Beslenme ve Diyetetik Bölümü Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12514/223

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Adsorption and inhibition effect of 2,4-diamino-6-hydroxypyrimidine for mild steel corrosion in HCl medium: experimental and theoretical investigation
(SPRINGER HEIDELBERG, 2019) Yildiz, Resit; Yıldız, Reşit
2,4-Diamino-6-hydroxypyrimidine (2D6H) was examined as corrosion inhibitor of mild steel (MS) in 0.1M HCl using potentiodynamic measurements, linear polarization resistance (LPR), scanning electron microscopy, electrochemical experiments, and quantum chemical calculations. All measurements show that the corrosion inhibition effectiveness is forthright compared to the concentration of 2D6H ranging from 0.5 to 10.0mM. Adsorption of 2D6H on the MS surface in the presence of HCl is determined to obey Langmuir adsorption isotherm. The electronic features elucidated by quantum chemical calculations were associated with the experimental inhibition productivities. The mechanism of inhibition was revealed by E-pzc measurements.
Diagnostic Performance of Erythropoietin and Erythropoietin Receptors Levels in Children with Attention Deficit Hyperactivity Disorder
(Clinical Psychopharmacology and Neuroscience, 2021) Güngör, Meltem; Ergul Belge Kurutas, Erkan Oner, Velid Unsal, Hatice Altun, Ali Erdinc Yalin, Serap Yalin, Ozlem Bozkus, Nilfer Sahin
Objective: Attention deficit hyperactivity disorder (ADHD) is a heterogeneous, highly heritable, a common childhood neurobehavioural disorder resulting from complex gene-gene and gene-environment interactions. The erythropoietin (Epo)/erythropoietin receptors (EpoR) system turned out to have additional important functions in nonhematopoietic tissue. In this study, we aimed to investigate the levels of Epo and and EpoR, and also their diagnostic values in children with ADHD. Methods: A total of 70 children were included in the study, 35 drug-naive patients with ADHD (age: 6−12 years; male/female: 20/15) and 35 healthy controls (age: 6−12 years; male/female: 22/13). Serum Epo and EpoR levels was determined using a commercial sandwich enzyme-linked immunosorbent assay kit. Results: The results indicated that the levels of Epo decreased in patients with ADHD compared to control (p < 0.05). On the other hand, EpoR levels increased in these patients (p < 0.05). Furthermore, the ratio of Epo/EpoR was significantly lower in ADHD patients than controls (p < 0.05). Receiver operator characteristic curve analysis showed high diagnostic performance for Epo and EpoR, areas under curve were 0.980 and 1.000, respectively. Conclusion: This is the first report to investigate the association between serum Epo and EpoR levels in ADHD patients. Our results indicated that Epo may play a role in the etiology of ADHD, and Epo therapy may be beneficial in these disorders if given in addition to the routine treatment of children with ADHD. Furthermore, our results reveal possible diagnostic value of Epo and EpoR.
Electrocatalysis property of CuZn electrode with Pt and Ru decoration
(International Journal of Hydrogen Energy, 2021) Toprak Döşlü, Serap; Döner, Ali; Yıldız, Reşit; Yıldız, Reşit
Electrocatalysis properties strongly depend on the interaction of metallic particles and this interaction enables to change the electronic structure of alloys which enhances the catalytic activity. This property is the key factor in the developing of cost-effective and efficient Hydrogen Evolution Reaction (HER) electrocatalysts for sustainable hydrogen production. In this study, novel electrocatalysts which are decorated with Pt and Ru have been developed for HER electrocatalysis. Microscopic analysis such as scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD) and atomic force microscopy (AFM) are performed to determine the morphological and compositional structures. Electrocatalysis properties are evaluated by cathodic current-potential curves, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) in 1.0 M KOH solution. Chronoamperometry (CA) and cycle tests are used for stability/durability of electrocatalysts. Results show that a small onset potential of the porous Cu/Ni/CuZn–Pt is obtained for HER. Exchange current density and polarization resistance are found to be 5.39 mA cm−2 and 2.0 Ω cm2 at overpotential of −100 mV for porous Cu/Ni/CuZn–Pt, respectively, indicating that Cu/Ni/CuZn–Pt is higher electrocatalytic properties than the others. Moreover, very low overpotentials at 10 and 40 mA cm−2 are obtained on porous Cu/Ni/CuZn–Pt compared with porous Cu/Ni/CuZn–Ru and Cu/Ni/CuZn. Porous Cu/Ni/CuZn–Pt also displays excellent stability/durability in test solution. The remarkable electrocatalysis properties of porous Cu/Ni/CuZn–Pt can be explained due to high porous structure, leaching of Zn from the deposit, intrinsic activity of Pt as well as changing in the electronic structure. It should be considered that porous Cu/Ni/CuZn–Pt is of high corrosion resistance in test solution for 120 h, which makes it good candidate for HER.
