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Sample records for gambiae sensu stricto

  1. Molecular identification of chromosomal forms of Anopheles gambiae sensu stricto.

    PubMed

    Favia, G; Louis, C

    1999-09-01

    The Afrotropical malaria vectors Anopheles gambiae sensu stricto and An. arabiensis, responsible for more than 3/4 of the world Plasmodium falciparum inoculations, are members of the Anopheles gambiae complex, a group consisting of six sibling species. The nominal species (An. gambiae s.s.) is by far the most anthropophilic vector and its adaptation to man and his environment involves further ongoing speciation processes. This fact is shown by the existence of a number of incipient taxonomic units characterised by different chromosomal arrangements derived from the presence of polymorphic paracentric inversions. This speciation process is centered in West Africa, where five so-called 'chromosomal forms' have been described, designated with a non-Linnean nomenclature: Forest, Bissau, Savanna, Bamako, and Mopti. Studies on the distribution and the ecology of these incipient species have highlighted specific adaptations to eco-ethological parameters, which might reflect on their relative efficiency as malaria vectors. Cytogenetic analysis, in spite of some inherent difficulties, has proved to be a powerful tool for the identification of An. gambiae sibling species and the individual chromosomal forms. Yet, modern molecular tools are now available, providing alternative faster low-cost technologies, and we discuss here their relative merits.

  2. Water vapour is a pre-oviposition attractant for the malaria vector Anopheles gambiae sensu stricto

    PubMed Central

    2013-01-01

    Background To date no semiochemicals affecting the pre-oviposition behaviour of the malaria vector Anopheles gambiae sensu lato have been described. Water vapour must be the major chemical signal emanating from a potential larval habitat, and although one might expect that gravid An. gambiae s.l. detect and respond to water vapour in their search for an aquatic habitat, this has never been experimentally confirmed for this species. This study aimed to investigate the role of relative humidity or water vapour as a general cue for inducing gravid An. gambiae sensu stricto to make orientated movements towards the source. Methods Three experiments were carried out with insectary-reared An. gambiae s.s. One with unfed females and two with gravid females during their peak oviposition time in the early evening. First, unfed females and gravid females were tested separately in still air where a humidity difference was established between opposite ends of a WHO bioassay tube and mosquitoes released individually in the centre of the tube. Movement of mosquitoes to either low or high humidity was recorded. Additionally, gravid mosquitoes were released into a larger air-flow olfactometer and responses measured towards collection chambers that contained cups filled with water or empty cups. Results Unfed females equally dispersed in the small bioassay tubes to areas of high and low humidity (mean 50% (95% confidence interval (CI) 38-62%). In contrast, gravid females were 2.4 times (95% CI 1.3-4.7) more likely to move towards high humidity than unfed females. The results were even more pronounced in the airflow olfactometer. Gravid females were 10.6 times (95% CI 5.4-20.8) more likely to enter the chamber with water than a dry chamber. Conclusions Water vapour is a strong pre-oviposition attractant to gravid An. gambiae s.s. in still and moving air and is likely to be a general cue used by mosquitoes for locating aquatic habitats. PMID:24120083

  3. Effectiveness of synthetic versus natural human volatiles as attractants for Anopheles gambiae (Diptera: Culicidae) sensu stricto.

    PubMed

    Smallegange, Renate C; Knols, Bart G J; Takken, Willem

    2010-05-01

    Females of the African malaria vector, Anopheles gambiae Giles sensu stricto, use human volatiles to find their blood-host. Previous work has shown that ammonia, lactic acid, and aliphatic carboxylic acids significantly affect host orientation and attraction of this species. In the current study, these compounds were tested for their attractiveness relative to human emanations in vivo and in vitro. Emanations from a human hand, incubated sweat, and foot skin residues on a nylon sock were significantly attractive when tested against clean air. In a dual-choice test, foot skin residues were significantly more attractive than emanations from a human hand in vivo. Ammonia alone attracted more mosquitoes than fresh or incubated sweat. However, the odor of a human hand or of foot skin residues were more attractive than ammonia. A known attractive blend of ammonia with lactic acid and carboxylic acids was less effective than natural foot odorants. The results demonstrate that the synthetic blend based on skin odor is attractive for An. gambiae, but that in a choice situation in vitro natural skin odors are still preferred by the mosquito. Differences in volatile organic compound abundances between a worn sock and the synthetic blend may have resulted in stronger attraction to the sock. This suggests that candidate attractants should be evaluated with consideration of the strength of natural odorant sources. The data furthermore suggest that additional unidentified compounds from the human foot are involved in the host-seeking behavior of this mosquito species.

  4. Analysing chemical attraction of gravid Anopheles gambiae sensu stricto with modified BG-Sentinel traps.

    PubMed

    Okal, Michael N; Herrera-Varela, Manuela; Ouma, Paul; Torto, Baldwyn; Lindsay, Steven W; Lindh, Jenny M; Fillinger, Ulrike

    2015-06-03

    Cues that guide gravid Anopheles gambiae sensu lato to oviposition sites can be manipulated to create new strategies for monitoring and controlling malaria vectors. However, progress towards identifying such cues is slow in part due to the lack of appropriate tools for investigating long-range attraction to putative oviposition substrates. This study aimed to develop a relatively easy-to-use bioassay system that can effectively analyse chemical attraction of gravid Anopheles gambiae sensu stricto. BG-Sentinel™ mosquito traps that use fans to dispense odourants were modified to contain aqueous substrates. Choice tests with two identical traps set in an 80 m(2) screened semi-field system were used to analyse the catch efficacy of the traps and the effectiveness of the bioassay. A different batch of 200 gravid An. gambiae s.s. was released on every experimental night. Choices tested were (1) distilled versus distilled water (baseline) and (2) distilled water versus soil infusion. Further, comparisons were made of distilled water and soil infusions both containing 150 g/l of Sodium Chloride (NaCl). Sodium Chloride is known to affect the release rate of volatiles from organic substrates. When both traps contained distilled water, 45% (95 confidence interval (CI) 33-57%) of all released mosquitoes were trapped. The proportion increased to 84% (95 CI 73-91%) when traps contained soil infusions. In choice tests, a gravid female was twice as likely to be trapped in the test trap with soil infusion as in the trap with distilled water (odds ratio (OR) 1.8, 95% CI 1.3-2.6). Furthermore, the attraction of gravid females towards the test trap with infusion more than tripled (OR 3.4, 95% CI 2.4-4.8) when salt was added to the substrates. Minor modifications of the BG-Sentinel™ mosquito trap turned it into a powerful bioassay tool for evaluating the orientation of gravid mosquitoes to putative oviposition substrates using olfaction. This study describes a useful tool for

  5. Expression of metallothionein and α-tubulin in heavy metal-tolerant Anopheles gambiae sensu stricto (Diptera: Culicidae)

    PubMed Central

    Mireji, Paul O.; Keating, Joseph; Hassanali, Ahmed; Impoinvil, Daniel E.; Mbogo, Charles M.; Njeri, Martha; Nyambaka, Hudson; Kenya, Eucharia; Githure, John I; Beier, John C.

    2009-01-01

    Anopheles mosquitoes have been shown to adapt to heavy metals in their natural habitats. In this study we explored the possibility of using Anopheles gambiae sensu stricto as bio-reporters for environmental heavy metal pollution through expressions of their metal responsive metallothionein and α-tubulin genes. The study was undertaken with third instar larvae after selection by cadmium, copper, or lead at LC30 through five successive generations. Expression levels were determined in the fifth generation by semi quantitative RT-PCR on the experimental and control populations. The data were analyzed using one-way ANOVA. The highest metallothionein (F3, 11= 4.574, P = 0.038) and α-tubulin (F3,11= 12.961, P = 0.002) responses were observed in cadmium-tolerant treatments. There was significantly higher expression of metallothionein in cadmium or copper treatments relative to the control (P = 0.012), and in cadmium than in lead treatments (P = 0.044). Expressions of α-tubulin were significantly higher in cadmium than in control treatments (P = 0.008). These results demonstrate capacity of An. gambiae s.s. to develop tolerance to increased levels of heavy metal challenge. The results also confirm the potential of heavy metal responsive genes in mosquitoes as possible bio-indicators of heavy metal environmental pollution. How the tolerance and expressions relate to An. gambiae s.s. fitness and vectorial capacity in the environment remains to be elucidated. PMID:19735939

  6. Differential attractiveness of human foot odours to Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) and variation in their chemical composition.

    PubMed

    Omolo, M O; Njiru, B; Ndiege, I O; Musau, R M; Hassanali, A

    2013-10-01

    Counter flow geometry (CFG) traps (American Biophysics) baited with foot odours (adsorbed overnight on a combination of a nylon and a cotton socks) from 4 groups of 4 male volunteers were initially used in a screen-house to compare and grade the attractiveness of Anopheles gambiae Giles sensu stricto to these odours. Ten individuals were then selected from the 4 groups for further grading in which mosquito attractiveness to odours adsorbed on socks worn by each of the individuals was compared against a control (clean, un-worn cotton and nylon socks). A gradation of attractiveness was found, with the most attractive foot odour catching 8-fold more mosquitoes than the least attractive one (t-test, p=0.001). For comparison of the chromatographic profiles of the foot odours and identification of their constituents, six adsorbents (tenax, chromsorb, porapak Q, activated charcoal, reverse phase octadecyl and octyl bonded silica) were evaluated for their suitability in trapping the volatiles in a static mode. Of these, porapak Q was found to be the most effective. Comparison of the gas-chromatographic (GC) and gas chromatography-linked mass spectrometry (GC-MS) profiles of blends collected from the most and least attractive feet on porapak Q adsorbent revealed both qualitative and quantitative differences. The implication of our finding on differential attraction of An. gambiae to their preferred feeding site of different human subjects is highlighted. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Behavioural responses of Anopheles gambiae sensu stricto M and S molecular form larvae to an aquatic predator in Burkina Faso

    PubMed Central

    2012-01-01

    Background Predation of aquatic immature stages has been identified as a major evolutionary force driving habitat segregation and niche partitioning in the malaria mosquito Anopheles gambiae sensu stricto in the humid savannahs of Burkina Faso, West Africa. Here, we explored behavioural responses to the presence of a predator in wild populations of the M and S molecular forms of An. gambiae that typically breed in permanent (e.g., rice field paddies) and temporary (e.g., road ruts) water collections. Methods Larvae used in these experiments were obtained from eggs laid by wild female An. gambiae collected from two localities in south-western Burkina Faso during the 2008 rainy season. Single larvae were observed in an experimental arena, and behavioural traits were recorded and quantified a) in the absence of a predator and b) in the presence of a widespread mosquito predator, the backswimmer Anisops jaczewskii. Differences in the proportion of time allocated to each behaviour were assessed using Principal Component Analysis and Multivariate Analysis of Variance. Results The behaviour of M and S form larvae was found to differ significantly; although both forms mainly foraged at the water surface, spending 60-90% of their time filtering water at the surface or along the wall of the container, M form larvae spent on average significantly more time browsing at the bottom of the container than S form larvae (4.5 vs. 1.3% of their overall time, respectively; P < 0.05). In the presence of a predator, larvae of both forms modified their behaviour, spending significantly more time resting along the container wall (P < 0.001). This change in behaviour was at least twice as great in the M form (from 38.6 to 66.6% of the time at the wall in the absence and presence of the predator, respectively) than in the S form (from 48.3 to 64.1%). Thrashing at the water surface exposed larvae to a significantly greater risk of predation by the notonectid (P < 0.01), whereas predation

  8. Pyriproxyfen for mosquito control: female sterilization or horizontal transfer to oviposition substrates by Anopheles gambiae sensu stricto and Culex quinquefasciatus

    PubMed Central

    2014-01-01

    Background The use of gravid mosquitoes as vehicles to auto-disseminate larvicides was recently demonstrated for the transfer of pyriproxyfen (PPF) by container-breeding Aedes mosquitoes and presents an appealing idea to explore for other disease vectors. The success of this approach depends on the female’s behaviour, the time of exposure and the amount of PPF that can be carried by an individual. We explore the effect of PPF exposure at seven time points around blood feeding on individual Anopheles gambiae sensu stricto and Culex quinquefasciatus fecundity and ability to transfer in laboratory assays. Method Mosquitoes were exposed to 2.6 mg PPF per m2 at 48, 24 and 0.5 hours before and after a blood meal and on the day of egg-laying. The proportion of exposed females (N = 80-100) laying eggs, the number of eggs laid and hatched was studied. Transfer of PPF to oviposition cups was assessed by introducing 10 late instar insectary-reared An. gambiae s.s. larvae into all the cups and monitored for adult emergence inhibition. Results Exposure to PPF between 24 hours before and after a blood meal had significant sterilizing effects: females of both species were 6 times less likely (Odds ratio (OR) 0.16, 95% confidence interval (CI) 0.10-0.26) to lay eggs than unexposed females. Of the few eggs laid, the odds of an egg hatching was reduced 17 times (OR 0.06, 95% CI 0.04-0.08) in Anopheles but only 1.2 times (OR 0.82, 95% CI 0.73-0.93) in Culex. Adult emergence inhibition from larvae introduced in the oviposition cups was observed only from cups in which eggs were laid. When females were exposed to PPF close to egg laying they transferred enough PPF to reduce emergence by 65-71% (95% CI 62-74%). Conclusion PPF exposure within a day before and after blood feeding affects egg-development in An. gambiae s.s. and Cx. quinquefasciatus and presents a promising opportunity for integrated control of vectors and nuisance mosquitoes. However, sterilized females are

  9. The mode of action of spatial repellents and their impact on vectorial capacity of Anopheles gambiae sensu stricto.

    PubMed

    Ogoma, Sheila B; Ngonyani, Hassan; Simfukwe, Emmanuel T; Mseka, Antony; Moore, Jason; Maia, Marta F; Moore, Sarah J; Lorenz, Lena M

    2014-01-01

    Malaria vector control relies on toxicity of insecticides used in long lasting insecticide treated nets and indoor residual spraying. This is despite evidence that sub-lethal insecticides reduce human-vector contact and malaria transmission. The impact of sub-lethal insecticides on host seeking and blood feeding of mosquitoes was measured. Taxis boxes distinguished between repellency and attraction inhibition of mosquitoes by measuring response of mosquitoes towards or away from Transfluthrin coils and humans. Protective effective distance of coils and long-term effects on blood feeding were measured in the semi-field tunnel and in a Peet Grady chamber. Laboratory reared pyrethroid susceptible Anopheles gambiae sensu stricto mosquitoes were used. In the taxis boxes, a higher proportion of mosquitoes (67%-82%) were activated and flew towards the human in the presence of Transfluthrin coils. Coils did not hinder attraction of mosquitoes to the human. In the semi-field Tunnel, coils placed 0.3 m from the human reduced feeding by 86% (95% CI [0.66; 0.95]) when used as a "bubble" compared to 65% (95% CI [0.51; 0.76]) when used as a "point source". Mosquitoes exposed to coils inside a Peet Grady chamber were delayed from feeding normally for 12 hours but there was no effect on free flying and caged mosquitoes exposed in the semi-field tunnel. These findings indicate that airborne pyrethroids minimize human-vector contact through reduced and delayed blood feeding. This information is useful for the development of target product profiles of spatial repellent products that can be used to complement mainstream malaria vector control tools.

  10. The Mode of Action of Spatial Repellents and Their Impact on Vectorial Capacity of Anopheles gambiae sensu stricto

    PubMed Central

    Ogoma, Sheila B.; Ngonyani, Hassan; Simfukwe, Emmanuel T.; Mseka, Antony; Moore, Jason; Maia, Marta F.; Moore, Sarah J.; Lorenz, Lena M.

    2014-01-01

    Malaria vector control relies on toxicity of insecticides used in long lasting insecticide treated nets and indoor residual spraying. This is despite evidence that sub–lethal insecticides reduce human–vector contact and malaria transmission. The impact of sub–lethal insecticides on host seeking and blood feeding of mosquitoes was measured. Taxis boxes distinguished between repellency and attraction inhibition of mosquitoes by measuring response of mosquitoes towards or away from Transfluthrin coils and humans. Protective effective distance of coils and long-term effects on blood feeding were measured in the semi–field tunnel and in a Peet Grady chamber. Laboratory reared pyrethroid susceptible Anopheles gambiae sensu stricto mosquitoes were used. In the taxis boxes, a higher proportion of mosquitoes (67%–82%) were activated and flew towards the human in the presence of Transfluthrin coils. Coils did not hinder attraction of mosquitoes to the human. In the semi–field Tunnel, coils placed 0.3 m from the human reduced feeding by 86% (95% CI [0.66; 0.95]) when used as a “bubble” compared to 65% (95% CI [0.51; 0.76]) when used as a “point source”. Mosquitoes exposed to coils inside a Peet Grady chamber were delayed from feeding normally for 12 hours but there was no effect on free flying and caged mosquitoes exposed in the semi–field tunnel. These findings indicate that airborne pyrethroids minimize human–vector contact through reduced and delayed blood feeding. This information is useful for the development of target product profiles of spatial repellent products that can be used to complement mainstream malaria vector control tools. PMID:25485850

  11. Visual and olfactory associative learning in the malaria vector Anopheles gambiae sensu stricto

    PubMed Central

    2012-01-01

    Background Memory and learning are critical aspects of the ecology of insect vectors of human pathogens because of their potential effects on contacts between vectors and their hosts. Despite this epidemiological importance, there have been only a limited number of studies investigating associative learning in insect vector species and none on Anopheline mosquitoes. Methods A simple behavioural assays was developed to study visual and olfactory associative learning in Anopheles gambiae, the main vector of malaria in Africa. Two contrasted membrane qualities or levels of blood palatability were used as reinforcing stimuli for bi-directional conditioning during blood feeding. Results Under such experimental conditions An. gambiae females learned very rapidly to associate visual (chequered and white patterns) and olfactory cues (presence and absence of cheese or Citronella smell) with the reinforcing stimuli (bloodmeal quality) and remembered the association for up to three days. Associative learning significantly increased with the strength of the conditioning stimuli used. Importantly, learning sometimes occurred faster when a positive reinforcing stimulus (palatable blood) was associated with an innately preferred cue (such as a darker visual pattern). However, the use of too attractive a cue (e.g. Shropshire cheese smell) was counter-productive and decreased learning success. Conclusions The results address an important knowledge gap in mosquito ecology and emphasize the role of associative memory for An. gambiae's host finding and blood-feeding behaviour with important potential implications for vector control. PMID:22284012

  12. Ecological and genetic relationships of the Forest-M form among chromosomal and molecular forms of the malaria vector Anopheles gambiae sensu stricto

    PubMed Central

    Lee, Yoosook; Cornel, Anthony J; Meneses, Claudio R; Fofana, Abdrahamane; Andrianarivo, Aurélie G; McAbee, Rory D; Fondjo, Etienne; Traoré, Sekou F; Lanzaro, Gregory C

    2009-01-01

    Background Anopheles gambiae sensu stricto, one of the principal vectors of malaria, has been divided into two subspecific groups, known as the M and S molecular forms. Recent studies suggest that the M form found in Cameroon is genetically distinct from the M form found in Mali and elsewhere in West Africa, suggesting further subdivision within that form. Methods Chromosomal, microsatellite and geographic/ecological evidence are synthesized to identify sources of genetic polymorphism among chromosomal and molecular forms of the malaria vector Anopheles gambiae s.s. Results Cytogenetically the Forest M form is characterized as carrying the standard chromosome arrangement for six major chromosomal inversions, namely 2La, 2Rj, 2Rb, 2Rc, 2Rd, and 2Ru. Bayesian clustering analysis based on molecular form and chromosome inversion polymorphisms as well as microsatellites describe the Forest M form as a distinct population relative to the West African M form (Mopti-M form) and the S form. The Forest-M form was the most highly diverged of the An. gambiae s.s. groups based on microsatellite markers. The prevalence of the Forest M form was highly correlated with precipitation, suggesting that this form prefers much wetter environments than the Mopti-M form. Conclusion Chromosome inversions, microsatellite allele frequencies and habitat preference all indicate that the Forest M form of An. gambiae is genetically distinct from the other recognized forms within the taxon Anopheles gambiae sensu stricto. Since this study covers limited regions of Cameroon, the possibility of gene flow between the Forest-M form and Mopti-M form cannot be rejected. However, association studies of important phenotypes, such as insecticide resistance and refractoriness against malaria parasites, should take into consideration this complex population structure. PMID:19383163

  13. Chromosomal plasticity and evolutionary potential in the malaria vector Anopheles gambiae sensu stricto: insights from three decades of rare paracentric inversions

    PubMed Central

    2008-01-01

    Background In the Anopheles gambiae complex, paracentric chromosomal inversions are non-randomly distributed along the complement: 18/31 (58%) of common polymorphic inversions are on chromosome arm 2R, which represents only ~30% of the complement. Moreover, in An. gambiae sensu stricto, 6/7 common polymorphic inversions occur on 2R. Most of these inversions are considered markers of ecological adaptation that increase the fitness of the carriers of alternative karyotypes in contrasting habitats. However, little is known about the evolutionary forces responsible for their origin and subsequent establishment in field populations. Results Here, we present data on 82 previously undescribed rare chromosomal inversions (RCIs) recorded during extensive field sampling in 16 African countries over a 30 year period, which may shed light on the dynamics of chromosomal plasticity in An. gambiae. We analyzed breakpoint distribution, length, and geographic distribution of RCIs, and compared these measures to those of the common inversions. We found that RCIs, like common inversions, are disproportionately clustered on 2R, which may indicate that this arm is especially prone to breakages. However, contrasting patterns were observed between the geographic distribution of common inversions and RCIs. RCIs were equally frequent across biomes and on both sides of the Great Rift Valley (GRV), whereas common inversions predominated in arid ecological settings and west of the GRV. Moreover, the distribution of RCI lengths followed a random pattern while common inversions were significantly less frequent at shorter lengths. Conclusion Because 17/82 (21%) RCIs were found repeatedly at very low frequencies – at the same sampling location in different years and/or in different sampling locations – we suggest that RCIs are subject mainly to drift under unperturbed ecological conditions. Nevertheless, RCIs may represent an important reservoir of genetic variation for An. gambiae in

  14. Genetic and environmental factors associated with laboratory rearing affect survival and assortative mating but not overall mating success in Anopheles gambiae sensu stricto.

    PubMed

    Paton, Doug; Touré, Mahamoudou; Sacko, Adama; Coulibaly, Mamadou B; Traoré, Sékou F; Tripet, Frédéric

    2013-01-01

    Anopheles gambiae sensu stricto, the main vector of malaria in Africa, is characterized by its vast geographical range and complex population structure. Assortative mating amongst the reproductively isolated cryptic forms that co-occur in many areas poses unique challenges for programs aiming to decrease malaria incidence via the release of sterile or genetically-modified mosquitoes. Importantly, whether laboratory-rearing affects the ability of An. gambiae individuals of a given cryptic taxa to successfully mate with individuals of their own form in field conditions is still unknown and yet crucial for mosquito-releases. Here, the independent effects of genetic and environmental factors associated with laboratory rearing on male and female survival, mating success and assortative mating were evaluated in the Mopti form of An. gambiae over 2010 and 2011. In semi-field enclosures experiments and despite strong variation between years, the overall survival and mating success of male and female progeny from a laboratory strain was not found to be significantly lower than those of the progeny of field females from the same population. Adult progeny from field-caught females reared at the larval stage in the laboratory and from laboratory females reared outdoors exhibited a significant decrease in survival but not in mating success. Importantly, laboratory individuals reared as larvae indoors were unable to mate assortatively as adults, whilst field progeny reared either outdoors or in the laboratory, as well as laboratory progeny reared outdoors all mated significantly assortatively. These results highlight the importance of genetic and environment interactions for the development of An. gambiae's full mating behavioral repertoire and the challenges this creates for mosquito rearing and release-based control strategies.

  15. Behavioural responses of Anopheles gambiae sensu stricto to components of human breath, sweat and urine depend on mixture composition and concentration.

    PubMed

    Qiu, Y T; Smallegange, R C; VAN Loon, J J A; Takken, W

    2011-09-01

    Host-seeking behaviour of the anthropophilic malaria vector Anopheles gambiae sensu stricto (Diptera: Culicidae) is mediated predominantly by olfactory cues. Several hundreds of odour components have been identified from human emanations, but only a few have been proven to act as attractants or synergists in the host-seeking behaviour of female An. gambiae. In previous work, aromatics, alcohols and ketones in human odours were found to elicit electrophysiological activity in antennal olfactory neurons of female An. gambiae. However, the behavioural effects of these compounds have not been investigated. In this study, behavioural responses of female An. gambiae to components of human breath, urine and sweat at a series of concentrations, or a single concentration in the case of acetone, were examined in combination with ammonia and L-lactic acid in a dual-choice olfactometer. The results showed that at specific concentrations 4-ethylphenol, indole, 3-methyl-1-butanol and two ketones inhibited the attractive effect of a mixture of ammonia and lactic acid. Acetone on its own was not attractive; however, when combined with lactic acid, the binary mixture was attractive. When combined with ammonia, acetone inhibited the attractiveness exerted by ammonia alone. Dodecanol and dimethyldisulphide did not affect the attraction exerted by ammonia and lactic acid at any of the concentrations tested. By contrast, a human-specific armpit odour, 7-octenoic acid, augmented the attraction exerted by the combination of ammonia and lactic acid at a specific dosage. © 2010 The Authors. Medical and Veterinary Entomology © 2010 The Royal Entomological Society.

  16. Aquatain® Mosquito Formulation (AMF) for the control of immature Anopheles gambiae sensu stricto and Anopheles arabiensis: dose-responses, persistence and sub-lethal effects.

    PubMed

    Mbare, Oscar; Lindsay, Steven W; Fillinger, Ulrike

    2014-09-16

    Persistent monomolecular surface films could benefit larval source management for malaria control by reducing programme costs and managing insecticide resistance. This study evaluated the efficacy of the silicone-based surface film, Aquatain® Mosquito Formulation (AMF), for the control of the Afrotropical malaria vectors, Anopheles gambiae sensu stricto and Anopheles arabiensis in laboratory dose-response assays and standardized field tests. Tests were carried out following guidelines made by the World Health Organization Pesticide Evaluation Scheme (WHOPES). Sub-lethal effects of AMF were evaluated by measuring egg-laying and hatching of eggs laid by female An. gambiae s.s. that emerged from habitats treated with a dose that resulted in 50% larval mortality in laboratory tests. Both vector species were highly susceptible to AMF. The estimated lethal doses to cause complete larval mortality in dose-response tests in the laboratory were 1.23 (95% confidence interval (CI) 0.99-1.59) ml/m2 for An. gambiae s.s. and 1.35 (95% CI 1.09-1.75) ml/m2 for An. arabiensis. Standardized field tests showed that a single dose of AMF at 1 ml/m2 inhibited emergence by 85% (95% CI 82-88%) for six weeks. Females exposed as larvae to a sub-lethal dose of AMF were 2.2 times less likely (Odds ratio (OR) 0.45, 95% CI 0.26-0.78) to lay eggs compared to those from untreated ponds. However, exposure to sub-lethal doses neither affected the number of eggs laid by females nor the proportion hatching. AMF provided high levels of larval control for a minimum of six weeks, with sub-lethal doses reducing the ability of female mosquitoes to lay eggs. The application of AMF provides a promising novel strategy for larval control interventions against malaria vectors in Africa. Further field studies in different eco-epidemiological settings are justified to determine the persistence of AMF film for mosquito vector control and its potential for inclusion in integrated vector management programmes.

  17. A 3D Analysis of Flight Behavior of Anopheles gambiae sensu stricto Malaria Mosquitoes in Response to Human Odor and Heat

    PubMed Central

    Spitzen, Jeroen; Spoor, Cornelis W.; Grieco, Fabrizio; ter Braak, Cajo; Beeuwkes, Jacob; van Brugge, Sjaak P.; Kranenbarg, Sander; Noldus, Lucas P. J. J.; van Leeuwen, Johan L.; Takken, Willem

    2013-01-01

    Female mosquitoes use odor and heat as cues to navigate to a suitable landing site on their blood host. The way these cues affect flight behavior and modulate anemotactic responses, however, is poorly understood. We studied in-flight behavioral responses of females of the nocturnal malaria mosquito Anopheles gambiae sensu stricto to human odor and heat. Flight-path characteristics in a wind tunnel (flow 20 cm/s) were quantified in three dimensions. With wind as the only stimulus (control), short and close to straight upwind flights were recorded. With heat alone, flights were similarly short and direct. The presence of human odor, in contrast, caused prolonged and highly convoluted flight patterns. The combination of odor+heat resulted in longer flights with more landings on the source than to either cue alone. Flight speed was greatest (mean groundspeed 27.2 cm/s) for odor+heat. Odor alone resulted in decreased flight speed when mosquitoes arrived within 30 cm of the source whereas mosquitoes exposed to odor+heat maintained a high flight speed while flying in the odor plume, until they arrived within 15 cm of the source. Human odor evoked an increase in crosswind flights with an additive effect of heat at close range (<15 cm) to the source. This was found for both horizontal and vertical flight components. However, mosquitoes nevertheless made upwind progress when flying in the odor+heat generated plume, suggesting that mosquitoes scan their environment intensively while they progress upwind towards their host. These observations may help to improve the efficacy of trapping systems for malaria mosquitoes by (1) optimizing the site of odor release relative to trap entry and (2) adding a heat source which enhances a landing response. PMID:23658792

  18. Modeling the role of environmental variables on the population dynamics of the malaria vector Anopheles gambiae sensu stricto.

    PubMed

    Parham, Paul E; Pople, Diane; Christiansen-Jucht, Céline; Lindsay, Steve; Hinsley, Wes; Michael, Edwin

    2012-08-09

    The impact of weather and climate on malaria transmission has attracted considerable attention in recent years, yet uncertainties around future disease trends under climate change remain. Mathematical models provide powerful tools for addressing such questions and understanding the implications for interventions and eradication strategies, but these require realistic modeling of the vector population dynamics and its response to environmental variables. Published and unpublished field and experimental data are used to develop new formulations for modeling the relationships between key aspects of vector ecology and environmental variables. These relationships are integrated within a validated deterministic model of Anopheles gambiae s.s. population dynamics to provide a valuable tool for understanding vector response to biotic and abiotic variables. A novel, parsimonious framework for assessing the effects of rainfall, cloudiness, wind speed, desiccation, temperature, relative humidity and density-dependence on vector abundance is developed, allowing ease of construction, analysis, and integration into malaria transmission models. Model validation shows good agreement with longitudinal vector abundance data from Tanzania, suggesting that recent malaria reductions in certain areas of Africa could be due to changing environmental conditions affecting vector populations. Mathematical models provide a powerful, explanatory means of understanding the role of environmental variables on mosquito populations and hence for predicting future malaria transmission under global change. The framework developed provides a valuable advance in this respect, but also highlights key research gaps that need to be resolved if we are to better understand future malaria risk in vulnerable communities.

  19. Modeling the role of environmental variables on the population dynamics of the malaria vector Anopheles gambiae sensu stricto

    PubMed Central

    2012-01-01

    Background The impact of weather and climate on malaria transmission has attracted considerable attention in recent years, yet uncertainties around future disease trends under climate change remain. Mathematical models provide powerful tools for addressing such questions and understanding the implications for interventions and eradication strategies, but these require realistic modeling of the vector population dynamics and its response to environmental variables. Methods Published and unpublished field and experimental data are used to develop new formulations for modeling the relationships between key aspects of vector ecology and environmental variables. These relationships are integrated within a validated deterministic model of Anopheles gambiae s.s. population dynamics to provide a valuable tool for understanding vector response to biotic and abiotic variables. Results A novel, parsimonious framework for assessing the effects of rainfall, cloudiness, wind speed, desiccation, temperature, relative humidity and density-dependence on vector abundance is developed, allowing ease of construction, analysis, and integration into malaria transmission models. Model validation shows good agreement with longitudinal vector abundance data from Tanzania, suggesting that recent malaria reductions in certain areas of Africa could be due to changing environmental conditions affecting vector populations. Conclusions Mathematical models provide a powerful, explanatory means of understanding the role of environmental variables on mosquito populations and hence for predicting future malaria transmission under global change. The framework developed provides a valuable advance in this respect, but also highlights key research gaps that need to be resolved if we are to better understand future malaria risk in vulnerable communities. PMID:22877154

  20. An age-size reaction norm yields insight into environmental interactions affecting life-history traits: a factorial study of larval development in the malaria mosquito Anopheles gambiae sensu stricto.

    PubMed

    Phelan, Conan; Rotiberg, Bernard D

    2013-07-01

    Environmental factors frequently act nonindependently to determine growth and development of insects. Because age and size at maturity strongly influence population dynamics, interaction effects among environmental variables complicate the task of predicting dynamics of insect populations under novel conditions. We reared larvae of the African malaria mosquito Anopheles gambiae sensu stricto (s.s.) under three factors relevant to changes in climate and land use: food level, water depth, and temperature. Each factor was held at two levels in a fully crossed design, for eight experimental treatments. Larval survival, larval development time, and adult size (wing length) were measured to indicate the importance of interaction effects upon population-level processes. For age and size at emergence, but not survival, significant interaction effects were detected for all three factors, in addition to sex. Some of these interaction effects can be understood as consequences of how the different factors influence energy usage in the context of a nonindependent relationship between age and size. Experimentally assessing interaction effects for all potential future sets of conditions is intractable. However, considering how different factors affect energy usage within the context of an insect's evolved developmental program can provide insight into the causes of complex environmental effects on populations.

  1. Green tea proanthocyanidins cause impairment of hormone-regulated larval development and reproductive fitness via repression of juvenile hormone acid methyltransferase, insulin-like peptide and cytochrome P450 genes in Anopheles gambiae sensu stricto.

    PubMed

    Muema, Jackson M; Nyanjom, Steven G; Mutunga, James M; Njeru, Sospeter N; Bargul, Joel L

    2017-01-01

    Successful optimization of plant-derived compounds into control of nuisance insects would benefit from scientifically validated targets. However, the close association between the genotypic responses and physiological toxicity effects mediated by these compounds remains underexplored. In this study, we evaluated the sublethal dose effects of proanthocyanidins (PAs) sourced from green tea (Camellia sinensis) on life history traits of Anopheles gambiae (sensu stricto) mosquitoes with an aim to unravel the probable molecular targets. Based on the induced phenotypic effects, genes selected for study targeted juvenile hormone (JH) biosynthesis, signal transduction, oxidative stress response and xenobiotic detoxification in addition to vitellogenesis in females. Our findings suggest that chronic exposure of larval stages (L3/L4) to sublethal dose of 5 ppm dramatically extended larval developmental period for up to 12 days, slowed down pupation rates, induced abnormal larval-pupal intermediates and caused 100% inhibition of adult emergence. Further, females exhibited significant interference of fecundity and egg hatchability relative to controls (p < 0.001). Using reverse transcription quantitative polymerase chain reaction (RT-qPCR), our findings show that PA-treated larvae exhibited significant repression of AgamJHAMT (p < 0.001), AgamILP1 (p < 0.001) and AgamCYP6M2 (p < 0.001) with up-regulation of Hsp70 (p < 0.001). Females exposed as larvae demonstrated down-regulation of AgamVg (p = 0.03), AgamILP1 (p = 0.009), AgamCYP6M2 (p = 0.05) and AgamJHAMT (p = 0.02). Our findings support that C. sinensis proanthocyanidins affect important vectorial capacity components such as mosquito survival rates and reproductive fitness thus could be potentially used for controlling populations of malaria vectors.

  2. Green tea proanthocyanidins cause impairment of hormone-regulated larval development and reproductive fitness via repression of juvenile hormone acid methyltransferase, insulin-like peptide and cytochrome P450 genes in Anopheles gambiae sensu stricto

    PubMed Central

    Nyanjom, Steven G.; Mutunga, James M.; Njeru, Sospeter N.; Bargul, Joel L.

    2017-01-01

    Successful optimization of plant-derived compounds into control of nuisance insects would benefit from scientifically validated targets. However, the close association between the genotypic responses and physiological toxicity effects mediated by these compounds remains underexplored. In this study, we evaluated the sublethal dose effects of proanthocyanidins (PAs) sourced from green tea (Camellia sinensis) on life history traits of Anopheles gambiae (sensu stricto) mosquitoes with an aim to unravel the probable molecular targets. Based on the induced phenotypic effects, genes selected for study targeted juvenile hormone (JH) biosynthesis, signal transduction, oxidative stress response and xenobiotic detoxification in addition to vitellogenesis in females. Our findings suggest that chronic exposure of larval stages (L3/L4) to sublethal dose of 5 ppm dramatically extended larval developmental period for up to 12 days, slowed down pupation rates, induced abnormal larval-pupal intermediates and caused 100% inhibition of adult emergence. Further, females exhibited significant interference of fecundity and egg hatchability relative to controls (p < 0.001). Using reverse transcription quantitative polymerase chain reaction (RT-qPCR), our findings show that PA-treated larvae exhibited significant repression of AgamJHAMT (p < 0.001), AgamILP1 (p < 0.001) and AgamCYP6M2 (p < 0.001) with up-regulation of Hsp70 (p < 0.001). Females exposed as larvae demonstrated down-regulation of AgamVg (p = 0.03), AgamILP1 (p = 0.009), AgamCYP6M2 (p = 0.05) and AgamJHAMT (p = 0.02). Our findings support that C. sinensis proanthocyanidins affect important vectorial capacity components such as mosquito survival rates and reproductive fitness thus could be potentially used for controlling populations of malaria vectors. PMID:28301607

  3. Systematics of the Gomphales: the genus Gomphus sensu stricto

    Treesearch

    Admir J. Giachini; Carla M. Camelini; Márcia J Rossi; Cláudio R.F.S. Soares; James M. Trappe

    2012-01-01

    Gomphus sensu lato (Gomphales) was described to include species of cantharelloid-gomphoid fungi that had “merulioid” (wrinkled) hymenia and verrucose spores. Gomphus sensu stricto is currently characterized by unipileate to merismatoid (composed of several pilei) basidiomata, depressed funnel- to fan-shaped...

  4. Effects of food, water depth, and temperature on diving activity of larval Anopheles gambiae sensu stricto: evidence for diving to forage.

    PubMed

    Phelan, Conan; Roitberg, Bernard D

    2013-12-01

    Anopheles gambiae larvae have frequently been observed to dive, but the ecology of this behavior has not been extensively examined. We manipulated food level, water depth, and temperature for individually-reared larvae and observed diving activity. Larvae dived more often under low food, which suggests that they dive to forage. There was only weak evidence for effects of water depth or temperature on diving. Experimental results are discussed in the context of energy budgets. Understanding larval ecology of this species is important for predicting how it will respond to environmental change. Further study is needed to assess the role that larval diving plays in both feeding ecology and thermal regulation of this and other medically important species. © 2013 The Society for Vector Ecology.

  5. Genomic Insights into the Saccharomyces sensu stricto Complex

    PubMed Central

    Borneman, Anthony R.; Pretorius, Isak S.

    2015-01-01

    The Saccharomyces sensu stricto group encompasses species ranging from the industrially ubiquitous yeast Saccharomyces cerevisiae to those that are confined to geographically limited environmental niches. The wealth of genomic data that are now available for the Saccharomyces genus is providing unprecedented insights into the genomic processes that can drive speciation and evolution, both in the natural environment and in response to human-driven selective forces during the historical “domestication” of these yeasts for baking, brewing, and winemaking. PMID:25657346

  6. High intraspecific variability of Echinococcus granulosus sensu stricto in Chile.

    PubMed

    Alvarez Rojas, Cristian A; Ebi, Dennis; Paredes, Rodolfo; Acosta-Jamett, Gerardo; Urriola, Nicole; Roa, Juan Carlos; Manterola, Carlos; Cortes, Sandra; Romig, Thomas; Scheerlinck, Jean-Pierre; Lightowlers, Marshall W

    2017-04-01

    Echinococcus granulosus sensu stricto is the major cause of cystic echinococcosis in most human and animal cases in the world and the most widespread species within the E. granulosus sensu lato complex. E. granulosus s.s. remains endemic in South America together with other species of the Echinococcus genus, especially in some areas in Argentina, Brazil, Chile and Peru. Except for a single human case caused by E. canadensis (G6) described in the literature, only E. granulosus s.s. has been found in the Chilean territory. In the current study 1609bp of the cox1 gene from 69 Chilean isolates of E. granulosus s.s. from humans and animals were analysed. In total, 26 cox1 haplotypes were found, including the widespread haplotype EG01 (22 isolates) and also EGp1 (5), EgRUS7 (1), EgAus02 (1) and EgAus03 (2). Twenty-one different haplotype not previously described were identified from 38 Chilean isolates designated EgCL1-EgCL21. Previous work had described low variability of E. granulosus s.s. in South America, based on isolates from Peru. Results obtained in this work challenge the previously described idea of the low diversity of the parasite in South America, and warrant future investigation on the origin and spread of the parasite in the continent after the Spanish arrival. Copyright © 2016. Published by Elsevier B.V.

  7. Microdiversity of Echinococcus granulosus sensu stricto in Australia.

    PubMed

    Alvarez Rojas, C A; Ebi, D; Gauci, C G; Scheerlinck, J P; Wassermann, M; Jenkins, D J; Lightowlers, M W; Romig, T

    2016-07-01

    Echinococcus granulosus (sensu lato) is now recognized as an assemblage of cryptic species, which differ considerably in morphology, development, host specificity (including infectivity/pathogenicity for humans) and other aspects. One of these species, E. granulosus sensu stricto (s.s.), is now clearly identified as the principal agent causing cystic echinococcosis in humans. Previous studies of a small section of the cox1 and nadh1 genes identified two variants of E. granulosus s.s. to be present in Australia; however, no further work has been carried out to characterize the microdiversity of the parasite in its territory. We have analysed the sequence of the full length of the cox1 gene (1609 bp) from 37 isolates of E. granulosus from different hosts and geographic regions of Australia. The analysis shows that seven haplotypes of E. granulosus s.s. not previously described were found, together with five haplotypes known to be present in other parts of the world, including the haplotype EG01 which is widespread and present in all endemic regions. These data extend knowledge related to the geographical spread and host range of E. granulosus s.s. in a country such as Australia in which the parasite established around 200 years ago.

  8. [Pedagogical training in stricto sensu graduate programs in public health].

    PubMed

    Corrêa, Guilherme Torres; Ribeiro, Victoria Maria Brant

    2013-06-01

    The scope of this research is to discuss the relevance and need for pedagogical training of university lecturers in the Public Health field. The contention is that college teaching is a practice that requires specific training, since it is characterized by complex elements that transcend the mastery of given content. Considering stricto sensu graduate studies as an important stage in the training of future university lecturers, an attempt was made to identify and analyze the subjects and practices of pedagogical training in academic masters and doctorate programs in Public Health. To achieve the research aim, this work was based on Pierre Bourdieu's field theory and on Tomaz Tadeu da Silva's curriculum theory. Results indicate that the programs do not consider the aspect of teacher training as a major issue. With regard to the Public Health field approximately 61% of masters and 38% of doctorate programs have pedagogical training subjects/practices. Furthermore, there is a tendency for technical-instrumental training, which is in line with the history of the Public Health field. The conclusion is that there is a need to develop a culture that values college and graduate Public Health teaching, considering the complexity of pedagogical practice in all its dimensions.

  9. Testing the taxonomic integrity of Paranthropus boisei sensu stricto.

    PubMed

    Silverman, N; Richmond, B; Wood, B

    2001-06-01

    The craniodental hypodigm of Paranthropus boisei sensu stricto is morphologically distinctive, but it has been suggested that the substantial variation in mandibular and dental size in that hypodigm may exceed that which is reasonable to subsume within a single hominin species. In this study, Fligner and Killeen, coefficient of variation (CV)-based and average taxonomic distance (ATD)-based bootstrap tests, were used to compare variation in size and shape of the mandibular corpus remains attributed to P. boisei s.s. with the variation observed in samples of great apes and modern humans. The degree of size variation in the P. boisei s.s. mandibular hypodigm is never observed in human and chimpanzee samples, is rare in gorillas, but is not uncommon in orangutans. However, the shape variation in the fossil group is comparable to the variation in the extant reference groups. Although the size variation in P. boisei s.s. is substantial, it is exaggerated by the effects of taphonomy. The small mandibles are more often abraded, whereas the large mandibles are more likely to have been infiltrated with matrix. On the basis of the results of this investigation of the mandibular corpus, there are no grounds for rejecting the "single-species" hypothesis for P. boisei s.s. When Sokal and Braumann's adjusted CV values were used to predict the index of sexual dimorphism (ISD) for the P. boisei s.s., despite the substantial geological time embraced by the mandibular corpus hypodigm, the predicted value of lnISD, when corrected for taphonomic factors, is comparable to the sexual dimorphism observed within Gorilla.

  10. [Serological diagnosis of sporotrichosis using an antigen of Sporothrix schenckii sensu stricto mycelium].

    PubMed

    Alvarado, Primavera; Ostos, Ana; Franquiz, Nohelys; Roschman-González, Antonio; Zambrano, Edgar A; Mendoza, Mireya

    2015-06-01

    We developed and analyzed an Enzyme-Linked Immunosorbent Assay (ELISA) in order to detect antibodies in sera from sporotrichosis patients. We used a crude antigen of Sporothrix schenckii sensu stricto, obtained from the mycelial phase of the fungi. Positive sera were analyzed by other serological techniques such as double immunodiffusion (IGG) and counterimmunoelectrophoresis (CIE). The assay was validated by using sera from patients with other pathologies such as: histoplasmosis, paracoccidioidomycosis, tuberculosis, leishmaniasis, lupus and healthy individuals as negative controls. For the Sporothrix schenckii sensu stricto antigen, we found a 100% of specificity by every technique and sensitivity higher than 98% with IDD, CIE and ELISA. Our results show a high sensitivity and specificity for the Sporothrix schenckii sensu stricto antigen, so it can be used for IDD, CIE and ELISA. The results suggest that this antigen could be used in conjunction with other conventional tests for differential diagnosis and may be useful for monitoring the disease progression and response to treatment.

  11. Sporothrix schenckii sensu stricto and Sporothrix brasiliensis Are Differentially Recognized by Human Peripheral Blood Mononuclear Cells.

    PubMed

    Martínez-Álvarez, José A; Pérez-García, Luis A; Mellado-Mojica, Erika; López, Mercedes G; Martínez-Duncker, Iván; Lópes-Bezerra, Leila M; Mora-Montes, Héctor M

    2017-01-01

    Sporothrix schenckii sensu stricto and S. brasiliensis are usually associated to sporotrichosis, a subcutaneous mycosis worldwide distributed. Comparative analyses between these two species indicate they contain genetic and physiological differences that are likely to impact the interaction with host cells. Here, we study the composition of the cell wall from conidia, yeast-like cells and germlings of both species and found they contained the same sugar composition. The carbohydrate proportion in the S. schenckii sensu stricto wall was similar across the three cell morphologies, with exception in the chitin content, which was significantly different in the three morphologies. The cell wall from germlings showed lower rhamnose content and higher glucose levels than other cell morphologies. In S. brasiliensis, the wall sugars were constant in the three morphologies, but glucose was lower in yeast-like cells. In S. schenckii sensu stricto cells most of chitin and β1,3-glucan were underneath wall components, but in S. brasiliensis germlings, chitin was exposed at the cell surface, and β1,3-glucan was found in the outer part of the conidia wall. We also compared the ability of these cells to stimulate cytokine production by human peripheral blood mononuclear cells. The three S. schenckii sensu stricto morphologies stimulated increased levels of pro-inflammatory cytokines, when compared to S. brasiliensis cells; while the latter, with exception of conidia, stimulated higher IL-10 levels. Dectin-1 was a key receptor for cytokine production during stimulation with the three morphologies of S. schenckii sensu stricto, but dispensable for cytokine production stimulated by S. brasiliensis germlings. TLR2 and TLR4 were also involved in the sensing of Sporothrix cells, with a major role for the former during cytokine stimulation. Mannose receptor had a minor contribution during cytokine stimulation by S. schenckii sensu stricto yeast-like cells and germlings, but S. schenckii

  12. Sporothrix schenckii sensu stricto and Sporothrix brasiliensis Are Differentially Recognized by Human Peripheral Blood Mononuclear Cells

    PubMed Central

    Martínez-Álvarez, José A.; Pérez-García, Luis A.; Mellado-Mojica, Erika; López, Mercedes G.; Martínez-Duncker, Iván; Lópes-Bezerra, Leila M.; Mora-Montes, Héctor M.

    2017-01-01

    Sporothrix schenckii sensu stricto and S. brasiliensis are usually associated to sporotrichosis, a subcutaneous mycosis worldwide distributed. Comparative analyses between these two species indicate they contain genetic and physiological differences that are likely to impact the interaction with host cells. Here, we study the composition of the cell wall from conidia, yeast-like cells and germlings of both species and found they contained the same sugar composition. The carbohydrate proportion in the S. schenckii sensu stricto wall was similar across the three cell morphologies, with exception in the chitin content, which was significantly different in the three morphologies. The cell wall from germlings showed lower rhamnose content and higher glucose levels than other cell morphologies. In S. brasiliensis, the wall sugars were constant in the three morphologies, but glucose was lower in yeast-like cells. In S. schenckii sensu stricto cells most of chitin and β1,3-glucan were underneath wall components, but in S. brasiliensis germlings, chitin was exposed at the cell surface, and β1,3-glucan was found in the outer part of the conidia wall. We also compared the ability of these cells to stimulate cytokine production by human peripheral blood mononuclear cells. The three S. schenckii sensu stricto morphologies stimulated increased levels of pro-inflammatory cytokines, when compared to S. brasiliensis cells; while the latter, with exception of conidia, stimulated higher IL-10 levels. Dectin-1 was a key receptor for cytokine production during stimulation with the three morphologies of S. schenckii sensu stricto, but dispensable for cytokine production stimulated by S. brasiliensis germlings. TLR2 and TLR4 were also involved in the sensing of Sporothrix cells, with a major role for the former during cytokine stimulation. Mannose receptor had a minor contribution during cytokine stimulation by S. schenckii sensu stricto yeast-like cells and germlings, but S. schenckii

  13. Genome Sequence of Helicobacter heilmannii Sensu Stricto ASB1 Isolated from the Gastric Mucosa of a Kitten with Severe Gastritis.

    PubMed

    Smet, Annemieke; Van Nieuwerburgh, Filip; Ledesma, Jessica; Flahou, Bram; Deforce, Dieter; Ducatelle, Richard; Haesebrouck, Freddy

    2013-01-01

    Here we report the genome sequence of Helicobacter heilmannii sensu stricto ASB1 isolated from the gastric mucosa of a kitten with severe gastritis. Helicobacter heilmannii sensu stricto has also been associated with gastric disease in humans. Availability of this genome sequence will contribute to the identification of genes involved in the pathogen's virulence and carcinogenic properties.

  14. Genome Sequence of Helicobacter heilmannii Sensu Stricto ASB1 Isolated from the Gastric Mucosa of a Kitten with Severe Gastritis

    PubMed Central

    Van Nieuwerburgh, Filip; Ledesma, Jessica; Flahou, Bram; Deforce, Dieter; Ducatelle, Richard; Haesebrouck, Freddy

    2013-01-01

    Here we report the genome sequence of Helicobacter heilmannii sensu stricto ASB1 isolated from the gastric mucosa of a kitten with severe gastritis. Helicobacter heilmannii sensu stricto has also been associated with gastric disease in humans. Availability of this genome sequence will contribute to the identification of genes involved in the pathogen’s virulence and carcinogenic properties. PMID:23405321

  15. A new species of Daedalea (Basidiomycota) and a synopsis of core species in Daedalea sensu stricto

    Treesearch

    Daniel L. Lindner; Leif Ryvarden; Timothy J. Baroni

    2011-01-01

    Daedalea neotropica, a species with striking violet stains on the pileus and pore surface, is described from material collected in the Maya Mountains of Belize. A synopsis of Daedalea sensu stricto is provided based on morphological and DNA sequence data. Analyses indicate that at least four species should be included in ...

  16. Bread, beer and wine: yeast domestication in the Saccharomyces sensu stricto complex.

    PubMed

    Sicard, Delphine; Legras, Jean-Luc

    2011-03-01

    Yeasts of the Saccharomyces sensu stricto species complex are able to convert sugar into ethanol and CO(2) via fermentation. They have been used for thousands years by mankind for fermenting food and beverages. In the Neolithic times, fermentations were probably initiated by naturally occurring yeasts, and it is unknown when humans started to consciously add selected yeast to make beer, wine or bread. Interestingly, such human activities gave rise to the creation of new species in the Saccharomyces sensu stricto complex by interspecies hybridization or polyploidization. Within the S. cerevisiae species, they have led to the differentiation of genetically distinct groups according to the food process origin. Although the evolutionary history of wine yeast populations has been well described, the histories of other domesticated yeasts need further investigation.

  17. Effectiveness of disinfectants used in hemodialysis against both Candida orthopsilosis and C. parapsilosis sensu stricto biofilms.

    PubMed

    Pires, Regina Helena; da Silva, Julhiany de Fátima; Gomes Martins, Carlos Henrique; Fusco Almeida, Ana Marisa; Pienna Soares, Christiane; Soares Mendes-Giannini, Maria José

    2013-05-01

    Biofilms have been observed in the fluid pathways of hemodialysis machines. The impacts of four biocides used for the disinfection of hemodialysis systems were tested against Candida parapsilosis sensu stricto and Candida orthopsilosis biofilms generated by isolates obtained from a hydraulic circuit that were collected in a hemodialysis unit. Acetic acid was shown to be the most effective agent against Candida biofilms. Strategies for effective disinfection procedures used for hemodialysis systems should also seek to kill and inhibit biofilms.

  18. Habitat discrimination by gravid Anopheles gambiae sensu lato – a push-pull system

    PubMed Central

    2014-01-01

    Background The non-random distribution of anopheline larvae in natural habitats suggests that gravid females discriminate between habitats of different quality. Whilst physical and chemical cues used by Culex and Aedes vector mosquitoes for selecting an oviposition site have been extensively studied, those for Anopheles remain poorly explored. Here the habitat selection by Anopheles gambiae sensu lato (s.l.), the principal African malaria vector, was investigated when presented with a choice of two infusions made from rabbit food pellets, or soil. Methods Natural colonization and larval survival was evaluated in artificial ponds filled randomly with either infusion. Dual-choice, egg-count bioassays evaluated the responses of caged gravid females to (1) two- to six-day old infusions versus lake water; (2) autoclaved versus non-autoclaved soil infusions; and assessed (3) the olfactory memory of gravid females conditioned in pellet infusion as larvae. Results Wild Anopheles exclusively colonized ponds with soil infusion and avoided those with pellet infusion. When the individual infusions were tested in comparison with lake water, caged An. gambiae sensu stricto (s.s.) showed a dose response: females increasingly avoided the pellet infusion with increasing infusion age (six-day versus lake water: odds ratio (OR) 0.22; 95% confidence interval (CI) 0.1-0.5) and showed increasing preference to lay eggs as soil infusion age increased (six-day versus lake water: OR 2.1; 95% CI 1.4-3.3). Larvae survived in soil infusions equally well as in lake water but died in pellet infusions. Anopheles gambiae s.s. preferred to lay eggs in the non-autoclaved soil (OR 2.6; 95% CI 1.8-3.7) compared with autoclaved soil. There was no change in the avoidance of pellet infusion by individuals reared in the infusion compared with those reared in lake water. Conclusion Wild and caged An. gambiae s.l. females discriminate between potential aquatic habitats for oviposition. These choices benefit

  19. Analysis of Sporothrix schenckii sensu stricto and Sporothrix brasiliensis virulence in Galleria mellonella.

    PubMed

    Clavijo-Giraldo, Diana M; Matínez-Alvarez, José A; Lopes-Bezerra, Leila M; Ponce-Noyola, Patricia; Franco, Bernardo; Almeida, Ricardo S; Mora-Montes, Héctor M

    2016-03-01

    The study of the host-pathogen interaction is essential to understand the mechanisms underlying adhesion, colonization and tissue damage by pathogens. This is usually achieved by performing in vivo studies using small mammals, such as rats, mice and guinea pigs. Nowadays, the mouse models of systemic or subcutaneous infection are the gold standard assays to analyze the virulence of members of the Sporothrix schenckii complex. There are, however, invertebrates that have been recently used as alternative hosts to assess the virulence of both bacteria and fungi, and among them, larvae of Galleria mellonella are popular because they are easy to breed, and require non-specialized facilities to maintain the colony. Here, we assessed the use of G. mellonella larvae to test the virulence of S. schenckii sensu stricto and Sporothrix brasiliensis strains, and found that infection with yeast-like cells, but not with conidia or germlings, reproduces the virulence data generated in the mouse model of infection. Furthermore, with this insect model we could classify the virulence of some strains as low, intermediate or high, in line with the observations in the mammalian model. Therefore, G. mellonella is suitable, and a new alternative, to test virulence of both S. schenckii sensu stricto and S. brasiliensis.

  20. Four Clones of Borrelia burgdorferi Sensu Stricto Cause Invasive Infection in Humans

    PubMed Central

    Seinost, Gerald; Dykhuizen, Daniel E.; Dattwyler, Raymond J.; Golde, William T.; Dunn, John J.; Wang, Ing-Nang; Wormser, Gary P.; Schriefer, Martin E.; Luft, Benjamin J.

    1999-01-01

    Lyme disease begins at the site of a tick bite, producing a primary infection with spread of the organism to secondary sites occurring early in the course of infection. A major outer surface protein expressed by the spirochete early in infection is outer surface protein C (OspC). In Borrelia burgdorferi sensu stricto, OspC is highly variable. Based on sequence divergence, alleles of ospC can be divided into 21 major groups. To assess whether strain differences defined by ospC group are linked to invasiveness and pathogenicity, we compared the frequency distributions of major ospC groups from ticks, from the primary erythema migrans skin lesion, and from secondary sites, principally from blood and spinal fluid. The frequency distribution of ospC groups from ticks is significantly different from that from primary sites, which in turn is significantly different from that from secondary sites. The major groups A, B, I, and K had higher frequencies in the primary sites than in ticks and were the only groups found in secondary sites. We define three categories of major ospC groups: one that is common in ticks but very rarely if ever causes human disease, a second that causes only local infection at the tick bite site, and a third that causes systemic disease. The finding that all systemic B. burgdorferi sensu stricto infections are associated with four ospC groups has importance in the diagnosis, treatment, and prevention of Lyme disease. PMID:10377134

  1. Demonstration of Borrelia burgdorferi sensu stricto infection in ticks from the northeast of Mexico.

    PubMed

    Gordillo-Pérez, G; Vargas, M; Solórzano-Santos, F; Rivera, A; Polaco, O J; Alvarado, L; Muñóz, O; Torres, J

    2009-05-01

    Borrelia burgdorferisensu lato infection has been confirmed in clinical cases in the northeast of Mexico; however, the bacterium has not been identified as infecting the tick vector Ixodes, Amblyomma and Dermacentor ticks were collected from mammals and plants in northeastern Mexico and examined for Borrelia. Eighteen of 214 ticks were PCR-positive for the fla and 16S rRNA genes and 15 for the ospA gene. Southern blotting with a fla probe and sequencing of ospA genes confirmed infection with B. burgdorferi sensu stricto. These findings, together with reports of indigenous cases, fulfil the criteria that allow northeastern Mexico to be considered as a zone endemic for Lyme disease.

  2. Genetic relationship between the Echinococcus granulosus sensu stricto cysts located in lung and liver of hosts.

    PubMed

    Oudni-M'rad, Myriam; Cabaret, Jacques; M'rad, Selim; Chaâbane-Banaoues, Raja; Mekki, Mongi; Zmantar, Sofien; Nouri, Abdellatif; Mezhoud, Habib; Babba, Hamouda

    2016-10-01

    G1 genotype of Echinococcus granulosus sensu stricto is the major cause of hydatidosis in Northern Africa, Tunisia included. The genetic relationship between lung and liver localization were studied in ovine, bovine and human hydatid cysts in Tunisia. Allozyme variation and single strand conformation polymorphism were used for genetic differentiation. The first cause of genetic differentiation was the host species and the second was the localization (lung or liver). The reticulated genetic relationship between the liver or the lung human isolates and isolates from bovine lung, is indicative of recombination (sexual reproduction) or lateral genetic transfer. The idea of two specialized populations (one for the lung one for the liver) that are more or less successful according to host susceptibility is thus proposed. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. [The production of knowledge regarding gestational hypertension in the stricto sensu graduate nursing studies in Brazil].

    PubMed

    Martins, Marialda; Monticelli, Marisa; Brüggemann, Odaléa Maria; Costa, Roberta

    2012-08-01

    This documental study analyzed the Brazilian production of stricto sensu nursing graduate programs related to gestational hypertension. The data source used was the Brazilian Nursing Association Theses and Dissertations Database. The survey located 14 studies produced between 1979-2008, produced mainly in the Southeast region between 1996 and2008. The analytical process revealed a concern with the subjectivity of pregnant women and with aspects regarding nursing care. Furthermore, it showed that most studies used a qualitative methodology supported by nursing theories. The experience lived by pregnant women with hypertension is marked by negative feelings and socioeconomic problems, and is also affected by how the family is organized. The culture of pregnant women with hypertension is disregarded and they receive care in a context in which the disease is the priority. In conclusion, despite some scientific advancements, this topic has not raised the interest it deserves among nurses attending graduate study programs.

  4. Principal component analysis of MALDI TOF MS mass spectra separates M. abscessus (sensu stricto) from M. massiliense isolates.

