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101.
Journal of Radioanalytical and Nuclear Chemistry - Various concepts involved in the quantification of radiation dose while following the theranostic approach in nuclear medicine are outlined. The... 相似文献
102.
Ashok Zakkula Sreekanth Dittakavi Malika Muskan Maniyar Naveem Syed Suresh P. Sulochana Mohd Zainuddin Ramesh Mullangi 《Biomedical chromatography : BMC》2019,33(11)
Isocitrate dehydrogenase (IDH) inhibitors comprise a novel class of anticancer drugs, which are approved to treat acute myeloid leukemia patients having mutations on IDH1/2. We report the development and validation of a high‐performance liquid chromatography (HPLC) method for the simultaneous quantitation of IDH inhibitors, namely enasidenib (EDB), ivosidenib (IDB) and vorasidenib (VDB), in mouse plasma as per the US Food and Drug Administration regulatory guidelines. The method involves extraction of EDB, IDB and VDB along with internal standard (IS; phenacetin) from mouse plasma (100 μl) using a simple protein precipitation process. The chromatographic analysis was performed on an HPLC system using a gradient mobile phase (comprising 10 mm ammonium acetate and acetonitrile in a flow‐gradient) and an X‐Terra Phenyl column. The UV detection wave length was set at λmax 265 nm. EDB, IDB, VDB and the IS eluted at 7.36, 8.60, 9.50 and 5.12 min, respectively, with a total run time of 10 min. The calibration curve was linear over a concentration range of 0.20–12.5 μg/ml for EDB and 0.50–12.5 μg/ml for IDB and VDB (r2 = ≥0.998 for all of the analytes). Validation results met the acceptance criteria. The validated HPLC method was successfully applied to a pharmacokinetic study in mice. 相似文献
103.
Zhong Ya-Qian Hossain Md. Sahadat Chen Ying Fan Qi-Hang Zhan Shu-Zhong Liu Hai-Yang 《Transition Metal Chemistry》2019,44(5):399-406
Transition Metal Chemistry - Iron complexes of corrole and porphyrin bearing electron-withdrawing meso-C6F5 groups had been used for the electrocatalytic evolution of hydrogen. In neutral buffer... 相似文献
104.
Vijayakumar Uppar Sandeep Chandrashekharappa Chandan Shivamallu Sushma P Shiva Prasad Kollur Joaquín Ortega-Castro Juan Frau Norma Flores-Holguín Atiyaparveen I. Basarikatti Mallikarjun Chougala Mrudula Mohan M Govindappa Banuprakash Jayadev Katharigatta N. Venugopala Belakatte P. Nandeshwarappa Ravindra Veerapur Abdulaziz A. Al-Kheraif Abdallah M. Elgorban Asad Syed Kiran K. Mudnakudu-Nagaraju Basavaraj Padmashali Daniel Glossman-Mitnik 《Molecules (Basel, Switzerland)》2021,26(9)
105.
Nada Abdullah Yahya Tamimi Sergey Dobretsov Najwa Al Balushi Jalila Alshekaili Hamed Al Balushi Mahmood Al Kindi Syed Imran Hassan Shadia Al Bahlani Benjamin K. Tsang Ikram A. Burney 《Molecules (Basel, Switzerland)》2021,26(12)
High-grade epithelial ovarian cancer is a fatal disease in women frequently associated with drug resistance and poor outcomes. We previously demonstrated that a marine-derived compound MalforminA1 (MA1) was cytotoxic for the breast cancer cell line MCF-7. In this study, we aimed to examine the effect of MA1 on human ovarian cancer cells. The potential cytotoxicity of MA1was tested on cisplatin-sensitive (A2780S) and cisplatin-resistant (A2780CP) ovarian cancer cell lines using AlamarBlue assay, Hoechst dye, flow cytometry, Western blot, and RT-qPCR. MA1 had higher cytotoxic activity on A2780S (IC50 = 0.23 µM) and A2780CP (IC50 = 0.34 µM) cell lines when compared to cisplatin (IC50 = 31.4 µM and 76.9 µM, respectively). Flow cytometry analysis confirmed the cytotoxic effect of MA1. The synergistic effect of the two drugs was obvious, since only 13% of A2780S and 7% of A2780CP cells remained alive after 24 h of treatment with both MA1 and cisplatin. Moreover, we examined the expression of bcl2, p53, caspase3/9 genes at RNA and protein levels using RT-qPCR and Western blot, respectively, to figure out the cell death mechanism induced by MA1. A significant down-regulation in bcl2 and p53 genes was observed in treated cells compared to non-treated cells (p < 0.05), suggesting that MA1 may not follow the canonical pathway to induce apoptosis in ovarian cancer cell lines. MalforminA1 showed promising anticancer activity by inducing cytotoxicity in cisplatin-sensitive and cisplatin-resistant cancer cell lines. Interestingly, a synergistic effect was observed when MA1 was combined with cisplatin, leading to it overcoming its resistance to cisplatin. 相似文献
106.
