219 research outputs found
Seeking high-quality digital content for children in Turkey
No full textWhat kind of digital content is available for children in Turkey? How are Turkish parents deciding rules about screen time and tablet use? What do children use tablets for? Burcu Izci and colleagues compare young children’s tablet use in Turkey and the US, and also the extent to which parents limit children’s access to tablet devices. Burcu Izci and Yasin Yalcin are PhD candidates at Florida State University (USA); Tugba Bahcekapili is a PhD candidate at the Middle East Technical University (Turkey) and a research assistant at the Karadeniz Technical University (Turkey); and Dr Ithel Jones is a professor at Florida State University
EFFECT OF GRAPE SEED FLOUR ON THE PHENOLIC PROFILE, ANTIOXIDANT CAPACITY AND SENSORY PROPERTIES OF MUFFINS
No full textGok, Ilkay/0000-0002-4871-8981In the study the grape seed flour (GSF) at 7.5% and 15% ratio was blended with wheat flour (W), siyez wheat flour (S) and oat flour (OAT) separately in muffin recipe. The total flavonoid content, total antioxidant capacity, phenolic profile using HPLC-PDA and sensory properties of prepared muffins were determined. Total flavonoid contents of each three muffin were increased significantly (p<0.05) by addition of grape seed flour. Besides, the muffins with OAT had higher total flavonoid content and total antioxidant capacity values than S and W samples. Identified ten phenolic compounds were o-coumaric acid, caffeic acid, gallic acid, phlorizin, kaempherol, transresveratrol, (-)-epicatechin, t- cinnamic acid, (+)-catechin and epigallocatechin gallate. W15 muffin was mostly liked, following with S15 and OAT15 according to crust color, odor, and crumbliness characteristics. The GSF used in muffin formulations up to 15% increased nutritional quality and functional properties without adverse effect on sensory quality.Istanbul Okan UniversityThis is a multidisciplinary MSc. thesis belonging to Elif Yalcin with advisor Ilkay Gok and co-advisor Tugba Ozdal supported by Istanbul Okan University
Latest updates on chronic delta hepatitis
No full textThe hepatitis D virus was shown for the first time in 1977 by Rizzetto and friends. The HDV genome and the cloning of sequence were made in 1986. HDV is the first animal virus with circular RNA genome which is seen only in plant viruses. HDV is an RNA virus with the known smallest viral genome in animal viruses. It is classified as Deltavirus genius depending on the type of virus by ICTV in 1996. HDV is classified as the sole example of delta virus in this genus. Chronic delta hepatitis is the least common form of chronic viral hepatitis due to hepatotropic viruses. In contrast, the virus is highly pathogenic and can cause serious consequences. Today, prevalance of delta hepatitis has been shown to decrease. However, the delta hepatitis continues to be an important health problem in some parts of the world. In our country, especially in Eastern and Southeastern Anatolia, hepatitis D is a serious and important health problem and still maintains its importance as a health problem. In Turkey, still there is a significant number of patients with HDV infection despite a documented decrease in HDV infection. The recommended treatment for chronic HDV infection in the current guidelines is the treatment with peginterferon alfa given once a week for 48 weeks. Treatment is indicated for patients who has compensated disease with active infection. In patients with advanced form of disease, the expected benefits of the peginterferon must be well balanced against the potential side effects and low response rate. An oral antiviral can be recommended in patients who has high levels of serum HBV DNA. In contrast, the control of HBV infecion does not seem to change the natural history of HDV related disease
Why gastric perforation occurs in patients with isolated esophageal atresia: more vulnerable stomach?