    PubMed

    Kehrmann, Jan; Wessel, Sarah; Murali, Roshni; Hampel, Annegret; Bange, Franz-Christoph; Buer, Jan; Mosel, Frank

    2016-03-01

    The discrimination of the members of the Mycobacterium abscessus complex is of clinical interest because one of the subspecies, M. massiliense, exhibits higher rates of response to antibiotic treatment for lung infection than do the other members of that complex. M. abscessus complex contains three subspecies that are laborious to identify; therefore, a routine diagnostic tool would be worthwhile. We used principal component analysis, hierarchical cluster analysis, and single-peak analysis to examine peak lists derived from matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS) mass spectra of 50 clinical M. abscessus complex isolates, including 28 M. abscessus (sensu stricto), 19 M. massiliense, and 3 M. bolletii isolates grown in mycobacterium growth indicator tube liquid medium and prepared with a bead-based protocol. Principal component analysis but not hierarchical cluster analysis separated M. abscessus (sensu stricto) isolates and M. massiliense isolates into two clusters. Furthermore, single-peak analysis displayed 4 discriminating peaks that separated M. abscessus (sensu stricto) from M. massiliense isolates. M. bolletii isolates did not exhibit specific peaks but resembled the M. abscessus (sensu stricto) peak profile and also grouped within this principal component analysis cluster. Principal component analysis of all peak lists with the exclusion of the four discriminating peaks again separated M. abscessus (sensu stricto) from M. massiliense isolates, thus relativizing the importance of these peaks for subspecies identification. Principal component analysis of peak lists derived from MALDI TOF mass spectra is a robust and convenient method of discriminating M. massiliense isolates from the other members of the M. abscessus complex.

  5. Similarities in murine infection and immune response to Borrelia bissettii and Borrelia burgdorferi sensu stricto.

    PubMed

    Leydet, Brian F; Liang, Fang Ting

    2015-12-01

    In 1982, Borrelia burgdorferi sensu stricto (ss) was identified as the aetiological agent of Lyme disease. Since then an increasing number of Borrelia burgdorferi sensu lato (sl) species have been isolated in the United States. To date, many of these species remain understudied despite mounting evidence associating them with human illness. Borrelia bissettii is a spirochaete closely related to B. burgdorferi that has been loosely associated with human illness. Using an experimental murine infection model, we compared the infectivity and humoral immune response with a North American isolate of B. bissettii and B. burgdorferi using culture, molecular and serological methods. The original B. bissettii cultures were unable to infect immunocompetent mice, but were confirmed to be infectious after adaptation in immunodeficient animals. B. bissettii infection resulted in spirochaete burdens similar to B. burgdorferi in skin, heart and bladder whereas significantly lower burdens were observed in the joint tissues. B. bissettii induced an antibody response similar to B. burgdorferi as measured by both immunoblotting and the C6 ELISA. Additionally, this isolate of B. bissettii was sequenced on the Ion Torrent PGM, which successfully identified many genes orthologous to mammalian virulence factors described in B. burgdorferi. Similarities seen between both infections in this well-characterized murine model contribute to our understanding of the potential pathogenic nature of B. bissettii. Infection dynamics of B. bissettii, and especially the induced humoral response, are similar to B. burgdorferi, suggesting this species may contribute to the epidemiology of human borreliosis.

  6. Echinococcus granulosus sensu stricto (s.s.) from the critically endangered antelope Addax nasomaculatus in Tunisia.

    PubMed

    Boufana, Belgees; Saïd, Yousra; Dhibi, Mokhtar; Craig, Philip S; Lahmar, Samia

    2015-12-01

    Echinococcus granulosus sensu lato (s.l.) is a zoonotic disease highly endemic in Tunisia. Canids including stray and semi-stray dogs, jackals and foxes are known as definitive hosts and a wide range of ungulates have been shown to harbour the metacestode hydatid stage and may serve as intermediate hosts. Fertile hydatid cysts of Echinococcus equinus and E. granulosus sensu stricto (s.s.) were recently molecularly identified for the first time from Tunisian donkeys. E. granulosus (s.s.) was also identified from wild boars in Tunisia. Here we report the confirmation of hydatid cysts caused by E. granulosus (s.s.) in the critically endangered antelope, Addax nasomaculatus in Tunisia. DNA-based molecular analysis revealed that A.nasomaculatus was infected with E. granulosus (s.s.) which had a 100% identity with the main globally distributed E. granulosus (s.s.) (EgTu01) haplotype. Cysts of Taenia hydatigena (n=33) were also observed on the liver and in the body cavity. Due to their endangered status and their relatively small numbers, it is unlikely that hydatid infection of A. nasomaculatus will form a major contribution to the epidemiology and transmission of E. granulosus in Tunisia, but infection may result in pathology, morbidity and early mortality, and may still play a role in the perpetuation of the parasite in wildlife cycles.

  7. The optimum cut-off value to differentiate Echinococcus granulosus sensu stricto from other species of E. granulosus sensu lato using larval rostellar hook morphometry.

    PubMed

    Soriano, S V; Pierangeli, N B; Pianciola, L A; Mazzeo, M; Lazzarini, L E; Debiaggi, M F; Bergagna, H F J; Basualdo, J A

    2015-01-01

    Cystic echinococcosis caused by Echinococcus granulosus sensu lato is one of the most important helminth zoonoses in the world; it affects both humans and livestock. The disease is endemic in Argentina and highly endemic in the province of Neuquén. Considerable genetic and phenotypic variation has been demonstrated in E. granulosus, and ten different genotypes (G1-G10) have been identified using molecular tools. Echinococcus granulosus sensu lato may be considered a species complex, comprised of E. granulosus sensu stricto (G1-G3), E. equinus (G4), E. ortleppi (G5) and E. canadensis (G6-G10). In endemic areas, the characterization of cystic echinococcosis molecular epidemiology is important in order to apply adequate control strategies. A cut-off value for larval large hook total length to distinguish E. granulosus sensu stricto isolates from those produced by other species of the complex was defined for the first time. Overall, 1780 larval hooks of 36 isolates obtained from sheep (n= 11, G1), goats (n= 10, G6), cattle (n= 5, G6) and pigs (n= 10, G7) were analysed. Validation against molecular genotyping as gold standard was carried out using the receiver operating characteristic (ROC) curve analysis. The optimum cut-off value was defined as 26.5 μm. The proposed method showed high sensitivity (97.8%) and specificity (91.1%). Since in most endemic regions the molecular epidemiology of echinococcosis includes the coexistence of the widely distributed E. granulosus sensu stricto G1 strain and other species of the complex, this technique could be useful as a quick and economical tool for epidemiological and surveillance field studies, when fertile cysts are present.

  8. Molecular characterization of Echinococcus granulosus sensu stricto and Echinococcus canadensis in humans and livestock from Algeria.

    PubMed

    Zait, Houria; Kouidri, Mokhtaria; Grenouillet, Florence Elisabeth; Umhang, Gérald; Millon, Laurence; Hamrioui, Boussad; Grenouillet, Frédéric

    2016-06-01

    In Algeria, previous studies investigated genotypes of Echinococcus granulosus sensu lato in animals and identified E. granulosus sensu stricto (s.s.) genotypes G1 and G3 whereas Echinococcus canadensis genotype G6 was only reported from dromedary cysts. Molecular data on human cystic echinococcosis (CE) were limited. We implemented a large genotyping study of hydatid cysts from humans and livestock animals to specify CE's molecular epidemiology and the genetic diversity in Algeria. Fifty-four human CE cysts from patients predominantly admitted in surgical units from Mustapha Hospital, Algiers, and 16 cysts from livestock animals gathered in two geographically distinct slaughterhouses, Tiaret and Tamanrasset, were collected. Molecular characterization was performed using sequencing of two mitochondrial genes, cytochrome c oxidase subunit I (COI) and NADH dehydrogenase subunit I (NDI). In humans, G1 of E. granulosus s.s. was the main genotype (90.7 %); four samples (7.4 %) were characterized as E. granulosus s.s. G3 and one cyst as E. canadensis G6 (1.8 %). This molecular confirmation of E. canadensis G6 human infection in Algeria was observed in a Tuareg female living in a desertic area in Tamanrasset. All cysts from sheep, cattle, and goat were identified as E. granulosus s.s. G1 and the two cysts originating from dromedary as E. canadensis G6. Twenty concatenated haplotypes (COI + NDI) were characterized. Among E. granulosus s.s., one haplotype (HL1) was highly predominant in both humans and animals cysts (71.6 %). This study revealed main occurrence of E. granulosus s.s. in humans and livestock animals, with description of a predominant shared haplotype corresponding to the main worldwide observed haplotype E.granulosus s.s. G1. E. canadensis G6 was limited to South Algeria, in dromedary as well as in human.

  9. A Clonal Subpopulation of Leptospira interrogans Sensu Stricto Is the Major Cause of Leptospirosis Outbreaks in Brazil

    PubMed Central

    Pereira, M. M.; Matsuo, M. G. S.; Bauab, A. R.; Vasconcelos, S. A.; Moraes, Z. M.; Baranton, G.; Saint Girons, I.

    2000-01-01

    Leptospira is a highly diverse genus comprising many species and serogroups in Brazil as well as all over the world. However, a study by arbitrarily primed PCR of 44 leptospiral strains isolated from humans during three different outbreaks in Brazilian urban centers reveals that 43 of 44 isolates exhibit very similar fingerprints. Analysis of these isolates indicates that they belong to a clonal subpopulation of Leptospira interrogans sensu stricto. PMID:10618140

  10. In Vitro Activities of Amphotericin B, Terbinafine, and Azole Drugs against Clinical and Environmental Isolates of Aspergillus terreus Sensu Stricto

    PubMed Central

    Fernández, Mariana S.; Rojas, Florencia D.; Cattana, María E.; Sosa, María de los Ángeles; Iovannitti, Cristina A.; Giusiano, Gustavo E.

    2015-01-01

    The antifungal susceptibilities of 40 clinical and environmental isolates of A. terreus sensu stricto to amphotericin B, terbinafine, itraconazole, and voriconazole were determined in accordance with CLSI document M38-A2. All isolates had itraconazole and voriconazole MICs lower than epidemiologic cutoff values, and 5% of the isolates had amphotericin B MICs higher than epidemiologic cutoff values. Terbinafine showed the lowest MICs. No significant differences were found when MICs of clinical and environmental isolates were compared. PMID:25824228

  11. Genetic diversity and population genetic structure analysis of Echinococcus granulosus sensu stricto complex based on mitochondrial DNA signature.

    PubMed

    Sharma, Monika; Fomda, Bashir Ahmad; Mazta, Saligram; Sehgal, Rakesh; Singh, Balbir Bagicha; Malla, Nancy

    2013-01-01

    The genetic diversity and population genetics of the Echinococcus granulosus sensu stricto complex were investigated based on sequencing of mitochondrial DNA (mtDNA). Total 81 isolates of hydatid cyst collected from ungulate animals from different geographical areas of North India were identified by sequencing of cytochrome c oxidase subunit1 (coxi) gene. Three genotypes belonging to E. granulosus sensu stricto complex were identified (G1, G2 and G3 genotypes). Further the nucleotide sequences (retrieved from GenBank) for the coxi gene from seven populations of E. granulosus sensu stricto complex covering 6 continents, were compared with sequences of isolates analysed in this study. Molecular diversity indices represent overall high mitochondrial DNA diversity for these populations, but low nucleotide diversity between haplotypes. The neutrality tests were used to analyze signatures of historical demographic events. The Tajima's D test and Fu's FS test showed negative value, indicating deviations from neutrality and both suggested recent population expansion for the populations. Pairwise fixation index was significant for pairwise comparison of different populations (except between South America and East Asia, Middle East and Europe, South America and Europe, Africa and Australia), indicating genetic differentiation among populations. Based on the findings of the present study and those from earlier studies, we hypothesize that demographic expansion occurred in E. granulosus after the introduction of founder haplotype particular by anthropogenic movements.

  12. Evidence for Host-Genotype Associations of Borrelia burgdorferi Sensu Stricto.

    PubMed

    Mechai, Samir; Margos, Gabriele; Feil, Edward J; Barairo, Nicole; Lindsay, L Robbin; Michel, Pascal; Ogden, Nicholas H

    2016-01-01

    Different genotypes of the agent of Lyme disease in North America, Borrelia burgdorferi sensu stricto, show varying degrees of pathogenicity in humans. This variation in pathogenicity correlates with phylogeny and we have hypothesized that the different phylogenetic lineages in North America reflect adaptation to different host species. In this study, evidence for host species associations of B. burgdorferi genotypes was investigated using 41 B. burgdorferi-positive samples from five mammal species and 50 samples from host-seeking ticks collected during the course of field studies in four regions of Canada: Manitoba, northwestern Ontario, Quebec, and the Maritimes. The B. burgdorferi genotypes in the samples were characterized using three established molecular markers (multi-locus sequence typing [MLST], 16S-23S rrs-rrlA intergenic spacer, and outer surface protein C sequence [ospC] major groups). Correspondence analysis and generalized linear mixed effect models revealed significant associations between B. burgdorferi genotypes and host species (in particular chipmunks, and white-footed mice and deer mice), supporting the hypotheses that host adaptation contributes to the phylogenetic structure and possibly the observed variation in pathogenicity in humans.

  13. Echinococcus equinus and Echinococcus granulosus sensu stricto from the United Kingdom: genetic diversity and haplotypic variation.

    PubMed

    Boufana, Belgees; Lett, Wai San; Lahmar, Samia; Buishi, Imad; Bodell, Anthony J; Varcasia, Antonio; Casulli, Adriano; Beeching, Nicholas J; Campbell, Fiona; Terlizzo, Monica; McManus, Donald P; Craig, Philip S

    2015-02-01

    Cystic echinococcosis is endemic in Europe including the United Kingdom. However, information on the molecular epidemiology of Echinococcus spp. from the United Kingdom is limited. Echinococcus isolates from intermediate and definitive animal hosts as well as from human cystic echinococcosis cases were analysed to determine species and genotypes within these hosts. Echinococcus equinus was identified from horse hydatid isolates, cysts retrieved from captive UK mammals and copro-DNA of foxhounds and farm dogs. Echinococcus granulosus sensu stricto (s.s.) was identified from hydatid cysts of sheep and cattle as well as in DNA extracted from farm dog and foxhound faecal samples, and from four human cystic echinococcosis isolates, including the first known molecular confirmation of E. granulosus s.s. infection in a Welsh sheep farmer. Low genetic variability for E. equinus from various hosts and from different geographical locations was detected using the mitochondrial cytochrome c oxidase subunit 1 gene (cox1), indicating the presence of a dominant haplotype (EQUK01). In contrast, greater haplotypic variation was observed for E. granulosus s.s. cox1 sequences. The haplotype network showed a star-shaped network with a centrally placed main haplotype (EgUK01) that had been reported from other world regions.

  14. Climate trends in the wood anatomy of Acacia sensu stricto (Leguminosae: Mimosoideae).

    PubMed

    Warwick, Nigel W M; Hailey, Luke; Clarke, Kerri L; Gasson, Peter E

    2017-06-01

    This study investigates the structural diversity of the secondary xylem of 54 species of Acacia from four taxonomic sections collected across five climate regions along a 1200 km E-W transect from sub-tropical [approx. 1400 mm mean annual precipitation (MAP)] to arid (approx. 240 mm MAP) in New South Wales, Australia. Acacia sensu stricto ( s.s. ) is a critical group for understanding the effect of climate and phylogeny on the functional anatomy of wood. Wood samples were sectioned in transverse, tangential and radial planes for light microscopy and analysis. The wood usually has thick-walled vessels and fibres, paratracheal parenchyma and uniseriate and biseriate rays, occasionally up to four cells wide. The greater abundance of gelatinous fibres in arid and semi-arid species may have ecological significance. Prismatic crystals in chambered fibres and axial parenchyma increased in abundance in semi-arid and arid species. Whereas vessel diameter showed only a small decrease from the sub-tropical to the arid region, there was a significant 2-fold increase in vessel frequency and a consequent 3-fold decrease in the vulnerability index. Although the underlying phylogeny determines the qualitative wood structure, climate has a significant influence on the functional wood anatomy of Acacia s.s. , which is an ideal genus to study the effect of these factors.

  15. Borrelia burgdorferi sensu stricto and Borrelia afzelii: Population structure and differential pathogenicity.

    PubMed

    Jungnick, Sabrina; Margos, Gabriele; Rieger, Melissa; Dzaferovic, Eldina; Bent, Stephen J; Overzier, Evelyn; Silaghi, Cornelia; Walder, Gernot; Wex, Franziska; Koloczek, Johannes; Sing, Andreas; Fingerle, Volker

    2015-10-01

    MultiLocus sequence typing (MLST) is considered a powerful method to unveil relationships within bacterial populations and it constitutes an economical and fast alternative to whole genome sequencing. We used this method to understand whether there are differences in human pathogenicity within and between different Borrelia burgdorferi sensu lato species. Therefore, 136 strains from human patients or ticks from Europe were included in MLST analyses. The scheme employed used eight chromosomally located housekeeping genes (i.e. clpA, clpX, nifS, pepX, pyrG, recG, rplB and uvrA). We investigated Borrelia afzelii, one of the predominant species in Europe, and B. burgdorferi sensu stricto (s.s.), because it allowed comparative analysis to strains from the USA. We typed 113 patient isolates as well as 23 tick isolates. For further comparative purposes an additional 746 strains from Europe and the USA were included from the MLST website http://borrelia.mlst.net. We observed an overlap of the B. burgdorferi s.s. populations from Europe and the USA isolated from human patients while there was no overlap of the populations found in tick vectors. Further results indicate that B. afzelii was significantly less associated with disseminated infection than B. burgdorferi s.s. and that B. burgdorferi s.s. from Europe caused neuroborreliosis to a significantly greater extent than B. afzelii or B. burgdorferi s.s. in the USA. Our data suggest that there may be an evolutionary basis of differential interspecies pathogenicity in Borrelia. This was not evident within Borrelia species: we found the same sequence types in patients with disseminated or localized symptoms when the number of strains was sufficiently high. We hypothesize that the finding that B. burgdorferi s.s. in Europe is much more associated with neuroborreliosis than in the USA maybe linked to factor(s) related to the human host, the tick vector or the bacterium itself (e.g. plasmid content and structure).

  16. Genetic diversity of ospC in a local population of Borrelia burgdorferi sensu stricto.

    PubMed Central

    Wang, I N; Dykhuizen, D E; Qiu, W; Dunn, J J; Bosler, E M; Luft, B J

    1999-01-01

    The outer surface protein, OspC, is highly variable in Borrelia burgdorferi sensu stricto, the agent of Lyme disease. We have shown that even within a single population OspC is highly variable. The variation of ospA and ospC in the 40 infected deer ticks collected from a single site on Shelter Island, New York, was determined using PCR-SSCP. There is very strong apparent linkage disequilibrium between ospA and ospC alleles, even though they are located on separate plasmids. Thirteen discernible SSCP mobility classes for ospC were identified and the DNA sequence for each was determined. These sequences, combined with 40 GenBank sequences, allow us to define 19 major ospC groups. Sequences within a major ospC group are, on average, <1% different from each other, while sequences between major ospC groups are, on average, approximately 20% different. The tick sample contains 11 major ospC groups, GenBank contains 16 groups, with 8 groups found in both samples. Thus, the ospC variation within a local population is almost as great as the variation of a similar-sized sample of the entire species. The Ewens-Watterson-Slatkin test of allele frequency showed significant deviation from the neutral expectation, indicating balancing selection for these major ospC groups. The variation represented by major ospC groups needs to be considered if the OspC protein is to be used as a serodiagnostic antigen or a vaccine. PMID:9872945

  17. Physiological behaviour of gliotoxigenic Aspergillus fumigatus sensu stricto isolated from maize silage under simulated environmental conditions.

    PubMed

    Alonso, V; Vergara, L Díaz; Aminahuel, C; Pereyra, C; Pena, G; Torres, A; Dalcero, A; Cavaglieri, L

    2015-01-01

    Environmental conditions play a key role in fungal development. During the silage production process, humidity, oxygen availability and pH vary among lactic-fermentation phases and among different silage sections. The aim of this work was to study the physiological behaviour of gliotoxicogenic Aspergillus fumigatus strains isolated from maize silage under simulated natural physicochemical conditions - different water activities (a(W)), temperatures (Tº), pH and oxygen pressure - on the growth parameters (growth rate and lag phase) and gliotoxin production. The silage was made with the harvested whole maize plant that was chopped and used for trench-type silo fabrication. Water activity and pH of the silage samples were determined. Total fungal counts were performed on Dichloran Rose Bengal Chloramphenicol agar and Dichloran 18% Glycerol agar. The morphological identification of A. fumigatus was performed with different culture media and at different growth temperature to observe microscopic and macroscopic characteristics. Gliotoxin production by A. fumigatus was determined by HPLC. All strains isolated were morphologically identified as A. fumigatus. Two A. fumigatus strains isolated from the silage samples were selected for the ecophysiological study (A. fumigatus sensu stricto RC031 and RC032). The results of this investigation showed that the fungus grows in the simulated natural physicochemical conditions of corn silage and produces gliotoxin. The study of the physiological behaviour of gliotoxigenic A. fumigatus under simulated environmental conditions allowed its behaviour to be predicted in silage and this will in future enable appropriate control strategies to be developed to prevent the spread of this fungus and toxin production that leads to impairment and reduced quality of silage.

  18. Anisakis simplex sensu stricto and Anisakis pegreffii: biological characteristics and pathogenetic potential in human anisakiasis.

    PubMed

    Arizono, Naoki; Yamada, Minoru; Tegoshi, Tatsuya; Yoshikawa, Masahide

    2012-06-01

    Anisakiasis is one of the most common fishborne helminthic diseases in Japan, which is contracted by ingesting the larvae of the nematode Anisakis spp. carried by marine fish. Anisakis simplex sensu stricto (s.s.) and A. pegreffii are the dominant species in fish caught offshore Japan. The present study aimed to identify the anisakid species infecting Japanese patients and determine whether there is any difference in the pathogenetic potential of A. simplex (s.s.) and A. pegreffii. In total, 41 and 301 Anisakis larvae were isolated from Japanese patients and chub mackerel (Scomber japonicus), respectively; these were subjected to molecular identification using polymerase chain reaction targeted at a ribosomal DNA internal transcribed spacer region. Chub mackerel larvae were further examined for survival in artificial gastric juice (pH 1.8) for 7 days and for invasiveness on 0.75% solid agar over a 24-h interval. All clinical isolates, including those of asymptomatic, acute, and chronic infections as well as those from the stomach, small intestine, colon, and stool, were identified as A. simplex (s.s.). Chub mackerel harbored A. simplex (s.s.) and A. pegreffii larvae, together with a few larvae of other anisakid species. A. simplex (s.s.) larvae from chub mackerel tolerated the artificial gastric juice better than A. pegreffii, with 50% mortality in 2.6 and 1.4 days, respectively. In addition, A. simplex (s.s.) penetrated the agar at significantly higher rates than A. pegreffii. These results show that A. simplex (s.s.) larvae have the potential to survive acidic gastric juice to some extent and penetrate the stomach, small intestine, or colon in infected humans.

  19. Physiological and genetic stability of hybrids of industrial wine yeasts Saccharomyces sensu stricto complex.

    PubMed

    Kunicka-Styczyńska, A; Rajkowska, K

    2011-06-01

    The aim of this study was to examine the physiological and genetic stability of hybrids of industrial wine yeasts Saccharomyces sensu stricto complex subjected to acidic stress during fermentation. Laboratory-constructed yeast hybrids, one intraspecific Saccharomyces cerevisiae × S. cerevisiae and three interspecific S. cerevisiae × Saccharomyces bayanus, were subcultured in aerobic or anaerobic conditions in media with or without l-malic acid. Changes in the biochemical profiles, karyotypes and mitochondrial DNA profiles of the segregates were assessed after 50-190 generations. All yeast segregates showed a tendency to increase the range of the tested compounds utilized as sole carbon sources. Interspecific hybrids were alloaneuploid and their genomes tended to undergo extensive rearrangement especially during fermentation. The karyotypes of segregates lost up to four and appearance up to five bands were recorded. The changes in their mtDNA patterns were even broader reaching 12 missing and six additional bands. These hybrids acquired the ability to sporulate and significantly changed their biochemical profiles. The alloaneuploid intraspecific S. cerevisiae hybrid was characterized by high genetic stability despite the phenotypic changes. L-malic acid was not found to affect the extent of genomic changes of the hybrids, which suggests that their demalication ability is combined with resistance to acidic stress. The results reveal the plasticity and extent of changes of chromosomal and mitochondrial DNA of interspecific hybrids of industrial wine yeast especially under anaerobiosis. They imply that karyotyping and restriction analysis of mitochondrial DNA make it possible to quickly assess the genetic stability of genetically modified industrial wine yeasts but may not be applied as the only method for their identification and discrimination. Laboratory-constructed interspecific hybrids of industrial strains may provide a model for studying the adaptive evolution

  20. Detection of Borrelia burgdorferi sensu stricto and Borrelia garinii DNAs in patient with Hyperkeratosis lenticularis perstans (Flegel disease).

    PubMed

    Schwarzova, Katarina; Kozub, Peter; Szep, Zoltan; Golovchenko, Marina; Rudenko, Natasha

    2016-09-01

    Determination of the causative agent of erythema-like skin lesions in case of nonspecific superficial perivascular dermatitis was supported by histological examination and led to the latter diagnosis of Hyperkeratosis lenticularis perstans (Flegel disease) in patient. The presence of antibodies against Borrelia burgdorferi in patient serum was confirmed by a routine ELISA method and verified by Western blot technique. Skin biopsy and blood specimens were analyzed by PCR and multilocus sequence analysis (MLSA). Western blot method revealed IgG antibody response against two specific antigens, 17 and 83 kDa proteins. The recombinant test detected IgG antibody response against p100 and p41 antigens. The sequence analysis of amplicons from the selected genomic loci obtained from skin biopsy and serum samples revealed the presence of two species from B. burgdorferi sensu lato complex as a co-infection in this patient-B. burgdorferi sensu stricto (s.s.) and Borrelia garinii.

  1. Discrimination between E. granulosus sensu stricto, E. multilocularis and E. shiquicus Using a Multiplex PCR Assay

    PubMed Central

    Li, Li; Yan, Hong-Bin; Blair, David; Lei, Meng-Tong; Cai, Jin-Zhong; Fan, Yan-Lei; Li, Jian-Qiu; Fu, Bao-Quan; Yang, Yu-Rong; McManus, Donald P.; Jia, Wan-Zhong

    2015-01-01

    Background Infections of Echinococcus granulosus sensu stricto (s.s), E. multilocularis and E. shiquicus are commonly found co-endemic on the Qinghai-Tibet plateau, China, and an efficient tool is needed to facilitate the detection of infected hosts and for species identification. Methodology/Principal Findings A single-tube multiplex PCR assay was established to differentiate the Echinococcus species responsible for infections in intermediate and definitive hosts. Primers specific for E. granulosus, E. multilocularis and E. shiquicus were designed based on sequences of the mitochondrial NADH dehydrogenase subunit 1 (nad1), NADH dehydrogenase subunit 5 (nad5) and cytochrome c oxidase subunit 1 (cox1) genes, respectively. This multiplex PCR accurately detected Echinococcus DNA without generating nonspecific reaction products. PCR products were of the expected sizes of 219 (nad1), 584 (nad5) and 471 (cox1) bp. Furthermore, the multiplex PCR enabled diagnosis of multiple infections using DNA of protoscoleces and copro-DNA extracted from fecal samples of canine hosts. Specificity of the multiplex PCR was 100% when evaluated using DNA isolated from other cestodes. Sensitivity thresholds were determined for DNA from protoscoleces and from worm eggs, and were calculated as 20 pg of DNA for E. granulosus and E. shiquicus, 10 pg of DNA for E. multilocularis, 2 eggs for E. granulosus, and 1 egg for E. multilocularis. Positive results with copro-DNA could be obtained at day 17 and day 26 after experimental infection of dogs with larval E. multilocularis and E. granulosus, respectively. Conclusions/Significance The multiplex PCR developed in this study is an efficient tool for discriminating E. granulosus, E. multilocularis and E. shiquicus from each other and from other taeniid cestodes. It can be used for the detection of canids infected with E. granulosus s.s. and E. multilocularis using feces collected from these definitive hosts. It can also be used for the identification

  2. Sphaerospora sensu stricto: taxonomy, diversity and evolution of a unique lineage of myxosporeans (Myxozoa).

    PubMed

    Bartošová, Pavla; Fiala, Ivan; Jirků, Miloslav; Cinková, Martina; Caffara, Monica; Fioravanti, Maria Letizia; Atkinson, Stephen Douglas; Bartholomew, Jerri Lee; Holzer, Astrid Sibylle

    2013-07-01

    Myxosporeans (Myxozoa) are eukaryotic parasites, primarily of fish, whose classification is in a state of flux as taxonomists attempt to synthesize the traditional morphology-based system with emerging DNA sequence-based phylogenies. The genus Sphaerospora Thélohan, 1892, which includes pathogenic species that cause significant impacts on fisheries and aquaculture, is one of the most polyphyletic taxa and exemplifies the current challenges facing myxozoan taxonomists. The type species, S. elegans, clusters within the Sphaerospora sensu stricto clade, members of which share similar tissue tropism and long insertions in their variable rRNA gene regions. However, other morphologically similar sphaerosporids lie in different branches of myxozoan phylogenetic trees. Herein, we significantly extend taxonomic sampling of sphaerosporids with SSU+LSU rDNA and EF-2 sequence data for 12 taxa including three representatives of the morphologically similar genus Polysporoplasma Sitjà-Bobadilla et Álvarez-Pellitero, 1995. These taxa were sampled from different vertebrate host groups, biogeographic realms and environments. Our phylogenetic analyses and statistical tests of single and concatenated datasets revealed Sphaerospora s. s. as a strongly supported monophyletic lineage, that clustered sister to the whole myxosporean clade (freshwater+marine lineages). Generally, Sphaerospora s. s. rDNA sequences (up to 3.7 kb) are the longest of all myxozoans and indeed metazoans. The sphaerosporid clade has two lineages, which have specific morphological, biological and sequence traits. Lineage A taxa (marine Sphaerospora spp.) have a single binucleate sporoplasm and shorter AT-rich rDNA inserts. Lineage B taxa (freshwater/brackish Sphaerospora spp.+marine/brackish Polysporoplasma spp.) have 2-12 uninucleate sporoplasms and longer GC-rich rDNA inserts. Lineage B has four subclades that correlate with host group and habitat; all Polysporoplasma species, including the type species

  3. First molecular evidence of the simultaneous human infection with two species of Echinococcus granulosus sensu lato: Echinococcus granulosus sensu stricto and Echinococcus canadensis.

    PubMed

    Oudni-M'rad, Myriam; M'rad, Selim; Ksia, Amine; Lamiri, Rachida; Mekki, Mongi; Nouri, Abdellatif; Mezhoud, Habib; Babba, Hamouda

    2016-03-01

    Cystic echinococcosis is a widespread zoonotic parasitic disease especially in Tunisia which is one of the most endemic countries in the Mediterranean area. The etiological agent, Echinococcus granulosus sensu lato, implies dogs and other canids as definitive hosts and different herbivore species as intermediate hosts. Human contamination occurs during the consumption of parasite eggs passed in the environment through canid feces. Hydatid cysts coming from a child operated for multiple echinococcosis were collected and analyzed in order to genotype and to obtain some epidemiological molecular information. Three targets, ribosomal DNA ITS1 fragment, NADH dehydrogenase subunit 1 (nad1), and mitochondrial cytochrome c oxydase subunit 1 (CO1) genes, were amplified and analyzed by RFLP and sequencing approach. This study presents the first worldwide report in human of a simultaneous infection with Echinococcus granulosus sensu stricto (genotype G1) and Echinococcus canadensis (genotype G6) species. This is also the first report of the presence of E. canadensis in the Tunisian population which argues in favor of a greater importance of this species in human infestation in Tunisia than previously believed.

  4. Differences in Genotype, Clinical Features, and Inflammatory Potential of Borrelia burgdorferi sensu stricto Strains from Europe and the United States.

    PubMed

    Cerar, Tjasa; Strle, Franc; Stupica, Dasa; Ruzic-Sabljic, Eva; McHugh, Gail; Steere, Allen C; Strle, Klemen

    2016-05-01

    Borrelia burgdorferi sensu stricto isolates from patients with erythema migrans in Europe and the United States were compared by genotype, clinical features of infection, and inflammatory potential. Analysis of outer surface protein C and multilocus sequence typing showed that strains from these 2 regions represent distinct genotypes. Clinical features of infection with B. burgdorferi in Slovenia were similar to infection with B. afzelii or B. garinii, the other 2 Borrelia spp. that cause disease in Europe, whereas B. burgdorferi strains from the United States were associated with more severe disease. Moreover, B. burgdorferi strains from the United States induced peripheral blood mononuclear cells to secrete higher levels of cytokines and chemokines associated with innate and Th1-adaptive immune responses, whereas strains from Europe induced greater Th17-associated responses. Thus, strains of the same B. burgdorferi species from Europe and the United States represent distinct clonal lineages that vary in virulence and inflammatory potential.

  5. Polyphasic taxonomy of the basidiomycetous yeast genus Rhodotorula: Rh. glutinis sensu stricto and Rh. dairenensis comb. nov.

    PubMed

    Gadanho, Mário; Sampaio, José Paulo

    2002-03-01

    The phenotypic and genetic heterogeneity of the basidiomycetous yeast species Rhodotorula glutinis was investigated in a group of 109 isolates. A polyphasic taxonomic approach was followed which included PCR fingerprinting, determination of sexual compatibility, 26S and ITS rDNA sequence analysis, DNA-DNA reassociation experiments and reassessment of micromorphological and physiological attributes. The relationships with species of the teleomorphic genus Rhodosporidium were studied and isolates previously identified as Rh. glutinis were found to belong to Rhodosporidium babjevae, Rhodosporidium diobovatum and Rhodosporidium sphaerocarpum. Other isolates included in the study were found to belong to Rh. glutinis var. dairenensis, which is elevated to the species level, or to undescribed species. The concept of Rh. glutinis sensu stricto is proposed due to the close phenetic and phylogenetic proximity detected for Rh. glutinis, Rhodotorula graminis and R. babjevae.

  6. Evaluation of capacity to detect ability to form biofilm in Candida parapsilosis sensu stricto strains by MALDI-TOF MS.

    PubMed

    Mlynáriková, Katarína; Šedo, Ondrej; Růžička, Filip; Zdráhal, Zbyněk; Holá, Veronika; Mahelová, Martina

    2016-11-01

    Matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is, currently, used as a rapid and reliable tool in microbial diagnostics. The discriminatory power of the method extends its applicability also beyond species level. This study examined the possibility to use MALDI-TOF MS to differentiate between Candida parapsilosis sensu stricto biofilm-positive (n = 12) and biofilm-negative (n = 9) strains. The results indicated a grouping trend within MALDI-TOF mass spectra belonging to each of the tested groups. However, these trends were eclipsed by mass spectral variations resulting from limited repeatability of the method, making its application for the selected purpose impossible. Improvement in the discriminatory power of the method was not obtained neither by using different matrices (α-cyano-4-hydroxycinnamic acid, ferulic acid, 5-chloro-2-mercaptobenzothionazole) for MALDI-TOF MS analysis nor by testing different culture conditions (cultivation length, culture media).

  7. Dectin-1 expression by macrophages and related antifungal mechanisms in a murine model of Sporothrix schenckii sensu stricto systemic infection.

    PubMed

    Jellmayer, Juliana Aparecida; Ferreira, Lucas Souza; Manente, Francine Alessandra; Gonçalves, Amanda Costa; Polesi, Marisa Campos; Batista-Duharte, Alexander; Carlos, Iracilda Zeppone

    2017-09-01

    The available information about the role of Dectin-1 in sporotrichosis is scarce. Hence, we aimed to assess Dectin-1 expression by macrophages and the activation of some related antifungal mechanisms during the Sporothrix schenckii sensu stricto infection as a first attempt to elucidate the role of this receptor in sporotrichosis. Balb/c mice were intraperitoneally infected with S. schenckii sensu stricto yeast ATCC 16345 and euthanized on days 5, 10 and 15 post-infection, when the following parameters were evaluated: fungal burden in spleen, Dectin-1 expression and nitric oxide (NO) production by peritoneal macrophages, as well as IL-1β, TNF-α and IL-10 ex vivo secretion by these same cells. Peritoneal macrophages were ex vivo challenged with either the alkali-insoluble fraction (F1) extracted from the S. schenckii cell wall, a commercially available purified β-1,3-glucan or whole heat-killed S. schenckii yeasts (HKss). Additionally, a Dectin-1 antibody-mediated blockade assay was performed on day 10 post-infection to assess the participation of this receptor in cytokine secretion. Our results showed that Dectin-1 expression by peritoneal macrophages was augmented on days 10 and 15 post-infection alongside elevated NO production and ex vivo secretion of IL-10, TNF-α and IL-1β. The antibody-mediated blockade of Dectin-1 inhibited cytokine production in both infected and non-infected mice, mainly after β-1,3-glucan stimulation. Our results suggest a role for Dectin-1 in triggering the immune response during S. schenckii infection. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Reprint of "Echinococcus granulosus sensu stricto (s.s.) from the critically endangered antelope Addax nasomaculatus in Tunisia".

    PubMed

    Boufana, Belgees; Saïd, Yousra; Dhibi, Mokhtar; Craig, Philip S; Lahmar, Samia

    2017-01-01

    Echinococcus granulosus sensu lato (s.l.) is a zoonotic disease highly endemic in Tunisia. Canids including stray and semi-stray dogs, jackals and foxes are known as definitive hosts and a wide range of ungulates have been shown to harbour the metacestode hydatid stage and may serve as intermediate hosts. Fertile hydatid cysts of Echinococcus equinus and E. granulosus sensu stricto (s.s.) were recently molecularly identified for the first time from Tunisian donkeys. E. granulosus (s.s.) was also identified from wild boars in Tunisia. Here we report the confirmation of hydatid cysts caused by E. granulosus (s.s.) in the critically endangered antelope, Addax nasomaculatus in Tunisia. DNA-based molecular analysis revealed that A. nasomaculatus was infected with E. granulosus (s.s.) which had a 100% identity with the main globally distributed E. granulosus (s.s.) (EgTu01) haplotype. Cysts of Taenia hydatigena (n=33) were also observed on the liver and in the body cavity. Due to their endangered status and their relatively small numbers, it is unlikely that hydatid infection of A. nasomaculatus will form a major contribution to the epidemiology and transmission of E. granulosus in Tunisia, but infection may result in pathology, morbidity and early mortality, and may still play a role in the perpetuation of the parasite in wildlife cycles.

  9. Proteomic profiling and characterization of differential allergens in the nematodes Anisakis simplex sensu stricto and A. pegreffii.

    PubMed

    Arcos, Susana C; Ciordia, Sergio; Roberston, Lee; Zapico, Inés; Jiménez-Ruiz, Yolanda; Gonzalez-Muñoz, Miguel; Moneo, Ignacio; Carballeda-Sangiao, Noelia; Rodriguez-Mahillo, Ana; Albar, Juan P; Navas, Alfonso

    2014-06-01

    The parasite species complex Anisakis simplex sensu lato (Anisakis simplex sensu stricto; (A. simplex s.s.), A. pegreffii, A. simplex C) is the main cause of severe anisakiasis (allergy) worldwide and is now an important health matter. In this study, the relationship of this Anisakis species complex and their allergenic capacities is assessed by studying the differences between the two most frequent species (A. simplex s.s., A. pegreffii) and their hybrid haplotype by studying active L3 larvae parasiting Merluccius merluccius. They were compared by 2D gel electrophoresis and parallel Western blot (2DE gels were hybridized with pools of sera from Anisakis allergenic patients). Unambiguous spot differences were detected and protein assignation was made by MALDI-TOF/TOF analysis or de novo sequencing. Seventy-five gel spots were detected and the corresponding proteins were identified. Differentially expressed proteins for A. simplex s.s., A. pegreffii, and their hybrid are described and results are statistically supported. Twenty-eight different allergenic proteins are classified according to different families belonging to different biological functions. These proteins are described for the first time as antigenic and potentially new allergens in Anisakis. Comparative proteomic analyses of allergenic capacities are useful for diagnosis, epidemiological surveys, and clinical research. All MS data have been deposited in the ProteomeXchange with identifier PXD000662 (http://proteomecentral.proteomexchange.org/dataset/PXD000662). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Comparison of Growth of Borrelia afzelii, Borrelia garinii, and Borrelia burgdorferi Sensu Stricto at Five Different Temperatures.

    PubMed

    Veinović, Gorana; Ružić-Sabljić, Eva; Strle, Franc; Cerar, Tjaša

    2016-01-01

    Lyme borreliosis is caused by the spirochete Borrelia burgdorferi sensu lato, a fastidious bacterium that replicates slowly and requires special conditions to grow in the laboratory. Borrelia isolation from clinical material is a golden standard for microbiological diagnosis of borrelial infection. Important factors that affect in vitro borrelia growth are temperature of incubation and number of borrelia cells in the sample. The aim of the study was to assess the influence of temperature on borrelia growth and survival by evaluation and comparison of growth of 31 different borrelia strains at five different temperatures and to determine the influence of different inoculums on borrelia growth at different temperatures. Borreliae were cultured in the MKP medium; the initial and final number of spirochetes was determined by dark field microscopy using Neubauer counting chamber. The growth of borrelia was defined as final number of cells/mL after three days of incubation. For all three Borrelia species, the best growth was found at 33°C, followed by 37, 28, and 23°C, while no growth was detected at 4°C (P<0.05). The growth of B. afzelii species was weaker in comparison to the other two species at 23, 28, 33 and 37°C (P<0.05), respectively. There was no statistically significant difference between the growth of B. garinii and B. burgdorferi sensu stricto at 28, 33, and 37°C (P>0.05), respectively. Inoculum had statistically significant influence on growth of all three Borrelia species at all tested temperatures except at 4°C.

  11. Trans-Atlantic exchanges have shaped the population structure of the Lyme disease agent Borrelia burgdorferi sensu stricto

    PubMed Central

    Castillo-Ramírez, S.; Fingerle, V.; Jungnick, S.; Straubinger, R. K.; Krebs, S.; Blum, H.; Meinel, D. M.; Hofmann, H.; Guertler, P.; Sing, A.; Margos, G.

    2016-01-01

    The origin and population structure of Borrelia burgdorferi sensu stricto (s.s.), the agent of Lyme disease, remain obscure. This tick-transmitted bacterial species occurs in both North America and Europe. We sequenced 17 European isolates (representing the most frequently found sequence types in Europe) and compared these with 17 North American strains. We show that trans-Atlantic exchanges have occurred in the evolutionary history of this species and that a European origin of B. burgdorferi s.s. is marginally more likely than a USA origin. The data further suggest that some European human patients may have acquired their infection in North America. We found three distinct genetically differentiated groups: i) the outgroup species Borrelia bissettii, ii) two divergent strains from Europe, and iii) a group composed of strains from both the USA and Europe. Phylogenetic analysis indicated that different genotypes were likely to have been introduced several times into the same area. Our results demonstrate that irrespective of whether B. burgdorferi s.s. originated in Europe or the USA, later trans-Atlantic exchange(s) have occurred and have shaped the population structure of this genospecies. This study clearly shows the utility of next generation sequencing to obtain a better understanding of the phylogeography of this bacterial species. PMID:26955886

  12. Entomopathogens of Amazonian stick insects and locusts are members of the Beauveria species complex (Cordyceps sensu stricto).

    PubMed

    Sanjuan, Tatiana; Tabima, Javier; Restrepo, Silvia; Læssøe, Thomas; Spatafora, Joseph W; Franco-Molano, Ana Esperanza

    2014-01-01

    In the Amazon the only described species of Cordyceps sensu stricto (Hypocreales, Cordycipitaceae) that parasitize insects of Orthopterida (orders Orthoptera and Phasmida) are Cordyceps locustiphila and C. uleana. However, the type specimens for both taxa have been lost and the concepts of these species are uncertain. To achieve a more comprehensive understanding of the systematics of these species, collections of Cordyceps from the Amazon regions of Colombia, Ecuador and Guyana were subjected to morphological, ecological and molecular phylogenetic studies. Phylogenetic analyses were conducted on partial sequences of SSU, LSU, TEF, RPB1 and RPB2 nuclear loci. Two new species are proposed including C. diapheromeriphila, a parasite of Phasmida, and C. acridophila, a parasite of the superfamily Acridomorpha (Orthoptera), which is broadly distributed across the Amazon. For C. locustiphila a lectotypification and an epitypification are made. Cordyceps locustiphila is host specific with Colpolopha (Acridomorpha: Romaleidae), and its distribution coincides with that of its host. The phylogenetic placement of these three species was resolved with strong support in the Beauveria clade of Cordyceps s. str. (Cordycipitaceae). This relationship and the morphological similarity of their yellow stromata with known teleomorphs of the clade, suggest that the holomorphs of these species may include Beauveria or Beauveria-like anamorphs. The varying host specificity of the beauverioid Cordyceps species suggest the potential importance of identifying the natural host taxon before future consideration of strains for use in biological control of pest locusts.

  13. A population study of killer viruses reveals different evolutionary histories of two closely related Saccharomyces sensu stricto yeasts.

    PubMed

    Chang, Shang-Lin; Leu, Jun-Yi; Chang, Tien-Hsien

    2015-08-01

    Microbes have evolved ways of interference competition to gain advantage over their ecological competitors. The use of secreted killer toxins by yeast cells through acquiring double-stranded RNA viruses is one such prominent example. Although the killer behaviour has been well studied in laboratory yeast strains, our knowledge regarding how killer viruses are spread and maintained in nature and how yeast cells co-evolve with viruses remains limited. We investigated these issues using a panel of 81 yeast populations belonging to three Saccharomyces sensu stricto species isolated from diverse ecological niches and geographic locations. We found that killer strains are rare among all three species. In contrast, killer toxin resistance is widespread in Saccharomyces paradoxus populations, but not in Saccharomyces cerevisiae or Saccharomyces eubayanus populations. Genetic analyses revealed that toxin resistance in S. paradoxus is often caused by dominant alleles that have independently evolved in different populations. Molecular typing identified one M28 and two types of M1 killer viruses in those killer strains. We further showed that killer viruses of the same type could lead to distinct killer phenotypes under different host backgrounds, suggesting co-evolution between the viruses and hosts in different populations. Taken together, our data suggest that killer viruses vary in their evolutionary histories even within closely related yeast species.

  14. Geographical distribution of Amblyomma cajennense (sensu lato) ticks (Parasitiformes: Ixodidae) in Brazil, with description of the nymph of A. cajennense (sensu stricto).

    PubMed

    Martins, Thiago F; Barbieri, Amália R M; Costa, Francisco B; Terassini, Flávio A; Camargo, Luís M A; Peterka, Cássio R L; de C Pacheco, Richard; Dias, Ricardo A; Nunes, Pablo H; Marcili, Arlei; Scofield, Alessandra; Campos, Artur K; Horta, Mauricio C; Guilloux, Aline G A; Benatti, Hector R; Ramirez, Diego G; Barros-Battesti, Darci M; Labruna, Marcelo B

    2016-03-31

    Until recently, Amblyomma cajennense (Fabricius, 1787) was considered to represent a single tick species in the New World. Recent studies have split this taxon into six species. While the A. cajennense species complex or A. cajennense (sensu lato) (s.l.) is currently represented by two species in Brazil, A. cajennense (sensu stricto) (s.s.) and Amblyomma sculptum Berlese, 1888, their geographical distribution is poorly known. The distribution of the A. cajennense (s.l.) in Brazil was determined by morphological examination of all lots of A. cajennense (s.l.) in two large tick collections of Brazil, and by collecting new material during three field expeditions in the possible transition areas between the distribution ranges of A. cajennense (s.s.) and A. sculptum. Phylogenetic analysis inferred from the ITS2 rRNA gene was used to validate morphological results. Morphological description of the nymphal stage of A. cajennense (s.s.) is provided based on laboratory-reared specimens. From the tick collections, a total 12,512 adult ticks were examined and identified as 312 A. cajennense (s.s.), 6,252 A. sculptum and 5,948 A. cajennense (s.l.). A total of 1,746 ticks from 77 localities were collected during field expeditions, and were identified as 249 A. cajennense (s.s.), 443 A. sculptum, and 1,054 A. cajennense (s.l.) [these A. cajennense (s.l.) ticks were considered to be males of either A. cajennense (s.s.) or A. sculptum]. At least 23 localities contained the presence of both A. cajennense (s.s.) and A. sculptum in sympatry. DNA sequences of the ITS2 gene of 50 ticks from 30 localities confirmed the results of the morphological analyses. The nymph of A. cajennense (s.s.) is morphologically very similar to A. sculptum. Our results confirmed that A. cajennense (s.l.) is currently represented in Brazil by only two species, A. cajennense (s.s.) and A. sculptum. While these species have distinct distribution areas in the country, they are found in sympatry in some

  15. Loxocorone, a new genus of the family loxosomatidae (Entoprocta: Solitaria), with descriptions of two new Loxomitra (sensu stricto) and a new Loxocorone from Okinawa, the Ryukyu Archipelago, Japan.

    PubMed

    Iseto, Tohru

    2002-03-01

    The type species of Loxomitra Nielsen, 1964, L. kefersteinii (Claparède, 1867), has following characters: A) the buds have a pair of terminal wings at the base of the stalk, and B) the liberated buds crawl on the substratum by attaching the two terminal wings to the substratum and twisting the whole body. By contrast, some other members of the genus have following characters: A') the buds lack the terminal wings but have a foot with foot groove, and B') the liberated buds glide over the substratum using the foot with foot groove. I thus propose to divide Loxomitra (sensu lato) into two genera- Loxomitra (sensu stricto) characterized by A) and B), and Loxocorone gen. nov. by A') and B'). I also describe two new Loxomitra (sensu stricto), L. mizugamaensis sp. nov., and L. tetraorganon sp. nov., and one new Loxocorone, L. allax sp. nov. from the Ryukyu Archipelago, Japan. All of the currently recognized species of the Loxomitra (sensu lato) are reviewed to specify their generic allocations in response to the above change.

  16. Odorant-Binding Proteins of the Malaria Mosquito Anopheles funestus sensu stricto

    PubMed Central

    Xu, Wei; Cornel, Anthony J.; Leal, Walter S.

    2010-01-01

    Background The mosquito Anopheles funestus is one of the major malaria vector species in sub-Saharan Africa. Olfaction is essential in guiding mosquito behaviors. Odorant-binding proteins (OBPs) are highly expressed in insect olfactory tissues and involved in the first step of odorant reception. An improved understanding of the function of malaria mosquito OBPs may contribute to identifying new attractants/repellents and assist in the development of more efficient and environmentally friendly mosquito controlling strategies. Methodology In this study, a large screening of over 50 ecologically significant odorant compounds led to the identification of 12 ligands that elicit significant electroantennographic (EAG) responses from An. funestus female antennae. To compare the absolute efficiency/potency of these chemicals, corrections were made for differences in volatility by determining the exact amount in a stimulus puff. Fourteen AfunOBP genes were cloned and their expression patterns were analyzed. AfunOBP1, 3, 7, 20 and 66 showed olfactory tissue specificity by reverse transcriptase PCR (RT-PCR). Quantitative real-time PCR (qRT-PCR) analysis showed that among olfactory-specific OBPs, AfunOBP1 and 3 are the most enriched OBPs in female antennae. Binding assay experiments showed that at pH 7, AfunOBP1 significantly binds to 2-undecanone, nonyl acetate, octyl acetate and 1-octen-3-ol but AfunOBP3, which shares 68% identify with AfunOBP1 at amino acid level, showed nearly no binding activity to the selected 12 EAG-active odorant compounds. Conclusion This work presents for the first time a study on the odorants and OBPs of the malaria vector mosquito An. funestus, which may provide insight into the An. funestus olfactory research, assist in a comparative study between major malaria mosquitoes An. gambiae and An. funestus olfactory system, and help developing new mosquito control strategies to reduce malaria transmission. PMID:21042539

  17. New mitogenome and nuclear evidence on the phylogeny and taxonomy of the highly zoonotic tapeworm Echinococcus granulosus sensu stricto.

    PubMed

    Kinkar, Liina; Laurimäe, Teivi; Sharbatkhori, Mitra; Mirhendi, Hossein; Kia, Eshrat Beigom; Ponce-Gordo, Francisco; Andresiuk, Vanessa; Simsek, Sami; Lavikainen, Antti; Irshadullah, Malik; Umhang, Gérald; Oudni-M'rad, Myriam; Acosta-Jamett, Gerardo; Rehbein, Steffen; Saarma, Urmas

    2017-08-01

    Cystic echinococcosis, a zoonotic disease caused by Echinococcus granulosus sensu lato (s. l.), is a significant global public health concern. Echinococcus granulosus s. l. is currently divided into numerous genotypes (G1-G8 and G10) of which G1-G3 are the most frequently implicated genotypes in human infections. Although it has been suggested that G1-G3 could be regarded as a distinct species E. granulosus sensu stricto (s. s.), the evidence to support this is inconclusive. Most importantly, data from nuclear DNA that provide means to investigate the exchange of genetic material between G1-G3 is lacking as none of the published nuclear DNA studies have explicitly included G2 or G3. Moreover, the commonly used relatively short mtDNA sequences, including the complete cox1 gene, have not allowed unequivocal differentiation of genotypes G1-G3. Therefore, significantly longer mtDNA sequences are required to distinguish these genotypes with confidence. The main aim of this study was to evaluate the phylogenetic relations and taxonomy of genotypes G1-G3 using sequences of nearly complete mitogenomes (11,443bp) and three nuclear loci (2984bp). A total of 23 G1-G3 samples were analysed, originating from 5 intermediate host species in 10 countries. The mtDNA data demonstrate that genotypes G1 and G3 are distinct mitochondrial genotypes (separated by 37 mutations), whereas G2 is not a separate genotype or even a monophyletic cluster, but belongs to G3. Nuclear data revealed no genetic separation of G1 and G3, suggesting that these genotypes form a single species due to ongoing gene flow. We conclude that: (a) in the taxonomic sense, genotypes G1 and G3 can be treated as a single species E. granulosus s. s.; (b) genotypes G1 and G3 should be regarded as distinct genotypes only in the context of mitochondrial data; (c) we recommend excluding G2 from the genotype list. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Molecular evidence for bicontinental hybridogenous genomic constitution in Lepidium sensu stricto (Brassicaceae) species from Australia and New Zealand.

    PubMed

    Mummenhoff, Klaus; Linder, Peter; Friesen, Nikolai; Bowman, John L; Lee, Ji-Young; Franzke, Andreas

    2004-02-01

    Lepidium sensu stricto (s.s.) (Brassicaceae) (ca. 150 species) is distributed worldwide with endemic species on every continent. It is represented in Australia and New Zealand by 19 and seven native species, respectively. In the present study we used a nuclear ribosomal internal transcribed spacer (ITS) phylogeny in comparison with a cpDNA phylogeny to unravel the origin of Australian/New Zealand species. Although phylogenetic relationships within Lepidium s.s. were not fully resolved, the cpDNA data were in agreement with a Californian origin of Lepidium species from Australia/New Zealand. Strongly conflicting signals between the cp- and nuclear DNA phylogenetic analysis clearly indicated hybridogenous genomic constitution of Australian Lepidium s.s. species: All 18 studied Australian/New Zealand Lepidium s.s. species examined shared a Californian cpDNA type. While eleven Australian/New Zealand species appeared to harbor a Californian ITS type, a group of seven species shared a South African ITS type. This pattern is most likely explained by two trans-oceanic dispersals of Lepidium from California and Africa to Australia/New Zealand and subsequent hybridization followed by homogenization of the ribosomal DNA either to the Californian or South African ITS type in the two different lineages. Calibration of our molecular trees indicates a Pliocene/Pleistocene origin of Lepidium in Australia/New Zealand. Low levels of cpDNA and ITS sequence divergence and unresolved topologies within Australian/New Zealand species suggest a rapid and recent radiation of Lepidium after the hybridization event. This coincides with dramatic climatic changes in that geological epoch shaping the composition of the vegetation.

  19. DIATOMS (BACILLARIOPHYTA) OF ISOLATED ISLANDS: NEW TAXA IN THE GENUS NAVICULA SENSU STRICTO FROM THE GALáPAGOS ISLANDS(1).

    PubMed

    Seddon, Alistair W R; Froyd, Cynthia A; Witkowski, Andrzej

    2011-08-01

    The diatoms (Bacillariophyta) from a coastal lagoon from the Diablas wetlands (Isla Isabela, the Galápagos Islands) were studied in material from surface samples and a sediment core spanning the past 2,700 years in order to examine evidence of diatom evolution under geographic isolation. The total number of taxa found was ∼100. Ultrastructural variation in valve morphology between members of Galápagos taxa was used to describe 10 species from the genus Navicula sensu stricto, which are new to science. Four taxa: N. isabelensis, N. isabelensoides, N. isabelensiformis, and N. isabelensiminor, shared several key characteristics that may be indicative of a common evolutionary heritage; these species therefore provide possible evidence for the in situ evolution of diatoms in the Galápagos coastal lagoons. Shared morphological characteristics include: (i) stria patterning in the central area, (ii) an elevated and thickened external raphe-sternum, (iii) external central raphe endings that are slightly deflected toward the valve primary side, and (iv) an arched valve surface. To explain these findings, two models were proposed. The first suggested limited lateral diatomaceous transport of Navicula species between the Galápagos and continental South America. Alternatively, these new species may be ecological specialists arising from the unique environmental conditions of the Galápagos coastal lagoons, which restrict the colonization of common diatom taxa and enable the establishment of novel, rare species. The Diablas wetlands are an important site for diatom research, where local-scale environmental changes have combined with global-scale biogeographic processes resulting in unique diatom assemblages.

  20. Experimental Infection of Ornithodoros erraticus sensu stricto with Two Portuguese African Swine Fever Virus Strains. Study of Factors Involved in the Dynamics of Infection in Ticks.

    PubMed

    Ribeiro, Rita; Otte, Joachim; Madeira, Sara; Hutchings, Geoff H; Boinas, Fernando

    2015-01-01

    African swine fever (ASF) is a frequently devastating hemorrhagic disease of domestic pigs and wild boar and Ornithodoros erraticus sensu stricto argasid ticks are the only biological vectors of African swine fever virus (ASFV) known to occur in Europe. Recently this disease emerged in Eastern Europe and Russian Federation, showing a huge potential for a rapid spread between countries. There is some risk of re-emergence of ASF in the countries where these ticks exist, that can contribute for the persistence of infection and compromise control measures. In this study we aimed to identify factors that determine the probability of infection and its dynamics in the tick vector Ornithodoros erraticus sensu stricto, with two Portuguese strains of ASFV. Our results suggest that these ticks have a high likelihood of excreting the two haemadsorbing ASF viruses of different host origins and that, in field surveys, the analysis of adults and 5th nymphal stage can provide the best chance of detecting virus infection. The results also indicate that infection of pigs with highly virulent ASF viruses will promote higher rates of infection and a higher likelihood for virus excretion by ticks. Nevertheless, there is also a risk, although lower, that ticks can become infected on pigs that have overcome the acute phase of infection, which was simulated in our study by membrane feeding ticks with low titres of virus. We believe these results can be valuable in designing and interpreting the results of ASF control programmes, and future work can also be undertaken as our dataset is released under open access, to perform studies in risk assessment for ASFV persistence in a region where O. erraticus sensu stricto ticks are present.

  1. Investigation of an unrecognized large-scale outbreak of Candida parapsilosis sensu stricto fungaemia in a tertiary-care hospital in China

    PubMed Central

    Wang, He; Zhang, Li; Kudinha, Timothy; Kong, Fanrong; Ma, Xiao-Jun; Chu, Yun-Zhuo; Kang, Mei; Sun, Zi-Yong; Li, Ruo-Yu; Liao, Kang; Lu, Juan; Zou, Gui-Ling; Xiao, Meng; Fan, Xin; Xu, Ying-Chun

    2016-01-01

    A data analysis of yeast collections from the National China Hospital Invasive Fungal Surveillance Net (CHIF-NET) programme in 2013 revealed a sudden increase in the proportion of Candida parapsilosis complex isolates (n = 98) in one participating hospital (Hospital H). Out of 443 yeast isolates submitted to the CHIF-NET reference laboratory by Hospital H (2010–2014), 212 (47.9%) were identified as C. parapsilosis sensu stricto by sequencing analysis of the internal transcribed spacer region and D1/D2 domain of the 26S rRNA gene. Among the 212 C. parapsilosis sensu stricto isolates, 176 (83.0%) bloodstream-based isolates and 25 isolates from tip cultures of various vascular catheters from 25 patients with candidaemia, were subjected to microsatellite genotyping, and a phylogenetic relationship analysis was performed for 152 isolates. Among the 152 isolates, 45 genotypes (T01 to T45) were identified, and two prevalent genotypes (63.8%) were found: T15 (n = 74, 48.7%) and T16 (n = 23, 15.1%). These two main clones were confined mainly to three different wards of the hospital, and they persisted for 16–25 months and 12–13 months, respectively. The lack of proper coordination between the clinical microbiology laboratory and infection control staff as part of public health control resulted in the failure to timely identify an outbreak, which led to the wide and long-term dissemination of C. parapsilosis sensu stricto in Hospital H. PMID:27251023

  2. Experimental Infection of Ornithodoros erraticus sensu stricto with Two Portuguese African Swine Fever Virus Strains. Study of Factors Involved in the Dynamics of Infection in Ticks

    PubMed Central

    Madeira, Sara; Hutchings, Geoff H.; Boinas, Fernando

    2015-01-01

    African swine fever (ASF) is a frequently devastating hemorrhagic disease of domestic pigs and wild boar and Ornithodoros erraticus sensu stricto argasid ticks are the only biological vectors of African swine fever virus (ASFV) known to occur in Europe. Recently this disease emerged in Eastern Europe and Russian Federation, showing a huge potential for a rapid spread between countries. There is some risk of re-emergence of ASF in the countries where these ticks exist, that can contribute for the persistence of infection and compromise control measures. In this study we aimed to identify factors that determine the probability of infection and its dynamics in the tick vector Ornithodoros erraticus sensu stricto, with two Portuguese strains of ASFV. Our results suggest that these ticks have a high likelihood of excreting the two haemadsorbing ASF viruses of different host origins and that, in field surveys, the analysis of adults and 5th nymphal stage can provide the best chance of detecting virus infection. The results also indicate that infection of pigs with highly virulent ASF viruses will promote higher rates of infection and a higher likelihood for virus excretion by ticks. Nevertheless, there is also a risk, although lower, that ticks can become infected on pigs that have overcome the acute phase of infection, which was simulated in our study by membrane feeding ticks with low titres of virus. We believe these results can be valuable in designing and interpreting the results of ASF control programmes, and future work can also be undertaken as our dataset is released under open access, to perform studies in risk assessment for ASFV persistence in a region where O. erraticus sensu stricto ticks are present. PMID:26366570

  3. First case of peritoneal cystic echinococcosis in a domestic cat caused by Echinococcus granulosus sensu stricto (genotype 1) associated to feline immunodeficiency virus infection.

