Ricardo Calhelha

Dr. Ricardo Calhelha

Instituto Politecnico de Braganca, Braganca, Portugal
orcid

Research Focus & Metrics

Academic Career Length

23Years (2004-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 October 2013 in Journal of Functional Foods
Verified
Journal Article
Closed access
Lillian BarrosLillian Barros
Lillian Barros
Eliana PereiraEliana Pereira
Eliana Pereira
Ricardo CalhelhaRicardo Calhelha
Ricardo Calhelha
MDMontserrat Dueñas
Montserrat Dueñas
Ana Maria CarvalhoAna Maria Carvalho
Ana Maria Carvalho
Isabel FerreiraIsabel Ferreira
Isabel Ferreira

15 November 2022 in Polymers
Verified
Journal Article
Open access
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ASAndreia S. Silva
Andreia S. Silva
ECElisabete C. Costa
Elisabete C. Costa
Sara ReisSara Reis
Sara Reis
CSCarina Spencer
Carina Spencer
Ricardo CalhelhaRicardo Calhelha
Ricardo Calhelha
PCPaula Coutinho
Paula Coutinho
Silk is a natural composite fiber composed mainly of hydrophobic fibroin and hydrophilic sericin, produced by the silkworm Bombyx mori. In the textile industry, the cocoons of B. mori are processed into silk fabric, where the sericin is substantially removed and usually discarded in wastewater. This wastewater pollutes the environment and water sources. However, sericin has been recognized as a potential biomaterial due to its biocompatibility, immunocompatibility, biodegradability, anti-inflammatory, antibacterial, antioxidant and photoprotective properties. Moreover, sericin can produce hydrogels, films, sponges, foams, dressings, particles, fibers, etc., for various biomedical and pharmaceutical applications (e.g., tissue engineering, wound healing, drug delivery, cosmetics). Given the severe environmental pollution caused by the disposal of sericin and its beneficial properties, there has been growing interest in upcycling this biomaterial, which could have a strong and positive economic, social and environmental impact.

13 June 2006 in European Food Research and Technology
Verified
Journal Article
Closed access
PDF file
Lillian BarrosLillian Barros
Lillian Barros
Ricardo CalhelhaRicardo Calhelha
Ricardo Calhelha
Josiana VazJosiana Vaz
Josiana Vaz
Isabel FerreiraIsabel Ferreira
Isabel Ferreira
Paula BaptistaPaula Baptista
Paula Baptista
Leticia M. EstevinhoLeticia M. Estevinho
Leticia M. Estevinho


1 October 2015 in Bioorganic & Medicinal Chemistry
Verified
Journal Article
Open access
VMVera Machado
Vera Machado
DPDaniela Peixoto
Daniela Peixoto
Raquel CostaRaquel Costa
Raquel Costa
HFHugo J.C. Froufe
Hugo J.C. Froufe
Ricardo CalhelhaRicardo Calhelha
Ricardo Calhelha
MQMaria-João Queiroz
Maria-João Queiroz
The synthesis and biological evaluation of novel 1-aryl-3-[2-, 3- or 4-(thieno[3,2-b]pyridin-7-ylthio)phenyl]ureas 3, 4 and 5 as VEGFR-2 tyrosine kinase inhibitors, are reported. The 1-aryl-3-[3-(thieno[3,2-b]pyridin-7-ylthio)phenyl]ureas 4a-4h, with the arylurea in the meta position to the thioether, showed the lowest IC₅₀ values in enzymatic assays (10-206 nM), the most potent compounds 4d-4h (IC₅₀ 10-28 nM) bearing hydrophobic groups (Me, F, CF₃ and Cl) in the terminal phenyl ring. A convincing rationalization was achieved for the highest potent compounds 4 as type II VEGFR-2 inhibitors, based on the simultaneous presence of: (1) the thioether linker and (2) the arylurea moiety in the meta position. For compounds 4, significant inhibition of Human Umbilical Vein Endothelial Cells (HUVECs) proliferation (BrdU assay), migration (wound-healing assay) and tube formation were observed at low concentrations. These compounds have also shown to increase apoptosis using the TUNEL assay. Immunostaining for total and phosphorylated (active) VEGFR-2 was performed by Western blotting. The phosphorylation of the receptor was significantly inhibited at 1.0 and 2.5 μM for the most promising compounds. Altogether, these findings point to an antiangiogenic effect in HUVECs.