52 research outputs found
Laboratory and field evaluation of an oviposition trap for Culex quinquefasciatus(Diptera: Culicidae)
Distal Xq duplication and functional Xq disomy
Distal Xq duplications refer to chromosomal disorders resulting from involvement of the long arm of the X chromosome (Xq). Clinical manifestations widely vary depending on the gender of the patient and on the gene content of the duplicated segment. Prevalence of Xq duplications remains unknown. About 40 cases of Xq28 functional disomy due to cytogenetically visible rearrangements, and about 50 cases of cryptic duplications encompassing the MECP2 gene have been reported. The most frequently reported distal duplications involve the Xq28 segment and yield a recognisable phenotype including distinctive facial features (premature closure of the fontanels or ridged metopic suture, broad face with full cheeks, epicanthal folds, large ears, small and open mouth, ear anomalies, pointed nose, abnormal palate and facial hypotonia), major axial hypotonia, severe developmental delay, severe feeding difficulties, abnormal genitalia and proneness to infections. Xq duplications may be caused either by an intrachromosomal duplication or an unbalanced X/Y or X/autosome translocation. In XY males, structural X disomy always results in functional disomy. In females, failure of X chromosome dosage compensation could result from a variety of mechanisms, including an unfavourable pattern of inactivation, a breakpoint separating an X segment from the X-inactivation centre in cis, or a small ring chromosome. The MECP2 gene in Xq28 is the most important dosage-sensitive gene responsible for the abnormal phenotype in duplications of distal Xq. Diagnosis is based on clinical features and is confirmed by CGH array techniques. Differential diagnoses include Prader-Willi syndrome and Alpha thalassaemia-mental retardation, X linked (ATR-X). The recurrence risk is significant if a structural rearrangement is present in one of the parent, the most frequent situation being that of an intrachromosomal duplication inherited from the mother. Prenatal diagnosis is performed by cytogenetic testing including FISH and/or DNA quantification methods. Management is multi-specialist and only symptomatic, with special attention to prevention of malnutrition and recurrent infections. Educational and rehabilitation support should be offered to all patients
Discovery of Markers of Exposure Specific to Bites of Lutzomyia longipalpis, the Vector of Leishmania infantum chagasi in Latin America
Leishmania parasites are transmitted by the bite of an infected vector sand fly that injects salivary molecules into the host skin during feeding. Certain salivary molecules can produce antibodies and can be used as an indicator of exposure to a vector sand fly and potentially the disease it transmits. Here we identified potential markers of specific exposure to the sand fly Lutzomyia longipalpis, the vector of visceral leishmaniasis in Latin America. Initially, we determined which of the salivary proteins produce antibodies in humans, dogs, and foxes from areas endemic for the disease. To identify potential specific markers of vector exposure, we produced nine different recombinant salivary proteins from Lu. longipalpis and tested for their recognition by individuals exposed to another human-biting sand fly, Lu. intermedia, that transmits cutaneous leishmaniasis and commonly occurs in the same endemic areas as Lu. longipalpis. Two of the nine salivary proteins were recognized only by humans exposed to Lu. longipalpis, suggesting they are immunogenic proteins and may be useful in epidemiological studies. The identification of specific salivary proteins as potential markers of exposure to vector sand flies will increase our understanding of vector–human interaction, bring new insights to vector control, and in some instances act as an indicator for risk of acquiring disease
Aedes aegypti, Aedes albopictus, and dengue in Argentina: current knowledge and future directions
Adenovirus-5-Vectored P. falciparum Vaccine Expressing CSP and AMA1. Part B: Safety, Immunogenicity and Protective Efficacy of the CSP Component
Background: A protective malaria vaccine will likely need to elicit both cell-mediated and antibody responses. As adenovirus vaccine vectors induce both these responses in humans, a Phase 1/2a clinical trial was conducted to evaluate the efficacy of an adenovirus serotype 5-vectored malaria vaccine against sporozoite challenge.\ud
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Methodology/Principal Findings: NMRC-MV-Ad-PfC is an adenovirus vector encoding the Plasmodium falciparum 3D7 circumsporozoite protein (CSP). It is one component of a two-component vaccine NMRC-M3V-Ad-PfCA consisting of one adenovector encoding CSP and one encoding apical membrane antigen-1 (AMA1) that was evaluated for safety and immunogenicity in an earlier study (see companion paper, Sedegah et al). Fourteen Ad5 seropositive or negative adults received two doses of NMRC-MV-Ad-PfC sixteen weeks apart, at 1x1010 particle units per dose. The vaccine was safe and well tolerated. All volunteers developed positive ELISpot responses by 28 days after the first immunization (geometric mean 272 spot forming cells/million[sfc/m]) that declined during the following 16 weeks and increased after the second dose to levels that in most cases were less than the initial peak (geometric mean 119 sfc/m). CD8+ predominated over CD4+ responses, as in the first clinical trial. Antibody responses were poor and like ELISpot responses increased after the second immunization but did not exceed the initial peak. Pre-existing neutralizing antibodies (NAb) to Ad5 did not affect the immunogenicity of the first dose, but the fold increase in NAb induced by the first dose was significantly associated with poorer antibody responses after the second dose, while ELISpot responses remained unaffected. When challenged by the bite of P. falciparum-infected mosquitoes, two of 11 volunteers showed a delay in the time to patency compared to infectivity controls, but no volunteers were sterilely protected.\ud
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Significance: The NMRC-MV-Ad-PfC vaccine expressing CSP was safe and well tolerated given as two doses, but did not provide sterile protection
Influence of fire prevention management strategies on the diversity of butterfly fauna in the eastern Pyrenees
Fire prevention management is becoming a necessity in many Mediterranean locations to regulate fire of natural or human origin. However, very few studies have determined the real effects of the strategies adopted on local fauna. Butterflies are sensitive to local changes and they can thus serve as indicators of environmental changes. Three different types of fire prevention management approaches in three different localities in the Eastern Pyrenees (France) were performed and the butterfly community composition was investigated. We show that of the 80 species of butterflies observed, 36 % can be considered as biological markers. An original objective treatment of data using hierarchical distance analysis combined with a neural network analysis (Self-Organizing Maps) was applied in this study. Our conclusions are that the overall number of species is maintained independently of the fire prevention type but that some important changes are observed among butterfly communities, with a clear reduction of the numbers of endemic/specialized species in favour of generalist ones for the two most drastic fire prevention management approaches studied here. The influence of such approaches is discussed on the basis of the conservation of Mediterranean species of Lepidoptera
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