Search results for "Assay"
showing 10 items of 2241 documents
Development of an in vitro neuroblastoma 3D model and its application for sterigmatocystin-induced cytotoxicity testing
2021
Abstract Given the increasing importance of establishing better risk assessments for mycotoxins, novel in vitro tools for the evaluation of their toxicity are mandatory. In this study, an in vitro 3D spheroid model from SH-SY5Y cells, a human neuroblastoma cell line, was developed, optimized and characterized to test the cytotoxic effects caused by the mycotoxin sterigmatocystin (STE). STE induced a concentration- and time-dependent cell viability decrease in spheroids. Spheroids displayed cell disaggregation after STE exposure, increasing in a dose-dependent manner and over time. STE also induced apoptosis as confirmed by immunofluorescence staining and Western blot. Following the decrease…
Effects of anti-miR-182 on TSP-1 expression in human colon cancer cells: there is a sense in antisense?
2013
Abstract: Objective: miRNAs are attractive molecules for cancer treatment, including colon rectal cancer (CRC). We investigate on the molecular mechanism by which miR-182 could regulate thrombospondin-1 (TSP-1) expression, a protein down-regulated in CRC and inversely correlated with tumor vascularity and metastasis. Background: MicroRNAs are small non-coding RNAs that regulate the expression of different genes, involved in cancer progression, angiogenesis and metastasis. miR-182, over-expressed in colorectal cancer (CRC), has like predictive target thrombospondin-1 (TSP-1), a protein inversely correlated with tumor vascularity and metastasis that results downregulated in different types of…
The role of mitochondria in sterigmatocystin-induced apoptosis on SH-SY5Y cells
2020
Mitochondria are cellular organelles involved in many crucial functions, such as generation of energy (ATP) and initiation of apoptosis. The aim of the present study was to evaluate the role of mitochondria in the toxicity induced by sterigmatocystin (STE), a mycotoxin produced by fungi of the genus Aspergillus, on SH-SY5Y cells. Our results showed that STE exposure decreased cell viability in a time- and concentration-dependent manner by MTT assay and caused mitochondrial dysfunction, as highlighted by the increase of STE cytotoxicity in cells forced to rely on mitochondrial oxidative phosphorylation. Furthermore, intracellular ATP depletion and increased mitochondrial reactive oxygen spec…
APOPTOTIC ANALYSIS OF CUMULUS CELLS FOR THE SELECTION OF COMPETENT OOCYTES TO BE FERTILIZED BY INTRACYTOPLASMIC SPERM INJECTION (ICSI)
2015
Oocyte quality is one of the main factors for the success of in vitro fertilization protocols. Apoptosis is known to affect oocyte quality and may impair subsequent embryonic development and implantation. The aim of this study was to investigate the apoptosis rate of single and pooled cumulus cells of cumulus cell–oocyte complexes (COCs), as markers of oocyte quality, prior to intracytoplasmatic sperm injection (ICSI).We investigated the apoptosis rate by TUNEL assay (DNA fragmentation) and caspase-3 immunoassay of single and pooled cumulus cells of COCs. The results showed that DNA fragmentation in cumulus cells was remarkably lower in patients who achieved a pregnancy than in those who di…
Magnetic separation of encapsulated islet cells labeled with superparamagnetic iron oxide nano particles.
2012
Islet cell transplantation is a promising option for the restoration of normal glucose homeostasis in patients with type 1 diabetes. Because graft volume is a crucial issue in islet transplantations for patients with diabetes, we evaluated a new method for increasing functional tissue yield in xenogeneic grafts of encapsulated islets. Islets were labeled with three different superparamagnetic iron oxide nano particles (SPIONs; dextran-coated SPION, siloxane-coated SPION, and heparin-coated SPION). Magnetic separation was performed to separate encapsulated islets from the empty capsules, and cell viability and function were tested. Islets labeled with 1000 μg Fe/ml dextran-coated SPIONs expe…
Bioassays for TSH Receptor Antibodies: Quo Vadis?
2015
Autoantibodies (Ab) to the TSH receptor (TSHR) are responsible for many of the clinical manifestations of Graves' disease (GD) and are specific biomarkers of this autoimmune thyroid disorder (AITD) [1,2,3]. These Ab can be measured either via competitive-binding immunoassays or with bioassays [4]. Antibody-binding assays only report the presence or absence of TSHR-Ab and their concentrations, but do not indicate their functional activity. Bioassays, in contrast, indicate whether TSHR-Ab have stimulatory or blocking activity [5]. Historically, bioassays for TSHR-Ab were research tools used to study the pathophysiology of GD. Recently, however, there are increasing data that demonstrate the c…
Nuclear receptor NR5A2 and bone: gene expression and association with bone mineral density
2011
El pdf del artículo es el manuscrito de autor (PMCID: PMC3682472).-- et al.
Standardization of a bioassay for thyrotropin receptor stimulating autoantibodies.
2015
Cell-based bioassays for functional thyroid stimulating autoantibodies (TSAb) are sensitive diagnostic tools. However, there is no bioassay available that is standardized with international reference material. We aimed to promote the standardization of the test results among laboratories that perform TSAb bioassays and calibrate TSAb levels against the second international standard (IS) 08/204 from the National Institute for Biological Standards and Control (NIBSC).Serum TSAb activity was measured with a FDA-cleared bioassay that utilizes CHO cells expressing a chimeric thyrotropin receptor (TSHR) and a c-AMP response-element-dependent luciferase. The IS was applied for calibration. TSAb re…
A Novel Long-Term Graves’ Disease Animal Model Confirmed by Functional Thyrotropin Receptor Antibodies
2020
<b><i>Introduction:</i></b> A novel long-term murine model for Graves’ disease (GD) using repeated, long-term immunizations with recombinant adenovirus expressing the extracellular A-subunit of the human thyrotropin receptor (Ad-TSHR) was applied to evaluate the functional anti-TSHR-antibody (TSHR-Ab) profile. <b><i>Methods:</i></b> BALB/c mice received 7 immunizations with either 10<sup>10</sup> plaque-forming units of Ad-TSHR or control Ad-GFP. Naïve (nonimmuized native) mice were also studied. Three 3-weekly immunizations were followed by 4-weekly boosts until the 7th immunization. Blocking (TBAb) and stimulating (TSAb) TSHR-Ab …
Cilium induction triggers differentiation of glioma stem cells.
2020
Glioblastoma multiforme (GBM) possesses glioma stem cells (GSCs) that promote self-renewal, tumor propagation, and relapse. Understanding the mechanisms of GSCs self-renewal can offer targeted therapeutic interventions. However, insufficient knowledge of GSCs' fundamental biology is a significant bottleneck hindering these efforts. Here, we show that patient-derived GSCs recruit elevated levels of proteins that ensure the temporal cilium disassembly, leading to suppressed ciliogenesis. Depleting the cilia disassembly complex components is sufficient to induce ciliogenesis in a subset of GSCs via relocating platelet-derived growth factor receptor-alpha (PDGFR-α) to a newly induced cilium. Im…