    PubMed

    Armua-Fernandez, Maria Teresa; Castro, Oscar F; Crampet, Alejandro; Bartzabal, Álvaro; Hofmann-Lehmann, Regina; Grimm, Felix; Deplazes, Peter

    2014-04-01

    A new cystic echinococcosis case in a cat in Uruguay is reported herein. The cat was taken to a veterinary clinic in Rocha city, Uruguay, due to dyspnea, constipation and abdominal enlargement. During surgery a large quantity of cysts was retrieved from the abdominal cavity. The cysts were morphologically studied and confirmed as Echinococcus granulosus sensu stricto (genotype 1) by molecular tools using cytochrome oxidase submit 1 and small subunit ribosomal RNA gene as target genes. Moreover, for the first time a coinfection with feline immunodeficiency virus (FIV) was detected. FIV-induced immunosuppression could be a determining factor in the development of cystic echinococcosis in cats.

  4. Genetic stability and evolution of sigB allele used for Listeria sensu stricto subtyping and phylogenetic inference.

    PubMed

    Liao, Jingqiu; Wiedmann, Martin; Kovac, Jasna

    2017-04-07

    Sequencing of single genes remains an important tool that allows for rapid classification of bacteria. Sequencing of a portion of sigB, which encodes a stress responsive alternative sigma factor, has emerged as a commonly used molecular tool for initial characterization of diverse Listeria isolates. In this study, evolutionary approaches were used to assess the validity of sigB allelic typing for Listeria For a dataset of 4,280 isolates, sigB allelic typing showed a Simson Index of Discrimination of 0.96. Analyses of 164 sigB allelic types (ATs) found among the 6 Listeria sensu stricto (s.s.) species, representing these 4,280 isolates, indicates that neither frequent homologous recombination nor positive selection significantly contributed to the evolution of sigB, confirming its genetic stability. The molecular clock test provided evidence for unequal evolution rates across clades; L. welshimeri displayed the lowest sigB diversity and was the only species in which sigB evolved in a clocklike manner, implying a unique natural history. Among the four L. monocytogenes lineages, sigB evolution followed a molecular clock only in lineage IV. Moreover, sigB displayed a significant negative Tajima's D value in lineage II, suggesting a recent population bottleneck followed by lineage expansion. Absence of positive selection along with violation of the molecular clock suggested a nearly neutral mechanism of Listeria s.s. sigB evolution. While comparison with a whole genome sequence-based phylogeny revealed that sigB phylogeny did not correctly reflect the ancestry of L. monocytogenes lineage IV, the availability of a large sigB AT database did allow for accurate species classification.IMPORTANCEsigB allelic typing has been widely used for species delineation and subtyping of Listeria However, an informative evaluation of this method from an evolutionary perspective was missing to date. Our data indicate genetic stability of sigB, which supports that sigB allelic typing

  5. Influence of MKP medium stored for prolonged periods on growth and morphology of Borrelia afzelii, Borrelia garinii, and Borrelia burgdorferi sensu stricto.

    PubMed

    Veinović, Gorana; Cerar, Tjaša; Strle, Franc; Ružić-Sabljić, Eva

    2014-03-01

    Modified Kelly-Pettenkofer (MKP) medium is one of the several media used for isolation and cultivation of Borrelia. The aim of the study was to assess whether particular Borrelia species (B. afzelii, B. garinii, and B. burgdorferi sensu stricto) have the ability to grow in MKP medium stored at +4 °C for periods for 1 month up to 1 year, and how prolonged storage may influences Borrelia growth and morphology. The growth of Borrelia was evaluated after 5 days of incubation at 33 °C: cell count per mL, morphology, and motility were assessed. The results of this study showed that the duration of storage of MKP medium had statistically significant influence on growth of B. afzelii (p = 0.021) and B. garinii (p = 0.004), but not on growth of B. burgdorferi sensu stricto (p = 0.204), whereas duration of storage of the medium had no impact on Borrelia morphology and motility. The results of the study indicate that medium stored for more than 1 and up to 12 months supports Borrelia growth.

  6. Echinococcus granulosus sensu stricto, Echinococcus canadensis (G7), and Echinococcus ortleppi in fertile hydatid cysts isolated from cattle in Southern Brazil.

    PubMed

    Urach Monteiro, Danieli; de Azevedo, Maria Isabel; Weiblen, Carla; Correia Ribeiro, Tatiana; Emmanouilidis, Jéssica; Tonin, Alexandre Alberto; de Avila Botton, Sônia; de la Rue, Mário Luiz

    2016-12-01

    Echinococcosis is a cosmopolitan zoonotic infection that affects humans and animals. The aim of this study was to identify and characterize the fertile hydatid cysts from bovine viscera in order to verify different species and/or genotypes present in Southern Brazil. Firstly, cysts were collected from a slaughterhouse, which received animals from different regions of Rio Grande do Sul State (RS), considered an important area of occurrence of cystic echinococcosis. In total, 2396 cysts were analyzed by microscopy to verify the presence of protoscoleces. Protoscoleces were detected in 291 samples and were classified as fertile hydatid cysts. Total DNA was extracted from protoscoleces and amplified by polymerase chain reaction (PCR). Two hundred and fifty-one samples were identified by PCR and characterized as G5/G6/G7 genotypes, of which 40 belonged to Echinococcus granulosus sensu stricto (G1-G3). PCR was also performed, using G5-specific primers to identify 250 samples as Echinococcus ortleppi (G5). Only one sample was identified as Echinococcus canadensis (G7) by DNA sequencing using primers specific for the coxI gene. Phylogenetic analysis was also performed and identified three distinct groups E1 (G5), E2 (G7), and E3 (G1-G3), which were grouped according to similarity of their sequences. The study highlights the fact that E. granulosus sensu stricto, E. ortleppi, and E. canadensis (G7) were infecting cattle in RS, emphasizing the adaptation of different species of Echinococcus to this intermediate host.

  7. Studies on the Biology of Hypogeococcus pungens (sensu stricto) (Hemiptera: Pseudococcidae) in Argentina to Aid the Identification of the Mealybug Pest of Cactaceae in Puerto Rico

    PubMed Central

    Aguirre, M. B.; Diaz-Soltero, H.; Claps, L. E.; Saracho Bottero, A.; Triapitsyn, S.; Hasson, E.; Logarzo, G. A.

    2016-01-01

    Hypogeococcus pungens Granara de Willink, sensu stricto, is a serious pest of cacti in Puerto Rico threating many Caribbean islands. A classical biological control program for H. pungens was initiated for Puerto Rico in 2010 with a survey for natural enemies of H. pungens in its native range of Argentina. Biological differences were observed between populations of H. pungens sampled on Amaranthaceae and Cactaceae. Molecular studies suggested that H. pungens populations from different host plant families are likely a complex of species. Our objective was to study the biology of H. pungens sensu stricto on specimens collected in the same locality and host plant as the holotype [Tucumán Province, Argentina; Alternanthera pungens Kunth (Amaranthaceae)]. We were interested in the reproductive biology of females, longevity and survival of adults, the effect of temperature on the development, and nymph performance (survival and development) on five Cactaceae species. We found that H. pungens s.s. showed marked biological differences from the populations collected on Cactaceae and exported to Australia for the biological control of the cactus Harrisia spp. The main differences were the presence of deuterotoky parthenogenesis and the fact that H. pungens did not attack Cactaceae in the laboratory. Our results provide biological evidence that H. pungens is a species complex. We propose that the population introduced to Australia is neither Hypogeococcus festerianus Lizer y Trelles nor H. pungens, but an undescribed species with three circuli, and that the Hypogeococcus pest of cacti in Puerto Rico is not H. pungens. PMID:27324585

  8. Magma-sediment interactions in the Limagne trench (Massif Central, France): distinction between phreatomagmatic and stricto-sensu peperitic processes

    NASA Astrophysics Data System (ADS)

    Leibrandt, Sebastien; Bénard, Antoine; Brigaud, Benjamin

    2013-04-01

    can solely give birth to the stricto-sensu fluidal to blocky peperite microtexture, which we clearly distinguish for the first time in the Limagne area. A second outcome emerges thanks to the several approaches we use for microscopic characterization, which possibly reveal high-grade, non-explosive mingling of liquefied sediment with magma at the sub-millimetre scale. These observations provide new insights into peperite formation processes in carbonate sediments, when both considering experiments (e.g. Zimanowski and Büttner, 2002) and worldwide field observations in contrasting environments (e.g. McClintock & White, 2002). McClintock, M.K., White, J.D.L., 2002. Granulation of weak rock as a precursor to peperite formation: coal peperite, Coombs Hill, Antartica. Journal of Volcanology and Geothermal Research, 114, 205-217. Skilling, I.P., White, J.D.L., McPhie, J., 2002. Peperite: a review of magma-sediment mingling. Journal of Volcanology and Geothermal Research, 114, 1-17. Zimanowski, B., Büttner, R., 2002. Dynamic mingling of magma and liquefied sediments. Journal of Volcanology and Geothermal Research, 114, 37-44.

  9. A review of the Polystira clade--the Neotropic's largest marine gastropod radiation (Neogastropoda: Conoidea: Turridae sensu stricto).

    PubMed

    Todd, Jonathan A; Rawlings, Timothy A

    2014-11-18

    The Polystira clade (here comprising Polystira and Pleuroliria) is a poorly known but hyper-diverse clade within the neogastropod family Turridae (sensu stricto). It has extensively radiated within the tropics and subtropics of the Americas, to which it is endemic. In this paper we present a synthetic overview of existing information on this radiation together with new information on estimated species diversity, systematic relationships, a species-level molecular phylogenetic analysis and preliminary macroecological and diversification analyses, to serve as a platform for further study. We currently estimate that about 300 species (122 extant) are known from its 36 million year history but this number will undoubtedly increase as we extend our studies. We discuss the relationships of Polystira to other Neotropical Turridae (s.s.) and examine the taxonomy and systematics of the geologically oldest described members of the clade. To aid taxonomic description of shells we introduce a new notation for homologous major spiral cords. Focusing on key publications, we discuss in detail the changing historical understanding of the taxonomy of the clade and the relationships of its component genus-level taxa: Polystira Woodring, 1928, Pleuroliria de Gregorio, 1890, Josephina Gardner, 1945 and Oxytropa Glibert, 1955. We designate a neotype for Pleurotoma (Pleuroliria) supramirifica de Gregorio, 1890, to stabilize our understanding of this, the type species of Pleuroliria. Application of the name Oxytropa is restricted to the type species. The genus Polystira is conchologically re-described and for the first time we synthesize available information on the anatomy, feeding and toxinology, reproduction and life history, larval modes and life habits, and geographic and bathymetric ranges of its species. We give an updated list of the 19 formally described living species and present the pitfalls of the currently poor species-level taxonomy of Polystira using case examples. We

  10. Depicting the Discrepancy between Tri Genotype and Chemotype on the Basis of Strain CBS 139514 from a Field Population of F. graminearum Sensu Stricto from Argentina

    PubMed Central

    Kulik, Tomasz; Buśko, Maciej; Bilska, Katarzyna; Ostrowska-Kołodziejczak, Anna; van Diepeningen, Anne D.; Perkowski, Juliusz; Stenglein, Sebastian

    2016-01-01

    Recent studies on a field population of F. graminearum sensu stricto from Argentina revealed an atypical panel of strains identified through PCR genotyping as 15ADON genotypes, but producing high levels of 3ADON. Based on representative strain CBS 139514, we asked if the discrepancy between the trichothecene genotype and chemotype might result from an inter-chemotype recombination of the chemotype-determining genes. To answer this, we sequenced the complete core Tri gene cluster (around 30,200 bp) from this strain and compared its sequence to sequence data of typical type B trichothecene genotypes/chemotypes. Sequence alignment showed that CBS 139514 has an identical sequence within the entire core Tri cluster to the 15ADON genotype. The revealed discrepancy underlines the need for using both molecular and chemical methods for reliable characterization of toxigenic strains of Fusarium. PMID:27845742

  11. Natural antibiotic susceptibility of strains of Serratia marcescens and the S. liquefaciens complex: S. liquefaciens sensu stricto, S. proteamaculans and S. grimesii.

    PubMed

    Stock, I; Grueger, T; Wiedemann, B

    2003-07-01

    The natural susceptibility of 77 strains of Serratia marcescens and 41 strains of the S. liquefaciens complex (S. liquefaciens sensu stricto (n=21), S. grimesii (n=10), S. proteamaculans (n=10)) to 70 antibiotics was examined using a microdilution procedure in Isosensitest broth (all strains) and cation-adjusted Mueller Hinton broth (some strains). All species were naturally resistant to benzylpenicillin, oxacillin, cefaclor, cefazolin, cefuroxime, numerous macrolides, lincosamides, streptogramins, glycopeptides, rifampicin and fusidic acid. Uniform natural sensitivity was found to most aminoglycosides, several acylureidopenicillins, ticarcillin, newer cephalosporins, carbapenems, aztreonam, quinolones and antifolates. Species-related differences in susceptibility affecting clinical assessment criteria were found for several agents. S. marcescens was less susceptible to some aminoglycosides than species of the S. liquefaciens group. It was the only species that was uniformly naturally resistant to tetracycline, amoxycillin, amoxycillin/clavulanate and loracarbef. Species of the S. liquefaciens group were naturally resistant and intermediate or naturally intermediate to the latter agents. Differences in susceptibility among the species of the S. liquefaciens complex were generally small. S. proteamaculans was most susceptible to sulphamethoxazole. S. liquefaciens sensu stricto was less susceptible than S. grimesii and S. proteamaculans to tetracyclines, chloramphenicol and nitrofurantoin; it was the only species uniformly naturally resistant to fosfomycin. This study suggested that all species examined probably express chromosomally-encoded AmpC beta-lactamases, but the amount of enzyme may vary from species to species. The naturally-occurring low-level expression of the S. marcescens aminoglycoside 6'-acetyltransferase AAC(6')-Ic and its absence in other Serratia spp. was supported by the data. All species of the S. liquefaciens complex should be considered as

  12. Studies on the Biology of Hypogeococcus pungens (sensu stricto) (Hemiptera: Pseudococcidae) in Argentina to Aid the Identification of the Mealybug Pest of Cactaceae in Puerto Rico.

    PubMed

    Aguirre, M B; Diaz-Soltero, H; Claps, L E; Saracho Bottero, A; Triapitsyn, S; Hasson, E; Logarzo, G A

    2016-01-01

    Hypogeococcus pungens Granara de Willink, sensu stricto, is a serious pest of cacti in Puerto Rico threating many Caribbean islands. A classical biological control program for H. pungens was initiated for Puerto Rico in 2010 with a survey for natural enemies of H. pungens in its native range of Argentina. Biological differences were observed between populations of H. pungens sampled on Amaranthaceae and Cactaceae. Molecular studies suggested that H. pungens populations from different host plant families are likely a complex of species. Our objective was to study the biology of H. pungens sensu stricto on specimens collected in the same locality and host plant as the holotype [Tucumán Province, Argentina; Alternanthera pungens Kunth (Amaranthaceae)]. We were interested in the reproductive biology of females, longevity and survival of adults, the effect of temperature on the development, and nymph performance (survival and development) on five Cactaceae species. We found that H. pungens s.s showed marked biological differences from the populations collected on Cactaceae and exported to Australia for the biological control of the cactus Harrisia spp. The main differences were the presence of deuterotoky parthenogenesis and the fact that H. pungens did not attack Cactaceae in the laboratory. Our results provide biological evidence that H. pungens is a species complex. We propose that the population introduced to Australia is neither Hypogeococcus festerianus Lizer y Trelles nor H. pungens, but an undescribed species with three circuli, and that the Hypogeococcus pest of cacti in Puerto Rico is not H. pungens. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America.

  13. Survey and first molecular characterization of Echinococcus granulosus sensu stricto (G1) in Pampas fox (Lycalopex gymnocercus) in Buenos Aires province, Argentina.

    PubMed

    Scioscia, Nathalia Paula; Petrigh, Romina Sandra; Beldomenico, Pablo Martín; Fugassa, Martín; Denegri, Guillermo María

    2016-06-01

    Echinococcosis is a zoonosis caused by tapeworms of the genus Echinococcus. Echinococcus granulosus sensu lato (s. l.) has a world-wide distribution and its transmission is primarily maintained in a synanthropic cycle with dogs as definitive hosts and livestock species as intermediate hosts. However, many wild canids also function as definitive hosts for E. granulosus s. l. Echinococcosis in humans is mainly caused by E. granulosus sensu stricto (s. s.) G1 genotype. In the present work, we expanded the epidemiological study on echinococcosis reported cases in Pampas fox (Lycalopex gymnocercus) to provide a prevalence estimate for rural areas of southern Buenos Aires province, Argentina. Ninety-five whole intestines were analyzed using the sedimentation and counting technique with a result of 83 foxes (87.37%) harboring at least one helminth species. E. granulosus s. l. adults were found in one Pampas fox (1.05%). These adult helminthes were E. granulosus s. s. (G1) according to the genotyping analysis of a 450-bp region of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Reprint of "Survey and first molecular characterization of Echinococcus granulosus sensu stricto (G1) in Pampas fox (Lycalopex gymnocercus) in Buenos Aires province, Argentina".

    PubMed

    Scioscia, Nathalia Paula; Petrigh, Romina Sandra; Beldomenico, Pablo Martín; Fugassa, Martín; Denegri, Guillermo María

    2017-01-01

    Echinococcosis is a zoonosis caused by tapeworms of the genus Echinococcus. Echinococcus granulosus sensu lato (s. l.) has a world-wide distribution and its transmission is primarily maintained in a synanthropic cycle with dogs as definitive hosts and livestock species as intermediate hosts. However, many wild canids also function as definitive hosts for E. granulosus s. l. Echinococcosis in humans is mainly caused by E. granulosus sensu stricto (s. s.) G1 genotype. In the present work, we expanded the epidemiological study on echinococcosis reported cases in Pampas fox (Lycalopex gymnocercus) to provide a prevalence estimate for rural areas of southern Buenos Aires province, Argentina. Ninety-five whole intestines were analyzed using the sedimentation and counting technique with a result of 83 foxes (87.37%) harboring at least one helminth species. E. granulosus s. l. adults were found in one Pampas fox (1.05%). These adult helminthes were E. granulosus s. s. (G1) according to the genotyping analysis of a 450-bp region of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Description of Trilineellus clathrocutis n.g., n.sp. (Tylenchorhynchinae: Tylenchida Thorne, 1949) with a Key to Species and Observations on Tylenchorhynchus sensu stricto

    PubMed Central

    Lewis, Stephen A.; Golden, A. Morgan

    1981-01-01

    TrilineeIlus clathrocutis n.g., n.sp. is described and illustrated. It was found as an associate of corn (Zea mays) in Stockton, Georgia, USA, and is related to a group of Tylenchorhynchus sensu lato species having three lines in nonareolated lateral fields. This new species is closely related to Tylenehorhynehus divittatus Siddiqi 1961, T. sculptus Seinhorst 1963, and T. triglyphus Seinhorst 1963 (syn. T. chonai Sethi & Swarup 1968) Tarjan 1973. It differs from these species primarily by having longitudinal striae on the body. These four species are differentiated from Tylenchorhynchus sensu stricto by having three lateral lines instead of four. They differ from Uliginotylenchus Siddiqi 1971 by having nonareolated lateral fields, fewer than 25 annules on conoid rounded tails, differently shaped gubernacula, nonattenuated stylets, and other distinctive characters. They differ from Triversus Sher 1973 by having the male tail enclosed by the bursa and by having rounded female tails. SEM observations of T. clathrocutis reveal a cuticle deeply cut by longitudinal and horizontal striae and bearing wide (> 2.0 μm) annules. Trilineellus is proposed to accommodate the new species and the three-incisured species still within Tylenchorhynchus. Tylenchorhynchus is thereby the repository for species within Tylenchorhynchinae having four lines in the lateral field, no conspicuous labial disc, and bursa enclosing the male tail. PMID:19300734

  16. [Nucleotide sequence analysis of a species specific probe by an inserted fragment from recombinant plasmid pCX7 of L. interrogans sensu stricto serovar lai].

    PubMed

    Dai, B; Xiao, J; Yan, Z; Shen, C; Li, S; Fang, Z

    1998-12-01

    The etiological agents of leptospirosis are the pathogenic leptospires (L. interrogans sensu lato) which can be divided into 223 serovars organized into 23 serogroups. The serovar remains the basic taxon, but serotyping may now be accomplished and recognized by acceptable methods. Complementary molecular approaches are being used extensively to assess genetic relatedness amongst leptospires with restriction endonuclese analysis (REA), pulse field gel electrophoresis (PFGE) and DNA-DNA hybridization as well established tools. However, the method is cumbersome and unsuitable for routine application. To develop a sensitive and specific method for identification of pathogenic leptospires, a genomic library of L. interrogans sensu stricto serovar lai was constructed with the plasmid vector pUC9. A recombinant plasmid, designated pCX7 which has homologous fragment of pathogenic leptospires was screened from the bank. pCX7 could recognize pathogenic leptospiral DNA fragment 1.7 kb of strain 017 without cross hybridization to nonpathogenic leptospiral DNA. Inserted fragment of pCX7 DNA sequencing was performed by Dr. Yan Zhengxin (Max-Plank-Institut fur Biology, Tubingen, Germany). Insert fragment was cloned into pBluescript and sequenced by using ABI(Applied Bio. Systems, Model 373A). Nucleotide sequences were analyzed by Dr. Xiao Jianguo (Texas University Medical School and School of Public Health, Center for Infectious Diseases) using a suit of computer program (NIH). One open reading frame of 306 nucleotids were identified. There were identifiable initiation codons, terminators, pribnow box and sextama box within the sequenced regions. These results further confirmed that the little homology between L. interrogans sensu strito and L. borgpeterseni serovar javanica, L. inadai serovar ranarun and serovar manhao (L. genomospecies 2), L. biflexa serovar patoc, L. illini. pCX7 DNA probe could provide a base for identification and classification of leptospires.

  17. Spatial distribution of the sibling species of Anopheles gambiae sensu lato (Diptera: Culicidae) and malaria prevalence in Bayelsa State, Nigeria

    PubMed Central

    2014-01-01

    Background Much of the confusing ecophenotypic plasticity of Anopheles gambiae sensu lato is attributable to the differential biological traits of the sibling species, with their heterogeneous geographical distribution, behavioral dissimilarities and divergent population dynamics. These differences are critical to their roles in malaria transmission. Studies were, therefore, undertaken on the spatial distribution of these species and malaria prevalence rates in Bayelsa State, September, 2008-August 2010. Methods Mosquito sampling was in 7 towns/villages in 7 Local Government Areas (LGAs) in 3 eco-vegetational zones: Fresh Water Swamp Forest (FWSF): Sagbama, Yenagoa, Kolokuma-Opokuma LGAs; Brackish Water Swamp Forest (BWSF): Ogbia, Ekeremor, Southern Ijaw LGAs; Mangrove Water Forest (MWF): Nembe LGA. Adults were collected twice quarterly by the Pyrethrum Spray Catch (PSC) technique. Anopheles was separated morphologically and the sibling species PCR- identified. Simultaneously, malaria prevalence rates were calculated from data obtained by the examination of blood smears from consenting individuals at hospitals/clinics. Results An. gambiae s.s. was dominant across the 3-eco-vegetational zones. Spatial distribution analyses by cell count and nearest neighbor techniques indicated a tendency to clustering of species. An. gambiae s.s. and An. arabiensis clustered in Ekeremor LGA while these 2 species and An. melas aggregated in Nembe. The gonotrophic (physiological) status examination revealed that 34.3, 23.5, 23.1 and 18.4% of the population were fed, unfed, gravid and half gravid respectively. The highest malaria prevalence rates were obtained at Kolokuma-Opokuma and Nembe LGAs. Variation in prevalence rates among LGAs was significant (t = 5.976, df = 6, p-value = 0.002, p < 0.05). The highest prevalence rate was in the age group, 30-39 yrs, while the lowest prevalence was in the 0-9 yrs group. Conclusion High malaria prevalence rates were associated

  18. Phylogenomic analyses of clostridia and identification of novel protein signatures that are specific to the genus Clostridium sensu stricto (cluster I).

    PubMed

    Gupta, Radhey S; Gao, Beile

    2009-02-01

    The species of Clostridium comprise a very heterogeneous assemblage of bacteria that do not form a phylogenetically coherent group. It has been proposed previously that only a subset of the species of Clostridium that form a distinct cluster in the 16S rRNA tree (cluster I) should be regarded as the true representatives of the genus Clostridium (i.e. Clostridium sensu stricto). However, this cluster is presently defined only in phylogenetic terms, and no biochemical, molecular or phenotypic characteristic is known that is unique to species from this cluster. We report here phylogenomic and comparative analyses based on sequenced clostridial genomes in an attempt to bridge this gap and to clarify the evolutionary relationships among species of clostridia. In phylogenetic trees for species of clostridia based on concatenated sequences for 37 highly conserved proteins, the species of Clostridium cluster I formed a strongly supported clade that was separated from all other clostridia by a long branch. Several other Clostridium species that are not part of this cluster grouped reliably with other species of clostridia in a number of well-resolved clades. Our comparative genomic analyses have identified three conserved indels in three highly conserved proteins (a 4 aa insert in DNA gyrase A, a 1 aa deletion in ATP synthase beta subunit and a 1 aa insert in ribosomal protein S2) that are unique to the species of Clostridium cluster I and are not found in any other bacteria. blastp searches on various proteins in the genomes of Clostridium tetani E88 and Clostridium perfringens SM101 have also identified more than 10 proteins that are found uniquely in the cluster I species. These results provide evidence that the species of Clostridium cluster I not only are phylogenetically distinct but also share many unique molecular characteristics. These newly identified molecular markers provide useful tools to define and circumscribe the genus Clostridium sensu stricto in more

  19. A broad-range survey of ticks from livestock in Northern Xinjiang: changes in tick distribution and the isolation of Borrelia burgdorferi sensu stricto.

    PubMed

    Wang, Yuan-Zhi; Mu, Lu-Meng; Zhang, Ke; Yang, Mei-Hua; Zhang, Lin; Du, Jing-Yun; Liu, Zhi-Qiang; Li, Yong-Xiang; Lu, Wei-Hua; Chen, Chuang-Fu; Wang, Yan; Chen, Rong-Gui; Xu, Jun; Yuan, Li; Zhang, Wan-Jiang; Zuo, Wei-Ze; Shao, Ren-Fu

    2015-09-04

    Borreliosis is highly prevalent in Xinjiang Uygur Autonomous Region, China. However, little is known about the presence of Borrelia pathogens in tick species in this region, in addition Borrelia pathogens have not been isolated from domestic animals. We collected adult ticks from domestic animals at 19 sampling sites in 14 counties in northern Xinjiang from 2012 to 2014. Ticks were identified to species by morphology and were molecularly analysed by sequences of mitochondrial 16S rDNA gene; 4-8 ticks of each species at every sampling site were sequenced. 112 live adult ticks were selected for each species in every county, and were used to culture Borrelia pathogens; the genotypes were then determined by sequences of the 5S-23S rRNA intergenic spacer and the outer surface protein A (ospA) gene. A total of 5257 adult ticks, belonging to four genera and seven species, were collected. Compared with three decades ago, the abundance of the five common tick species during the peak ixodid tick season has changed. Certain tick species, such as Rhipicephalus turanicus (Rh. turanicus), was found at Jimusaer, Yining, Fukang, and Chabuchaer Counties for the first time. Additionally, the sequence analyses showed that the Hyalomma asiaticum (Hy. asiaticum), Haemaphysalis punctata (Ha. punctata), and Dermacentor marginatus (D. marginatus) that were collected from different sampling sites (≥3 sites) shared identical 16S rDNA sequences respectively. For the tick species that were collected from the same county, such as Hy. asiaticum from Shihezi County and Rh. turanicus from Yining County, their 16S rDNA sequences showed genetic diversity. In addition, sixteen Borrelia isolates were found in Hy. asiaticum, Ha. punctata, D. marginatus and Rh. turanicus, which infested cattle, sheep, horse and camel in Yining, Chabuchaer, Shihezi and Shawan Counties. All of the isolates were genetically identified as B. Burgdorferi sensu stricto. Warmer and wetter climate may have contributed to the

  20. First molecular identification of Echinococcus vogeli and Echinococcus granulosus (sensu stricto) G1 revealed in feces of domestic dogs (Canis familiaris) from Acre, Brazil.

    PubMed

    das Neves, Leandro Batista; Teixeira, Paulo Eduardo Ferlini; Silva, Sidnei; de Oliveira, Fernanda Bittencourt; Garcia, Daniel Daipert; de Almeida, Fernanda Barbosa; Rodrigues-Silva, Rosângela; Machado-Silva, José Roberto

    2017-01-14

    Echinococcus granulosus (sensu lato) (s.l.) and Echinococcus vogeli are causative agents of chronic zoonotic diseases such as cystic and polycystic echinococcosis, respectively. In Brazil, polycystic echinococcosis has a restricted geographical distribution in the North Region, while cystic echinococcosis is observed in the South Region. Domestic dogs (Canis familiaris) fed with raw viscera represent a risk factor for E. granulosus (s.l.) infection in the South Region. Although this practice is frequent, it remains unclear whether domestic dogs are infected with E. vogeli in the state of Acre, located in the Amazon basin in the North Region of Brazil. The aim of this study was to investigate this gap in the polycystic echinococcosis epidemiology. Sixty-five fecal samples were collected from the ground in five municipalities (Sena Madureira, n = 14; Rio Branco, n = 06; Bujari, n = 06; Xapuri, n = 30; and Epitaciolândia, n = 09) located in the state of Acre, northern Brazil. The samples were screened for parasites by copro-PCR using the cox1 gene associated with automated sequencing. Echinococcus vogeli was molecularly confirmed in a sample from Sena Madureira and E. granulosus (sensu stricto) (s.s.) (G1) in a sample from Rio Branco. These findings indicate that molecular assays are useful in typing Echinococcus taxa from fecal samples of dogs in northern Brazil. The present study is the first molecular record of E. vogeli in domestic dogs found in the state of Acre, reinforcing their role as a source of infection for humans. Because E. granulosus (s.s.) (G1) was detected for the first time in the North Region, from the epidemiological standpoint this finding is highly relevant, because it expands the known geographical distribution, which was previously restricted to the South Region of Brazil.

  1. Genetic characterization of human hydatid cysts shows coinfection by Echinococcus canadensis G7 and Echinococcus granulosus sensu stricto G1 in Argentina.

    PubMed

    Debiaggi, María Florencia; Soriano, Silvia Viviana; Pierangeli, Nora Beatriz; Lazzarini, Lorena Evelina; Pianciola, Luis Alfredo; Mazzeo, Melina Leonor; Moguillansky, Sergio; Farjat, Juan Angel Basualdo

    2017-07-18

    Human cystic echinococcosis caused by the larval stage of Echinococcus granulosus sensu lato (s.l.) is a highly endemic disease in the province of Neuquén, Patagonia, Argentina. Human infections with E. granulosus sensu stricto (s.s.) G1 and Echinococcus canadensis G6 were reported in Neuquén in previous studies, whereas four genotypes were identified in livestock: G1, G3, G6, and G7. The aim of this study was to identify the genotypes of E. granulosus s.l. isolates from humans of Neuquén province, Patagonia, Argentina, through the 2005-2014 period. Twenty six hydatid cysts were obtained from 21 patients. The most frequent locations were the liver and lungs. Single cysts were observed in 81.0% of patients, and combined infection of liver and lungs was detected in 9.5% of cases. Partial sequencing of mitochondrial cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase subunit 1 (nad1) genes identified the presence of E. granulosus s.s. G1 (n = 11; 42.3%) including three different partial sequences; E. canadensis G6 (n = 14; 53.8%) and E. canadensis G7 (n = 1; 3.9%). Coinfection with G1 and G7 genotypes was detected in one patient who harbored three liver cysts. Most of the liver cysts corresponded to G1 and G6 genotypes. This study presents the first report in the Americas of a human infection with E. canadensis G7 and the second worldwide report of a coinfection with two different species and genotypes of E. granulosus s.l in humans. The molecular diversity of this parasite should be considered to redesign or improve the control program strategies in endemic regions.

  2. Floral structure of Emmotum (Icacinaceae sensu stricto or Emmotaceae), a phylogenetically isolated genus of lamiids with a unique pseudotrimerous gynoecium, bitegmic ovules and monosporangiate thecae

    PubMed Central

    Endress, Peter K.; Rapini, Alessandro

    2014-01-01

    Background and Aims Icacinaceae sensu stricto consist of a group of early branching lineages of lamiids whose relationships are not yet resolved and whose detailed floral morphology is poorly known. The most bizarre flowers occur in Emmotum: the gynoecium has three locules on one side and none on the other. It has been interpreted as consisting of three fertile and two sterile carpels or of one fertile carpel with two longitudinal septa and two sterile carpels. This study focused primarily on the outer and inner morphology of the gynoecium to resolve its disputed structure, and ovule structure was also studied. In addition, the perianth and androecium were investigated. Methods Flowers and floral buds of two Emmotum species, E. harleyi and E. nitens, were collected and fixed in the field, and then studied by scanning electron microscopy. Microtome section series were used to reconstruct their morphology. Key Results The gynoecium in Emmotum was confirmed as pentamerous, consisting of three fertile and two sterile carpels. Each of the three locules behaves as the single locule in other Icacinaceae, with the placenta of the two ovules being identical, which shows that three fertile carpels are present. In addition, it was found that the ovules are bitegmic, which is almost unique in lamiids, and that the stamens have monosporangiate thecae, which also occurs in the closely related family Oncothecaceae, but is not known from any other Icacinaceae sensu lato so far. Conclusions The flowers of Emmotum have unique characters at different evolutionary levels: the pseudotrimerous gynoecium at angiosperm level, the bitegmic ovules at lamiid level and the monosporangiate thecae at family or family group level. However, in general, the floral morphology of Emmotum fits well in Icacinaceae. More comparative research on flower structure is necessary in Icacinaceae and other early branching lineages of lamiids to better understand the initial evolution of this large lineage of

  3. Dose-response tests and semi-field evaluation of lethal and sub-lethal effects of slow release pyriproxyfen granules (Sumilarv®0.5G) for the control of the malaria vectors Anopheles gambiae sensu lato.

    PubMed

    Mbare, Oscar; Lindsay, Steven W; Fillinger, Ulrike

    2013-03-14

    Recently research has shown that larviciding can be an effective tool for integrated malaria vector control. Nevertheless, the uptake of this intervention has been hampered by the need to re-apply larvicides frequently. There is a need to explore persistent, environmentally friendly larvicides for malaria vector control to reduce intervention efforts and costs by reducing the frequency of application. In this study, the efficacy of a 0.5% pyriproxyfen granule (Surmilarv®0.5G, Sumitomo Chemicals) was assessed for the control of Anopheles gambiae sensu stricto and Anopheles arabiensis, the major malaria vectors in sub-Saharan Africa. Dose-response and standardized field tests were implemented following standard procedures of the World Health Organization's Pesticide Evaluation Scheme to determine: (i) the susceptibility of vectors to this formulation; (ii) the residual activity and appropriate retreatment schedule for field application; and, (iii) sub-lethal impacts on the number and viability of eggs laid by adults after exposure to Sumilarv®0.5G during larval development. Anopheles gambiae s.s. and An. arabiensis were highly susceptible to Sumilarv®0.5G. Estimated emergence inhibition (EI) values were very low and similar for both species. The minimum dosage that completely inhibited adult emergence was between 0.01-0.03 parts per million (ppm) active ingredient (ai). Compared to the untreated control, an application of 0.018 ppm ai prevented 85% (95% confidence interval (CI) 82%-88%) of adult emergence over six weeks under standardized field conditions. A fivefold increase in dosage of 0.09 ppm ai prevented 97% (95% CI 94%-98%) emergence. Significant sub-lethal effects were observed in the standardized field tests. Female An. gambiae s.s. that were exposed to 0.018 ppm ai as larvae laid 47% less eggs, and females exposed to 0.09 ppm ai laid 74% less eggs than females that were unexposed to the treatment. Furthermore, 77% of eggs laid by females exposed to 0

  4. [Susceptibility status of Anopheles gambiae sensu lato to insecticides commonly used for malaria control in Mali].

    PubMed

    Keïta, M; Traoré, S; Sogoba, N; Dicko, A M; Coulibaly, B; Sacko, A; Doumbia, S; Traoré, S F

    2016-02-01

    The objective of this work was to monitor the susceptibility of malaria vectors to insecticides in nine sentinel sites of the National Malaria Control Program in Mali. The study was performed during the rainy seasons of 2010 and 2011. WHO bioassays were conducted using F0 and/or F1 from wild collected females. The insecticides used were lambda-cyhalothrin 0.05%, DDT 4%, permethrin 0.75%, deltamethrin 0.05%, bendiocarb 0.1% and fenitrothion 1.0%. Results showed suspicion of resistance to pyrethroids and organochlorine in An. gambiae s.l. at almost all the sites except Yanfolila where the vector was susceptible to lambda-cyhalothrin (98.0%) [CI 95%, 98-99.8] and to DDT (100%). An. gambiae s.l. was susceptible to bendiocarb in five of the sites (Gao, Bougouni, Djenné, Yanfolila, Tombouctou) while there was a suspicion of resistance at the other sites (Kati, Niono, Bandiagara, Kita). Fenitrothion remains efficient except in the rice area of Niono, where there was a suspicion of resistance with a mortality rate of 92% [IC 95% 88.3-94.8]. Thus, it could be used as an alternative insecticide for IRS in Mali. These results show resistance to pyrethroids, the main insecticide family used in public health (and to some extent in agriculture). This could compromise the malaria vector control efforts in Mali where pyrethroids are used for both in bed nets and in IRS.

  5. Coinfection of western gray squirrel (Sciurus griseus) and other sciurid rodents with Borrelia burgdorferi sensu stricto and Anaplasma phagocytophilum in California.

    PubMed

    Nieto, Nathan C; Leonhard, Sarah; Foley, Janet E; Lane, Robert S

    2010-01-01

    Overlapping geographic distributions of tick-borne disease agents utilizing the same tick vectors are common, and coinfection of humans, domestic animals, wildlife, and ticks with both Borrelia burgdorferi and Anaplasma phagocytophilum has been frequently reported. This study was undertaken in order to evaluate the prevalence of both B. burgdorferi sensu stricto (hereinafter referred to as B. burgdorferi) and A. phagocytophilum in several species of sciurid rodents from northern California, USA. Rodents were either collected dead as road-kills or live-trapped in four state parks from 13 counties. Thirty-seven western gray squirrels (Sciurus griseus), nine nonnative eastern gray squirrels (S. carolinensis) and an eastern fox squirrel (S. niger), four Douglas squirrels (Tamiasciurus douglasii), and two northern flying squirrels (Glaucomys sabrinus) were tested by polymerase chain reaction (PCR) and serology for evidence of coinfection. Of the 14 individual S. griseus that were PCR-positive for B. burgdorferi, two (14%) also were PCR-positive for A. phagocytophilum and 11 (79%) had serologic evidence of A. phagocytophilum exposure. Two of the four Douglas squirrels were PCR positive for B. burgdorferi and seropositive to A. phagocytophilum. Evidence of coinfection with these zoonotic pathogens in western gray squirrels suggests that both bacteria may be maintained in a similar transmission cycle involving this sciurid and the western black-legged tick Ixodes pacificus, the primary bridging vector to humans in the far-western US.

  6. [Profile of the demand for stricto sensu graduate programs offered by the University of São Paulo at Ribeirão Preto College of Nursing].

    PubMed

    Almeida, Maria Cecília Puntel de; Robazzi, Maria Lúcia do Carmo Cruz; Scochi, Carmen Gracinda Silvan; Bueno, Sonia Maria Villela; Cassiani, Silvia Helena de Bortolli; Saeki, Toyoko; Ferriani, Maria das Graças Carvalho; Santana, Mary Elizabeth de

    2004-01-01

    This study aimed at describing and analyzing the profile of the demand for stricto sensu graduate programs--master and doctoral degree offered by the University of São Paulo at Ribeirão Preto College of Nursing from 1975 to 2002. Data were collected through the records of the students enrolled in the programs. The sample consisted of 979 students: 210 from the Psychiatric Nursing Program, 375 from the Fundamental Nursing Program, 203 from the Public Health Program and 189 from the Interunit Doctoral Program. The majority were women, married, with an average age of 32 years (master) and 38 years (doctoral). 93% were nurses. 60% came from universities and 25.6% from health services. 11.3% were not working, besides the ones that recently graduated. 71.2% were from the South East of Brazil, 9.8% from the South, 6.9% from the Central-Western region, 6.8% from the North East and 18% from the North. The foreign students correspond to 3.4%. Findings reinforce the graduate policies adopted by the college with respect to expected student profile.

  7. Genetic diversity of Borrelia burgdorferi sensu stricto in Peromyscus leucopus, the primary reservoir of Lyme disease in a region of endemicity in southern Maryland.

    PubMed

    Anderson, Jennifer M; Norris, Douglas E

    2006-08-01

    In the north central and northeastern United States, Borrelia burgdorferi sensu stricto, the etiologic agent of Lyme disease (LD), is maintained in an enzootic cycle between the vector, Ixodes scapularis, and the primary reservoir host, Peromyscus leucopus. Genetic diversity of the pathogen based on sequencing of two plasmid-located genes, those for outer surface protein A (ospA) and outer surface protein C (ospC), has been examined in both tick and human specimens at local, regional, and worldwide population scales. Additionally, previous studies have only been conducted with tick or human specimens at the local population level in areas with high LD transmission rates. This study examined the genetic diversity of circulating borreliae in the reservoir population from a large region of the western coastal plains of southern Maryland, where moderate numbers of human LD cases are reported. Six ospA mobility classes, including two that were not previously described, and eight ospC groups were found among the P. leucopus samples. Twenty-five percent of all specimens were infected with more than one ospA or ospC variant. The frequency distribution of variants was homogeneous, both locally and spatially. The spirochete diversity found in Maryland was not as high as that observed among northern tick populations, yet similar genotypes were observed in both populations. These results also show that mice are important for maintaining Borrelia variants, even rare variants, and that reservoir populations should therefore be considered when assessing the diversity of B. burgdorferi.

  8. High-resolution melting analysis (HRM) for differentiation of four major Taeniidae species in dogs Taenia hydatigena, Taenia multiceps, Taenia ovis, and Echinococcus granulosus sensu stricto.

    PubMed

    Dehghani, Mansoureh; Mohammadi, Mohammad Ali; Rostami, Sima; Shamsaddini, Saeedeh; Mirbadie, Seyed Reza; Harandi, Majid Fasihi

    2016-07-01

    Tapeworms of the genus Taenia include several species of important parasites with considerable medical and veterinary significance. Accurate identification of these species in dogs is the prerequisite of any prevention and control program. Here, we have applied an efficient method for differentiating four major Taeniid species in dogs, i.e., Taenia hydatigena, T. multiceps, T. ovis, and Echinococcus granulosus sensu stricto. High-resolution melting (HRM) analysis is simpler, less expensive, and faster technique than conventional DNA-based assays and enables us to detect PCR amplicons in a closed system. Metacestode samples were collected from local abattoirs from sheep. All the isolates had already been identified by PCR-sequencing, and their sequence data were deposited in the GenBank. Real-time PCR coupled with HRM analysis targeting mitochondrial cox1 and ITS1 genes was used to differentiate taeniid species. Distinct melting curves were obtained from ITS1 region enabling accurate differentiation of three Taenia species and E. granulosus in dogs. The HRM curves of Taenia species and E .granulosus were clearly separated at Tm of 85 to 87 °C. In addition, double-pick melting curves were produced in mixed infections. Cox1 melting curves were not decisive enough to distinguish four taeniids. In this work, the efficiency of HRM analysis to differentiate four major taeniid species in dogs has been demonstrated using ITS1 gene.

  9. trans-Cinnamic and Chlorogenic Acids Affect the Secondary Metabolic Profiles and Ergosterol Biosynthesis by Fusarium culmorum and F. graminearum Sensu Stricto.

    PubMed

    Kulik, Tomasz; Stuper-Szablewska, Kinga; Bilska, Katarzyna; Buśko, Maciej; Ostrowska-Kołodziejczak, Anna; Załuski, Dariusz; Perkowski, Juliusz

    2017-06-22

    Plant-derived compounds limiting mycotoxin contamination are currently of major interest in food and feed production. However, their potential application requires an evaluation of their effects on fungal secondary metabolism and membrane effects. In this study, different strains of Fusarium culmorum and F. graminearum sensu stricto were exposed to trans-cinnamic and chlorogenic acids on solid YES media. Fusaria produced phenolic acids, whose accumulation was lowered by exogenous phenolic compounds. In addition, fungi reduced exogenous phenolic acids, leading either to their conversion or degradation. trans-Cinnamic acid was converted to caffeic and ferulic acids, while chlorogenic acid was degraded to caffeic acid. The latter underwent further degradation to protocatechuic acid. Fungal-derived trans-cinnamic acid, as the first intermediate of the shikimate pathway, increased after chlorogenic acid treatment, presumably due to the further inhibition of the conversion of trans-cinnamic acid. Exogenous trans-cinnamic and chlorogenic acid displayed the inhibition of mycotoxin production by Fusaria, which appeared to be largely dependent on the phenolic compound and its concentration and the assayed strain. Exogenous phenolic acids showed different effects on ergosterol biosynthesis by fungi. It was found that the production of this membrane sterol was stimulated by trans-cinnamic acid, while chlorogenic acid negatively impacted ergosterol biosynthesis, suggesting that phenolic acids with stronger antifungal activities may upregulate ergosterol biosynthesis by Fusaria. This paper reports on the production of phenolic acids by Fusaria for the first time.

  10. trans-Cinnamic and Chlorogenic Acids Affect the Secondary Metabolic Profiles and Ergosterol Biosynthesis by Fusarium culmorum and F. graminearum Sensu Stricto

    PubMed Central

    Kulik, Tomasz; Stuper-Szablewska, Kinga; Bilska, Katarzyna; Buśko, Maciej; Ostrowska-Kołodziejczak, Anna; Załuski, Dariusz; Perkowski, Juliusz

    2017-01-01

    Plant-derived compounds limiting mycotoxin contamination are currently of major interest in food and feed production. However, their potential application requires an evaluation of their effects on fungal secondary metabolism and membrane effects. In this study, different strains of Fusarium culmorum and F. graminearum sensu stricto were exposed to trans-cinnamic and chlorogenic acids on solid YES media. Fusaria produced phenolic acids, whose accumulation was lowered by exogenous phenolic compounds. In addition, fungi reduced exogenous phenolic acids, leading either to their conversion or degradation. trans-Cinnamic acid was converted to caffeic and ferulic acids, while chlorogenic acid was degraded to caffeic acid. The latter underwent further degradation to protocatechuic acid. Fungal-derived trans-cinnamic acid, as the first intermediate of the shikimate pathway, increased after chlorogenic acid treatment, presumably due to the further inhibition of the conversion of trans-cinnamic acid. Exogenous trans-cinnamic and chlorogenic acid displayed the inhibition of mycotoxin production by Fusaria, which appeared to be largely dependent on the phenolic compound and its concentration and the assayed strain. Exogenous phenolic acids showed different effects on ergosterol biosynthesis by fungi. It was found that the production of this membrane sterol was stimulated by trans-cinnamic acid, while chlorogenic acid negatively impacted ergosterol biosynthesis, suggesting that phenolic acids with stronger antifungal activities may upregulate ergosterol biosynthesis by Fusaria. This paper reports on the production of phenolic acids by Fusaria for the first time. PMID:28640190

  11. Lack of insecticidal effect of mosquito coils containing either metofluthrin or esbiothrin on Anopheles gambiae sensu lato mosquitoes.

    PubMed

    Lukwa, Nzira; Chiwade, Tonderai

    2008-12-01

    Use of mosquito coils for personal protection against malaria and mosquito nuisance is advocated under mosquito and malaria control programmes. We performed field studies of mosquito coils containing either metofluthrin or esbiothrin in experimental huts situated in Kamhororo village, Gokwe district, Zimbabwe. All tests were performed on 3-5 day old reared female Anopheles gambiae sensu lato mosquitoes. The burning times were 9hr 20min for mosquito coils containing metofluthrin and 8 hr for those containing esbiothrin and the results were significantly different (p = <0.001). The mean knock down rate for mosquito coils containing metofluthrin was 90% and that for esbiothrin was 73.3% and the results were significantly different (p = 0.00). Mosquito coils containing metofluthrin had a mean repellence of 92.7% as compared to 85.4% for esbiothrin and the results were not significantly different (p=0.27). The protection time as required by EPA (1999) was 6 hr for mosquito coils containing metofluthrin and 5 hr for those containing esbiothrin. The mean insecticidal effect of mosquito coils containing metofluthrin was 84% as compared to 83% for those containing esbiothrin and the results were not significantly different (p = 0.56). Both mosquito formulations could not be classified as having insecticidal effect since none of them met the 95% mortality rate criteria.

  12. Molecular characterization and comparison of four Anisakis allergens between Anisakis simplex sensu stricto and Anisakis pegreffii from Japan.

    PubMed

    Quiazon, Karl Marx A; Zenke, Kosuke; Yoshinaga, Tomoyoshi

    2013-07-01

    It remains unclear whether allergens are the same among the sibling species of Anisakis simplex sensu lato. This study was carried out to compare the amino acid sequences of three major (Ani s 1, 2 and 12) and one minor (Ani s 9) Anisakis allergens between A. simplex s.s. and Anisakis pegreffii. We found 2 (out of 163), 1 (out of 869), and 29 (out of 266) amino acid variable sites for Ani s 1, 2, and 12, respectively. However, as both intra- and inter-species variations were present at the same amino acid positions, no amino acid variations clearly distinguished the two sibling species. IgE-binding epitopes (Ani s 1) and a binding motif of human leukocyte antigen (Ani s 2 and 9) demonstrated by previous studies were conserved. The similarities of the amino acid sequences of the allergens indicate possible similar allergy-associated health risks in humans infected with or accidentally ingesting either Anisakis species. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Genetic Diversity of Borrelia burgdorferi Sensu Stricto in Peromyscus leucopus, the Primary Reservoir of Lyme Disease in a Region of Endemicity in Southern Maryland

    PubMed Central

    Anderson, Jennifer M.; Norris, Douglas E.

    2006-01-01

    In the north central and northeastern United States, Borrelia burgdorferi sensu stricto, the etiologic agent of Lyme disease (LD), is maintained in an enzootic cycle between the vector, Ixodes scapularis, and the primary reservoir host, Peromyscus leucopus. Genetic diversity of the pathogen based on sequencing of two plasmid-located genes, those for outer surface protein A (ospA) and outer surface protein C (ospC), has been examined in both tick and human specimens at local, regional, and worldwide population scales. Additionally, previous studies have only been conducted with tick or human specimens at the local population level in areas with high LD transmission rates. This study examined the genetic diversity of circulating borreliae in the reservoir population from a large region of the western coastal plains of southern Maryland, where moderate numbers of human LD cases are reported. Six ospA mobility classes, including two that were not previously described, and eight ospC groups were found among the P. leucopus samples. Twenty-five percent of all specimens were infected with more than one ospA or ospC variant. The frequency distribution of variants was homogeneous, both locally and spatially. The spirochete diversity found in Maryland was not as high as that observed among northern tick populations, yet similar genotypes were observed in both populations. These results also show that mice are important for maintaining Borrelia variants, even rare variants, and that reservoir populations should therefore be considered when assessing the diversity of B. burgdorferi. PMID:16885284

  14. Characterization of virulence profile, protein secretion and immunogenicity of different Sporothrix schenckii sensu stricto isolates compared with S. globosa and S. brasiliensis species

    PubMed Central

    Fernandes, Geisa Ferreira; dos Santos, Priscila Oliveira; Rodrigues, Anderson Messias; Sasaki, Alexandre Augusto; Burger, Eva; de Camargo, Zoilo Pires

    2013-01-01

    A comparative study about protein secretion, immunogenicity and virulence was performed in order to characterize and to compare eight Sporothrix schenckii sensu stricto isolates. For virulence characterization, a murine model, based on survival assay and CFU counting was used. S. brasiliensis and S. globosa, a highly virulent and a non-virulent isolates, respectively were used as external controls. Exoantigen profiles showed different secreted molecules; the 46- and 60-kDa molecules were commonly secreted by all three species. The S. schenckii s. str. isolates could be classified as non-virulent or presenting low, medium or high virulence, based on survival times after infection and recovery of viable fungi. The humoral response profiles of mice infected with S. schenckii s. str., S. globosa and S. brasiliensis were heterogeneous; five virulent isolates (S. schenckii s. str., n = 4 and S. brasiliensis, n = 1) had in common the recognition of the 60-kDa molecule by their respective antisera, suggesting that this antigen may be involved in virulence. Furthermore, the 110-kDa molecule was secreted and recognized by antisera from four virulent isolates (S. schenckii s. str., n = 3 and S. brasiliensis, n = 1), so there is a possibility that this molecule is also related to virulence. Our findings reveal different degrees of virulence in S. schenckii s. str. isolates and suggest the correlation of protein secretion and immunogenicity with virulence of S. schenckii complex. These findings provide new insights into the pathogenesis of S. schenckii s. str. and improve the knowledge about immunogenicity and protein profiles in S. schenckii complex. PMID:23324498

  15. Mitochondrial DNA-inferred population structure and demographic history of the mitten crab (Eriocheir sensu stricto) found along the coast of mainland China.

    PubMed

    Wang, Chenghui; Li, Chenhong; Li, Sifa

    2008-08-01

    The mitten crab, Eriocheir sensu stricto, is economically important in East Asia, although it is an invasive species in Europe and North America. Little is known about its population structure and historical demography in its native range, especially along the Pacific coast of China. We collected mitochondrial cytochrome oxidase subunit II and cytochrome b sequences from 154 individuals distributed in the rivers along the Chinese coast and 15 individuals from Japan. Phylogenetic analysis resulted in three major monophyletic groups: northern China, southern China and Japan. Negligible migration was detected among those groups by coalescent analysis. Hence, we support the recognition of three species: Eriocheir hepuensis in southern China, Eriocheir sinensis in northern China and Eriocheir japonica in Japan. The populations in the middle (the Oujiang and Minjiang Rivers) possess a mixture of haplotypes similar to either the northern or the southern haplotypes. We believe that secondary intergradation as the most likely cause of the clinal variation based on examining the genetic variation in the latitudinal space. The estimated divergence time between E. sinensis and E. hepuensis is 2.24 million years ago (Ma), while the divergence time between E. japonica and E. sinensis is 1.83 Ma. Both are in the late Pliocene, suggesting that land bridges associated with low sea level during that time might have severed as vicariant barriers for speciation. The divergence of the northern population and the 'northern haplotypes' in the middle population was estimated at 0.12 Ma, while the time separating the southern population and the 'southern haplotypes' in the middle populations was estimated as 0.16 Ma, implicating possible secondary contact in the late Pleistocene.

  16. Dose–response tests and semi-field evaluation of lethal and sub-lethal effects of slow release pyriproxyfen granules (Sumilarv®0.5G) for the control of the malaria vectors Anopheles gambiae sensu lato

    PubMed Central

    2013-01-01

    Background Recently research has shown that larviciding can be an effective tool for integrated malaria vector control. Nevertheless, the uptake of this intervention has been hampered by the need to re-apply larvicides frequently. There is a need to explore persistent, environmentally friendly larvicides for malaria vector control to reduce intervention efforts and costs by reducing the frequency of application. In this study, the efficacy of a 0.5% pyriproxyfen granule (Surmilarv®0.5G, Sumitomo Chemicals) was assessed for the control of Anopheles gambiae sensu stricto and Anopheles arabiensis, the major malaria vectors in sub-Saharan Africa. Methods Dose–response and standardized field tests were implemented following standard procedures of the World Health Organization’s Pesticide Evaluation Scheme to determine: (i) the susceptibility of vectors to this formulation; (ii) the residual activity and appropriate retreatment schedule for field application; and, (iii) sub-lethal impacts on the number and viability of eggs laid by adults after exposure to Sumilarv®0.5G during larval development. Results Anopheles gambiae s.s. and An. arabiensis were highly susceptible to Sumilarv®0.5G. Estimated emergence inhibition (EI) values were very low and similar for both species. The minimum dosage that completely inhibited adult emergence was between 0.01-0.03 parts per million (ppm) active ingredient (ai). Compared to the untreated control, an application of 0.018 ppm ai prevented 85% (95% confidence interval (CI) 82%-88%) of adult emergence over six weeks under standardized field conditions. A fivefold increase in dosage of 0.09 ppm ai prevented 97% (95% CI 94%-98%) emergence. Significant sub-lethal effects were observed in the standardized field tests. Female An. gambiae s.s. that were exposed to 0.018 ppm ai as larvae laid 47% less eggs, and females exposed to 0.09 ppm ai laid 74% less eggs than females that were unexposed to the treatment. Furthermore, 77

  17. Biting patterns and seasonality of anopheles gambiae sensu lato and anopheles funestus mosquitoes in Kamuli District, Uganda

    PubMed Central

    2013-01-01

    Background We investigated the biting patterns and seasonal abundances of Anopheles gambiae s.l. and An. funestus mosquitoes in Kamuli District, Uganda. Methods Hourly indoor and outdoor catches of human biting mosquitoes were sampled from 19.00 to 07.00 hours for four consecutive nights each month using bed net traps in forty-eight houses randomly selected from Bugabula county where insecticide-treated bed nets (ITNs) had been used for at least five years and Budiope county where ITNs had not been used. The indoor and outdoor human-biting fractions, time of biting of the anophelines and climatic data were recorded from January to December 2010. Data were analysed using Multi-way analysis of variance, Kruskal-wallis rank sum test and Pearson correlation. The number of mosquitoes caught biting humans and resting indoors, the indoor and outdoor human biting densities and biting rates during different hours of the night, and mosquito abundances for a twelve-month sampling period in both zones are reported. Results Approximately four times more Anopheles mosquitoes were caught biting humans in Budiope County than in the Bugabula zone, with An. gambiae s. l. catches exceeding those of An. funestus. In both zones, peak night biting occurred between 23.00 and 05.00 hours. The majority of bites occurred between 03.00 and 06.00 hours for both Anopheles gambiae s. l. and funestus group. Outdoor biting densities of Anopheles gambiae s. l. exceeded the indoor biting densities throughout the night in both zones, while the indoor and outdoor human biting densities of An. funestus group were apparently equal. The outdoor and indoor human biting rates were similar in both zones. In Bugabula county, the abundance of An. gambiae s.l. was rainfall-dependent, while the An. funestus group could thrive with or without rain fall. In Budiope county, both An. gambiae s.l. and An. funestus mosquitoes thrived all year round regardless of the amount of rainfall. Conclusion Considering the

  18. Review of Apanteles sensu stricto (Hymenoptera, Braconidae, Microgastrinae) from Area de Conservación Guanacaste, northwestern Costa Rica, with keys to all described species from Mesoamerica

    PubMed Central

    Fernández-Triana, Jose L.; Whitfield, James B.; Rodriguez, Josephine J.; Smith, M. Alex; Janzen, Daniel H.; Hallwachs, Winnie D.; Hajibabaei, Mehrdad; Burns, John M.; Solis, M. Alma; Brown, John; Cardinal, Sophie; Goulet, Henri; Hebert, Paul D. N.

    2014-01-01

    Abstract More than half a million specimens of wild-caught Lepidoptera caterpillars have been reared for their parasitoids, identified, and DNA barcoded over a period of 34 years (and ongoing) from Area de Conservación de Guanacaste (ACG), northwestern Costa Rica. This provides the world’s best location-based dataset for studying the taxonomy and host relationships of caterpillar parasitoids. Among Hymenoptera, Microgastrinae (Braconidae) is the most diverse and commonly encountered parasitoid subfamily, with many hundreds of species delineated to date, almost all undescribed. Here, we reassess the limits of the genus Apanteles sensu stricto, describe 186 new species from 3,200+ parasitized caterpillars of hundreds of ACG Lepidoptera species, and provide keys to all 205 described Apanteles from Mesoamerica – including 19 previously described species in addition to the new species. The Mesoamerican Apanteles are assigned to 32 species-groups, all but two of which are newly defined. Taxonomic keys are presented in two formats: traditional dichotomous print versions and links to electronic interactive versions (software Lucid 3.5). Numerous illustrations, computer-generated descriptions, distributional information, wasp biology, and DNA barcodes (where available) are presented for every species. All morphological terms are detailed and linked to the Hymenoptera Anatomy Ontology website. DNA barcodes (a standard fragment of the cytochrome c oxidase I (COI) mitochondrial gene), information on wasp biology (host records, solitary/gregariousness of wasp larvae), ratios of morphological features, and wasp microecological distributions were used to help clarify boundaries between morphologically cryptic species within species-complexes. Because of the high accuracy of host identification for about 80% of the wasp species studied, it was possible to analyze host relationships at a regional level. The ACG species of Apanteles attack mainly species of Hesperiidae

  19. Review of Apanteles sensu stricto (Hymenoptera, Braconidae, Microgastrinae) from Area de Conservación Guanacaste, northwestern Costa Rica, with keys to all described species from Mesoamerica.

