Bulunan: 16 Adet 0.001 sn
Koleksiyon [4]
Tam Metin [1]
Yazar [20]
Yayın Türü [1]
Konu Başlıkları [20]
Yayın Tarihi [1]
Dergi Adı [14]
Yayıncı [1]
Dil [1]
Yazar Departmanı [1]
Role of modification route for zinc oxide nanoparticles on protein structure and their effects on glioblastoma cells

Altunbek, M. | Keleştemur, S. | Baran, G. | Çulha, Mustafa

Article | 2018 | International Journal of Biological Macromolecules118 , pp.271 - 278

Zinc oxide nanoparticles (ZnO) are presented as potential cancer therapeutic agent based on their surface properties. In this study, the most abundant blood proteins, albumin, fibrinogen and apo-transferrin, were covalently bound (c-ZnO NPs) and nonspecifically adsorbed (n-ZnO NPs) onto ZnO NPs to evaluate the role of modification route on protein structure and their effects on glioblastoma cells. The success of modification and structures of proteins on ZnO NPs were characterized with FT-IR. It was found that non-covalent interaction significantly damaged the secondary structure of proteins compared to those covalently attached to . . .the ZnO nanoparticle. The effects of modified ZnO NPs were investigated by evaluating viability, cycle, and death mechanisms of glioblastoma (U373) cells. n-ZnO NPs were found more toxic compared to the pristine and c-ZnO NPs. However, c-ZnO NPs with albumin and apo-transferrin both perturbed the cell cycle function, and decreased the necrotic cell death rate of U373 cells below toxic concentration, suggesting their potential curative effect on glioblastoma cells. © 2018 Elsevier B.V Daha fazlası Daha az

An appointment scheduling framework to balance the production of blood units from donation

Baş, S. | Carello, G. | Lanzarone, E. | Yalçındağ, S.

Article | 2018 | European Journal of Operational Research265 ( 3 ) , pp.1124 - 1143

Blood is fundamental in several care treatments and surgeries, and plays a crucial role in the health care system. It is a limited resource, as it can be produced only by donors and its shelf life is short; thus, the blood donation (BD) system aims at providing adequate supply of blood units to transfusion centers and hospitals. An effective collection of blood units from donors is fundamental for adequately feeding the entire BD system and optimizing blood usage. However, despite its relevance, donation scheduling is only marginally addressed in the literature. In this paper we consider the Blood Donation Appointment Scheduling (BD . . .AS) problem, aiming at balancing the production of the different blood types among days in order to provide a quite constant feeding of blood units to the BD system. We propose a framework for the appointment reservation that accounts for both booked donors and donors arriving without a reservation. It consists of an offline Mixed Integer Linear Programming (MILP) model for preallocating time slots to blood types, and an online prioritization policy to assign a preallocated slot when the donor calls to make the reservation. © 2017 Elsevier B.V Daha fazlası Daha az

Enzyme inhibitory and antioxidant activities of Nerium oleander L. flower extracts and activity guided isolation of the active components

Atay Balkan, İ. | Doğan, H.T. | Zengin, G. | Colak, N. | Ayaz, F.A. | Gören, A.C. | Yeşilada, E.

Article | 2018 | Industrial Crops and Products112 , pp.24 - 31

Oleander (Nerium oleander L., fam: Apocynaceae) is an evergreen shrub. Although it is known to be poisonous to humans, a large number of utilizations in folk medicine have been reported against diabetes, rheumatic pain and skin diseases. The present study aimed to investigate the cholinesterase inhibitory activities of oleander flower extracts and to isolate the active components responsible for the activity. The antidiabetic and skin care effects were also determined on some key enzymes (?-glucosidase, ?-amylase, tyrosinase). The flower extracts obtained with aqueous, polar and apolar organic solvents were evaluated for their pheno . . .lic contents and antioxidant capacities. The enzyme inhibitory activities (cholinesterase, ?-glucosidase, ?-amylase and tyrosinase) were examined by microtiter plate assays. Antioxidant properties were evaluated by DPPH, FRAP and CUPRAC assays. Total phenolic and flavonoid contents were determined using the Folin-Ciocalteu reagent and aluminum chloride, respectively. The structures of the isolates were elucidated by NMR and MS experiments.In the present study, cholinesterase inhibitory activity of the EtOH extract of the olaender flowers was investigated and ß-sitosterol and oleanolic acid were isolated as the active components. The less polar extracts (n-hexane) exerted better cholinesterase and ?-amylase inhibitory activities than those of the more polar extracts (R-H2O, EtOAc) which had better ?-glucosidase and tyrosinase activities. The highest antioxidant capacity values were obtained from EtOAc and EtOH extracts. The EtOH extract was found to contain the highest levels of total phenolic and flavonoid contents. The results suggest that the flowers of oleander could be a potential source for high value phytochemicals for developing novel drug leads. © 2017 Elsevier B.V Daha fazlası Daha az

Bioactivity-guided isolation of cytotoxic secondary metabolites from the roots of Glycyrrhiza glabra and elucidation of their mechanisms of action

Çevik, D. | Burçin Yılmazgöz, Ş. | Kan, Y. | Akhan Güzelcan, E. | Durmaz, I. | Çetin-Atalay, R. | Kırmızıbekmez, H.

