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1.
Parasite ; 30: 18, 2023.
Article in English | MEDLINE | ID: mdl-37222517

ABSTRACT

New World sandflies are vectors of leishmaniasis, bartonellosis, and some arboviruses. A classification based on 88 morphological characters was proposed 27 years ago when the New World phlebotomines were organized into two tribes Hertigiini and Phlebotomini. The latter was structured into four subtribes (Brumptomyiina, Sergentomyiina, Lutzomyiina, and Psychodopygina) and 20 genera. The subtribe Psychodopygina, including most of the American vectors of tegumentary Leishmania comprises seven genera from which no molecular work has been produced to support this classification. Here, we carried out a molecular phylogeny based on combined sequences (1,334 bp) of two genes: partial 28S rDNA and mtDNA cytochrome b from 47 taxa belonging to the Psychodopygina. The Bayesian phylogenetic reconstruction agreed with the classification based on morphological characters, supporting the monophyly of the genera Psychodopygus and Psathyromyia, whereas Nyssomyia and Trichophoromyia seemed to be paraphyletic. The paraphylies of the two latter groups were exclusively caused by the doubtful position of the species Ny. richardwardi. Our molecular analysis provides additional support to adopt the morphologic classification of Psychodopygina.


Title: La phylogénie moléculaire des Psychodopygina (Diptera, Psychodidae) soutient la systématique morphologique de ce groupe de vecteurs de leishmaniose cutanée du Nouveau Monde. Abstract: Les phlébotomes du nouveau monde sont des vecteurs de leishmaniose, de bartonellose et de certains arbovirus. Une classification basée sur 88 caractères morphologiques a été proposée il y a 27 ans lorsque les phlébotomes du nouveau monde ont été organisés en deux tribus Hertigiini et Phlebotomini. Cette dernière était structurée en quatre sous-tribus (Brumptomyiina, Sergentomyiina, Lutzomyiina et Psychodopygina) et 20 genres. La sous-tribu des Psychodopygina, qui inclut la plupart des vecteurs américains de la leishmaniose cutanée, comprend sept genres mais aucun travail moléculaire n'a été produit pour soutenir cette classification. Dans cet article, nous avons réalisé une phylogénie moléculaire basée sur des séquences combinées (1334 pb) de deux gènes : ADNr 28S partiel et cytochrome b (ADNmt) chez 47 taxons appartenant aux Psychodopygina. La reconstruction phylogénique bayésienne est en accord avec la classification basée sur les caractères morphologiques, soutenant la monophylie des genres Psychodopygus et Psathyromyia, alors que Nyssomyia et Trichophoromyia semblent être paraphylétiques. Les paraphylies des deux derniers groupes sont exclusivement causées par la position douteuse de la seule espèce Ny. richardwardi. Notre analyse moléculaire fournit une raison supplémentaire pour adopter la classification morphologique des Psychodopygina.


Subject(s)
Leishmania , Leishmaniasis, Cutaneous , Psychodidae , Animals , Phylogeny , Bayes Theorem , Leishmania/genetics
2.
Mol Ecol ; 32(8): 1817-1831, 2023 04.
Article in English | MEDLINE | ID: mdl-35000240

ABSTRACT

Changes in biodiversity may impact infectious disease transmission through multiple mechanisms. We explored the impact of biodiversity changes on the transmission of Amazonian leishmaniases, a group of wild zoonoses transmitted by phlebotomine sand flies (Psychodidae), which represent an important health burden in a region where biodiversity is both rich and threatened. Using molecular analyses of sand fly pools and blood-fed dipterans, we characterized the disease system in forest sites in French Guiana undergoing different levels of human-induced disturbance. We show that the prevalence of Leishmania parasites in sand flies correlates positively with the relative abundance of mammal species known as Leishmania reservoirs. In addition, Leishmania reservoirs tend to dominate in less diverse mammal communities, in accordance with the dilution effect hypothesis. This results in a negative relationship between Leishmania prevalence and mammal diversity. On the other hand, higher mammal diversity is associated with higher sand fly density, possibly because more diverse mammal communities harbor higher biomass and more abundant feeding resources for sand flies, although more research is needed to identify the factors that shape sand fly communities. As a consequence of these antagonistic effects, decreased mammal diversity comes with an increase of parasite prevalence in sand flies, but has no detectable impact on the density of infected sand flies. These results represent additional evidence that biodiversity changes may simultaneously dilute and amplify vector-borne disease transmission through different mechanisms that need to be better understood before drawing generalities on the biodiversity-disease relationship.