    PubMed

    Fernández-Triana, Jose L; Whitfield, James B; Rodriguez, Josephine J; Smith, M Alex; Janzen, Daniel H; Hallwachs, Winnie D; Hajibabaei, Mehrdad; Burns, John M; Solis, M Alma; Brown, John; Cardinal, Sophie; Goulet, Henri; Hebert, Paul D N

    2014-01-01

    More than half a million specimens of wild-caught Lepidoptera caterpillars have been reared for their parasitoids, identified, and DNA barcoded over a period of 34 years (and ongoing) from Area de Conservación de Guanacaste (ACG), northwestern Costa Rica. This provides the world's best location-based dataset for studying the taxonomy and host relationships of caterpillar parasitoids. Among Hymenoptera, Microgastrinae (Braconidae) is the most diverse and commonly encountered parasitoid subfamily, with many hundreds of species delineated to date, almost all undescribed. Here, we reassess the limits of the genus Apanteles sensu stricto, describe 186 new species from 3,200+ parasitized caterpillars of hundreds of ACG Lepidoptera species, and provide keys to all 205 described Apanteles from Mesoamerica - including 19 previously described species in addition to the new species. The Mesoamerican Apanteles are assigned to 32 species-groups, all but two of which are newly defined. Taxonomic keys are presented in two formats: traditional dichotomous print versions and links to electronic interactive versions (software Lucid 3.5). Numerous illustrations, computer-generated descriptions, distributional information, wasp biology, and DNA barcodes (where available) are presented for every species. All morphological terms are detailed and linked to the Hymenoptera Anatomy Ontology website. DNA barcodes (a standard fragment of the cytochrome c oxidase I (COI) mitochondrial gene), information on wasp biology (host records, solitary/gregariousness of wasp larvae), ratios of morphological features, and wasp microecological distributions were used to help clarify boundaries between morphologically cryptic species within species-complexes. Because of the high accuracy of host identification for about 80% of the wasp species studied, it was possible to analyze host relationships at a regional level. The ACG species of Apanteles attack mainly species of Hesperiidae, Elachistidae and

  20. Localized breeding of the Anopheles gambiae complex (Diptera: Culicidae) along the River Gambia, West Africa.

    PubMed

    Bøgh, C; Bøgh, C; Clarke, S E; Jawara, M; Thomas, C J; Lindsay, S W

    2003-08-01

    A study was undertaken to identify the major larval habitats of the Anopheles gambiae (Giles) complex in rural Gambia. Mosquito larvae and pupae were sampled along transects and in specific habitats in the central region of the country during the rainy seasons of 1996 and 1997. The sampling showed that the major breeding sites were located on the flooded alluvial soils bordering the river. The largest numbers of larvae were found during September, one month after the peak rains. Polymerase chain reaction analysis of specimens showed that Anopheles melas (Theobald) was the dominant species in the flooded areas (81.5%), followed by A. gambiae sensu stricto (Giles) (18.0%) and A. arabiensis (Patton) (0.5%). By sampling in specific habitats it was evident that A. arabiensis was mainly breeding in rain-fed rice fields along the edge of the alluvial soils. Anopheles melas and A. gambiae s.s. often coexisted but whereas A. melas were found in water with a salinity of up to 72% sea water (25.2 g NaCl l(-1)), A. gambiae s.s. only occurred in water with up to 30% sea water (10.5 g NaCl l(-1)). Anopheles melas larvae were found in association with plant communities dominated by sedges and grasses (Eleocharis sp., Paspalum sp., Sporobolus sp.) and sea-purslane Sesuvium portulacastrum (L.) and the presence of cattle hoof prints, whereas A. gambiae s.s. larvae mainly occurred in association with Paspalum sp. and Eleocharis sp. The study showed that even during the peak rainy season, breeding of the A. gambiae complex is almost entirely restricted to the extensive alluvial areas along the river.

  1. Characterisation of Species and Diversity of Anopheles gambiae Keele Colony

    PubMed Central

    McGeechan, Sion; Inch, Donald; Smart, Graeme; Richterová, Lenka; Mwangi, Jonathan M.

    2016-01-01

    Anopheles gambiae sensu stricto was recently reclassified as two species, An. coluzzii and An. gambiae s.s., in wild-caught mosquitoes, on the basis of the molecular form, denoted M or S, of a marker on the X chromosome. The An. gambiae Keele line is an outbred laboratory colony strain that was developed around 12 years ago by crosses between mosquitoes from 4 existing An. gambiae colonies. Laboratory colonies of mosquitoes often have limited genetic diversity because of small starting populations (founder effect) and subsequent fluctuations in colony size. Here we describe the characterisation of the chromosomal form(s) present in the Keele line, and investigate the diversity present in the colony using microsatellite markers on chromosome 3. We also characterise the large 2La inversion on chromosome 2. The results indicate that only the M-form of the chromosome X marker is present in the Keele colony, which was unexpected given that 3 of the 4 parent colonies were probably S-form. Levels of diversity were relatively high, as indicated by a mean number of microsatellite alleles of 6.25 across 4 microsatellites, in at least 25 mosquitoes. Both karyotypes of the inversion on chromosome 2 (2La/2L+a) were found to be present at approximately equal proportions. The Keele colony has a mixed M- and S-form origin, and in common with the PEST strain, we propose continuing to denote it as an An. gambiae s.s. line. PMID:28033418

  2. Phylogenetic relationships in Taxodiaceae and Cupressaceae sensu stricto based on matK gene, chlL gene, trnL-trnF IGS region, and trnL intron sequences.

    PubMed

    Kusumi, J; Tsumura, Y; Yoshimaru, H; Tachida, H

    2000-10-01

    Nucleotide sequences from four chloroplast genes, the matK, chlL, intergenic spacer (IGS) region between trnL and trnF, and an intron of trnL, were determined from all species of Taxodiaceae and five species of Cupressaceae sensu stricto (s.s.). Phylogenetic trees were constructed using the maximum parsimony and the neighbor-joining methods with Cunninghamia as an outgroup. These analyses provided greater resolution of relationships among genera and higher bootstrap supports for clades compared to previous analyses. Results indicate that Taiwania diverged first, and then Athrotaxis diverged from the remaining genera. Metasequoia, Sequoia, and Sequoiadendron form a clade. Taxodium and Glyptostrobus form a clade, which is the sister to Cryptomeria. Cupressaceae s.s. are derived from within Taxodiaceae, being the most closely related to the Cryptomeria/Taxodium/Glyptostrobus clade. These relationships are consistent with previous morphological groupings and the analyses of molecular data. In addition, we found acceleration of evolutionary rates in Cupressaceae s.s. Possible causes for the acceleration are discussed.

  3. Nitrate affects sensu-stricto germination of after-ripened Sisymbrium officinale seeds by modifying expression of SoNCED5, SoCYP707A2 and SoGA3ox2 genes.

    PubMed

    Carrillo-Barral, Néstor; Matilla, Angel J; Rodríguez-Gacio, María del Carmen; Iglesias-Fernández, Raquel

    2014-03-01

    The influence of nitrate upon the germination of Sisymbrium officinale seeds is not entirely controlled by after-ripening (AR), a process clearly influenced by nitrate. Recently, we have reported that nitrate affects sensu-stricto germination of non-AR (AR0) seeds by modifying the expression of crucial genes involved in the metabolism of GA and ABA. In this study, we demonstrate that nitrate affects also the germination of AR seeds because: (i) the AR negatively alters the ABA sensitivity being the seed more ABA-sensible as the AR is farthest from optimal (AR0 and AR20 versus AR7); in the presence of diniconazole (DZ), a competitive inhibitor of ABA 8'-hydroxylase, testa rupture is affected while the endosperm rupture is not. (ii) AR7 seed-coat rupture is not inhibited by paclobutrazol (PBZ) suggesting that nitrate can act by a mechanism GA-independent. (iii) The germination process is accelerated by nitrate, most probably by the increase in the expression of SoNCED5, SoCYP707A2 and SoGA3ox2 genes. Taken together, these and previous results demonstrate that nitrate promotes germination of AR and non-AR seeds through transcriptional changes of different genes involved in ABA and GA metabolism.

  4. Detection of Borrelia burgdorferi Sensu Stricto ospC Alleles Associated with Human Lyme Borreliosis Worldwide in Non-Human-Biting Tick Ixodes affinis and Rodent Hosts in Southeastern United States

    PubMed Central

    Golovchenko, Maryna; Hönig, Václav; Mallátová, Nadja; Krbková, Lenka; Mikulášek, Peter; Fedorova, Natalia; Belfiore, Natalia M.; Grubhoffer, Libor; Lane, Robert S.; Oliver, James H.

    2013-01-01

    Comparative analysis of ospC genes from 127 Borrelia burgdorferi sensu stricto strains collected in European and North American regions where Lyme disease is endemic and where it is not endemic revealed a close relatedness of geographically distinct populations. ospC alleles A, B, and L were detected on both continents in vectors and hosts, including humans. Six ospC alleles, A, B, L, Q, R, and V, were prevalent in Europe; 4 of them were detected in samples of human origin. Ten ospC alleles, A, B, D, E3, F, G, H, H3, I3, and M, were identified in the far-western United States. Four ospC alleles, B, G, H, and L, were abundant in the southeastern United States. Here we present the first expanded analysis of ospC alleles of B. burgdorferi strains from the southeastern United States with respect to their relatedness to strains from other North American and European localities. We demonstrate that ospC genotypes commonly associated with human Lyme disease in European and North American regions where the disease is endemic were detected in B. burgdorferi strains isolated from the non-human-biting tick Ixodes affinis and rodent hosts in the southeastern United States. We discovered that some ospC alleles previously known only from Europe are widely distributed in the southeastern United States, a finding that confirms the hypothesis of transoceanic migration of Borrelia species. PMID:23263953

  5. Hybridization studies to modify the host preference of Anopheles gambiae.

    PubMed

    Pates, H V; Curtis, C F; Takken, W

    2014-08-01

    A strategy to decrease the vector competence of Anopheles gambiae sensu stricto (Diptera: Culicidae), the most efficient malaria vector in Africa, may consist of exploiting the genes involved in zoophily. Crossing and backcrossing experiments were performed between An. gambiae s.s. and the zoophilic sibling species Anopheles quadriannulatus. Mosquito strains were tested in a dual-choice olfactometer to investigate their responses to cow odour. Totals of 12% of An. gambiae s.s. and 59% of An. quadriannulatus selected the port with the cow odour. Crosses and backcrosses did not show a significant preference for the cow-baited port. The results indicated that anthropophilic behaviour in An. gambiae s.s. is a dominant or partially dominant trait, which, in conjunction with the unstable zoophilic behaviour observed in An. quadriannulatus, poses a serious obstacle to plans to decrease vector competence by modifying the anthropophilic trait. © 2014 The Royal Entomological Society.

  6. Loop-Mediated Isothermal Amplification (LAMP) for Rapid Identification of Anopheles gambiae and Anopheles arabiensis Mosquitoes

    PubMed Central

    Bonizzoni, Mariangela; Afrane, Yaw; Yan, Guiyun

    2013-01-01

    The main malaria vectors of sub-Saharan Africa, Anopheles gambiae sensu stricto and Anopheles arabiensis are morphologically indistinguishable, but often occur in sympatry and differ in feeding preference and vector competence. It is important to assess vector species identity for understanding the vectorial system and establishing appropriate vector control measures. The currently available species diagnosis methods for An. gambiae sensu latu require equipment to which public health practitioners in many African countries may not have access. This report describes a loop-mediated isothermal amplification technique (LAMP) for An. gambiae species diagnosis. The LAMP method was tested in single mosquito legs and whole body. The sensitivity and specificity of the LAMP method, in reference to the conventional rDNA-polymerse chain reaction (PCR) method, ranged from 0.93 to 1.00. The LAMP-based species identification method can be performed in a water bath and completed within 65 minutes, representing an alternative method for rapid and field applicable vector species diagnosis. PMID:19996433

  7. Co-occurrence and distribution of East (L1014S) and West (L1014F) African knock-down resistance in Anopheles gambiae sensu lato population of Tanzania

    PubMed Central

    Kabula, Bilali; Kisinza, William; Tungu, Patrick; Ndege, Chacha; Batengana, Benard; Kollo, Douglas; Malima, Robert; Kafuko, Jessica; Mohamed, Mahdi; Magesa, Stephen

    2014-01-01

    Objective Insecticide resistance molecular markers can provide sensitive indicators of resistance development in Anopheles vector populations. Assaying these makers is of paramount importance in the resistance monitoring programme. We investigated the presence and distribution of knock-down resistance (kdr) mutations in Anopheles gambiae s.l. in Tanzania. Methods Indoor-resting Anopheles mosquitoes were collected from 10 sites and tested for insecticide resistance using the standard WHO protocol. Polymerase chain reaction-based molecular diagnostics were used to genotype mosquitoes and detect kdr mutations. Results The An. gambiae tested were resistance to lambdacyhalothrin in Muheza, Arumeru and Muleba. Out of 350 An. gambiae s.l. genotyped, 35% were An. gambiae s.s. and 65% An. arabiensis. L1014S and L1014F mutations were detected in both An. gambiae s.s. and An. arabiensis. L1014S point mutation was found at the allelic frequency of 4–33%, while L1014F was at the allelic frequency 6–41%. The L1014S mutation was much associated with An. gambiae s.s. (χ2 = 23.41; P < 0.0001) and L1014F associated with An. arabiensis (χ2 = 11.21; P = 0.0008). The occurrence of the L1014S allele was significantly associated with lambdacyhalothrin resistance mosquitoes (Fisher exact P < 0.001). Conclusion The observed co-occurrence of L1014S and L1014F mutations coupled with reports of insecticide resistance in the country suggest that pyrethroid resistance is becoming a widespread phenomenon among our malaria vector populations. The presence of L1014F mutation in this East African mosquito population indicates the spreading of this gene across Africa. The potential operational implications of these findings on malaria control need further exploration. Objectif Les marqueurs moléculaires de la résistance aux insecticides peuvent fournir des indicateurs sensibles du développement de la résistance dans les populations de vecteurs Anopheles. Le test de ces

  8. New repellent effective against African malaria mosquito Anopheles gambiae: implications for vector control.

    PubMed

    Hodson, C N; Yu, Y; Plettner, E; Roitberg, B D

    2016-12-01

    Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) is a vector for Plasmodium, the causative agent of malaria. Current control strategies to reduce the impact of malaria focus on reducing the frequency of mosquito attacks on humans, thereby decreasing Plasmodium transmission. A need for new repellents effective against Anopheles mosquitoes has arisen because of changes in vector behaviour as a result of control strategies and concern over the health impacts of current repellents. The response of A. gambiae to potential repellents was investigated through an electroantennogram screen and the most promising of these candidates (1-allyloxy-4-propoxybenzene, 3c{3,6}) chosen for behavioural testing. An assay to evaluate the blood-host seeking behaviour of A. gambiae towards a simulated host protected with this repellent was then performed. The compound 3c{3,6} was shown to be an effective repellent, causing mosquitoes to reduce their contact with a simulated blood-host and probe less at the host odour. Thus, 3c{3,6} may be an effective repellent for the control of A. gambiae. © 2016 The Royal Entomological Society.

  9. Breakdown in the Process of Incipient Speciation in Anopheles gambiae

    PubMed Central

    Nwakanma, Davis C.; Neafsey, Daniel E.; Jawara, Musa; Adiamoh, Majidah; Lund, Emily; Rodrigues, Amabelia; Loua, Kovana M.; Konate, Lassana; Sy, Ngayo; Dia, Ibrahima; Awolola, T. Samson; Muskavitch, Marc A. T.; Conway, David J.

    2013-01-01

    Understanding genetic causes and effects of speciation in sympatric populations of sexually reproducing eukaryotes is challenging, controversial, and of practical importance for controlling rapidly evolving pests and pathogens. The major African malaria vector mosquito Anopheles gambiae sensu stricto (s.s.) is considered to contain two incipient species with strong reproductive isolation, hybrids between the M and S molecular forms being very rare. Following recent observations of higher proportions of hybrid forms at a few sites in West Africa, we conducted new surveys of 12 sites in four contiguous countries (The Gambia, Senegal, Guinea-Bissau, and Republic of Guinea). Identification and genotyping of 3499 A. gambiae s.s. revealed high frequencies of M/S hybrid forms at each site, ranging from 5 to 42%, and a large spectrum of inbreeding coefficient values from 0.11 to 0.76, spanning most of the range expected between the alternative extremes of panmixia and assortative mating. Year-round sampling over 2 years at one of the sites in The Gambia showed that M/S hybrid forms had similar relative frequencies throughout periods of marked seasonal variation in mosquito breeding and abundance. Genome-wide scans with an Affymetrix high-density single-nucleotide polymorphism (SNP) microarray enabled replicate comparisons of pools of different molecular forms, in three separate populations. These showed strong differentiation between M and S forms only in the pericentromeric region of the X chromosome that contains the molecular form-specific marker locus, with only a few other loci showing minor differences. In the X chromosome, the M/S hybrid forms were more differentiated from M than from S forms, supporting a hypothesis of asymmetric introgression and backcrossing. PMID:23335339

  10. Improvement of a synthetic lure for Anopheles gambiae using compounds produced by human skin microbiota.

    PubMed

    Verhulst, Niels O; Mbadi, Phoebe A; Kiss, Gabriella Bukovinszkiné; Mukabana, Wolfgang R; van Loon, Joop J A; Takken, Willem; Smallegange, Renate C

    2011-02-08

    Anopheles gambiae sensu stricto is considered to be highly anthropophilic and volatiles of human origin provide essential cues during its host-seeking behaviour. A synthetic blend of three human-derived volatiles, ammonia, lactic acid and tetradecanoic acid, attracts A. gambiae. In addition, volatiles produced by human skin bacteria are attractive to this mosquito species. The purpose of the current study was to test the effect of ten compounds present in the headspace of human bacteria on the host-seeking process of A. gambiae. The effect of each of the ten compounds on the attractiveness of a basic blend of ammonia, lactic and tetradecanoic acid to A. gambiae was examined. The host-seeking response of A. gambiae was evaluated in a laboratory set-up using a dual-port olfactometer and in a semi-field facility in Kenya using MM-X traps. Odorants were released from LDPE sachets and placed inside the olfactometer as well as in the MM-X traps. Carbon dioxide was added in the semi-field experiments, provided from pressurized cylinders or fermenting yeast. The olfactometer and semi-field set-up allowed for high-throughput testing of the compounds in blends and in multiple concentrations. Compounds with an attractive or inhibitory effect were identified in both bioassays. 3-Methyl-1-butanol was the best attractant in both set-ups and increased the attractiveness of the basic blend up to three times. 2-Phenylethanol reduced the attractiveness of the basic blend in both bioassays by more than 50%. Identification of volatiles released by human skin bacteria led to the discovery of compounds that have an impact on the host-seeking behaviour of A. gambiae. 3-Methyl-1-butanol may be used to increase mosquito trap catches, whereas 2-phenylethanol has potential as a spatial repellent. These two compounds could be applied in push-pull strategies to reduce mosquito numbers in malaria endemic areas.

  11. Oviposition by African malaria vector mosquitoes. II. Effects of site tone, water type and conspecific immatures on target selection by freshwater Anopheles gambiae Giles, sensu lato.

    PubMed

    McCrae, A W

    1984-06-01

    Females of Anopheles gambiae s. lat., most of which would have been A. gambiae s. str., were collected from houses in coastal Kenya and tested for their oviposition preferences using Petri dishes in large laboratory cages with lighting equivalent to weak moonlight. Significantly more eggs were laid overnight in water over black than over paler tones, and this difference increased as contrast with the surrounding floor was increased. Direct observation revealed that over white targets, females oviposited from a settled posture, whereas over black targets they did so from flight. The influence on this behaviour of target darkness (tone) overrode that of cage size or target size. In tests which yielded markedly fewer eggs in sea water than in tap water, no significant difference was detected when cage floors were either black or white, although a black floor might have resulted in significantly greater discrimination against sea water had more tests been conducted. All further testing was done over black cage floors. Turbid water from a natural development site received more eggs than distilled, tap or swamp water, even though the turbid water appeared paler than the others. The females did not discriminate between rearing water and tap water, or tap water with and without pupae, but the presence of larvae was repellent. Turbid water from a development site thus seemed to possess an arrestant property which overrode selection favouring darker targets, and which was not derived from prior presence of conspecific immatures. It is suggested that for A. gambiae, oviposition from a settled posture is a response to sub-optimal stimuli, possibly indicating conditions under which oviposition would not occur in nature, and hence why cage experiments using white targets have in the past yielded confusing results.

  12. Geographic population structure of the African malaria vector Anopheles gambiae suggests a role for the forest-savannah biome transition as a barrier to gene flow

    PubMed Central

    Pinto, J; Egyir-Yawson, A; Vicente, JL; Gomes, B; Santolamazza, F; Moreno, M; Charlwood, JD; Simard, F; Elissa, N; Weetman, D; Donnelly, MJ; Caccone, A; della Torre, A

    2013-01-01

    The primary Afrotropical malaria mosquito vector Anopheles gambiae sensu stricto has a complex population structure. In west Africa, this species is split into two molecular forms and displays local and regional variation in chromosomal arrangements and behaviors. To investigate patterns of macrogeographic population substructure, 25 An. gambiae samples from 12 African countries were genotyped at 13 microsatellite loci. This analysis detected the presence of additional population structuring, with the M-form being subdivided into distinct west, central, and southern African genetic clusters. These clusters are coincident with the central African rainforest belt and northern and southern savannah biomes, which suggests restrictions to gene flow associated with the transition between these biomes. By contrast, geographically patterned population substructure appears much weaker within the S-form. PMID:24062800

  13. Geographic population structure of the African malaria vector Anopheles gambiae suggests a role for the forest-savannah biome transition as a barrier to gene flow.

    PubMed

    Pinto, J; Egyir-Yawson, A; Vicente, Jl; Gomes, B; Santolamazza, F; Moreno, M; Charlwood, Jd; Simard, F; Elissa, N; Weetman, D; Donnelly, Mj; Caccone, A; Della Torre, A

    2013-09-01

    The primary Afrotropical malaria mosquito vector Anopheles gambiae sensu stricto has a complex population structure. In west Africa, this species is split into two molecular forms and displays local and regional variation in chromosomal arrangements and behaviors. To investigate patterns of macrogeographic population substructure, 25 An. gambiae samples from 12 African countries were genotyped at 13 microsatellite loci. This analysis detected the presence of additional population structuring, with the M-form being subdivided into distinct west, central, and southern African genetic clusters. These clusters are coincident with the central African rainforest belt and northern and southern savannah biomes, which suggests restrictions to gene flow associated with the transition between these biomes. By contrast, geographically patterned population substructure appears much weaker within the S-form.

  14. Reproductive Isolation among Sympatric Molecular Forms of An. gambiae from Inland Areas of South-Eastern Senegal

    PubMed Central

    Niang, El Hadji Amadou; Konaté, Lassana; Diallo, Mawlouth; Faye, Ousmane; Dia, Ibrahima

    2014-01-01

    The Anopheles gambiae species complex includes at least seven morphologically indistinguishable species, one of which, Anopheles gambiae sensu stricto, is the primary mosquito vector responsible for the transmission of malaria across sub-Saharan Africa. Sympatric ecological diversification of An. gambiae s.s. is in progress within this complex, leading to the emergence of at least two incipient species (the M and S molecular forms now recognized as good species and named An. coluzzii and An. gambiae respectively) that show heterogeneous levels of divergence in most parts of Africa. However, this process seems to have broken down in coastal areas of West Africa at the extreme edge of the distribution. We undertook a longitudinal study to describe An. gambiae s.s. populations collected from two inland transects with different ecological characteristics in south-eastern Senegal. Analysis of samples collected from 20 sites across these two transects showed the M and S molecular forms coexisted at almost all sampled sites. Overall, similar hybridization rates (2.16% and 1.86%) were recorded in the two transects; sites with relatively high frequencies of M/S hybrids (up to 7%) were clustered toward the north-western part of both transects, often near urban settings. Estimated inbreeding indices for this putative speciation event varied spatially (range: 0.52–1), with hybridization rates being generally lower than expected under panmictic conditions. Such observations suggest substantial reproductive isolation between the M and S molecular forms, and further support the ongoing process of speciation in these inland areas. According to a recent reclassification of the An. gambiae complex, the M and S molecular forms from this zone correspond to An. coluzzii and An. gambiae, respectively. There is considerable evidence that these molecular forms differ in their behavioural and ecological characteristics. Detailed study of these characteristics will allow the development

  15. Molecular evolution and population genetics of a Gram-negative binding protein gene in the malaria vector Anopheles gambiae (sensu lato).

    PubMed

    Salgueiro, Patrícia; Lopes, Ana Sofia; Mendes, Cristina; Charlwood, Jacques Derek; Arez, Ana Paula; Pinto, João; Silveira, Henrique

    2016-09-23

    Clarifying the role of the innate immune system of the malaria vector Anopheles gambiae is a potential way to block the development of the Plasmodium parasites. Pathogen recognition is the first step of innate immune response, where pattern recognition proteins like GNBPs play a central role. We analysed 70 sequences of the protein coding gene GNBPB2 from two species, Anopheles gambiae (s.s.) and An. coluzzii, collected in six African countries. We detected 135 segregating sites defining 63 distinct haplotypes and 30 proteins. Mean nucleotide diversity (π) was 0.014 for both species. We found no significant genetic differentiation between species, but a significant positive correlation between genetic differentiation and geographical distance among populations. Species status seems to contribute less for the molecular differentiation in GNBPB2 than geographical region in the African continent (West and East). Purifying selection was found to be the most common form of selection, as in many other immunity-related genes. Diversifying selection may be also operating in the GNBPB2 gene.

  16. Equivalent susceptibility of Anopheles gambiae M and S molecular forms and Anopheles arabiensis to Plasmodium falciparum infection in Burkina Faso.

    PubMed

    Gnémé, Awa; Guelbéogo, Wamdaogo M; Riehle, Michelle M; Sanou, Antoine; Traoré, Alphonse; Zongo, Soumanaba; Eiglmeier, Karin; Kabré, Gustave B; Sagnon, N'Falé; Vernick, Kenneth D

    2013-06-14

    The Anopheles gambiae sensu lato (s.l.) species complex in Burkina Faso consists of Anopheles arabiensis, and molecular forms M and S of Anopheles gambiae sensu stricto (s.s.). Previous studies comparing the M and S forms for level of infection with Plasmodium falciparum have yielded conflicting results. Mosquito larvae were sampled from natural pools, reared to adulthood under controlled conditions, and challenged with natural P. falciparum by experimental feeding with blood from gametocyte carriers. Oocyst infection prevalence and intensity was determined one week after infection. DNA from carcasses was genotyped to identify species and molecular form. In total, 7,400 adult mosquitoes grown from wild-caught larvae were challenged with gametocytes in 29 experimental infections spanning four transmission seasons. The overall infection prevalence averaged 40.7% for A. gambiae M form, 41.4% for A. gambiae S form, and 40.1% for A. arabiensis. There was no significant difference in infection prevalence or intensity between the three population groups. Notably, infection experiments in which the population groups were challenged in parallel on the same infective blood displayed less infection difference between population groups, while infections with less balanced composition of population groups had lower statistical power and displayed apparent differences that fluctuated more often from the null average. The study clearly establishes that, at the study site in Burkina Faso, there is no difference in genetic susceptibility to P. falciparum infection between three sympatric population groups of the A. gambiae s.l. complex. Feeding the mosquito groups on the same infective blood meal greatly increases statistical power. Conversely, comparison of the different mosquito groups between, rather than within, infections yields larger apparent difference between mosquito groups, resulting from lower statistical power and greater noise, and could lead to false-positive results

  17. Equivalent susceptibility of Anopheles gambiae M and S molecular forms and Anopheles arabiensis to Plasmodium falciparum infection in Burkina Faso

    PubMed Central

    2013-01-01

    Background The Anopheles gambiae sensu lato (s.l.) species complex in Burkina Faso consists of Anopheles arabiensis, and molecular forms M and S of Anopheles gambiae sensu stricto (s.s.). Previous studies comparing the M and S forms for level of infection with Plasmodium falciparum have yielded conflicting results. Methods Mosquito larvae were sampled from natural pools, reared to adulthood under controlled conditions, and challenged with natural P. falciparum by experimental feeding with blood from gametocyte carriers. Oocyst infection prevalence and intensity was determined one week after infection. DNA from carcasses was genotyped to identify species and molecular form. Results In total, 7,400 adult mosquitoes grown from wild-caught larvae were challenged with gametocytes in 29 experimental infections spanning four transmission seasons. The overall infection prevalence averaged 40.7% for A. gambiae M form, 41.4% for A. gambiae S form, and 40.1% for A. arabiensis. There was no significant difference in infection prevalence or intensity between the three population groups. Notably, infection experiments in which the population groups were challenged in parallel on the same infective blood displayed less infection difference between population groups, while infections with less balanced composition of population groups had lower statistical power and displayed apparent differences that fluctuated more often from the null average. Conclusion The study clearly establishes that, at the study site in Burkina Faso, there is no difference in genetic susceptibility to P. falciparum infection between three sympatric population groups of the A. gambiae s.l. complex. Feeding the mosquito groups on the same infective blood meal greatly increases statistical power. Conversely, comparison of the different mosquito groups between, rather than within, infections yields larger apparent difference between mosquito groups, resulting from lower statistical power and greater noise

  18. 16S rRNA Gene-Based Identification of Midgut Bacteria from Field-Caught Anopheles gambiae Sensu Lato and A. funestus Mosquitoes Reveals New Species Related to Known Insect Symbionts

    PubMed Central

    Lindh, Jenny M.; Terenius, Olle; Faye, Ingrid

    2005-01-01

    Field-collected mosquitoes of the two main malaria vectors in Africa, Anopheles gambiae sensu lato and Anopheles funestus, were screened for their midgut bacterial contents. The midgut from each blood-fed mosquito was screened with two different detection pathways, one culture independent and one culture dependent. Bacterial species determination was achieved by sequence analysis of 16S rRNA genes. Altogether, 16 species from 14 genera were identified, 8 by each method. Interestingly, several of the bacteria identified are related to bacteria known to be symbionts in other insects. One isolate, Nocardia corynebacterioides, is a relative of the symbiont found in the vector for Chagas' disease that has been proven useful as a paratransgenic bacterium. Another isolate is a novel species within the γ-proteobacteria that could not be phylogenetically placed within any of the known orders in the class but is close to a group of insect symbionts. Bacteria representing three intracellular genera were identified, among them the first identifications of Anaplasma species from mosquitoes and a new mosquito-Spiroplasma association. The isolates will be further investigated for their suitability for a paratransgenic Anopheles mosquito. PMID:16269761

  19. 16S rRNA gene-based identification of midgut bacteria from field-caught Anopheles gambiae sensu lato and A. funestus mosquitoes reveals new species related to known insect symbionts.

    PubMed

    Lindh, Jenny M; Terenius, Olle; Faye, Ingrid

    2005-11-01

    Field-collected mosquitoes of the two main malaria vectors in Africa, Anopheles gambiae sensu lato and Anopheles funestus, were screened for their midgut bacterial contents. The midgut from each blood-fed mosquito was screened with two different detection pathways, one culture independent and one culture dependent. Bacterial species determination was achieved by sequence analysis of 16S rRNA genes. Altogether, 16 species from 14 genera were identified, 8 by each method. Interestingly, several of the bacteria identified are related to bacteria known to be symbionts in other insects. One isolate, Nocardia corynebacterioides, is a relative of the symbiont found in the vector for Chagas' disease that has been proven useful as a paratransgenic bacterium. Another isolate is a novel species within the gamma-proteobacteria that could not be phylogenetically placed within any of the known orders in the class but is close to a group of insect symbionts. Bacteria representing three intracellular genera were identified, among them the first identifications of Anaplasma species from mosquitoes and a new mosquito-Spiroplasma association. The isolates will be further investigated for their suitability for a paratransgenic Anopheles mosquito.

  20. Genomic Islands of Speciation in Anopheles gambiae

    PubMed Central

    Hahn, Matthew W; Nuzhdin, Sergey V

    2005-01-01

    The African malaria mosquito, Anopheles gambiae sensu stricto (A. gambiae), provides a unique opportunity to study the evolution of reproductive isolation because it is divided into two sympatric, partially isolated subtaxa known as M form and S form. With the annotated genome of this species now available, high-throughput techniques can be applied to locate and characterize the genomic regions contributing to reproductive isolation. In order to quantify patterns of differentiation within A. gambiae, we hybridized population samples of genomic DNA from each form to Affymetrix GeneChip microarrays. We found that three regions, together encompassing less than 2.8 Mb, are the only locations where the M and S forms are significantly differentiated. Two of these regions are adjacent to centromeres, on Chromosomes 2L and X, and contain 50 and 12 predicted genes, respectively. Sequenced loci in these regions contain fixed differences between forms and no shared polymorphisms, while no fixed differences were found at nearby control loci. The third region, on Chromosome 2R, contains only five predicted genes; fixed differences in this region were also verified by direct sequencing. These “speciation islands” remain differentiated despite considerable gene flow, and are therefore expected to contain the genes responsible for reproductive isolation. Much effort has recently been applied to locating the genes and genetic changes responsible for reproductive isolation between species. Though much can be inferred about speciation by studying taxa that have diverged for millions of years, studying differentiation between taxa that are in the early stages of isolation will lead to a clearer view of the number and size of regions involved in the genetics of speciation. Despite appreciable levels of gene flow between the M and S forms of A. gambiae, we were able to isolate three small regions of differentiation where genes responsible for ecological and behavioral isolation are

  1. Insecticide resistance in Anopheles gambiae from south-western Chad, Central Africa

    PubMed Central

    Kerah-Hinzoumbé, Clément; Péka, Mallaye; Nwane, Philippe; Donan-Gouni, Issa; Etang, Josiane; Samè-Ekobo, Albert; Simard, Frédéric

    2008-01-01

    Background Indoor residual spraying and insecticide-treated nets (ITN) are essential components of malaria vector control in Africa. Pyrethroids are the only recommended compounds for nets treatment because they are fast-acting insecticides with low mammalian toxicity. However, there is growing concern that pyrethroid resistance may threaten the sustainability of ITN scaling-up programmes. Here, insecticide susceptibility was investigated in Anopheles gambiae sensu lato from an area of large scale ITN distribution programme in south-western Chad. Methods Susceptibility to 4% DDT, 0.05% deltamethrin, 0.75% permethrin, 0.1% bendiocarb and 5% malathion was assessed using the WHO standard procedures for adult mosquitoes. Tests were carried out with two to four days-old, non-engorged female mosquitoes. The An. gambiae Kisumu strain was used as a reference. Knockdown effect was recorded every 5 min and mortality scored 24 h after exposure. Mosquitoes were identified to species and molecular form by PCR-RFLP and genotypes at the kdr locus were determined in surviving specimens by Hot Oligonucleotide Ligation Assay (HOLA). Results During this survey, full susceptibility to malathion was recorded in all samples. Reduced susceptibility to bendiocarb (mortality rate of 96.1%) was found in one sample out of nine assayed. Increased tolerance to pyrethroids was detected in most samples (8/9) with mortality rates ranging from 70.2 to 96.6% for deltamethrin and from 26.7 to 96.3% for permethrin. Pyrethroid tolerance was not associated with a significant increase of knock-down times. Anopheles arabiensis was the predominant species of the An. gambiae complex in the study area, representing 75 to 100% of the samples. Screening for kdr mutations detected the L1014F mutation in 88.6% (N = 35) of surviving An. gambiae sensu stricto S form mosquitoes. All surviving An. arabiensis (N = 49) and M form An. gambiae s.s. (N = 1) carried the susceptible allele. Conclusion This first

  2. Maternal environment shapes the life history and susceptibility to malaria of Anopheles gambiae mosquitoes.

    PubMed

    Lorenz, Lena M; Koella, Jacob C

    2011-12-21

    It is becoming generally recognized that an individual's phenotype can be shaped not only by its own genotype and environmental experience, but also by its mother's environment and condition. Maternal environmental factors can influence mosquitoes' population dynamics and susceptibility to malaria, and therefore directly and indirectly the epidemiology of malaria. In a full factorial experiment, the effects of two environmental stressors - food availability and infection with the microsporidian parasite Vavraia culicis - of female mosquitoes (Anopheles gambiae sensu stricto) on their offspring's development, survival and susceptibility to malaria were studied. The offspring of A. gambiae s.s. mothers infected with V. culicis developed into adults more slowly than those of uninfected mothers. This effect was exacerbated when mothers were reared on low food. Maternal food availability had no effect on the survival of their offspring up to emergence, and microsporidian infection decreased survival only slightly. Low food availability for mothers increased and V. culicis-infection of mothers decreased the likelihood that the offspring fed on malaria-infected blood harboured malaria parasites (but neither maternal treatment influenced their survival up to dissection). Resource availability and infection with V. culicis of A. gambiae s.s. mosquitoes not only acted as direct environmental stimuli for changes in the success of one generation, but could also lead to maternal effects. Maternal V. culicis infection could make offspring more resistant and less likely to transmit malaria, thus enhancing the efficacy of the microsporidian for the biological control of malaria.

  3. Modelling Anopheles gambiae s.s. Population Dynamics with Temperature- and Age-Dependent Survival

    PubMed Central

    Christiansen-Jucht, Céline; Erguler, Kamil; Shek, Chee Yan; Basáñez, María-Gloria; Parham, Paul E.

    2015-01-01

    Climate change and global warming are emerging as important threats to human health, particularly through the potential increase in vector- and water-borne diseases. Environmental variables are known to affect substantially the population dynamics and abundance of the poikilothermic vectors of disease, but the exact extent of this sensitivity is not well established. Focusing on malaria and its main vector in Africa, Anopheles gambiae sensu stricto, we present a set of novel mathematical models of climate-driven mosquito population dynamics motivated by experimental data suggesting that in An. gambiae, mortality is temperature and age dependent. We compared the performance of these models to that of a “standard” model ignoring age dependence. We used a longitudinal dataset of vector abundance over 36 months in sub-Saharan Africa for comparison between models that incorporate age dependence and one that does not, and observe that age-dependent models consistently fitted the data better than the reference model. This highlights that including age dependence in the vector component of mosquito-borne disease models may be important to predict more reliably disease transmission dynamics. Further data and studies are needed to enable improved fitting, leading to more accurate and informative model predictions for the An. gambiae malaria vector as well as for other disease vectors. PMID:26030468

  4. Modelling Anopheles gambiae s.s. Population Dynamics with Temperature- and Age-Dependent Survival.

    PubMed

    Christiansen-Jucht, Céline; Erguler, Kamil; Shek, Chee Yan; Basáñez, María-Gloria; Parham, Paul E

    2015-05-28

    Climate change and global warming are emerging as important threats to human health, particularly through the potential increase in vector- and water-borne diseases. Environmental variables are known to affect substantially the population dynamics and abundance of the poikilothermic vectors of disease, but the exact extent of this sensitivity is not well established. Focusing on malaria and its main vector in Africa, Anopheles gambiae sensu stricto, we present a set of novel mathematical models of climate-driven mosquito population dynamics motivated by experimental data suggesting that in An. gambiae, mortality is temperature and age dependent. We compared the performance of these models to that of a "standard" model ignoring age dependence. We used a longitudinal dataset of vector abundance over 36 months in sub-Saharan Africa for comparison between models that incorporate age dependence and one that does not, and observe that age-dependent models consistently fitted the data better than the reference model. This highlights that including age dependence in the vector component of mosquito-borne disease models may be important to predict more reliably disease transmission dynamics. Further data and studies are needed to enable improved fitting, leading to more accurate and informative model predictions for the An. gambiae malaria vector as well as for other disease vectors.

  5. Egg hatching, larval movement and larval survival of the malaria vector Anopheles gambiae in desiccating habitats

    PubMed Central

    Koenraadt, Constantianus JM; Paaijmans, Krijn P; Githeko, Andrew K; Knols, Bart GJ; Takken, Willem

    2003-01-01

    Background Although the effects of rainfall on the population dynamics of the malaria vector Anopheles gambiae have been studied in great detail, the effects of dry periods on its survival remain less clear. Methods The effects of drying conditions were simulated by creating desiccated habitats, which consisted of trays filled with damp soil. Experiments were performed in these trays to (i) test the ability of An. gambiae sensu stricto eggs to hatch on damp soil and for larvae to reach an artificial breeding site at different distances of the site of hatching and (ii) to record survival of the four larval stages of An. gambiae s.s. when placed on damp soil. Results Eggs of An. gambiae s.s. hatched on damp soil and emerging larvae were capable of covering a distance of up to 10 cm to reach surface water enabling further development. However, proportions of larvae reaching the site decreased rapidly with increasing distance. First, second and third-instar larvae survived on damp soil for an estimated period of 64, 65 and 69 hrs, respectively. Fourth-instar larvae survived significantly longer and we estimated that the maximum survival time was 113 hrs. Conclusion Short-term survival of aquatic stages of An. gambiae on wet soil may be important and adaptive when considering the transient nature of breeding sites of this species in sub-Saharan Africa. In addition, the results suggest that, for larval vector control methods to be effective, habitats should remain drained for at least 5 days to kill all larvae (e.g. in rice fields) and habitats that recently dried up should be treated as well, if larvicidal agents are applied. PMID:12919636

  6. Responses of adult mosquitoes of two sibling species, Anopheles arabiensis and A. gambiae s.s. (Diptera: Culicidae), to high temperatures.

    PubMed

    Kirby, M J; Lindsay, S W

    2004-10-01

    It is well known that amongst the sibling species of the Anopheles gambiae complex, A. arabiensis Patton predominates over A. gambiae sensu stricto Giles in hotter, drier parts of Africa. Here it was investigated whether A. arabiensis is better adapted to higher temperatures than A. gambiae s.s. at the microclimatic level. Bioassays were used to assess behavioural avoidance activity of adult mosquitoes in the presence of increasing temperature. Female mosquitoes were introduced into a holding tube from which they could escape into a cage through a one-way funnel. From a starting temperature of 28 degrees C they were exposed to a 2 degrees C rise in temperature every 30 min until all mosquitoes had escaped or been knocked down. As temperature increased, A. arabiensis left the holding tube at higher temperatures than A. gambiae s.s. (A. arabiensis mean activation temperature = 35.7 degrees C, 95% CIs = 35.4-36.1 degrees C; A. gambiae s.s. = 33.0 degrees C, 32.5-33.5 degrees C). To determine the relative ability of both species to survive at extremely high temperatures, batches of insects were exposed to 40 degrees C for different periods. It took considerably longer to kill 50% of A. arabiensis at 40 degrees C than it did A. gambiae s.s. (112 min vs. 67 min). These data show that adult A. arabiensis are better adapted to hotter conditions than A. gambiae s.s., a characteristic that is reflected in their spatial and temporal distribution in Africa.

  7. Non-destructive determination of age and species of Anopheles gambiae s.l. using near-infrared spectroscopy.

    PubMed

    Mayagaya, Valeliana S; Michel, Kristin; Benedict, Mark Q; Killeen, Gerry F; Wirtz, Robert A; Ferguson, Heather M; Dowell, Floyd E

    2009-10-01

    Determining malaria vector species and age is crucial to measure malaria risk. Although different in ecology and susceptibility to control, the African malaria vectors Anopheles gambiae sensu stricto and An. arabiensis are morphologically similar and can be differentiated only by molecular techniques. Furthermore, few reliable methods exist to estimate the age of these vectors, which is a key predictor of malaria transmission intensity. We evaluated the use of near-infrared spectroscopy (NIRS) to determine vector species and age. This non-destructive technique predicted the species of field-collected mosquitoes with approximately 80% accuracy and predicted the species of laboratory-reared insects with almost 100% accuracy. The relative age of young or old females was predicted with approximately 80% accuracy, and young and old insects were predicted with > or = 90% accuracy. For applications where rapid assessment of the age structure and species composition of wild vector populations is needed, NIRS offers a valuable alternative to traditional methods.

  8. Relationship between kdr mutation and resistance to pyrethroid and DDT insecticides in natural populations of Anopheles gambiae.

    PubMed

    Reimer, Lisa; Fondjo, Etienne; Patchoké, Salomon; Diallo, Brehima; Lee, Yoosook; Ng, Arash; Ndjemai, Hamadou M; Atangana, Jean; Traore, Sekou F; Lanzaro, Gregory; Cornel, Anthony J

    2008-03-01

    The spread of insecticide resistance genes in Anopheles gambiae Giles sensu stricto threatens to compromise vector-based malaria control programs. Two mutations at the same locus in the voltage-gated sodium channel gene are known to confer knockdown resistance (kdr) to pyrethroids and DDT. Kdr-e involves a leucine-serine substitution, and it was until recently thought to be restricted to East Africa, whereas kdr-w, which involves a leucine-phenylalanine substitution, is associated with resistance in West Africa. In this study, we analyze the frequency and relationship between the kdr genotypes and resistance to type I and type II pyrethroids and DDT by using WHO test kits in both the Forest-M and S molecular forms of An. gambiae in Cameroon. Both kdr-w and kdr-e polymorphisms were found in sympatric An. gambiae, and in many cases in the same mosquito. Kdr-e and kdr-w were detected in both forms, but they were predominant in the S form. Both kdr-e and kdr-w were closely associated with resistance to DDT and weakly associated with resistance to type II pyrethroids. Kdr-w conferred greater resistance to permethrin than kdr-e. We also describe a modified diagnostic designed to detect both resistant alleles simultaneously.

  9. Identification and validation of a gene causing cross-resistance between insecticide classes in Anopheles gambiae from Ghana

    PubMed Central

    Mitchell, Sara N.; Stevenson, Bradley J.; Müller, Pie; Wilding, Craig S.; Egyir-Yawson, Alexander; Field, Stuart G.; Hemingway, Janet; Paine, Mark J. I.; Ranson, Hilary; Donnelly, Martin James

    2012-01-01

    In the last decade there have been marked reductions in malaria incidence in sub-Saharan Africa. Sustaining these reductions will rely upon insecticides to control the mosquito malaria vectors. We report that in the primary African malaria vector, Anopheles gambiae sensu stricto, a single enzyme, CYP6M2, confers resistance to two classes of insecticide. This is unique evidence in a disease vector of cross-resistance associated with a single metabolic gene that simultaneously reduces the efficacy of two of the four classes of insecticide routinely used for malaria control. The gene-expression profile of a highly DDT-resistant population of A. gambiae s.s. from Ghana was characterized using a unique whole-genome microarray. A number of genes were significantly overexpressed compared with two susceptible West African colonies, including genes from metabolic families previously linked to insecticide resistance. One of the most significantly overexpressed probe groups (false-discovery rate-adjusted P < 0.0001) belonged to the cytochrome P450 gene CYP6M2. This gene is associated with pyrethroid resistance in wild A. gambiae s.s. populations) and can metabolize both type I and type II pyrethroids in recombinant protein assays. Using in vitro assays we show that recombinant CYP6M2 is also capable of metabolizing the organochlorine insecticide DDT in the presence of solubilizing factor sodium cholate. PMID:22460795

  10. Larval nutrition differentially affects adult fitness and Plasmodium development in the malaria vectors Anopheles gambiae and Anopheles stephensi.

    PubMed

    Takken, Willem; Smallegange, Renate C; Vigneau, Antoine J; Johnston, Valerie; Brown, Margaret; Mordue-Luntz, A Jenny; Billingsley, Peter F

    2013-12-10

    Mosquito fitness is determined largely by body size and nutritional reserves. Plasmodium infections in the mosquito and resultant transmission of malaria parasites might be compromised by the vector's nutritional status. We studied the effects of nutritional stress and malaria parasite infections on transmission fitness of Anopheles mosquitoes. Larvae of Anopheles gambiae sensu stricto and An. stephensi were reared at constant density but with nutritionally low and high diets. Fitness of adult mosquitoes resulting from each dietary class was assessed by measuring body size and lipid, protein and glycogen content. The size of the first blood meal was estimated by protein analysis. Mosquitoes of each dietary class were fed upon a Plasmodium yoelii nigeriensis-infected mouse, and parasite infections were determined 5 d after the infectious blood meal by dissection of the midguts and by counting oocysts. The impact of Plasmodium infections on gonotrophic development was established by dissection. Mosquitoes raised under low and high diets emerged as adults of different size classes comparable between An. gambiae and An. stephensi. In both species low-diet females contained less protein, lipid and glycogen upon emergence than high-diet mosquitoes. The quantity of larval diet impacted strongly upon adult blood feeding and reproductive success. The prevalence and intensity of P. yoelii nigeriensis infections were reduced in low-diet mosquitoes of both species, but P. yoelii nigeriensis impacted negatively only on low-diet, small-sized An. gambiae considering survival and egg maturation. There was no measurable fitness effect of P. yoelii nigeriensis on An. stephensi. Under the experimental conditions, small-sized An. gambiae expressed high mortality, possibly caused by Plasmodium infections, the species showing distinct physiological concessions when nutrionally challenged in contrast to well-fed, larger siblings. Conversely, An. stephensi was a robust, successful vector

  11. Larvicidal efficacy of Cryptomeria japonica leaf essential oils against Anopheles gambiae.

    PubMed

    Mdoe, France P; Cheng, Sen-Sung; Lyaruu, Lucile; Nkwengulila, Gamba; Chang, Shang-Tzen; Kweka, Eliningaya J

    2014-09-04

    Alternative insecticidal compounds with mortality effect against mosquito life cycle stages are currently needed. The compounds should be biodegradable and nontoxic to non-targeted insects. Plant based larvicides provide effective control of vector populations. This study explored Cryptomeria japonica leaf essential oil larvicidal potency against Anopheles gambiae sensu stricto. Essential oils (12.5 to 200 μg/mL) extracted from C. japonica leaves were evaluated against An. gambiae s.s. larvae in both the laboratory and semi field in 6 replicates for each dose. Larval mortality readings were taken at 12, 24, 48, and 72 h post treatment. C. japonica leaf essential oil yield was 17.06 ± 0.56 mL/kg and 1.60 ± 0.33% (w/w). GC-FID and GC-MS analyses revealed 22 constituents. Essential oil was more effective against An. gambiae s.s. larvae in the laboratory than in semi field trials. Mortality increased with increasing dosages (12.5 to 200 μg/mL) in the laboratory (31.75 to 100%) and semi field trials (17.75 to 99.5%), respectively. The LC50 value ranged from 5.55 to 63.92 μg/mL in the laboratory, and 8.22 to 134.84 μg/mL in semi field conditions, LC90 value ranged from 41.34 to 205.93 μg/mL in the laboratory and 50.92 to 213.11 μg/mL in semi field conditions. This study has demonstrated the potential of C. japonica leaf essential oil to cause mortality effects to An. gambiae s. s. larval populations, however, further studies need to be conducted under field conditions and also with individual active compounds of C. japonica essential oil.

  12. Larval density dependence in Anopheles gambiae s.s., the major African vector of malaria

    PubMed Central

    Muriu, Simon M.; Coulson, Tim; Mbogo, Charles M.; Godfray, H. Charles J.

    2017-01-01

    Summary Anopheles gambiae sensu stricto is the most important vector of malaria in Africa although relatively little is known about the density-dependent processes determining its population size.Mosquito larval density was manipulated under semi-natural conditions using artificial larval breeding sites placed in the field in coastal Kenya; two experiments were conducted: one manipulating the density of a single cohort of larvae across a range of densities and the other employing fewer densities but with the treatments crossed with four treatments manipulating predator access.In the first experiment, larval survival, development rate and the size of the adult mosquito all decreased with larval density (controlling for block effects between 23% and 31% of the variance in the data could be explained by density).In the second experiment, the effects of predator manipulation were not significant, but again we observed strong density dependence in larval survival (explaining 30% of the variance).The results are compared with laboratory studies of A. gambiae larval competition and the few other studies conducted in the field, and the consequences for malaria control are discussed PMID:23163565

  13. Larval density dependence in Anopheles gambiae s.s., the major African vector of malaria.

    PubMed

    Muriu, Simon M; Coulson, Tim; Mbogo, Charles M; Godfray, H Charles J

    2013-01-01

    Anopheles gambiae sensu stricto is the most important vector of malaria in Africa although relatively little is known about the density-dependent processes determining its population size. Mosquito larval density was manipulated under semi-natural conditions using artificial larval breeding sites placed in the field in coastal Kenya; two experiments were conducted: one manipulating the density of a single cohort of larvae across a range of densities and the other employing fewer densities but with the treatments crossed with four treatments manipulating predator access. In the first experiment, larval survival, development rate and the size of the adult mosquito all decreased with larval density (controlling for block effects between 23% and 31% of the variance in the data could be explained by density). In the second experiment, the effects of predator manipulation were not significant, but again we observed strong density dependence in larval survival (explaining 30% of the variance). The results are compared with laboratory studies of A. gambiae larval competition and the few other studies conducted in the field, and the consequences for malaria control are discussed. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.

  14. Biofilm formation by Borrelia burgdorferi sensu lato.

    PubMed

    Timmaraju, Venkata Arun; Theophilus, Priyanka A S; Balasubramanian, Kunthavai; Shakih, Shafiq; Luecke, David F; Sapi, Eva

    2015-08-01

    Bacterial biofilms are microbial communities held together by an extracellular polymeric substance matrix predominantly composed of polysaccharides, proteins and nucleic acids. We had previously shown that Borrelia burgdorferi sensu stricto, the causative organism of Lyme disease in the United States is capable of forming biofilms in vitro. Here, we investigated biofilm formation by B. afzelii and B. garinii, which cause Lyme disease in Europe. Using various histochemistry and microscopy techniques, we show that B. afzelii and B. garinii form biofilms, which resemble biofilms formed by B. burgdorferi sensu stricto. High-resolution atomic force microscopy revealed similarities in the ultrastructural organization of the biofilms form by three Borrelia species. Histochemical experiments revealed a heterogeneous organization of exopolysaccharides among the three Borrelia species. These results suggest that biofilm formation might be a common trait of Borrelia genera physiology.

  15. Identification of the main malaria vectors in the Anopheles gambiae species complex using a TaqMan real-time PCR assay.

    PubMed

    Bass, Chris; Williamson, Martin S; Wilding, Craig S; Donnelly, Martin J; Field, Linda M

    2007-11-22

    The Anopheles gambiae sensu lato species complex comprises seven sibling species of mosquitoes that are morphologically indistinguishable. Rapid identification of the two main species which vector malaria, Anopheles arabiensis and An. gambiae sensu stricto, from the non-vector species Anopheles quadriannulatus is often required as part of vector control programmes. Currently the most widely used method for species identification is a multiplex PCR protocol that targets species specific differences in ribosomal DNA sequences. While this assay has proved to be reasonably robust in many studies, additional steps are required post-PCR making it time consuming. Recently, a high-throughput assay based on TaqMan single nucleotide polymorphism genotyping that detects and discriminates An. gambiae s.s and An. arabiensis has been reported. A new TaqMan assay was developed that distinguishes between the main malaria vectors (An. arabiensis and An. gambiae s.s.) and the non-vector An. quadriannulatus after it was found that the existing TaqMan assay incorrectly identified An. quadriannulatus, An. merus and An. melas as An. gambiae s.s. The performance of this new TaqMan assay was compared against the existing TaqMan assay and the standard PCR method in a blind species identification trial of over 450 samples using field collected specimens from a total of 13 countries in Sub-Saharan Africa. The standard PCR method was found to be specific with a low number of incorrect scores (<1%), however when compared to the TaqMan assays it showed a significantly higher number of failed reactions (15%). Both the new vector-specific TaqMan assay and the exisiting TaqMan showed a very low number of incorrectly identified samples (0 and 0.54%) and failed reactions (1.25% and 2.96%). In tests of analytical sensitivity the new TaqMan assay showed a very low detection threshold and can consequently be used on a single leg from a fresh or silica-dried mosquito without the need to first extract

  16. Improvement of a synthetic lure for Anopheles gambiae using compounds produced by human skin microbiota

    PubMed Central

    2011-01-01

    Background Anopheles gambiae sensu stricto is considered to be highly anthropophilic and volatiles of human origin provide essential cues during its host-seeking behaviour. A synthetic blend of three human-derived volatiles, ammonia, lactic acid and tetradecanoic acid, attracts A. gambiae. In addition, volatiles produced by human skin bacteria are attractive to this mosquito species. The purpose of the current study was to test the effect of ten compounds present in the headspace of human bacteria on the host-seeking process of A. gambiae. The effect of each of the ten compounds on the attractiveness of a basic blend of ammonia, lactic and tetradecanoic acid to A. gambiae was examined. Methods The host-seeking response of A. gambiae was evaluated in a laboratory set-up using a dual-port olfactometer and in a semi-field facility in Kenya using MM-X traps. Odorants were released from LDPE sachets and placed inside the olfactometer as well as in the MM-X traps. Carbon dioxide was added in the semi-field experiments, provided from pressurized cylinders or fermenting yeast. Results The olfactometer and semi-field set-up allowed for high-throughput testing of the compounds in blends and in multiple concentrations. Compounds with an attractive or inhibitory effect were identified in both bioassays. 3-Methyl-1-butanol was the best attractant in both set-ups and increased the attractiveness of the basic blend up to three times. 2-Phenylethanol reduced the attractiveness of the basic blend in both bioassays by more than 50%. Conclusions Identification of volatiles released by human skin bacteria led to the discovery of compounds that have an impact on the host-seeking behaviour of A. gambiae. 3-Methyl-1-butanol may be used to increase mosquito trap catches, whereas 2-phenylethanol has potential as a spatial repellent. These two compounds could be applied in push-pull strategies to reduce mosquito numbers in malaria endemic areas. PMID:21303496

  17. Behavioral response of the malaria mosquito, Anopheles gambiae, to human sweat inoculated with axilla bacteria and to volatiles composing human axillary odor.

    PubMed

    Frei, Jérôme; Kröber, Thomas; Troccaz, Myriam; Starkenmann, Christian; Guerin, Patrick M

    2017-02-01

    The responses of Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) to odors from male and female axillary sweat incubated with human axilla bacteria were recorded in a dual-choice olfactometer. Staphylococcus epidermidis was selected for its low odor-producing pattern, Corynebacterium jeikeium for its strong Nα-acylglutamine aminoacylase activity liberating carboxylic acids including (R)/(S)-3-hydroxy-3-methylhexanoic acid (HMHA) and Staphylococcus haemolyticus for its capacity to liberate sulfur-containing compounds including (R/S)-3-methyl-3-sulfanylhexan-1-ol (MSH). Anopheles gambiae behavioral responses were evaluated under (i) its responsiveness to take off and undertake sustained upwind flight and (ii) its discriminating capacity between the two olfactometer arms bearing a test odor in either one or both arms. Experiments were conducted in the presence of carbon dioxide pulses as a behavioral sensitizer. Anopheles gambiae clearly discriminated for the olfactometer arm conveying odor generated by incubating any of the three bacteria species with either male or female sweat. Whereas An. gambiae did not discriminate between male and female sterile sweat samples in the olfactometer, the mosquito consistently showed a preference for male sweat over female sweat incubated with the same bacterium, independent of the species used as inoculum. Sweat incubated with C. jeikeium rendered mosquitoes particularly responsive and this substrate elicited the strongest preference for male over female sweat. Tested on their own, neither HMHA nor MSH elicited a clear discriminating response but did affect mosquito responsiveness. These findings serve as a basis for further research on the odor-mediated anthropophilic host-seeking behavior of An. gambiae. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Mapping distributions of chromosomal forms of Anopheles gambiae in West Africa using climate data.

    PubMed

    Bayoh, M N; Thomas, C J; Lindsay, S W

    2001-09-01

    The mosquito Anopheles gambiae Giles sensu stricto (Diptera: Culicidae), the principal vector of malaria in West Africa, comprises several chromosomal forms (e.g. Bissau, Forest, Mopti, Savanna) associated with climatic zones. Here we show how climate data can be used to map the geographical distribution of these chromosomal forms. The climate at 144 sites surveyed for mosquitoes in West Africa between 1971 and 92 was determined using computerized climate surfaces. Forest and Bissau forms occurred at relatively wet sites: median annual precipitation 1325 mm and 1438 mm, respectively, interquartile ranges (IQR) 1144-1858 mm and 1052-1825 mm), whilst the Mopti form was found at dry sites (annual 938 mm, IQR 713-1047 mm) and the Savanna form at sites intermediate between the wet and dry forms (annual 1067 mm, IQR 916-1279). Logistic regression analyses of the climate variables were carried out on a stratified random sample of half the sites. The resulting models correctly classified over 80% of the sites for presence or absence of each chromosomal form. When these models were tested against excluded sites they were also correct at over 80% of sites. The combined data produced models that were correct at over 86% of sites. Mean annual precipitation, evapotranspiration, minimum temperature and maximum temperature were the most important climate variables correlated with the distribution of these forms of An. gambiae. We used the logistic models to map the distribution of each chromosomal form within the reported range for An. gambiae s.s. in West Africa employing a geographical information system. Our maps indicate that each chromosomal form favours particular climate envelopes in well-defined ecoclimatic zones, although these forms are sympatric at the edges of their ranges. This study demonstrates that climate can be used to map the distribution of chromosomal forms of insects across large areas.

  19. Biological cost of tolerance to heavy metals in the mosquito Anopheles gambiae.

    PubMed

    Mireji, P O; Keating, J; Hassanali, A; Mbogo, C M; Muturi, M N; Githure, J I; Beier, J C

    2010-06-01

    The global rate of heavy metal pollution is rapidly increasing in various habitats. Anopheles malaria vector species (Diptera: Culicidae) appear to tolerate many aquatic habitats with metal pollutants, despite their normal proclivity for 'clean' water (i.e. low levels of organic matter). Investigations were conducted to establish whether there are biological costs for tolerance to heavy metals in Anopheles gambiae Giles sensu stricto and to assess the potential impact of heavy metal pollution on mosquito ecology. Anopheles gambiae s.s. were selected for cadmium, copper or lead tolerance through chronic exposure of immature stages to solutions of the metals for three successive generations. Biological costs were assessed in the fourth generation by horizontal life table analysis. Tolerance in larvae to cadmium (as cadmium chloride, CdCl(2)), copper [as copper II nitrate hydrate, Cu(NO(3))(2) 2.5 H(2)O] and lead [as lead II nitrate, Pb(NO(3))(2)], monitored by changes in LC(50) concentrations of the metals, changed from 6.07 microg/L, 12.42 microg/L and 493.32 microg/L to 4.45 microg/L, 25.02 microg/L and 516.69 microg/L, respectively, after three generations of exposure. The metal-selected strains had a significantly lower magnitude of egg viability, larval and pupal survivorship, adult emergence, fecundity and net reproductive rate than the control strain. The population doubling times were significantly longer and the instantaneous birth rates lower in most metal-selected strains relative to the control strain. Our results suggest that although An. gambiae s.s. displays the potential to develop tolerance to heavy metals, particularly copper, this may occur at a significant biological cost, which can adversely affect its ecological fitness.

