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Mohammad Fawad Ansari Faisal Hayat Afreen Inam Fatima Kathrada Robyn L. van Zyl Maureen Coetzee Kamal Ahmad Dongyun Shin Amir Azam 《Bioorganic & medicinal chemistry letters》2017,27(3):460-465
In an endeavor to develop efficacious antiprotozoal agents 4-(7-chloroquinolin-4-yl) piperazin-1-yl)pyrrolidin-2-yl)methanone derivatives (5–14) were synthesized, characterized and biologically evaluated for antiprotozoal activity. The compounds were screened in vitro against the HM1: IMSS strain of Entamoeba histolytica and NF54 chloroquine-sensitive strain of Plasmodium falciparum. Among the synthesized compounds six exhibited promising antiamoebic activity with IC50 values (0.14–1.26 μM) lower than the standard drug metronidazole (IC50 1.80 μM). All nine compounds exhibited antimalarial activity (IC50 range: 1.42–19.62 μM), while maintaining a favorable safety profile to host red blood cells. All the compounds were less effective as an antimalarial and more toxic (IC50 range: 14.67–81.24 μM) than quinine (IC50: 275.6 ± 16.46 μM) against the human kidney epithelial cells. None of the compounds exhibited any inhibitory effect on the viability of Anopheles arabiensis mosquito larvae. 相似文献
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Georgia Pacheco Rachel Fatima Gagliardi Leonardo Alves Carneiro José Francisco Montenegro Valls Elisabeth Mansur 《In vitro cellular & developmental biology. Plant》2008,44(1):14-17
Seed explants of A. stenosperma were cultured on MS medium supplemented with 6-benzylaminopurine with the aim of rescuing nonviable accessions stored in
seed bank conditions. The regeneration potential of leaf explants from in vitro plants derived from embryonic axes was studied by using whole leaflets and leaflet segments. Explants were cultured on Murashige
and Skoog (MS) medium supplemented with different concentrations of 6-benzylaminopurine and naphthalene acetic acid. Indirect
organogenesis was observed in response to 6-benzylaminopurine, either alone or in association with naphthalene acetic acid,
in both explant types. Media supplemented with naphthalene acetic acid as the sole growth regulator induced rhizogenesis in
whole leaflets and leaflet segments, with subsequent shoot production directly from the roots. 相似文献
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Keyhole limpet hemocyanin (KLH)-conjugated peptides are routinely used to raise polyclonal antibodies for biochemical or immunolocalization studies. Rats are suitable for producing antisera against plant antigens as they often lack non-specific response towards plant materials. We attempted to obtain rat antisera against peptides derived from several plant proteins. However, most antisera recognized the same background KLH-related plant antigen (KRAP) in Arabidopsis and tobacco. We characterized KRAP with respect to size and cellular localization and examined possible antigen-specific reasons for the failure of most immunizations. We also found no reports of successful use of rat anti-KLH-peptide antibodies in plant studies. We thus believe that the rat-KLH:peptide system is poorly suited for production of antibodies, especially against plant antigens, and should be used with caution, if at all. 相似文献