34 research outputs found
Analysis of Tunisian date palm germplasm using simple sequence repeat primers
Inter Simple Sequence Repeat (ISSR) markers involve polymerase chain reaction (PCR) amplification of DNA using a single primer composed of a microsatellite sequence. ISSR technology rapidly reveals high polymorphic fingerprints and determines genetic diversity. We used genetic markers generated from selected ISSR primers to assess genetic diversity among a set of Tunisian date palm varieties. Seven primers were used to cluster 12 date palm varieties and 77 polymorphic markers were sufficient to identify all of the varieties. These discrete molecular markers were used to estimate genetic distances among the 12 accessions and to examine their genetic relationships. Data analysis identified phenetic groups that were in agreement with those obtained according to agronomic traits and random amplified polymorphic DNA (RAPD) markers. Among the 12 simple sequence repeat (SSR) motifs tested, the most abundant were AG.
Key Words: Genetic diversity; ISSR polymorphisms; date palm; Pheonix dactylifera.
African Journal of Biotechnology Vol. 3 (4), 2004: 215-21
Vivax malaria in Mauritania includes infection of a Duffy-negative individual
<p>Abstract</p> <p>Background</p> <p>Duffy blood group polymorphisms are important in areas where <it>Plasmodium vivax </it>is present because this surface antigen is thought to act as a key receptor for this parasite. In the present study, Duffy blood group genotyping was performed in febrile uninfected and <it>P. vivax</it>-infected patients living in the city of Nouakchott, Mauritania.</p> <p>Methods</p> <p><it>Plasmodium vivax </it>was identified by real-time PCR. The Duffy blood group genotypes were determined by standard PCR followed by sequencing of the promoter region and exon 2 of the Duffy gene in 277 febrile individuals. Fisher's exact test was performed in order to assess the significance of variables.</p> <p>Results</p> <p>In the Moorish population, a high frequency of the <it>FYB<sup>ES</sup>/FYB<sup>ES </sup></it>genotype was observed in uninfected individuals (27.8%), whereas no <it>P. vivax</it>-infected patient had this genotype. This was followed by a high level of <it>FYA/FYB</it>, <it>FYB/FYB</it>, <it>FYB/FYB<sup>ES </sup></it>and <it>FYA/FYB<sup>ES </sup></it>genotype frequencies, both in the <it>P. vivax</it>-infected and uninfected patients. In other ethnic groups (Poular, Soninke, Wolof), only the <it>FYB<sup>ES</sup>/FYB<sup>ES </sup></it>genotype was found in uninfected patients, whereas the <it>FYA/FYB<sup>ES </sup></it>genotype was observed in two <it>P. vivax</it>-infected patients. In addition, one patient belonging to the Wolof ethnic group presented the <it>FYB<sup>ES</sup>/FYB<sup>ES </sup></it>genotype and was infected by <it>P. vivax</it>.</p> <p>Conclusions</p> <p>This study presents the Duffy blood group polymorphisms in Nouakchott City and demonstrates that in Mauritania, <it>P. vivax </it>is able to infect Duffy-negative patients. Further studies are necessary to identify the process that enables this Duffy-independent <it>P. vivax </it>invasion of human red blood cells.</p
Studies on Arabic Dialectology and Sociolinguistics
This volume contains over fifty articles related to various fields of modern Arabic dialectology. All the articles are revised and enhanced versions of papers read on the 12th Conference of the Association Internationale de Dialectologie Arabe (AIDA) held in Marseille in June 2017. Since its first conference in Paris in 1993, AIDA members gather every two years in different country. The collection of the AIDA proceedings offer an updated insight of the development of the field. During the past few decadesthe the study of Arabic dialects has become an important branch of research covering a wide range of subjects from phonological analyses, morphosyntax, semantics to pragmatics, sociolinguistics, folk linguistics, studies on literacy and writings, cultural and artistic practices, etc. As many articles of this volume illustrate, the study of Arabic dialects explores different aspects of the languages and cultures of the contemporary Arab world. A remarkable feature is the growing and constant participation of young scholars from all around the globe
Malaria in Mauritania : retrospective and prospective overview
Malaria has become a major public health problem in Mauritania since the 1990s, with an average of 181,000 cases per year and 2,233,066 persons at risk during 1995-2012. This paper provides the first publicly available overview of malaria incidence and distribution in Mauritania. Information on the burden and malaria species distribution is critical for guiding national efforts in malaria control. As the incidence of malaria changes over time, regular updates of epidemiological data are necessary
Aedes aegypti (Diptera : Culicidae) in Mauritania : first report on the presence of the arbovirus mosquito vector in Nouakchott
Aedes aegypti L. (Diptera: Culicidae) is a major vector of yellow fever, dengue, and chikungunya viruses throughout tropical and subtropical areas of the world. Although the southernmost part of Mauritania along the Senegal river has long been recognized at risk of yellow fever transmission, Aedes spp. mosquitoes had never been reported northwards in Mauritania. Here, we report the first observation of Aedes aegypti aegypti (L.) and Aedes (Ochlerotatus) caspius (Pallas, 1771) in the capital city, Nouakchott. We describe the development sites in which larvae of the two species were found, drawing attention to the risk for emergence of arbovirus transmission in the city
Knowledge, attitudes and practices regarding malaria among the residents of Nouakchott, Mauritania
Malaria-associated morbidity during the rainy season in Saharan and Sahelian zones in Mauritania
Reliable epidemiological data based on laboratory-confirmed cases are scarce in Mauritania. A large majority of reported malaria cases are based on presumptive clinical diagnosis. The present study was conducted to establish a reliable database on malaria morbidity among febrile paediatric and adult patients consulting spontaneously at public health facilities in Nouakchott, situated in the Saharan zone, and in Hodh Elgharbi region in the Sahelian zone in south-east Mauritania during the peak transmission periods. Giemsa-stained thin and thick films were examined under the microscope, and the parasite density was determined according to the procedures recommended by the World Health Organization. Microscopy results were confirmed by rapid diagnostic test for malaria. A total of 1161 febrile patients (498 in Nouakchott and 663 in Hodh Elgharbi region) were enrolled during two successive peak transmission periods in 2009 and 2010. In Nouakchott, 253 (50.8%) febrile patients had positive smears (83% Plasmodium vivax monoinfections and 17% Plasmodium falciparum monoinfections). In Hodh Elgharbi, 378 of 663 patients (57.0%) were smear-positive, mostly due to P. falciparum monoinfections (96.6%). Unlike in Nouakchott, mixed P. falciparum-P. vivax infections, as well as P. vivax, P. ovale, and P. malariae monoinfections, were also observed at a very low prevalence in southern Mauritania. In Nouakchott, malaria occurred more frequently (P 5 years old and adults than in young children aged 0.05) in relation with age groups. The present study confirmed the predominance of P. falciparum in southern Mauritania reported in previous studies. The presence of P. vivax in Nouakchott is a new epidemiological reality that requires an urgent adoption of novel strategies for parasitological and vector control to combat urban malaria. Moreover, the present study provides evidence-based data on malaria burden in two regions in Mauritania that may serve as a springboard to establish and develop a national surveillance system of malaria epidemiology