Article | 2018 | Industrial Crops and Products124 , pp.389 - 396

Licorice (Glycyrrhiza glabra L.) is one of the most widely used plants worldwide for its various pharmacological activities. The aim of this study was to isolate the potential cytotoxic secondary metabolites from the MeOH extract prepared from the roots of Glycyrrhiza glabra through bioactivity-guided isolation procedure and to elucidate their mechanisms of action. The crude MeOH extract as well as CHCl3 and EtOAc subextracts significantly inhibited cell proliferation on hepatocelullar (Huh7), breast (MCF7) and colorectal (HCT116) cancer cell lines with IC50 values in the range of 5.6 to 33.6 µg/mL. Chromatographic seperations of th . . .e CHCl3 and EtOAc subextracts yielded 13 secondary metabolites. Structures were characterized based on NMR and MS data. Amongst isolates, glabridin (1), 4'-O-methylglabridin (2), ß-amyrin (3), kanzonol U (4), glabrene (7) and tetrahydroxymethoxychalcone (10) were established to be responsible for in vitro cytotoxicity of G. glabra, exerting the best activity particularly against Huh7 cells. Further mechanistic studies demonstrated that 2 and 7 induced caspase-dependent apoptosis by increasing cytochrome C release and subsequently cleaved caspase-9 level in Huh7 cells. Moreover, both compounds decreased pRb and p21 levels and thus induced the accumulation of Huh-7 cells in subG1 and G2/M phases. Compound 10 which displayed the most potent activity in Hoechst staining and cell cycle assays through G2/M arrest, caused cell death by apoptosis in Huh7 cells. © 2018 Elsevier B.V Daha fazlası Daha az

Effects of individual and combined effects of salinity and drought on physiological, nutritional and biochemical properties of cabbage (Brassica oleracea var. capitata)

Sahin, U. | Ekinci, M. | Ors, S. | Turan, M. | Yildiz, S. | Yildirim, E.

Article | 2018 | Scientia Horticulturae240 , pp.196 - 204

To understand the effects of salt and drought stress factors on the growth, physiological and biochemical responses of cabbage (Brassica oleracea var. capitata), a greenhouse experiment was conducted with different levels of salinity (S0: tap water, S1: tap water containing extra 75 mM dose of NaCl, and S2: tap water containing extra 150 mM dose of NaCl), irrigation quantity (W0: Full-irrigation, W1: irrigation with 80% of the W0, and W2: irrigation with 60% of the W0), and their combinations. The results showed that antioxidant activity, proline and sucrose contents increased under both salinity and drought stress as well as their . . .combination. Moreover, oxidative damage indicating parameters such as electrical leakage (EL), malondialdehyde (MDA), and hydrogen peroxide (H2O2) increased as well. Increased level of salinity and drought stress caused a decrease in chlorophyll content (SPAD), leaf relative water content (LRWC), stomatal conductance (gs), net photosynthetic activity (An), intercellular CO2 content (Ci) and transpiration rate (Tr). We observed that proline and sucrose contents could not stimulate the growth of plant under increased levels of salinity and drought stress. Individual drought and salt stress conditions have negatively affected plant growth including the shoot, root fresh and dry weights when applied separately. On the other hand, the combination of drought and salinity enhanced the adverse effects of each stress factor. © 2018 Elsevier B.V Daha fazlası Daha az

Influence of multidrug resistant organisms on the outcome of diabetic foot infection

Saltoglu, N. | Ergonul, O. | Tulek, N. | Yemisen, M. | Kadanali, A. | Karagoz, G. | Diabetic Foot Infections Study, Group

