Bisfenol A’ya maruz kalan erkek Yeni Zelanda tavşanlarında punikalajinin potansiyel etkileri

The possible effects of punicalagin on some oxidant-antioxidant enzymes and biochemical parameters in bisphenol A (BPA)-treated rabbits were investigated. Animals were randomly divided into 4 groups, each containing 6 rabbits: Control (C; corn oil and distilled water), BPA (BPA; 20 mg/kg BPA in corn oil and distilled water), the punicalagin (PUN; corn oil and 2 mg/kg punicalagin in distilled water), and BPA-punicalagin (B+P; 20 mg/kg BPA in corn oil and 2 mg/kg PUN in distilled water) groups. Daily treatments continued for 9 weeks and doses were adjusted according to body weights measured for each week. At the end of the study, hematological, biochemical, and oxidant-antioxidant parameters were measured from blood and tissue samples. The difference in the levels of plasma bilirubin, albumin, total plasma protein, Mg, P, Ca, Na, K, and levels of glutathione peroxidase in plasma, liver, and kidney were non-significant (p>0.1). However, oral BPA administration adversely affected serum cholesterol, LDL, HDL, amylase, lipase, CRP, and GGT concentrations. Likewise, malondialdehyde, catalase, and superoxide dismutase levels in the kidney and liver were also negatively altered by BPA (p<0.05). Significant improvements in these parameters were apparent in the B+P group. The data generated here showed that punicalagin possessed a beneficial impact on potentially reducing the possible toxic effects of BPA in rabbits.Çalışmada, BPA verilen Yeni Zelanda tavşanlarında punikalajininbazı oksidan-antioksidan enzimler ile bazı biyokimyasal parametreler üzerine olası etkilerin incelendi. Bu amaçla 2 hafta boyunca laboratuvar koşullarına alıştırılan tavşanlar, her grupta 6 tavşan olacak şekilde rastgele 4 gruba ayrıldı: Kontrol (C; mısır yağı ve distile su), BPA (BPA; mısır yağı içerisinde 20 mg/kg BPA ve distile su), punikalajin (PUN; mısır yağı ve distile su içerisinde 2 mg/kg punikalajin), ve BPA-punikalajin grubu (B+P; mısır yağı içerisinde 20 mg/kg BPA ve distile su içerisinde 2 mg/kg PUN). Uygulamalar 9 hafta boyunca günlük olarak yapıldı ve haftada bir kez yapılan tartımlara göre dozlar ayarlandı. Çalışma sonunda alınan kan ve doku örneklerinden hematolojik, biyokimyasal ve oksidanantioksidan parametrelerin ölçümleriyapıldı. Analizler neticesinde plazma bilirubin, albümin ve toplam plazma protein düzeyleri ile Mg, P, Ca, Na, K, seviyelerinde herhangi bir istatistiki farka rastlanmazken, farklı gruplardaki plazma, karaciğer ve böbrek glutatyon peroksidaz değerleri de önemsiz bulundu (p>0,1). Oral BPA uygulamaları serum kolesterol, LDL, HDL, amilaz, lipaz, CRP, GGT seviyeleri ile karaciğer ve böbrek dokusundaki malonildialdehit, katalaz ve süperoksit dismütaz seviyelerini olumsuz etkiledi (p<0,05). B+P grubunda ise bu parametrelerde önemli ölçüde iyileşme gözlendi. Elde edilen sonuçlar, BPA'nın erkek tavşanlarda yol açtığı olası toksik etkilerin punikalajin tedavisi ile önemli ölçüde düzeltilebileceğini gösterdi

Molecular binding characterization of genetically engineered solid binding peptides

