BACKGROUND Artemisinin-induced dormancy provides a plausible explanation for recrudescence following artemisinin monotherapy. This phenomenon shares similarities with cell cycle arrest where cyclin dependent kinases (CDKs) and cyclins play an important role. METHODS Transcription profiles of Plasmodium falciparum CDKs and cyclins before and after dihydroartemisinin (DHA) treatment in three pa...

In nature Siberian hamsters utilize the decrement in day length following the summer solstice to implement physiological adaptations in anticipation of the forthcoming winter, but also exploit an intrinsic interval timer to initiate physiological recrudescence following the winter solstice. However, information is lacking on the temporal dynamics in natural photoperiod of photoperiodically regu...

The aim of this study was to find out if reinfection or recrudescence accounted for the recurrence of Helicobacter pylori infections after apparent eradication of the bacterium. Three hundred and twenty patients were treated with colloidal bismuth subcitrate (120 mg four times daily for four weeks), metronidazole and tetracycline (400 mg and 500 mg, respectively, thrice daily for the first week...

This study analyzed photoperiodic sensitivity of brahminy myna (Sturnus pagodarum), which is a seasonally breeding bird species. During regression phase of the reproductive cycle (in early September), groups of myna were exposed to artificial photoperiods that were either close to or longer than those brahminy myna experiences at this time in wild at 29 degrees N. Following a 14-week exposure t...

We assessed the efficacy of trimethoprim/sulfamethoxazole (TRM/SMX) in vivo in relation to the frequency of dihydrofolate reductase (dhfr) and dihydropteroate synthase (dhps) alleles in 45 Sudanese malaria patients. Plasma levels of TRM, SMX, and acetylsulfamethoxazole (AcSMX) were measured before treatment and at days 3, 7, and 14 or upon recrudescence to ascertain drug absorption. Forty patie...

Plasmodium spp. protozoa cause malaria and are known to infect humans and a variety of animal species including macaque monkeys. Here we report both our experience with malaria recrudescence in cynomolgus monkeys (Macaca fascicularis) in a toxicity study and the results of a survey on Plasmodium infection in cynomolgus monkeys imported to Japan for laboratory use. A cynomolgus monkey from the t...

CD8(+) T cells are required to control acute viral replication in the CNS following infection with neurotropic coronavirus. By contrast, studies in B cell-deficient (muMT) mice revealed Abs as key effectors in suppressing virus recrudescence. The apparent loss of initial T cell-mediated immune control in the absence of B cells was investigated by comparing T cell populations in CNS mononuclear ...

OBJECTIVES OZ439, or artefenomel, is an investigational synthetic ozonide antimalarial with similar potency, but a significantly improved pharmacokinetic profile, compared with artemisinins. We wished to measure key pharmacokinetic and pharmacodynamic parameters and the pharmacokinetic/pharmacodynamic relationship of artefenomel in humans to guide the drug's further development as combination t...

This study examined whether reinfection or recrudescence accounts for the reappearance of Helicobacter pylori infection after apparent successful eradication. In a prospective study, 173 patients cured from H. pylori infection underwent follow-up endoscopies, with biopsies for culture and histopathology, every 3 months during the first year after treatment. Subsequently, elective half-yearly en...

The mid-winter development of refractoriness to melatonin (Mel) triggers recrudescence of the atrophied reproductive apparatus of rodents. As a consequence, over-wintering animals become reproductively competent just before the onset of spring conditions favorable for breeding. The neural target tissues that cease to respond to winter Mel signals have not been identified. We now report that the...