Differential Pulse Voltammetric Determination of Fulvestrant in Pharmaceutical Dosage Forms and Serum Samples

The electrooxidation behavior and determination of fulvestrant at a glassy carbon electrode were investigated. The voltammetric study of the model compounds allowed elucidating the possible oxidation mechanism of fulvestrant. The dependence of the peak current and peak potentials on pH, concentration, nature of the buffer, and scan rate was determined. The oxidation of fulvestrant showed a single and irreversible peak at glassy carbon electrode, and the process was found diffusion controlled. Linear responses were obtained for the concentrations between 4×10−6 M and 6×10−5 M in standard samples and between 2×10−5 M and 1×10−4 M in serum samples. The repeatability of the method was found 0.93 RSD%. The repeatability, reproducibility, precision, and accuracy of proposed method were investigated

Electrochemical glucose biosensing via new generation DTP type conducting polymers/gold nanoparticles/glucose oxidase modified electrodes

WOS:000375498000013The synthesis of derivatives of dithionepyrrole is a hot subject that has been studied extensively. In this study, a novel approach for constructing different glucose biosensors using conducting polymers of 4-(4H-dithyinol[3,2-b:2',3'-d]pyro11-4-yl)aniline and 4-(4H-dithyinol[3,2-b:2',3'-d]pyroll-4-yl)-[1,1'-biphenyl]-4-amine is proposed. After the synthesis and characterizations of the dithionepyrrole type monomers, they were used in glucose biosensing applications. The surface of gold electrode was modified with mercaptoethane sulfonic acid and paminothiophenol functionalized gold nanoparticles and aniline modified GOx. Electrochemical measurements were carried out by following the consumed oxygen due to the enzymatic reaction of glucose oxidase. DTP-PhNH2/AuNP/GOx and DTP-Ph-Ph-NH2/AuNP/GOx biosensors showed very good linearity between 0.1 and 2.5 mM, and 0.05 and 1 mM for glucose, respectively. LOD value was obtained for pDTP-Ph-NH2/AuNP/GOx as 5.00 x 10(-2) mM and for pDTP-Ph-Ph-NH2/AuNP/GOx as 9.86 x 10(-5) mM using S/N ratio. Optimization of molar ratio amount of AuNP/GOx, cycles amount to immobilize AuNP/GOx, conducting polymer thickness were examined. Finally, under optimized conditions, the amount of glucose in spiked human serum samples and recovery experiments were conducted. (C) 2016 Elsevier B.V. All rights reserved.European UnionEuropean Union (EU) [CM1104]; Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [112T622, 111T135]The authors would like to thank the European Union through the COST Action CM1104 "Reducible Oxide Chemistry, Structure and Functions" and the Scientific and Technological Research Council of Turkey (TUBITAK Grant Numbers 112T622 and 111T135) for the financial support of this research

Cost-Effectiveness of Breast Cancer Screening in Turkey, a Developing Country: Results from Bahcesehir Mammography Screening Project

Objective: We used the results from the first three screening rounds of Bahcesehir Mammography Screening Project (BMSP), a 10-year (20092019) and the first organized population-based screening program implemented in a county of Istanbul, Turkey, to assess the potential cost-effectiveness of a population-based mammography screening program in Turkey

A new predictive marker for predicting response after neoadjuvant chemotherapy in hormone receptor positive/HER2-negative patients: a logarithmic model

Purpose: Estrogen receptor (ER) and progesterone receptor (PgR) levels as well as Ki-67 expression levels are independent predictive markers in patients with hormone receptor-positive breast cancer. In this study, we investigated the predictive significance of the formula of log (ER)*log (PgR)/Ki-67, which was created using 3 independent predictive markers, for the pathological complete response of the Hormone Receptor (HR)-positive/HER2-negative breast cancer patients receiving neoadjuvant chemotherapy (NACT). Methods: This retrospective study included 126 patients with HR-positive/HER2-negative breast cancer and axillary lymph node metastasis who received NACT. The log (ER)*log (PgR)/Ki-67 value was calculated from the pre-NACT pathological evaluation results in all patients. We determined the ideal predictive cut-off value, which separates patients into 2 groups according to pathological complete response (pCR) and pathological non-complete response (non-pCR), using Receiver Operating Characteristic (ROC) curve analysis. According to this cut-off point, patients were divided into 2 groups as cut-off ratio high and cut-off ratio low and were compared using logistic regression analysis along with clinicopathological features. Results: According to the predictive model, we estimated the ideal cut-off value that distinguishes patients as pCR and non-pCR to be 0.12 (p=0.015). According to this cut off value, %54.8 of the patients were categorized as cut-off value high and %46.2 were cut-off value low. The non-pCR rates of the groups were 91.3% and %71.9, respectively(p=0.004). A cutoff value of 0.12 provided the feature of being a predictive marker in the univariate analysis for distinguishing between pCR and non-pCR (OR=4.09 95% CI 1.48-11.33, p=0.007), and it preserved this feature in the multivariate analysis. (OR=3.27, 95% CI 1.12-9.56, p=0.030). Conclusion: The formula of log (ER)*log (PgR)/Ki-67 can be used as a simple and easy-to-use predictive marker for response to neoadjuvant therapy in patients with HR-positive/HER2-negative breast cancer receiving NACT. © 2021 Zerbinis Publications. All rights reserved

Uniformly Resolvable Cycle Decompositions with Four Different Factors

In this paper, we consider uniformly resolvable decompositions of complete graph K-v( or K-v minus a 1-factor I for even v) into cycles. We will focus on the existence of factorizations of K-v or K-v - I containing up to four non-isomorphic factors. We obtain all possible solutions for uniform factors involving 4, m, 2m and 4m-cycles with a few possible exceptions when m is odd

Respiratory functions in the follow-up of children with COVID-19 infection

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