Anorganik y&uuml;zeyler &ccedil;eşitli kimyasal gruplar kullanılarak fonksiyonel hale getirilmektedirler. Bu molek&uuml;llerin y&uuml;zeylerde oluşturdukları kendiliğinden &ouml;rg&uuml;tlenen yapılar ile y&uuml;zeylere istenilen fonksiyonellik kazandırılmaktadır. Ancak, kullanılan kimyasal molek&uuml;ler bağlayıcılar tek bir y&uuml;zeye &ouml;zg&uuml;l olmamakta,birden fazla y&uuml;zeye afinite g&ouml;stermektedirler. &Ccedil;oklu malzeme i&ccedil;eren y&uuml;zeylerde kimyasal bağlayıcılarla aşılamayan bu durum, son yıllarda kombinatoryel biyoloji y&ouml;ntemleri ile yeni nesil peptid molek&uuml;ler bağlayıcılar kullanilarak aşılmaya &ccedil;alışılmaktadır. Y&ouml;nlendirilmiş evrim yolu ile faj g&ouml;sterim ve h&uuml;cre y&uuml;zey g&ouml;sterim teknikleri kullanılarak farklı malzeme y&uuml;zeylerine &ouml;zg&uuml;l olan peptitlerin molek&uuml;ler bağlayıcılar olarak kullanımı biyo-nanoteknolojik &ccedil;alismalarda artan oranda ilgi toplanmaktadir. Bu &ccedil;alışma kapsamında altın, platin ve silika y&uuml;zeylerine &ouml;zg&uuml;l olarak se&ccedil;ilmiş peptidlerin, adsorpsiyon kinetik parametreleri, peptidlerin yapısal &ouml;zellilklerine bağlı olarak incelenmistir. Bu &ccedil;alışma dahilinde peptidlerin anorganik y&uuml;zeylerle etkileşimleri y&uuml;zey plazmon spektrometresi ile incelenmiştir. Deneylerde, peptidlerin ilk se&ccedil;ilmis dizileri ile &nbsp;&ccedil;oklu tekrarlarından oluşmuş diziler kullanılmıştır. &Ccedil;alışma sonucunda platine &ouml;zg&uuml;l PtBP2, silikaya &ouml;zg&uuml;l bağlanan QBP1 ve altına &ouml;zg&uuml;l bağlanan GBP, molek&uuml;llerinde bu peptidlerin orijinal aminaasit dizilerinin &uuml;&ccedil;l&uuml; tekrarlarının y&uuml;zeylerde kaplama y&uuml;zdesini artırdığı g&ouml;r&uuml;lm&uuml;şt&uuml;r. Ancak platine &ouml;zg&uuml;l PtBP1 ve silikaya &ouml;zg&uuml;l QBP2 peptidlerinde aynı durum g&ouml;zlenememiştir. Bu &ccedil;alışma sonu&ccedil;unda anorganik y&uuml;zeylere &ouml;zg&uuml;l peptidlerin g&ouml;stermiş oldukları y&uuml;ksek y&uuml;zey kaplama oranları sayesinde, katı y&uuml;zeylerin işlevselleştirilmesi i&ccedil;in iyi birer molek&uuml;ler bağlayıcı oldukları saptanmıştır.Anahtar Kelimeler: Peptidler, y&uuml;zey işlevselliği, molek&uuml;ler tanıma, biyo-nanoteknoloji.Molecular recognition abilities of peptides and proteins have been exploited to create new generation of biomimetic molecular linkers. Peptide based molecular linkers were selected using combinatorial biology techniques, namely cell surface and phage display methods. Genetically engineered peptides for inorganics (GEPI) were screened and selected from phage display or cell surface display libraries. GEPIs were first characterized using qualitative techniques. However, this test was used as a preliminary step for the classification of the GEPIs. In this study we focused on the surface coverage of GEPIs. In the molecular characterization of GEPIs, adsorption kinetics and thermodynamics of GEPIs were realized in conjugation with secondary structural analysis of GEPIs. To characterize binding kinetics and thermodynamics of GEPIs, we employed surface plasmon resonance sensor. The sensing capability of SPR was only limited for adsorption on gold surface. We employed a reflectivity model, improved in Sarikaya group, to extend the sensing capability of SPR for the materials other than gold, namely platinum and silica surfaces. The reflectivity model guided us to prepare the right architecture for platinum and silica coated SPR chip surfaces. The surface coverage for gold binding peptide (l-GBP), platinum binding peptides (l-PtBP1and l-PtBP2) and silica binding peptides (l-QBP1 and l-QBP2) were determined. We carried out the surface coverage experiments for the one repeat of the peptides as they were selected from the libraries. GBP, gold binding peptide was selected from a cell surface display library. It is a 14 mer peptide and in previous studies it was demonstrated to have a high affinity to gold. Here we employed a surface coverage analysis for both l-GBP and its concatamer form 3l-GBP. For surface coverage analysis of GBP we found that there is a difference between l-GBP and 3l-GBP.  The increase in surface coverage was not as prominent as the increase in binding affinity. We observed that the surface coverage of peptides were greatly influenced by the concentration of the peptide. Interestingly the difference in surface coverage of GEPIs was noticed at low concentrations of the peptides. In silica binding peptides groups, we tested two distinct silica binding peptides. QBP1 and QBP2. Both of the peptides were designed using bioinformatics tools, based on the knowledge generated from a combinatorially selected phage display library members. For QBP1 we noticed that, there is a difference in the surface coverage of the concatamer form, 3l, of the peptide. Interestingly we did not see any difference in the surface coverage of the one repeat and three repeat forms of QBP2. They seem similar to each other. The increase in the surface coverage upon displaying the concatamer forms of the peptides is regardless that the peptides are strong binder or not. We observed a comparable behaviour in the Pt binding peptides with the silica binding peptides in case of the repeating concatamers on surface coverage of the peptides. Here we investigated two platinum binders PtBP1 and PtBP2. They were both selected from phage display library as 7mer cyclic peptides. In PtBP1 peptide we did not observe any difference between the surface coverage values of l-PtBP1 and 3l-PtBP1. However, we noticed a difference between the surface coverages of l-PtBP2 and 3l-PtBP2. Despite of the fact that they were the strong binding peptides, they behaved differently in their surface coverage analysis. Here we demonstrated the surface coverages of PtBPs, QBPs and GBPs as a function of concentration. All of these peptides were the strongest binders for their corresponding surfaces. However, we explored a difference for their adsorption properties. Here we showed that the surface coverage of the peptides is not increasing as the number of GEPIs is increasing. The increase in the surface coverage of a GEPI is depended to the primary structure information of GEPI. Since the primary structure determines the secondary structure, we can conclude that , if the increase in the number of the repeats of GEPI favor for the conformational stability on the surface, then the surface coverage of the given GEPI increases. Surface coverage of a GEPI can be tuned by changing the conformational constraints affecting its structural stability on the surface. These properties make inorganic binding peptides ideal self assembling molecular tools for bionanotechnological applications. Keywords: Inorganic binding peptides, surface plasmon resonance, bio-nanotechnology, surface coverage

