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1.
Nil Rahola Jér?me Depaquit Boris Kevin Makanga Christophe Paupy 《Memórias do Instituto Oswaldo Cruz》2013,108(7):845-849
During a research project aimed at the study of the Culicinae fauna of Gabon and
carried out in the National Park of La Lopé, we captured an unknown sandfly male
specimen (genus Phlebotomus) by CDC miniature light trap
belonging to a new species for Science. Furthermore, the originality of his
genitalia does not allow us to include this species in one of the existing
subgenus, thus in this paper we propose the creation of a new subgenus, as
Phlebotomus (Legeromyia) multihamatus sp. nov., subg. nov.
described from the National Park of La Lopé, through one male captured with CDC
miniature light trap. A new species and a new subgenus of sandfly is
characterised by a short style with three spines, a paramere wearing a basal
hook as well as a basal pouch and the absence of basal lobe on the coxite. The
originality of the genitalia of the male gives way to discussion about potential
primary homologies between P. multihamatus sp. nov. and
Phlebotomus (Abonnencius) fortunatarum, Phlebotomus
(Anaphlebotomus) stantoni and Phlebotomus (Euphlebotomus)
argentipes, which should be verified for future studies. The
discovery of this new species in Gabon must encourage the study of sandflies in
this country. 相似文献
2.
The morphology and ultrastructure of the larval spiracle system of three phlebotomine sandfly species, Phlebotomus perniciosus, P. perfiliewi and P. papatasi, were examined by scanning (SEM) and transmission (TEM) electron microscopy and by confocal scanning laser microscopy (CSLM). During larval development, thoracic and abdominal spiracles show considerable modifications. In fourth instar larvae, the spiracles consist of a plate with a sclerotized central portion and a peripheral circle of papillae. The latter is distinctive in the larvae of P. papatasi, which are readily distinguished from the other species. Opening clefts across the papillae communicate with an internal chamber that encircles an electrondense plug. Many cylindrical projections cross the chamber, uniting the central plug with the larval body, forming an air filter. Spiracular development in successive larval instars has both a taxonomic and adaptive value. 相似文献
3.
Halbig P Hodjati MH Mazloumi-Gavgani AS Mohite H Davies CR 《Medical and veterinary entomology》2000,14(2):223-226
In many foci of zoonotic visceral leishmaniasis (ZVL), domestic dogs are important reservoir hosts of the causative Leishmania parasites transmitted by phlebotomine sandflies (Diptera: Psychodidae). We tested the protective value of impregnated dog collars (20 g plastic containing deltamethrin 800 mg ai) against Phlebotomus papatasi (Scopoli) sandflies in Iran. For each assay, the dog was sedated and caged in a net with 70-100 wild-caught sandflies overnight (23.30-06.30 hours). Dogs wearing the collars were bitten by approximately 80% fewer sandflies than before collars were fitted, i.e. 51% vs. 11% of hungry female flies exposed. Sandfly mortality rates following 20 h exposure to dogs with collars (18%) or without collars (17%) were not significantly different. Effects of collars were tested when dogs had been wearing them for 8 days. A previous trial against the sandfly P. perniciosus Newstead in France, using smaller dogs, showed that effects of such collars were not fully realized until they had been worn for 2 weeks or more; they remained effective for at least 8 months and killed significant proportions of the sandflies exposed. Present results with P. papatasi, confirming that this simple device provides effective protection against sandflies, are considered sufficiently encouraging to justify a community-wide field trial of deltamethrin-impregnated dog collars against ZVL vector sandflies in Iran. 相似文献
4.
Deltamethrin-impregnated bednets reduce human landing rates of sandfly vector Lutzomyia longipalpis in Amazon households 总被引:1,自引:0,他引:1
Courtenay O Gillingwater K Gomes PA Garcez LM Davies CR 《Medical and veterinary entomology》2007,21(2):168-176
The entomological efficacy of using 25% deltamethrin EC insecticide-treated bednets (ITNs) was evaluated against the sandfly Lutzomyia longipalpis Lutz and Neiva (Diptera: Psychodidae), the principal vector of zoonotic visceral leishmaniasis (ZVL) in Latin America. A crossover field study in Amazon Brazil (Marajó Island, Pará State) demonstrated that, compared with untreated nets, the insecticide increased the barrier effect of nets by 39% (95% confidence interval [CI] 34-44%), reduced human landing rates by 80% (95% CI 62-90%) and increased the 24-h mortality rate from 0% to 98% (95% CI 93-99%) inside ITNs. The presence of an ITN also reduced the human landing rate on unprotected persons outside the net in the same room by 56% (95% CI 52-59%), and increased 24-h mortality to 68% (95% CI 62-73%) compared to 0.4% (0.1-2.0%) in untreated houses. The reduction in human landing rates in ITN rooms was associated with a doubling in the proportion of sandflies alighting on walls compared with that in untreated rooms, which was attributed to insecticide-induced excito-repellency. There was no evidence that sandflies were diverted onto unprotected hosts. Human landing catches inside houses peaked between 19.00 hours and 23.00 hours and declined steadily to zero at 02.00 hours and thereafter. House-to-house questionnaires established that only 34% of households owned at least one net (median two, range 1-8), only 20% of the population slept under a net (33% of 0-5-year-old children), and the majority (73%) of the population slept in hammocks. Combined data pertaining to sleeping times for children and sandfly activity period indicate that > 50% of sandfly bites inside houses, and substantially more outside houses, were taken before a third of children were potentially protected by a net. This study demonstrates the clear entomological efficacy of ITNs against Lu. longipalpis in this endemic region. The effectiveness of ITNs at preventing ZVL infection and disease has still to be evaluated. 相似文献
5.
