First Detection of Leishmania major DNA in Sergentomyia (Spelaeomyia) darlingi from Cutaneous Leishmaniasis Foci in Mali

Leishmania major complex is the main causative agent of zoonotic cutaneous leishmaniasis (ZCL) in the Old World. Phlebotomus papatasi and Phlebotomus duboscqi are recognized vectors of L. major complex in Northern and Southern Sahara, respectively. In Mali, ZCL due to L. major is an emerging public health problem, with several cases reported from different parts of the country. The main objective of the present study was to identify the vectors of Leishmania major in the Bandiagara area, in Mali. Methodology/Principal Findings: An entomological survey was carried out in the ZCL foci of Bandiagara area. Sandflies were collected using CDC miniature light traps and sticky papers. In the field, live female Phlebotomine sandflies were identified and examined for the presence of promastigotes. The remaining sandflies were identified morphologically and tested for Leishmania by PCR in the ITS2 gene. The source of blood meal of the engorged females was determined using the cyt-b sequence. Out of the 3,259 collected sandflies, 1,324 were identified morphologically, and consisted of 20 species, of which four belonged to the genus Phlebotomus and 16 to the genus Sergentomyia. Leishmania major DNA was detected by PCR in 7 of the 446 females (1.6%), specifically 2 out of 115 Phlebotomus duboscqi specimens, and 5 from 198 Sergentomyia darlingi specimens. Human DNA was detected in one blood-fed female S. darlingi positive for L. major DNA. Conclusion: Our data suggest the possible involvement of P. duboscqi and potentially S. darlingi in the transmission of ZCL in Mali

Seasonality and Prevalence of Leishmania major Infection in Phlebotomus duboscqi Neveu-Lemaire from Two Neighboring Villages in Central Mali

Phlebotomus duboscqi is the principle vector of Leishmania major, the causative agent of cutaneous leishmaniasis (CL), in West Africa and is the suspected vector in Mali. Although found throughout the country the seasonality and infection prevalence of P. duboscqi has not been established in Mali. We conducted a three year study in two neighboring villages, Kemena and Sougoula, in Central Mali, an area with a leishmanin skin test positivity of up to 45%. During the first year, we evaluated the overall diversity of sand flies. Of 18,595 flies collected, 12,952 (69%) belonged to 12 species of Sergentomyia and 5,643 (31%) to two species of the genus Phlebotomus, P. duboscqi and P. rodhaini. Of those, P. duboscqi was the most abundant, representing 99% of the collected Phlebotomus species. P. duboscqi was the primary sand fly collected inside dwellings, mostly by resting site collection. The seasonality and infection prevalence of P. duboscqi was monitored over two consecutive years. P. dubsocqi were collected throughout the year. Using a quasi-Poisson model we observed a significant annual (year 1 to year 2), seasonal (monthly) and village effect (Kemena versus Sougoula) on the number of collected P. duboscqi. The significant seasonal effect of the quasi-Poisson model reflects two seasonal collection peaks in May-July and October-November. The infection status of pooled P. duboscqi females was determined by PCR. The infection prevalence of pooled females, estimated using the maximum likelihood estimate of prevalence, was 2.7% in Kemena and Sougoula. Based on the PCR product size, L. major was identified as the only species found in flies from the two villages. This was confirmed by sequence alignment of a subset of PCR products from infected flies to known Leishmania species, incriminating P. duboscqi as the vector of CL in Mali

Glucagon-like peptide-1-(7-36) amide, oxyntomodulin, and glucagon interact with a common receptor in a somatostatin-secreting cell line.

Glucagon-like peptide-1(7-36)amide (tGLP-1), oxyntomodulin (OXM), and glucagon are posttranslational end products of the glucagon gene expressed in intestinal L-cells. In vivo, these peptides are potent inhibitors of gastric acid secretion via several pathways, including stimulation of somatostatin release. We have examined the receptors through which these peptides stimulate somatostatin secretion using the somatostatin-secreting cell line RIN T3. tGLP-1, OXM, and glucagon stimulated somatostatin release and cAMP accumulation in RIN T3 cells to similar maximum levels, with ED50 values close to 0.2, 2, and 50 nM and 0.02, 0.3, and 8 nM, respectively. Binding of [125I]tGLP-1, [125I]OXM, and [125I]glucagon to RIN T3 plasma membranes was inhibited by the three peptides, with relative potencies as follows: tGLP-1 > OXM > glucagon. Whatever the tracer used, the IC50 for tGLP-1 was close to 0.15 nM and was shifted rightward for OXM and glucagon by about 1 and 2-3 orders of magnitude, respectively. Scatchard analyses for the three peptides were compatible with a single class of receptor sites displaying a similar maximal binding close to 2 pmol/mg protein. In the hamster lung fibroblast cell line CCL39 transfected with the receptor for tGLP-1, binding of [125I]tGLP-1 was inhibited by tGLP-1, OXM, and glucagon, with relative potencies close to those obtained with RIN T3 membranes. Chemical cross-linking of [125I]tGLP-1, [125I]OXM, and [125I]glucagon revealed a single band at 63,000 mol wt, the intensity of which was dose-dependently reduced by all three peptides. These data suggest that in the somatostatin-secreting cell line RIN T3, OXM and glucagon stimulate somatostatin release through a tGLP-1-preferring receptor. This suggests that some biological effects, previously described for these peptides, might be due to their interaction with this receptor

Comparative effects of GLP-1-(7-36) amide, oxyntomodulin and glucagon on rabbit gastric parietal cell function.