Doxycycline plus streptomycin versus ciprofloxacin plus rifampicin in spinal brucellosis [ISRCTN31053647]

Background: The optimal treatment regimen and duration of the therapy is still controversial in spinal brucellosis. The aim of this study is to compare the efficacy, adverse drug reactions, complications and cost of ciprofloxacin plus rifampicin versus doxycycline plus streptomycin in the treatment of spinal brucellosis

Peptide-directed co-assembly of nanoprobes on multimaterial patterned solid surfaces

This is the published version. Copyright 2012 Royal Society of ChemistryBiocombinatorially selected solid-binding peptides, through their unique material affinity and selectivity, are a promising platform for building up complex hierarchical assemblies of nanoscale materials and molecular probes, targeted to specific practical solid surfaces. Here, we demonstrate the material-specific characteristics of engineered gold-binding and silica-binding peptides through co-assembly onto micro- and nano-patterned gold surfaces on silica substrates. To build hierarchical nanostructures on patterned solid surfaces, we utilize peptides as molecular tools and monitor their behavior by either conjugating biotin to them for specific affinity to streptavidin-coated QDot nanoparticles or labelling them with small fluorescent labels. This biomimetic peptide-based approach could be used as an alternative to conventional chemical coupling and surface functionalization techniques with substantial advantages, allowing simultaneous assembly of two or more inorganic nano-entities and/or molecular probes onto patterned inorganic solid substrates. The results have significant implications in a wide range of potential applications, including controlled assembly of hybrid nanostructures in bionanophotonic and biosensing devices

Wettability and surface roughness characteristics of medium density fiberboard panels from rhododendron (rhododendron ponticum) biomass

Wettability and surface roughness properties of medium density fiberboard (MDF) panels made from Rhododendron biomass were examined in this study. Rhododendron dominates the understory layer of the forests throughout the Black Sea Region in Turkey with substantial biomass potential. This study was conducted to evaluate suitability of Rhododendron fiber for MDF production. For the experiments, rhododendron and commercially-manufactured-chip (Pinus sylvestris L. and Quercus robur L.) with 11% moisture content were used. The mixing ratios of rhododendron with commercially-manufactured-chip were 100:0, 75:25, 50:50, 25:75 and 0:100 %, respectively. Commercial urea formaldehyde (UF) adhesive was used as a binder. A stylus method was employed to evaluate the surface characteristics of the samples. Roughness measurements by the stylus method were taken perpendicularly to the fiber. There was a significant diff erence (p=0.05) between surface roughness parameters (Ra, Rz, Rq, and Ry). Th e results obtained in this study revealed that all the panels have met the general purpose-use requirements of European Norm (EN). It was found that panels made with a 25/75 ratio of rhododendron to commercially-manufactured-chip had a significantly lower contact angle (88.14o) than panels made with a 100/0 ratio (117.91o). Surface roughness measurements are based on four roughness parameters, average roughness (Ra), mean peak-to-valley height (Rz), root mean square roughness (Rq), and maximum peak-to-valley height (Ry) were considered to evaluate the surface characteristics of the panels and supported the above findings as the panels made with a 25/75 ratio had a slightly rougher surface with average values of 2.929 μm (Ra). From the tests performed, we conclude that increasing the rhododendron mixing portion increased surface roughness and decreased wettability. Based on these results, rhododendron biomass could be an alternative raw material for MDF manufacturing

