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The EUREQUA project raises the issue of the definition and evaluation of the environmental quality of neighbourhoods. The approach consists of integrating and cross-referencing observable data characterising the physical environment and people's perception of their quality of life. The study area is a neighbourhood in Toulouse (France) with high social and typo-morphological diversity, subject to noise and air pollution nuisances. Three 3-day field campaigns were organised in January, April, and June 2014. Instrumented and commented walks took place three times per day. For each one, measurements of physical environmental parameters and surveys were performed simultaneously at six locations in the neighbourhood. The study focuses on microclimate and thermal comfort issues. It aims to compare in situ meteorological data of air temperature, humidity, wind speed, and mean radiant temperature, with quantitative results rating human perception of heat, humidity, wind, and thermal comfort. The variability in perception and measurements is mainly driven by seasonal effects, especially for heat and humidity, and, to a lesser extent, for wind. Wind perception and measurement also vary spatially, thus highlighting site effects. Linear models indicate a positive link between heat perception and mean radiant temperature, as well as between wind perception and mean and standard deviation of wind speed (with a higher sensitivity of people to wind under winter climate conditions). Finally, it is found that perception of thermal comfort is only slightly linked to the different microclimate dimensions, and is rather driven by other appreciation factors and emotional criteria related to the general environmental quality of the study area. [ABSTRACT FROM AUTHOR]

We investigated chloroquine sensitivity to Plasmodium falciparum in travelers returning to France and Canada from Haiti during a 23-year period. Two of 19 isolates obtained after the 2010 earthquake showed mixed pfcrt 76K+T genotype and high 50% inhibitory concentration. Physicians treating malaria acquired in Haiti should be aware of possible chloroquine resistance. [ABSTRACT FROM AUTHOR]

In Liberia, little information is available on the efficacy of antimalarials against Plasmodium falciparum malaria. We measured parasitological resistance to chloroquine and sulfadoxine-pyrimethamine (SP) in Harper, south-west Liberia in a 28-d study in vivo. A total of 50 patients completed follow-up in the chloroquine group, and 66 in the SP group. The chloroquine failure rate was 74·0% (95% confidence interval [95% CI] 59·7–85·4%) after 14 d of follow-up and 84·0% (95% CI 70·9–92·8%) after 28 d (no polymerase chain reaction [PCR] analysis was performed to detect reinfections in this group). In the SP group, the failure rate was 48·5% (95% CI 36·2–61·0%) after 14 d and 69·7% (95% CI 57·1–80·4%) after 28 d, readjusted to 51·5% (95% CI 38·9–64·0%) after taking into account reinfections detected by PCR. Genomic analysis of parasite isolates was also performed to look for point mutations associated with resistance. Genotyping of parasite isolates revealed that all carried chloroquine-resistant K-76T mutations at gene pfcrt, whereas the triple mutation (S108N, N511, C59R) at dhfr and the A437G mutation at dhps, both associated with resistance to SP, were present in 84% and 79% of pretreatment isolates respectively. These results seriously question the continued use of chloroquine and SP in Harper and highlight the urgency of making alternative antimalarial therapies available. Our study confirms that resistance to chloroquine may be high in Liberia and yields hitherto missing information on SP. [Copyright &y& Elsevier]

The present study was undertaken to explore the antimalarial effect of a series of dicatecholate iron chelators. They may be made more or less lipophilic by increasing or reducing the length of the R substituent on the nitrogen. In vitro activity against the W2 and 3D7 clones of Plasmodium falciparum, toxicity on Vero cells and toxicity on uninfected erythrocytes by measure of the released haemoglobin were assessed for each compound. These findings were compared with the ability of iron(III), iron(II) and ferritin to reverse the inhibitory effect of catecholates. This study shows that increased lipid solubility of catecholate iron chelators does not lead to improved antimalarial activity. However, their activity is well correlated with their interaction with iron and with their toxicity against Vero cells. This study demonstrates a potent antimalarial effect of FR160 (R = C9H19) on five different strains of P. falciparum in vitro. FR160 inhibited parasite growth with an IC50 between 0.8 and 1.5 micro M. The effects of FR160 on mammalian cells were minimal compared with those obtained with malaria parasites. FR160 acted on parasites at considerably higher rates than desferrioxamine, and at all stages of parasite growth. The drug was more effective at the late trophozoite and young schizont stages, although FR160 affected rings and schizonts as well. Ascorbic acid, a free radical scavenger, reduced the activities of FR160 and artesunate. FR160 might induce formation of free radicals, which could explain why FR160 antagonized the effects of artesunate and dihydroartemisinin. [ABSTRACT FROM AUTHOR]

High levels of antimalarial drugs have been shown to be inhibitory to the oxidative metabolism of human neutrophils in vitro. In this study, chemiluminescence of, and chloroquine concentrations in, neutrophils from volunteers treated with prophylactic or therapeutic malaria regimens were assessed. Although detectable chloroquine levels were found in neutrophils, their chemiluminescence was not reduced at prophylactic or at therapeutic drug levels, in comparison with controls without chloroquine treatment. At these clinically achievable concentrations, chloroquine was not found to interfere with the oxidative metabolism of neutrophils. [ABSTRACT FROM AUTHOR]