Un nouveau variant enzymatique de<i>Leishmania Infantum</i>Nicolle, 1908,

Belazzoug, S; Lanotte, G.; Maazoun, R.; Pratlong, Francine; Rioux, J. A.

doi:10.1051/parasite/19856011

Cited by 43 publications

(10 citation statements)

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“…2. The small numbers correspond to the species and isolates listed in Table 1. well as isoenzymes (46,50) (2,7,9,11). Our data indicate that nuclear DNA probes may also be employed in the identification of species, as the DNA fragment patterns among the species complexes are largely or completely different (Fig.…”

Section: Discussionmentioning

confidence: 99%

Evolution of the genus Leishmania as revealed by comparisons of nuclear DNA restriction fragment patterns.

Beverley¹,

Ismach²,

Pratt³

1987

Proc. Natl. Acad. Sci. U.S.A.

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Restriction endonuclease DNA fragment patterns have been used to examine the relationships among 28 isolates of Leishmania as well as Crithidia, Endotrypanum, and Trypanosoma cruzi. Fragments of nuclear DNA were generated with six restriction enzymes, and blots were hybridized with probes from three loci. Among the major lineages the fragment patterns are essentially completely different, while within the major lineages various degrees of divergence are found. Molecular evolutionary trees were constructed using the method of Nei and Li to estimate the percent nucleotide sequence divergence among strains from the fraction of fragments shared.Defined groups, such as species or subspecies within the major lineages, are also grouped by nuclear DNA comparisons. Within the donovani complex, we find Leishmania donovani chagasi and Leishmania donovani infantum to be as similar as strains within Leishmania donovani donovani, consistent with the proposal by other workers that New World visceral leishmaniasis originated quite recently.Protozoans belonging to the genus Leishmania are frequently parasites in humans, causing a spectrum of diseases whose severity ranges from mild through severely disfiguring to lethal (1). A variety of clinical, biological, and geographical criteria were initially used to classify species (1). With further study it became evident that geographical and pathological criteria were often inadequate to discriminate among different isolates, and biochemical and molecular approaches were employed, including comparisons of isoenzymes (2-5), kinetoplast DNA (6-9), proteins (10), and antigens (11)(12)(13)(14) Comparisons of nuclear DNA have been successfully employed in other organisms for the estimation of temporal and cladistic relationships of species (18)(19)(20). We used Southern blot hybridization with various defined nuclear DNA probes to obtain data that was analyzed by the method of Nei and Li (21) to estimate first the fraction of DNA fragments shared among species and then the percent of nucleotide sequence divergence. This method yields results that generally agree with comparisons of DNA sequences or of other parameters (refs. 20,22,and 23; personal communication). However, the calculation of percent divergence assumes that all fragment differences are attributable to point mutations. This assumption may not always be valid for nuclear DNA, where the presence of detectable length mutations would lower the fraction of fragments shared between two species and thus inflate the estimate of sequence divergence (24). To detect any anomalies caused by length mutations, we examined three independent regions of the nuclear genome and analyzed each data set separately as well as in combination. Our analysis indicates that the fragment comparison method is indeed suitable for comparisons within the major lineages of Leishmania.

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Section: Discussionmentioning

confidence: 99%

Evolution of the genus Leishmania as revealed by comparisons of nuclear DNA restriction fragment patterns.

Beverley¹,

Ismach²,

Pratt³

1987

Proc. Natl. Acad. Sci. U.S.A.

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“…Zymodeme MON-1 is the main agent of HVL. Zymodeme MON-24 was isolated from both SCL and HVL cases (Belazzoug et al 1985b;Benikhlef et al 2001). Zymodemes MON-34 and MON-80 were isolated from SCL immunocompetent patients.…”

Section: Introductionmentioning

confidence: 99%

First detection of Leishmania infantum DNA in Phlebotomus longicuspis Nitzulescu, 1930 from visceral leishmaniasis endemic focus in Algeria

et al. 2012

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Two clinico-epidemiological forms of leishmaniasis caused by Leishmania infantum complex are endemic in Algeria: human visceral leishmaniasis (HVL) and sporadic cutaneous leishmaniasis. In the northern part of the country, the Kabylian region is the main endemic HVL focus with more than 200 cases recorded annually. During the summer of 2009, an entomological study was performed in Larbaa Nath Irathen with the aim to identify the vectors of Leishmania and of phleboviruses. In the present paper, we report the results of the Leishmania vectors. In the field, female sand flies, which were alive at collection time, were morphologically identified and examined for the presence of promastigotes. The remaining sandflies (males and dead females) were carried to the laboratory for morphological identification and molecular analysis. Total DNA was extracted from each female sandfly, and ITS2 Leishmania was amplified by PCR. A total of 883 sandfly specimens were collected. Ten distinct species were morphologically identified: one species belonged to the Sergentomyia genus and nine to the Phlebotomus genus. L. infantum DNA was amplified in 1/169 (0.6%) dissected dead females, one Phlebotomus longicuspis. Our data support the Parrot's hypothesis raised in 1941 concerning the role of P. longicuspis in the transmission of L. infantum.

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“…Elle est causée par trois parasites différents, Leishmania major MON-25, inféodé aux régions steppiques et sahariennes, Leishmania infantum MON-24 dans la région du Tell [3,5,15,16] et L. killicki, limité pour le moment à Ghardaia dans le Sud algérien [17]. Longtemps confinée au Sahara, la LCZ à L. major connaît une extension géographique en dehors des foyers naturels de la maladie.…”

Section: Introductionunclassified

Extension de Leishmania major au nord de l’Algérie

Boudrissa

Cherif

Kherrachi

et al. 2011

Bull. Soc. Pathol. Exot.

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Since a long time, Leishmania major and L. infantum foci in Algeria were geographically separated by the mountains of the Tell Atlas which represent a natural barrier. Recently, a new focus of cutaneous leishmaniasis (CL) has emerged in the village of El M'hir, located on the north side of the chain of the Tell Atlas, in the basin of the Soummam. During the period 2004-2010, 152 CL cases have been registered and 12 isolates were obtained from patients who declared never having been outside the village the last years. The identification of the parasites showed that all strains belonged to L major MON-25. Investigations on the reservoir hosts showed the presence of the sand rat (Psammomys obesus), for the first time, in this locality. Five strains isolated from this rodent belonged to L. major MON-25. The sand rat, which is usually observed around the chotts in the Saharan and steppe areas, acts as the main reservoir of L. major in Algeria. Its presence in the new focus of El M'hir is reported for the first time. Entomological surveys carried out in 2009 showed the predominance of two sandfly species: Phlebotomus papatasi and P. perniciosus. The first one is known as a vector of L major in the Algerian Sahara. This study highlights the spread of L. major from the arid zones towards the semi arid areas, particularly in the Soummam valley. Climate changes and desertification observed in the steppe area northern Sahara could play a role in the extension of the disease.

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Un nouveau variant enzymatique deLeishmania InfantumNicolle, 1908,

Cited by 43 publications

References 1 publication

Evolution of the genus Leishmania as revealed by comparisons of nuclear DNA restriction fragment patterns.

Evolution of the genus Leishmania as revealed by comparisons of nuclear DNA restriction fragment patterns.

First detection of Leishmania infantum DNA in Phlebotomus longicuspis Nitzulescu, 1930 from visceral leishmaniasis endemic focus in Algeria

Extension de Leishmania major au nord de l’Algérie

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