Subject(s)
Leishmania , Leishmaniasis , Psychodidae , Animals , Humans , Leishmania/genetics , Biodiversity , Zoonoses , Mammals
3.
PLoS Negl Trop Dis ; 15(12): e0009990, 2021 12.
Article in English | MEDLINE | ID: mdl-34890393

ABSTRACT

BACKGROUND: Discovered by Nicolle and Comte in 1908 in Tunisia, Leishmania infantum is an intracellular protozoan responsible for zoonotic canine leishmaniosis (CanL) and zoonotic human visceral leishmaniasis (HVL). It is endemic in several regions of the world, including Tunisia, with dogs considered as the main domestic reservoir. The geographic expansion of canine leishmaniosis (CanL) has been linked to global environmental changes that have affected the density and the distribution of its sand fly vectors. METHODOLOGY/PRINCIPAL FINDINGS: In this study, a cross-sectional epidemiological survey on CanL was carried out in 8 localities in 8 bioclimatic areas of Tunisia. Blood samples were taken from 317 dogs after clinical examination. Collected sera were tested by indirect fluorescent antibody test (IFAT; 1:80) for the presence of anti-Leishmania infantum antibodies. The overall seroprevalence was 58.3% (185/317). Among positive dogs, only 16.7% showed clinical signs suggestive of leishmaniosis. Seroprevalence rates varied from 6.8% to 84.6% and from 28% to 66% by bioclimatic zone and age group, respectively. Serological positivity was not statistically associated with gender. The presence of Leishmania DNA in blood, using PCR, revealed 21.2% (64/302) prevalence in dogs, which varied by bioclimatic zone (7.3% to 31%) and age group (7% to 25%). The entomological survey carried out in the studied localities showed 16 species of the two genera (Phlebotomus and Sergentomyia). P. perniciosus, P. papatasi, and P. perfiliewi were the most dominant species with relative abundances of 34.7%, 25% and 20.4%, respectively. CONCLUSIONS/SIGNIFICANCE: The present report suggests a significant increase of CanL in all bioclimatic areas in Tunisia and confirms the ongoing spread of the infection of dogs to the country's arid zone. Such an expansion of infection in dog population could be attributed to ecological, agronomic, social and climatic factors that affect the presence and density of the phlebotomine vectors.


Subject(s)
Antibodies, Protozoan/blood , Dog Diseases/epidemiology , Dog Diseases/immunology , Leishmania infantum/immunology , Leishmaniasis, Visceral/epidemiology , Leishmaniasis, Visceral/veterinary , Animals , Cross-Sectional Studies , Dog Diseases/parasitology , Dog Diseases/transmission , Dogs , Female , Insect Vectors/classification , Insect Vectors/parasitology , Leishmania infantum/genetics , Leishmania infantum/pathogenicity , Leishmaniasis, Visceral/immunology , Leishmaniasis, Visceral/transmission , Male , Phlebotomus/parasitology , Prevalence , Seroepidemiologic Studies , Tunisia/epidemiology
4.
Zootaxa ; 4747(2): zootaxa.4747.2.8, 2020 Mar 03.
Article in English | MEDLINE | ID: mdl-32230114

ABSTRACT

Examination of type specimens and topotypic material is often a necessary step to ascertain the validity of a species. Consequently, solid knowledge about type series, type locality and type depository is critical. In this paper, we provide a thorough review of the mosquito species originally described from specimens collected in French Guiana, with specific emphasis on the location of the current depositories of type material, the composition of type series and the delimitation of type localities. Information already published about the mosquito type material from French Guiana was gathered and efforts were made to ascertain the current location of their depositories. This investigation made it possible to locate a large part of the existing type material and to provide corrected information on type series and type localities, therefore providing a strong basis for future taxonomic research on mosquitoes. The type locality of Culex (Culex) pseudojanthinosoma Senevet Abonnenc is corrected from French Guiana to Africa, and this species is synonymized with Culex (Culex) duttoni Theobald.