Electrocatalysis property of CuZn electrode with Pt and Ru decoration
(2021) Toprak Döşlü, Serap; DÖNER, ALİ; Yıldız, Reşit; Yıldız, Reşit
Electrocatalysis properties strongly depend on the interaction of metallic particles and this interaction enables to change the electronic structure of alloys which enhances the catalytic activity. This property is the key factor in the developing of cost-effective and efficient Hydrogen Evolution Reaction (HER) electrocatalysts for sustainable hydrogen production. In this study, novel electrocatalysts which are decorated with Pt and Ru have been developed for HER electrocatalysis. Microscopic analysis such as scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD) and atomic force microscopy (AFM) are performed to determine the morphological and compositional structures. Electrocatalysis properties are evaluated by cathodic current-potential curves, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) in 1.0 M KOH solution. Chronoamperometry (CA) and cycle tests are used for stability/durability of electrocatalysts. Results show that a small onset potential of the porous Cu/Ni/CuZnePt is obtained for HER. Exchange current density and polarization resistance are found to be 5.39 mA cm2 and 2.0 U cm2 at overpotential of 100 mV for porous Cu/Ni/CuZnePt, respectively, indicating that Cu/Ni/CuZnePt is higher electrocatalytic properties than the others. Moreover, very low overpotentials at 10 and 40 mA cm2 are obtained on porous Cu/ Ni/CuZnePt compared with porous Cu/Ni/CuZneRu and Cu/Ni/CuZn. Porous Cu/Ni/CuZn ePt also displays excellent stability/durability in test solution. The remarkable electrocatalysis properties of porous Cu/Ni/CuZnePt can be explained due to high porous structure, leaching of Zn from the deposit, intrinsic activity of Pt as well as changing in the electronic structure. It should be considered that porous Cu/Ni/CuZnePt is of high corrosion resistance in test solution for 120 h, which makes it good candidate for HER.
The electrochemical synthesis and corrosion behaviour of TiO2/poly(indole-co-aniline) multilayer coating: Experimental and theoretical approach
(Arabian Journal of Chemistry, 2018) Toprak Döşlü, Serap; Doğru Mert, Başak; Yazıcı, Birgül
The aim of this study was to protect stainless steel against corrosion via poly (indole-co-aniline) with the help of titanium dioxide pre-coating. Different monomer ratios (1:1 and 1:9) wereapplied in order to determine the suitable chain composition to synthesize the copolymer in lithiumperchlorate containing acetonitrile. The structures, morphologies, electrochemical properties andcorrosion resistances of the mono and multi-layer coatings were investigated by Fourier-transform infrared spectra, scanning electron microscope, energy dispersive X-ray spectrometer,electrochemical impedance spectroscopy and anodic polarization. Furthermore the geometric struc-ture and electronic properties of indole, aniline, and indole-co-aniline (dimmer) molecules have beeninvestigated by quantum calculations. The results indicated that corrosion protection of copolymerswas increased via titanium dioxide pre-coating. The 1:1 copolymer coating showed better corrosionprevention than 1:9 coating. The correlation was determined between experimental and theoreticalparameters.