  20. Candida parapsilosis (sensu lato) isolated from hospitals located in the Southeast of Brazil: Species distribution, antifungal susceptibility and virulence attributes.

    PubMed

    Ziccardi, Mariangela; Souza, Lucieri O P; Gandra, Rafael M; Galdino, Anna Clara M; Baptista, Andréa R S; Nunes, Ana Paula F; Ribeiro, Mariceli A; Branquinha, Marta H; Santos, André L S

    2015-12-01

    Candida parapsilosis (sensu lato), which represents a fungal complex composed of three genetically related species - Candida parapsilosis sensu stricto, Candida orthopsilosis and Candida metapsilosis, has emerged as an important yeast causing fungemia worldwide. The goal of the present work was to assess the prevalence, antifungal susceptibility and production of virulence traits in 53 clinical isolates previously identified as C. parapsilosis (sensu lato) obtained from hospitals located in the Southeast of Brazil. Species forming this fungal complex are physiologically/morphologically indistinguishable; however, polymerase chain reaction followed by restriction fragment length polymorphism of FKS1 gene has solved the identification inaccuracy, revealing that 43 (81.1%) isolates were identified as C. parapsilosis sensu stricto and 10 (18.9%) as C. orthopsilosis. No C. metapsilosis was found. The geographic distribution of these Candida species was uniform among the studied Brazilian States (São Paulo, Rio de Janeiro and Espírito Santo). All C. orthopsilosis and almost all C. parapsilosis sensu stricto (95.3%) isolates were susceptible to amphotericin B, fluconazole, itraconazole, voriconazole and caspofungin. Nevertheless, one C. parapsilosis sensu stricto isolate was resistant to fluconazole and another one was resistant to caspofungin. C. parapsilosis sensu stricto isolates exhibited higher MIC mean values to amphotericin B, fluconazole and caspofungin than those of C. orthopsilosis, while C. orthopsilosis isolates displayed higher MIC mean to itraconazole compared to C. parapsilosis sensu stricto. Identical MIC mean values to voriconazole were measured for these Candida species. All the isolates of both species were able to form biofilm on polystyrene surface. Impressively, biofilm-growing cells of C. parapsilosis sensu stricto and C. orthopsilosis exhibited a considerable resistance to all antifungal agents tested. Pseudohyphae were observed in 67.4% and 80

  1. Autodissemination of the entomopathogenic fungus Metarhizium anisopliae amongst adults of the malaria vector Anopheles gambiae s.s.

    PubMed Central

    Scholte, Ernst-Jan; Knols, Bart GJ; Takken, Willem

    2004-01-01

    Background The entomopathogenic fungus Metarhizium anisopliae is being considered as a biocontrol agent for adult African malaria vectors. In the laboratory, work was carried out to assess whether horizontal transmission of the pathogen can take place during copulation, as this would enhance the impact of the fungus on target populations when compared with insecticides. Methods Virgin female Anopheles gambiae sensu stricto were exposed to conidia whilst resting on fungus-impregnated paper. These females were then placed together for one hour with uncontaminated males in proportions of either 1:1 or 1:10 shortly before the onset of mating activity. Results Males that had acquired fungal infection after mating indicate that passive transfer of the pathogen from infected females does occur, with mean male infection rates between 10.7 ± 3.2% and 33.3 ± 3.8%. The infections caused by horizontal transmission did not result in overall differences in survival between males from test and control groups, but in one of the three experiments the infected males had significantly shorter life spans than uninfected males (P < 0.05). Conclusion This study shows that autodissemination of fungal inoculum between An. gambiae s.s. mosquitoes during mating activity is possible under laboratory conditions. Field studies are required next, to assess the extent to which this phenomenon may augment the primary contamination pathway (i.e. direct contact with fungus-impregnated targets) of vector populations in the field. PMID:15566626

  2. EVALUATION OF POSTGRADUATES STRICTO SENSU: MONITORING POLICY FOR INTERNATIONAL GRADUATES.

    PubMed

    Lima, Wilma Terezinha Anselmo

    2015-01-01

    Search for references in relationship to international alumni on the website of the postgraduate programs of all postgraduate courses at Ribeirão Preto Medical School - FMRP. Verify with more attention to the ones with 5, 6 and 7 notes, and also the same search on the website of courses with notes 5, 6 and 7 of CAPES - Medicine III. Of the 22 programs of FMRP only three had any information on the site about the destiny of the postgraduates; they were: Surgical Clinics, Genetics, and Basic and Applied Immunology. Programs in the area of ​​Medicine III, notes 5, 6 and 7, only Ophthalmology and Visual Programs and Translational Sciences Surgery, both of UNIFESP, presented such information. It is urgent: to create project and funding evaluation mechanisms that are approved by different sources; to stimulate more efficient controls in relation to teachers and their students who participate in these projects; and to stimulate the interaction of teachers and students with the institution and the program. Verificar a existência de referências aos egressos internacionais nos sites dos programas de pós-graduação de todos os cursos de pós-graduação da Faculdade de Medicina de Ribeirão Preto - FMRP. Verificar com mais atenção aos cursos notas 5, 6 e 7, e também a mesma busca nos sites dos cursos com notas 5, 6 e 7 da Medicina III da CAPES. Dos 22 programas da FMRP apenas três tinham no site alguma informação sobre o destino dos egressos, foram eles: Clínica Cirúrgica, Genética e Imunologia Básica e Aplicada. Dos programas da área de Medicina III, notas 5, 6 e 7 apenas os programas de Oftalmologia e Ciências Visuais e Cirurgia Translacional, ambos da UNIFESP, apresentavam informações sobre o destino dos seus egressos. É urgente criar mecanismos de avaliação para os projetos de incentivo e fomento à pesquisa dos diferentes órgãos; estimular controles mais eficientes e atualizados em relação aos docentes e seus respectivos discentes que participam desses projetos; e estimular a interação dos docentes e discentes com a instituição e o programa.

  3. Distribution of knock-down resistance mutations in Anopheles gambiae molecular forms in west and west-central Africa

    PubMed Central

    Santolamazza, Federica; Calzetta, Maria; Etang, Josiane; Barrese, Elena; Dia, Ibrahima; Caccone, Adalgisa; Donnelly, Martin J; Petrarca, Vincenzo; Simard, Frederic; Pinto, Joao; della Torre, Alessandra

    2008-01-01

    Background Knock-down resistance (kdr) to DDT and pyrethroids in the major Afrotropical vector species, Anopheles gambiae sensu stricto, is associated with two alternative point mutations at amino acid position 1014 of the voltage-gated sodium channel gene, resulting in either a leucine-phenylalanine (L1014F), or a leucine-serine (L1014S) substitution. In An. gambiae S-form populations, the former mutation appears to be widespread in west Africa and has been recently reported from Uganda, while the latter, originally recorded in Kenya, has been recently found in Gabon, Cameroon and Equatorial Guinea. In M-form populations surveyed to date, only the L1014F mutation has been found, although less widespread and at lower frequencies than in sympatric S-form populations. Methods Anopheles gambiae M- and S-form specimens from 19 sites from 11 west and west-central African countries were identified to molecular form and genotyped at the kdr locus either by Hot Oligonucleotide Ligation Assay (HOLA) or allele-specific PCR (AS-PCR). Results The kdr genotype was determined for about 1,000 An. gambiae specimens. The L1014F allele was found at frequencies ranging from 6% to 100% in all S-form samples (N = 628), with the exception of two samples from Angola, where it was absent, and coexisted with the L1014S allele in samples from Cameroon, Gabon and north-western Angola. The L1014F allele was present in M-form samples (N = 354) from Benin, Nigeria, and Cameroon, where both M- and S-forms were sympatric. Conclusion The results represent the most comprehensive effort to analyse the overall distribution of the L1014F and L1014S mutations in An. gambiae molecular forms, and will serve as baseline data for resistance monitoring. The overall picture shows that the emergence and spread of kdr alleles in An. gambiae is a dynamic process and that there is marked intra- and inter-form heterogeneity in resistance allele frequencies. Further studies are needed to determine: i) the

  4. Insecticide resistance mechanisms associated with different environments in the malaria vector Anopheles gambiae: a case study in Tanzania

    PubMed Central

    2014-01-01

    Background Resistance of mosquitoes to insecticides is a growing concern in Africa. Since only a few insecticides are used for public health and limited development of new molecules is expected in the next decade, maintaining the efficacy of control programmes mostly relies on resistance management strategies. Developing such strategies requires a deep understanding of factors influencing resistance together with characterizing the mechanisms involved. Among factors likely to influence insecticide resistance in mosquitoes, agriculture and urbanization have been implicated but rarely studied in detail. The present study aimed at comparing insecticide resistance levels and associated mechanisms across multiple Anopheles gambiae sensu lato populations from different environments. Methods Nine populations were sampled in three areas of Tanzania showing contrasting agriculture activity, urbanization and usage of insecticides for vector control. Insecticide resistance levels were measured in larvae and adults through bioassays with deltamethrin, DDT and bendiocarb. The distribution of An. gambiae sub-species and pyrethroid target-site mutations (kdr) were investigated using molecular assays. A microarray approach was used for identifying transcription level variations associated to different environments and insecticide resistance. Results Elevated resistance levels to deltamethrin and DDT were identified in agriculture and urban areas as compared to the susceptible strain Kisumu. A significant correlation was found between adult deltamethrin resistance and agriculture activity. The subspecies Anopheles arabiensis was predominant with only few An. gambiae sensu stricto identified in the urban area of Dar es Salaam. The L1014S kdr mutation was detected at elevated frequency in An gambiae s.s. in the urban area but remains sporadic in An. arabiensis specimens. Microarrays identified 416 transcripts differentially expressed in any area versus the susceptible reference

  5. Infection of malaria (Anopheles gambiae s.s.) and filariasis (Culex quinquefasciatus) vectors with the entomopathogenic fungus Metarhizium anisopliae

    PubMed Central

    Scholte, Ernst-Jan; Njiru, Basilio N; Smallegange, Renate C; Takken, Willem; Knols, Bart GJ

    2003-01-01

    Background Current intra-domiciliary vector control depends on the application of residual insecticides and/or repellents. Although biological control agents have been developed against aquatic mosquito stages, none are available for adults. Following successful use of an entomopathogenic fungus against tsetse flies (Diptera: Glossinidae) we investigated the potency of this fungus as a biological control agent for adult malaria and filariasis vector mosquitoes. Methods In the laboratory, both sexes of Anopheles gambiae sensu stricto and Culex quinquefasciatus were passively contaminated with dry conidia of Metarhizium anisopliae. Pathogenicity of this fungus for An. gambiae was further tested for varying exposure times and different doses of oil-formulated conidia. Results Comparison of Gompertz survival curves and LT50 values for treated and untreated specimens showed that, for both species, infected mosquitoes died significantly earlier (p < 0.0001) than uninfected control groups. No differences in LT50 values were found for different exposure times (24, 48 hrs or continuous exposure) of An. gambiae to dry conidia. Exposure to oil-formulated conidia (doses ranging from 1.6 × 107 to 1.6 × 1010 conidia/m2) gave LT50 values of 9.69 ± 1.24 (lowest dose) to 5.89 ± 0.35 days (highest dose), with infection percentages ranging from 4.4–83.7%. Conclusion Our study marks the first to use an entomopathogenic fungus against adult Afrotropical disease vectors. Given its high pathogenicity for both adult Anopheles and Culex mosquitoes we recommend development of novel targeted indoor application methods for the control of endophagic host-seeking females. PMID:14565851

  6. Infection of malaria (Anopheles gambiae s.s.) and filariasis (Culex quinquefasciatus) vectors with the entomopathogenic fungus Metarhizium anisopliae.

    PubMed

    Scholte, Ernst-Jan; Njiru, Basilio N; Smallegange, Renate C; Takken, Willem; Knols, Bart G J

    2003-09-15

    Current intra-domiciliary vector control depends on the application of residual insecticides and/or repellents. Although biological control agents have been developed against aquatic mosquito stages, none are available for adults. Following successful use of an entomopathogenic fungus against tsetse flies (Diptera: Glossinidae) we investigated the potency of this fungus as a biological control agent for adult malaria and filariasis vector mosquitoes. In the laboratory, both sexes of Anopheles gambiae sensu stricto and Culex quinquefasciatus were passively contaminated with dry conidia of Metarhizium anisopliae. Pathogenicity of this fungus for An. gambiae was further tested for varying exposure times and different doses of oil-formulated conidia. Comparison of Gompertz survival curves and LT50 values for treated and untreated specimens showed that, for both species, infected mosquitoes died significantly earlier (p < 0.0001) than uninfected control groups. No differences in LT50 values were found for different exposure times (24, 48 hrs or continuous exposure) of An. gambiae to dry conidia. Exposure to oil-formulated conidia (doses ranging from 1.6 x 10(7) to 1.6 x 10(10) conidia/m2) gave LT50 values of 9.69 +/- 1.24 (lowest dose) to 5.89 +/- 0.35 days (highest dose), with infection percentages ranging from 4.4-83.7%. Our study marks the first to use an entomopathogenic fungus against adult Afrotropical disease vectors. Given its high pathogenicity for both adult Anopheles and Culex mosquitoes we recommend development of novel targeted indoor application methods for the control of endophagic host-seeking females.

  7. The transmission potential of malaria-infected mosquitoes (An.gambiae-Keele, An.arabiensis-Ifakara) is altered by the vertebrate blood type they consume during parasite development.

    PubMed

    Emami, S Noushin; Ranford-Cartwright, Lisa C; Ferguson, Heather M

    2017-01-17

    The efficiency of malaria parasite development within mosquito vectors (sporogony) is a critical determinant of transmission. Sporogony is thought to be controlled by environmental conditions and mosquito/parasite genetic factors, with minimal contribution from mosquito behaviour during the period of parasite development. We tested this assumption by investigating whether successful sporogony of Plasmodium falciparum parasites through to human-infectious transmission stages is influenced by the host species upon which infected mosquitoes feed. Studies were conducted on two major African vector species that generally are found to differ in their innate host preferences: Anopheles arabiensis and An. gambiae sensu stricto. We show that the proportion of vectors developing transmissible infections (sporozoites) was influenced by the source of host blood consumed during sporogony. The direction of this effect was associated with the innate host preference of vectors: higher sporozoite prevalences were generated in the usually human-specialist An. gambiae s.s. feeding on human compared to cow blood, whereas the more zoophilic An. arabiensis had significantly higher prevalences after feeding on cow blood. The potential epidemiological implications of these results are discussed.

  8. The transmission potential of malaria-infected mosquitoes (An.gambiae-Keele, An.arabiensis-Ifakara) is altered by the vertebrate blood type they consume during parasite development

    PubMed Central

    Emami, S. Noushin; Ranford-Cartwright, Lisa C.; Ferguson, Heather M.

    2017-01-01

    The efficiency of malaria parasite development within mosquito vectors (sporogony) is a critical determinant of transmission. Sporogony is thought to be controlled by environmental conditions and mosquito/parasite genetic factors, with minimal contribution from mosquito behaviour during the period of parasite development. We tested this assumption by investigating whether successful sporogony of Plasmodium falciparum parasites through to human-infectious transmission stages is influenced by the host species upon which infected mosquitoes feed. Studies were conducted on two major African vector species that generally are found to differ in their innate host preferences: Anopheles arabiensis and An. gambiae sensu stricto. We show that the proportion of vectors developing transmissible infections (sporozoites) was influenced by the source of host blood consumed during sporogony. The direction of this effect was associated with the innate host preference of vectors: higher sporozoite prevalences were generated in the usually human-specialist An. gambiae s.s. feeding on human compared to cow blood, whereas the more zoophilic An. arabiensis had significantly higher prevalences after feeding on cow blood. The potential epidemiological implications of these results are discussed. PMID:28094293

  9. Progression to active tuberculosis, but not transmission, varies by M. tuberculosis lineage in The Gambia

    PubMed Central

    de Jong, Bouke C.; Hill, Philip C.; Aiken, Alex; Awine, Timothy; Antonio, Martin; Adetifa, Ifedayo M.; Jackson-Sillah, Dolly J.; Fox, Annette; DeRiemer, Kathryn; Gagneux, Sebastien; Borgdorff, Martien W.; McAdam, Keith P.W.J.; Corrah, Tumani; Small, Peter M.; Adegbola, Richard A.

    2008-01-01

    Considerable variability exists in the outcome of M. tuberculosis infection. We hypothesized that M. africanum was less likely than M. tuberculosis to transmit and progress to tuberculosis disease. In a cohort study of tuberculosis patients and their household contacts in the Gambia, we categorized 1,808 HIV negative tuberculosis contacts according to exposure to M. tuberculosis or to M. africanum. A positive skin test indicated transmission and development of tuberculosis during 2 years of follow-up indicated progression to disease. Transmission was similar, but progression to disease was significantly lower in contacts exposed to M. africanum than to M. tuberculosis (1.0% vs 2.9%; Hazard Ratio (HR) 3.1, 95% CI 1.1–8.7). Within M. tuberculosis sensu stricto, contacts exposed to a Beijing family strain were most likely to progress to disease (5.6%; HR 6.7 (2.0–22) relative to M. africanum). M. africanum and M. tuberculosis transmit equally well to household contacts, but contacts exposed to M. africanum are less likely to progress to tuberculosis disease than those exposed to M. tuberculosis. The variable rate of progression by lineage suggests that TB variability matters in clinical settings and should be taken into account in studies evaluating tuberculosis vaccines and treatment regimens for latent tuberculosis infection. PMID:18702608

  10. Whole genome sequence of an unusual Borrelia burgdorferi sensu lato isolate

    SciTech Connect

    Casjens, S.R.; Dunn, J.; Fraser-Liggett, C. M.; Mongodin, E. F.; Qiu, W. G.; Luft, B. J.; Schutzer, S. E.

    2011-03-01

    Human Lyme disease is caused by a number of related Borrelia burgdorferi sensu lato species. We report here the complete genome sequence of Borrelia sp. isolate SV1 from Finland. This isolate is to date the closest known relative of B. burgdorferi sensu stricto, but it is sufficiently genetically distinct from that species that it and its close relatives warrant its candidacy for new-species status. We suggest that this isolate should be named 'Borrelia finlandensis.'

  11. Exploring the origin and degree of genetic isolation of Anopheles gambiae from the islands of São Tomé and Príncipe, potential sites for testing transgenic-based vector control

    PubMed Central

    Marshall, Jonathon C; Pinto, João; Charlwood, Jacques Derek; Gentile, Gabriele; Santolamazza, Federica; Simard, Frèdèric; Della Torre, Alessandra; Donnelly, Martin J; Caccone, Adalgisa

    2008-01-01

    The evolutionary processes at play between island and mainland populations of the malaria mosquito vector Anopheles gambiae sensu stricto are of great interest as islands may be suitable sites for preliminary application of transgenic-based vector control strategies. São Tomé and Príncipe, located off the West African coast, have received such attention in recent years. This study investigates the degree of isolation of An. gambiae s.s. populations between these islands and the mainland based on mitochondrial and ribosomal DNA molecular data. We identify possible continental localities from which these island populations derived. For these purposes, we used FST values, haplotype networks, and nested clade analysis to estimate migration rates and patterns. Haplotypes from both markers are geographically widespread across the African continent. Results indicate that the populations from São Tomé and Príncipe are relatively isolated from continental African populations, suggesting they are promising sites for test releases of transgenic individuals. These island populations are possibly derived from two separate continental migrations. This result is discussed in the context of the history of the African slave trade with respect to São Tomé and Príncipe. PMID:25567803

  12. Taxonomy and phylogeny of Pluteus glaucotinctus sensu lato (Agaricales, Basidiomycota), a multicontinental species complex

    Treesearch

    Nelson Menolli; Alfredo Justo; Pedro Arrillaga; C.K. Pradeep; Andrew M. Minnis; Marina. Capelari

    2014-01-01

    In order to better understand species delimitation in the Pluteus glaucotinctus species complex, we present a detailed study based on morphological and DNA sequence (nrITS + tef1) data. Pluteus glaucotinctus sensu stricto is known only from the type collection (Democratic Republic of the Congo), which is re-...

  13. Insecticide Resistance Allele Frequencies in Anopheles gambiae before and after Anti-Vector Interventions in Continental Equatorial Guinea

    PubMed Central

    Reddy, Michael R.; Godoy, Adrian; Dion, Kirstin; Matias, Abrahan; Callender, Kevin; Kiszewski, Anthony E.; Kleinschmidt, Immo; Ridl, Frances C.; Powell, Jeffrey R.; Caccone, Adalgisa; Slotman, Michel A.

    2013-01-01

    Anti-malaria interventions that rely on insecticides can be compromised by insecticide-resistance alleles among malaria vectors. We examined frequency changes of resistance alleles at two loci, knockdown resistance (kdr) and acetylcholinesterase-1 (ace-1), which confer resistance to pyrethroids and DDT, and carbamates, respectively. A total of 7,059 Anopheles gambiae sensu stricto mosquitoes were analyzed from multiple sites across continental Equatorial Guinea. A subset of sites included samples collected pre-intervention (2007) and post-intervention (2009–2011). Both L1014S and L1014F resistance alleles were observed in almost all pre-intervention collections. In particular, L1014F was already at substantial frequencies in M form populations (17.6–74.6%), and at high frequencies (> 50%) in all but two S form populations. Comparison before and throughout anti-vector interventions showed drastic increases in L1014F, presumably caused by intensified selection pressure imposed by pyrethroids used in vector control efforts. In light of these findings, inclusion of other insecticide classes in any anti-vector intervention can be considered prudent. PMID:23438768

  14. Landscape Movements of Anopheles gambiae Malaria Vector Mosquitoes in Rural Gambia

    PubMed Central

    Thomas, Christopher J.; Cross, Dónall E.; Bøgh, Claus

    2013-01-01

    Background For malaria control in Africa it is crucial to characterise the dispersal of its most efficient vector, Anopheles gambiae, in order to target interventions and assess their impact spatially. Our study is, we believe, the first to present a statistical model of dispersal probability against distance from breeding habitat to human settlements for this important disease vector. Methods/Principal Findings We undertook post-hoc analyses of mosquito catches made in The Gambia to derive statistical dispersal functions for An. gambiae sensu lato collected in 48 villages at varying distances to alluvial larval habitat along the River Gambia. The proportion dispersing declined exponentially with distance, and we estimated that 90% of movements were within 1.7 km. Although a ‘heavy-tailed’ distribution is considered biologically more plausible due to active dispersal by mosquitoes seeking blood meals, there was no statistical basis for choosing it over a negative exponential distribution. Using a simple random walk model with daily survival and movements previously recorded in Burkina Faso, we were able to reproduce the dispersal probabilities observed in The Gambia. Conclusions/Significance Our results provide an important quantification of the probability of An. gambiae s.l. dispersal in a rural African setting typical of many parts of the continent. However, dispersal will be landscape specific and in order to generalise to other spatial configurations of habitat and hosts it will be necessary to produce tractable models of mosquito movements for operational use. We show that simple random walk models have potential. Consequently, there is a pressing need for new empirical studies of An. gambiae survival and movements in different settings to drive this development. PMID:23874719

  15. The Gambia.

    PubMed

    1992-12-01

    The Gambia is a country of 11,300 sq. km. with 855,000 inhabitants. Independence was gained on February 18, 1965. The terrain consists of plains and low hills, with a climate which is tropical, yet cooler and dry from November to May. English, Mandinka, Wolof, Fula, and other indigenous languages are spoken by more than 5 ethnic groups who variously are of Muslim, Christian, and animist faith. Life expectancy is 47-51 years. GDP is 331 billion, growing at a rate of 2%. Per capita income is 37 3. The country's natural resources potentially include oil. Peanuts, rice, millet, sorghum, fish, palm kernels, vegetables, livestock, forestry, construction, brewing, soft drinks, machinery assembly, wood and metal working, and clothing are areas of economic production. Textiles, foodstuffs, machinery, and transportation equipment are imported, and re-exported goods, peanuts, palm kernels, fish, and other domestic products are exported. In-depth information is also given on the people and history, government and principal officials, political conditions, the economy, defense, foreign relations, relations with the U.S., and names of principal U.S. officials in the country.

  16. Bio-efficacy of new long-lasting insecticide-treated bed nets against Anopheles funestus and Anopheles gambiae from central and northern Mozambique.

    PubMed

    Abílio, Ana Paula; Marrune, Pelágio; de Deus, Nilsa; Mbofana, Francisco; Muianga, Pedro; Kampango, Ayubo

    2015-09-17

    Long-lasting insecticide-treated nets (LLINs) are one of the main methods used for controlling malaria transmission in Mozambique. The proliferation of several types of LLINs and the re-emergence of insecticide resistance in the local vector populations poses challenges to the local malaria control programme on selecting suitable insecticide-based vector control products. Therefore, this study evaluated the insecticide susceptibility and bio-efficacy of selected new LLINs against wild populations of Anopheles funestus sensu lato and A. gambiae s.l. from Northern and Central Mozambique. The study also investigated whether the insecticide contents on the LINNs fabrics were within the WHOPES recommended target range. The susceptibility of 2-5 day old wild female A. funestus and A. gambiae sensu stricto against the major classes of insecticides used for vector control, viz: deltamethrin (0.05 %), permethrin (0.75 %), propoxur (0.1 %), bendiocarb (0.1 %) and DDT (4 %), was determined using WHO cylinder susceptibility tests. WHO cone bioassays were conducted to determine the bio-efficacy of both pyrethroid-only LLINs (Olyset(®), Permanet 2.0(®), NetProtect(®) and Interceptor(®)) and, Permanet 3.0(®) a combination LLIN against A. funestus s.s, from Balama, Mocuba and Milange districts, respectively. The bio-efficacy of LLINs against the insectary-susceptible A. arabiensis (Durban strain) was assessed, as well. Untreated bed net swatches were used as negative controls. Chemical analyses, by high performance liquid chromatography, were undertaken to assess whether the insecticide contents on the LLINs fabrics fell within recommended target dose ranges. The frequency of kdr gene mutations was determined from a random sample of A. gambiae s.s. from both WHO susceptibility and cone bioassay experiments. Anopheles funestus from Balama district showed resistance to deltamethrin and possible resistance to permethrin, propoxur and bendiocarb, whilst A. gambiae from

  17. Geographical and genospecies distribution of Borrelia burgdorferi sensu lato DNA detected in humans in the USA.

    PubMed

    Clark, Kerry L; Leydet, Brian F; Threlkeld, Clifford

    2014-05-01

    The present study investigated the cause of illness in human patients primarily in the southern USA with suspected Lyme disease based on erythema migrans-like skin lesions and/or symptoms consistent with early localized or late disseminated Lyme borreliosis. The study also included some patients from other states throughout the USA. Several PCR assays specific for either members of the genus Borrelia or only for Lyme group Borrelia spp. (Borrelia burgdorferi sensu lato), and DNA sequence analysis, were used to identify Borrelia spp. DNA in blood and skin biopsy samples from human patients. B. burgdorferi sensu lato DNA was found in both blood and skin biopsy samples from patients residing in the southern states and elsewhere in the USA, but no evidence of DNA from other Borrelia spp. was detected. Based on phylogenetic analysis of partial flagellin (flaB) gene sequences, strains that clustered separately with B. burgdorferi sensu stricto, Borrelia americana or Borrelia andersonii were associated with Lyme disease-like signs and symptoms in patients from the southern states, as well as from some other areas of the country. Strains most similar to B. burgdorferi sensu stricto and B. americana were found most commonly and appeared to be widely distributed among patients residing throughout the USA. The study findings suggest that human cases of Lyme disease in the southern USA may be more common than previously recognized and may also be caused by more than one species of B. burgdorferi sensu lato. This study provides further evidence that B. burgdorferi sensu stricto is not the only species associated with signs and/or symptoms consistent with Lyme borreliosis in the USA.

  18. Phylogenetic affiliations of members of the heterogeneous lichen-forming fungi of the genus Lecidea sensu Zahlbruckner (Lecanoromycetes, Ascomycota).

    PubMed

    Schmull, Michaela; Miadlikowska, Jolanta; Pelzer, Monika; Stocker-Wörgötter, Elfie; Hofstetter, Valerie; Fraker, Emily; Hodkinson, Brendan P; Reeb, Valerie; Kukwa, Martin; Lumbsch, H Thorsten; Kauff, Frank; Lutzoni, François

    2011-01-01

    The genus Lecidea Ach. sensu lato (sensu Zahlbruckner) includes almost 1200 species, out of which only 100 species represent Lecidea sensu stricto (sensu Hertel). The systematic position of the remaining species is mostly unsettled but anticipated to represent several unrelated lineages within Lecanoromycetes. This study attempts to elucidate the phylogenetic placement of members of this heterogeneous group of lichen-forming fungi and to improve the classification and phylogeny of Lecanoromycetes. Twenty-five taxa of Lecidea sensu lato and 22 putatively allied species were studied in a broad selection of 268 taxa, representing 48 families of Lecanoromycetes. Six loci, including four ribosomal and two protein-coding genes for 315- and 209-OTU datasets were subjected to maximum likelihood and Bayesian analyses. The resulting well supported phylogenetic relationships within Lecanoromycetes are in agreement with published phylogenies, but the addition of new taxa revealed putative rearrangements of several families (e.g. Catillariaceae, Lecanoraceae, Lecideaceae, Megalariaceae, Pilocarpaceae and Ramalinaceae). As expected, species of Lecidea sensu lato and putatively related taxa are scattered within Lecanoromycetidae and beyond, with several species nested in Lecanoraceae and Pilocarpaceae and others placed outside currently recognized families in Lecanorales and orders in Lecanoromycetidae. The phylogenetic affiliations of Schaereria and Strangospora are outside Lecanoromycetidae, probably with Ostropomycetidae. All species referred to as Lecidea sensu stricto based on morphology (including the type species, Lecidea fuscoatra [L.] Ach.) form, with Porpidia species, a monophyletic group with high posterior probability outside Lecanorales, Peltigerales and Teloschistales, in Lecanoromycetidae, supporting the recognition of order Lecideales Vain. in this subclass. The genus name Lecidea must be redefined to apply only to Lecidea sensu stricto and to include at least

  19. Molecular and Pathogenic Characterization of Borrelia burgdorferi Sensu Lato Isolates from Spain

    PubMed Central

    Escudero, Raquel; Barral, Marta; Pérez, Azucena; Vitutia, M. Mar; García-Pérez, Ana L.; Jiménez, Santos; Sellek, Ricela E.; Anda, Pedro

    2000-01-01

    Fifteen Borrelia burgdorferi sensu lato isolates from questing ticks and skin biopsy specimens from erythema migrans patients in three different areas of Spain were characterized. Four different genospecies were found (nine Borrelia garinii, including the two human isolates, three B. burgdorferi sensu stricto, two B. valaisiana, and one B. lusitaniae), showing a diverse spectrum of B. burgdorferi sensu lato species. B. garinii isolates were highly variable in terms of pulsed-field gel electrophoresis pattern and OspA serotype, with four of the seven serotypes described. One of the human isolates was OspA serotype 5, the same found in four of seven tick isolates. The second human isolate was OspA serotype 3, which was not present in ticks from the same area. Seven B. garinii isolates were able to disseminate through the skin of C3H/HeN mice and to cause severe inflammation of joints. One of the two B. valaisiana isolates also caused disease in mice. Only one B. burgdorferi sensu stricto isolate was recovered from the urinary bladder. One isolate each of B. valaisiana and B. lusitaniae were not able to disseminate through the skin of mice or to infect internal organs. In summary, there is substantial diversity in the species and in the pathogenicity of B. burgdorferi sensu lato in areas in northern Spain where Lyme disease is endemic. PMID:11060064

  20. Fourier transform infrared spectroscopy of DNA from Borrelia burgdorferi sensu lato and Ixodes ricinus ticks

    NASA Astrophysics Data System (ADS)

    Muntean, Cristina M.; Stefan, Razvan; Bindea, Maria; Cozma, Vasile

    2013-06-01

    In this work we present a method for detection of motile and immotile Borrelia burgdorferi genomic DNA, in relation with infectious and noninfectious spirochetes. An FT-IR study of DNA isolated from B. burgdorferi sensu lato strains and from positive and negative Ixodes ricinus ticks, respectively, is reported. Motile bacterial cells from the species B. burgdorferi sensu stricto, Borrelia garinii and Borrelia afzelii were of interest. Also, FT-IR absorbance spectra of DNA from immotile spirochetes of B. burgdorferi sensu stricto, in the absence and presence of different antibiotics (doxycycline, erythromycin, gentamicin, penicillin V or phenoxymethylpenicillin, tetracycline, respectively) were investigated. FT-IR spectra, providing a high molecular structural information, have been analyzed in the wavenumber range 400-1800 cm-1. FT-IR signatures, spectroscopic band assignments and structural interpretations of these DNAs are reported. Spectral differences between FT-IR absorbances of DNAs from motile bacterial cells and immotile spirochetes, respectively, have been found. Particularly, alterations of the sugar-phosphate B-form chain in the case of DNA from Borrelia immotile cells, as compared with DNA from B. burgdorferi sensu lato motile cells have been observed. Based on this work, specific B. burgdorferi sensu lato and I. ricinus DNA-ligand interactions, respectively, might be further investigated using Fourier transform infrared spectroscopy.

  1. Identification of Candida parapsilosis Sensu Lato in Pediatric Patients and Antifungal Susceptibility Testing.

    PubMed

    Cattana, Maria Emilia; Dudiuk, Catiana; Fernández, Mariana; Rojas, Florencia; Alegre, Liliana; Córdoba, Susana; Garcia-Effron, Guillermo; Giusiano, Gustavo

    2017-07-01

    A total of 59 Candida parapsilosis sensu stricto and 1 Candida orthopsilosis recovered from catheters and blood cultures of pediatric patients from the northeastern region of Argentina were studied. Susceptibility to azoles, amphotericin B, and echinocandins was tested by the broth microdilution method. According to CLSI clinical breakpoints, >91% of the strains were azole susceptible, whereas 15% showed high amphotericin B MICs. Copyright © 2017 American Society for Microbiology.

  2. Differential effects of inbreeding and selection on male reproductive phenotype associated with the colonization and laboratory maintenance of Anopheles gambiae.

    PubMed

    Baeshen, Rowida; Ekechukwu, Nkiru E; Toure, Mahamoudou; Paton, Doug; Coulibaly, Mamadou; Traoré, Sékou F; Tripet, Frédéric

    2014-01-13

    Effective mating between laboratory-reared males and wild females is paramount to the success of vector control strategies aiming to decrease disease transmission via the release of sterile or genetically modified male mosquitoes. However mosquito colonization and laboratory maintenance have the potential to negatively affect male genotypic and phenotypic quality through inbreeding and selection, which in turn can decrease male mating competitiveness in the field. To date, very little is known about the impact of those evolutionary forces on the reproductive biology of mosquito colonies and how they ultimately affect male reproductive fitness. Here several male reproductive physiological traits likely to be affected by inbreeding and selection following colonization and laboratory rearing were examined. Sperm length, and accessory gland and testes size were compared in male progeny from field-collected females and laboratory strains of Anopheles gambiae sensu stricto colonized from one to over 25 years ago. These traits were also compared in the parental and sequentially derived, genetically modified strains produced using a two-phase genetic transformation system. Finally, genetic crosses were performed between strains in order to distinguish the effects of inbreeding and selection on reproductive traits. Sperm length was found to steadily decrease with the age of mosquito colonies but was recovered in refreshed strains and crosses between inbred strains therefore incriminating inbreeding costs. In contrast, testes size progressively increased with colony age, whilst accessory gland size quickly decreased in males from colonies of all ages. The lack of heterosis in response to crossing and strain refreshing in the latter two reproductive traits suggests selection for insectary conditions. These results show that inbreeding and selection differentially affect reproductive traits in laboratory strains overtime and that heterotic 'supermales' could be used to rescue

  3. Differential effects of inbreeding and selection on male reproductive phenotype associated with the colonization and laboratory maintenance of Anopheles gambiae

    PubMed Central

    2014-01-01

    Background Effective mating between laboratory-reared males and wild females is paramount to the success of vector control strategies aiming to decrease disease transmission via the release of sterile or genetically modified male mosquitoes. However mosquito colonization and laboratory maintenance have the potential to negatively affect male genotypic and phenotypic quality through inbreeding and selection, which in turn can decrease male mating competitiveness in the field. To date, very little is known about the impact of those evolutionary forces on the reproductive biology of mosquito colonies and how they ultimately affect male reproductive fitness. Methods Here several male reproductive physiological traits likely to be affected by inbreeding and selection following colonization and laboratory rearing were examined. Sperm length, and accessory gland and testes size were compared in male progeny from field-collected females and laboratory strains of Anopheles gambiae sensu stricto colonized from one to over 25 years ago. These traits were also compared in the parental and sequentially derived, genetically modified strains produced using a two-phase genetic transformation system. Finally, genetic crosses were performed between strains in order to distinguish the effects of inbreeding and selection on reproductive traits. Results Sperm length was found to steadily decrease with the age of mosquito colonies but was recovered in refreshed strains and crosses between inbred strains therefore incriminating inbreeding costs. In contrast, testes size progressively increased with colony age, whilst accessory gland size quickly decreased in males from colonies of all ages. The lack of heterosis in response to crossing and strain refreshing in the latter two reproductive traits suggests selection for insectary conditions. Conclusions These results show that inbreeding and selection differentially affect reproductive traits in laboratory strains overtime and that

  4. Decline in frequency of the 2La chromosomal inversion in Anopheles gambiae (s.s.) in Western Kenya: correlation with increase in ownership of insecticide-treated bed nets.

    PubMed

    Matoke-Muhia, Damaris; Gimnig, John E; Kamau, Luna; Shililu, Josephat; Bayoh, M Nabie; Walker, Edward D

    2016-06-10

    The 2La chromosomal inversion, a genetic polymorphism in An. gambiae (sensu stricto) (s.s.), is associated with adaptation to microclimatic differences in humidity and desiccation resistance and mosquito behaviors. Ownership of insecticide-treated bed nets (ITNs) for malaria control has increased markedly in western Kenya in the last 20 years. An increase in the frequency of ITNs indoors could select against house entering or indoor resting of Anopheles mosquitoes. Thus, the frequency of the 2La inversion is postulated to change in An. gambiae (s.s.) with the increase of ITN ownership over time. Anopheles gambiae mosquitoes were sampled between 1994 and 2011 using pyrethrum knockdown, bednet traps and human landing catches (HLC) from Asembo and Seme, western Kenya. The 2La inversion was detected by a PCR assay with primers designed for proximal breakpoints of the 2La/a and 2L+(a)/+(a) chromosomal conformation. Mosquitoes were tested for malaria parasite infection by sporozoite ELISA. The frequency of the 2La chromosomal inversion declined from 100 % of all chromosomes in 1994 to 17 % in 2005 and remained low through 2011 (21 %). ITN ownership increased from 0 to > 90 % of houses in the study area during this interval. The decline in the frequency of the 2La chromosomal inversion was significantly, negatively correlated with year (r = -0.93) and with increase in ITN ownership (r = -0.96). The frequency of the homo- and heterokaryotypes departed significantly from Hardy-Weinberg equilibrium, suggesting that 2La/a karyotype was under selection, earlier in its favor and later, against it. Precipitation and maximum monthly temperature did not vary over time, therefore there was no trend in climate that could account for the decline. There was no significant difference in frequency of the 2La inversion in An. gambiae (s.s.) females sampled indoors or outdoors in HCL in 2011, nor was there an association between the 2La inversion and infection with Plasmodium

  5. Molecular phylogeny of the megadiverse insect infraorder Bibionomorpha sensu lato (Diptera)

    PubMed Central

    Kaspřák, David; Mantič, Michal; Fitzgerald, Scott; Ševčíková, Tereza; Tóthová, Andrea; Jaschhof, Mathias

    2016-01-01

    The phylogeny of the insect infraorder Bibionomorpha (Diptera) is reconstructed based on the combined analysis of three nuclear (18S, 28S, CAD) and three mitochondrial (12S, 16S, COI) gene markers. All the analyses strongly support the monophyly of Bibionomorpha in both the narrow (sensu stricto) and the broader (sensu lato) concepts. The major lineages of Bibionomorpha sensu lato (Sciaroidea, Bibionoidea, Anisopodoidea, and Scatopsoidea) and most of the included families are supported as monophyletic groups. Axymyiidae was not found to be part of Bibionomorpha nor was it found to be its sister group. Bibionidae was paraphyletic with respect to Hesperinidae and Keroplatidae was paraphyletic with respect to Lygistorrhinidae. The included Sciaroidea incertae sedis (except Ohakunea Edwards) were found to belong to one clade, but the relationships within this group and its position within Sciaroidea require further study. PMID:27781163

  6. Molecular Identification and Analysis of Borrelia burgdorferi Sensu Lato in Lizards in the Southeastern United States

    PubMed Central

    Clark, Kerry; Hendricks, Amanda; Burge, David

    2005-01-01

    Lyme borreliosis (LB) group spirochetes, collectively known as Borrelia burgdorferi sensu lato, are distributed worldwide. Wild rodents are acknowledged as the most important reservoir hosts. Ixodes scapularis is the primary vector of B. burgdorferi sensu lato in the eastern United States, and in the southeastern United States, the larvae and nymphs mostly parasitize certain species of lizards. The primary aim of the present study was to determine whether wild lizards in the southeastern United States are naturally infected with Lyme borreliae. Blood samples obtained from lizards in Florida and South Carolina were tested for the presence of LB spirochetes primarily by using B. burgdorferi sensu lato-specific PCR assays that amplify portions of the flagellin (flaB), outer surface protein A (ospA), and 66-kDa protein (p66) genes. Attempts to isolate spirochetes from a small number of PCR-positive lizards failed. However, PCR amplification and sequence analysis of partial flaB, ospA, and p66 gene fragments confirmed numerous strains of B. burgdorferi sensu lato, including Borrelia andersonii, Borrelia bissettii, and B. burgdorferi sensu stricto, in blood from lizards from both states. B. burgdorferi sensu lato DNA was identified in 86 of 160 (54%) lizards representing nine species and six genera. The high infection prevalence and broad distribution of infection among different lizard species at different sites and at different times of the year suggest that LB spirochetes are established in lizards in the southeastern United States. PMID:15870353

  7. Pyrethroid resistance in Anopheles gambiae leads to increased susceptibility to the entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana

    PubMed Central

    2010-01-01

    Background Entomopathogenic fungi are being investigated as a new mosquito control tool because insecticide resistance is preventing successful mosquito control in many countries, and new methods are required that can target insecticide-resistant malaria vectors. Although laboratory studies have previously examined the effects of entomopathogenic fungi against adult mosquitoes, most application methods used cannot be readily deployed in the field. Because the fungi are biological organisms it is important to test potential field application methods that will not adversely affect them. The two objectives of this study were to investigate any differences in fungal susceptibility between an insecticide-resistant and insecticide-susceptible strain of Anopheles gambiae sensu stricto, and to test a potential field application method with respect to the viability and virulence of two fungal species Methods Pieces of white polyester netting were dipped in Metarhizium anisopliae ICIPE-30 or Beauveria bassiana IMI391510 mineral oil suspensions. These were kept at 27 ± 1°C, 80 ± 10% RH and the viability of the fungal conidia was recorded at different time points. Tube bioassays were used to infect insecticide-resistant (VKPER) and insecticide-susceptible (SKK) strains of An. gambiae s.s., and survival analysis was used to determine effects of mosquito strain, fungus species or time since fungal treatment of the net. Results The resistant VKPER strain was significantly more susceptible to fungal infection than the insecticide-susceptible SKK strain. Furthermore, B. bassiana was significantly more virulent than M. anisopliae for both mosquito strains, although this may be linked to the different viabilities of these fungal species. The viability of both fungal species decreased significantly one day after application onto polyester netting when compared to the viability of conidia remaining in suspension. Conclusions The insecticide-resistant mosquito strain was susceptible

  8. Molecular Typing of Borrelia burgdorferi Sensu Lato: Taxonomic, Epidemiological, and Clinical Implications

    PubMed Central

    Wang, Guiqing; van Dam, Alje P.; Schwartz, Ira; Dankert, Jacob

    1999-01-01

    Borrelia burgdorferi sensu lato, the spirochete that causes human Lyme borreliosis (LB), is a genetically and phenotypically divergent species. In the past several years, various molecular approaches have been developed and used to determine the phenotypic and genetic heterogeneity within the LB-related spirochetes and their potential association with distinct clinical syndromes. These methods include serotyping, multilocus enzyme electrophoresis, DNA-DNA reassociation analysis, rRNA gene restriction analysis (ribotyping), pulsed-field gel electrophoresis, plasmid fingerprinting, randomly amplified polymorphic DNA fingerprinting analysis, species-specific PCR and PCR-based restriction fragment length polymorphism (RFLP) analysis, and sequence analysis of 16S rRNA and other conserved genes. On the basis of DNA-DNA reassociation analysis, 10 different Borrelia species have been described within the B. burgdorferi sensu lato complex: B. burgdorferi sensu stricto, Borrelia garinii, Borrelia afzelii, Borrelia japonica, Borrelia andersonii, Borrelia valaisiana, Borrelia lusitaniae, Borrelia tanukii, Borrelia turdi, and Borrelia bissettii sp. nov. To date, only B. burgdorferi sensu stricto, B. garinii, and B. afzelii are well known to be responsible for causing human disease. Different Borrelia species have been associated with distinct clinical manifestations of LB. In addition, Borrelia species are differentially distributed worldwide and may be maintained through different transmission cycles in nature. In this paper, the molecular methods used for typing of B. burgdorferi sensu lato are reviewed. The current taxonomic status of B. burgdorferi sensu lato and its epidemiological and clinical implications, especiallly correlation between the variable clinical presentations and the infecting Borrelia species, are discussed in detail. PMID:10515907

  9. Seed dispersal and predation of Buchenavia tomentosa Eichler (Combretaceae) in a Cerrado sensu stricto, midwest Brazil.

    PubMed

    Farias, J; Sanchez, M; Abreu, M F; Pedroni, F

    2015-11-01

    The ecology of seed dispersal is critical to understand the patterns of distribution and abundance of plant species. We investigated seed dispersal aspects associated with the high abundance of Buchenavia tomentosa in the Serra Azul State Park (PESA). We estimated fruit production and conducted fruit removal experiments. We carried out diurnal and nocturnal observations on frugivory as well as germination tests. Fruiting occurred in the dry season and totaled 1,365,015 ± 762,670 fruits.ha-1. B. tomentosa fruits were utilized by eight animal species. The lowland tapir (Tapirus terrestris) was considered the main seed disperser. Leafcutter ants (Atta laevigata and Atta sexdens) participated in the seed cleaning and occasionally dispersed seeds. The beetle Amblycerus insuturatus, blue-and-yellow macaw (Ara ararauna) and red-and-green macaw (Ara chloropterus) were considered pre-dispersal seed predators. The seeds manually cleaned presented higher germination rate (100%) and speed index (4.2 seeds.d-1) than that of seeds with pulp. Germination of seeds found in tapirs'feces was 40%, while for the seeds without pulp it was 25%. The high abundance of B. tomentosa in the cerrado of PESA may be due to massive fruit production, low rates of seed predation, and efficient seed dispersal by tapirs, occurring before the rains which promote germination and recruitment of this species.

  10. Tenuipalpus sensu stricto (Acari: Tenuipalpidae) from Brazil, with ontogeny and a key to the known species

    USDA-ARS?s Scientific Manuscript database

    The Cerrado is the second largest Brazilian biome, and is considered to be a “hotspot” due the great concentration of en-demic species and high rate of deforestation. Surveys of the mite fauna present in this biome have revealed a great number of new species. In this paper, we describe Tenuipalpus s...

  11. Genome Sequencing and Comparative Analysis of the Biocontrol Agent Trichoderma harzianum sensu stricto TR274

    SciTech Connect

    Steindorff, Andrei S.; Noronha, Elilane F.; Ulhoa, Cirano J.; Kuo, Alan; Salamov, Asaf A.; Haridas, Sajeet; Riley, Robert W.; Druzhinina, Irina S.; Kubicek, Christian P.; Grigoriev, Igor V.

    2015-03-17

    Biological control is a complex process which requires many mechanisms and a high diversity of biochemical pathways. The species of Trichoderma harzianum are well known for their biocontrol activity against many plant pathogens. To gain new insights into the biocontrol mechanism used by T. harzianum, we sequenced the isolate TR274 genome using Illumina. The assembly was performed using AllPaths-LG with a maximum coverage of 100x. The assembly resulted in 2282 contigs with a N50 of 37033bp. The genome size generated was 40.8 Mb and the GC content was 47.7%, similar to other Trichoderma genomes. Using the JGI Annotation Pipeline we predicted 13,932 genes with a high transcriptome support. CEGMA tests suggested 100% genome completeness and 97.9% of RNA-SEQ reads were mapped to the genome. The phylogenetic comparison using orthologous proteins with all Trichoderma genomes sequenced at JGI, corroborates the Trichoderma (T. asperellum and T. atroviride), Longibrachiatum (T. reesei and T. longibrachiatum) and Pachibasium (T. harzianum and T. virens) section division described previously. The comparison between two Trichoderma harzianum species suggests a high genome similarity but some strain-specific expansions. Analyses of the secondary metabolites, CAZymes, transporters, proteases, transcription factors were performed. The Pachybasium section expanded virtually all categories analyzed compared with the other sections, specially Longibrachiatum section, that shows a clear contraction. These results suggests that these proteins families have an important role in their respective phenotypes. Future analysis will improve the understanding of this complex genus and give some insights about its lifestyle and the interactions with the environment.

  12. New Hybrids between Saccharomyces Sensu Stricto Yeast Species Found among Wine and Cider Production Strains

    PubMed Central

    Masneuf, Isabelle; Hansen, Jørgen; Groth, Casper; Piskur, Jure; Dubourdieu, Denis

    1998-01-01

    Two yeast isolates, a wine-making yeast first identified as a Mel+ strain (ex. S. uvarum) and a cider-making yeast, were characterized for their nuclear and mitochondrial genomes. Electrophoretic karyotyping analyses, restriction fragment length polymorphism maps of PCR-amplified MET2 gene fragments, and the sequence analysis of a part of the two MET2 gene alleles found support the notion that these two strains constitute hybrids between Saccharomyces cerevisiae and Saccharomyces bayanus. The two hybrid strains had completely different restriction patterns of mitochondrial DNA as well as different sequences of the OLI1 gene. The sequence of the OLI1 gene from the wine hybrid strain appeared to be the same as that of the S. cerevisiae gene, whereas the OLI1 gene of the cider hybrid strain is equally divergent from both putative parents, S. bayanus and S. cerevisiae. Some fermentative properties were also examined, and one phenotype was found to reflect the hybrid nature of these two strains. The origin and nature of such hybridization events are discussed. PMID:9758815

  13. New hybrids between Saccharomyces sensu stricto yeast species found among wine and cider production strains.

    PubMed

    Masneuf, I; Hansen, J; Groth, C; Piskur, J; Dubourdieu, D

    1998-10-01

    Two yeast isolates, a wine-making yeast first identified as a Mel+ strain (ex. S. uvarum) and a cider-making yeast, were characterized for their nuclear and mitochondrial genomes. Electrophoretic karyotyping analyses, restriction fragment length polymorphism maps of PCR-amplified MET2 gene fragments, and the sequence analysis of a part of the two MET2 gene alleles found support the notion that these two strains constitute hybrids between Saccharomyces cerevisiae and Saccharomyces bayanus. The two hybrid strains had completely different restriction patterns of mitochondrial DNA as well as different sequences of the OLI1 gene. The sequence of the OLI1 gene from the wine hybrid strain appeared to be the same as that of the S. cerevisiae gene, whereas the OLI1 gene of the cider hybrid strain is equally divergent from both putative parents, S. bayanus and S. cerevisiae. Some fermentative properties were also examined, and one phenotype was found to reflect the hybrid nature of these two strains. The origin and nature of such hybridization events are discussed.

  14. Camarosporium arezzoensis on Cytisus sp., an addition to sexual state of Camarosporium sensu stricto.

    PubMed

    Tibpromma, Saowaluck; Wijayawardene, Nalin N; Manamgoda, Dimuthu S; Boonmee, Saranyaphat; Wanasinghe, Dhanushka N; Camporesi, Erio; Yang, Jun-Bo; Hyde, Kevin D

    2016-01-01

    During a study of saprobic fungi from Bagno di Cetica Province, Italy, we collected a pleosporoid ascomycete on stems of Cytisus sp. In morphology, our collection is similar to Cucurbitaria species, but molecular analysis of SSU, LSU and ITS genes reveals it can be referred to Camarosporium. In this study we compare all other Cucurbitaria species from Cytisus sp. and based on both morphology and molecular data, we introduce our collection as a new species in Camarosporium viz. C. arezzoensis.

  15. Molecular and metabolic characterization of cold-tolerant alpine soil Pseudomonas sensu stricto.

    PubMed

    Meyer, A F; Lipson, D A; Martin, A P; Schadt, C W; Schmidt, S K

    2004-01-01

    Alpine soils undergo dramatic temporal changes in their microclimatic properties, suggesting that the bacteria there encounter uncommon shifting selection gradients. Pseudomonads constitute important members of the alpine soil community. In order to characterize the alpine Pseudomonas community and to assess the impact of shifting selection on this community, we examined the ability of cold-tolerant Pseudomonas isolates to grow on a variety of carbon sources, and we determined their phylogenetic relationships based on 16S ribosomal DNA sequencing. We found a high prevalence of Pseudomonas in our soil samples, and isolates from these soils exhibited extensive metabolic diversity. In addition, our data revealed that many of our isolates form a unique cold-adapted clade, representatives of which are also found in the Swedish tundra and Antarctica. Our data also show a lack of concordance between the metabolic properties and 16S phylogeny, indicating that the metabolic diversity of these organisms cannot be predicted by phylogeny.

  16. Cases of Echinococcus granulosus Sensu Stricto Isolated from Polish Patients: Imported or Indigenous?

    PubMed

    Dybicz, Monika; Borkowski, Piotr Karol; Dąbrowska, Julia; Chomicz, Lidia

    2015-01-01

    The cases of nine Polish patients with diagnosed cystic echinococcosis (CE) were examined. A total of nine isolates obtained postoperatively were investigated using PCR and sequencing. The mitochondrial region of nad1 gene was amplified. This PCR and sequencing analysis revealed the presence of Echinococcus canadensis G7 in seven patients and E. granulosus G1 in two patients. These data demonstrate that E. canadensis is the predominant causative agent of human cystic echinococcosis in Poland. E. granulosus G1 detection in Polish patients suggests that the parasite was imported; however it does not exclude the possibility that these cases could have been of Polish origin.

  17. Cases of Echinococcus granulosus Sensu Stricto Isolated from Polish Patients: Imported or Indigenous?

    PubMed Central

    Dybicz, Monika; Borkowski, Piotr Karol; Dąbrowska, Julia; Chomicz, Lidia

    2015-01-01

    The cases of nine Polish patients with diagnosed cystic echinococcosis (CE) were examined. A total of nine isolates obtained postoperatively were investigated using PCR and sequencing. The mitochondrial region of nad1 gene was amplified. This PCR and sequencing analysis revealed the presence of Echinococcus canadensis G7 in seven patients and E. granulosus G1 in two patients. These data demonstrate that E. canadensis is the predominant causative agent of human cystic echinococcosis in Poland. E. granulosus G1 detection in Polish patients suggests that the parasite was imported; however it does not exclude the possibility that these cases could have been of Polish origin. PMID:26491683

  18. First report of Borrelia burgdorferi sensu lato in two threatened carnivores: the Marbled polecat, Vormela peregusna and the European mink, Mustela lutreola (Mammalia: Mustelidae)

    PubMed Central

    2012-01-01

    Background Lyme disease is a widespread cosmopolitan zoonosis caused by species belonging to the genus Borrelia. It is transmitted from animal reservoir hosts to humans through hard - ticks of genus Ixodes which are vectors of the disease. Case presentation Borrelia burgdorferi sensu lato infection was identified in a marbled polecat, Vormela peregusna, and two European minks, Mustela lutreola, from Romania, by PCR. RFLP revealed the presence of a single genospecies, Borrelia burgdorferi sensu stricto. Conclusions This is the first report of the Lyme disease spirochetes in the two mentioned hosts. PMID:22901862

  19. Expression Profiles of Toll-Like Receptors in the Differentiation of an Infection with Borrelia burgdorferi Sensu Lato Spirochetes.

    PubMed

    Dudek, Slawomir; Ziółko, Ewa; Kimsa-Dudek, Magdalena; Solarz, Krzysztof; Mazurek, Urszula; Wierzgoń, Aleksander; Kokot, Teresa; Muc-Wierzgoń, Małgorzata

    2017-04-01

    The similarity of Lyme borreliosis to other diseases and its complex pathogenesis present diagnostic and therapeutic difficulties. The changes that occur at the cellular and molecular levels after a Borrelia sp. infection still remain poorly understood. Therefore, the present study focused on the expression of TLR and TLR-signaling genes in human dermal fibroblasts in the differentiation of an infection with Borrelia burgdorferi sensu lato spirochetes. Normal human dermal fibroblasts were cultured with the spirochetes of Borrelia burgdorferi sensu stricto, Borrelia afzelii and Borrelia garinii. Total RNA was extracted from the cells using TRIzol reagent. The analysis of the expression profiles of TLRs and TLR-related genes was performed using commercially available oligonucleotide microarrays of HG-U133A. The GeneSpring 12.0 platform and significance analysis of microarrays were used for the statistical analysis of microarray data. The analyses using the oligonucleotide microarray and QRT-PCR techniques permitted to identify the genes encoding TLR4 and TLR6 as specific for infection with B. afzelii and B. burgdorferi sensu stricto. In turn, TLR3 was only characteristic for an infection with B. burgdorferi sensu stricto. There were no changes in the TLR gene expression after infection with B. garinii. Our findings confirm that Borrelia has a major effect on fibroblast gene expression. Further characterization of changes in gene expression may lead to valuable insights into the role of the toll-like receptor in the pathogenesis of Lyme disease and may provide guidelines for the development of diagnostic markers for an infection with a particular Borrelia genospecies. Moreover, this will help to identify better treatment strategies for Lyme disease.

  20. C-reactive protein, Neopterin and Beta2 microglobulin levels pre and post TB treatment in The Gambia.

    PubMed

    Mendy, Joseph; Togun, Toyin; Owolabi, Olumuyiwa; Donkor, Simon; Ota, Martin O C; Sutherland, Jayne S

    2016-03-08

    Tuberculosis is one of the leading causes of morbidity and mortality in developing countries. Analysis of the host immune response may help with generating point-of-care tests for personalised monitoring. Thus, the aim of this study was to assess the relationship between immune activation markers: C-reactive protein (CRP), Beta2 microglobulin (B2M) and Neopterin, disease severity prior to treatment and response to therapy in adult pulmonary TB patients. HIV negative adult pulmonary TB index cases (n = 91) were recruited from the TB clinic at MRC, The Gambia. Plasma samples were collected at enrolment and at 2 and 6 months following TB treatment initiation. An enzyme linked immunosorbent assay (ELISA) was performed for evaluation of CRP, B2M and Neopterin levels and correlated with clinical and microbiological parameters including strain of infection. Disease severity was determined using Chest X-ray (CXR), Body Mass Index (BMI) and sputum smear grade. Plasma levels of all three markers were highly elevated in patients at recruitment and declined significantly during TB therapy. No correlation with disease severity was seen at recruitment. CRP showed the most significant decrease by 2 months of treatment (p < 0.0001) whereas levels of B2M and Neopterin showed little change by 2 months but a significant decrease by 6 months of treatment (p = 0.0002 and p < 0.0001 respectively). At recruitment, B2M levels were significantly higher in subjects infected with Mycobacterium africanum (Maf) compared with those infected with Mycobacterium tuberculosis sensu stricto (Mtb) (p = 0.0075). In addition, while CRP and Neopterin showed a highly significant decline post-treatment regardless of strain (p < 0.0001 for all), B2M showed differential decline depending on strain (p = 0.0153 for Mtb and p = 0.0048 for Maf) and levels were still significantly higher at 6 months in Maf compared to Mtb infected subjects (p = 0.0051). Our findings suggest that activation markers, particularly

  1. Epidemiology and echinocandin susceptibility of Candida parapsilosis sensu lato species isolated from bloodstream infections at a Spanish university hospital

    PubMed Central

    Garcia-Effron, Guillermo; Canton, Emilia; Pemán, Javier; Dilger, Amanda; Romá, Eva; Perlin, David S.

