Evolutionary history of Leishmania killicki (synonymous Leishmania tropica) and taxonomic implications

Background: Leishmania (L.) killicki is responsible for the chronic cutaneous leishmaniasis. The taxonomic status of this parasite is still not well defined. It was suggested on one hand to include this taxon within L. tropica complex but also on the other hand to consider it as a distinct phylogenetic complex. The present work represents the more detailed study on the evolutionary history of L. killicki relative to L. tropica and the taxonomic implications. Methods: Thirty five L. killicki and 25 L. tropica strains isolated from humans and from several countries were characterized using the MultiLocus Enzyme Electrophoresis (MLEE) and the MultiLocus Sequence Typing (MLST) approaches. Results: The genetic and phylogenetic analyses strongly support that L. killicki belongs to L. tropica complex. The study suggests the emergence of L. killicki by a funder effect followed by an independent evolution from L. tropica, but does not validate the species status of this taxon. In this context, we suggest to call this taxon L. killicki (synonymous L. tropica) until further epidemiological and phylogenetic studies justify the L. killicki denomination. Conclusions: These findings provided taxonomic and phylogenetic informations on L. killicki and helped to better know the evolutionary history of this taxon

Réalisation d'un système d'émission-réception 4 canaux dédié au cerveau de rat pour un système RM à 7T

International audienceUn système ainsi qu'une bobine d'émission-réception ont été réalisés pour un système RM à 7 T. Ce système d'émission-réception 4 canaux permet de créer un champ magnétique RF B1+ polarisé circulairement. La combinaison constructive des phases des 4 canaux a été démontrée par des images RM

Feasibility of self-collection of fecal specimens by randomly sampled women for health-related studies of the gut microbiome

BACKGROUND: The field of microbiome research is growing rapidly. We developed a method for self-collection of fecal specimens that can be used in population-based studies of the gut microbiome. We conducted a pilot study to test the feasibility of our methods among a random sample of healthy, postmenopausal women who are members of Kaiser Permanente Colorado (KPCO). We aimed to collect questionnaire data, fecal and urine specimens from 60 women, aged 55–69, who recently had a normal screening mammogram. We designed the study such that all questionnaire data and specimens could be collected at home. RESULTS: We mailed an invitation packet, consent form and opt-out postcard to 300 women, then recruited by telephone women who did not opt-out. Verbally consented women were mailed an enrollment package including a risk factor questionnaire, link to an online diet questionnaire, specimen collection kit, and instructions for collecting stool and urine. Specimens were shipped overnight to the biorepository. Of the 300 women mailed an invitation packet, 58 (19%) returned the opt-out postcard. Up to 3 attempts were made to telephone the remaining women, of whom 130 (43%) could not be contacted, 23 (8%) refused, and 12 (4%) were ineligible. Enrollment packages were mailed to 77 women, of whom 59 returned the risk factor questionnaire and specimens. We found no statistically significant differences between enrolled women and those who refused participation or could not be contacted. CONCLUSIONS: We demonstrated that a representative sample of women can be successfully recruited for a gut microbiome study; however, significant personal contact and carefully timed follow-up from the study personnel are required. The methods employed by our study could successfully be applied to analytic studies of a wide range of clinical conditions that have been postulated to be influenced by the gut microbial population

Construction of a flood forecasting model on the river Odet (Finistere, France) with MASCARET

Water Qualit

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO

Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file

Evaluation of two candidate molecules - TCTP and cecropin - on the establishment of Trypanosoma brucei gambiense into the gut of Glossina palpalis gambiensis

Trypanosomiasis, transmitted by tsetse flies (Glossina spp.), poses a significant health threat in 36 sub-Saharan African countries. Current control methods targeting tsetse flies, while effective, allow reinfestation. This study investigates paratransgenesis, a novel strategy to engineer symbiotic bacteria in tsetse flies, Sodalis glossinidius, to deliver anti-trypanosome compounds. Disrupting the trypanosome life cycle within the fly and reducing parasite transmission could offer a sustainable solution for trypanosomiasis control. In this context, we tested the effect of cecropin, reported to be lethal for Trypanosoma cruzi (Chagas disease) and TbgTCTP (Translationally Controlled Tumor Protein from Trypanosoma brucei gambiense), previously reported to modulate the growth of bacteria isolated from the fly microbiome, to delay the first peak of parasitemia and the death of trypanosome-infected mice. We have successfully cloned and transfected the genes encoding the two proteins into Sodalis strains. These Sodalis recombinant strains (recSodalisTbgTCTP and recSodaliscecropin) have been then microinjected into the L3 larval stage of Glossina palpalis gambiensis flies. The stability of the cloned genes was checked up to the 20th day after microinjection of recSodalis. The rate of fly emergence from untreated pupae was 95%; it was reduced by nearly 50% due to the mechanical injury caused by microinjection. It decreased to nearly 7% when larvae were injected with recSodalisTbgTCTP, which suggests TCTP could have a lethal impact to larvae development. When challenged with T. brucei gambiense, a slightly lower, but statistically non-significant, infection rate was recorded in flies harboring recSodaliscecropin compared to control flies. The effect of recSodalisTbgTCTP could not be measured due to the very low rate of fly emergence after corresponding treatment of the larvae. The results do not allow to conclude on the effect of cecropin or TCTP, delivered by para-transgenesis into the fly's gut, on the fly infection by the trypanosome. Nevertheless, the results are encouraging insofar as the technical approach works on the couple G. p. gambiensis/T. brucei gambiense. The next step will be to optimize the system and test other targets chosen among the ESPs (Excreted-Secreted Proteins) of the trypanosome secretum, or the differentially expressed genes associated with the sensitivity/resistance of the fly to trypanosome infection