No full textAcer T, Karnak I, Yalcin S, Senocak ME. Why gastric perforation occurs in patients with isolated esophageal atresia: more vulnerable stomach? Turk J Pediatr 2012; 54: 312-316
4-Thiazolidinone Derivatives as MMP Inhibitors in Tissue Damage: Synthesis, Biological Evaluation and Docking Studies
No full textNine 2-(1,2-benzothiazol-3-yl)-N-(4-oxo-2-phenyl-1,3-thiazolidin-3-yl)propanamides combining a benzisothiazole and 4-thiazolidinone in one framework were designed and synthesized. The aim of the study was to verify their effectiveness to affect the inflammatory/oxidative process in which free oxygen and nitrite (ROS and RNS) radicals, inflammatory mediators, such as nuclear factor κB (NF-κB), and matrix metalloproteinases (MMPs) are involved. Docking studies of all the compounds were performed in order to explore their binding mode at the MMP-9 protein. An appreciable anti-inflammatory/potential wound healing effects of the tested compounds was highlighted. Derivative 23, bearing a 4-carboxyphenyl substituent at C2 of the 4-thiazolidinone ring, exhibited the highest activity, being able to inhibit MMP-9 at nanomolar level(IC50 = 40 nM)
A correlation study of fluorouracil pharmacodynamics with clinical efficacy and toxicity
No full textPurpose: Plasma 5-fluorouracil (5-FU) concentrations vary greatly between individuals who have received standard dosage. Pharmacokinetic adjusted doses have been hypothesized to overcome the possibility of potential toxicity and ineffectiveness related to inappropriate plasma levels of 5-FU. In this study, we prospectively investigated the clinical benefit and toxicity of 5-FU in relation to its pharmacokinetic properties. Methods: Pharmacokinetics, effectiveness, and toxicity of 5-FU were investigated in 101 patients. The 5-FU pharmacokinetics were measured on day 2 of chemotherapy infusions. Clinicodemographic characteristics are outlined. Results: All 101 patients who received adjuvant chemotherapy were alive at the end of a median 45 months of the follow-up period. At least one grade 1 adverse event (AE) was observed in 69.3% of the patients and grade two AEs were observed in 10.1% of the patients. The 5-FU levels ranged between 103 and 4311 mu g/L and area under the curve (AUC) measurements ranged between 4.5 and 189.7 mg min/L. Pharmacokinetic measurements were not significantly correlated with clinical efficacy (log-rank p = 0.21). However, higher AUC levels were positively correlated with toxicity (p = 0.02) and with the severity of adverse events. The risks of mucositis (odds ratio [OR] 1.45; p = 0.042) and neurotoxicity (OR 2.01; p = 0.009) were significantly increased in a logistic regression model. Conclusions: There is no clear evidence that increased plasma levels or pharmacokinetic adjusted doses of 5-FU were related to better efficacy. However, toxicity might be closely associated with increased plasma levels of 5-FU. Toxicities can be deferred via dose adjustments without any expense in efficacy
Antioxidant activity of whey protein fractions isolated by gel exclusion chromatography an protease treatment
No full textWhey proteins were isolated from whey powder by a combination of gel exclusion chromatography and protease (pepsin or trypsin) treatment. Whey solution (6 g/dl) was applied to Sephadex G-200 column chromatography and three fractions were obtained. Gel electrophoresis (SDS-PAGE) was used to identify the fractions; the first one contained immunooglobulins and bovine serum albumin, the second contained P-lactoglobulin and a-lactalbumin whereas the third fraction contained small peptides. We have also subjected the whey filtrate to proteases (pepsin and trypsin). Treatment with proteases showed that P-lactoglobulin can be obtained after hydrolysis of the second fraction with pepsin. When the whey filtrate was treated with pepsin and then applied to Sephadex G-200 column chromatography three fractions were obtained; the first one was bovine serum albumin, the second was beta-lactoglobulin and the third fraction contained small peptides. After trypsin treatment only two fractions were obtained; the first one was serum albumin and the second fraction was an alpha-lactalbumin rich fraction. We have determined the antioxidant activity of the fractions using an assay based on the measurement of superoxide radical scavenging activity. Our results showed that among the three fractions, the first fraction had the highest superoxide radical scavenging activity. Also, protease treatment of the second fraction resulted in an increase in the antioxidant activity. (c) 2007 Elsevier B.V. All rights reserved
The Genome-Based Metabolic Systems Engineering to Boost Levan Production in a Halophilic Bacterial Model