    2012-01-01

    Objectives The aims of this work were to study the epidemiological profiles, differences in echinocandin susceptibilities and clinical relevance of the Candida parapsilosis sensu lato species isolated from proven fungaemia cases at La Fe University Hospital of Valencia (Spain) from 1995 to 2007. Results The prevalence of these species was: C. parapsilosis sensu stricto, 74.4%; Candida orthopsilosis, 23.54%; and Candida metapsilosis, 2.05%. The incidence of the species complex as agents of fungaemia remained stationary until 2005 and doubled in 2006. The incidence of C. orthopsilosis showed an increasing trend during the study period, while C. parapsilosis sensu stricto incidence diminished. Also, an important epidemiological change was observed starting in 2004, when 86.5% of the C. parapsilosis sensu lato strains were found in adult patients, while before that year only 13.5% of the isolates were found in this population. Conclusions Echinocandin drug susceptibility testing using the CLSI M27-A3 document showed a wide range of MIC values (0.015–4 mg/L), with micafungin being the most potent in vitro inhibitor followed by anidulafungin and caspofungin (MIC geometric mean of 0.68, 0.74 and 0.87 mg/L, respectively). C. metapsilosis was the most susceptible species of the complex to anidulafungin and micafungin in vitro (MIC50 for anidulafungin and micafungin: 0.06 mg/L), while there were no differences between C. parapsilosis sensu lato species when caspofungin MIC50s were compared (MIC50 1.00 mg/L). Differences in caspofungin in vitro susceptibility were observed between the different clinical service departments of La Fe Hospital. PMID:22868644

  2. Molecular Typing of Borrelia burgdorferi Sensu Lato by Randomly Amplified Polymorphic DNA Fingerprinting Analysis

    PubMed Central

    Wang, Guiqing; van Dam, Alje P.; Spanjaard, Lodewijk; Dankert, Jacob

    1998-01-01

    To study whether pathogenic clusters of Borrelia burgdorferi sensu lato strains occur, we typed 136 isolates, cultured from specimens from patients (n = 49) with various clinical entities and from ticks (n = 83) or dogs (n = 4) from different geographic regions, by randomly amplified polymorphic DNA (RAPD) fingerprinting with four arbitrary primers. The RAPD patterns were reproducible up to the 95% similarity level as shown in duplicate experiments. In these experiments the purified DNAs prepared on different days, from different colonies, and after various passages were used as templates. With an intergroup difference of 55%, the 136 strains could be divided into seven genetic clusters. Six clusters comprised and corresponded to the established species B. burgdorferi sensu stricto (n = 23), Borrelia garinii (n = 39), Borrelia afzelii (n = 59), Borrelia japonica (n = 1), Borrelia valaisiana (n = 12), and genomic group DN127 (n = 1). One strain from a patient with erythema migrans (EM) did not belong to any of the species or genomic groups known up to now. The RAPD types of B. burgdorferi sensu stricto, B. garinii, and B. afzelii isolates, which may give rise to human Lyme borreliosis (LB), were associated with their geographic origins. A high degree of genetic diversity was observed among the 39 B. garinii strains, and six subgroups could be recognized. One of these comprised eight isolates from patients with disseminated LB only and no tick isolates. B. afzelii strains from patients with EM or acrodermatitis chronica atrophicans were not clustered in particular branches. Our study showed that RAPD analysis is a powerful tool for discriminating different Borrelia species as well as Borrelia isolates within species. PMID:9508310

  3. Borrelia burgdorferi Sensu Lato Species in Europe Induce Diverse Immune Responses against C6 Peptides in Infected Mice▿

    PubMed Central

    Krupka, Inke; Knauer, Jens; Lorentzen, Leif; O'Connor, Thomas P.; Saucier, Jill; Straubinger, Reinhard K.

    2009-01-01

    The diversity of Lyme-borreliosis-inducing Borrelia species in Europe set high standards for the use of serodiagnostic test systems in terms of specificity and sensitivity. In the United States, the one-step C6 antibody test system based on the invariable domain IR6 of the VlsE molecule has been established as a successful diagnostic tool for testing canine samples. However, only a limited set of data are available regarding the antigenicity of the C6 peptides in an experimental murine model and sensitivity of the test regarding European Borrelia species. In order to investigate antibody reactions induced by these spirochetes, a total of 142 C3H/HeN mice were inoculated with Borrelia burgdorferi sensu stricto N40, B. garinii PBi, two isolates of B. afzelii, B. spielmanii A14S, B. valaisiana Rio6, B. valaisiana VS116, or B. lusitaniae. Infection of the mice was documented utilizing tissue culture and PCR. The IR6 sequences of B. burgdorferi sensu stricto B31, B. garinii IP90, and two B. afzelii ACAI strains have been used to synthesize and test additional C6 peptides. Compared to the well-established two-tiered test system, the results indicate that single C6 peptides derived from B. burgdorferi sensu stricto and B. garinii can be used in an enzyme-linked immunosorbent assay-based technique to detect murine antibodies induced by either agent. Little is known about the prevalence or pathogenicity of the B. afzelii strains in mammalian hosts, but our experimental data indicate differences in the C6 peptide test sensitivity for the detection of antibodies induced by different strains or isolates of B. afzelii. PMID:19726618

  4. Bactericidal Activity of Octenidine to Various Genospecies of Borrelia burgdorferi, Sensu Lato Spirochetes in Vitro and in Vivo.

    PubMed

    Tylewska-Wierzbanowska, Stanisława; Rogulska, Urszula; Lewandowska, Grażyna; Chmielewski, Tomasz

    2017-07-06

    The aim of our studies was to invent a reliable method for detection of the bactericidal activity of disinfectants against Borrelia burgdorferi in suspension (in vitro) and in cell line cultures (in vivo). In the suspension method, 0.01% octenidine at 20°C and 35°C was bactericidal to Borrelia afzeli; Borrelia garini, B. burgdorferi sensu stricto after 5 minutes treatment. Increase of the temperature to 35°C speed up the bactericidal effect to 1 minute. The bactericidal action of octenidine towards B. burgdorferi spirochetes growing in fibroblasts was less effective and needed a longer time to kill them than in the suspension.

  5. Assessment of two new molecular methods for identification of Candida parapsilosis sensu lato species.

    PubMed

    Garcia-Effron, Guillermo; Canton, Emilia; Pemán, Javier; Dilger, Amanda; Romá, Eva; Perlin, David S

    2011-09-01

    Candida parapsilosis sensu stricto, C. orthopsilosis, and C. metapsilosis replaced C. parapsilosis groups I, II, and III in 2005. Since then, an increased interest in studying their epidemiology has arisen based on the observed differences in antifungal susceptibilities and virulence the three species. A strict differentiation of these species cannot be achieved by phenotypic methods. We evaluate two new molecular methodologies to differentiate among these species by the use of a collection of 293 bloodstream infection isolates of C. parapsilosis sensu lato. For the first method, the isolates were studied using PCR amplification of a fragment of the C. parapsilosis sensu lato FKS1 gene and a universal primer pair followed by EcoRI enzyme digestion. The other method used the allele discrimination ability of molecular beacons in a multiplex real-time PCR format. Both methods of identification showed 100% concordance with internal transcribed spacer 1 (ITS1)/ITS2 sequencing and proved to be effective for clinical applications, even with mixed-species DNAs.

  6. Detection of Lyme Disease Bacterium, Borrelia burgdorferi sensu lato, in Blacklegged Ticks Collected in the Grand River Valley, Ontario, Canada.

    PubMed

    Scott, John D; Foley, Janet E; Anderson, John F; Clark, Kerry L; Durden, Lance A

    2017-01-01

    We document the presence of blacklegged ticks, Ixodes scapularis, in the Grand River valley, Centre Wellington, Ontario. Overall, 15 (36%) of 42 I. scapularis adults collected from 41 mammalian hosts (dogs, cats, humans) were positive for the Lyme disease bacterium, Borrelia burgdorferi sensu lato (s.l.). Using real-time PCR testing and DNA sequencing of the flagellin (fla) gene, we determined that Borrelia amplicons extracted from I. scapularis adults belonged to B. burgdorferi sensu stricto (s.s.), which is pathogenic to humans and certain domestic animals. Based on the distribution of I. scapularis adults within the river basin, it appears likely that migratory birds provide an annual influx of I. scapularis immatures during northward spring migration. Health-care providers need to be aware that local residents can present with Lyme disease symptoms anytime during the year.

  7. Detection of Lyme Disease Bacterium, Borrelia burgdorferi sensu lato, in Blacklegged Ticks Collected in the Grand River Valley, Ontario, Canada

    PubMed Central

    Scott, John D.; Foley, Janet E.; Anderson, John F.; Clark, Kerry L.; Durden, Lance A.

    2017-01-01

    We document the presence of blacklegged ticks, Ixodes scapularis, in the Grand River valley, Centre Wellington, Ontario. Overall, 15 (36%) of 42 I. scapularis adults collected from 41 mammalian hosts (dogs, cats, humans) were positive for the Lyme disease bacterium, Borrelia burgdorferi sensu lato (s.l.). Using real-time PCR testing and DNA sequencing of the flagellin (fla) gene, we determined that Borrelia amplicons extracted from I. scapularis adults belonged to B. burgdorferi sensu stricto (s.s.), which is pathogenic to humans and certain domestic animals. Based on the distribution of I. scapularis adults within the river basin, it appears likely that migratory birds provide an annual influx of I. scapularis immatures during northward spring migration. Health-care providers need to be aware that local residents can present with Lyme disease symptoms anytime during the year. PMID:28260991

  8. Molecular Characterization of Echinococcus granulosus Sensu Lato from Farm Animals in Egypt

    PubMed Central

    Amer, Said; Helal, Ibrahim B.; Kamau, Evelyne; Feng, Yaoyu; Xiao, Lihua

    2015-01-01

    Little is known on the diversity and public health significance of Echinococcus species in livestock in Egypt. In this study, 37 individual hydatid cysts were collected from dromedary camels (n=28), sheep (n=7) and buffalos (n=2). DNA was extracted from protoscoleces/germinal layer of individual cysts and amplified by PCR targeting nuclear (actin II) and mitochondrial (COX1 and NAD1) genes. Direct sequencing of amplicons indicated the presence of Echinococcus canadenesis (G6 genotype) in 26 of 28 camel cysts, 3 of 7 sheep cysts and the 2 buffalo derived cysts. In contrast, Echinococcus granulosus sensu stricto (G1 genotype) was detected in one cyst from a camel and 4 of 7 cysts from sheep, whereas Echinococcus ortleppi (G5 genotype) was detected in one cyst from a camel. This is the first identification of E. ortleppi in Egypt. PMID:25760944

  9. Comparative histology of floral elaiophores in the orchids Rudolfiella picta (Schltr.) Hoehne (Maxillariinae sensu lato) and Oncidium ornithorhynchum H.B.K. (Oncidiinae sensu lato)

    PubMed Central

    Davies, Kevin L.; Stpiczyńska, Malgorzata

    2009-01-01

    Background and Aims Floral elaiophores, although widespread amongst orchids, have not previously been described for Maxillariinae sensu lato. Here, two claims that epithelial, floral elaiophores occur in the genus Rudolfiella Hoehne (Bifrenaria clade) are investigated. Presumed elaiophores were compared with those of Oncidiinae Benth. and the floral, resin-secreting tissues of Rhetinantha M.A. Blanco and Heterotaxis Lindl., both genera formerly assigned to Maxillaria Ruiz & Pav. (Maxillariinae sensu stricto). Methods Putative, floral elaiophore tissue of Rudolfiella picta (Schltr.) Hoehne and floral elaiophores of Oncidium ornithorhynchum H.B.K. were examined by means of light microscopy, histochemistry, scanning electron microscopy and transmission electron microscopy. Key Results and Conclusions Floral, epithelial elaiophores are present in Rudolfiella picta, indicating, for the first time, that oil secretion occurs amongst members of the Bifrenaria clade (Maxillariinae sensu lato). However, whereas the elaiophore of R. picta is borne upon the labellar callus, the elaiophores of O. ornithorhynchum occur on the lateral lobes of the labellum. In both species, the elaiophore comprises a single layer of palisade secretory cells and parenchymatous, subsecretory tissue. Cell wall cavities are absent from both and there is no evidence of cuticular distension in response to oil accumulation between the outer tangential wall and the overlying cuticle in R. picta. Distension of the cuticle, however, occurs in O. ornithorhynchum. Secretory cells of R. picta contain characteristic, spherical or oval plastids with abundant plastoglobuli and these more closely resemble plastids found in labellar, secretory cells of representatives of Rhetinantha (formerly Maxillaria acuminata Lindl. alliance) than elaiophore plastids of Oncidiinae. In Rhetinantha, such plastids are involved in the synthesis of resin-like material or wax. Despite these differences, the elaiophore anatomy of

  10. A phylogenetic re-appraisal of the family Liagoraceae sensu lato (Nemaliales, Rhodophyta) based on sequence analyses of two plastid genes and postfertilization development.

    PubMed

    Lin, Showe-Mei; Rodríguez-Prieto, Conxi; Huisman, John M; Guiry, Michael D; Payri, Claude; Nelson, Wendy A; Liu, Shao-Lun

    2015-06-01

    The marine red algal family Liagoraceae sensu lato is shown to be polyphyletic based on analyses of a combined rbcL and psaA data set and the pattern of carposporophyte development. Fifteen of eighteen genera analyzed formed a monophyletic lineage that included the genus Liagora. Nemalion did not cluster with Liagoraceae sensu stricto, and Nemaliaceae is reinstated, characterized morphologically by the formation of the primary gonimolobes by longitudinal divisions of the gonimoblast initial. Yamadaella and Liagoropsis, previously placed in the Dermonemataceae, are shown to be independent lineages and are recognized as two new families Yamadaellaceae and Liagoropsidaceae. Yamadaellaceae is characterized by two gonimoblast initials cut off bilaterally from the fertilized carpogonium and diffusely spreading gonimoblast filaments. Liagoropsidaceae is characterized by at least three gonimoblast initials cut off by longitudinal septa from the fertilized carpogonium. In contrast, Liagoraceae sensu stricto is characterized by a single gonimoblast initial cut off transversely or diagonally from the fertilized carpogonium. Reproductive features, such as diffuse gonimoblasts and unfused carpogonial branches following postfertilization, appear to have evolved on more than one occasion in the Nemaliales and are therefore not taxonomically diagnostic at the family level, although they may be useful in recognizing genera.

  11. Homogeneous Inflammatory Gene Profiles Induced in Human Dermal Fibroblasts in Response to the Three Main Species of Borrelia burgdorferi sensu lato

    PubMed Central

    Meddeb, Mariam; Carpentier, Wassila; Cagnard, Nicolas; Nadaud, Sophie; Grillon, Antoine; Barthel, Cathy; De Martino, Sylvie Josiane; Jaulhac, Benoît; Boulanger, Nathalie

    2016-01-01

    In Lyme borreliosis, the skin is the key site for bacterial inoculation by the infected tick and for cutaneous manifestations. We previously showed that different strains of Borrelia burgdorferi sensu stricto isolated from tick and from different clinical stages of the Lyme borreliosis (erythema migrans, and acrodermatitis chronica atrophicans) elicited a very similar transcriptional response in normal human dermal fibroblasts. In this study, using whole transcriptome microarray chips, we aimed to compare the transcriptional response of normal human dermal fibroblasts stimulated by 3 Borrelia burgdorferi sensu lato strains belonging to 3 main pathogenic species (B. afzelii, B. garinii and B. burgdorferi sensu stricto) in order to determine whether “species-related” inflammatory pathways could be identified. The three Borrelia strains tested exhibited similar transcriptional profiles, and no species-specific fingerprint of transcriptional changes in fibroblasts was observed. Conversely, a common core of chemokines/cytokines (CCL2, CXCL1, CXCL2, CXCL6, CXCL10, IL-6, IL-8) and interferon-related genes was stimulated by all the 3 strains. Dermal fibroblasts appear to play a key role in the cutaneous infection with Borrelia, inducing a homogeneous inflammatory response, whichever Borrelia species was involved. PMID:27706261

  12. Outer Surface Protein C Peptide Derived from Borrelia burgdorferi Sensu Stricto as a Target for Serodiagnosis of Early Lyme Disease

    PubMed Central

    Arnaboldi, Paul M.; Seedarnee, Rudra; Sambir, Mariya; Callister, Steven M.; Imparato, Josephine A.

    2013-01-01

    Current serodiagnostic assays for Lyme disease are inadequate at detecting early infection due to poor sensitivity and nonspecificity that arise from the use of whole bacteria or bacterial proteins as assay targets; both targets contain epitopes that are cross-reactive with epitopes found in antigens of other bacterial species. Tests utilizing peptides that contain individual epitopes highly specific for Borrelia burgdorferi as diagnostic targets are an attractive alternative to current assays. Using an overlapping peptide library, we mapped linear epitopes in OspC, a critical virulence factor of B. burgdorferi required for mammalian infection, and confirmed the results by enzyme-linked immunosorbent assay (ELISA). We identified a highly conserved 20-amino-acid peptide epitope, OspC1. Via ELISA, OspC1 detected specific IgM and/or IgG in 60 of 98 serum samples (62.1%) obtained from patients with erythema migrans (early Lyme disease) at the time of their initial presentation. By comparison, the commercially available OspC peptide PepC10 detected antibody in only 48 of 98 serum samples (49.0%). In addition, OspC1 generated fewer false-positive results among negative healthy and diseased (rheumatoid arthritis and positive Rapid Plasma Reagin [RPR+] test result) control populations than did PepC10. Both highly specific and more sensitive than currently available OspC peptides, OspC1 could have value as a component of a multipeptide Lyme disease serological assay with significantly improved capabilities for the diagnosis of early infection. PMID:23365204

  13. Ecological strategies of Al-accumulating and non-accumulating functional groups from the cerrado sensu stricto.

    PubMed

    Souza, Marcelo C de; Bueno, Paula C P; Morellato, Leonor P C; Habermann, Gustavo

    2015-01-01

    The cerrado's flora comprises aluminum-(Al) accumulating and non-accumulating plants, which coexist on acidic and Al-rich soils with low fertility. Despite their existence, the ecological importance or biological strategies of these functional groups have been little explored. We evaluated the leaf flushing patterns of both groups throughout a year; leaf concentrations of N, P, K, Ca, Mg, S, Al, total flavonoids and polyphenols; as well as the specific leaf area (SLA) on young and mature leaves within and between the groups. In Al-accumulating plants, leaf flushed throughout the year, mainly in May and September; for non-accumulating plants, leaf flushing peaked at the dry-wet seasons transition. However, these behaviors could not be associated with strategies for building up concentrations of defense compounds in leaves of any functional groups. Al-accumulating plants showed low leaf nutrient concentrations, while non-accumulating plants accumulated more macronutrients and produced leaves with high SLA since the juvenile leaf phase. This demonstrates that the increase in SLA is slower in Al-accumulating plants that are likely to achieve SLA values comparable to the rest of the plant community only in the wet season, when sunlight capture is important for the growth of new branches.

  14. Genetic diversity, endemism and phylogeny of lampreys within the genus Lampetra sensu stricto (Petromyzontiformes: Petromyzontidae) in western North America.

    PubMed

    Boguski, D A; Reid, S B; Goodman, D H; Docker, M F

    2012-11-01

    Phylogenetic structure of four Lampetra species from the Pacific drainage of North America (western brook lamprey Lampetra richardsoni, Pacific brook lamprey Lampetra pacifica, river lamprey Lampetra ayresii and Kern brook lamprey Lampetra hubbsi) and unidentified Lampetra specimens (referred to as Lampetra sp.) from 36 locations was estimated using the mitochondrial cytochrome b gene. Maximum parsimony and Bayesian inferences did not correspond with any taxonomic scheme proposed to date. Rather, although L. richardsoni (from Alaska to California) and L. ayresii (from British Columbia to California) together constituted a well-supported clade distinct from several genetically divergent Lampetra populations in Oregon and California, these two species were not reciprocally monophyletic. The genetically divergent populations included L. pacifica (from the Columbia River basin) and L. hubbsi (from the Kern River basin) and four Lampetra sp. populations in Oregon (Siuslaw River and Fourmile Creek) and California (Kelsey and Mark West Creeks). These four Lampetra sp. populations showed genetic divergence between 2.3 and 5.7% from any known species (and up to 8.0% from each other), and may represent morphologically cryptic and thus previously undescribed species. A fifth population (from Paynes Creek, California) may represent a range extension of L. hubbsi into the Upper Sacramento River. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

  15. A HIGHLY SELECTIVE PCR PROTOCOL FOR DETECTING 16S RRNA GENES OF THE GENUS PSEUDOMONAS (SENSU STRICTO) IN ENVIRONMENTAL SAMPLES

    EPA Science Inventory

    Pseudomonas species are plant, animal, and human pathogens; exhibit plant pathogen-suppressing properties useful in biological control; or express metabolic versatilities valued in biotechnology and bioremediation. Specific detection of Pseudomonas species in the environment may ...

  16. MULTIPLE ENZYME RESTRICTION FRAGMENT LENGTH POLYMORPHISM ANALYSIS FOR HIGH RESOLUTION DISTINCTION OF PSEUDOMONAS (SENSU STRICTO) 16S RRNA GENES

    EPA Science Inventory

    Pseudomonas specific 16S rDNA PCR amplification and multiple enzyme restriction fragment length polymorphism (MERFLP) analysis using a single digestion mixture of Alu I, Hinf I, Rsa I, and Tru 9I distinguished 150 published sequences and reference strains of authentic Pseudomonas...

  17. MULTIPLE ENZYME RESTRICTION FRAGMENT LENGTH POLYMORPHISM ANALYSIS FOR HIGH RESOLUTION DISTINCTION OF PSEUDOMONAS (SENSU STRICTO) 16S RRNA GENES

    EPA Science Inventory

    Pseudomonas specific 16S rDNA PCR amplification and multiple enzyme restriction fragment length polymorphism (MERFLP) analysis using a single digestion mixture of Alu I, Hinf I, Rsa I, and Tru 9I distinguished 150 published sequences and reference strains of authentic Pseudomonas...

  18. A HIGHLY SELECTIVE PCR PROTOCOL FOR DETECTING 16S RRNA GENES OF THE GENUS PSEUDOMONAS (SENSU STRICTO) IN ENVIRONMENTAL SAMPLES

    EPA Science Inventory

    Pseudomonas species are plant, animal, and human pathogens; exhibit plant pathogen-suppressing properties useful in biological control; or express metabolic versatilities valued in biotechnology and bioremediation. Specific detection of Pseudomonas species in the environment may ...

  19. Occurrence of Anisakis simplex sensu stricto in imported Atlantic mackerel (Scomber scombrus) represents a risk for Turkish consumers.

    PubMed

    Pekmezci, Gokmen Zafer

    2014-08-18

    Anisakid larvae are a prevalent food-borne pathogen that has been found in numerous fish species destined for human consumption. The accidental consumption of infected raw or poorly cooked fish may cause gastroenteric diseases and allergies in humans. In spite of the fact that thorough cooking or freezing kills Anisakis worms, this method does not destroy their allergenic capacity. The presence of A. simplex (s.s.) in seafood products may present a health risk for consumers. In Turkey, Atlantic mackerels are marketed as frozen and mainly imported from Norway. The aim of this study was to identify the Anisakis species found in deep-frozen whole Atlantic mackerel (Scomber scombrus) destined for human consumption in fish markets that imported fish from Norway to Turkey. All Anisakis larvae isolated from imported Atlantic mackerel were identified via morphology as third larvae of Anisakis Type I. The ITS region (ITS-1, 5.8S subunit, ITS-2) was amplified and digested with the restriction enzymes Hinf I and Hha I. Larvae of the genus Anisakis were identified via PCR-RFLP as belonging to Anisakis simplex (s.s.), and this was confirmed by sequencing the cox2 gene. The overall prevalence of Anisakis larvae was 25% (95% confidence limits: 13-41%), and the mean intensity was 19.1 (bootstrap 95% confidence limits: 15.3-25.5). Recognized zoonotic A. simplex (s.s.) larvae found in imported Atlantic mackerel could represent a risk. Those who consume them could acquire parasitic allergies. The results will have an important impact on public health risk assessment in that they suggest reviewing critical control points at the Hazard Analysis Critical Control Point (HACCP) programmer to reduce the risk of anisakid-induced allergies among consumers. Consequently, the present study provides the first data regarding the occurrence of A. simplex (s.s.) larvae in imported Atlantic mackerel in Turkish markets.

  20. Essential drugs in the Gambia.

    PubMed

    Jallow, M T

    1993-01-01

    The Gambia is a small West African country with a population of approximately 900,000. With more than half of the 48 physicians registered in 1989 in the public sector working in the country's main hospital, nurses are responsible for most drug prescribing in the public health care system. At the primary care level, village health workers, most of whom are illiterate, are trained to prescribe a limited number of drugs. Numerous difficulties in this field prompted the Gambia to request assistance from the World Health Organization's Drug Action Program in reviewing the pharmaceutical sector and formulating a national drug policy. The Essential Drugs Program was introduced in 1984 with the main objectives of achieving regulatory control over drugs in the private sector and the availability of safe, effective, and affordable drugs in the public sector. Assessment of the impact and progress of the program indicate that the essential drugs concept in the country has helped resolve some serious problems. The Essential Drugs Program has substantially improved the efficacy and efficiency of pharmaceutical services in the Gambia. While the small size of the country can be an asset when implementing national programs, only very limited scope exists for training medical and other health workers. The national drug policy, the essential drugs list, the state supply system, the private sector, and the drug revolving funds project are discussed.

  1. A novel multilocus phylogenetic estimation reveals unrecognized diversity in Asian horned toads, genus Megophrys sensu lato (Anura: Megophryidae).

    PubMed

    Chen, Jin-Min; Zhou, Wei-Wei; Poyarkov, Nikolay A; Stuart, Bryan L; Brown, Rafe M; Lathrop, Amy; Wang, Ying-Yong; Yuan, Zhi-Yong; Jiang, Ke; Hou, Mian; Chen, Hong-Man; Suwannapoom, Chatmongkon; Nguyen, Sang Ngoc; Duong, Tang Van; Papenfuss, Theodore J; Murphy, Robert W; Zhang, Ya-Ping; Che, Jing

    2017-01-01

    The horned toad assemblage, genus Megophrys sensu lato, currently includes three groups previously recognized as the genera Atympanophrys, Xenophrys and Megophrys sensu stricto. The taxonomic status and species composition of the three groups remain controversial due to conflicting phenotypic analyses and insufficient phylogenetic reconstruction; likewise, the position of the monotypic Borneophrys remains uncertain with respect to the horned toads. Further, the diversity of the horned toads remains poorly understood, especially for widespread species. Herein, we evaluate species-level diversity based on 45 of the 57 described species from throughout southern China, Southeast Asia and the Himalayas using Bayesian inference trees and the Generalized Mixed Yule Coalescent (GMYC) approach. We estimate the phylogeny using both mitochondrial and nuclear DNA data. Analyses reveal statistically significant mito-nuclear discordance. All analyses resolve paraphyly for horned toads involving multiple strongly supported clades. These clades correspond with geography. We resurrect the genera Atympanophrys and Xenophrys from the synonymy of Megophrys to eliminate paraphyly of Megophrys s.l. and to account for the morphological, molecular and biogeographic differences among these groups, but we also provide an alternative option. Our study suggests that Borneophrys is junior synonym of Megophrys sensu stricto. We provide an estimation of timeframe for the horned toads. The mitochondrial and nuclear trees indicate the presence of many putative undescribed species. Widespread species, such as Xenophrys major and X. minor, likely have dramatically underestimated diversity. The integration of morphological and molecular evidence can validate this discovery. Montane forest dynamics appear to play a significant role in driving diversification of horned toads.

  2. Laboratory evaluation of three commercial coil products for protection efficacy against Anopheles gambiae from southern Ghana: a preliminary study.

    PubMed

    Avicor, S W; Wajidi M, F F; Jaal, Z

    2015-06-01

    Residents in irrigated urban agricultural sites face numerous mosquito problems such as increased mosquito populations and reduced insecticides susceptibility due to the creation of mosquito breeding sites and agricultural use of insecticides and hence require effective protective products against them. In this study, the protection effectiveness of three pyrethroid formulated mosquito coils of Malaysian origin against Anopheles gambiae sensu lato from an irrigated urban agricultural site in Ghana were evaluated for their potential use. Sucrose fed An. gambiae s.l. were exposed to insecticide-containing coils in a 70 cm x 70 cm x 70 cm glass chamber to assess the insecticidal effect of the coils. The 0.005% metofluthrin coil caused the most rapid knockdown of 50% of the test mosquitoes. The mean lethal effect of the coils on An. gambiae s.l. were as follows; 0.005% metofluthrin (86%), 0.3% d-allethrin (74.33%), 0.15% d-trans allethrin (72%) and the 0.25% d-allethrin reference coil (69%). The 0.005% metofluthrin coil achieved the highest insecticidal effect on An. gambiae s.l. compared to the other coils and hence performed better than the others as an anti-mosquito product. All the three test coils were effective against An. gambaie s.l. from the irrigated agricultural site compared to the reference coil.

  3. Why are there several species of Borrelia burgdorferi sensu lato detected in dogs and humans?

    PubMed

    Skotarczak, Bogumiła

    2014-04-01

    Borrelia burgdorferi sensu lato is a group of spirochete bacteria species some of which cause borreliosis in humans and dogs. Humans and dogs are susceptible to illness from many of the same tick-borne pathogens, including B. burgdorferi s.l. (Bbsl). Little is known about the pathogenic role of the species of Bbsl in canines. The molecular methods which detect and amplify the DNA of borreliae and allow differentiating borreliae species or strains have not been used in canine diagnostics yet. Until now, it has been believed that in European dogs, like in humans, at least three pathogenic species occur but the most frequently described symptoms may be associated with the infection caused by B. burgdorferi sensu stricto species. A dog as well as a human is a host for many species of Bbsl, because borreliacidal ability of serum of dogs and humans is evident only in certain genospecies of Bbsl. Therefore both a dog and a human harbor more species than in case of some wild animal species which create older phylogenetic Bbsl species-host systems and these animals may act even as a non-competent reservoir host. Apart from many genospecies of Bbsl, a dog harbors other tick-borne agents and dual or triple infections may occur.

  4. Prevalence of Borrelia burgdorferi sensu lato in Ixodes ricinus ticks collected from southern Poland.

    PubMed

    Strzelczyk, Joanna K; Gaździcka, Jadwiga; Cuber, Piotr; Asman, Marek; Trapp, Gizela; Gołąbek, Karolina; Zalewska-Ziob, Marzena; Nowak-Chmura, Magdalena; Siuda, Krzysztof; Wiczkowski, Andrzej; Solarz, Krzysztof

    2015-12-01

    In 2008-2011 ticks were collected from southern Poland. Out of 6336 individuals collected and identified as Ixodes ricinus, 768 (2 larvae, 84 nymphs, 417 females, 265 males) were included in molecular study. The aim of this study was to investigate the prevalence and types of genospecies of Borrelia burgdorferi sensu lato in ticks. The polymerase chain reaction (PCR) was applied to detect the presence of pathogens in ticks. Subsequently the amplified DNA was digested with TasI enzyme. The infection rate was 15% (116) of examined ticks. PCR-RFLP analysis allowed distinguishing three genospecies of B. burgdorferi s.l.: B. burgdorferi sensu stricto, B. afzelii, and B. garinii. RFLP analyses of 116 positive samples revealed 96 (83%) monoinfections and 13 (11%) coinfections, whereas unidentified genospecies were present in 7 (6%) of positive samples. In the case of monoinfections, B. burgdorferi s.s. was the predominant species of pathogen in infected ticks - 61.4%. Other genospecies: B. garinii and B. afzelii were detected in 22.9% and 15.6% of the samples, respectively. To sum up, 15 % of ticks were infected by B. burgdorferi s.l which increases the risk of human infections in the recreational areas of southern Poland. Furthermore, there is a need to increase public awareness and implement more preventive measures concerning Lyme disease.

  5. Delineation of a new species of the Borrelia burgdorferi Sensu Lato Complex, Borrelia americana sp. nov.

    PubMed

    Rudenko, Nataliia; Golovchenko, Maryna; Lin, Tao; Gao, Lihui; Grubhoffer, Libor; Oliver, James H

    2009-12-01

    Analysis of borrelia isolates collected from ticks, birds, and rodents from the southeastern United States revealed the presence of well-established populations of Borrelia burgdorferi sensu stricto, Borrelia bissettii, Borrelia carolinensis, and Borrelia sp. nov. Multilocus sequence analysis of five genomic loci from seven samples representing Borrelia sp. nov. isolated from nymphal Ixodes minor collected in South Carolina showed their close relatedness to California strains known as genomospecies 1 and separation from any other known species of the B. burgdorferi sensu lato complex. One nucleotide difference in the size of the 5S-23S intergenic spacer region, one substitution in 16S rRNA gene signature nucleotides, and silent nucleotide substitutions in sequences of the gene encoding flagellin and the gene p66 clearly separate Borrelia sp. nov. isolates from South Carolina into two subgroups. The sequences of isolates of each subgroup share the same restriction fragment length polymorphism patterns of the 5S-23S intergenic spacer region and contain unique signature nucleotides in the 16S rRNA gene. We propose that seven Borrelia sp. nov. isolates from South Carolina and two California isolates designated as genomospecies 1 comprise a single species, which we name Borrelia americana sp. nov. The currently recognized geographic distribution of B. americana is South Carolina and California. All strains are associated with Ixodes pacificus or Ixodes minor and their rodent and bird hosts.

  6. A molecular phylogeny and classification of Leptochloa (Poaceae: Chloridoideae: Chlorideae) sensu lato and related genera

    PubMed Central

    Peterson, Paul M.; Romaschenko, Konstantin; Snow, Neil; Johnson, Gabriel

    2012-01-01

    Background and Aims Leptochloa (including Diplachne) sensu lato (s.l.) comprises a diverse assemblage of C4 (NAD-ME and PCK) grasses with approx. 32 annual or perennial species. Evolutionary relationships and a modern classification of Leptochloa spp. based on the study of molecular characters have only been superficially investigated in four species. The goals of this study were to reconstruct the evolutionary history of Leptochloa s.l. with molecular data and broad taxon sampling. Methods A phylogenetic analysis was conducted of 130 species (mostly Chloridoideae), of which 22 are placed in Leptochloa, using five plastid (rpL32-trn-L, ndhA intron, rps16 intron, rps16-trnK and ccsA) and the nuclear ITS 1 and 2 (ribosomal internal transcribed spacer regions) to infer evolutionary relationships and revise the classification. Key results Leptochloa s.l. is polyphyletic and strong support was found for five lineages. Embedded within the Leptochloa sensu stricto (s.s.) clade are two Trichloris spp. and embedded in Dinebra are Drake-brockmania and 19 Leptochloa spp. Conclusions The molecular results support the dissolution of Leptochloa s.l. into the following five genera: Dinebra with 23 species, Diplachne with two species, Disakisperma with three species, Leptochloa s.s. with five species and a new genus, Trigonochloa, with two species. PMID:22628365

  7. Molecular systematics in the acanthocephalan genus Echinorhynchus (sensu lato) in northern Europe.

    PubMed

    Väinölä, R; Valtonen, E T; Gibson, D I

    1994-01-01

    New biological species and high levels of inter- and intraspecific genetic divergence were discovered in an allozyme study of some North European members of the acanthocephalan genus Echinorhynchus (sensu lato), parasites of fish and malacostracan crustaceans. (i) A strong differentiation between the marine E. gadi and the fresh- and brackish-water E. salmonis (genetic identity I congruent to 0) supports a generic distinction between these taxa; however, the subdivision would not entirely concur with the concepts of Echinorhynchus (sensu stricto) and Metechinorhynchus suggested earlier. (ii) Samples of E. gadi from the Baltic, Norwegian and North Seas included three distinct, partially sympatric biological species (spp. I-III; I congruent to 0.5). (iii) E. bothniensis, previously only known from the northern Baltic Sea, represents a complex of freshwater taxa with an intermediate host relationship to the 'glacial relict' Mysis spp. and with a distributional and host analogy to the North American E. leidyi. A population in a northern lake in the Barents Sea basin is closely related to E. bothniensis of the Baltic area, but is probably specifically distinct; the divergence between these populations (I congruent to 0.6) is similar to that between their Mysis host species. (iv) Considerable intraspecific differentiation (FST = 0.25), probably reflecting post-glacial population bottlenecks, was found between Baltic and nearby lacustrine E. bothniensis, and between Atlantic and Baltic E. gadi sp. I.

  8. Borrelia burgdorferi sensu lato diversity and its influence on pathogenicity in humans.

    PubMed

    Baranton, Guy; De Martino, Sylvie J

    2009-01-01

    Among the Spirochaetes, the Borrelia burgdorferi sensu lato complex is responsible for Lyme borreliosis. This complex comprises more than 13 Borrelia species. Four of them are clearly pathogenic for humans: B. burgdorferi sensu stricto, B. afzelii, B. garinii and B. spielmanii. They can generate erythema migrans, an initial skin lesion, and can then spread deeply into the host to invade distant tissues, especially the nervous system, the joints or the skin. In humans, Borrelia pathogenicityseems to be linked with taxonomic position, but in vitro studies show the role of plasmids in B. burgdorferi s.l. pathogenesis. The inter- and intraspecies genetic diversity of B. burgdorferi s.l. evidences a clonal evolution of the chromosome, while plasmid genes are quite variable, suggesting their major role in Borrelia adaptability. The plasmid-encoded adhesins and vlse, crasps and osp genes determine invasiveness and host immune evasion of B. burgdorferi s.l., and select the bacterial host spectrum. The geographic distribution of B. burgdorferi s.l. is closely related to its vectors and competent hosts, and its development within these influences its diversity, taxonomy and pathogenesis, primarily via genetic lateral transfer. Copyright 2009 S. Karger AG, Basel.

  9. Calosoma aethiops (Jeannel, 1940) as a new synonym of Calosoma imbricatum hottentotum Chaudoir, 1852, a new status of Calosoma roeschkei Breuning, 1927, and a revision of the Calosoma senegalense group sensu Häckel, 2012 (Coleoptera, Carabidae, Carabini)

    PubMed Central

    Häckel, Martin; Farkač, Jan; Sehnal, Rostislav

    2016-01-01

    Abstract Calosoma aethiops (Jeannel, 1940) as a new synonym of Calosoma imbricatum hottentotum Chaudoir, 1852, a new status of Calosoma roeschkei Breuning, 1927, and a revision of the Calosoma senegalense group sensu Häckel, 2012 (Coleoptera: Carabidae: Carabini). Conducted is a taxonomic revision of the Calosoma senegalense group sensu Häckel, 2012. Placed in the group sensu stricto are four species: Calosoma planicolle Chaudoir, 1869, Calosoma scabrosum Chaudoir, 1843, Calosoma senegalense Dejean, 1831, and Ctenosta strandi Breuning, 1934. Calosoma aethiops Jeannel, 1940 is synonymized with Calosoma imbricatum hottentotum Chaudoir, 1852, and Calosoma roeschkei Breuning, 1927 is newly regarded as a subspecies of Calosoma scabrosum. The taxonomic conclusions are based on morphometry of the holotypes and 10 male and 10 female specimens of each taxon, and on morphology of the aedeagus including inflated endophalus. PMID:27563269

  10. Real-time PCR-based identification of Borrelia burgdorferi sensu lato species in ticks collected from humans in Romania.

    PubMed

    Briciu, Violeta T; Meyer, Fabian; Sebah, Daniela; Tăţulescu, Doina F; Coroiu, Georgiana; Lupşe, Mihaela; Carstina, Dumitru; Mihalca, Andrei D; Hizo-Teufel, Cecilia; Klier, Christiane; Huber, Ingrid; Fingerle, Volker

    2014-09-01

    The aims of our study were to determine (i) which tick species bite humans in Romania and (ii) the prevalence of Borrelia (B.) burgdorferi genospecies in these ticks. All ticks collected from patients who presented to the Clinic of Infectious Diseases Cluj Napoca in spring/summer 2010 were morphologically identified by an entomologist and tested for B. burgdorferi genospecies prevalence by a real-time PCR assay targeting the hbb gene and melting curve analysis. Out of 532 ticks, 518 were Ixodes ricinus, 10 Dermacentor marginatus, and 3 Haemaphysalis spp. ticks, and one unidentified tick due to destruction. Since evaluation of the hbb PCR revealed that it was not possible to differentiate between B. spielmanii/B. valaisiana and B. garinii/B. bavariensis, sequencing of an 800-bp fragment of the ospA gene was performed in these cases. Out of 389 investigated ticks, 43 were positive by hbb PCR for B. burgdorferi sensu lato. The positive samples were 42 Ixodes ricinus (11.1% B. burgdorferi sensu lato prevalence) and the one unidentified tick. Species identification revealed the presence of mainly B. afzelii, but also of B. garinii, B. burgdorferi sensu stricto, B. valaisiana, and B. lusitaniae. In 4 samples, differentiation between B. spielmanii/B. valaisiana was impossible. Our study shows that the most relevant human pathogenic B. burgdorferi genospecies - predominantly B. afzelii - are present in ticks collected from Romanian patients.

  11. Isolation of live Borrelia burgdorferi sensu lato spirochaetes from patients with undefined disorders and symptoms not typical for Lyme borreliosis.

    PubMed

    Rudenko, N; Golovchenko, M; Vancova, M; Clark, K; Grubhoffer, L; Oliver, J H

    2016-03-01

    Lyme borreliosis is a multisystem disorder with a diverse spectrum of clinical manifestations, caused by spirochaetes of the Borrelia burgdorferi sensu lato complex. It is an infectious disease that can be successfully cured by antibiotic therapy in the early stages; however, the possibility of the appearance of persistent signs and symptoms of disease following antibiotic treatment is recognized. It is known that Lyme borreliosis mimics multiple diseases that were never proven to have a spirochaete aetiology. Using complete modified Kelly-Pettenkofer medium we succeeded in cultivating live B. burgdorferi sensu lato spirochaetes from samples taken from people who suffered from undefined disorders, had symptoms not typical for Lyme borreliosis, but who had undergone antibiotic treatment due to a suspicion of having Lyme disease even though they were seronegative. We report the first recovery of live B. burgdorferi sensu stricto from residents of southeastern USA and the first successful cultivation of live Borrelia bissettii-like strain from residents of North America. Our results support the fact that B. bissettii is responsible for human Lyme borreliosis worldwide along with B. burgdorferi s.s. The involvement of new spirochaete species in Lyme borreliosis changes the understanding and recognition of clinical manifestations of this disease.

  12. Echinococcus granulosus sensu lato genotypes infecting humans--review of current knowledge.

    PubMed

    Alvarez Rojas, Cristian A; Romig, Thomas; Lightowlers, Marshall W

    2014-01-01

    Genetic variability in the species group Echinococcus granulosus sensu lato is well recognised as affecting intermediate host susceptibility and other biological features of the parasites. Molecular methods have allowed discrimination of different genotypes (G1-10 and the 'lion strain'), some of which are now considered separate species. An accumulation of genotypic analyses undertaken on parasite isolates from human cases of cystic echinococcosis provides the basis upon which an assessment is made here of the relative contribution of the different genotypes to human disease. The allocation of samples to G-numbers becomes increasingly difficult, because much more variability than previously recognised exists in the genotypic clusters G1-3 (=E. granulosus sensu stricto) and G6-10 (Echinococcus canadensis). To accommodate the heterogeneous criteria used for genotyping in the literature, we restrict ourselves to differentiate between E. granulosus sensu stricto (G1-3), Echinococcus equinus (G4), Echinococcus ortleppi (G5) and E. canadensis (G6-7, G8, G10). The genotype G1 is responsible for the great majority of human cystic echinococcosis worldwide (88.44%), has the most cosmopolitan distribution and is often associated with transmission via sheep as intermediate hosts. The closely related genotypes G6 and G7 cause a significant number of human infections (11.07%). The genotype G6 was found to be responsible for 7.34% of infections worldwide. This strain is known from Africa and Asia, where it is transmitted mainly by camels (and goats), and South America, where it appears to be mainly transmitted by goats. The G7 genotype has been responsible for 3.73% of human cases of cystic echinococcosis in eastern European countries, where the parasite is transmitted by pigs. Some of the samples (11) could not be identified with a single specific genotype belonging to E. canadensis (G6/10). Rare cases of human cystic echinococcosis have been identified as having been caused by

  13. Neuropeptides and Peptide Hormones in Anopheles gambiae

    NASA Astrophysics Data System (ADS)

    Riehle, Michael A.; Garczynski, Stephen F.; Crim, Joe W.; Hill, Catherine A.; Brown, Mark R.

    2002-10-01

    The African malaria mosquito, Anopheles gambiae, is specialized for rapid completion of development and reproduction. A vertebrate blood meal is required for egg production, and multiple feedings subsequently allow transmission of malaria parasites, Plasmodium spp. Regulatory peptides from 35 genes annotated from the A. gambiae genome likely coordinate these and other physiological processes. Plasmodium parasites may affect actions of newly identified insulin-like peptides, which coordinate growth and reproduction of its vector, A. gambiae, as in Drosophila melanogaster, Caenorhabditis elegans, and mammals. This genomic information provides a basis to expand understanding of hematophagy and pathogen transmission in this mosquito.

  14. Health visiting in rural Gambia.

    PubMed

    Hoare, K

    1991-01-01

    A British nurse was the 1st health visitor in the village of Keneba in the Gambia. She was at a nutritional research center which provided basic medical services. In addition to visiting mothers in their homes to talk about health education, such as oral rehydration and advice on hand washing, she would also encourage them to bring their children to the infant welfare clinic for immunizations. She told the mothers that the health staff would check the growth and nutritional status of their children and why these activities were important. Staff at the clinic aimed to see all the children 2 years 9 times the 1st year and 4 times the 2nd year. All anthropometric data were forwarded to Cambridge, England to be included in a continuing study on the growth of the population. The clinic referred children with serious illnesses to the pediatrician or, if necessary, took them to a hospital on the coast. Children that came to the clinic with a fever 37.4 degrees Celsius during the wet season had a blood film taken to check for malaria parasites. Indeed cerebral malaria contributed greatly to child deaths in the Gambia. If malaria was present, children received their 1st dose of chloroquine immediately so the staff could determine tolerance. 3 doses followed this dose. The health visitor also organized the health education component of the clinic. The clinic dresser interpreted the British nurse's presentations to eventually conduct them alone. The nurse divided the mothers and fathers into 2 groups. In the future, she would evaluate the 2 groups to determine if weekly education on hand washing and skin hygiene would reduce diarrheal and cutaneous disease incidence in children 3 years old. The other group learned about family planning. Both groups learned about immunization, detection of illness, safety, sanitation, nutritional advice, dental care, and food preparation.

  15. Anopheles gambiae complex along The Gambia river, with particular reference to the molecular forms of An. gambiae s.s

    PubMed Central

    Caputo, Beniamino; Nwakanma, Davis; Jawara, Musa; Adiamoh, Majidah; Dia, Ibrahima; Konate, Lassana; Petrarca, Vincenzo; Conway, David J; della Torre, Alessandra

    2008-01-01

    Background The geographic and temporal distribution of M and S molecular forms of the major Afrotropical malaria vector species Anopheles gambiae s.s. at the western extreme of their range of distribution has never been investigated in detail. Materials and methods Collections of indoor-resting An. gambiae s.l. females were carried out along a ca. 400 km west to east transect following the River Gambia from the western coastal region of The Gambia to south-eastern Senegal during 2005 end of rainy season/early dry season and the 2006 rainy season. Specimens were identified to species and molecular forms by PCR-RFLP and the origin of blood-meal of fed females was determined by ELISA test. Results Over 4,000 An. gambiae s.l. adult females were collected and identified, 1,041 and 3,038 in 2005 and 2006, respectively. M-form was mainly found in sympatry with Anopheles melas and S-form in the western part of the transect, and with Anopheles arabiensis in the central part. S-form was found to prevail in rural Sudan-Guinean savannah areas of Eastern Senegal, in sympatry with An. arabiensis. Anopheles melas and An. arabiensis relative frequencies were generally lower in the rainy season samples, when An. gambiae s.s. was prevailing. No large seasonal fluctuations were observed for M and S-forms. In areas where both M and S were recorded, the frequency of hybrids between them ranged from to 0.6% to 7%. Discussion The observed pattern of taxa distribution supports the hypothesis of a better adaptation of M-form to areas characterized by water-retaining alluvial deposits along the Gambia River, characterized by marshy vegetation, mangrove woods and rice cultivations. In contrast, the S-form seems to be better adapted to free-draining soil, covered with open woodland savannah or farmland, rich in temporary larval breeding sites characterizing mainly the eastern part of the transect, where the environmental impact of the Gambia River is much less profound and agricultural

  16. The Phylogeny of Bacillus cereus sensu lato.

    PubMed

    Okinaka, Richard T; Keim, Paul

    2016-02-01

    The three main species of the Bacillus cereus sensu lato, B. cereus, B. thuringiensis, and B. anthracis, were recognized and established by the early 1900 s because they each exhibited distinct phenotypic traits. B. thuringiensis isolates and their parasporal crystal proteins have long been established as a natural pesticide and insect pathogen. B. anthracis, the etiological agent for anthrax, was used by Robert Koch in the 19th century as a model to develop the germ theory of disease, and B. cereus, a common soil organism, is also an occasional opportunistic pathogen of humans. In addition to these three historical species designations, are three less-recognized and -understood species: B. mycoides, B. weihenstephanensis, and B. pseudomycoides. All of these "species" combined comprise the Bacillus cereus sensu lato group. Despite these apparently clear phenotypic definitions, early molecular approaches to separate the first three by various DNA hybridization and 16S/23S ribosomal sequence analyses led to some "confusion" because there were limited differences to differentiate between these species. These and other results have led to frequent suggestions that a taxonomic change was warranted to reclassify this group to a single species. But the pathogenic properties of B. anthracis and the biopesticide applications of B. thuringiensis appear to "have outweighed pure taxonomic considerations" and the separate species categories are still being maintained. B. cereus sensu lato represents a classic example of a now common bacterial species taxonomic quandary.

  17. Implementation of new tools in molecular epidemiology studies of Echinococcus granulosus sensu lato in South America.

    PubMed

    Avila, Héctor G; Santos, Guilherme B; Cucher, Marcela A; Macchiaroli, Natalia; Pérez, Matías G; Baldi, Germán; Jensen, Oscar; Pérez, Verónica; López, Raúl; Negro, Perla; Scialfa, Exequiel; Zaha, Arnaldo; Ferreira, Henrique B; Rosenzvit, Mara; Kamenetzky, Laura

    2017-06-01

    The aim of this work was to determine Echinococcus granulosus sensu lato species and genotypes in intermediate and definitive hosts and in human isolates from endemic regions of Argentina and Brazil including those where no molecular data is available by a combination of classical and alternative molecular tools. A total of 227 samples were isolated from humans, natural intermediate and definitive hosts. Amplification of cytochrome c oxidase subunit I gene fragment was performed and a combination of AluI digestion assay, High Resolution Melting analysis (HRM) assay and DNA sequencing was implemented for Echinococcus species/genotype determination. E. granulosus sensu stricto (G1) was found in sheep (n=35), cattle (n=67) and dogs (n=5); E. ortleppi (G5) in humans (n=3) and cattle (n=108); E. canadensis (G6) in humans (n=2) and E. canadensis (G7) in pigs (n=7). We reported for the first time the presence of E. ortleppi (G5) and E. canadensis (G6) in humans from San Juan and Catamarca Argentinean provinces and E. canadensis (G7) in pigs from Cordoba Argentinean province. In this work, we widened molecular epidemiology studies of E. granulosus s. l. in South America by analyzing several isolates from definitive and intermediate hosts, including humans from endemic regions were such information was scarce or unavailable. The presence of different species/genotypes in the same region and host species reinforce the need of rapid and specific techniques for accurate determination of Echinococcus species such as the ones proposed in this work.

  18. Genetic characterization of Rhipicephalus sanguineus (sensu lato) ticks from dogs in Portugal.

    PubMed

    Dantas-Torres, Filipe; Maia, Carla; Latrofa, Maria Stefania; Annoscia, Giada; Cardoso, Luís; Otranto, Domenico

    2017-03-13

    The taxonomic status of the brown dog tick Rhipicephalus sanguineus (sensu stricto) is a subject of on-going debate; there is a consensus that populations of this tick species should be referred to as R. sanguineus (sensu lato) until its taxonomic status is resolved. Recent genetic studies revealed the existence of more than one lineage of R. sanguineus (s.l.) in temperate countries. In this study, we assessed the genetic identity of ticks collected from rural dogs living in several areas located in all major geographical regions of Portugal. A total of 347 ticks were collected from rural dogs living in different regions of Portugal. These ticks were morphologically identified and partial mitochondrial 16S rRNA gene sequences (~300 bp) were obtained from representative specimens. The ticks were morphologically identified as Ixodes ricinus (seven males and 27 females), Rhipicephalus bursa (one male), Rhipicephalus pusillus (one female) and R. sanguineus (s.l.) (two larvae, 101 nymphs, 108 males and 100 females). Partial mitochondrial 16S rRNA gene sequences were obtained from 58 R. sanguineus (s.l.) specimens, and all of them were genetically identified as belonging to the so-called temperate lineage of R. sanguineus (s.l.) CONCLUSIONS: These results strongly suggest that the temperate species of R. sanguineus (s.l.) is the only representative of this tick group found on dogs in Portugal. It also adds weight to the hypothesis that Rhipicephalus turanicus is not present in this country, although further investigations are necessary to confirm this.

  19. Borrelia burgdorferi sensu lato in Ixodes longiscutatus ticks from Brazilian Pampa.

    PubMed

    Dall'Agnol, Bruno; Michel, Thaís; Weck, Bárbara; Souza, Ugo Araújo; Webster, Anelise; Leal, Bruna Ferreira; Klafke, Guilherme Marcondes; Martins, João Ricardo; Ott, Ricardo; Venzal, José Manuel; Ferreira, Carlos Alexandre Sanchez; Reck, José

    2017-10-01

    Borrelia burgdorferi sensu lato (s.l.) complex includes the agents of Lyme disease/borreliosis in North America, Europe, and Asia, such Borrelia burgdorferi sensu stricto, Borrelia afzelii, Borrelia garinii, Borrelia bavariensis, Borrelia spielmanii, Borrelia bissettiae, and Borrelia mayonii. In 2013 B. burgdorferi s.l. was reported for the first time in the Neotropical region, from Ixodes aragaoi ticks in Uruguayan Pampa. In addition, from 2011 to 2016, 17 suspected human cases of borreliosis-like syndrome were reported in Rio Grande do Sul (RS) state, Brazil, which contains only part of country in the Pampa biome. The goal of this work is to report the results of a state surveillance program conducted in order to investigate the presence of B. burgdorferi s.l. in its classic vector, Ixodes spp. ticks, from the Brazilian Pampa. For this, we searched for Ixodes spp. ticks in 307 rodents from 11 municipalities of RS state. We then tested the ticks for the presence of B. burgdorferi s.l. DNA using PCR analysis. Of 35 Ixodes spp. ticks tested, one larva and one nymph of Ixodes longiscutatus ticks tested positive for Borrelia sp. DNA. The phylogenetic analysis of the flaB fragment grouped our samples (referred as Borrelia sp. haplotype Pampa) into B. burgdorferi s.l. group in a particular branch with other South American haplotypes, and this group was close to Borrelia carolinensis, B. bissettiae, and Borrelia californiensis. This is the first evidence of B. burgdorferi s.l. circulation in ticks of the genus Ixodes in Brazil. These results highlight the need for the implementation of public health policies for the diagnosis and prevention of potential cases of human borreliosis in Brazil. Further studies are needed to fill the gaps in our knowledge of the distribution, pathogenicity, reservoirs, and vectors of these emerging South American B. burgdorferi s.l. haplotypes. Copyright © 2017 Elsevier GmbH. All rights reserved.

  20. Borrelia burgdorferi sensu lato in Ixodes ricinus ticks collected from migratory birds in Southern Norway

    PubMed Central

    2010-01-01

    Background Borrelia burgdorferi sensu lato (s.l.) are the causative agent for Lyme borreliosis (LB), the most common tick-borne disease in the northern hemisphere. Birds are considered important in the global dispersal of ticks and tick-borne pathogens through their migration. The present study is the first description of B. burgdorferi prevalence and genotypes in Ixodes ricinus ticks feeding on birds during spring and autumn migration in Norway. Methods 6538 migratory birds were captured and examined for ticks at Lista Bird Observatory during the spring and the autumn migration in 2008. 822 immature I. ricinus ticks were collected from 215 infested birds. Ticks were investigated for infection with B. burgdorferi s.l. by real-time PCR amplification of the 16S rRNA gene, and B. burgdorferi s.l. were thereafter genotyped by melting curve analysis after real-time PCR amplification of the hbb gene, or by direct sequencing of the PCR amplicon generated from the rrs (16S)-rrl (23S) intergenetic spacer. Results B. burgdorferi s.l. were detected in 4.4% of the ticks. The most prevalent B. burgdorferi genospecies identified were B. garinii (77.8%), followed by B.valaisiana (11.1%), B. afzelii (8.3%) and B. burgdorferi sensu stricto (2.8%). Conclusion Infection rate in ticks and genospecies composition were similar in spring and autumn migration, however, the prevalence of ticks on birds was higher during spring migration. The study supports the notion that birds are important in the dispersal of ticks, and that they may be partly responsible for the heterogeneous distribution of B. burgdorferi s.l. in Europe. PMID:21054890

  1. Morphological and genetic diversity of Rhipicephalus sanguineus sensu lato from the New and Old Worlds

    PubMed Central

    2013-01-01

    Background The taxonomic status of the brown dog tick (Rhipicephalus sanguineus sensu stricto), which has long been regarded as the most widespread tick worldwide and a vector of many pathogens to dogs and humans, is currently under dispute. Methods We conducted a comprehensive morphological and genetic study of 278 representative specimens, which belonged to different species (i.e., Rhipicephalus bursa, R. guilhoni, R. microplus, R. muhsamae, R. pusillus, R. sanguineus sensu lato, and R. turanicus) collected from Europe, Asia, Americas, and Oceania. After detailed morphological examination, ticks were molecularly processed for the analysis of partial mitochondrial (16S rDNA, 12S rDNA, and cox1) gene sequences. Results In addition to R. sanguineus s.l. and R. turanicus, three different operational taxonomic units (namely, R. sp. I, R. sp. II, and R. sp. III) were found on dogs. These operational taxonomical units were morphologically and genetically different from R. sanguineus s.l. and R. turanicus. Ticks identified as R. sanguineus s.l., which corresponds to the so-called “tropical species” (=northern lineage), were found in all continents and genetically it represents a sister group of R. guilhoni. R. turanicus was found on a wide range of hosts in Italy and also on dogs in Greece. Conclusions The tropical species and the temperate species (=southern lineage) are paraphyletic groups. The occurrence of R. turanicus in the Mediterranean region is confirmed. A consensual re-description of R. sanguineus s.s. and R. turanicus will be necessary to solve the taxonomic problems within the so-called R. sanguineus group. PMID:23880226

  2. Detection of Borrelia burgdorferi sensu lato in lizards and their ticks from Hungary.

    PubMed

    Földvári, Gábor; Rigó, Krisztina; Majláthová, Viktória; Majláth, Igor; Farkas, Róbert; Pet'ko, Branislav

    2009-06-01

    To investigate the involvement of lizard species in the natural cycle of Borrelia burgdorferi sensu lato (s.l.) in Hungary, a total of 186 reptiles belonging to three species--126 green lizards (Lacerta viridis), 40 Balkan wall lizards (Podarcis taurica), and 20 sand lizards (Lacerta agilis)--were captured in 2007 and 2008. All ticks removed from the lizards were Ixodes ricinus, either larvae (324/472; 68.6%) or nymphs (148/472; 31.4%). More than half (66/126; 52.4%) of L. viridis individuals were infested, and the prevalence of tick infestation on both the other two species was 35% each. All 472 I. ricinus ticks and tissue samples collected from 134 collar scales and 62 toe clips of lizards were further analyzed for the presence of B. burgdorferi s.l. with polymerase chain reaction. The amplification of B. burgdorferi s.l. DNA was successful in 8% (n = 92) of L. viridis, 9% (n = 32) of P. taurica, and 10% (n = 10) of L. agilis tissue samples. Restriction fragment length polymorphism genotyping identified the species Borrelia lusitaniae in all tested lizard samples. Prevalence of B. burgdorferi s.l. in ticks collected from L. viridis, P. taurica, and L. agilis was 8%, 2%, and 0%, respectively. Most of the infected ticks carried B. lusitaniae (74% of genotyped positives); however, Borrelia afzelii (5%) and B. burgdorferi sensu stricto (21%) were detected in ticks removed from green lizards and Balkan wall lizards, respectively. We conclude that lizards, particularly L. viridis, can be important hosts for I. ricinus larvae and nymphs; thus, they can be regarded as reservoirs of these important pathogen vectors. The role of green lizards has been confirmed, and the implication of Balkan wall lizards is suggested in the natural cycle of B. lusitaniae at our study site.

  3. Morphological and genetic diversity of Rhipicephalus sanguineus sensu lato from the New and Old Worlds.

    PubMed

    Dantas-Torres, Filipe; Latrofa, Maria Stefania; Annoscia, Giada; Giannelli, Alessio; Parisi, Antonio; Otranto, Domenico

    2013-07-23

    The taxonomic status of the brown dog tick (Rhipicephalus sanguineus sensu stricto), which has long been regarded as the most widespread tick worldwide and a vector of many pathogens to dogs and humans, is currently under dispute. We conducted a comprehensive morphological and genetic study of 278 representative specimens, which belonged to different species (i.e., Rhipicephalus bursa, R. guilhoni, R. microplus, R. muhsamae, R. pusillus, R. sanguineus sensu lato, and R. turanicus) collected from Europe, Asia, Americas, and Oceania. After detailed morphological examination, ticks were molecularly processed for the analysis of partial mitochondrial (16S rDNA, 12S rDNA, and cox1) gene sequences. In addition to R. sanguineus s.l. and R. turanicus, three different operational taxonomic units (namely, R. sp. I, R. sp. II, and R. sp. III) were found on dogs. These operational taxonomical units were morphologically and genetically different from R. sanguineus s.l. and R. turanicus. Ticks identified as R. sanguineus s.l., which corresponds to the so-called "tropical species" (= northern lineage), were found in all continents and genetically it represents a sister group of R. guilhoni. R. turanicus was found on a wide range of hosts in Italy and also on dogs in Greece. The tropical species and the temperate species (= southern lineage) are paraphyletic groups. The occurrence of R. turanicus in the Mediterranean region is confirmed. A consensual re-description of R. sanguineus s.s. and R. turanicus will be necessary to solve the taxonomic problems within the so-called R. sanguineus group.