Article | 2018 | International Journal of Infectious Diseases70 , pp.10 - 14

Objectives: We described the clinical outcomes of the diabetic patients who had foot infections with multidrug resistant organisms. Methods: We included the patients with diabetic foot infections (DFI) from 19 centers, between May 2011 and December 2015. Infection was defined according to IDSA DFI guidelines. Patients with severe infection, complicated moderate infection were hospitalized. The patients were followed-up for 6 months after discharge. Results: In total, 791 patients with DFI were included, 531(67%) were male, median age was 62 (19–90). Severe infection was diagnosed in 85 (11%) patients. Osteomyelitis was diagnosed in . . .291(36.8%) patients. 536 microorganisms were isolated, the most common microorganisms were S. aureus (20%), P. aeruginosa (19%) and E. coli (12%). Methicillin resistance (MR) rate among Staphylococcus aureus isolates was 31%. Multidrug resistant bacteria were detected in 21% of P. aeruginosa isolates. ESBL (+) Gram negative bacteria (GNB) was detected in 38% of E. coli and Klebsiella isolates. Sixty three patients (8%) were re-hospitalized. Of the 791 patiens, 127 (16%) had major amputation, and 24 (3%) patients died. In multivariate analysis, significant predictors for fatality were; dialysis (OR: 8.3, CI: 1.82–38.15, p = 0.006), isolation of Klebsiella spp. (OR:7.7, CI: 1.24–47.96, p = 0.028), and chronic heart failure (OR: 3, CI: 1.01–9.04, p = 0.05). MR Staphylococcus was detected in 21% of the rehospitalized patients, as the most common microorganism (p < 0.001). Conclusion: Among rehospitalized patients, methicillin resistant Staphylococcus infections was detected as the most common agent, and Klebsiella spp. infections were found to be significantly associated with fatality. © 2018 The Author Daha fazlası Daha az

A design achieved by coaxial electrospinning of polysulfone and sulfonated polysulfone as a core-shell structure to optimize mechanical strength and hemocompatibility

Aydemir Sezer, U. | Ozturk, K. | Aru, B. | Yanıkkaya Demirel, G. | Sezer, S.

Article | 2018 | Surfaces and Interfaces10 , pp.176 - 187

Hemocompatibility is an essential quality for blood contacting materials in clinical applications. Blood contacting biomaterials should not initiate blood coagulation while performing their functions. There has been a long-standing tendency to use heparinized or heparin-like structures in the materials for blood contacting sites. However, such structures might lead to limitations in mechanical properties due to the breakage of bonds on the backbone or phase separation in case of blending. Moreover, the methods including plasma and grafting synthesis are restricted due to their high costs and difficulties in industrial applications. . . .In this study, we investigated a core-shell electrospun structure having polysulfone in the core part and sulfonated polysulfone in the shell part. We proved that this combination is more hemocompatible than polysulfone itself and offers a more stable mechanical structure than the sulfonated polysulfone itself does. Chemical and physical characterizations indicated that the sulfonated polysulfone covered the core structure of the polysulfone properly. We conducted in vitro studies in order to determine the blood compatibility and cytotoxicity of the core-shell material. The results indicated that the membranes were hemocompatible and mechanically strong; which makes it possible to use them in blood contacting applications. © 2017 Elsevier B.V Daha fazlası Daha az

Simultaneous miRNA and mRNA transcriptome profiling of glioblastoma samples reveals a novel set of OncomiR candidates and their target genes

Gulluoglu, S. | Tuysuz, E.C. | Sahin, M. | Kuskucu, A. | Kaan Yaltirik, C. | Ture, U. | Dalan, A.B.

Article | 2018 | Brain Research1700 , pp.199 - 210

Although glioblastomas are common, there remains a need to elucidate the underlying mechanisms behind their initiation and progression and identify molecular pathways for improving treatment. In this study, sixteen fresh-frozen glioblastoma samples and seven samples of healthy brain tissues were analyzed with miRNA and whole transcriptome microarray chips. Candidate miRNAs and mRNAs were selected to validate expression in fifty patient samples in total with the criteria of abundance, relevance and prediction scores. miRNA and target mRNA relationships were assessed by inhibiting selected miRNAs in glioblastoma cells. Functional test . . .s have been conducted in order to see the effects of miRNAs on invasion, migration and apoptosis of GBM cells. Analyses were carried out to determine correlations between selected molecules and clinicopathological features. 1332 genes and 319 miRNAs were found to be dysregulated by the microarrays. The results were combined and analyzed with Transcriptome Analysis Console 3 software and the DAVID online database. Primary differential pathways included Ras, HIF-1, MAPK signaling and cell adhesion. OncomiR candidates 21-5p, 92b-3p, 182-5p and 339-5p for glioblastoma negatively correlated with notable mRNA targets both in tissues and in in vitro experiments. miR-21-5p and miR-339-5p significantly affected migration, invasion and apoptosis of GBM cells in vitro. Significant correlations with overall survival, tumor volume, recurrence and age at diagnosis were discovered. In this article we present valuable integrated microarray analysis of glioblastoma samples regarding miRNA and gene-expression levels. Notable biomarkers and miRNA-mRNA interactions have been identified, some of which correlated with clinicopathological features in our cohort. © 201 Daha fazlası Daha az

P 141 - What is the effect on the popliteal angle of femoral anteversion increased in healthy individuals?