No full textMetabolic systems engineering is being used to redirect microbial metabolism for the overproduction of chemicals of interest with the aim of transforming microbial hosts into cellular factories. In this study, a genome-based metabolic systems engineering approach was designed and performed to improve biopolymer biosynthesis capability of a moderately halophilic bacterium Halomonas smyrnensis AAD6(T) producing levan, which is a fructose homopolymer with many potential uses in various industries and medicine. For this purpose, the genome-scale metabolic model for AAD6(T) was used to characterize the metabolic resource allocation, specifically to design metabolic engineering strategies for engineered bacteria with enhanced levan production capability. Simulations were performed in silico to determine optimal gene knockout strategies to develop new strains with enhanced levan production capability. The majority of the gene knockout strategies emphasized the vital role of the fructose uptake mechanism, and pointed out the fructose-specific phosphotransferase system (PTSfru) as the most promising target for further metabolic engineering studies. Therefore, the PTSfru of AAD6(T) was restructured with insertional mutagenesis and triparental mating techniques to construct a novel, engineered H. smyrnensis strain, BMA14. Fermentation experiments were carried out to demonstrate the high efficiency of the mutant strain BMA14 in terms of final levan concentration, sucrose consumption rate, and sucrose conversion efficiency, when compared to the AAD6(T). The genome-based metabolic systems engineering approach presented in this study might be considered an efficient framework to redirect microbial metabolism for the overproduction of chemicals of interest, and the novel strain BMA14 might be considered a potential microbial cell factory for further studies aimed to design levan production processes with lower production costs
Simultaneous inhibition of PFKFB3 and GLS1 selectively kills KRAS-transformed pancreatic cells
No full textActivating mutations of the oncogenic KRAS in pancreatic ductal adenocarcinoma (PDAC) are associated with an aberrant metabolic phenotype that may be therapeutically exploited. Increased glutamine utilization via glutaminase-1 (GLS1) is one such feature of the activated KRAS signaling that is essential to cell survival and proliferation; however, metabolic plasticity of PDAC cells allow them to adapt to GLS1 inhibition via various mechanisms including activation of glycolysis, suggesting a requirement for combinatorial anti-metabolic approaches to combat PDAC. We investigated whether targeting the glycolytic regulator 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase-3 (PFKFB3) in combination with GLS1 can selectively prevent the growth of KRAS-transformed cells. We show that KRAS-transformation of pancreatic duct cells robustly sensitizes them to the dual targeting of GLS1 and PFKFB3. We also report that this sensitivity is preserved in the PDAC cell line PANC-1 which harbors an activating KRAS mutation. We then demonstrate that GLS1 inhibition reduced fructose-2,6-bisphosphate levels, the product of PFKFB3, whereas PFKFB3 inhibition increased glutamine consumption, and these effects were augmented by the co-inhibition of GLS1 and PFKFB3, suggesting a reciprocal regulation between PFKFB3 and GLS1. In conclusion, this study identifies a novel mutant KRAS-induced metabolic vulnerability that may be targeted via combinatorial inhibition of GLS1 and PFKFB3 to suppress PDAC cell growth.Fil: Ozcan, Selahattin C.. Koc University Research Center For Translational Medici; TurquíaFil: Mutlu, Aydan. Bursa Uludag University; TurquíaFil: Altunok, Tugba H.. Bursa Uludag University; TurquíaFil: Gurpinar, Yunus. Bursa Uludag University; TurquíaFil: Sarioglu, Aybike. Bursa Uludag University; TurquíaFil: Guler, Sabire. Bursa Uludag University; TurquíaFil: Muchut, Robertino José. Universidad Nacional del Litoral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Iglesias, Alberto Alvaro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral; ArgentinaFil: Celikler, Serap. Bursa Uludag University; TurquíaFil: Campbell, Paul M.. The Marvin and Concetta Greenberg Pancreatic Cancer Institute; Estados UnidosFil: Yalcin, Abdullah. Bursa Uludag University; Turquí
Generalized Z-contraction on quasi metric spaces and a fixed point result
No full textThe simulation function is defined by Khojasteh et al. [F. Khojasteh, S. Shukla, S. Radenovic, Filomat, 29 (2015), 1189-1194]. Khojasteh introduced the notion of Z-contraction which is a new type of nonlinear contractions defined by using a specific simulation function. Then, they proved existence and uniqueness of fixed points for Z-contraction mappings. After this work, studies involving simulation functions were performed by various authors [H. H. Alsulami, E. Karapinar, F. Khojasteh, A. F. Roldan-Lopez-de-Hierro, Discrete Dyn. Nat. Soc., 2014 (2014), 10 pages], [M. Olgun, O. Bicer, T. Alyildiz, Turkish J. Math., 40 (2016), 832-837]. In this paper, we introduce generalized simulation function on a quasi metric space and we present a fixed point theorem. (C) 2017 All rights reserved
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