  4. Borrelia burgdorferi sensu lato and co-infections with Anaplasma phagocytophilum and Rickettsia spp. in Ixodes ricinus in Hamburg, Germany.

    PubMed

    May, K; Jordan, D; Fingerle, V; Strube, C

    2015-12-01

    To obtain initial data on Borrelia burgdorferi sensu lato (Spirochaetales: Spirochaetaceae) in Ixodes ricinus (Ixodida: Ixodidae) ticks in Hamburg, Germany, 1400 questing ticks were collected by flagging at 10 different public recreation areas in 2011 and analysed using probe-based quantitative real-time polymerase chain reaction. The overall rate of infection with B. burgdorferi s.l. was 34.1%; 30.0% of adults were infected (36.7% of females and 26.0% of males), as were 34.5% of nymphs. Significant differences in tick infection rates were observed between the spring and summer/autumn months, as well as among sampling locations. Borrelia genospecies identification by reverse line blotting was successful in 43.6% of positive tick samples. The most frequent genospecies was Borrelia garinii/Borrelia bavariensis, followed by Borrelia afzelii, Borrelia valaisiana, B. burgdorferi sensu stricto, Borrelia spielmanii, Borrelia bissettii and Borrelia lusitaniae. Based on previously published data, co-infection of Borrelia and Rickettsiales spp. was determined in 25.8% of ticks. Overall, 22.9% of ticks were co-infected with Rickettsia spp. (Rickettsiales: Rickettsiaceae), 1.7% with Anaplasma phagocytophilum (Rickettsiales: Anaplasmataceae), and 1.2% with both pathogens. Study results show a high prevalence of Borrelia-positive ticks in recreation areas in the northern German city of Hamburg and the potential health risk to humans in these areas should not be underestimated.

  5. Borrelia burgdorferi sensu lato detected in skin of Norwegian mountain hares (Lepus timidus) without signs of dissemination.

    PubMed

    Kjelland, Vivian; Ytrehus, Bjørnar; Vikørren, Turid; Stuen, Snorre; Skarpaas, Tone; Slettan, Audun

    2011-04-01

    The mountain hare (Lepus timidus) population in southern Norway appears to be in decline. Necropsy and laboratory examinations of 36 hares found dead or diseased during 2007-2009 in Vest- and Aust-Agder counties showed that disease and deaths were attributed to multiple causes, with no specific etiology emerging as a cause for population decline. To investigate whether Borrelia burgdorferi sensu lato (s.l.) infection is associated with mortality in mountain hares, tissues and ticks collected from hares were investigated for infection with the spirochete. Borrelia burgdorferi s.l. DNA was not detected in samples from internal organs, whereas Borrelia afzelii, B. burgdorferi sensu stricto (s.s.), and the not-yet-defined Borrelia sp. SV1 were found in skin samples from hares and in adult and nymphal Ixodes ricinus feeding on hares. Only B. burgdorferi s.s. and Borrelia sp. SV1 were detected in larvae feeding on hares. Our results indicate that disseminated Borrelia infection in hares rarely occurs and, presumably, does not play a central role in the suspected population decline. The results also suggest that the mountain hare to some degree functions as a transmission host for B. burgdorferi s.s. and Borrelia sp. SV1.

  6. Tools for Anopheles gambiae Transgenesis.

    PubMed

    Volohonsky, Gloria; Terenzi, Olivier; Soichot, Julien; Naujoks, Daniel A; Nolan, Tony; Windbichler, Nikolai; Kapps, Delphine; Smidler, Andrea L; Vittu, Anaïs; Costa, Giulia; Steinert, Stefanie; Levashina, Elena A; Blandin, Stéphanie A; Marois, Eric

    2015-04-13

    Transgenesis is an essential tool to investigate gene function and to introduce desired characters in laboratory organisms. Setting-up transgenesis in non-model organisms is challenging due to the diversity of biological life traits and due to knowledge gaps in genomic information. Some procedures will be broadly applicable to many organisms, and others have to be specifically developed for the target species. Transgenesis in disease vector mosquitoes has existed since the 2000s but has remained limited by the delicate biology of these insects. Here, we report a compilation of the transgenesis tools that we have designed for the malaria vector Anopheles gambiae, including new docking strains, convenient transgenesis plasmids, a puromycin resistance selection marker, mosquitoes expressing cre recombinase, and various reporter lines defining the activity of cloned promoters. This toolbox contributed to rendering transgenesis routine in this species and is now enabling the development of increasingly refined genetic manipulations such as targeted mutagenesis. Some of the reagents and procedures reported here are easily transferable to other nonmodel species, including other disease vector or agricultural pest insects. Copyright © 2015 Volohonsky et al.

  7. Environmental factors associated with the malaria vectors Anopheles gambiae and Anopheles funestus in Kenya.

    PubMed

    Kelly-Hope, Louise A; Hemingway, Janet; McKenzie, F Ellis

    2009-11-26

    The Anopheles gambiae and Anopheles funestus mosquito species complexes are the primary vectors of Plasmodium falciparum malaria in sub-Saharan Africa. To better understand the environmental factors influencing these species, the abundance, distribution and transmission data from a south-eastern Kenyan study were retrospectively analysed, and the climate, vegetation and elevation data in key locations compared. Thirty villages in Malindi, Kilifi and Kwale Districts with data on An. gambiae sensu strict, Anopheles arabiensis and An. funestus entomological inoculation rates (EIRs), were used as focal points for spatial and environmental analyses. Transmission patterns were examined for spatial autocorrelation using the Moran's I statistic, and for the clustering of high or low EIR values using the Getis-Ord Gi* statistic. Environmental data were derived from remote-sensed satellite sources of precipitation, temperature, specific humidity, Normalized Difference Vegetation Index (NDVI), and elevation. The relationship between transmission and environmental measures was examined using bivariate correlations, and by comparing environmental means between locations of high and low clustering using the Mann-Whitney U test. Spatial analyses indicated positive autocorrelation of An. arabiensis and An. funestus transmission, but not of An. gambiae s.s., which was found to be widespread across the study region. The spatial clustering of high EIR values for An. arabiensis was confined to the lowland areas of Malindi, and for An. funestus to the southern districts of Kilifi and Kwale. Overall, An. gambiae s.s. and An. arabiensis had similar spatial and environmental trends, with higher transmission associated with higher precipitation, but lower temperature, humidity and NDVI measures than those locations with lower transmission by these species and/or in locations where transmission by An. funestus was high. Statistical comparisons indicated that precipitation and temperatures

  8. English Language Teaching Profile: The Gambia.

    ERIC Educational Resources Information Center

    British Council, London (England). English-Teaching Information Centre.

    This profile, in outline form, of the English language teaching situation in the Gambia discusses the role of English within Gambian society and within the educational system. The status of English as the only official language is noted, and its use as medium of instruction at the primary, secondary and teacher-training levels is examined. The…

  9. English Language Teaching Profile: The Gambia.

    ERIC Educational Resources Information Center

    British Council, London (England). English-Teaching Information Centre.

    This profile in outline form of the English language teaching situation in the Gambia discusses the role of English in the community and within the educational system. The number of hours allocated weekly to the teaching of English in the primary school, junior secondary and senior secondary schools and teacher's training college are discussed, as…

  10. The Skills Training Centres in The Gambia.

    ERIC Educational Resources Information Center

    Benett, Yves

    A study surveyed 44 skills centers in The Gambia through a questionnaire, evaluated them regarding vocational training, and conducted on-site research of 17 targeted centers. Findings were as follows: most operated as private organizations; the retention rate was an average of 84%; centers operated with an average student/staff ratio of about 12:1…

  11. Molasses as a source of carbon dioxide for attracting the malaria mosquitoes Anopheles gambiae and Anopheles funestus

    PubMed Central

    2014-01-01

    Background Most odour baits for haematophagous arthropods contain carbon dioxide (CO2). The CO2 is sourced artificially from the fermentation of refined sugar (sucrose), dry ice, pressurized gas cylinders or propane. These sources of CO2 are neither cost-effective nor sustainable for use in remote areas of sub-Saharan Africa. In this study, molasses was evaluated as a potential substrate for producing CO2 used as bait for malaria mosquitoes. Methods The attraction of laboratory-reared and wild Anopheles gambiae complex mosquitoes to CO2 generated from yeast-fermentation of molasses was assessed under semi-field and field conditions in western Kenya. In the field, responses of wild Anopheles funestus were also assessed. Attraction of the mosquitoes to a synthetic mosquito attractant, Mbita blend (comprising ammonia, L-lactic acid, tetradecanoic acid and 3-methyl-1-butanol) when augmented with CO2 generated from yeast fermentation of either molasses or sucrose was also investigated. Results In semi-field, the release rate of CO2 and proportion of An. gambiae mosquitoes attracted increased in tandem with an increase in the quantity of yeast-fermented molasses up to an optimal ratio of molasses and dry yeast. More An. gambiae mosquitoes were attracted to a combination of the Mbita blend plus CO2 produced from fermenting molasses than the Mbita blend plus CO2 from yeast-fermented sucrose. In the field, significantly more female An. gambiae sensu lato mosquitoes were attracted to the Mbita blend augmented with CO2 produced by fermenting 500 g of molasses compared to 250 g of sucrose or 250 g of molasses. Similarly, significantly more An. funestus, Culex and other anopheline mosquito species were attracted to the Mbita blend augmented with CO2 produced from fermenting molasses than the Mbita blend with CO2 produced from sucrose. Augmenting the Mbita blend with CO2 produced from molasses was associated with high catches of blood-fed An. gambiae s.l. and An. funestus

  12. Elimination of Lymphatic Filariasis in The Gambia

    PubMed Central

    Rebollo, Maria P.; Sambou, Sana Malang; Thomas, Brent; Biritwum, Nana-Kwadwo; Jaye, Momodou C.; Kelly-Hope, Louise; Escalada, Alba Gonzalez; Molyneux, David H.; Bockarie, Moses J.

    2015-01-01

    Background The prevalence of Wuchereria bancrofti, which causes lymphatic filariasis (LF) in The Gambia was among the highest in Africa in the 1950s. However, surveys conducted in 1975 and 1976 revealed a dramatic decline in LF endemicity in the absence of mass drug administration (MDA). The decline in prevalence was partly attributed to a significant reduction in mosquito density through the widespread use of insecticidal nets. Based on findings elsewhere that vector control alone can interrupt LF, we asked the question in 2013 whether the rapid scale up in the use of insecticidal nets in The Gambia had interrupted LF transmission. Methodology/Principal Finding We present here the results of three independently designed filariasis surveys conducted over a period of 17 years (1997–2013), and involving over 6000 subjects in 21 districts across all administrative divisions in The Gambia. An immunochromatographic (ICT) test was used to detect W. bancrofti antigen during all three surveys. In 2001, tests performed on stored samples collected between 1997 and 2000, in three divisions, failed to show positive individuals from two divisions that were previously highly endemic for LF, suggesting a decline towards extinction in some areas. Results of the second survey conducted in 2003 showed that LF was no longer endemic in 16 of 21 districts surveyed. The 2013 survey used a WHO recommended LF transmission verification tool involving 3180 6–7 year-olds attending 60 schools across the country. We demonstrated that transmission of W. bancrofti has been interrupted in all 21 districts. Conclusions We conclude that LF transmission may have been interrupted in The Gambia through the extensive use of insecticidal nets for malaria control for decades. The growing evidence for the impact of malaria vector control activities on parasite transmission has been endorsed by WHO through a position statement in 2011 on integrated vector management to control malaria and LF. PMID

  13. Demasculinization of the Anopheles gambiae X chromosome

    PubMed Central

    2012-01-01

    Background In a number of organisms sex-biased genes are non-randomly distributed between autosomes and the shared sex chromosome X (or Z). Studies on Anopheles gambiae have produced conflicting results regarding the underrepresentation of male-biased genes on the X chromosome and it is unclear to what extent sexual antagonism, dosage compensation or X-inactivation in the male germline, the evolutionary forces that have been suggested to affect the chromosomal distribution of sex-biased genes, are operational in Anopheles. Results We performed a meta-analysis of sex-biased gene expression in Anopheles gambiae which provides evidence for a general underrepresentation of male-biased genes on the X-chromosome that increased in significance with the observed degree of sex-bias. A phylogenomic comparison between Drosophila melanogaster, Aedes aegypti and Culex quinquefasciatus also indicates that the Anopheles X chromosome strongly disfavours the evolutionary conservation of male-biased expression and that novel male-biased genes are more likely to arise on autosomes. Finally, we demonstrate experimentally that transgenes situated on the Anopheles gambiae X chromosome are transcriptionally silenced in the male germline. Conclusion The data presented here support the hypothesis that the observed demasculinization of the Anopheles X chromosome is driven by X-chromosome inactivation in the male germline and by sexual antagonism. The demasculinization appears to be the consequence of a loss of male-biased expression, rather than a failure in the establishment or the extinction of male-biased genes. PMID:22607633

  14. Large scale spatial risk and comparative prevalence of Borrelia miyamotoi and Borrelia burgdorferi sensu lato in Ixodes pacificus.

    PubMed

    Padgett, Kerry; Bonilla, Denise; Kjemtrup, Anne; Vilcins, Inger-Marie; Yoshimizu, Melissa Hardstone; Hui, Lucia; Sola, Milagros; Quintana, Miguel; Kramer, Vicki

    2014-01-01

    Borrelia miyamotoi is a newly described emerging pathogen transmitted to people by Ixodes species ticks and found in temperate regions of North America, Europe, and Asia. There is limited understanding of large scale entomological risk patterns of B. miyamotoi and of Borreila burgdorferi sensu stricto (ss), the agent of Lyme disease, in western North America. In this study, B. miyamotoi, a relapsing fever spirochete, was detected in adult (n=70) and nymphal (n=36) Ixodes pacificus ticks collected from 24 of 48 California counties that were surveyed over a 13 year period. Statewide prevalence of B. burgdorferi sensu lato (sl), which includes B. burgdorferi ss, and B. miyamotoi were similar in adult I. pacificus (0.6% and 0.8%, respectively). In contrast, the prevalence of B. burgdorferi sl was almost 2.5 times higher than B. miyamotoi in nymphal I. pacificus (3.2% versus 1.4%). These results suggest similar risk of exposure to B. burgdorferi sl and B. miyamotoi from adult I. pacificus tick bites in California, but a higher risk of contracting B. burgdorferi sl than B. miyamotoi from nymphal tick bites. While regional risk of exposure to these two spirochetes varies, the highest risk for both species is found in north and central coastal California and the Sierra Nevada foothill region, and the lowest risk is in southern California; nevertheless, tick-bite avoidance measures should be implemented in all regions of California. This is the first study to comprehensively evaluate entomologic risk for B. miyamotoi and B. burgdorferi for both adult and nymphal I. pacificus, an important human biting tick in western North America.

  15. The Heterogeneity, Distribution, and Environmental Associations of Borrelia burgdorferi Sensu Lato, the Agent of Lyme Borreliosis, in Scotland

    PubMed Central

    James, Marianne C.; Gilbert, Lucy; Bowman, Alan S.; Forbes, Ken J.

    2014-01-01

    Lyme borreliosis is an emerging infectious human disease caused by the Borrelia burgdorferi sensu lato complex of bacteria with reported cases increasing in many areas of Europe and North America. To understand the drivers of disease risk and the distribution of symptoms, which may improve mitigation and diagnostics, here we characterize the genetics, distribution, and environmental associations of B. burgdorferi s.l. genospecies across Scotland. In Scotland, reported Lyme borreliosis cases have increased almost 10-fold since 2000 but the distribution of B. burgdorferi s.l. is so far unstudied. Using a large survey of over 2200 Ixodes ricinus tick samples collected from birds, mammals, and vegetation across 25 sites we identified four genospecies: Borrelia afzelii (48%), Borrelia garinii (36%), Borrelia valaisiana (8%), and B. burgdorferi sensu stricto (7%), and one mixed genospecies infection. Surprisingly, 90% of the sequence types were novel and, importantly, up to 14% of samples were mixed intra-genospecies co-infections, suggesting tick co-feeding, feeding on multiple hosts, or multiple infections in hosts. B. garinii (hosted by birds) was considerably more genetically diverse than B. afzelii (hosted by small mammals), as predicted since there are more species of birds than small mammals and birds can import strains from mainland Europe. Higher proportions of samples contained B. garinii and B. valaisiana in the west, while B. afzelii and B. garinii were significantly more associated with mixed/deciduous than with coniferous woodlands. This may relate to the abundance of transmission hosts in different regions and habitats. These data on the genetic heterogeneity within and between Borrelia genospecies are a first step to understand pathogen spread and could help explain the distribution of patient symptoms, which may aid local diagnosis. Understanding the environmental associations of the pathogens is critical for rational policy making for disease risk

  16. Borrelia burgdorferi Sensu Lato Spirochetes in Wild Birds in Northwestern California: Associations with Ecological Factors, Bird Behavior and Tick Infestation

    PubMed Central

    Newman, Erica A.; Eisen, Lars; Eisen, Rebecca J.; Fedorova, Natalia; Hasty, Jeomhee M.; Vaughn, Charles; Lane, Robert S.

    2015-01-01

    Although Borrelia burgdorferi sensu lato (s.l.) are found in a great diversity of vertebrates, most studies in North America have focused on the role of mammals as spirochete reservoir hosts. We investigated the roles of birds as hosts for subadult Ixodes pacificus ticks and potential reservoirs of the Lyme disease spirochete B. burgdorferi sensu stricto (s.s.) in northwestern California. Overall, 623 birds representing 53 species yielded 284 I. pacificus larvae and nymphs. We used generalized linear models and zero-inflated negative binomial models to determine associations of bird behaviors, taxonomic relationships and infestation by I. pacificus with borrelial infection in the birds. Infection status in birds was best explained by taxonomic order, number of infesting nymphs, sampling year, and log-transformed average body weight. Presence and counts of larvae and nymphs could be predicted by ground- or bark-foraging behavior and contact with dense oak woodland. Molecular analysis yielded the first reported detection of Borrelia bissettii in birds. Moreover, our data suggest that the Golden-crowned Sparrow (Zonotrichia atricapilla), a non-resident species, could be an important reservoir for B. burgdorferi s.s. Of 12 individual birds (9 species) that carried B. burgdorferi s.l.-infected larvae, no birds carried the same genospecies of B. burgdorferi s.l. in their blood as were present in the infected larvae removed from them. Possible reasons for this discrepancy are discussed. Our study is the first to explicitly incorporate both taxonomic relationships and behaviors as predictor variables to identify putative avian reservoirs of B. burgdorferi s.l. Our findings underscore the importance of bird behavior to explain local tick infestation and Borrelia infection in these animals, and suggest the potential for bird-mediated geographic spread of vector ticks and spirochetes in the far-western United States. PMID:25714376

  17. Inter- and intra-specific pan-genomes of Borrelia burgdorferi sensu lato: genome stability and adaptive radiation

    PubMed Central

    2013-01-01

    Background Lyme disease is caused by spirochete bacteria from the Borrelia burgdorferi sensu lato (B. burgdorferi s.l.) species complex. To reconstruct the evolution of B. burgdorferi s.l. and identify the genomic basis of its human virulence, we compared the genomes of 23 B. burgdorferi s.l. isolates from Europe and the United States, including B. burgdorferi sensu stricto (B. burgdorferi s.s., 14 isolates), B. afzelii (2), B. garinii (2), B. “bavariensis” (1), B. spielmanii (1), B. valaisiana (1), B. bissettii (1), and B. “finlandensis” (1). Results Robust B. burgdorferi s.s. and B. burgdorferi s.l. phylogenies were obtained using genome-wide single-nucleotide polymorphisms, despite recombination. Phylogeny-based pan-genome analysis showed that the rate of gene acquisition was higher between species than within species, suggesting adaptive speciation. Strong positive natural selection drives the sequence evolution of lipoproteins, including chromosomally-encoded genes 0102 and 0404, cp26-encoded ospC and b08, and lp54-encoded dbpA, a07, a22, a33, a53, a65. Computer simulations predicted rapid adaptive radiation of genomic groups as population size increases. Conclusions Intra- and inter-specific pan-genome sizes of B. burgdorferi s.l. expand linearly with phylogenetic diversity. Yet gene-acquisition rates in B. burgdorferi s.l. are among the lowest in bacterial pathogens, resulting in high genome stability and few lineage-specific genes. Genome adaptation of B. burgdorferi s.l. is driven predominantly by copy-number and sequence variations of lipoprotein genes. New genomic groups are likely to emerge if the current trend of B. burgdorferi s.l. population expansion continues. PMID:24112474

  18. Environmental Contamination by Echinococcus granulosus sensu lato Eggs in Relation to Slaughterhouses in Urban and Rural Areas in Tunisia

    PubMed Central

    Chaâbane-Banaoues, Raja; Oudni-M’rad, Myriam; M’rad, Selim; Mezhoud, Habib; Babba, Hamouda

    2016-01-01

    Hydatidosis has become a real concern for health care institutions and animal rearers in Tunisia. The Tunisian endemicity is aggravated by the growing number of dogs and the difficulty of getting rid of contaminated viscera because of the lack of equipment in most slaughterhouses. Therefore, microscopic and molecular tools were applied to evaluate the role of slaughterhouses in canine infection and Echinococcus granulosus sensu lato (s. l.) egg dissemination. Exposure risk to E. granulosus s. l. eggs in urban and rural areas was explored in order to implant preventive and adapted control strategies. Microscopic examinations detected taeniid eggs in 152 amongst 553 fecal samples. The copro-PCR demonstrated that 138 of 152 taeniid samples analyzed were positive for E. granulosus s. l. DNA. PCR-RFLP demonstrated that all isolated samples belonged to E. granulosus sensu stricto (s. s.). An important environmental contamination index (25.0%) by E. granulosus s. l. eggs was demonstrated. The average contamination index from the regions around slaughterhouses (23.3%; 95% CI: 17.7-28.9%) was in the same range as detected in areas located far from slaughterhouses (26.0%, 95% CI: 21.3-30.8%). Echinococcosis endemic areas were extended in both rural (29.9%, 95% CI: 24.8-34.9%) and urban locations (18.1%, 95% CI: 13.0-22.9%). The pathogen dissemination is related neither to the presence/absence of slaughterhouses nor to the location in urban or rural areas, but is probably influenced by human activities (home slaughtering) and behavior towards the infected viscera. PMID:26951990

  19. Proteomic analysis of three Borrelia burgdorferi sensu lato native species and disseminating clones: relevance for Lyme vaccine design.

    PubMed

    Schnell, Gilles; Boeuf, Amandine; Jaulhac, Benoît; Boulanger, Nathalie; Collin, Elody; Barthel, Cathy; De Martino, Sylvie; Ehret-Sabatier, Laurence

    2015-04-01

    Lyme borreliosis is the most important vector-borne disease in the Northern hemisphere. It is caused by Borrelia burgdorferi sensu lato bacteria transmitted to humans by the bite of hard ticks, Ixodes spp. Although antibiotic treatments are efficient in the early stage of the infection, a significant number of patients develop disseminated manifestations (articular, neurological, and cutaneous) due to unnoticed or absence of erythema migrans, or to inappropriate treatment. Vaccine could be an efficient approach to decrease Lyme disease incidence. We have developed a proteomic approach based on a one dimensional gel electrophoresis followed by LC-MS/MS strategy to identify new vaccine candidates. We analyzed a disseminating clone and the associated wild-type strain for each major pathogenic Borrelia species: B. burgdorferi sensu stricto, B. garinii, and B. afzelii. We identified specific proteins and common proteins to the disseminating clones of the three main species. In parallel, we used a spectral counting strategy to identify upregulated proteins common to the clones. Finally, 40 proteins were found that could potentially be involved in bacterial virulence and of interest in the development of a new vaccine. We selected the three proteins specifically detected in the disseminating clones of the three Borrelia species and checked by RT-PCR whether they are expressed in mouse skin upon B. burgdorferi ss inoculation. Interestingly, BB0566 appears as a potential vaccine candidate. All MS data have been deposited in the ProteomeXchange with identifier PXD000876 (http://proteomecentral.proteomexchange.org/dataset/PXD000876). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Large Scale Spatial Risk and Comparative Prevalence of Borrelia miyamotoi and Borrelia burgdorferi Sensu Lato in Ixodes pacificus

    PubMed Central

    Padgett, Kerry; Bonilla, Denise; Kjemtrup, Anne; Vilcins, Inger-Marie; Yoshimizu, Melissa Hardstone; Hui, Lucia; Sola, Milagros; Quintana, Miguel; Kramer, Vicki

    2014-01-01

    Borrelia miyamotoi is a newly described emerging pathogen transmitted to people by Ixodes species ticks and found in temperate regions of North America, Europe, and Asia. There is limited understanding of large scale entomological risk patterns of B. miyamotoi and of Borreila burgdorferi sensu stricto (ss), the agent of Lyme disease, in western North America. In this study, B. miyamotoi, a relapsing fever spirochete, was detected in adult (n = 70) and nymphal (n = 36) Ixodes pacificus ticks collected from 24 of 48 California counties that were surveyed over a 13 year period. Statewide prevalence of B. burgdorferi sensu lato (sl), which includes B. burgdorferi ss, and B. miyamotoi were similar in adult I. pacificus (0.6% and 0.8%, respectively). In contrast, the prevalence of B. burgdorferi sl was almost 2.5 times higher than B. miyamotoi in nymphal I. pacificus (3.2% versus 1.4%). These results suggest similar risk of exposure to B. burgdorferi sl and B. miyamotoi from adult I. pacificus tick bites in California, but a higher risk of contracting B. burgdorferi sl than B. miyamotoi from nymphal tick bites. While regional risk of exposure to these two spirochetes varies, the highest risk for both species is found in north and central coastal California and the Sierra Nevada foothill region, and the lowest risk is in southern California; nevertheless, tick-bite avoidance measures should be implemented in all regions of California. This is the first study to comprehensively evaluate entomologic risk for B. miyamotoi and B. burgdorferi for both adult and nymphal I. pacificus, an important human biting tick in western North America. PMID:25333277

  1. Borrelia burgdorferi sensu lato spirochetes in wild birds in northwestern California: associations with ecological factors, bird behavior and tick infestation.

    PubMed

    Newman, Erica A; Eisen, Lars; Eisen, Rebecca J; Fedorova, Natalia; Hasty, Jeomhee M; Vaughn, Charles; Lane, Robert S

    2015-01-01

    Although Borrelia burgdorferi sensu lato (s.l.) are found in a great diversity of vertebrates, most studies in North America have focused on the role of mammals as spirochete reservoir hosts. We investigated the roles of birds as hosts for subadult Ixodes pacificus ticks and potential reservoirs of the Lyme disease spirochete B. burgdorferi sensu stricto (s.s.) in northwestern California. Overall, 623 birds representing 53 species yielded 284 I. pacificus larvae and nymphs. We used generalized linear models and zero-inflated negative binomial models to determine associations of bird behaviors, taxonomic relationships and infestation by I. pacificus with borrelial infection in the birds. Infection status in birds was best explained by taxonomic order, number of infesting nymphs, sampling year, and log-transformed average body weight. Presence and counts of larvae and nymphs could be predicted by ground- or bark-foraging behavior and contact with dense oak woodland. Molecular analysis yielded the first reported detection of Borrelia bissettii in birds. Moreover, our data suggest that the Golden-crowned Sparrow (Zonotrichia atricapilla), a non-resident species, could be an important reservoir for B. burgdorferi s.s. Of 12 individual birds (9 species) that carried B. burgdorferi s.l.-infected larvae, no birds carried the same genospecies of B. burgdorferi s.l. in their blood as were present in the infected larvae removed from them. Possible reasons for this discrepancy are discussed. Our study is the first to explicitly incorporate both taxonomic relationships and behaviors as predictor variables to identify putative avian reservoirs of B. burgdorferi s.l. Our findings underscore the importance of bird behavior to explain local tick infestation and Borrelia infection in these animals, and suggest the potential for bird-mediated geographic spread of vector ticks and spirochetes in the far-western United States.

  2. Vigna (Leguminosae) sensu lato: the names and identities of the American segregate genera.

    PubMed

    Delgado-Salinas, Alfonso; Thulin, Mats; Pasquet, Rémy; Weeden, Norm; Lavin, Matt

    2011-10-01

    The legume genus Vigna and close relatives have highly elaborated floral morphologies that involve the coiling, bending, and intricate connection of flower parts. Banners, levers, platforms, and pumps have evolved that attract pollinators and then manipulate their movement. Given this three-dimensional floral complexity, the taxonomy of Vigna and relatives has been confounded by the study of mostly two-dimensional museum specimens. A molecular phylogenetic analysis was undertaken in the effort to resolve long-standing taxonomic questions centered on floral morphology. The phylogenetic analysis included cpDNA trnK and nuclear ribosomal ITS/5.8S (ITS) sequence variation. The American species were comprehensively sampled and outgroups included Old World relatives. The trnK and ITS data analyses concurred in resolving six well-supported clades of American Vigna that are most closely related to other American genera: Dolichopsis, Macroptilium, Mysanthus, Oryxis, Oxyrhynchus, Phaseolus, Ramirezella, and Strophostyles. These 14 American clades ranked here as genera are resolved as sister to a clade comprising the mainly Old World species of Vigna. American Vigna clades were reassigned to the genera Ancistrotropis, Cochliasanthus, Condylostylis, Leptospron, Sigmoidotropis, and the newly described Helicotropis. Vigna sensu stricto in the Americas now includes relatively few and mostly pantropical species. Elaborate floral asymmetries are readily used to apomorphically diagnose nearly all of the American genera. The age estimates of the extant diversification of the American and its Old World sister clade are approximately coeval at ca. 6-7 million yr, which belies much greater floral variation in the Americas.

  3. An alternative method for the analysis of melanin production in Cryptococcus neoformans sensu lato and Cryptococcus gattii sensu lato.

    PubMed

    Brilhante, Raimunda S N; España, Jaime D A; de Alencar, Lucas P; Pereira, Vandbergue S; Castelo-Branco, Débora de S C M; Pereira-Neto, Waldemiro de A; Cordeiro, Rossana de A; Sidrim, José J C; Rocha, Marcos F G

    2017-10-01

    Melanin is an important virulence factor for several microorganisms, including Cryptococcus neoformans sensu lato and Cryptococcus gattii sensu lato, thus, the assessment of melanin production and its quantification may contribute to the understanding of microbial pathogenesis. The objective of this study was to standardise an alternative method for the production and indirect quantification of melanin in C. neoformans sensu lato and C. gattii sensu lato. Eight C. neoformans sensu lato and three C. gattii sensu lato, identified through URA5 methodology, Candida parapsilosis ATCC 22019 (negative control) and one Hortaea werneckii (positive control) were inoculated on minimal medium agar with or without L-DOPA, in duplicate, and incubated at 35°C, for 7 days. Pictures were taken from the third to the seventh day, under standardised conditions in a photographic chamber. Then, photographs were analysed using grayscale images. All Cryptococcus spp. strains produced melanin after growth on minimal medium agar containing L-DOPA. C. parapsilosis ATCC 22019 did not produce melanin on medium containing L-DOPA, while H. werneckii presented the strongest pigmentation. This new method allows the indirect analysis of melanin production through pixel quantification in grayscale images, enabling the study of substances that can modulate melanin production. © 2017 Blackwell Verlag GmbH.

  4. Exposure to disinfectants (soap or hydrogen peroxide) increases tolerance to permethrin in Anopheles gambiae populations from the city of Yaoundé, Cameroon

    PubMed Central

    2014-01-01

    Background The rapid expansion of insecticide resistance is limiting the efficiency of malaria vector control interventions. However, current knowledge of factors inducing pyrethroid resistance remains incomplete. In the present study, the role of selection at the larval stage by disinfectants, such as soap and hydrogen peroxide (H2O2), on adult mosquito resistance to permethrin was investigated. Methods Field Anopheles gambiae sensu lato larvae, were exposed to variable concentrations of soap and H2O2. Larvae surviving to acute toxicity assays after 24 hours were reared to the adult stage and exposed to permethrin. The susceptibility level of adults was compared to the untreated control group. The effect of soap or hydrogen peroxide selection on the length of larval development and emergence rate was assessed. Result Larval bioassays analysis showed a more acute effect of hydrogen peroxide on mosquito larvae compared to soap. The regression lines describing the dose mortality profile showed higher mean and variance to hydrogen peroxide than to soap. The duration of larval development (<5 days) and adults emergence rates (1 to 77%) were shorter and lower compare to control. Anopheles gambiae s.l. larvae surviving to selection with either soap or hydrogen peroxide or both, produced adults who were up to eight-times more resistant to permethrin than mosquitoes from the untreated control group. Conclusion The present study shows that selective pressure exerted by non-insecticidal compounds such as soap and hydrogen peroxide affect An. gambiae s.l. tolerance to pyrethroids. This requires further studies with regard to the adaptation of An. gambiae s.l. to polluted habitats across sub-Saharan Africa cities. PMID:25086741

  5. Exposure to disinfectants (soap or hydrogen peroxide) increases tolerance to permethrin in Anopheles gambiae populations from the city of Yaoundé, Cameroon.

    PubMed

    Antonio-Nkondjio, Christophe; Youmsi-Goupeyou, Marlene; Kopya, Edmond; Tene-Fossog, Billy; Njiokou, Flobert; Costantini, Carlo; Awono-Ambene, Parfait

    2014-08-03

    The rapid expansion of insecticide resistance is limiting the efficiency of malaria vector control interventions. However, current knowledge of factors inducing pyrethroid resistance remains incomplete. In the present study, the role of selection at the larval stage by disinfectants, such as soap and hydrogen peroxide (H2O2), on adult mosquito resistance to permethrin was investigated. Field Anopheles gambiae sensu lato larvae, were exposed to variable concentrations of soap and H2O2. Larvae surviving to acute toxicity assays after 24 hours were reared to the adult stage and exposed to permethrin. The susceptibility level of adults was compared to the untreated control group. The effect of soap or hydrogen peroxide selection on the length of larval development and emergence rate was assessed. Larval bioassays analysis showed a more acute effect of hydrogen peroxide on mosquito larvae compared to soap. The regression lines describing the dose mortality profile showed higher mean and variance to hydrogen peroxide than to soap. The duration of larval development (<5 days) and adults emergence rates (1 to 77%) were shorter and lower compare to control. Anopheles gambiae s.l. larvae surviving to selection with either soap or hydrogen peroxide or both, produced adults who were up to eight-times more resistant to permethrin than mosquitoes from the untreated control group. The present study shows that selective pressure exerted by non-insecticidal compounds such as soap and hydrogen peroxide affect An. gambiae s.l. tolerance to pyrethroids. This requires further studies with regard to the adaptation of An. gambiae s.l. to polluted habitats across sub-Saharan Africa cities.

  6. Human seroprevalence against Borrelia burgdorferi sensu lato in two comparable regions of the eastern Alps is not correlated to vector infection rates.

    PubMed

    Sonnleitner, S T; Margos, G; Wex, F; Simeoni, J; Zelger, R; Schmutzhard, E; Lass-Flörl, C; Walder, G

    2015-04-01

    Seroprevalences were determined by testing sera of 1607 blood donors from North, East, and South Tyrol. In the Tyrols, the continental divide delimitates areas with high seroprevalences of IgG antibodies against Borrelia burgdorferi sensu lato in the North (7.2%) from areas with low seroprevalences in the South (1.5%). To determine Borrelia prevalences in unfed Ixodes ricinus ticks, 755 questing ticks were tested by PCR. Prevalences in nymphal and adult ticks were found to be 19.7% (n=132) and 21.5% (n=205) in North Tyrol and 23% (n=43) and 23.7% (n=376) in South Tyrol, respectively. Sequencing of 46 Borrelia-positive ticks yielded 74% Borrelia (B.) afzelii, 11% B. garinii, 7% B. lusitaniae, 7% B. burgdorferi sensu stricto, and 2% B. valaisiana infections. Distinct genetic clusters could not be delimitated on either side of the continental divide. This study describes occurrence and geographic dispersion of Borrelia spp. in the Tyrols, discusses possible reasons for significant differences in human seroprevalence, and indicates that prevalence of Borrelia in vector ticks is not a direct predictive factor for the local seroprevalence in humans.

  7. Central nervous system infection due to Cryptococcus gattii sensu lato in India: Analysis of clinical features, molecular profile and antifungal susceptibility.

    PubMed

    Lahiri Mukhopadhyay, Shayanki; Bahubali, Veenakumari H; Manjunath, Netravathi; Swaminathan, Aarthi; Maji, Sayani; Palaniappan, Marimuthu; Parthasarathy, Satishchandra; Chandrashekar, Nagarathna

    2017-07-23

    Cryptococcus gattii species complex has evolved as a pathogen in the last two decades causing infection among both immunocompetent and immunocompromised hosts. We aimed to analyse the clinical features of CNS infection caused by C. gattii sensu lato, molecular and antifungal susceptibility profile of this pathogen. Cases diagnosed to have CNS cryptococcosis were included in the study. Cryptococcus recovered from patient's specimen was identified by standard protocol. Species confirmation, mating type and molecular type determination were performed by PCR based methods. Antifungal susceptibility was tested in VITEK2C to amphotericin B, 5-flucytosine, fluconazole and voriconazole. Among 199 cases, 20 (10%) were due to C. gattii, comprising of 75% cryptococcal meningitis and 25% cryptococcoma cases. Young adult males were commonly affected. Headache and vomiting were prominent symptoms and 50% were immunocompromised. Among the isolates, 75%, 20% and 5% were C. tetragattii, C. gattii sensu stricto and C. bacillisporus respectively and all had mating type α. Four (20%) isolates of C. tetragattii and the only isolate of C. bacillisporus were resistant to fluconazole. The most common species isolated from south India is C. tetragattii. The study contributes to the epidemiology of C. gattii and reiterates the need for genotyping and antifungal susceptibility testing. © 2017 Blackwell Verlag GmbH.

  8. Structure of Pollen Apertures in the Detarieae sensu stricto (Leguminosae: Caesalpinioideae), with Particular Reference to Underlying Structures (Zwischenkörper)

    PubMed Central

    BANKS, HANNAH

    2003-01-01

    This study presents the pollen aperture morphology of 148 out of approx. 200 species in 16 genera of the Detarieae s.s. and 13 related genera, investigated with light microscopy, scanning electron microscopy and transmission electron microscopy, using various staining techniques. Features of detarioid legume pollen apertures are described, illustrated and discussed in relation to function and phylogeny. Protruding apertures in the mature pollen grains of taxa in the Detarieae s.s are associated with underlying structures composed of pectic substances called ‘Zwischenkörper’. This is the first report of Zwischenkörper in legume pollen. A review of previous literature on Zwischenkörper, evidence of how they differ from onci, and a discussion of developmental origins, terminology and function, is given. Zwischenkörper occur in pollen of Daniellia, Eurypetalum, Eperua, Augouardia, Stemonocoleus, Baikiaea, Copaifera, Pseudosindora, Detarium, Sindora, Sindoropsis, Tessmannia, Gilletiodendron, Hylodendron, Hymenaea, Peltogyne and Guibourtia of the Detarieae s.s. clade of recent molecular analyses. Exinous projections and/or bridges are present over the centre of apertures in the pollen of Sindora, Copaifera, Detarium, Pseudosindora, Hylodendron and Sindoropsis, and may cover the Zwischenkörper of live pollen. Zwischenkörper also occur in the closely related genus Barnebydendron, the sister genus to the Detarieae s.l. clade Goniorrhachis, and also Cercis of the sister clade to the Detarieae s.l. plus Goniorrhachis. A modified form of Zwischenkörper occurs in the pollen of Schotia. Zwischenkörper were not detected in the genera Colophospermum, Prioria, Gossweilerodendron, Oxystigma, Kingiodendron and Hardwickia of the Prioria clade, or in Endertia, Lysidice and Saraca of the Amherstieae clade. None of these taxa have protruding apertures. PMID:12881406

  9. Characterization, Ecological Distribution, and Population Dynamics of Saccharomyces Sensu Stricto Killer Yeasts in the Spontaneous Grape Must Fermentations of Southwestern Spain

    PubMed Central

    Maqueda, Matilde; Zamora, Emiliano; Álvarez, María L.

    2012-01-01

    Killer yeasts secrete protein toxins that are lethal to sensitive strains of the same or related yeast species. Among the four types of Saccharomyces killer yeasts already described (K1, K2, K28, and Klus), we found K2 and Klus killer yeasts in spontaneous wine fermentations from southwestern Spain. Both phenotypes were encoded by medium-size double-stranded RNA (dsRNA) viruses, Saccharomyces cerevisiae virus (ScV)-M2 and ScV-Mlus, whose genome sizes ranged from 1.3 to 1.75 kb and from 2.1 to 2.3 kb, respectively. The K2 yeasts were found in all the wine-producing subareas for all the vintages analyzed, while the Klus yeasts were found in the warmer subareas and mostly in the warmer ripening/harvest seasons. The middle-size isotypes of the M2 dsRNA were the most frequent among K2 yeasts, probably because they encoded the most intense K2 killer phenotype. However, the smallest isotype of the Mlus dsRNA was the most frequent for Klus yeasts, although it encoded the least intense Klus killer phenotype. The killer yeasts were present in most (59.5%) spontaneous fermentations. Most were K2, with Klus being the minority. The proportion of killer yeasts increased during fermentation, while the proportion of sensitive yeasts decreased. The fermentation speed, malic acid, and wine organoleptic quality decreased in those fermentations where the killer yeasts replaced at least 15% of a dominant population of sensitive yeasts, while volatile acidity and lactic acid increased, and the amount of bacteria in the tumultuous and the end fermentation stages also increased in an unusual way. PMID:22101056

  10. The Psilostomidae Looss, 1900 (sensu stricto) (Digenea: Echinostomatoidea): description of three new genera and a key to the genera of the family.

    PubMed

    Kudlai, Olena; Kostadinova, Aneta; Pulis, Eric E; Tkach, Vasyl V

    2017-01-01

    Three new psilostomid genera, Byrdtrema n. g., Longisaccus n. g. and Macracetabulum n. g., each with a single species, are described from ducks, Aix sponsa (L.) and Bucephala albeola (L.) in North America. Byrdtrema n. g. and Macracetabulum n. g. possess a bipartite seminal vesicle and share this character with four psilostomid genera, Grysoma Byrd, Bogitsh & Maples, 1961, Neopsilotrema Kudlai, Pulis, Kostadinova & Tkach, 2016, Psilostomum Looss, 1899 and Psilotornus Byrd & Prestwood, 1969. Byrdtrema n. g. differs from Macracetabulum n. g. in the shape of the body (elongate vs elongate-oval); the position of the ventral sucker (in first third of body vs just pre-equatorial); the shorter forebody; as well as in the smaller size of the eggs in relation to body length. Both new genera differ from (i) Grysoma by the nature of the vitellarium (large, compact follicles with small vitelline cells vs weakly defined follicles with large vitelline cells, respectively) and the smaller size of the eggs in relation to body length; (ii) Psilostomum in the posterior extend of the cirrus-sac in relation to ventral sucker (slightly posterior vs more posterior), the location of the genital pore (at the level of oesophagus vs just postbifurcal), the shorter length of uterine and longer post-testicular fields in relation to body length, and the anterior limits of vitellarium (at the level of ventral sucker vs posterior to ventral sucker); (iii) Psilotornus by the presence of a muscular pharynx (vs absent or rudimentary) and the location of the cirrus-sac (antero-dorsal to ventral sucker or more posterior vs entirely anterior to ventral sucker) and ovary (in hindbody vs in forebody). Byrdtrema n. g. differs from Neopsilotrema in the shape of the body (elongate vs subspherical to elongate-oval) and ventral sucker (elongate-oval vs subspherical to transversely oval), the shorter forebody and smaller eggs in relation to body length. Macracetabulum n. g. differs from Neopsilotrema by the shape of the ventral sucker (elongate-oval vs subspherical to transversely oval), the anterior limits of vitellarium (level of middle of ventral sucker vs level of intestinal bifurcation or anterior testis); and the slightly smaller size of eggs in relation to body length. Among the psilostomid genera, Longisaccus n. g. shows close affinities to Psilochasmus Lühe, 1909 in the presence of the long cirrus-sac and tubular internal seminal vesicle but can be clearly distinguished from the latter by the absence of the retractile tail-like process. In combination with molecular data, the above differences justify the recognition of three new genera. A key to the genera of the Psilostomidae is provided.

  11. Characterization, ecological distribution, and population dynamics of Saccharomyces sensu stricto killer yeasts in the spontaneous grape must fermentations of southwestern Spain.

    PubMed

    Maqueda, Matilde; Zamora, Emiliano; Álvarez, María L; Ramírez, Manuel

    2012-02-01

    Killer yeasts secrete protein toxins that are lethal to sensitive strains of the same or related yeast species. Among the four types of Saccharomyces killer yeasts already described (K1, K2, K28, and Klus), we found K2 and Klus killer yeasts in spontaneous wine fermentations from southwestern Spain. Both phenotypes were encoded by medium-size double-stranded RNA (dsRNA) viruses, Saccharomyces cerevisiae virus (ScV)-M2 and ScV-Mlus, whose genome sizes ranged from 1.3 to 1.75 kb and from 2.1 to 2.3 kb, respectively. The K2 yeasts were found in all the wine-producing subareas for all the vintages analyzed, while the Klus yeasts were found in the warmer subareas and mostly in the warmer ripening/harvest seasons. The middle-size isotypes of the M2 dsRNA were the most frequent among K2 yeasts, probably because they encoded the most intense K2 killer phenotype. However, the smallest isotype of the Mlus dsRNA was the most frequent for Klus yeasts, although it encoded the least intense Klus killer phenotype. The killer yeasts were present in most (59.5%) spontaneous fermentations. Most were K2, with Klus being the minority. The proportion of killer yeasts increased during fermentation, while the proportion of sensitive yeasts decreased. The fermentation speed, malic acid, and wine organoleptic quality decreased in those fermentations where the killer yeasts replaced at least 15% of a dominant population of sensitive yeasts, while volatile acidity and lactic acid increased, and the amount of bacteria in the tumultuous and the end fermentation stages also increased in an unusual way.

  12. Two haplotype clusters of Echinococcus granulosus sensu stricto in northern Iraq (Kurdistan region) support the hypothesis of a parasite cradle in the Middle East.

    PubMed

    Hassan, Zuber Ismael; Meerkhan, Azad Abdullah; Boufana, Belgees; Hama, Abdullah A; Ahmed, Bayram Dawod; Mero, Wijdan Mohammed Salih; Orsten, Serra; Interisano, Maria; Pozio, Edoardo; Casulli, Adriano

    2017-08-01

    Human cystic echinococcosis (CE) caused by Echinococcus granulosus s.s. is a major public health problem in Iraqi Kurdistan with a reported surgical incidence of 6.3 per 100,000 Arbil inhabitants. A total of 125 Echinococcus isolates retrieved from sheep, goats and cattle were used in this study. Our aim was to determine species/genotypes infecting livestock in Iraqi Kurdistan and examine intraspecific variation and population structure of Echinococcus granulosus s.s. in this region and relate it to that of other regions worldwide. Using nucleotide sequences of the mitochondrial cytochrome c oxidase subunit 1 (cox 1) we identified E. granulosus s.s. as the cause of hydatidosis in all examined animals. The haplotype network displayed a double-clustered topology with two main E. granulosus s.s. haplotypes, (KU05) and (KU33). The 'founder' haplotype (KU05) confirmed the presence of a common lineage of non-genetically differentiated populations as inferred by the low non-significant fixation index values. Overall diversity and neutrality indices indicated demographic expansion. We used E. granulosus s.s. nucleotide sequences from GenBank to draw haplotype networks for the Middle East (Iran, Jordan and Turkey), Europe (Albania, Greece, Italy, Romania and Spain), China, Mongolia, Russia, South America (Argentina, Brazil, Chile and Mexico) and Tunisia. Networks with two haplotype clusters like that reported here for Iraqi Kurdistan were seen for the Middle East, Europe, Mongolia, Russia and Tunisia using both 827bp and 1609bp cox1 nucleotide sequences, whereas a star-like network was observed for China and South America. We hypothesize that the double clustering seen at what is generally assumed to be the cradle of domestication may have emerged independently and dispersed from the Middle East to other regions and that haplotype (KU33) may be the main haplotype within a second cluster in the Middle East from where it has spread into Europe, Mongolia, Russia and North Africa. Further studies using metacestodes of human origin are required to investigate the biological importance of E. granulosus s.s. haplotypes/clusters and their association, if any with clinical manifestations of CE infection. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Heterogeneity of Borrelia burgdorferi Sensu Stricto Population and Its Involvement in Borrelia Pathogenicity: Study on Murine Model with Specific Emphasis on the Skin Interface.

    PubMed

    Kern, Aurélie; Schnell, Gilles; Bernard, Quentin; Bœuf, Amandine; Jaulhac, Benoît; Collin, Elody; Barthel, Cathy; Ehret-Sabatier, Laurence; Boulanger, Nathalie

    2015-01-01

    Lyme disease is a multisystemic disorder caused by B. burgdorferi sl. The molecular basis for specific organ involvement is poorly understood. The skin plays a central role in the development of Lyme disease as the entry site of B. burgdorferi in which specific clones are selected before dissemination. We compared the skin inflammatory response (antimicrobial peptides, cytokines and chemokines) elicited by spirochete populations recovered from patients presenting different clinical manifestations. Remarkably, these spirochete populations induced different inflammatory profiles in the skin of C3H/HeN mice. As spirochete population transmitted into the host skin is heterogeneous, we isolated one bacterial clone from a population recovered from a patient with neuroborreliosis and compared its virulence to the parental population. This clone elicited a strong cutaneous inflammatory response characterized by MCP-1, IL-6 and antimicrobial peptides induction. Mass spectrometry of this clone revealed 110 overexpressed proteins when compared with the parental population. We further focused on the expression of nine bacterial surface proteins. bb0347 coding for a protein that interacts with host fibronectin, allowing bacterial adhesion to vascular endothelium and extracellular matrix, was found to be induced in host skin with another gene bb0213 coding for a hypothetical protein. These findings demonstrate the heterogeneity of the B. burgdorferi ss population and the complexity of the interaction involved early in the skin.

  14. Intraspecific concerted evolution of the rDNA ITS1 in Anopheles farauti sensu stricto (Diptera: Culicidae) reveals recent patterns of population structure.

    PubMed

    Bower, James E; Dowton, Mark; Cooper, Robert D; Beebe, Nigel W

    2008-10-01

    We examined the intraindividual variation present in the first ribosomal internal transcribed spacer (ITS1) of Anopheles farauti to determine the level of divergence among populations for this important malarial vector. We isolated 187 clones from 70 individuals and found regional variation among four internal tandem repeats. The data were partitioned prior to analysis given the presence of a paralogous ITS2 sequence, called the 5'-subrepeat, inserted in the ITS1 of most clones. A high level of homogenization and population differentiation was observed for this repeat, which indicates a higher rate of turnover relative to the adjacent 'core' region. Bayesian analysis was performed using several substitutional models on both a combined and a partitioned data set. On the whole, the ITS1 phylogeny and geographic origin of the samples appear to be congruent. Some interesting exceptions indicate the spread of variant repeats between populations and the retention of ancestral polymorphism. Our data clearly demonstrate concerted evolution at the intraspecific level despite intraindividual variation and a complex internal repeat structure from a species that occupies a continuous coastal distribution. A high rate of genomic turnover in combination with a high level of sequence divergence appears to be a major factor leading to its concerted evolution within these populations.

  15. Application of DNA Bar Codes for Screening of Industrially Important Fungi: the Haplotype of Trichoderma harzianum Sensu Stricto Indicates Superior Chitinase Formation▿

    PubMed Central

    Nagy, Viviana; Seidl, Verena; Szakacs, George; Komoń-Zelazowska, Monika; Kubicek, Christian P.; Druzhinina, Irina S.

    2007-01-01

    Selection of suitable strains for biotechnological purposes is frequently a random process supported by high-throughput methods. Using chitinase production by Hypocrea lixii/Trichoderma harzianum as a model, we tested whether fungal strains with superior enzyme formation may be diagnosed by DNA bar codes. We analyzed sequences of two phylogenetic marker loci, internal transcribed spacer 1 (ITS1) and ITS2 of the rRNA-encoding gene cluster and the large intron of the elongation factor 1-alpha gene, tef1, from 50 isolates of H. lixii/T. harzianum, which were also tested to determine their ability to produce chitinases in solid-state fermentation (SSF). Statistically supported superior chitinase production was obtained for strains carrying one of the observed ITS1 and ITS2 and tef1 alleles corresponding to an allele of T. harzianum type strain CBS 226.95. A tef1-based DNA bar code tool, TrichoCHIT, for rapid identification of these strains was developed. The geographic origin of the strains was irrelevant for chitinase production. The improved chitinase production by strains containing this haplotype was not due to better growth on N-acetyl-β-d-glucosamine or glucosamine. Isoenzyme electrophoresis showed that neither the isoenzyme profile of N-acetyl-β-glucosaminidases or the endochitinases nor the intensity of staining of individual chitinase bands correlated with total chitinase in the culture filtrate. The superior chitinase producers did not exhibit similarly increased cellulase formation. Biolog Phenotype MicroArray analysis identified lack of N-acetyl-β-d-mannosamine utilization as a specific trait of strains with the chitinase-overproducing haplotype. This observation was used to develop a plate screening assay for rapid microbiological identification of the strains. The data illustrate that desired industrial properties may be an attribute of certain populations within a species, and screening procedures should thus include a balanced mixture of all genotypes of a given species. PMID:17827332

  16. Application of DNA bar codes for screening of industrially important fungi: the haplotype of Trichoderma harzianum sensu stricto indicates superior chitinase formation.

    PubMed

    Nagy, Viviana; Seidl, Verena; Szakacs, George; Komoń-Zelazowska, Monika; Kubicek, Christian P; Druzhinina, Irina S

    2007-11-01

    Selection of suitable strains for biotechnological purposes is frequently a random process supported by high-throughput methods. Using chitinase production by Hypocrea lixii/Trichoderma harzianum as a model, we tested whether fungal strains with superior enzyme formation may be diagnosed by DNA bar codes. We analyzed sequences of two phylogenetic marker loci, internal transcribed spacer 1 (ITS1) and ITS2 of the rRNA-encoding gene cluster and the large intron of the elongation factor 1-alpha gene, tef1, from 50 isolates of H. lixii/T. harzianum, which were also tested to determine their ability to produce chitinases in solid-state fermentation (SSF). Statistically supported superior chitinase production was obtained for strains carrying one of the observed ITS1 and ITS2 and tef1 alleles corresponding to an allele of T. harzianum type strain CBS 226.95. A tef1-based DNA bar code tool, TrichoCHIT, for rapid identification of these strains was developed. The geographic origin of the strains was irrelevant for chitinase production. The improved chitinase production by strains containing this haplotype was not due to better growth on N-acetyl-beta-D-glucosamine or glucosamine. Isoenzyme electrophoresis showed that neither the isoenzyme profile of N-acetyl-beta-glucosaminidases or the endochitinases nor the intensity of staining of individual chitinase bands correlated with total chitinase in the culture filtrate. The superior chitinase producers did not exhibit similarly increased cellulase formation. Biolog Phenotype MicroArray analysis identified lack of N-acetyl-beta-D-mannosamine utilization as a specific trait of strains with the chitinase-overproducing haplotype. This observation was used to develop a plate screening assay for rapid microbiological identification of the strains. The data illustrate that desired industrial properties may be an attribute of certain populations within a species, and screening procedures should thus include a balanced mixture of all genotypes of a given species.

  17. Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry Can Accurately Differentiate between Mycobacterium masilliense (M. abscessus subspecies bolletti) and M. abscessus (Sensu Stricto)

    PubMed Central

    Teng, Shih-Hua; Chen, Chung-Ming; Lee, Meng-Rui; Lee, Tai-Fen; Chien, Kun-Yi; Teng, Lee-Jene

    2013-01-01

    Among 36 Mycobacterium masilliense and 22 M. abscessus isolates identified by erm(41) PCR and sequencing analysis of rpoB and 23S rRNA genes, the rate of accurate differentiation between these two subspecies was 100% by cluster analysis of spectra generated by Bruker Biotyper matrix-assisted laser desorption ionization–time of flight mass spectrometry. PMID:23824775

  18. Molecular phylogeny of the Ceratosolen species pollinating Ficus of the subgenus Sycomorus sensu stricto: biogeographical history and origins of the species-specificity breakdown cases.

    PubMed

    Kerdelhue, C; Le Clainche, I; Rasplus, J Y

    1999-04-01

    The 14 species of Ficus of the subgenus Sycomorus (Moraceae) are invariably pollinated by Ceratosolen species (Hym. Chalcidoidea), which in turn reproduce in the fig florets. They are distributed mostly in continental Africa, Madagascar, and the Mascarene and Comoro Islands, but 1 species extends its geographical range all over the Oriental region. Fig-pollinator relationships are usually strictly species specific, but exceptions to the 'one-to-one' rule occur within the group we studied. In order to understand both the biogeographical history of the Ceratosolen species associated with Ficus of the subgenus Sycomorus and the origins of the specificity breakdown cases, we have used cytochrome b sequences to reconstruct a phylogeny of the fig wasps. The results show that the pollinators from the Malagasy region and those from continental Africa form two distinct clades, which probably diverged after the crossing of the Mozambique Channel by an ancestral population. The Oriental wasp species show strong affinities with the African species. The two species-specificity exceptions are due to different evolutionary events. The occurrence of the two West African pollinators associated with F. sur can be explained by successive speciation events of the mutualistic partner without plant radiation. In contrast, we hypothesize that C. galili shifted by horizontal transfer from an unknown, presumably extinct, Ficus species to F. sycomorus after this native Malagasy fig species colonized Africa.

  19. Review of Apanteles sensu stricto (Hymenoptera: Braconidae, Microgastrinae) from Area de Conservación Guanacaste, northwestern Costa Rica, with keys to all described species from Mesoamerica

    USDA-ARS?s Scientific Manuscript database

    More than half a million specimens of wild-caught Lepidoptera caterpillars have been reared for their parasitoids, identification, and DNA barcoding over a period of 34 years (and ongoing) from Area de Conservación de Guanacaste (ACG), northwestern Costa Rica. This provides the world’s best place-ba...

  20. Definition of Tenuipalpus sensu stricto (Acari, Tenuipalpidae), with redescription of Tenuipalpus caudatus (Dugès) and description of a new species from Costa Rica

    USDA-ARS?s Scientific Manuscript database

    We discuss the taxonomic history of the genus Tenuipalpus Donnadieu and re-describe Tenuipalpus caudatus (Dugès) (= T. palmatus Donnadieu) based on specimens from Portugal intercepted at the United States ports of entry, and references including photographic records of the neotype of T. caudatus. In...

  1. Divergence of Borrelia burgdorferi sensu lato spirochetes could be driven by the host: diversity of Borrelia strains isolated from ticks feeding on a single bird

    PubMed Central

    2014-01-01

    Background The controversy surrounding the potential impact of birds in spirochete transmission dynamics and their capacity to serve as a reservoir has existed for a long time. The majority of analyzed bird species are able to infect larval ticks with Borrelia. Dispersal of infected ticks due to bird migration is a key to the establishment of new foci of Lyme borreliosis. The dynamics of infection in birds supports the mixing of different species, the horizontal exchange of genetic information, and appearance of recombinant genotypes. Methods Four Borrelia burgdorferi sensu lato strains were cultured from Ixodes minor larvae and four strains were isolated from Ixodes minor nymphs collected from a single Carolina Wren (Thryothorus ludovicianus). A multilocus sequence analysis that included 16S rRNA, a 5S-23S intergenic spacer region, a 16S-23S internal transcribed spacer, flagellin, p66, and ospC separated 8 strains into 3 distinct groups. Additional multilocus sequence typing of 8 housekeeping genes, clpA, clpX, nifS, pepX, pyrG, recG, rplB, and uvrA was used to resolve the taxonomic status of bird-associated strains. Results Results of analysis of 14 genes confirmed that the level of divergence among strains is significantly higher than what would be expected for strains within a single species. The presence of cross-species recombination was revealed: Borrelia burgdorferi sensu stricto housekeeping gene nifS was incorporated into homologous locus of strain, previously assigned to B. americana. Conclusions Genetically diverse Borrelia strains are often found within the same tick or same vertebrate host, presenting a wide opportunity for genetic exchange. We report the cross-species recombination that led to incorporation of a housekeeping gene from the B. burgdorferi sensu stricto strain into a homologous locus of another bird-associated strain. Our results support the hypothesis that recombination maintains a majority of sequence polymorphism within Borrelia

  2. Divergence of Borrelia burgdorferi sensu lato spirochetes could be driven by the host: diversity of Borrelia strains isolated from ticks feeding on a single bird.

    PubMed

    Rudenko, Nataliia; Golovchenko, Maryna; Belfiore, Natalia M; Grubhoffer, Libor; Oliver, James H

    2014-01-02

    The controversy surrounding the potential impact of birds in spirochete transmission dynamics and their capacity to serve as a reservoir has existed for a long time. The majority of analyzed bird species are able to infect larval ticks with Borrelia. Dispersal of infected ticks due to bird migration is a key to the establishment of new foci of Lyme borreliosis. The dynamics of infection in birds supports the mixing of different species, the horizontal exchange of genetic information, and appearance of recombinant genotypes. Four Borrelia burgdorferi sensu lato strains were cultured from Ixodes minor larvae and four strains were isolated from Ixodes minor nymphs collected from a single Carolina Wren (Thryothorus ludovicianus). A multilocus sequence analysis that included 16S rRNA, a 5S-23S intergenic spacer region, a 16S-23S internal transcribed spacer, flagellin, p66, and ospC separated 8 strains into 3 distinct groups. Additional multilocus sequence typing of 8 housekeeping genes, clpA, clpX, nifS, pepX, pyrG, recG, rplB, and uvrA was used to resolve the taxonomic status of bird-associated strains. Results of analysis of 14 genes confirmed that the level of divergence among strains is significantly higher than what would be expected for strains within a single species. The presence of cross-species recombination was revealed: Borrelia burgdorferi sensu stricto housekeeping gene nifS was incorporated into homologous locus of strain, previously assigned to B. americana. Genetically diverse Borrelia strains are often found within the same tick or same vertebrate host, presenting a wide opportunity for genetic exchange. We report the cross-species recombination that led to incorporation of a housekeeping gene from the B. burgdorferi sensu stricto strain into a homologous locus of another bird-associated strain. Our results support the hypothesis that recombination maintains a majority of sequence polymorphism within Borrelia populations because of the re-assortment of

  3. The problem of exophily in Anopheles gambiae

    PubMed Central

    Gillies, M. T.