We evaluated the effects of Leishmania spp infection on several
population parameters of Lutzomyia longipalpis sensu lato
andLutzomyia pseudolongipalpis, vectors of visceral leishmaniasis
in Venezuela, under experimental conditions during the first post-feeding period.
Females of both species were allowed to feed and engorge on a suspension of fresh
washed human red blood cells in foetal calf serum. These blood cells were either
non-infected or infected with one of the fourLeishmania spp strains
and were offered through a chicken skin membrane. The longevity, life expectancy and
the fecundity of uninfected flies were similar in both species, but the fertility was
significantly lower in uninfected Lu. longipalpis females. In all
cases, the infection of Lu. longipalpis and Lu.
pseudolongipalpis by the Leishmania strains resulted in
significant detrimental effects, which exerted a fitness cost expressed by reduced
survival and life expectancy, as well as decreased fertility and fecundity compared
with the control groups. Nevertheless, differences in these parameters were observed
between these vector species depending on whether they were infected with the
autochthonous Venezuelan Leishmania infantum strain (NESA) or the
Brazilian reference strain (PP75). The experimental data obtained agree with field
data on the natural infection of these vector species and the significance of this
scenario is discussed. 相似文献
6.
Francinaldo Soares Silva Jefferson Mesquita Brito Benedita Maria Costa Neta Shelre Emile Pereira Duarte Lobo 《Memórias do Instituto Oswaldo Cruz》2015,110(6):801-803
Hoover Pugedo light traps were modified for use with green and blue-light-emitting
diodes to trap phlebotomine sandflies in northeastern Brazil. A total of 2,267
specimens belonging to eight genera and 15 species were sampled. The predominant
species were Nyssomyia whitmani(34.41%) and Micropygomyia
echinatopharynx(17.25%).The green LED trap prevailed over the blue and
control lights; however, no statistically significant difference could be detected
among the three light sources. Even without statistical significance, we suggest
using LEDs as an attractant for the capture of sandflies because of several
advantages over the conventional method with incandescent lamps. 相似文献
7.
Natalia Cadaxo Rochael Luize Gon?alves Lima Sandra Maria Pereira de Oliveira Marcello André Barcinski Elvira Maria Saraiva Robson Queiroz Monteiro Lucia Helena Pinto-da-Silva 《Memórias do Instituto Oswaldo Cruz》2013,108(6):679-685
Leishmania parasites expose phosphatidylserine (PS) on their
surface, a process that has been associated with regulation of host''s immune
responses. In this study we demonstrate that PS exposure by metacyclic
promastigotes of Leishmania amazonensis favours blood
coagulation. L. amazonensis accelerates in vitro coagulation of
human plasma. In addition, L. amazonensis supports the assembly
of the prothrombinase complex, thus promoting thrombin formation. This process
was reversed by annexin V which blocks PS binding sites. During blood meal,
Lutzomyia longipalpis sandfly inject saliva in the bite
site, which has a series of pharmacologically active compounds that inhibit
blood coagulation. Since saliva and parasites are co-injected in the host during
natural transmission, we evaluated the anticoagulant properties of sandfly
saliva in counteracting the procoagulant activity of L.
amazonensis . Lu. longipalpis saliva reverses
plasma clotting promoted by promastigotes. It also inhibits thrombin formation
by the prothrombinase complex assembled either in phosphatidylcholine (PC)/PS
vesicles or in L. amazonensis . Sandfly saliva inhibits factor
X activation by the intrinsic tenase complex assembled on PC/PS vesicles and
blocks factor Xa catalytic activity. Altogether our results show that metacyclic
promastigotes of L. amazonensis are procoagulant due to PS
exposure. Notably, this effect is efficiently counteracted by sandfly
saliva. 相似文献
8.
