Search results for "Assay"
showing 10 items of 2241 documents
Epidemiological study ofCryptosporidium parvum in sera of persons from Germany
1998
In a seroprevalence study including 495 sera from persons of all age-groups, the presence of anti-Cryptosporidium parvum antibodies was evaluated in an enzyme immunoassay. Despite the fact that C. parvum is only found in approximately 2% of patients with diarrhea in Germany, specific antibodies could be detected in 15.4% of all samples. This figure indicates that a substantial proportion of the German population has been confronted with this parasite and it raises the question of whether C. parvum is a potential health risk to the general population.
EMPLOYMENT OF CATIONIC SOLID-LIPID NANOPARTICLES AS RNA CARRIERS
2007
Gene transfer represents an important advance in the treatment of both genetic and acquired diseases. In this article, the suitability of cationically modified solid-lipid nanoparticles (SLN) as a nonviral vector for gene delivery was investigated, in order to obtain stable materials able to condense RNA. Cationic SLN were produced by microemulsion using Compritol ATO 888 as matrix lipid, Pluronic F68 as tenside, and dimethyldioctadecylammonium bromide (DDAB) as cationic lipid. The resulting particles were approximately 100 nm in size and showed a highly positive surface charge (+41 mV) in water. Size and shape were further characterized by scanning electron microscopy (SEM) measurements. M…
Pursaethosides A-E, triterpene saponins from Entada pursaetha.
2005
Five new triterpenoid saponins, pursaethosides A-E (1-5), were isolated from the n-BuOH extract of the seed kernels of Entada pursaetha along with the known phaseoloidin. The structures of 1-5 were elucidated mainly by spectroscopic data interpretation and chemical degradation. Pursaethosides C-E (3-5) possess as a common structural feature entagenic acid as aglycon, which is rare among triterpene saponins. Compounds 2-4 and phaesolidin were found to be not cytotoxic when tested against HCT 116 and HT-29 human colon cancer cells.
Biocompatibility of Mineral Trioxide Aggregate with TiO2 Nanoparticles on Human Gingival Fibroblasts
2016
Background The New compositions of white mineral trioxide aggregate (WMTA) or use of various additives like nanoparticles might affect MTA’s ideal characteristics This study was performed to evaluate the cytotoxicity of WMTA and WMTA with Titanium dioxide (TiO2) nanoparticles (1% weight ratio) at different storage times after mixing on human gingival fibroblasts (HGFs). Material and Methods HGFs were obtained from the attached gingiva of human premolars. HGFs were cultured in Dulbecco’s Modified Eagle medium, supplemented with 10% fetal calf serum, penicillin and streptomycin. The cells were exposed to WMTA (groups 1 and 2) and WMTA+TiO2 (groups 3 and 4). The fifth and sixth groups served a…
Biocompatibility of three new calcium silicate-based endodontic sealers on human periodontal ligament stem cells.
2016
Aim To evaluate the biocompatibility of three calcium silicate-based endodontic sealers, Bioroot BC Sealer (Septodont, Saint-Maur-des-Fosses, France), Endoseal MTA (EndoSeal, Maruchi, Seoul, Korea) and Nano-ceramic Sealer (B&L Biotech, Fairfax, VA, USA) (NCS), on human periodontal ligament stem cells (hPDLSCs). Methodology Human periodontal ligament stem cells were cultured in the presence of various endodontic sealer eluates for 24 h. Cell viability was determined using the MTT assay. Cell death and changes in phenotype induced by the set endodontic sealer eluates were evaluated through flow cytometry. Also, an in vitro scratch wound-healing model was used to determine their effects in cel…
Synthesis, cytotoxicity, and inhibitory effects on tubulin polymerization of a new 3-heterocyclo substituted 2-styrylquinazolinones
2004
In order to study the influence of 3-substitution on the cytotoxic activity of 2-styrylquinazolinones, new 6-chloro-2-styryl-3-(heteroaryl)-4(3H)-quinazolinones were synthesized by refluxing equimolar amounts of 6-chloro-2-methyl-3-(heteroaryl)-4(3H)-quinazolinones and benzaldehyde in glacial acetic acid. At 1 microg ml(-1) concentration, almost all 2-styrylquinazolinones showed some cytotoxic activity against the L1210 and K562 leukemia cell lines. However, only 6-chloro-2-styryl-3-(pyrimidin-2yl)-4(3H)-quinazolinone inhibited the growth of these cells by over 50%. This last compound was also the only member of the series that inhibited tubulin polymerization, with an IC(50) value of 5.8 v…
Isoindolo[2,1-a]quinoxaline derivatives, novel potent antitumor agents with dual inhibition of tubulin polymerization and topoisomerase I.
2008
Isoindoloquinoxalines 4 and 5 were obtained by refluxing 2-(2'-aminoaryl)-1-cyanoisoindoles 3a- e in acetic or formic acid. All derivatives were screened by the National Cancer Institute (Bethesda, MD) for the in vitro one dose primary anticancer assay against a 3-cell line panel. Compounds 4a- e, screened against a panel of about 60 human tumor cell lines, showed remarkable antineoplastic activity; they had GI 50 values in the low micromolar or submicromolar range and reached, in the case of 4c, nanomolar concentrations on 88% of the 59 tested cell lines. Flow cytometric analysis of cell cycle after treatment with 4c demonstrated an arrest of the cell cycle in G2/M phase. This effect was a…
The inorganic polymer, polyphosphate, blocks binding of SARS-CoV-2 spike protein to ACE2 receptor at physiological concentrations
2020
Graphical abstract The inorganic physiological polymer, polyphosphate, blocks binding of SARS-CoV-2 spike protein to ACE2 receptor at physiological concentrations. This discovery proposes polyphosphate as a new member of the host's antiviral innate immune defense.
A novel rat CVB1-VP1 monoclonal antibody 3A6 detects a broad range of enteroviruses
2018
AbstractEnteroviruses (EVs) are common RNA viruses that cause diseases ranging from rash to paralytic poliomyelitis. For example, EV-A and EV-C viruses cause hand-foot and mouth disease and EV-B viruses cause encephalitis and myocarditis, which can result in severe morbidity and mortality. While new vaccines and treatments for EVs are under development, methods for studying and diagnosing EV infections are still limited and therefore new diagnostic tools are required. Our aim was to produce and characterize new antibodies that work in multiple applications and detect EVs in tissues and in vitro. Rats were immunized with Coxsackievirus B1 capsid protein VP1 and hybridomas were produced. Hybr…
Synthesis, Structural Elucidation, and Biological Evaluation of NSC12, an Orally Available Fibroblast Growth Factor (FGF) Ligand Trap for the Treatme…
2016
NSC12 is an orally available pan-FGF trap able to inhibit FGF2/FGFR interaction and endowed with promising antitumor activity. It was identified by virtual screening from a NCI small molecule library, but no data were available about its synthesis, stereochemistry, and physicochemical properties. We report here a synthetic route that allowed us to characterize and unambiguously identify the structure of the active compound by a combination of NMR spectroscopy and in silico conformational analysis. The synthetic protocol allowed us to sustain experiments aimed at assessing its therapeutic potential for the treatment of FGF-dependent lung cancers. A crucial step in the synthesis generated a c…