Search results for "assay"
showing 10 items of 2241 documents
An overview on the recent developments of 1,2,4-triazine derivatives as anticancer compounds
2017
The synthesis, the antitumor activity, the SAR and, whenever described, the possible mode of action of 1,2,4-triazine derivatives, their N-oxides, N,. N'-dioxides as well as the benzo- and hetero-fused systems are reported. Herein are treated derivatives disclosed to literature from the beginning of this century up to 2016. Among the three possible triazine isomers, 1,2,4-triazines are the most studied ones and many derivatives having remarkable antitumor activity have been reported in the literature and also patented reaching advanced phases of clinical trials.
Effect of Methanolic Extract of Dandelion Roots on Cancer Cell Lines and AMP-Activated Protein Kinase Pathway
2017
Ethnomedicinal knowledge of plant-derived bioactives could help us in discovering new therapeutic compounds of great potential. Certainly, dandelion has been used in traditional ethno-medicinal systems (i.e., Chinese, Arabian, Indian, and Native American) to treat different types of cancer. Though, dandelion is highly vigorous, but the potential mode of action is still unclear. In the current study, the antiproliferative activity of methanolic extracts of dandelion root (MEDr) on cell viability of HepG2, MCF7, HCT116, and normal Hs27 was investigated. It was observed that MEDr (500 μg/mL) drastically decreased the growth of HepG2 cell line, while the effect on MCF7 and HCT116 cell lines was…
Evaluation of an amino acid residue critical for the specificity and activity of human Gb3/CD77 synthase
2016
Human Gb3/CD77 synthase (α1,4-galactosyltransferase) is the only known glycosyltransferase that changes acceptor specificity because of a point mutation. The enzyme, encoded by A4GALT locus, is responsible for biosynthesis of Gal(α1–4)Gal moiety in Gb3 (CD77, Pk antigen) and P1 glycosphingolipids. We showed before that a single nucleotide substitution c.631C > G in the open reading frame of A4GALT, resulting in replacement of glutamine with glutamic acid at position 211 (substitution p. Q211E), broadens the enzyme acceptor specificity, so it can not only attach galactose to another galactose but also to N-acetylgalactosamine. The latter reaction leads to synthesis of NOR antigens, which are…
Retinoic Acid affects Lung Adenocarcinoma growth by inducing differentiation via GATA6 activation and EGFR and Wnt inhibition
2016
AbstractA fundamental task in cancer research aims at the identification of new pharmacological therapies that can affect tumor growth. Differentiation therapy might exploit this function not only for hematological diseases, such as acute promyelocytic leukemia (APML) but also for epithelial tumors, including lung cancer. Here we show that Retinoic Acid (RA) arrests in vitro and in vivo the growth of Tyrosine Kinase Inhibitors (TKI) resistant Non Small Cell Lung Cancer (NSCLC). In particular, we found that RA induces G0/G1 cell cycle arrest in TKI resistant NSCLC cells and activates terminal differentiation programs by modulating the expression of GATA6, a key transcription factor involved …
Hepatitis delta virus infection in a large cohort of chronic hepatitis B patients in Ethiopia.
2017
Background Hepatitis D Virus (HDV)-infection is associated with a more severe outcome in patients with chronic hepatitis B (CHB); however, little is known about the presence of HDV in sub-Saharan Africa. We aimed to determine the prevalence of HDV-infection, as well as its clinical, biological and virological characteristics, in a large CHB cohort in Ethiopia. Methods In total, 1267 HIV-negative CHB patients at St. Paul's Hospital Millennium Medical College in Addis Ababa were screened for anti-HDV antibodies using ELISA assays. Confirmed positive samples were further tested for HDV RNA using a consensus commercial real-time RT-PCR assay. HDV genotypes were also determined for RNA positive …
Characterisation of a household norovirus outbreak occurred in Valencia (Spain)
2016
Background Human noroviruses (NoVs) are the main cause of non-bacterial gastroenteritis worldwide. Several studies have linked human susceptibility to NoVs with the expression of histo-blood group antigens (HBGAs). In January 2012, a NoV gastroenteritis outbreak affected a household in Valencia, Spain, and the personal susceptibility to NoV was investigated. Methods To reach this aim 8 members of the affected household were recruited for this study and their secretor status, ABO and Lewis antigens were determined. NoV-specific saliva IgA and serum IgG antibody titers were analyzed. Their capacity to block viral binding to saliva receptors was analyzed, using virus-like particles (VLPs) of t…
Boosting effect of IL-7 in interferon gamma release assays to diagnose Mycobacterium tuberculosis infection.
2018
BACKGROUND A quarter of the world's population is estimated to be infected with Myobacterium tuberculosis (Mtb). Infection is detected by immune response to M. tuberculosis antigens using either tuberculin skin test (TST) and interferon gamma release (IGRA's), tests which have low sensitivity in immunocompromised. IL-7 is an important cytokine for T-cell function with potential to augment cytokine release in in-vitro assays. This study aimed to determine whether the addition of IL-7 in interferon-gamma release assays (IGRAs) improves its diagnostic performance of Mtb infection. METHODS 44 cases with confirmed TB and 45 household contacts without TB were recruited and 1ml of blood was stimul…
Use of Medaka Fish as Vertebrate Model to Study the Effect of Cocoa Polyphenols in the Resistance to Oxidative Stress and Life Span Extension.
2018
Oxidative stress (OS) can induce cell apoptosis and thus plays an important role in aging. Antioxidant foods protect tissues from OS and contribute to a healthier lifestyle. In this study, we described the used of medaka embryos (Oryzias latipes) to study the putative antioxidant capacity of dietary cocoa extract in vertebrates. A polyphenol-enriched cocoa extract regulated the expression of several genes implicated in OS, thereby protecting fish embryos from induced OS. The cocoa extract activated superoxide dismutase enzyme activity in embryos and adult fish tissues, suggesting a common mechanism for protection during embryonic development and adulthood. Furthermore, long-term feeding of …
Cytotoxic effects of zearalenone and its metabolites and antioxidant cell defense in CHO-K1 cells.
2016
Zearalenone (ZEA) and its metabolites (α-zearalenol; α-ZOL, β-zearalenol; β-ZOL) are secondary metabolites of Fusarium fungi that produce cell injury. The present study explores mycotoxin-induced cell damage and cellular protection mechanisms in CHO-K1 cells. Cytotoxicity has been determined by reactive oxygen species (ROS) production and DNA damage. ROS production was determined using the fluorescein assay and DNA strand breakage by comet assay. Intracellular protection systems were glutathione (GSH), glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD). The results demonstrated that all mycotoxins increased the ROS levels up to 5.3-fold the control levels in CHO-K1 …
Ferric-bipyridine assay: A novel spectrophotometric method for measurement of antioxidant capacity
2020
Measurement of the antioxidant potential using in vitro assays is paramount in the assessment of various food products and nutraceuticals. Researchers always attempt to develop more accurate assays which can be performed in unsophisticated conditions. This novel method, Ferric-Bipyridine reducing capacity of total antioxidants (FBRC) is a very simple, accurate assay performed based on the reduction of Fe (III) to Fe (II) by antioxidants with the formation of a colored complex with bipyridine (Bp) i.e, Fe(II)-Bp. The FBRC method thus developed was assessed under carefully adjusted parameters of oxidant concentration, pH, temperature, solvent, light and time in order to fix the optimum condit…