M. DORA FELICIANGELI JAIME RAMIREZ PEREZ ALIRIO RAMIREZ 《Medical and veterinary entomology》1988,2(1):47-65
Phlebotomine sandflies were surveyed in two ecologically contrasted areas, the northern moist and southern wet tropical forests, of the Territorio Federal Amazonas, Venezuela. Three new taxa and twenty-one new records were added to the previously known species list for Venezuelan sandflies, which now totals eighty species. Both sexes of Lutzomyia (Psychodopygus) killicki sp.n., L. (Trichophoryomyia) bettinii sp.n., L. (Nyssomyia) olmeca reducta subsp.n. and and the females of L. bernalei Osorno et al., Brumptomyia pintoi Costa Lima and L. begonae (Ortiz & Torres) are described and illustrated. 相似文献
9.
Differential application of lambda-cyhalothrin to control the sandfly Lutzomyia longipalpis 总被引:1,自引:0,他引:1
Abstract. To study the impact of residual pyrethroid insecticide on the abundance and distribution of peridomestic Lutzomyia longipalpis , the sandfly vector of visceral leishmaniasis in Brazil, lambda-cyhalothrin was applied at 20 mg a.i.m-2 in the following interventions: (i) spraying of all animal pens in a village (blanket coverage); (ii) treatment of a subset of animal pens, either by spraying, or by installation of insecticide-impregnated 1 m2 cotton sheets as 'targets' (focal coverage).
By sampling with CDC light traps, and using a novel analytical approach, we detected a 90% reduction in Lu. longipalpis abundance in sprayed sheds of the focal intervention. However, there was no discernible effect on the abundance of other phlebotomines trapped in sheds, or on the abundance of Lu. longipalpis in untreated dining-huts and houses. This differential impact on Ludongipalpis abundance is explained in terms of the disruption of male pheromone production. Treated targets were approximately half as effective as residual spraying in reducing the abundance of Lu.longipalpis in sheds.
Following blanket intervention, the abundance of Lu.longipalpis in traps fell by only 45% (not significant): catches at untreated dining-huts actually increased, possibly because the blanket coverage diverted Lu. longipalpis away from major aggregation sites at animal pens. It is recommended that care be taken during vector control programmes to ensure that all potential aggregation sites are treated. The possible consequences of leaving some sites untreated include poor control of peridomestic sandfly abundance and an increase in the biting rate on dogs and humans. 相似文献
By sampling with CDC light traps, and using a novel analytical approach, we detected a 90% reduction in Lu. longipalpis abundance in sprayed sheds of the focal intervention. However, there was no discernible effect on the abundance of other phlebotomines trapped in sheds, or on the abundance of Lu. longipalpis in untreated dining-huts and houses. This differential impact on Ludongipalpis abundance is explained in terms of the disruption of male pheromone production. Treated targets were approximately half as effective as residual spraying in reducing the abundance of Lu.longipalpis in sheds.
Following blanket intervention, the abundance of Lu.longipalpis in traps fell by only 45% (not significant): catches at untreated dining-huts actually increased, possibly because the blanket coverage diverted Lu. longipalpis away from major aggregation sites at animal pens. It is recommended that care be taken during vector control programmes to ensure that all potential aggregation sites are treated. The possible consequences of leaving some sites untreated include poor control of peridomestic sandfly abundance and an increase in the biting rate on dogs and humans. 相似文献
10.
Distribution,species composition and relative abundances of sandflies in North Waziristan Agency,Pakistan
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N. ALI A. ULLAH S. WAHID M. KHISROON S. B. RASHEED 《Medical and veterinary entomology》2016,30(1):89-94
This study was conducted to investigate the diversity of sandflies (Psychodidae: Phlebotominae) and the incidence of leishmaniasis in three villages of North Waziristan Agency, Pakistan. Sandflies were sampled monthly during 2012, at dusk and dawn, in selected indoor habitats including both bedrooms and animal sheds using a knock‐down spray catch method. A total of 3687 sandflies were collected, including 1444 individuals in Drezanda, 1193 in Damdil and 1050 in Dattakhel. This study revealed 14 species of two genera, Phlebotomus (Phlebotomus sergenti, Phlebotomus papatasi, Phlebotomus caucasicus, Phlebotomus kazeruni, Phlebotomus alexandri and Phlebotomus salehi) and Sergentomyia (Sergentomyia dentate, Sergentomyia baghdadis, Sergentomyia babu, Sergentomyia theodori, Sergentomyia sumbarica, Sergentomyia dreyfussitur kestanica, Sergentomyia hogsoni pawlowskyi and Sergentomyia fallax afghanica) (both: Diptera: Psychodidae). Phlebotomus sergenti was the most abundant species (42.1%), followed by S. dentata (17.7%) and S. baghdadis (17.4%). The number of males collected represented about twice that of female flies, and the maximum number was collected in July, followed by August. The determination of the species composition of sandfly populations, seasonal variations, relative abundances and estimations of infection in the vector population may provide information about the dynamics of leishmaniasis transmission that is useful in planning vector control activities. 相似文献