Publications by authors named "Michael A Riel"

A randomized, double-blind, placebo-controlled study was conducted to assess the effect of tafenoquine, 200 mg weekly for 6 months on ophthalmic and renal safety. This trial was carried out after observations in previous clinical trials that tafenoquine may be associated with the development of corneal deposits and elevations in serum creatinine. In 120 healthy volunteers who received tafenoquine or placebo in a 2:1 randomization, there was no effect on night vision or other ophthalmic indices measured.

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Article Synopsis
  • Exposure to various chemicals, including pesticides and organophosphates, can alter ChE activity, making blood tests useful for diagnosing exposure and determining treatment options.
  • The Walter Reed Army Institute of Research (WRAIR) has developed a quicker, more efficient whole blood assay to measure both AChE and BChE activities without complex sample processing, which has been used in clinical trials to gather data on these enzymes' activities after drug administration.
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The substituted benzimidazoles omeprazole, lansoprazole, rabeprazole, and pantoprazole were found to have in vitro activity against three different isolates of Plasmodium falciparum: D6 (which is chloroquine and pyrimethamine sensitive), W2 (chloroquine and pyrimethamine resistant), and TM91C235 (multidrug resistant). Lansoprazole and rabeprazole were the most effective against all three isolates, with a 50% inhibitory concentration (IC(50)) range of 7 to 11 microM. Omeprazole showed intermediate activity against D6 and W2 isolates, with IC(50)s of 27 to 28 microM, but had poor activity against TM91C235, with an IC(50) of 76 microM.

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Scoparia dulcis is a perennial herb widely distributed in many tropical countries. It is used as an herbal remedy for gastrointestinal and many other ailments, and in Nicaragua extracts are used to treat malaria. Phytochemical screening has shown that scopadulcic acid A (SDA), scopadulcic acid B (SDB), and semisynthetic analogues are pharmacologically active compounds from S.

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