Subject(s)
Culex , Culicidae , Animals , French Guiana
5.
Emerg Microbes Infect ; 8(1): 962-972, 2019.
Article in English | MEDLINE | ID: mdl-31259662

ABSTRACT

Europe is the world's leading tourism destination and is receiving every year travellers from areas with active arbovirus transmission. There is thus a threat of mosquito-borne virus emergence in Europe due to the presence of the invasive mosquito vector Aedes albopictus. Little attention has been paid about the possible role of indigenous mosquito species as vectors of emerging arboviruses. Here, we assessed the vector competence dynamic of Aedes geniculatus, a European anthropophilic mosquito species, for chikungunya virus (CHIKV) in comparison with an European population of Ae. albopictus. We revealed that Ae. geniculatus is highly susceptible to CHIKV infection and could transmit the virus. By specifically exploring the vector competence dynamic in both mosquito species, we revealed that the cumulative distribution of CHIKV incubation period in Ae. geniculatus was delayed by several days as compared to Ae. albopictus. Our results strengthen the importance of considering indigenous species as potential vectors for emerging arboviruses. They also revealed the importance of considering variation in arbovirus dissemination or transmission dynamics in mosquitoes when performing vector competence assays. We will discuss the implications of our results on a CHIKV outbreak dynamic in a theoretical framework.


Subject(s)
Aedes/virology , Chikungunya Fever/transmission , Chikungunya Fever/virology , Chikungunya virus/isolation & purification , Mosquito Vectors/virology , Aedes/physiology , Animals , Chikungunya virus/classification , Chikungunya virus/genetics , Europe , Female , Humans , Mosquito Vectors/physiology
6.
Parasite ; 26: 38, 2019.
Article in English | MEDLINE | ID: mdl-31259684

ABSTRACT

An inventory of Phlebotomine sandflies was carried out in the Ankarana tsingy located in far northern Madagascar. A total of 723 sandflies were used for morphological, morphometric, and molecular studies (sequencing of partial cytochrome B (mtDNA) and partial 28S (rDNA)). Nine species were identified: Phlebotomus fertei, Sergentomyia anka, Se. sclerosiphon, Se. goodmani, two species of the genus Grassomyia, as well as three new species described herein: Se. volfi n. sp., Se. kaltenbachi n. sp., and Se. ozbeli n. sp. The recognition of these new species is strongly supported by molecular analyses. The first two of the new species could not be classified into any existing subgenus, therefore we proposed two new subgenera (Ranavalonomyia subg. nov., and Riouxomyia subg. nov.), with combinations as: Sergentomyia (Ranavalonomyia) volfi and Sergentomyia (Riouxomyia) kaltenbachi. Our study reveals important molecular variability in Se. anka, with the recognition of a population whose taxonomic status remains below that of species. Our research confirms the need to further study the specific diversity of Malagasy sandflies, which until the start of this millennium remained mostly unknown.


TITLE: Les phlébotomes (Diptera, Psychodidae) des tsingy d'Ankarana dans le nord de Madagascar : inventaire et description de nouveaux taxons. ABSTRACT: Un inventaire des Phlébotomes a été réalisé dans les tsingy d'Ankarana à l'extrême nord de Madagascar. Au total, 723 phlébotomes ont servi à des études morphologique, morphométrique et moléculaire (séquençage d'une partie du cytochrome B (ADNmt) et d'une partie de l'ADNr 28S). Neuf espèces ont été identifiées : Phlebotomus fertei, Sergentomyia anka, Se. sclerosiphon, Se. goodmani, deux espèces du genre Grassomyia, ainsi que trois espèces nouvelles décrites dans ce travail : Se. volfi n. sp., Se. kaltenbachi n. sp., and Se. ozbeli n. sp. L'individualisation de chacune de ces espèces nouvelles est robustement soutenue par les analyses moléculaires. Les deux premières de ces espèces nouvelles ne pouvaient pas être classées dans un sous-genre existant et nous avons proposé pour elles deux sous-genres nouveaux : Ranavalonomyia subg. nov., et Riouxomyia subg. nov, avec les combinaisons Sergentomyia (Ranavalonomyia) volfi et Sergentomyia (Riouxomyia) kaltenbachi.Notre étude révèle une variabilité moléculaire marquée chez Se. anka avec l'individualisation d'une population dont le statut taxinomique demeure populationnel. Nos travaux confirment la nécessité de poursuivre l'étude de la biodiversité des Phlébotomes qui est restée méconnue dans ce pays jusqu'au début de ce millénaire.