Evaluation of fatty acids, free fatty acids and textural properties of butter and sadeyag (anhydrous butter fat) produced from ovine and bovine cream and yoghurt
(ScienceDirect, 2022) Karakuş, Mehmet Şükrü; Yıldız Akgül, Filiz; Korkmaz, Aziz; Atasoy, Ahmet Ferit
Fatty acids (FAs), free fatty acids (FFAs) and textural characteristics were determined in butter and sadeyag (anhydrous butter fat) manufactured from ovine and bovine cream and yoghurt. The samples made from cream and yoghurt had similar FA and FFA profiles and textural properties. Ovine milk fat products had higher short- and medium-chain saturated fatty acid (SFA) content, while samples made with bovine milk fat had higher long-chain SFA content. Ovine milk fat samples contained higher levels of capric, myristic, stearic and oleic acids and lower levels of butyric and caproic acids than bovine milk samples. Bovine milk fat products had firmer and poorer spreadability, and lower adhesiveness than ovine milk fat products. Polyunsaturated fatty acid (PUFA) content of butter was higher than that of sadeyag. Sadeyag was firmer and less spreadable than butter. Textural characteristics of the milk fat products depended on the FA composition of the samples.
Green Synthesis of Silver Nanoparticles Derived from Papaver rhoeas L. Leaf Extract: Cytotoxic and Antimicrobial Properties
(MDPI, 2023) İpek, Polat; Yıldız, Reşit; Baran, Mehmet Fırat; Hatipoğlu, Abdülkerim; Baran, Ayşe; Sufianov, Albert; Beylerli, Ozal; Yıldız, Reşit
In the last few decades, the search for metal nanoparticles as an alternative to cancer treatments and antibiotics has increased. In this article, the spectroscopic (ultraviolet-visible (UV-vis), electron-dispersing X-ray (EDX), and Fourier transform infrared (FT-IR)), microscopic (field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM), and atomic force microscope (AFM)), structural (X-ray diffractometer (XRD) and zetasizer), and analytic (thermogravimetric/differential thermal analyzer (TGA-DTA)) characterization of the silver nanoparticles (AgNPs) produced from Papaver rhoeas (PR) L. leaf extract are presented. PR-AgNPs are generally spherical and have a maximum surface plasmon resonance of 464.03 nm. The dimensions of the manufactured nanomaterial are in the range of 1.47-7.31 nm. PR-AgNPs have high thermal stability and a zeta potential of 36.1 mV. The minimum inhibitory concentration (MIC) values (mg L-1) of PR-AgNPs on Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, and Candida albicans are 1.50, 0.75, 3.00, 6.00, and 0.37, respectively. In the study, the cytotoxic and proliferative effects of PR-AgNPs using the MTT (3-(4,5-dimethylthiazol-2-yl)-diphenyltetrazolium bromide) method on various cancer cell lines (CACO-2 (human colon adenocarcinoma cell), MCF-7 (human breast cancer cell), T98-G (glioblastoma multiforme cell), and healthy HUVEC (human umbilical vein endothelial cell)) cell lines are presented. After 24 and 48 h of the application, the half-maximum inhibitory concentration (IC50) values (mu g mL(-1)) of PR-AgNPs on HUVEC, CACO-2, MCF-7, and T98-G lines are 2.365 and 2.380; 2.526 and 2.521; 3.274 and 3.318; 3.472 and 3.526, respectively. Comprehensive in vivo research of PR-AgNPs is proposed to reveal their potential for usage in sectors such as nanomedicine and nanochemistry.
Investigation of oxidant/antioxidant and anti-inflammatory effects of apigenin on apoptosis in sepsis-induced rat lung
(Journal of Biochemical and Molecular Toxicology, 2021) Unsal, Velid; Çiçek, Mustafa; Doganer, Adem; Demir, Mehmet
We suppose that apigenin may inhibit the cellular process of sepsis-induced lung injury, which is considered to be a major cause of morbidity and mortality, and may improve inflammation and oxidative stress. The aim of this study was to investigate the potential protective effect of apigenin in a rat model of polymicrobial sepsis. Eight groups consisting of a total of 64 female Wistar albino rats were used for this study. Pro-inflammatory (TNF-α, IL-1-β, IL-6) and anti-inflammatory (TGF-β, IL-10) cytokine levels were measured with the enzyme-linked immunosorbent assay technique, oxidant/antioxidants parameters were measured using the spectrophotometric method and Bax and Caspase-3 immunohistochemical methods. TNF-α, TGF-β, IL-1β, and IL-6 levels significantly increased in the sepsis-induced group than in the control groups, while IL-10 levels decreased. Lipid peroxidase (LPO), an oxidative stress marker, increased, while the antioxidant defense parameters of superoxide dismutase (SOD), catalase (CAT) activities, glutathione (GSH) levels decreased. Although Bax and Caspase-3 immunoreactivity and H score levels significantly increased in the sepsis group, significant decreases were found in the groups treated with apigenin. In conclusion, we are of the opinion that apigenin treatment improves lung injury by inhibiting oxidative stress and inflammatory cell damage.
