Search results for "DISCOVERY"

Application of a portable instrument for rapid and reliable detection of SARS-CoV-2 infection in any environment

2020

Abstract The ongoing outbreak of the novel coronavirus (SARS‐CoV‐2) infection is creating serious challenges for health laboratories that seek to identify viral infections as early as possible, optimally at the earliest appearance of symptom. Indeed, there is urgent need to develop and deploy robust diagnostic methodologies not only to use in health laboratory environments but also directly in places where humans circulate and spread the virus such as airports, trains, boats, and any public aggregation places. The success of a reliable and sensitive asymptomatic diagnosis relies on the identification and measurement of informative biomarkers from human host and virus in a rapid, sensitive, …

Tumor Heterogeneity, Single-Cell Sequencing, and Drug Resistance

2016

Tumor heterogeneity has been compared with Darwinian evolution and survival of the fittest. The evolutionary ecosystem of tumors consisting of heterogeneous tumor cell populations represents a considerable challenge to tumor therapy, since all genetically and phenotypically different subpopulations have to be efficiently killed by therapy. Otherwise, even small surviving subpopulations may cause repopulation and refractory tumors. Single-cell sequencing allows for a better understanding of the genomic principles of tumor heterogeneity and represents the basis for more successful tumor treatments. The isolation and sequencing of single tumor cells still represents a considerable technical ch…

Antiprotozoal and cysteine proteases inhibitory activity of dipeptidyl enoates

2018

A family of dipeptidyl enoates has been prepared and tested against the parasitic cysteine proteases rhodesain, cruzain and falcipain-2 related to sleeping sickness, Chagas disease and malaria, respectively. They have also been tested against human cathepsins B and L1 for selectivity. Dipeptidyl enoates resulted to be irreversible inhibitors of these enzymes. Some of the members of the family are very potent inhibitors of parasitic cysteine proteases displaying k2nd (M−1s−1) values of seven orders of magnitude. In vivo antiprotozoal testing was also performed. Inhibitors exhibited IC50 values in the micromolar range against Plasmodium falciparum, Trypanosoma brucei, Trypanosoma cruzi and ev…

In Vivo Cardiotoxicity Induced by Sodium Aescinate in Zebrafish Larvae

2016

Sodium aescinate (SA) is a widely-applied triterpene saponin product derived from horse chestnut seeds, possessing vasoactive and organ-protective activities with oral or injection administration in the clinic. To date, no toxicity or adverse events in SA have been reported, by using routine models (in vivo or in vitro), which are insufficient to predict all aspects of its pharmacological and toxicological actions. In this study, taking advantage of transparent zebrafish larvae (Danio rerio), we evaluated cardiovascular toxicity of SA at doses of 1/10 MNLC, 1/3 MNLC, MNLC and LC10 by yolk sac microinjection. The qualitative and quantitative cardiotoxicity in zebrafish was assessed at 48 h p…

New Thiazole Nortopsentin Analogues Inhibit Bacterial Biofilm Formation.

2018

New thiazole nortopsentin analogues were conveniently synthesized and evaluated for their activity as inhibitors of biofilm formation of relevant Gram-positive and Gram-negative pathogens. All compounds were able to interfere with the first step of biofilm formation in a dose-dependent manner, showing a selectivity against the staphylococcal strains. The most active derivatives elicited IC50 values against Staphylococcus aureus ATCC 25923, ranging from 0.40&ndash

Analysis of the Transcriptome of the Red Seaweed Grateloupia imbricata with Emphasis on Reproductive Potential

2018

Grateloupia imbricata is an intertidal marine seaweed and candidate model organism for both industry and academic research, owing to its ability to produce raw materials such as carrageenan. Here we report on the transcriptome of G. imbricata with the aim of providing new insights into the metabolic pathways and other functional pathways related to the reproduction of Grateloupia species. Next-generation sequencing was carried out with subsequent de novo assembly and annotation using state-of-the-art bioinformatic protocols. The results show the presence of transcripts required for the uptake of glycerol, which is a specific carbon source for in vitro culture of G. imbricata and nucleotide …

Synthesis and cytotoxic activity of new artemisinin hybrid molecules against human leukemia cells

2017

A series of new artemisinin-derived hybrids which incorporate cholic acid moieties have been synthesized and evaluated for their antileukemic activity against sensitive CCRF-CEM and multidrug-resistant CEM/ADR5000 cells. The new hybrids 20-28 showed IC50 values in the range of 0.019µM-0.192µM against CCRF-CEM cells and between 0.345µM and 7.159µM against CEM/ADR5000 cells. Amide hybrid 25 proved the most active compound against both CCRF-CEM and CEM/ADR5000 cells with IC50 value of 0.019±0.001µM and 0.345±0.031µM, respectively. A relatively low cross resistance to hybrids 20-28 in the range of 5.7-fold to 46.1-fold was measured. CEM/ADR5000 cells showed higher resistance than CCRF-CEM to al…

A Bimolecular Multicellular Complementation System for the Detection of Syncytium Formation: A New Methodology for the Identification of Nipah Virus …

2019

Fusion of viral and cellular membranes is a key step during the viral life cycle. Enveloped viruses trigger this process by means of specialized viral proteins expressed on their surface, the so-called viral fusion proteins. There are multiple assays to analyze the viral entry including those that focus on the cell-cell fusion induced by some viral proteins. These methods often rely on the identification of multinucleated cells (syncytium) as a result of cell membrane fusions. In this manuscript, we describe a novel methodology for the study of cell-cell fusion. Our approach, named Bimolecular Multicellular Complementation (BiMuC), provides an adjustable platform to qualitatively and quanti…

2021

The biological activities of shancigusin C (1) and bletistrin G (2), natural products isolated from orchids, are reported along with their first total syntheses. The total synthesis of shancigusin C (1) was conducted by employing the Perkin reaction to forge the central stilbene core, whereas the synthesis of bletistrin G (2) was achieved by the Wittig olefination followed by several regioselective aromatic substitution reactions. Both syntheses were completed by applying only renewable starting materials according to the principles of xylochemistry. The cytotoxic properties of shancigusin C (1) and bletistrin G (2) against tumor cells suggest suitability as a starting point for further str…

Topographical geometric factors governing the biological activities of methomyl derivatives on binding receptors of maize mitochondria

1986

Abstract The topographical study of the binding receptors of T and N mitochondria was undertaken with methomyl derivatives acting as molecular probes. The two biological activities related to topography and geometric isomerism are distinguishable from the receptor sites of T and N mitochondria.