Engineered Escherichia coli Silver-Binding Periplasmic Protein That Promotes Silver Tolerance

This is the published version. Copyright © 2012, American Society for Microbiology. All Rights Reserved.Silver toxicity is a problem that microorganisms face in medical and environmental settings. Through exposure to silver compounds, some bacteria have adapted to growth in high concentrations of silver ions. Such adapted microbes may be dangerous as pathogens but, alternatively, could be potentially useful in nanomaterial-manufacturing applications. While naturally adapted isolates typically utilize efflux pumps to achieve metal resistance, we have engineered a silver-tolerant Escherichia coli strain by the use of a simple silver-binding peptide motif. A silver-binding peptide, AgBP2, was identified from a combinatorial display library and fused to the C terminus of the E. coli maltose-binding protein (MBP) to yield a silver-binding protein exhibiting nanomolar affinity for the metal. Growth experiments performed in the presence of silver nitrate showed that cells secreting MBP-AgBP2 into the periplasm exhibited silver tolerance in a batch culture, while those expressing a cytoplasmic version of the fusion protein or MBP alone did not. Transmission electron microscopy analysis of silver-tolerant cells revealed the presence of electron-dense silver nanoparticles. This is the first report of a specifically engineered metal-binding peptide exhibiting a strong in vivo phenotype, pointing toward a novel ability to manipulate bacterial interactions with heavy metals by the use of short and simple peptide motifs. Engineered metal-ion-tolerant microorganisms such as this E. coli strain could potentially be used in applications ranging from remediation to interrogation of biomolecule-metal interactions in vivo

Threshold voltage control in organic thin film transistors with dielectric layer modified by a genetically engineered polypeptide

This is the published version. Copyright 2010 American Institute of PhysicsPrecise control over the threshold voltage of pentacene-based organic thin film transistors was achieved by inserting a genetically engineered quartz-binding polypeptide at the semiconductor-dielectric interface. A 30 V range was accessed with the same peptide by adjusting the pH of the solution for peptide assembly while leaving other device properties unaffected. Mobility of 0.1–0.2 cm2 V−1 s−1 and on/off current ratio of >106 could be achieved for all devices regardless of the presence of the neutral peptide or the peptide assembled in acidic or basic conditions. This shift in threshold voltages is explained by the generation of charged species and dipoles due to variation in assembling conditions. Controlling device characteristics such as threshold voltage is essential for integration of transistors into electronic circuits

Determine of Alternative Ideas of Science Teacher Candidates’ about Some Astronomical Concepts

