Publications by authors named "Ibrahim A Alfayez"

Ten compounds, six extracts and five fractions obtained from three Nigerian plants were assayed for their in vitro antitrypanosomal and antileishmanial activities. Each plant was extacted with hexane, ethyl acetate, and methanol. Isolated compounds were characterized and identified based on their NMR chemical shifts and comparison to literature reports.

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Among the scarce validated drug targets against Chagas disease (CD), caused by , the parasite's nucleoside salvage system has recently attracted considerable attention. Although the trypanocidal activity of tubercidin (7-deazapurine) has long been known, the identification of a class of 7-substituted tubercidin analogs with potent in vitro and in vivo activity and much-enhanced selectivity has made nucleoside analogs among the most promising lead compounds against CD. Here, we investigate the recently identified TcrNT2 nucleoside transporter and its potential role in antimetabolite chemotherapy.

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The study of transporters is highly challenging, as they cannot be isolated or studied in suspension, requiring a cellular or vesicular system, and, when mediated by more than one carrier, difficult to interpret. Nucleoside analogues are important drug candidates, and all protozoan pathogens express multiple equilibrative nucleoside transporter (ENT) genes. We have therefore developed a system for the routine expression of nucleoside transporters, using CRISPR/cas9 to delete both copies of all three nucleoside transporters from (ΔNT1.

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Ethanolic extracts of samples of temperate zone propolis, four from the UK and one from Poland, were tested against three strains and displayed EC values < 20 µg/mL. The extracts were fractionated, from which 12 compounds and one two-component mixture were isolated, and characterized by NMR and high-resolution mass spectrometry, as 3-acetoxypinobanksin, tectochrysin, kaempferol, pinocembrin, 4'-methoxykaempferol, galangin, chrysin, apigenin, pinostrobin, cinnamic acid, coumaric acid, cinnamyl ester/coumaric acid benzyl ester (mixture), 4',7-dimethoxykaempferol, and naringenin 4',7-dimethyl ether. The isolated compounds were tested against drug-sensitive and drug-resistant strains of and , with the highest activities ≤ 15 µM.

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We have recently reported on the development and trypanocidal activity of a class of inhibitors of Trypanosome Alternative Oxidase (TAO) that are targeted to the mitochondrial matrix by coupling to lipophilic cations via C14 linkers to enable optimal interaction with the enzyme's active site. This strategy resulted in a much-enhanced anti-parasite effect, which we ascribed to the greater accumulation of the compound at the location of the target protein, i.e.

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Human African trypanosomiasis is a neglected tropical disease caused by parasites. These protists are unable to produce the purine ring, making them vulnerable to the effects of purine nucleoside analogues. Starting from 3'-deoxytubercidin (), a lead compound with activity against central-nervous-stage human African trypanosomiasis, we investigate the structure-activity relationships of the purine and ribofuranose rings.

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African trypanosomiasis, a deadly infectious disease caused by the protozoan Trypanosoma brucei spp., is spread to new hosts by bites of infected tsetse flies. Currently approved therapies all have their specific drawbacks, prompting a search for novel therapeutic agents.

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Synopsis of recent research by authors named "Ibrahim A Alfayez"

  • - Recent research by Ibrahim A Alfayez focuses on the development of antitrypanosomal and antileishmanial agents derived from various natural sources, particularly emphasizing the biological activity of compounds extracted from Nigerian plants and temperate propolis.
  • - His studies include investigating nucleoside transport mechanisms in protozoan pathogens, identifying the role of transporters in drug uptake, and exploring structure-activity relationships of nucleoside analogs as promising leads for treating Chagas disease and African trypanosomiasis.
  • - Alfayez has also worked on synthesizing fluorescent inhibitors targeting Trypanosome Alternative Oxidase, advancing strategies for enhancing drug efficacy through improved localization of therapeutic agents within the parasite's cellular structures.

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