Seasonal Variations in the Fatty Acid Composition of Phospholipid and Triacylglycerol in Gonad and Liver of Mastacembelus simack
(SPRINGER, 2015) Kaçar, Semra; Başhan, Mehmet
The seasonal effects on the fatty acid composition of triacylglycerol (TG) and phospholipid (PL) in the gonad and liver of Mastacembelus simack were determined using the gas chromatographic method. The most abundant fatty acids in the investigated seasons and tissues were palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1n-9), palmitoleic acid (C16:1n-7), arachidonic acid (C20:4n-6), eicosapentaenoic acid (C20:5n-3), and docosahexaenoic acid (C22:6n-3). The distribution proportions of aSFA (saturated fatty acids), aMUFA (monounsaturated fatty acids) and aPUFA (polyunsaturated fatty acids) were found to be different among PL and TG fractions in all seasons. The total lipid content of gonad and liver were 1.32 (November)-4.90 % (September) and 1.32 (September)-3.94 % (January), respectively. It was shown that the total lipid and fatty acid compositions in the gonad and liver of fish were significantly influenced by seasons.
Seasonal variations in the fatty acid composition of phospholipids and triacylglycerols of brown trout
(WILEY-BLACKWELL, 2015) Kayhan, H.; Başhan, Mehmet; Kaçar, Semra
Seasonal variations on phospholipid (PL) and triacylglycerol (TG) fatty acid (FA) compositions in muscles of Salmo trutta macrostigma were investigated by gas chromatography (GC) using the method described by Folch. The total lipid of the muscle was extracted using chloroform/methanol (2: 1, v/v) and was separated into TG and PL using thin layer chromatography (TLC). A total of nineteen and sixteen different fatty acids were determined in TG and PL, respectively. The distributions of Sigma SFAs (saturated fatty acids), Sigma MUFAs (monounsaturated fatty acids) and Sigma PUFAs (polyunsaturated fatty acids) proportions were found to be different among PL and TG fractions in all seasons. TG contained a lower proportion of Sigma PUFA, but a higher proportion of Sigma MUFA and Sigma SFA than PL. The major components were palmitic acid (16: 0), oleic acid (18: 1 n-9), eicosapentaenoic acid (EPA, 20: 5 n-3) and docosahexaenoic acid (DHA, 22: 6 n-3) in PL, 16: 0, palmitoleic acid (16: 1 n-7), 18: 1 n-9, linoleic acid (LA, 18: 2 n-6), linolenic acid (ALA, 18: 3 n-3), 20: 5 n-3 and 22: 6 n-3 in TG extracted from muscle of S. trutta macrostigma in all seasons. The total lipid content varied seasonally from 1.44% to 1.90% in female muscle of wet weight for S. trutta macrostigma. N-3/n-6 ratios of PL and TG were found to be 5.19-12.0 and 1.09-2.62, respectively.
