Evaluation of the Clearview® malaria pLDH malaria rapid diagnostic test in a non-endemic setting

<p>Abstract</p> <p>Background</p> <p>Malaria Rapid Diagnostic Tests (RDTs) are widely used to diagnose malaria. The present study evaluated a new RDT, the Clearview^®Malaria pLDH test targeting the pan-<it>Plasmodium </it>antigen lactate dehydrogenase (pLDH).</p> <p>Methods</p> <p>The Clearview^®Malaria pLDH test was evaluated on fresh samples obtained in returned international travellers using microscopy corrected by PCR as the reference method. Included samples were <it>Plasmodium falciparum </it>(139), <it>Plasmodium vivax </it>(22), <it>Plasmodium ovale </it>(20), <it>Plasmodium malariae </it>(7), and 102 negative.</p> <p>Results</p> <p>Overall sensitivity for the detection of <it>Plasmodium </it><it>spp </it>was 93.2%. For <it>P. falciparum</it>, the sensitivity was 98.6%; for <it>P. vivax</it>, <it>P. ovale </it>and <it>P. malariae</it>, overall sensitivities were 90.9%, 60.0% and 85.7% respectively. For <it>P. falciparum </it>and for <it>P. vivax</it>, the sensitivities increased to 100% at parasite densities above 100/μl. The specificity was 100%. The test was easily to perform and the result was stable for at least 1 hour.</p> <p>Conclusion</p> <p>The Clearview^®Malaria pLDH was efficient for the diagnosis of malaria. The test was very sensitive for <it>P. falciparum </it>and <it>P. vivax </it>detection. The sensitivities for <it>P. ovale </it>and <it>P. malariae </it>were better than other RDTs</p

Lack of association between putative transporter gene polymorphisms in Plasmodium falciparum and chloroquine resistance in imported malaria isolates from Africa

BACKGROUND: Plasmodium falciparum drug resistance represents a major health problem in malaria endemic countries. The mechanisms of resistance are not fully elucidated. Recently, an association between putative transporter gene polymorphisms and in vitro response to chloroquine (CQ) and quinine has been reported in culture-adapted, cloned isolates from various geographical origins. However, this was not confirmed in another study performed on isolates from a defined region in Thailand. METHODS: This study tried to find an association between putative transporters gene polymorphisms with in vitro response to CQ and pfcrt genotype in isolates originating from various African countries. To avoid biases of parasites adaptation in culture, fresh isolates obtained from symptomatic, malaria-infected travellers returning from Africa to France were used. Monoclonal isolates included in the study were selected using a msp-2 fragment analysis method. In vitro susceptibility to CQ, single nucleotide polymorphisms and microsatellite polymorphisms in pfcrt, pfmdr1 and six putative transporter genes were established in 27 isolates and three reference strains. RESULTS: Polymorphism of pfcrt at positions 76 and 220 showed a significant association with in vitro chloroquine resistance (P < .02 and P < .05 respectively). Polymorphism of pfmdr1 at position 86 showed an equally significant association with in vitro chloroquine response (P < .05). No association was found between SNPs or microsatellite polymorphisms of putative transporter genes and in vitro CQR or pfcrt genotype in imported malaria isolates from Africa. CONCLUSION: The previously described association between putative transporter gene polymorphisms and in vitro response to chloroquine (CQ) was not confirmed in the present study

Antifungal potential of extracts from three plants against two major pathogens of celery (apium graveolens l.) in Cameroon

With the aim of contributing to natural control of plant pathogens, the antifungal activity of 11 extracts from 3 Cameroonian plants namely, Drypetes gossweileri, Eucalyptus tereticornis and Sida acuta was evaluated against Acremonium apii and Colletotrichum dematium, respectively causal agents of brown spot and anthracnose diseases of celery (Apium graveolens L.). The supplemented media technique was used to assess the inhibition of both fungi mycelial growth by essential oils, ethanol,hot water and cold water extracts. The essential oils exhibited the highest antifungal activity at 50 ppm with essential oil from D. gossweileri; and 6000 ppm and 7000 ppm, against C. dematium and A. apii, respectively, with essential oil from E. tereticornis. Ethanol and aqueous extracts displayed a moderate inhibitory activity with the best activity obtained from D. gossweileri ethanol extracts (90.31% and 67.53%, respectively, against A. apii and C. dematium at 10000 ppm). The fungitoxic potential of essential oils was comparative to the synthetic fungicide used as positive control. Phytochemical screening of solvent extracts revealed a diverse composition in secondary metabolites and stronger inhibitory effects were recorded with extracts rich in alkaloids, phenols, anthraquinones and saponines. These findings suggest a promising potential of essential oils and ethanol extracts for botanicals control of celery fungal pathogens