methods FB-NSs were developed using the wet milling process with the Design of Experiment (DoE) approach. The optimum FB-NS was characterized on the basis of SEM, DSC, XRPD, solubility and permeation studies. The dermal gel was prepared by incorporating FB-NS into HPMC gel. Then the in-vitro release, ex vivo permeation studies were performed, and pharmacokinetic studies were evaluated on rats. Results The particle size, polydispersity index and zeta potential values of optimum NS were determined as 237.7 +/- 6.8 nm, 0.133 +/- 0.030 and - 30.4 +/- 0.7 mV, respectively. By means of the surfactant content and nanosized particles of the nanosuspension, the solubility of FB was increased about 7-fold. The percentage permeated amount of FB from FB-NS gel (8.40%) was also found to be higher than the physical mixture (5.25%) and coarse suspension (reference) (2.08%) gels. The pharmacokinetic studies showed that the C-max of FB-NS gel was 2.5 times higher than the reference gel, while AUC(0-24) was 2.96 times higher. Conclusion FB-NSs were successfully prepared with a wet milling method and optimized with the DoE approach. The optimized FB nanosuspension gel provided better permeation and pharmacokinetic performance compared to FB coarse suspension gel.Item In Vitro Caco-2 Cell Permeability Studies of Ziprasidone Hydrochloride Monohydrate Nanocrystals(2021) Karakucuk, Alptug; Tashan, Emine; Ozturk, Naile; Celebi, Nevin; 0000-0002-6402-5042; 33902264Objectives: The current study focused on the evaluation of the cytotoxic effect and permeability of ziprasidone hydrochloride monohydrate (ZHM) nanocrystals on Caco-2 cells. Materials and Methods: ZHM nanocrystals were prepared by the microfluidization method in the presence of polyvinylpyrrolidone as a stabilizer. Particle size (PS), particle size distribution (PDI), and zeta potential (ZP) values were measured in characterization studies. In vitro cytotoxic effects of ZHM nanocrystals were investigated using the 3-(4,5-dimetylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test. Caco-2 transport studies were conducted with formulations of ZHM coarse powder and nanocrystals. Results: Nanocrystals were obtained with 400-600 nm PS, 0.1-0.4 PDI, and >20 mV ZP values. The cell viability remained 100% for all sample groups. The permeability value of ZHM nanocrystals through Caco-2 cells increased 2.3-fold in comparison with ZHM coarse powder. Cumulative drug transport also increased at the end of the sampling period. Conclusion: Nanocrystal technology helps to increase the permeability of drug particles by increasing the saturation solubility.Item Etodolac nanosuspension based gel for enhanced dermal delivery: in vitro and in vivo evaluation(2021) Celebi, Nevin; 0000-0002-6402-5042; 33752553Aim The objective of this study was to develop dermal nanosuspension (NS) based gel formulation of etodolac (ETD). Methods Etodolac nanosuspension (ETD-NS) was prepared by wet milling method and dispersed in hydroxypropyl methylcellulose (NS-HPMC) or hydroxyethyl cellulose (NS-HEC) gels. Rheologic and mechanical properties were investigated. In vitro and ex vivo permeability studies were performed. Topical anti-inflammatory and analgesic activity were evaluated in regard to carrageenan-induced inflammatory paw oedema and radiant heat tail-flick method, respectively. Results The ETD-NS with approximately 190 nm particle size (PS), 0.16 polydispersity index (PDI), and -15 mV zeta potential (ZP) values were obtained. The work of bioadhesion values of NS-HEC and NS-HPMC gels were 0.229 mJ/cm(2) for both gels. Dermal permeation of ETD from NS-HEC gel (7.18%) was found significantly higher than the NS-HPMC gel (4.56%). Enhanced anti-inflammatory and analgesic activity of NS-HEC gels were observed in comparison with micronised ETD. Conclusions ETD-NS based gel formulation is promising for topical delivery of ETD.
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