Subject(s)
Phlebotomus/classification , Phylogeny , Animals , Cytochromes b/genetics , DNA, Mitochondrial/genetics , DNA, Ribosomal/genetics , Female , Genetic Variation , Insect Vectors/classification , Madagascar , Male , Species Specificity
7.
Mol Ecol Resour ; 17(2): 172-182, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27292284

ABSTRACT

Phlebotomine sand flies are haematophagous dipterans of primary medical importance. They represent the only proven vectors of leishmaniasis worldwide and are involved in the transmission of various other pathogens. Studying the ecology of sand flies is crucial to understand the epidemiology of leishmaniasis and further control this disease. A major limitation in this regard is that traditional morphological-based methods for sand fly species identifications are time-consuming and require taxonomic expertise. DNA metabarcoding holds great promise in overcoming this issue by allowing the identification of multiple species from a single bulk sample. Here, we assessed the reliability of a short insect metabarcode located in the mitochondrial 16S rRNA for the identification of Neotropical sand flies, and constructed a reference database for 40 species found in French Guiana. Then, we conducted a metabarcoding experiment on sand flies mixtures of known content and showed that the method allows an accurate identification of specimens in pools. Finally, we applied metabarcoding to field samples caught in a 1-ha forest plot in French Guiana. Besides providing reliable molecular data for species-level assignations of phlebotomine sand flies, our study proves the efficiency of metabarcoding based on the mitochondrial 16S rRNA for studying sand fly diversity from bulk samples. The application of this high-throughput identification procedure to field samples can provide great opportunities for vector monitoring and eco-epidemiological studies.


Subject(s)
DNA Barcoding, Taxonomic/methods , Insect Vectors , Metagenomics/methods , Psychodidae/classification , Psychodidae/genetics , Animals , Cluster Analysis , DNA, Mitochondrial/chemistry , DNA, Mitochondrial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , French Guiana , Phylogeny , Psychodidae/growth & development , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
8.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(6): 4219-4221, 2016 11.
Article in English | MEDLINE | ID: mdl-26000939

ABSTRACT

The nearly complete mitochondrial genome of Lutzomyia umbratilis Ward & Fraiha, 1977 (Psychodidae: Phlebotominae), considered as the main vector of Leishmania guyanensis, is presented. The sequencing has been performed on an Illumina Hiseq 2500 platform, with a genome skimming strategy. The full nuclear ribosomal RNA segment was also assembled. The mitogenome of L. umbratilis was determined to be at least 15,717 bp-long and presents an architecture found in many mitogenomes of insect (13 protein-coding genes, 22 transfer RNAs, two ribosomal RNAs, and one non-coding region also referred as the control region). The control region contains a large repeated element of c. 370 bp and a poly-AT region of unknown length. This is the first mitogenome of Psychodidae to be described.


Subject(s)
Genome, Mitochondrial , Insect Vectors/genetics , Psychodidae/genetics , Animals , Insect Proteins/genetics , Insect Vectors/parasitology , Leishmania guyanensis , Mitochondrial Proteins/genetics , Psychodidae/parasitology , RNA/genetics , RNA, Mitochondrial , RNA, Ribosomal/genetics , RNA, Transfer/genetics
9.
Malar J ; 11: 116, 2012 Apr 17.
Article in English | MEDLINE | ID: mdl-22510395

ABSTRACT

BACKGROUND: Malaria parasites (Plasmodium sp.), including new species, have recently been discovered as low grade mixed infections in three wild chimpanzees (Pan troglodytes schweinfurthii) sampled randomly in Kibale National Park, Uganda. This suggested a high prevalence of malaria infection in this community. The clinical course of malaria in chimpanzees and the species of the vectors that transmit their parasites are not known. The fact that these apes display a specific behaviour in which they consume plant parts of low nutritional value but that contain compounds with anti-malarial properties suggests that the apes health might be affected by the parasite. The avoidance of the night-biting anopheline mosquitoes is another potential behavioural adaptation that would lead to a decrease in the number of infectious bites and consequently malaria. METHODS: Mosquitoes were collected over two years using suction-light traps and yeast-generated CO(2) traps at the nesting and the feeding sites of two chimpanzee communities in Kibale National Park. The species of the female Anopheles caught were then determined and the presence of Plasmodium was sought in these insects by PCR amplification. RESULTS: The mosquito catches yielded a total of 309 female Anopheles specimens, the only known vectors of malaria parasites of mammalians. These specimens belonged to 10 species, of which Anopheles implexus, Anopheles vinckei and Anopheles demeilloni dominated. Sensitive DNA amplification techniques failed to detect any Plasmodium-positive Anopheles specimens. Humidity and trap height influenced the Anopheles capture success, and there was a negative correlation between nest numbers and mosquito abundance. The anopheline mosquitoes were also less diverse and numerous in sites where chimpanzees were nesting as compared to those where they were feeding. CONCLUSIONS: These observations suggest that the sites where chimpanzees build their nests every night might be selected, at least in part, in order to minimize contact with anopheline mosquitoes, which might lead to a reduced risk in acquiring malaria infections.