We have investigated in vitro, the effects of glucagon-like peptide-1-(7-36) amide (GLP-1-(7-36) amide), oxyntomodulin and glucagon on two rabbit parietal cell-enriched fractions (F3, F3n), with parietal cell contents of 60% and 88%, respectively. Histamine (10(-5) M) stimulated [14C]aminopyrine accumulation to an amount of 850% in excess of the basal level, whereas GLP-1-(7-36) amide (10(-7) M) and oxyntomodulin (10(-6) M) induced increases of 50% and 30%, respectively. With a histamine concentration of 10(-6) M, [14C]aminopyrine accumulation was stimulated to 498% in excess of the basal level; GLP-1-(7-36) amide (10(-7) M) and oxyntomodulin (10(-7) M) induced increases of 18% and 15%, respectively. With these parameters, oxyntomodulin[19-37] and glucagon were without effect. Specific binding of [125I]GLP-1-(7-36) amide to parietal cell plasma membranes was inhibited dose-dependently by GLP-1-(7-36) amide, oxyntomodulin and glucagon with inhibitory concentrations of 0.25 nM, 65 nM and 800 nM, respectively. No specific binding of [125I]oxyntomodulin or [125I]glucagon was detectable. GLP-1-(7-36) amide receptor mRNA was only detected in parietal cell-enriched fractions. GLP-1-(7-36) amide, oxyntomodulin and glucagon stimulated parietal cell cAMP production to similar maximal levels with median values close to 0.28 nM, 10.5 nM and 331.7 nM, whereas oxyntomodulin[19-37] had no effect. The maximal cAMP production induced by GLP-1-(7-36) amide, oxyntomodulin or glucagon was additive to that induced by histamine.(ABSTRACT TRUNCATED AT 250 WORDS

Version francaise des recommandations de la declaration d'Ottawa sur la conception et la conduite ethique d'essais randomises en clusters, dans le contexte legislatif francais.

International audienceINTRODUCTION: There is growing evidence on the ethical challenges raised by cluster randomized trials. This specificity is not reflected in the legal texts regulating research, which creates difficulties for researchers implementing these experimental designs. The Ottawa Statement (Weijer et al. 2012) aims to provide detailed guidance on the ethical design, conduct and assessment of cluster trials. More broadly aims to help research stakeholders and decision-makers to make informed ethical decisions regarding the particularity of these experimental designs. It seems that this international statement, written in English, is not sufficiently accessible to all of the French professionals involved in health research. The aim of this article is to provide these professionals with a contextualized and illustrated French translation of the "Ottawa statement". METHOD: . The "complex design" working group of the RECaP network (Research in Clinical Epidemiology and Public Health), carried out this work. A first version was discussed by the authors in several meetings. It was completed by contextual explanations and examples of French studies currently conducted by the authors. The final version was obtained by consensus and validated by the group. RESULTS: . This work reports 15 recommendations grouped into 7 key questions: How to justify cluster design? How to submit an article to an ethics committee? How to identify research participants? How and when to obtain informed consent? Who are the gatekeepers? How to assess benefits and harm? How to protect vulnerable participants? Each of these recommendations is specific to cluster trials. The recommendations are explained and detailed through concrete examples. CONCLUSION: Without interfering with current French laws, this work provides a framework for the organization, conduct and ethical assessment of cluster randomized trials in France. In the present-day context, it is essential that all concerned groups can base their decisions on recommendations in line with the elementary principles of health research ethics.INTRODUCTION : Il existe une littérature croissante sur les défis éthiques soulevés par les essais randomisés en clusters (ou en grappes). Cette spécificité n'est pas prise en compte dans les textes réglementaires qui régissent la recherche, ce qui est source de difficultés pour les chercheurs utilisant ces schémas expérimentaux. La Déclaration d'Ottawa (Weijer et al. 2012) vise à fournir des conseils détaillés sur l’éthique de la conception, de la conduite et de l’évaluation des essais en clusters. Elle a pour objectif d'aider l'ensemble des acteurs de la recherche (parties prenantes et décideurs) à prendre des décisions éclairées en termes d’éthique relative à la particularité de ces schémas expérimentaux. Il semble que cette déclaration internationale ne soit pas assez accessible auprès de l'ensemble des acteurs français de la recherche en santé. L'objectif de cet article est de proposer à ces professionnels une traduction française de l’« Ottawa Statement », contextualisée et illustrée. METHODE : Le groupe de travail « Design complexe » du réseau RECaP (Recherche en épidémiologie clinique et en santé publique) a réalisé ce travail. Une première version a été discutée par les auteurs au travers de plusieurs réunions. Elle a été complétée par des explications contextuelles et par des exemples d’études françaises actuellement menées par les auteurs. La dernière version a été obtenue par consensus et validée par le groupe. RESULTATS : Ce travail présente les 15 recommandations regroupées en sept grandes questions : quelle justification pour le design en clusters ? Comment soumettre à un comité d’éthique ? Comment identifier les participants à la recherche ? Quand et comment obtenir un consentement éclairé ? Qui sont les personnes référentes ? Comment évaluer les bénéfices et les risques ? Comment protéger les personnes vulnérables ? Chacune de ces recommandations porte spécifiquement sur les essais en clusters. Ces recommandations sont expliquées et détaillées au travers d'exemples. CONCLUSION : Ce travail permet de fournir un cadre pour la mise en place, la conduite et l’évaluation éthique des essais randomisés en clusters en France. Sans ingérence dans les lois actuelles françaises. Dans le contexte actuel, il est indispensable que l'ensemble des groupes concernés puissent appuyer leurs décisions sur des recommandations en accord avec les principes élémentaires de l’éthique de la recherche en santé