Araştırmanın amacı Teknoloji Destekli Öğretim (TEDÖ) uygulamaları kapsamında öğretim gören fen bilgisi öğretmen adaylarının öğretim uygulamalarından önce ve sonra astronominin bazı temel kavramlarına yönelik alternatif fikirlerini belirlemektir. Çalışma tek grup ön-son test yarı deneysel desen ile yürütülmüştür. Araştırma, Fen Bilgisi Eğitimi programında okuyan ve astronomi dersini alan 77 öğretmen adayı ile gerçekleştirilmiştir. Bektaşlı (2013) tarafından geliştirilen Astronomi Kavram Testi (AstroCoT) ölçeği kullanılarak elde edilen veriler, SPSS 22 programı kullanılarak betimsel analiz teknikleriyle ve Bao (1999) tarafından geliştirilen analiz tekniği esas alınarak analiz edilmiştir. Araştırma sonucunda temel astronomi kavramlarına yönelik olarak fen bilgisi öğretmen adaylarının alternatif fikirlerle öğrenme ortamına geldiği ve öğrencilerin genellikle çeldiricilerde yığıldığı görülmektedir. Katılımcıların uygulama öncesi ve sonrası alternatif fikirleri değerlendirildiğinde genelde öğrencilerin TEDÖ uygulamaları sonrasında alternatif fikirlerinin azaldığı görülmektedir. Katılımcıların son test skorları ve yoğunlaşmalarının orta ve yüksek düzeye çıkmasından da bu durum anlaşılmaktadır.The aim of this study is to determine the alternative conceptions of pre-service science teachers receiving education through Technology-Based Education (TBE) practices concerning some basic concepts of astronomy before and after the teaching practices. The single-group pretest-posttest quasi-experimental design was used in the study. The research participants were 77 pre-service teachers studying at the Department of Science Teaching of a university in Turkey and receiving the astronomy course. The data obtained through the Astronomy Concept Test (AstroCoT) developed by Bektaşlı (2013) were analyzed based on the analysis technique developed by Bao (1999) and descriptive analysis techniques via SPSS 22. It was found out that the pre-service science teachers arrived in the classroom environment with alternative conceptions concerning the basic concepts of astronomy and mostly had conceptions appearing similar to the main ones. The participants’ alternative conceptions before and after the teaching process show that their alternative conceptions had decreased by the end of the TBE practices in general. This is also evident in the participants’ posttest scores and the medium-level and high-level concentrations they displayed at the end of the process

Quantitative assessment of left atrial functions by speckle tracking echocardiography in hypertensive patients with and without retinopathy

Purpose:The association between hypertensive retinopathy and left atrial(LA) impairment is unknown. Accordingly, it was aimed to investigate the possiblerelationship between hypertensive retinopathy and LA phasic functions by means oftwo-dimensional speckle-tracking echocardiography (2D-STE).Methods:A total of 124 hypertensive patients and 27 control subjects were includedin the study. LA reservoir strain (LAS-S), LA conduit strain (LAS-E), and LA boosterstrain (LAS-A) parameters were used to evaluate LA myocardial functions.Results:Hypertensive patients (with and without retinopathy) displayed an obviousreduction in the LA reservoir strain (LAS-S),and LA conduit strain (LAS-E). Moreover,further impairment in LA reservoir and conduit strain was found in patients withhypertensive retinopathy than in the isolated hypertensive patients. There were nosignificant differences in LA booster strain (LAS-A) among the three groups. ImpairedLAS-S(OR: 0.764, CI: 0.657–0.888, andp< 0.001), LAS-E(OR: 0.754, CI: 0.634–0.897,andp=0.001), and hypertension (HT) duration (OR: 2.345, CI: 1.568–3.507, andp< 0.001) were shown to be independent predictors of hypertensive retinopathy.Conclusion:Impaired LA reservoir and conduit strain may be used to predict hyper-tensive patients at higher risk of developing hypertensive retinopathy, and to deter-mine which patients should be followed more closely for hypertensive retinopath

Why do some patients with stage 1A and 1B endometrial endometrioid carcinoma experience recurrence? A retrospective study in search of prognostic factors

Objectives: Endometrial endometrioid carcinoma (EEC) is the most encountered subtype of endometrial cancer (EC). Our study aimed to investigate the factors affecting recurrence in patients with stage 1A and 1B EEC. Material and methods: Our study included 284 patients diagnosed with the International Federation of Gynecology and Obstetrics stage 1A/1B EEC in our center from 2010 to 2018. The clinicopathological characteristics of the patients were obtained retrospectively from their electronic files. Results: The median age of the patients was 60 years (range 31–89). The median follow-up time of the patients was 63.6 months (range 3.3–185.6). Twenty-two (7.74%) patients relapsed during follow-up. Among the relapsed patients, 59.1% were at stage 1A ECC, and 40.9% were at stage 1B. In our study, the one-, three-, and five-year recurrence-free survival (RFS) rates were 98.9%, 95.4%, and 92.9%, respectively. In the multivariate analysis, grade and tumor size were found to be independent parameters of RFS in all stage 1 EEC patients. Furthermore, the Ki-67 index was found to affect RFS in stage 1A EEC patients, and tumor grade affected RFS in stage 1B EEC patients. In the time-dependent receiver operating characteristic curve analysis, the statistically significant cut-off values were determined for tumor size and Ki-67 index in stage 1 EEC patients. Conclusions: Stage 1-EEC patients in the higher risk group in terms of tumor size, Ki-67, and grade should be closely monitored for recurrence. Defining the prognostic factors for recurrence in stage 1 EEC patients may lead to changes in follow-up algorithms