Subject(s)
Anopheles/classification , Anopheles/parasitology , Malaria/veterinary , Plasmodium/isolation & purification , Primate Diseases/pathology , Animals , Anopheles/growth & development , DNA, Protozoan/genetics , Malaria/parasitology , Malaria/pathology , Plasmodium/genetics , Polymerase Chain Reaction
10.
Med Mycol ; 49(6): 608-11, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21314249

ABSTRACT

A three-year retrospective analysis of fungi isolated from specimens of patients with superficial fungal infections in French Guiana is presented. Clinical samples from 726 patients with presumptive diagnoses of onychomycosis (28.2% of the patients), tinea capitis (27.8%), superficial cutaneous mycoses of the feet (22.0%), and of other areas of the body (21.9%), were assessed by microscopic examination and culture. Dermatophytes accounted for 59.2% of the isolates, followed by yeasts (27.5%) and non-dermatophytic molds (13.1%). Trichophyton rubrum was the most common dermatophyte recovered from cases of onychomycosis (67.4%), tinea pedis (70.6%) and tinea corporis (52.4%). In contrast, Trichophyton tonsurans was the predominant species associated with tinea capitis (73.9%). Yeasts were identified as the principal etiologic agents of onychomycosis of the fingernails (74.2%), whereas molds were found mainly in cases of onychomycosis of the toenails. In such instances, Neoscytalidium dimidiatum (70.8%) was the most common mold recovered in culture. In conclusion, the prevalence of T. rubrum and the occurrence of onychomycosis and fungal infections of the feet in French Guiana are similar to results reported from Europe, whereas the frequency of tinea capitis and the importance of T. tonsurans in such infections are similar to the situation in the Americas.


Subject(s)
Dermatomycoses/epidemiology , Dermatomycoses/microbiology , Fungi/isolation & purification , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , French Guiana/epidemiology , Fungi/cytology , Fungi/growth & development , Humans , Infant , Male , Middle Aged , Prevalence , Retrospective Studies , Young Adult
11.
J Clin Microbiol ; 47(12): 3862-70, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19759217

ABSTRACT

Thirty-eight isolates (including 28 isolates from patients) morphologically identified as Lichtheimia corymbifera (formerly Absidia corymbifera) were studied by sequence analysis (analysis of the internal transcribed spacer [ITS] region of the ribosomal DNA, the D1-D2 region of 28S, and a portion of the elongation factor 1alpha [EF-1alpha] gene). Phenotypic characteristics, including morphology, antifungal susceptibility, and carbohydrate assimilation, were also determined. Analysis of the three loci uncovered two well-delimited clades. The maximum sequence similarity values between isolates from both clades were 66, 95, and 93% for the ITS, 28S, and EF-1alpha loci, respectively, with differences in the lengths of the ITS sequences being detected (763 to 770 bp for isolates of clade 1 versus 841 to 865 bp for isolates of clade 2). Morphologically, the shapes and the sizes of the sporangiospores were significantly different among the isolates from both clades. On the basis of the molecular and morphological data, we considered isolates of clade 2 to belong to a different species named Lichtheimia ramosa because reference strains CBS 269.65 and CBS 270.65 (which initially belonged to Absidia ramosa) clustered within this clade. As neotype A. corymbifera strain CBS 429.75 belongs to clade 1, the name L. corymbifera was conserved for clade 1 isolates. Of note, the amphotericin B MICs were significantly lower for L. ramosa than for L. corymbifera (P < 0.005) but were always