Hossain‐Ali Rafiee‐Pour Abdollah Noorbakhsh Abdollah Salimi Hedayatollah Ghourchian 《Electroanalysis》2010,22(14):1599-1606
Direct electron transfer of immobilized superoxide dismutase (Cu, Zn‐SOD) onto silicon carbide (SiC) nanoparticles displays a pair of well defined and nearly reversible redox peaks with formal potential (E°′) of −0.03 V in pH 7.4. The heterogeneous electron transfer rate constant (ks) and surface coverage (Γ) of immobilized SOD are 11.0±0.4 s−1 and 1.42×10−11 mol cm−2. Biosensor shows fast amperometric response (3s) with sensitivity and detection limit of 1.416 nA μM−1, 1.66 μM, and 1.375 nA μM−1, 2.1 μM for cathodically or anodically detection of superoxide, respectively. This biosensor also exhibits good stability, reproducibility and long life‐time. 相似文献
107.
Glutaric Acid Assisted Fabrication of CuO Nanostructures and their Application in Development of Highly Sensitive Electrochemical Sensor System for Carbamates 下载免费PDF全文
Razium Ali Soomro Keith Richard Hallam Zafar Hussain Ibupoto Aneela Tahira Syed Tufail Hussain Sherazi Siraj Juddin Sana Jawaid Magnus Willander 《Electroanalysis》2016,28(7):1634-1640
This work describes the fabrication of unique arrow head shaped CuO nanostructures using simple hydrothermal treatment method. The highly attractive features were obtained by the application of glutaric acid utilised simultaneous as template and functionalising agent. The functionalised nanostructures were known to possess excellent potential towards the electro‐catalytic oxidation of carbofuran pesticide. The generated intense electrochemical signal with lower potential value enabled sensitive and selective determination of carbofuran up to 1×10?3 µM with wide sensing window in range of 0.01 to 0.16 µM. The feasibility of the developed sensor system for the practical application was also studied by testing its potential in real sample extracts of various vegetables. The excellent recoveries demonstrated the analytical robustness of the developed sensor system. The sensor system utilises a new and simple approach towards sensitive determination of toxic pesticides reflecting its wide spectrum application in various fields. 相似文献
108.
A new C‐glycosyl flavone containing a 3‐keto sugar, isocassiaoccidentalin B ( 1 ), was isolated from whole Cassia nomame (Sieber ) Honda plants, along with eleven known compounds, including two flavonoids ( 2 and 3 ), five flavonoid glycosides ( 4 – 8 ), two chalcones ( 9 and 10 ), and two phenylpropanoids ( 11 and 12 ). The chemical structures of all compounds were determined via 1D‐ and 2D‐NMR, and ESI‐MS. Among these, compounds 2 , 3 , 7 , and 8 were found to be the most potent in inhibiting nitric oxide release. Compounds 1 , 2 , 4 , 8 , 9 , and 10 showed significant free‐radical scavenging activity. 相似文献
109.
Synthesis,characterization, dielectric and rectification properties of PANI/Nd2O3:Al2O3 nanocomposites 下载免费PDF全文
Juhi Nishat Ansari Syed Khasim Ameena Parveen Omar A Al‐Hartomy Ziad Khattari Nacer Badi Aashis. S. Roy 《先进技术聚合物》2016,27(8):1064-1071
Polyaniline–Nd2O3:Al2O3 nanocomposites were prepared by in situ oxidative polymerization method using different weight percentages of oxide powders. The prepared nanocomposites were characterized by Fourier transform infrared spectroscopy and X‐ray diffraction for molecular and crystal structures. Scanning electron microscopy and transmission electron microscopy images show the tubular structure of polyaniline nanocomposite with embedded metal oxides. The electrical conductivity of the nanocomposites increases with increase in temperature as well as with concentration of Nd2O3:Al2O3 particles in polyaniline. This is because of the hopping of charge polarons and extended chain length of the nanocomposites as evidenced by the negative thermal coefficient (NTC) characteristic. A high NTC value of 2.67 was found in nanocomposites with 15 wt% of oxide particles. These nanocomposites show low dielectric constant and dielectric loss; the electrical conductivity is higher than 0.3 S/cm as confirmed by Cole–Cole plot that indicates a decrease in both grain resistance and bulk resistance of the nanocomposites. The current–voltage and capacitance–voltage measurements were also carried out. The carrier mobility μ values of pure polyaniline and nanocomposites were found to be 4.27 × 10?3 and 1.45 × 10–2 H.M?1, respectively. A significant enhancement in carrier mobility was observed in comparison with the literature. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
110.
The title ion–molecule reaction has been proposed to play an important role in interstellar chemistry if it yields acrylonitrile ions CH2CH–CN+. This question was probed by examining the formation of HCCH+ and HCN from low-energy ions CH2CH–CN+ and related isomers, using tandem mass spectrometry based experiments (D and 13C labelling) in conjunction with model chemistry calculations (CBS-QB3/APNO). We conclude that the title reaction is a barrierless multistep rearrangement that may not effectively compete with the straightforward formation of stable distonic ions HCCH–NCH+ from HCCH+(ion)–HCN(dipole) encounter complexes. 相似文献