A study of chewing muscles: Age-related changes in type I collagen and matrix metalloproteinase-2 expression
(ScienceDirect, 2020) Çiçek, Mustafa; Tumer, Mehmet Kemal; Unsal, Velid
Objective: In this study, the aim was to investigate the biochemical, physiological and histological changes that occur in masticatory muscles of the masticatory system with aging. Design: In this study, 14 BALB/c mice were used. Animals were divided into two equal groups of seven. Group I was organized as the group of young animals (n = 7) and Group II as the group of adult animals (n = 7). After routine histological follow-up was performed, the tissues were embedded in paraffin. 4-5 μm thick cross-sections were taken from paraffin-embedded tissues and they were stained with Haemotoxylin and Eosin Type I collagen and Matrix metalloproteinase-2 (MMP-2) immunohistochemically. Results: It was observed that there was a decrease and shrinking in blood vessels due to aging. In young mice, Type I collagen and MMP-2 immunoreactivity in the masseter muscle tissue showed low staining, while Type I collagen and MMP-2 immunoreactivity in the temporal muscle tissue showed moderate staining. Type I collagen and MMP-2 immunoreactivity were significantly higher in the masseter and temporal muscles of elderly mice (p = 0.001). In the H-score evaluation, MMP-2 immune reactivity was significantly lower in young mice than in older mice (p = 0.001). Conclusion: It was determined that severe pain complications and functional losses are likely to occur with the increase of degeneration due to aging of masticator muscles.
Toxicity of carbon tetrachloride, free radicals and role of antioxidants
(De Gruyter, 2020) Unsal, Velid; Çiçek, Mustafa; Sabancılar, İlhan
Several chemicals, including environmental toxicants and clinically useful drugs, cause severe cellular damage to different organs of our body through metabolic activation to highly reactive substances such as free radicals. Carbon tetrachloride is an organic compound of which chemical formula is CCl₄. CCl4 is strong toxic in the kidney, testicle, brain, heart, lung, other tissues, and particularly in the liver. CCl4 is a powerful hepatoxic, nephrotoxic and prooxidant agent which is widely used to induce hepatotoxicity in experimental animals and to create hepatocellular carcinoma, hepatic fibrosis/cirrhosis and liver injury, chemical hepatitis model, renal failure model, and nephrotoxicity model in recent years. The damage-causing mechanism of CCl4 in tissues can be explained as oxidative damage caused by lipid peroxidation which starts after the conversion of CCl4 to free radicals of highly toxic trichloromethyl radicals (•CCl₃) and trichloromethyl peroxyl radical (•CCl₃O2) via cytochrome P450 enzyme. Complete disruption of lipids (i.e., peroxidation) is the hallmark of oxidative damage. Free radicals are structures that contain one or more unpaired electrons in atomic or molecular orbitals. These toxic free radicals induce a chain reaction and lipid peroxidation in membrane-like structures rich in phospholipids, such as mitochondria and endoplasmic reticulum. CCl4-induced lipid peroxidation is the cause of oxidative stress, mitochondrial stress, endoplasmic reticulum stress. Free radicals trigger many biological processes, such as apoptosis, necrosis, ferroptosis and autophagy. Recent researches state that the way to reduce or eliminate these CCl4-induced negative effects is the antioxidants originated from natural sources. For normal physiological function, there must be a balance between free radicals and antioxidants. If this balance is in favor of free radicals, various pathological conditions occur. Free radicals play a role in various pathological conditions including Pulmonary disease, ischemia / reperfusion rheumatological diseases, autoimmune disorders, cardiovascular diseases, cancer, kidney diseases, hypertension, eye diseases, neurological disorders, diabetes and aging. Free radicals are antagonized by antioxidants and quenched. Antioxidants do not only remove free radicals, but they also have anti-inflammatory, anti-allergic, antithrombotic, antiviral, and anti-carcinogenic activities. Antioxidants contain high phenol compounds and antioxidants have relatively low side effects compared to synthetic drugs. The antioxidants investigated in CCI4 toxicity are usually antioxidants from plants and are promising because of their rich resources and low side effects. Data were investigated using PubMed, EBSCO, Embase, Web of Science, DOAJ, Scopus and Google Scholar, Carbon tetrachloride, carbon tetrachloride-induced toxicity, oxidative stress, and free radical keywords. This study aims to enlighten the damage-causing mechanism created by free radicals which are produced by CCl4 on tissues/cells and to discuss the role of antioxidants in the prevention of tissue/cell damage. In the future, Antioxidants can be used as a therapeutic strategy to strengthen effective treatment against substances with high toxicity such as CCl4 and increase the antioxidant capacity of cells.

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