Subject(s)
Absidia/classification , Absidia/genetics , Mucormycosis/microbiology , Absidia/drug effects , Absidia/isolation & purification , Adolescent , Adult , Aged , Aged, 80 and over , Antifungal Agents/pharmacology , DNA, Fungal/analysis , DNA, Ribosomal Spacer/genetics , Female , Humans , Male , Microbial Sensitivity Tests , Middle Aged , Mycological Typing Techniques , Peptide Elongation Factor 1/genetics , Phenotype , RNA, Ribosomal, 28S/genetics , Sequence Analysis, DNA , Species Specificity
12.
Drug Metab Lett ; 3(1): 15-7, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19356112

ABSTRACT

Cerebral malaria (CM) is the most severe complication of Plasmodium falciparum malaria. The aim of this study was to investigate the influence of CM on the cerebral uptake of mefloquine (MQ), in an experimental model of mice infected with Plasmodium berghei ANKA (PbA). Drug diffusion in brain is closely related to efflux pumps such as P-glycoprotein (P-gp/ABCB1/MDR1) and Breast Cancer Resistant Protein (BCRP/ABCG2), two major components of the blood-brain barrier (BBB) which can be modified by inflammation and/or infection. After a single IP dose, MQ concentrations were measured by liquid chromatography in blood and brains of mice infected with Plasmodium berghei ANKA and compared with that of non-infected mice. Our results show that MQ brain concentrations were decreased in CM mice versus healthy mice (0.77 versus 1.31 for brain/plasma concentrations). Although MQ is transported out of endothelial cells by P-glycoprotein, this result cannot be related to this transporter as we have previously shown that CM does not alter P-gp function (personal data). CM induces a reduction of MQ brain transport and, therefore, an increase of central toxicity due to MQ should not be expected during CM.


Subject(s)
Antimalarials/pharmacokinetics , Brain/metabolism , Malaria, Cerebral/metabolism , Mefloquine/pharmacokinetics , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Animals , Blood-Brain Barrier , Chromatography, High Pressure Liquid , Erythrocytes/parasitology , Female , Malaria, Cerebral/parasitology , Mice , Mice, Inbred C57BL , Plasmodium berghei/drug effects
13.
J Parasitol ; 94(5): 1139-42, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18973419

ABSTRACT

Under experimental conditions, Plasmodium berghei infection causes cerebral malaria (CM) in susceptible strains of mice such as C57BL/6 and CBA/Ca, whereas BALB/c or DBA/2J strains serve as a model for CM-resistant mice. The aim of the present study was to investigate the susceptibility of the CF1 mouse strain, carrying a spontaneous mutation of the mdr1a gene, to infection with Plasmodium berghei ANKA (PbA). The mdr1a gene codes for P-glycoprotein (P-gp/ABCB1), an efflux pump that is one of the major components of the blood-brain barrier. P-gp effluxes a broad range of xenobiotics from the brain to blood, preventing accumulation and toxicity in the central nervous system. CFI mdr1a (-/-) mice are used to investigate drug transport by efflux pumps. Because many antimalarial agents are effluxed by P-gp (mefloquine, quinine), it was important to determine whether CF1 mice can develop cerebral malaria to predict drug toxicity during cerebral malaria. Our work showed that CF1 mdr1a (-/-) mice are susceptible to PbA. CF1 and C57BL/6N mice (the reference strain) infected with PbA have similar profiles with regard to clinical signs, brain histological lesions, and brain macrophagic activation observed by immunohistological methods.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B/genetics , Malaria, Cerebral/immunology , Plasmodium berghei/immunology , ATP Binding Cassette Transporter, Subfamily B/physiology , Animals , Brain/pathology , Disease Models, Animal , Disease Susceptibility , Female , Fluorescent Antibody Technique, Indirect , Hemeproteins/analysis , Malaria, Cerebral/genetics , Malaria, Cerebral/parasitology , Mice , Mice, Inbred C57BL , Mice, Mutant Strains , Microglia/pathology , Plasmodium berghei/pathogenicity
14.
J Clin Microbiol ; 46(10): 3237-42, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18701668