Sardoğan, C. | Akalan, N.E. | Bilgili, F. | Sert, R. | Leblebici, G. | Önerge, K. | Evrendilek, H.

Article | 2018 | Gait and Posture65 , pp.470 - 472

[No abstract available]

Assessment of potential bioavailability of major phenolic compounds in Lavandula stoechas L. ssp. stoechas

Celep, E. | Akyüz, S. | İnan, Y. | Yeşilada, Erdem

Article | 2018 | Industrial Crops and Products118 , pp.111 - 117

Despite the countless number of studies on phenolic compounds from herbal resources and their related bioactivities, their bioavailability factors are generally disregarded. The present study was performed in order to assess the potential bioavailability of major phenolics found in the aerial parts of Lavandula stoechas L. ssp. stoechas. To that end, a simulated human digestion method consisting of both gastric and intestinal phases was conducted. The total phenolic, phenolic acid and flavonoid contents were appraised together with high performance thin layer chromatography analysis of the two phenolic acids (rosmarinic acid and chl . . .orogenic acid) and two flavone glycosides (apigenin 7-glucoside and luteolin-7-O-ß-glucoside). On the other hand, antioxidant potentials of the samples were investigated using assays with different mechanisms such as free radical scavenging tests and metal-related activity tests. According to the results, flavone glycosides had lower bioavailability than phenolic acids, and antioxidant activities were altered due to in vitro gastrointestinal digestion. © 2018 Elsevier B.V Daha fazlası Daha az

A solution to the classification problem with cellular automata

Uzun, A.O. | Usta, T. | Dündar, E.B. | Korkmaz, E.E.

Article | 2018 | Pattern Recognition Letters116 , pp.114 - 120

Classification is the task of labeling data instances by using a trained system. The data instances consist of various attributes and in order to train the system, a set of already labeled data is utilized. After the training process, success rate of the system is determined with separate test sets. Various machine learning algorithms are proposed for the solution of the problem. On the other side, Cellular Automata (CA) provide a computational model consisting of cells interacting with each other based on some predetermined rules. In this study, a new approach is proposed for the classification problem based on CA. The method maps . . .the data instances in the training data set to cells of an automaton based on the attribute values. When a CA cell receives a data instance, this cell and its neighbors are heated based on a heat transfer function. A separate automaton is heated for each class in the data set and hence a characteristic heat map is obtained for each class at the end of the procedure. Then new instances are classified by using these heat maps. The success rate of the algorithm is compared with the results of other known classification algorithms in the experiments carried out. © 2018 Elsevier B.V Daha fazlası Daha az

Neighborhood resolved fiber orientation distributions (NRFOD) in automatic labeling of white matter fiber pathways

Ugurlu, D. | Firat, Z. | Türe, U. | Unal, G.

Article | 2018 | Medical Image Analysis46 , pp.130 - 145

Accurate digital representation of major white matter bundles in the brain is an important goal in neuroscience image computing since the representations can be used for surgical planning, intra-patient longitudinal analysis and inter-subject population connectivity studies. Reconstructing desired fiber bundles generally involves manual selection of regions of interest by an expert, which is subject to user bias and fatigue, hence an automation is desirable. To that end, we first present a novel anatomical representation based on Neighborhood Resolved Fiber Orientation Distributions (NRFOD) along the fibers. The resolved fiber orien . . .tations are obtained by generalized q-sampling imaging (GQI) and a subsequent diffusion decomposition method. A fiber-to-fiber distance measure between the proposed fiber representations is then used in a density-based clustering framework to select the clusters corresponding to the major pathways of interest. In addition, neuroanatomical priors are utilized to constrain the set of candidate fibers before density-based clustering. The proposed fiber clustering approach is exemplified on automation of the reconstruction of the major fiber pathways in the brainstem: corticospinal tract (CST); medial lemniscus (ML); middle cerebellar peduncle (MCP); inferior cerebellar peduncle (ICP); superior cerebellar peduncle (SCP). Experimental results on Human Connectome Project (HCP)’s publicly available “WU-Minn 500 Subjects + MEG2 dataset” and expert evaluations demonstrate the potential of the proposed fiber clustering method in brainstem white matter structure analysis. © 201 Daha fazlası Daha az

6698 sayılı Kişisel Verilerin Korunması Kanunu kapsamında yükümlülüklerimiz ve çerez politikamız hakkında bilgi sahibi olmak için alttaki bağlantıyı kullanabilirsiniz.

Bu site altında yer alan tüm kaynaklar Creative Commons Alıntı-GayriTicari-Türetilemez 4.0 Uluslararası Lisansı ile lisanslanmıştır.