ABSTRACT

Debaryomyces hansenii is a hemiascomycetous yeast commonly found in natural substrates and in various types of cheese. Pichia guilliermondii is widely distributed in nature and is a common constituent of the normal human microflora. Both species have been described in human infections but are extremely difficult to differentiate phenotypically. Thus, frequent errors in identification occur. The 62 clinical and environmental isolates sent between 2000 and 2007 to the French National Reference Center for Mycoses and Antifungals as D. hansenii or P. guilliermondii were analyzed by using the carbon assimilation pattern, the presence of pseudohyphae, and sequencing of the ITS and D1/D2 regions of the rRNA gene. The objective of this study was to assess using nucleotide sequences whether phenotypic identification was accurate and whether phenotypic characteristics could be used to differentiate the two species when sequencing was not available. We found that 58% of the isolates were misidentified and belong to seven different species: P. guilliermondii, P. caribbica, P. jadinii, D. hansenii, Candida palmioleophila, C. haemulonii type II, and Clavispora lusitaniae. In conclusion, D. hansenii may not be as common a human pathogen as previously thought. Sequencing of either ITS or D1/D2 regions is a good tool for differentiating the species more frequently confused with D. hansenii, keeping in mind that reliable databases should be used.


Subject(s)
Candida/classification , Candida/genetics , Pichia/classification , Pichia/genetics , Candida/isolation & purification , Candida/physiology , Carbohydrate Metabolism , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Environmental Microbiology , France , Genes, rRNA , Humans , Hyphae/cytology , Molecular Sequence Data , Mycoses/microbiology , Phylogeny , Pichia/isolation & purification , Pichia/physiology , RNA, Fungal/genetics , RNA, Ribosomal/genetics , Sequence Analysis, DNA
15.
Infect Genet Evol ; 8(2): 159-70, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18243814

ABSTRACT

An intraspecific study on Phlebotomus papatasi, the main proven vector of Leishmania major among the members of the subgenus Phlebotomus, was performed. The internal transcribed spacer 2 (ITS 2) of rDNA and the ND4 gene of mt DNA were sequenced from 26 populations from 18 countries (Albania, Algeria, Cyprus, Egypt, Greece, India, Iran, Israel, Italy, Lebanon, Morocco, Saudi Arabia, Spain, Syria, Tunisia, Turkey, Yugoslavia and Yemen), and compared. Samples also included three other species belonging to the subgenus Phlebotomus: P. duboscqi, a proven vector of L. major in the south of Sahara (three populations from Burkina Faso, Kenya and Senegal), P. bergeroti, a suspected vector of L. major (three populations from Oman Sultanate, Iran and Egypt), and one population of P. salehi from Iran. A phylogenetic study was carried out on the subgenus Phlebotomus. Our results confirm the validity of the morphologically characterized taxa. The position of P. salehi is doubtful. Variability in P. papatasi contrasts with that observed within other species having a wide distribution like P. (Paraphlebotomus) sergenti in the Old World or Lutzomyia (Lutzomyia) longipalpis in the New World. Consequently, it could be hypothesized that all populations of P. papatasi over its distribution area have similar vectorial capacities. The limits of the distribution area of L. major are correlated with the distribution of common rodents acting as hosts of the parasites.


Subject(s)
DNA, Mitochondrial/analysis , DNA, Ribosomal Spacer/genetics , Genetic Variation , NADH Dehydrogenase/genetics , Phlebotomus Fever/epidemiology , Phlebotomus/genetics , Animals , Base Sequence , Gene Frequency , Genetics, Population , Geography , Haplotypes , Humans , Phylogeny , Sequence Analysis, DNA
16.
Mem Inst Oswaldo Cruz ; 102(1): 35-40, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17293996

ABSTRACT

Between March 2000 and December 2001 a survey of the sand flies (Diptera: Phlebotominae) of French Guiana was carried out during 14 nights of captures with CDC light-traps and Malaise traps, and resulted in the collection of 2245 individuals of 38 species. The most abundant species were Lutzomyia (Trichophoromyia) ininii Floch & Abonnenc, Lu.(Psychodopygus) squamiventris maripaensis Floch & Abonnenc, and Lu .(Nyssomyia) flaviscutellata Mangabeira. Half of the collected sand flies females were dissected under field conditions and five species were found harboring Leishmania-like parasites. The Leishmania (Kinetoplastidae: Trypanosomatidae) species were identified by molecular typing, and for the first time Lu. (Nys.) flaviscutellata was found harboring Leishmania (Viannia) guyanensis and Lu. (Tri) ininii harboring unknown Leishmania. The first record for French Guiana of Lu. (Psy.) squamiventris maripaensis harboring L. (V.) naiffi, was also reported. The patterns of diversification of the human cutaneous leishmaniasis transmission in French Guiana are discussed.


Subject(s)
Insect Vectors/classification , Psychodidae/classification , Animals , Female , French Guiana , Humans , Insect Vectors/parasitology , Leishmaniasis, Cutaneous/transmission , Male , Population Density , Psychodidae/parasitology , Seasons
17.
Mem. Inst. Oswaldo Cruz ; 102(1): 35-40, Feb. 2007. mapas, graf
Article in English | LILACS | ID: lil-440628

ABSTRACT

Between March 2000 and December 2001 a survey of the sand flies (Diptera: Phlebotominae) of French Guiana was carried out during 14 nights of captures with CDC light-traps and Malaise traps, and resulted in the collection of 2245 individuals of 38 species. The most abundant species were Lutzomyia (Trichophoromyia) ininii Floch & Abonnenc, Lu.(Psychodopygus) squamiventris maripaensis Floch & Abonnenc, and Lu .(Nyssomyia) flaviscutellata Mangabeira. Half of the collected sand flies females were dissected under field conditions and five species were found harboring Leishmania-like parasites. The Leishmania (Kinetoplastidae: Trypanosomatidae) species were identified by molecular typing, and for the first time Lu. (Nys.) flaviscutellata was found harboring Leishmania (Viannia) guyanensis and Lu. (Tri) ininii harboring unknown Leishmania. The first record for French Guiana of Lu. (Psy.) squamiventris maripaensis harboring L. (V.) naiffi, was also reported. The patterns of diversification of the human cutaneous leishmaniasis transmission in French Guiana are discussed.


Subject(s)
Humans , Animals , Male , Female , Insect Vectors/classification , Psychodidae/classification , French Guiana , Insect Vectors/parasitology , Leishmaniasis, Cutaneous/transmission , Population Density , Psychodidae/parasitology , Seasons
18.
Phytother Res ; 21(4): 398-400, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17236172

ABSTRACT

An alkaloidal extract of the leaves of Melochia odorata exhibited antifungal activity against Candida albicans, Cryptococcus neoformans and Saccharomyces cerevisiae using a TLC bioautographic method. Bioassay-guided fractionation of this extract using separation by normal and reverse high-performance liquid chromatography (HPLC) resulted in the isolation of two active compounds identified as frangulanine, a cyclic peptide alkaloid, and waltherione-A, a quinolinone alkaloid.


Subject(s)
Alkaloids/isolation & purification , Antifungal Agents/isolation & purification , Malvaceae/chemistry , Alkaloids/pharmacology , Antifungal Agents/pharmacology , Candida albicans/drug effects , Cryptococcus neoformans/drug effects , Microbial Sensitivity Tests , Plant Leaves/chemistry , Saccharomyces cerevisiae/drug effects
19.
J Clin Microbiol ; 44(2): 340-9, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16455881

ABSTRACT

Mucormycosis is an emerging infection associated with a high mortality rate. Identification of the causative agents remains difficult and time-consuming by standard mycological procedures. In this study, internal transcribed spacer (ITS) sequencing was validated as a reliable technique for identification of Zygomycetes to the species level. Furthermore, species identification directly from infected tissues was evaluated in experimentally infected mice. Fifty-four Zygomycetes strains belonging to 16 species, including the most common pathogenic species of Rhizopus spp., Absidia spp., Mucor spp., and Rhizomucor spp., were used to assess intra- and interspecies variability. Ribosomal DNA including the complete ITS1-5.8S-ITS2 region was amplified with fungal universal primers, sequenced, and compared. Overall, for a given species, sequence similarities between isolates were >98%. In contrast, ITS sequences were very different between species, allowing an accurate identification of Zygomycetes to the species level in most cases. Six species (Rhizopus oryzae, Rhizopus microsporus, Rhizomucor pusillus, Mucor circinelloides, and Mucor indicus) were also used to induce disseminated mucormycosis in mice and to demonstrate that DNA extraction, amplification of fungal DNA, sequencing, and molecular identification were possible directly from frozen tissues.


Subject(s)
Fungi/classification , Fungi/genetics , Mucormycosis/microbiology , Mycological Typing Techniques , Amino Acid Sequence , Animals , Base Sequence , Culture Media , DNA, Fungal/analysis , DNA, Ribosomal Spacer/analysis , Fungi/isolation & purification , Mice , Molecular Sequence Data , Mucorales/classification , Mucorales/genetics , Mucorales/isolation & purification , RNA, Ribosomal, 5.8S , Sequence Analysis, DNA , Species Specificity
20.
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