    1956-01-01

    Studies of the exophily exhibited by anophelines in a humid coastal area and in an arid inland region of Tanganyika gave very different results. In the former area, catches of A. gambiae were scanty and largely composed of unfed and gravid females, while in the latter, large numbers of mosquitos were caught outside and a great many of them were recently fed females. The differences are attributed primarily to the presence outside of large herds of cattle in the inland region and to their absence near the coast. The reports of exophily from other parts of Africa are also analysed and show that there is much variation in the behaviour of A. gambiae in different regions. Some of the variation can be explained in terms of environmental differences, particularly in the availability at night of different hosts. But some of it may be genetically determined. It is suggested that the main task in this field is twofold: firstly, to establish the existence and nature of the behaviour differences described; secondly, to study in detail the mosquitos that survive as exophilic populations in areas where systematic house-spraying is in operation. PMID:13404431

  4. Cancer in The Gambia: 1988–97

    PubMed Central

    Bah, E; Parkin, D M; Hall, A J; Jack, A D; Whittle, H

    2001-01-01

    We describe the incidence of cancer in The Gambia over a 10-year period using data collected through the Gambian National Cancer Registry. Major problems involved with cancer registration in a developing country, specifically in Africa are discussed. The data accumulated show a low overall rate of cancer incidence compared to more developed parts of the world. The overall age standardized incidence rates (ASR) were 61.0 and 55.7 per 100 000 for males and females, respectively. In males, liver cancer was most frequent, comprising 58% of cases (ASR 35.7) followed by non-Hodgkin lymphoma, 5.4% (ASR 2.4), lung 4.0%, (ASR 2.8) and prostate 3.3% (ASR 2.5) cancers. The most frequent cancers in females were cervix uteri 34.0% (ASR 18.9), liver 19.4% (ASR 11.2), breast 9.2% (ASR 5.5) and ovary 3.2% (ASR 1.6). The data indicate that cancers of the liver and cervix are the most prevalent cancers, and are likely to be due to infectious agents. It is hoped that immunization of children under 1 year against hepatitis B will drastically reduce the incidence of liver cancer in The Gambia. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11336472

  5. Odorant reception in the malaria mosquito Anopheles gambiae.

    PubMed

    Carey, Allison F; Wang, Guirong; Su, Chih-Ying; Zwiebel, Laurence J; Carlson, John R

    2010-03-04

    The mosquito Anopheles gambiae is the major vector of malaria in sub-Saharan Africa. It locates its human hosts primarily through olfaction, but little is known about the molecular basis of this process. Here we functionally characterize the Anopheles gambiae odorant receptor (AgOr) repertoire. We identify receptors that respond strongly to components of human odour and that may act in the process of human recognition. Some of these receptors are narrowly tuned, and some salient odorants elicit strong responses from only one or a few receptors, suggesting a central role for specific transmission channels in human host-seeking behaviour. This analysis of the Anopheles gambiae receptors permits a comparison with the corresponding Drosophila melanogaster odorant receptor repertoire. We find that odorants are differentially encoded by the two species in ways consistent with their ecological needs. Our analysis of the Anopheles gambiae repertoire identifies receptors that may be useful targets for controlling the transmission of malaria.

  6. Ivermectin inhibits the sporogony of Plasmodium falciparum in Anopheles gambiae

    PubMed Central

    2012-01-01

    Background When ingested in a blood meal, ivermectin has been shown to reduce the survivorship of Anopheles gambiae in the laboratory and field. Furthermore, ivermectin mass drug administrations in Senegal have been shown to reduce the proportion of Plasmodium falciparum-sporozoite-containing An. gambiae. This study addresses whether ivermectin inhibits sporogony of P. falciparum in An. gambiae. Methods Anophele gambiae s.s. G3 strain were fed two concentrations of ivermectin (LC25 and LC5) along with P. falciparum NF54 in human blood meals at staggered intervals. Mosquitoes ingested ivermectin concurrent with parasites (DPI 0), or at three (DPI 3), six (DPI 6), and nine (DPI 9) days post parasite ingestion, or three days prior (DPI −3) to parasite ingestion. Mosquitoes were dissected at seven, twelve or fourteen days post parasite ingestion and either oocyst or sporozoite prevalence was recorded. To determine if P. falciparum sporozoite-containing An. gambiae were more susceptible to ivermectin than uninfected controls, survivorship was recorded for mosquitoes which ingested P. falciparum or control blood meal on DPI 0 and then a second blood meal containing ivermectin (LC25) on DPI 14. Results Ivermectin (LC25) co-ingested (DPI 0) with parasites reduced the proportion of An. gambiae that developed oocysts (χ2 = 15.4842, P = 0.0002) and sporozoites (χ2 = 19.9643, P < 0.0001). Ivermectin (LC25) ingested DPI 6 (χ2 = 8.5103, P = 0.0044) and 9 (χ2 = 14.7998, P < 0.0001) reduced the proportion of An. gambiae that developed sporozoites but not when ingested DPI 3 (χ2 = 0.0113, P = 1). Ivermectin (LC5) co-ingested (DPI 0) with parasites did not reduce the proportion of An. gambiae that developed oocysts (χ2 = 4.2518, P = 0.0577) or sporozoites (χ2 = 2.3636, P = 0.1540), however, when ingested DPI −3 the proportion of An. gambiae that developed sporozoites was reduced (χ2 = 8.4806, P = 0.0047). Plasmodium falciparum infection significantly reduced the

  7. A new taxonomic classification for species in Gomphus sensu lato

    Treesearch

    Admir J. Giachini; Michael A. Castellano

    2011-01-01

    Taxonomy of the Gomphales has been revisited by combining morphology and molecular data (DNA sequences) to provide a natural classification for the species of Gomphus sensu lato. Results indicate Gomphus s.l. to be non-monophyletic, leading to new combinations and the placement of its species into four genera: Gomphus...

  8. Speciation history and widespread introgression in the European short-call tree frogs (Hyla arborea sensu lato, H. intermedia and H. sarda).

    PubMed

    Gvoždík, Václav; Canestrelli, Daniele; García-París, Mario; Moravec, Jiří; Nascetti, Giuseppe; Recuero, Ernesto; Teixeira, José; Kotlík, Petr

    2015-02-01

    European tree frogs (Hyla) characterized by short temporal parameters of the advertisement call form six genetically differentiated but morphologically cryptic taxa, H. arborea sensu stricto, H. orientalis and H. molleri from across Europe to western Asia (together referred to as H. arborea sensu lato), two putative taxa within H. intermedia (Northern and Southern) from the Italian Peninsula and Sicily, and H. sarda from Sardinia and Corsica. Here, we assess species limits and phylogenetic relationships within these 'short-call tree frogs' based on mitochondrial DNA and nuclear protein-coding markers. The mitochondrial and nuclear genes show partly incongruent phylogeographic patterns, which point to a complex history of gene flow across taxa, particularly in the Balkans. To test the species limits in the short-call tree frogs and to infer the species tree, we used coalescent-based approaches. The monophyly of H. arborea sensu lato is supported by the mtDNA as well as by the all-gene species tree. The Northern and Southern lineages of H. intermedia have been connected by nuclear gene flow (despite their deep mtDNA divergence) and should be treated as conspecific. On the contrary, the parapatric taxa within H. arborea sensu lato should be considered distinct species (H. arborea, H. orientalis, H. molleri) based on the coalescent analysis, although signs of hybridization were detected between them (H. arborea×H. orientalis; H. arborea×H. molleri). A mitochondrial capture upon secondary contact appears to explain the close mtDNA relationship between the geographically remote Iberian H. molleri and H. orientalis from around the Black Sea. Introgressive hybridization occurred also between the Balkan H. arborea and northern Italian H. intermedia, and between the Minor Asiatic H. orientalis and Arabian H. felix arabica (the latter belonging to a different acoustic group/clade). Our results shed light on the species limits in the European short-call tree frogs and show

  9. Borrelia miyamotoi sensu lato seroreactivity and seroprevalence in the northeastern United States.

    PubMed

    Krause, Peter J; Narasimhan, Sukanya; Wormser, Gary P; Barbour, Alan G; Platonov, Alexander E; Brancato, Janna; Lepore, Timothy; Dardick, Kenneth; Mamula, Mark; Rollend, Lindsay; Steeves, Tanner K; Diuk-Wasser, Maria; Usmani-Brown, Sahar; Williamson, Phillip; Sarksyan, Denis S; Fikrig, Erol; Fish, Durland

    2014-07-01

    Borrelia miyamotoi sensu lato, a relapsing fever Borrelia sp., is transmitted by the same ticks that transmit B. burgdorferi (the Lyme disease pathogen) and occurs in all Lyme disease-endemic areas of the United States. To determine the seroprevalence of IgG against B. miyamotoi sensu lato in the northeastern United States and assess whether serum from B. miyamotoi sensu lato-infected persons is reactive to B. burgdorferi antigens, we tested archived serum samples from area residents during 1991-2012. Of 639 samples from healthy persons, 25 were positive for B. miyamotoi sensu lato and 60 for B. burgdorferi. Samples from ≈10% of B. miyamotoi sensu lato-seropositive persons without a recent history of Lyme disease were seropositive for B. burgdorferi. Our results suggest that human B. miyamotoi sensu lato infection may be common in southern New England and that B. burgdorferi antibody testing is not an effective surrogate for detecting B. miyamotoi sensu lato infection.

  10. Long-term trends in Anopheles gambiae insecticide resistance in Côte d'Ivoire.

    PubMed

    Edi, Constant A V; Koudou, Benjamin G; Bellai, Louise; Adja, Akre M; Chouaibou, Mouhamadou; Bonfoh, Bassirou; Barry, Sarah J E; Johnson, Paul C D; Müller, Pie; Dongus, Stefan; N'Goran, Eliezer K; Ranson, Hilary; Weetman, David

    2014-11-28

    Malaria control is heavily dependent on the use of insecticides that target adult mosquito vectors via insecticide treated nets (ITNs) or indoor residual spraying (IRS). Four classes of insecticide are approved for IRS but only pyrethroids are available for ITNs. The rapid rise in insecticide resistance in African malaria vectors has raised alarms about the sustainability of existing malaria control activities. This problem might be particularly acute in Côte d'Ivoire where resistance to all four insecticide classes has recently been recorded. Here we investigate temporal trends in insecticide resistance across the ecological zones of Côte d'Ivoire to determine whether apparent pan-African patterns of increasing resistance are detectable and consistent across insecticides and areas. We combined data on insecticide resistance from a literature review, and bioassays conducted on field-caught Anopheles gambiae mosquitoes for the four WHO-approved insecticide classes for ITN/IRS. The data were then mapped using Geographical Information Systems (GIS) and the IR mapper tool to provide spatial and temporal distribution data on insecticide resistance in An. gambiae sensu lato from Côte d'Ivoire between 1993 and 2014. Bioassay mortality decreased over time for all insecticide classes, though with significant spatiotemporal variation, such that stronger declines were observed in the southern ecological zone for DDT and pyrethroids than in the central zone, but with an apparently opposite effect for the carbamate and organophosphate. Variation in relative abundance of the molecular forms, coupled with dramatic increase in kdr 1014F frequency in M forms (An. coluzzii) seems likely to be a contributory factor to these patterns. Although records of resistance across insecticide classes have become more common, the number of classes tested in studies has also increased, precluding a conclusion that multiple resistance has also increased. Our analyses attempted synthesis of 22

  11. Viral paratransgenesis in the malaria vector Anopheles gambiae.

    PubMed

    Ren, Xiaoxia; Hoiczyk, Egbert; Rasgon, Jason L

    2008-08-22

    Paratransgenesis, the genetic manipulation of insect symbiotic microorganisms, is being considered as a potential method to control vector-borne diseases such as malaria. The feasibility of paratransgenic malaria control has been hampered by the lack of candidate symbiotic microorganisms for the major vector Anopheles gambiae. In other systems, densonucleosis viruses (DNVs) are attractive agents for viral paratransgenesis because they infect important vector insects, can be genetically manipulated and are transmitted to subsequent generations. However, An. gambiae has been shown to be refractory to DNV dissemination. We discovered, cloned and characterized the first known DNV (AgDNV) capable of infection and dissemination in An. gambiae. We developed a flexible AgDNV-based expression vector to express any gene of interest in An. gambiae using a two-plasmid helper-transducer system. To demonstrate proof-of-concept of the viral paratransgenesis strategy, we used this system to transduce expression of an exogenous gene (enhanced green fluorescent protein; EGFP) in An. gambiae mosquitoes. Wild-type and EGFP-transducing AgDNV virions were highly infectious to An. gambiae larvae, disseminated to and expressed EGFP in epidemiologically relevant adult tissues such as midgut, fat body and ovaries and were transmitted to subsequent mosquito generations. These proof-of-principle data suggest that AgDNV could be used as part of a paratransgenic malaria control strategy by transduction of anti-Plasmodium peptides or insect-specific toxins in Anopheles mosquitoes. AgDNV will also be extremely valuable as an effective and easy-to-use laboratory tool for transient gene expression or RNAi in An. gambiae.

  12. Combining Technical Competence and Stakeholder Impact in Environmental Education: The Gambia All Schools Nursery Competition

    ERIC Educational Resources Information Center

    Paulete, Francisca E.; Orr, Blair

    2010-01-01

    Under the guidance of the Department of Forestry, the Regional Education Directorate, and Peace Corps/The Gambia, the Gambia All Schools Tree Nursery Competition, an environmental education program, was developed to introduce practical environmental education in The Gambia. Data for this report were collected using a rapid appraisal approach.…

  13. Combining Technical Competence and Stakeholder Impact in Environmental Education: The Gambia All Schools Nursery Competition

    ERIC Educational Resources Information Center

    Paulete, Francisca E.; Orr, Blair

    2010-01-01

    Under the guidance of the Department of Forestry, the Regional Education Directorate, and Peace Corps/The Gambia, the Gambia All Schools Tree Nursery Competition, an environmental education program, was developed to introduce practical environmental education in The Gambia. Data for this report were collected using a rapid appraisal approach.…

  14. Comparison of isolation rate of Borrelia burgdorferi sensu lato in two different culture media, MKP and BSK-H.

    PubMed

    Ružić-Sabljić, E; Maraspin, V; Cimperman, J; Strle, F; Lotrič-Furlan, S; Stupica, D; Cerar, T

    2014-07-01

    The aim of the study was to evaluate two culture media for Borrelia burgdorferi sensu lato isolation from a 5 × 2 × 2 mm skin biopsy that was dissected into two pieces and inoculated into modified Kelly-Pettenkofer (MKP) and Barbour-Stoenner-Kelly-H (BSK-H) medium. Samples were incubated at 33°C for up to 9 weeks. Borrelia species was determined by MluI-restriction of whole genome or by MseI-restriction of PCR product. We determined the proportion of isolation rate, 'slow-growers', contaminated specimens and Borrelia species in the two media. In each of the two media 235 skin specimens were cultivated. We found 90/470 (19.1%) contaminated cultures (BSK-H 67/235, 28.5%; MKP 23/235, 9.8%; p <0.0001). Borrelia growth was ascertained in 59/235 (25.1%) BSK-H and 102/235 (43.4%) MKP cultures (p <0.0001); the corresponding values for non-contaminated cultures were 59/168 (35.1%) and 102/212 (48.1%); (p 0.003). Fourteen specimens were positive only in BSK-H, 57 solely in MKP, and 43 in both culture media. Slow growth was present in 8/59 (13.6%) BSK-H and in 4/98 (4.1%) MKP positive cultures (p 0.019). Borrelia afzelii was identified in 44/51 (86.3%) BSK-H and in 88/98 (89.8%) MKP culture-positive samples; the corresponding findings for Boreelia garinii and B. burgdorferi sensu stricto were 6/51 (11.8%) and 9/98 (9.2%), and 1/51 (1.9%) and 1/98 (1.0%), for BSK-H and MKP, respectively. Comparison of MKP and BSK-H medium for Borrelia culturing from skin specimens of European patients with erythema migrans revealed the advantage of MKP over BSK-H.

  15. Behavioral Cost & Overdominance in Anopheles gambiae

    PubMed Central

    Diop, Malal M.; Moiroux, Nicolas; Chandre, Fabrice; Martin-Herrou, Hadrien; Milesi, Pascal; Boussari, Olayidé; Porciani, Angélique; Duchon, Stéphane; Labbé, Pierrick; Pennetier, Cédric

    2015-01-01

    In response to the widespread use of control strategies such as Insecticide Treated Nets (ITN), Anopheles mosquitoes have evolved various resistance mechanisms. Kdr is a mutation that provides physiological resistance to the pyrethroid insecticides family (PYR). In the present study, we investigated the effect of the Kdr mutation on the ability of female An. gambiae to locate and penetrate a 1cm-diameter hole in a piece of netting, either treated with insecticide or untreated, to reach a bait in a wind tunnel. Kdr homozygous, PYR-resistant mosquitoes were the least efficient at penetrating an untreated damaged net, with about 51% [39-63] success rate compared to 80% [70-90] and 78% [65-91] for homozygous susceptible and heterozygous respectively. This reduced efficiency, likely due to reduced host-seeking activity, as revealed by mosquito video-tracking, is evidence of a recessive behavioral cost of the mutation. Kdr heterozygous mosquitoes were the most efficient at penetrating nets treated with PYR insecticide, thus providing evidence for overdominance, the rarely-described case of heterozygote advantage conveyed by a single locus. The study also highlights the remarkable capacity of female mosquitoes, whether PYR-resistant or not, to locate holes in bed-nets. PMID:25831058

  16. RNAi Trigger Delivery into Anopheles gambiae Pupae.

    PubMed

    Regna, Kimberly; Harrison, Rachel M; Heyse, Shannon A; Chiles, Thomas C; Michel, Kristin; Muskavitch, Marc A T

    2016-03-08

    RNA interference (RNAi), a naturally occurring phenomenon in eukaryotic organisms, is an extremely valuable tool that can be utilized in the laboratory for functional genomic studies. The ability to knockdown individual genes selectively via this reverse genetic technique has allowed many researchers to rapidly uncover the biological roles of numerous genes within many organisms, by evaluation of loss-of-function phenotypes. In the major human malaria vector Anopheles gambiae, the predominant method used to reduce the function of targeted genes involves injection of double-stranded (dsRNA) into the hemocoel of the adult mosquito. While this method has been successful, gene knockdown in adults excludes the functional assessment of genes that are expressed and potentially play roles during pre-adult stages, as well as genes that are expressed in limited numbers of cells in adult mosquitoes. We describe a method for the injection of Serine Protease Inhibitor 2 (SRPN2) dsRNA during the early pupal stage and validate SRPN2 protein knockdown by observing decreased target protein levels and the formation of melanotic pseudo-tumors in SRPN2 knockdown adult mosquitoes. This evident phenotype has been described previously for adult stage knockdown of SRPN2 function, and we have recapitulated this adult phenotype by SRPN2 knockdown initiated during pupal development. When used in conjunction with a dye-labeled dsRNA solution, this technique enables easy visualization by simple light microscopy of injection quality and distribution of dsRNA in the hemocoel.

  17. Manipulating Steady Heat Conduction by Sensu-shaped Thermal Metamaterials

    PubMed Central

    Han, Tiancheng; Bai, Xue; Liu, Dan; Gao, Dongliang; Li, Baowen; Thong, John T. L.; Qiu, Cheng-Wei

    2015-01-01

    The ability to design the control of heat flow has innumerable benefits in the design of electronic systems such as thermoelectric energy harvesters, solid-state lighting, and thermal imagers, where the thermal design plays a key role in performance and device reliability. In this work, we employ one identical sensu-unit with facile natural composition to experimentally realize a new class of thermal metamaterials for controlling thermal conduction (e.g., thermal concentrator, focusing/resolving, uniform heating), only resorting to positioning and locating the same unit element of sensu-shape structure. The thermal metamaterial unit and the proper arrangement of multiple identical units are capable of transferring, redistributing and managing thermal energy in a versatile fashion. It is also shown that our sensu-shape unit elements can be used in manipulating dc currents without any change in the layout for the thermal counterpart. These could markedly enhance the capabilities in thermal sensing, thermal imaging, thermal-energy storage, thermal packaging, thermal therapy, and more domains beyond. PMID:25974383

  18. Manipulating Steady Heat Conduction by Sensu-shaped Thermal Metamaterials

    NASA Astrophysics Data System (ADS)

    Han, Tiancheng; Bai, Xue; Liu, Dan; Gao, Dongliang; Li, Baowen; Thong, John T. L.; Qiu, Cheng-Wei

    2015-05-01

    The ability to design the control of heat flow has innumerable benefits in the design of electronic systems such as thermoelectric energy harvesters, solid-state lighting, and thermal imagers, where the thermal design plays a key role in performance and device reliability. In this work, we employ one identical sensu-unit with facile natural composition to experimentally realize a new class of thermal metamaterials for controlling thermal conduction (e.g., thermal concentrator, focusing/resolving, uniform heating), only resorting to positioning and locating the same unit element of sensu-shape structure. The thermal metamaterial unit and the proper arrangement of multiple identical units are capable of transferring, redistributing and managing thermal energy in a versatile fashion. It is also shown that our sensu-shape unit elements can be used in manipulating dc currents without any change in the layout for the thermal counterpart. These could markedly enhance the capabilities in thermal sensing, thermal imaging, thermal-energy storage, thermal packaging, thermal therapy, and more domains beyond.

  19. Manipulating Steady Heat Conduction by Sensu-shaped Thermal Metamaterials.

    PubMed

    Han, Tiancheng; Bai, Xue; Liu, Dan; Gao, Dongliang; Li, Baowen; Thong, John T L; Qiu, Cheng-Wei

    2015-05-14

    The ability to design the control of heat flow has innumerable benefits in the design of electronic systems such as thermoelectric energy harvesters, solid-state lighting, and thermal imagers, where the thermal design plays a key role in performance and device reliability. In this work, we employ one identical sensu-unit with facile natural composition to experimentally realize a new class of thermal metamaterials for controlling thermal conduction (e.g., thermal concentrator, focusing/resolving, uniform heating), only resorting to positioning and locating the same unit element of sensu-shape structure. The thermal metamaterial unit and the proper arrangement of multiple identical units are capable of transferring, redistributing and managing thermal energy in a versatile fashion. It is also shown that our sensu-shape unit elements can be used in manipulating dc currents without any change in the layout for the thermal counterpart. These could markedly enhance the capabilities in thermal sensing, thermal imaging, thermal-energy storage, thermal packaging, thermal therapy, and more domains beyond.

  20. Established Population of Blacklegged Ticks with High Infection Prevalence for the Lyme Disease Bacterium, Borrelia burgdorferi Sensu Lato, on Corkscrew Island, Kenora District, Ontario.

    PubMed

    Scott, John D; Foley, Janet E; Clark, Kerry L; Anderson, John F; Durden, Lance A; Manord, Jodi M; Smith, Morgan L

    2016-01-01

    We document an established population of blacklegged ticks, Ixodes scapularis, on Corkscrew Island, Kenora District, Ontario, Canada. Primers of the outer surface protein A (OspA) gene, the flagellin (fla) gene, and the flagellin B (flaB) gene were used in the PCR assays to detect Borrelia burgdorferi sensu lato (s.l.), the Lyme disease bacterium. In all, 60 (73%) of 82 adult I. scapularis, were infected with B. burgdorferi s.l. As well, 6 (43%) of 14 unfed I. scapularis nymphs were positive for B. burgdorferi s.l. An I. scapularis larva was also collected from a deer mouse, and several unfed larvae were gathered by flagging leaf litter. Based on DNA sequencing of randomly selected Borrelia amplicons from six nymphal and adult I. scapularis ticks, primers for the flagellin (fla) and flagellin B (flaB) genes reveal the presence of B. burgdorferi sensu stricto (s.s.), a genospecies pathogenic to humans and certain domestic animals. We collected all 3 host-feeding life stages of I. scapularis in a single year, and report the northernmost established population of I. scapularis in Ontario. Corkscrew Island is hyperendemic for Lyme disease and has the highest prevalence of B. burgdorferi s.l. for any established population in Canada. Because of this very high infection prevalence, this population of I. scapularis has likely been established for decades. Of epidemiological significance, cottage owners, island visitors, outdoors enthusiasts, and medical professionals must be vigilant that B. burgdorferi s.l.-infected I. scapularis on Corkscrew Island pose a serious public health risk.

  1. Established Population of Blacklegged Ticks with High Infection Prevalence for the Lyme Disease Bacterium, Borrelia burgdorferi Sensu Lato, on Corkscrew Island, Kenora District, Ontario

    PubMed Central

    Scott, John D.; Foley, Janet E.; Clark, Kerry L.; Anderson, John F.; Durden, Lance A.; Manord, Jodi M.; Smith, Morgan L.

    2016-01-01

    We document an established population of blacklegged ticks, Ixodes scapularis, on Corkscrew Island, Kenora District, Ontario, Canada. Primers of the outer surface protein A (OspA) gene, the flagellin (fla) gene, and the flagellin B (flaB) gene were used in the PCR assays to detect Borrelia burgdorferi sensu lato (s.l.), the Lyme disease bacterium. In all, 60 (73%) of 82 adult I. scapularis, were infected with B. burgdorferi s.l. As well, 6 (43%) of 14 unfed I. scapularis nymphs were positive for B. burgdorferi s.l. An I. scapularis larva was also collected from a deer mouse, and several unfed larvae were gathered by flagging leaf litter. Based on DNA sequencing of randomly selected Borrelia amplicons from six nymphal and adult I. scapularis ticks, primers for the flagellin (fla) and flagellin B (flaB) genes reveal the presence of B. burgdorferi sensu stricto (s.s.), a genospecies pathogenic to humans and certain domestic animals. We collected all 3 host-feeding life stages of I. scapularis in a single year, and report the northernmost established population of I. scapularis in Ontario. Corkscrew Island is hyperendemic for Lyme disease and has the highest prevalence of B. burgdorferi s.l. for any established population in Canada. Because of this very high infection prevalence, this population of I. scapularis has likely been established for decades. Of epidemiological significance, cottage owners, island visitors, outdoors enthusiasts, and medical professionals must be vigilant that B. burgdorferi s.l.-infected I. scapularis on Corkscrew Island pose a serious public health risk. PMID:27877080

  2. ITS1, 5.8S and ITS2 secondary structure modelling for intra-specific differentiation among species of the Colletotrichum gloeosporioides sensu lato species complex.

    PubMed

    Rampersad, Sephra N

    2014-01-01

    The Colletotrichum gloeosporioides species complex is among the most destructive fungal plant pathogens in the world, however, identification of member species which are of quarantine importance is impacted by a number of factors that negatively affect species identification. Structural information of the rRNA marker may be considered to be a conserved marker which can be used as supplementary information for possible species identification. The difficulty in using ITS rDNA sequences for identification lies in the low level of sequence variation at the intra-specific level and the generation of artificially-induced sequence variation due to errors in polymerization of the ITS array during DNA replication. Type and query ITS sequences were subjected to sequence analyses prior to generation of predicted consensus secondary structures, including the pattern of nucleotide polymorphisms and number of indel haplotypes, GC content, and detection of artificially-induced sequence variation. Data pertaining to structure stability, the presence of conserved motifs in secondary structures and mapping of all sequences onto the consensus C. gloeosporioides sensu stricto secondary structure for ITS1, 5.8S and ITS2 markers was then carried out. Motifs that are evolutionarily conserved among eukaryotes were found for all ITS1, 5.8S and ITS2 sequences. The sequences exhibited conserved features typical of functional rRNAs. Generally, polymorphisms occurred within less conserved regions and were seen as bulges, internal and terminal loops or non-canonical G-U base-pairs within regions of the double stranded helices. Importantly, there were also taxonomic motifs and base changes that were unique to specific taxa and which may be used to support intra-specific identification of members of the C. gloeosporioides sensu lato species complex.

  3. Impact of Strain Heterogeneity on Lyme Disease Serology in Europe: Comparison of Enzyme-Linked Immunosorbent Assays Using Different Species of Borrelia burgdorferi Sensu Lato

    PubMed Central

    Hauser, Ulrike; Krahl, Heide; Peters, Helmut; Fingerle, Volker; Wilske, Bettina

    1998-01-01

    For the standardization of serological tests for Lyme borreliosis (LB) in Europe, the influence of the heterogeneity of Borrelia burgdorferi sensu lato must be assessed in detail. For this study four immunoglobulin M (IgM) and IgG enzyme-linked immunosorbent assays (ELISAs) with octyl-β-d-glucopyranoside extracts of strains PKo (Borrelia afzelii), PBi (Borrelia garinii), and PKa2 and B31 (both B. burgdorferi sensu stricto) were compared. Strains PKo, PBi, and PKa2 at the passages used for antigen preparations abundantly expressed outer surface protein C (OspC), whereas strain B31 at the passage used for antigen preparation did not express OspC. Sera (all from Germany) from 222 patients with clinically defined LB of all stages, 133 blood donors, and 458 forest workers were tested. None of the forest workers had symptoms consistent with LB at the time that the samples were collected. For IgM tests, receiver operating characteristic curves demonstrated that discrimination between sera from patients and blood donors was best with strain PKo and worst with strain B31. The discriminatory abilities of the four IgG ELISAs were similar in a diagnostically reasonable specificity range (90 to 100%). More than 20% of the sera from forest workers reacted strongly in the PKo IgG ELISA (optical density value, >1.5; other assays, less than 8%). Western blots of the sera with the most discrepant ELISA results revealed almost exclusive reactivity with p17. This highly immunogenic antigen is only expressed by strain PKo. This observation might be important for the development of assays enabling discrimination between asymptomatic or previous infection and active disease. PMID:9466753

  4. Reappraisal of Hydatigera taeniaeformis (Batsch, 1786) (Cestoda: Taeniidae) sensu lato with description of Hydatigera kamiyai n. sp.

    PubMed

    Lavikainen, Antti; Iwaki, Takashi; Haukisalmi, Voitto; Konyaev, Sergey V; Casiraghi, Maurizio; Dokuchaev, Nikolai E; Galimberti, Andrea; Halajian, Ali; Henttonen, Heikki; Ichikawa-Seki, Madoka; Itagaki, Tadashi; Krivopalov, Anton V; Meri, Seppo; Morand, Serge; Näreaho, Anu; Olsson, Gert E; Ribas, Alexis; Terefe, Yitagele; Nakao, Minoru

    2016-05-01

    The common cat tapeworm Hydatigera taeniaeformis is a complex of three morphologically cryptic entities, which can be differentiated genetically. To clarify the biogeography and the host spectrum of the cryptic lineages, 150 specimens of H. taeniaeformis in various definitive and intermediate hosts from Eurasia, Africa and Australia were identified with DNA barcoding using partial mitochondrial cytochrome c oxidase subunit 1 gene sequences and compared with previously published data. Additional phylogenetic analyses of selected isolates were performed using nuclear DNA and mitochondrial genome sequences. Based on molecular data and morphological analysis, Hydatigera kamiyai n. sp. Iwaki is proposed for a cryptic lineage, which is predominantly northern Eurasian and uses mainly arvicoline rodents (voles) and mice of the genus Apodemus as intermediate hosts. Hydatigera taeniaeformis sensu stricto (s.s.) is restricted to murine rodents (rats and mice) as intermediate hosts. It probably originates from Asia but has spread worldwide. Despite remarkable genetic divergence between H. taeniaeformis s.s. and H. kamiyai, interspecific morphological differences are evident only in dimensions of rostellar hooks. The third cryptic lineage is closely related to H. kamiyai, but its taxonomic status remains unresolved due to limited morphological, molecular, biogeographical and ecological data. This Hydatigera sp. is confined to the Mediterranean and its intermediate hosts are unknown. Further studies are needed to classify Hydatigera sp. either as a distinct species or a variant of H. kamiyai. According to previously published limited data, all three entities occur in the Americas, probably due to human-mediated introductions. Copyright © 2016 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  5. Genetic variability within Borrelia burgdorferi sensu lato genospecies established by PCR-single-strand conformation polymorphism analysis of the rrfA-rrlB intergenic spacer in ixodes ricinus ticks from the Czech Republic.

    PubMed

    Derdáková, Markéta; Beati, Lorenza; Pet'ko, Branislav; Stanko, Michal; Fish, Durland

    2003-01-01

    In Europe the Borrelia burgdorferi sensu lato complex is represented by five distinct genospecies: Borrelia burgdorferi sensu stricto, Borrelia afzelii, Borrelia garinii, Borrelia valaisiana, and Borrelia lusitaniae. These taxonomic entities are known to differ in their specific associations with vertebrate hosts and to provoke distinct clinical manifestations in human patients. However, exceptions to these rules have often been observed, indicating that strains belonging to a single genospecies may be more heterogeneous than expected. It is, therefore, important to develop alternative identification tools which are able to distinguish Borrelia strains not only at the specific level but also at the intraspecific level. DNA from a sample of 370 Ixodes ricinus ticks collected in the Czech Republic was analyzed by PCR for the presence of a approximately 230-bp fragment of the rrfA-rrlB intergenic spacer of Borrelia spp. A total of 20.5% of the ticks were found to be positive. The infecting genospecies were identified by analyzing the amplified products by the restriction fragment length polymorphism (RFLP) method with restriction enzyme MseI and by single-strand conformation polymorphism (SSCP) analysis. The two methods were compared, and PCR-SSCP analysis appeared to be a valuable tool for rapid identification of spirochetes at the intraspecific level, particularly when large samples are examined. Furthermore, by using PCR-SSCP analysis we identified a previously unknown Borrelia genotype, genotype I-77, which would have gone unnoticed if RFLP analysis alone had been used.

  6. Genetic Variability within Borrelia burgdorferi Sensu Lato Genospecies Established by PCR-Single-Strand Conformation Polymorphism Analysis of the rrfA-rrlB Intergenic Spacer in Ixodes ricinus Ticks from the Czech Republic

    PubMed Central

    Derdáková, Markéta; Beati, Lorenza; Pet'ko, Branislav; Stanko, Michal; Fish, Durland

    2003-01-01

    In Europe the Borrelia burgdorferi sensu lato complex is represented by five distinct genospecies: Borrelia burgdorferi sensu stricto, Borrelia afzelii, Borrelia garinii, Borrelia valaisiana, and Borrelia lusitaniae. These taxonomic entities are known to differ in their specific associations with vertebrate hosts and to provoke distinct clinical manifestations in human patients. However, exceptions to these rules have often been observed, indicating that strains belonging to a single genospecies may be more heterogeneous than expected. It is, therefore, important to develop alternative identification tools which are able to distinguish Borrelia strains not only at the specific level but also at the intraspecific level. DNA from a sample of 370 Ixodes ricinus ticks collected in the Czech Republic was analyzed by PCR for the presence of a ∼230-bp fragment of the rrfA-rrlB intergenic spacer of Borrelia spp. A total of 20.5% of the ticks were found to be positive. The infecting genospecies were identified by analyzing the amplified products by the restriction fragment length polymorphism (RFLP) method with restriction enzyme MseI and by single-strand conformation polymorphism (SSCP) analysis. The two methods were compared, and PCR-SSCP analysis appeared to be a valuable tool for rapid identification of spirochetes at the intraspecific level, particularly when large samples are examined. Furthermore, by using PCR-SSCP analysis we identified a previously unknown Borrelia genotype, genotype I-77, which would have gone unnoticed if RFLP analysis alone had been used. PMID:12514035

  7. Low infectivity of Plasmodium falciparum gametocytes to Anopheles gambiae following treatment with sulfadoxine–pyrimethamine in Mali

    PubMed Central

    Beavogui, Abdoul H.; Djimde, Abdoulaye A.; Gregson, Aric; Toure, Abdoulaye M.; Dao, Adama; Coulibaly, Boubacar; Ouologuem, Dinkorma; Fofana, Bakary; Sacko, Adama; Tekete, Mamadou; Kone, Aminatou; Niare, Oumou; Wele, Mamadou; Plowe, Christopher V.; Picot, Stephane; Doumbo, Ogobara K.

    2013-01-01

    Sulfadoxine–pyrimethamine (SP) treatment increases the rate of gametocyte carriage and selects SP resistance-conferring mutations in Plasmodium falciparum dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS), raising concerns of increased malaria transmission and spread of drug resistance. In a setting in Mali where SP was highly efficacious, we measured the prevalence of DHFR and DHPS mutations in P. falciparum infections with microscopy-detected gametocytes following SP treatment, and used direct feeding to assess infectivity to Anopheles gambiae sensu lato. Children and young adults presenting with uncomplicated malaria were treated with SP or chloroquine and followed for 28 days. Gametocyte carriage peaked at 67% 1 week after treatment with a single dose of SP. Those post-SP gametocytes carried significantly more DHFR and DHPS mutations than pre-treatment asexual parasites from the same population. Only 0.5% of 1728 mosquitoes fed on SP-treated gametocyte carriers developed oocysts, while 11% of 198 mosquitoes fed on chloroquine-treated gametocyte carriers were positive for oocysts. This study shows that in an area of high SP efficacy, although SP treatment sharply increased gametocyte carriage, the infectiousness of these gametocytes to the vector may be very low. Accurate and robust methods for measuring infectivity are needed to guide malaria control interventions that affect transmission. PMID:20460125

  8. Presence of susceptible wild strains of Anopheles gambiae in a large industrial palm farm located in Aboisso, South-Eastern of Côte d'Ivoire.

    PubMed

    Sadia-Kacou, Cécile M A; Alou, Ludovic P Ahoua; Edi, Ako V C; Yobo, Celine M; Adja, Maurice A; Ouattara, Allassane F; Malone, David; Koffi, Alphonsine A; Tano, Yao; Koudou, Benjamin G

    2017-04-20

    The effectiveness of malaria control programmes through implementation of vector control activities is challenged by the emergence of insecticide resistance. In the South-Eastern region of Côte d'Ivoire, where palm oil plantations remain the predominant agricultural crop, the susceptibility of wild Anopheles gambiae sensu lato species is still unknown and thus requires a particular attention. The current study was carried out to address the gap by in-depth characterization of susceptibility level of An. gambiae mosquitoes from Ehania-V1 to WHO-recommended doses of six insecticides belonging to available classes and also to screen a subset for target site mutations and possible inhibition of P450 enzymes. Overall results showed variable resistance profile across WHO-recommended insecticides tested. Mortalities ranged from 8.3% (the lowest mortality was recorded with DDT) to 98% (the highest mortality was recorded with fenitrothion). Importantly, mortality to deltamethrin, an important pyrethroid used in public health for impregnation of mosquito nets was close to 98%, precluding a possible susceptibility to this insecticide, albeit further investigations are required. Pre-exposure of An. gambiae s.l. to PBO did not show any significant variation across insecticides (p = 0.002), although a partial increase was detected for alphacypermethrin and bendiocarb, suggesting a low of activity of cytochrome P450 enzymes (p = 0.277). High frequency of kdr L1014F was recorded in both Anopheles coluzzii (91%) and in An. gambiae (96%), associated with ace-1 (R) G119S mutation at low frequency (<20%). The high mortality rate to deltamethrin, organophosphate and the non-detection of P450 activity in resistance observed in Ehania-V1 appears as a positive outcome for further control strategies as metabolic-based P450 resistance remains major challenge to manage. These results should help the National Malaria Control Programme when designing strategies for vector control in palm

  9. Girls' Familial Responsibilities and Schooling in The Gambia

    ERIC Educational Resources Information Center

    Njie, Haddy; Manion, Caroline; Badjie, Musukuta

    2015-01-01

    Like many countries in the developing world gender inequity remains a staggering problem in The Gambia, particularly at the secondary school level. In this study, we focus on the relationship between girls' education and heavy domestic workloads, herein referred to as girls' familial responsibilities. We explore this topic in relation not only to…

  10. Infertility in the Gambia: Traditional and Modern Health Care.

    ERIC Educational Resources Information Center

    Sundby, Johanne

    1997-01-01

    A population survey was undertaken to study infertility in Gambia. All infertile women in 24 randomly selected enumeration areas were assessed. Problems faced, coping mechanisms employed, and types of health care available were examined. Patterns of consultation with traditional versus formal health care and rural/urban differences were uncovered…

  11. Infertility in the Gambia: Traditional and Modern Health Care.

    ERIC Educational Resources Information Center

    Sundby, Johanne

    1997-01-01

    A population survey was undertaken to study infertility in Gambia. All infertile women in 24 randomly selected enumeration areas were assessed. Problems faced, coping mechanisms employed, and types of health care available were examined. Patterns of consultation with traditional versus formal health care and rural/urban differences were uncovered…

  12. The dance of male Anopheles gambiae in mating swarms

    USDA-ARS?s Scientific Manuscript database

    The mating behavior of the malaria vector Anopheles gambiae is of great interest from a fundamental and applied perspective. One of the most important elements of mating in this species is the crepuscular mating aggregation (swarm) composed almost entirely of males, where most coupling and inseminat...

  13. Male motion coordination in swarming Anopheles gambiae and Anopheles coluzzii

    USDA-ARS?s Scientific Manuscript database

    The Anopheles gambiae species complex comprises the primary vectors of malaria in much of sub-Saharan Africa; most of the mating in these species occurs in swarms composed almost entirely of males. Intermittent, parallel flight patterns in such swarms have been observed, but a detailed description o...

  14. Review of the genus Craspedolcus Enderlein sensu lato in China, with the description of a new genus and four new species (Hymenoptera, Braconidae, Braconinae).

    PubMed

    Li, Yang; van Achterberg, Cornelis; Chen, Xue-Xin

    2017-01-01

    A new genus is split off the genus Craspedolcus Enderlein, 1920 (Hymenoptera, Braconidae, Braconinae): Maculibracongen. n. with type species Maculibracon abruptussp. n. The genus Craspedolcus Enderlein sensu stricto is redefined, a key to both genera and to their species in China, Thailand and Vietnam is included. Craspedolcus obscuriventris Enderlein, 1920, (syn. n.) is a new synonym of Craspedolcus vagatus (Smith, 1858), as Ipobracon maculicosta Enderlein, 1920 and Iphiaulax bhotanensis Cameron, 1907 of Maculibracon simlaensis (Cameron, 1899), comb. n. The genus Craspedolcus is recorded from China for the first time with two species: Craspedolcus fraternus Enderlein, 1920, and Craspedolcus politussp. n. The genus Maculibracon is represented by three species in China: Maculibracon simlaensis (Cameron, 1899), comb. n. (also present in Vietnam), Maculibracon heisp. n. and Maculibracon luteonervissp. n. and a fourth species is described from Thailand: Maculibracon abruptussp. n.Hybogaster zebripterae Wang & Chen, 2008, from China (Fujian) is transferred to Iphiaulax Foerster, 1863, (comb. n.) and the following names are new combinations in Maculibracongen. n.: Bracon lepcha Cameron, 1899; Bracon phaedo Cameron, 1899; Bracon simlaensis Cameron, 1899; Iphiaulax bhotanensis Cameron, 1907; Iphiaulax laertius Cameron, 1903; Iphiaulax leptopterus Cameron, 1903; Iphiaulax lineaticarinatus Cameron, 1907; Ipobracon lissotomus Roman, 1914; Ipobracon maculicosta Enderlein, 1920 and Iphiaulax pallidicornis Roman, 1914. Craspedolcus montezuma (Cameron, 1887) is provisionally transferred to the genus Digonogastra Viereck, 1912.

  15. Review of the genus Craspedolcus Enderlein sensu lato in China, with the description of a new genus and four new species (Hymenoptera, Braconidae, Braconinae)

    PubMed Central

    Li, Yang; van Achterberg, Cornelis; Chen, Xue-xin

    2017-01-01

    Abstract A new genus is split off the genus Craspedolcus Enderlein, 1920 (Hymenoptera, Braconidae, Braconinae): Maculibracon gen. n. with type species Maculibracon abruptus sp. n. The genus Craspedolcus Enderlein sensu stricto is redefined, a key to both genera and to their species in China, Thailand and Vietnam is included. Craspedolcus obscuriventris Enderlein, 1920, (syn. n.) is a new synonym of Craspedolcus vagatus (Smith, 1858), as Ipobracon maculicosta Enderlein, 1920 and Iphiaulax bhotanensis Cameron, 1907 of Maculibracon simlaensis (Cameron, 1899), comb. n. The genus Craspedolcus is recorded from China for the first time with two species: Craspedolcus fraternus Enderlein, 1920, and Craspedolcus politus sp. n. The genus Maculibracon is represented by three species in China: Maculibracon simlaensis (Cameron, 1899), comb. n. (also present in Vietnam), Maculibracon hei sp. n. and Maculibracon luteonervis sp. n. and a fourth species is described from Thailand: Maculibracon abruptus sp. n. Hybogaster zebripterae Wang & Chen, 2008, from China (Fujian) is transferred to Iphiaulax Foerster, 1863, (comb. n.) and the following names are new combinations in Maculibracon gen. n.: Bracon lepcha Cameron, 1899; Bracon phaedo Cameron, 1899; Bracon simlaensis Cameron, 1899; Iphiaulax bhotanensis Cameron, 1907; Iphiaulax laertius Cameron, 1903; Iphiaulax leptopterus Cameron, 1903; Iphiaulax lineaticarinatus Cameron, 1907; Ipobracon lissotomus Roman, 1914; Ipobracon maculicosta Enderlein, 1920 and Iphiaulax pallidicornis Roman, 1914. Craspedolcus montezuma (Cameron, 1887) is provisionally transferred to the genus Digonogastra Viereck, 1912. PMID:28325963

  16. Molecular epidemiology of Haemophilus influenzae type b in the Gambia.

    PubMed Central

    Bijlmer, H A; van Alphen, L; Geelen-van den Broek, L; Greenwood, B M; Valkenburg, H A; Dankert, J

    1992-01-01

    One hundred two invasive and 64 noninvasive isolates of Haemophilus influenzae were collected in the course of a 2-year prospective field study on the epidemiology of H. influenzae meningitis in The Gambia. The isolates were serotyped, biotyped, and subtyped by outer membrane protein (OMP) profile analysis (OMP subtyping). H. influenzae meningitis was found to be caused by serotype b (95%). In invasive disease, serotype a, although present in the throat of healthy children, caused only occasionally (5.9%) disease. The distribution of biotypes of H. influenzae appeared to be very similar to that found outside The Gambia. A distinct pattern of OMP subtypes, different from other parts of the world, is prevalent in H. influenzae type b (Hib) in The Gambia. OMP subtypes 2, 4, 5, 8, and 9 were observed to be predominant. These subtypes, except subtype 2, have not been described. L subtypes (subtypes 2, 4, and 8) were associated with invasive disease, whereas non-L subtypes (subtypes 5 and 9) were found more often in healthy carriers (P less than 0.001). A significant difference in geographical distribution was found in subtypes of noninvasive Hib strains (P less than 0.05). We conclude that in The Gambia H. influenzae invasive disease is caused mainly by type b strains with a limited number of OMP subtypes, which are different from the subtypes found elsewhere in the world. These data are important for the surveillance of Hib disease in developing countries and are baseline data for a Hib polyribosyl-ribitolphosphate-conjugated vaccine trial in The Gambia. Alternative Hib OMP vaccines should include a set of representative OMPs. Images PMID:1537907

  17. Breakpoint structure of the Anopheles gambiae 2Rb chromosomal inversion

    PubMed Central

    2010-01-01

    Background Alternative arrangements of chromosome 2 inversions in Anopheles gambiae are important sources of population structure, and are associated with adaptation to environmental heterogeneity. The forces responsible for their origin and maintenance are incompletely understood. Molecular characterization of inversion breakpoints provides insight into how they arose, and provides the basis for development of molecular karyotyping methods useful in future studies. Methods Sequence comparison of regions near the cytological breakpoints of 2Rb allowed the molecular delineation of breakpoint boundaries. Comparisons were made between the standard 2R+b arrangement in the An. gambiae PEST reference genome and the inverted 2Rb arrangements in the An. gambiae M and S genome assemblies. Sequence differences between alternative 2Rb arrangements were exploited in the design of a PCR diagnostic assay, which was evaluated against the known chromosomal banding pattern of laboratory colonies and field-collected samples from Mali and Cameroon. Results The breakpoints of the 7.55 Mb 2Rb inversion are flanked by extensive runs of the same short (72 bp) tandemly organized sequence, which was likely responsible for chromosomal breakage and rearrangement. Application of the molecular diagnostic assay suggested that 2Rb has a single common origin in An. gambiae and its sibling species, Anopheles arabiensis, and also that the standard arrangement (2R+b) may have arisen twice through breakpoint reuse. The molecular diagnostic was reliable when applied to laboratory colonies, but its accuracy was lower in natural populations. Conclusions The complex repetitive sequence flanking the 2Rb breakpoint region may be prone to structural and sequence-level instability. The 2Rb molecular diagnostic has immediate application in studies based on laboratory colonies, but its usefulness in natural populations awaits development of complementary molecular tools. PMID:20974007

  18. Coxiella burnetii Seroprevalence in Small Ruminants in The Gambia

    PubMed Central

    Klaasen, Marieke; Roest, Hendrik-Jan; van der Hoek, Wim; Goossens, Bart; Secka, Arss; Stegeman, Arjan

    2014-01-01

    Background Q fever is a zoonosis caused by Coxiella burnetii, a Gram negative bacterium present worldwide. Small ruminants are considered the main reservoirs for infection of humans. This study aimed to estimate the extent of C. burnetii infection among sheep and goats in part of The Gambia. Methodology/Principal Findings This survey was carried out from March to May 2012 at two areas in The Gambia. The first area comprised a cluster of seven rural villages situated 5–15 km west of Farafenni as well as the local abattoir. A second sampling was done at the central abattoir in Abuko (30 km from the capital, Banjul) in the Western Region. Serum samples were obtained from 490 goats and 398 sheep. In addition, 67 milk samples were obtained from lactating dams. Sera were tested with a Q fever ELISA kit. C. burnetii DNA was extracted from milk samples and then detected using a specific quantitative multiplex PCR assay, targeting the IS1111a element. A multivariable mixed logistic regression model was used to examine the relationship between seropositivity and explanatory variables. An overall seroprevalence of 21.6% was found. Goats had a significantly higher seroprevalence than sheep, respectively 24.2% and 18.5%. Seropositive animals were significantly older than seronegative animals. Animals from the villages had a significantly lower seroprevalence than animals from the central abattoir (15.1% versus 29.1%). C. burnetii DNA was detected in 2 out of 67 milk samples, whereas 8 samples gave a doubtful result. Conclusion/Significance A substantial C. burnetii seroprevalence in sheep and goats in The Gambia was demonstrated. People living in close proximity to small ruminants are exposed to C. burnetii. Q fever should be considered as a possible cause of acute febrile illness in humans in The Gambia. Future studies should include a simultaneous assessment of veterinary and human serology, and include aetiology of febrile illness in local clinics. PMID:24454863

  19. Vegetation dynamics of the Tanbi Wetland National Park, The Gambia

    NASA Astrophysics Data System (ADS)

    Ceesay, A.

    2016-12-01

    Changes in mangrove vegetation have been identified as an important indicator of environmental change. The mangroves of the Tanbi Wetland National Park (TWNP) connect the Atlantic coast with the estuary of the River Gambia and as such, play an invaluable role in the agriculture, tourism and fisheries sectors of The Gambia. Our research seeks to understand the long-term changes in the mangrove vegetation to strengthen the formulation of sustainable alternative livelihoods and adaptation strategies to climate change. Mangrove vegetation dynamics was assessed by remote sensing, using decadal Landsat images covering 1973 - 2012. Physicochemical parameters were analyzed during the rainy and dry seasons of The Gambia for correlation with climate data. Our findings indicate that the long-term changes in salinity (24.5 and 35.8ppt) and water temperature (27.6oC and 30.2oC) during the rainy and dry seasons respectively are retarding mangrove growth. Mangrove vegetation cover declined by 6%, while grassland increased by 56.4%. This research concludes that long-term hyper-salinity is the cause for the stunted vegetation and lack of mangrove rejuvenation. We propose that specialized replanting systems such as the use of saplings be adopted instead of the conventional use of propagules. Alternative livelihoods also need to be diversified to support coastal communities.

  20. Borrelia miyamotoi sensu lato Seroreactivity and Seroprevalence in the Northeastern United States

    PubMed Central

    Narasimhan, Sukanya; Wormser, Gary P.; Barbour, Alan G.; Platonov, Alexander E.; Brancato, Janna; Lepore, Timothy; Dardick, Kenneth; Mamula, Mark; Rollend, Lindsay; Steeves, Tanner K.; Diuk-Wasser, Maria; Usmani-Brown, Sahar; Williamson, Phillip; Sarksyan, Denis S.; Fikrig, Erol; Fish, Durland

    2014-01-01

    Borrelia miyamotoi sensu lato, a relapsing fever Borrelia sp., is transmitted by the same ticks that transmit B. burgdorferi (the Lyme disease pathogen) and occurs in all Lyme disease�?"endemic areas of the United States. To determine the seroprevalence of IgG against B. miyamotoi sensu lato in the northeastern United States and assess whether serum from B. miyamotoi sensu lato�?"infected persons is reactive to B. burgdorferi antigens, we tested archived serum samples from area residents during 1991�?"2012. Of 639 samples from healthy persons, 25 were positive for B. miyamotoi sensu lato and 60 for B. burgdorferi. Samples from �%^10% of B. miyamotoi sensu lato�?"seropositive persons without a recent history of Lyme disease were seropositive for B. burgdorferi. Our resultsA suggest thatA human B. miyamotoiA sensu latoA infection may be common in southern New England and that B. burgdorferi antibody testing is not an effective surrogate for detecting B. miyamotoi sensu lato infection. PMID:24960072

  1. Behavioural response of the malaria vector Anopheles gambiae to host plant volatiles and synthetic blends

    USDA-ARS?s Scientific Manuscript database

    Sugar feeding is critical for survival of malaria vectors and, although discriminative plant feeding previously has been shown to occur in Anopheles gambiae s.s., little is known about the cues mediating attraction to these plants. In this study, we investigated the role of olfaction in An. gambiae ...

  2. In vitro and in vivo host range of Anopheles gambiae densovirus (AgDNV).

    PubMed

    Suzuki, Yasutsugu; Barik, Tapan K; Johnson, Rebecca M; Rasgon, Jason L

    2015-07-29

    AgDNV is a powerful gene transduction tool and potential biological control agent for Anopheles mosquitoes. Using a GFP reporter virus system, we investigated AgDNV host range specificity in four arthropod cell lines (derived from An. gambiae, Aedes albopictus and Drosophila melanogaster) and six mosquito species from 3 genera (An. gambiae, An. arabiensis, An. stephensi, Ae. albopictus, Ae. aegypti and Culex tarsalis). In vitro, efficient viral invasion, replication and GFP expression was only observed in MOS55 An. gambiae cells. In vivo, high levels of GFP were observed in An. gambiae mosquitoes. Intermediate levels of GFP were observed in the closely related species An. arabiensis. Low levels of GFP were observed in An. stephensi, Ae. albopictus, Ae. aegypti and Cx. tarsalis. These results suggest that AgDNV is a specific gene transduction tool for members of the An. gambiae species complex, and could be potentially developed into a biocontrol agent with minimal off-target effects.

  3. In vitro and in vivo host range of Anopheles gambiae densovirus (AgDNV)

    PubMed Central

    Suzuki, Yasutsugu; Barik, Tapan K.; Johnson, Rebecca M.; Rasgon, Jason L.

    2015-01-01

    AgDNV is a powerful gene transduction tool and potential biological control agent for Anopheles mosquitoes. Using a GFP reporter virus system, we investigated AgDNV host range specificity in four arthropod cell lines (derived from An. gambiae, Aedes albopictus and Drosophila melanogaster) and six mosquito species from 3 genera (An. gambiae, An. arabiensis, An. stephensi, Ae. albopictus, Ae. aegypti and Culex tarsalis). In vitro, efficient viral invasion, replication and GFP expression was only observed in MOS55 An. gambiae cells. In vivo, high levels of GFP were observed in An. gambiae mosquitoes. Intermediate levels of GFP were observed in the closely related species An. arabiensis. Low levels of GFP were observed in An. stephensi, Ae. albopictus, Ae. aegypti and Cx. tarsalis. These results suggest that AgDNV is a specific gene transduction tool for members of the An. gambiae species complex, and could be potentially developed into a biocontrol agent with minimal off-target effects. PMID:26220140

  4. Identification and molecular survey of Borrelia burgdorferi sensu lato in sika deer (Cervus nippon) from Jilin Province, north-eastern China.

    PubMed

    Zhai, Bintao; Niu, Qingli; Yang, Jifei; Liu, Zhijie; Liu, Junlong; Yin, Hong; Zeng, Qiaoying

    2017-02-01

    Lyme disease caused by Borrelia burgdorferi sensu lato (s.l.) is a common disease of domestic animals and wildlife worldwide. Sika deer is first-grade state-protected wildlife animals in China and have economic consequences for humans. It is reported that sika deer may serve as an important reservoir host for several species of B. burgdorferi s.l. and may transmit these species to humans and animals. However, little is known about the presence of Borrelia pathogens in sika deer in China. In this study, the existence and prevalence of Borrelia sp. in sika deer from four regions of Jilin Province in China was assessed. Seventy-one blood samples of sika deer were collected and tested by nested-PCRs based on 16S ribosomal RNA (16S rRNA), outer surface protein A (OspA), flagenllin (fla), and 5S-23S rRNA intergenic spacer (5S-23S rRNA) genes of B. burgdorferi s.l. Six (8.45%) samples were positive for Borrelia sp. based on sequences of 4 genes. The positive samples were detected 18 for 16S rRNA, 10 for OspA, 16 for fla and 6 for 5S-23S, with the positive rates 25.35% (95% CI=3.8-35.6), 14.08% (95% CI=3.0-21.6), 22.54% (95% CI=4.3-36.9) and 8.45% (95% CI=1.7-22.9), respectively. Sequence analysis of the positive PCR products revealed that the partial 4 genes sequences in this study were all most similar to the sequences of B. garinii and B. burgdorferi sensu stricto (s.s.), no other Borrelia genospecies were found. This is the first report of Borrelia pathogens in sika deer in China. The findings in this study indicated that sika deer as potential natural host and may spread Lyme disease pathogen to animals, ticks, and even humans.

  5. Life stage-related differences in density of questing ticks and infection with Borrelia burgdorferi sensu lato within a single cohort of Ixodes pacificus (Acari: Ixodidae).

    PubMed

    Eisen, Rebecca J; Mun, Jeomhee; Eisen, Lars; Lane, Robert S

    2004-07-01

    The primary aims of this study were to quantify the density of Ixodes pacificus Cooley and Kohls nymphs and adults of the same generational cohort collected within a single year in six oak or madrone leaf litter habitats and to compare the prevalence of infection with Borrelia burgdorferi sensu lato (s.l.) in adults originating from nymphal cohorts with a low (<1%) versus high (>10%) infection prevalence. Because adult densities were very low both in and adjacent to several sites, direct comparisons of infection prevalence between nymphs and adults were possible only for two sites. Mean density in these sites decreased from 11.95/100 m2 for nymphs to 0/100 m2 for adults in leaf litter, and infection prevalence with B. burgdorferi s.l. was four-fold higher in nymphs (7.4%) versus adults (1.6%) of the same generational cohort collected in ecotones bordering the leaf litter areas. Assuming a density of adults in leaf litter of 0.04/100 m2 (mean for all six examined sites) and an infection prevalence similar to that found in adults collected from litter ecotones, the risk of encountering infected ticks in leaf litter decreased >1,000-fold from the nymphal to adult stage. Regardless of site-specific infection prevalence in the nymphal stage (n = 2 sites; 0.7 versus 14%), the infection prevalence for the adults of the same generational cohort was similarly low (1.5-1.6%). Peak densities of adult I. pacificus were 0-0.1/100 m2 in leaf litter, 0-6.5/100 m2 in ecotonal grasslands, and 2.0-39.0/100 m2 in ecotonal chaparral. Despite more intensive sampling efforts in leaf litter, the vast majority of the 282 adults collected came from grass or chaparral ecotones (98.9%, n = 279) rather than leaf litter (1.1%, n = 3). The study yielded eight B. burgdorferi s.l.-infected adults; four of these carried B. burgdorferi sensu stricto Johnson, Schmidt, Hyde, Steigerwalt, and Brenner, and the remaining four were infected with currently undescribed B. burgdorferi s.l. spirochetes. This

  6. [The Anopheles gambiae species complex and Kdr resistance gene at the periphery of Douala, Cameroon].

    PubMed

    Ntonga Akono, P; Mbouangoro, A; Mbida Mbida, A; Ndo, C; Peka Nsangou, M F; Kekeunou, S

    2017-03-16

    This study was conducted from May to June 2015 in Yassa (industrialized area) and Logbessou (non-industrialized area), two peri-urban areas of the city of Douala, Cameroon with the aim of an assessment of the spatial distribution of the gambiae complex, the determination of their resistance to insecticides and the distribution of the Kdr mutation. Mosquito larvae were collected by the dipping method and nursed to adult stage. The sensitivity of adult Anopheles gambiae s.l. populations to DDT and pyrethroids was assessed following WHO protocol. All tested mosquitoes were identified by PCR SINE. Only survivors were used to search for the Kdr mutation. In both areas, the gambiae complex included An. coluzzii and An. gambiae sympatric in their breeding sites. However, An. gambiae was predominant in Logbessou (88%) and An. coluzzii in Yassa (68%). Tests with deltamethrin, permethrin and DDT revealed mortality rates below 90% regardless of the area of origin of the mosquitoes. PCR diagnosis of Kdr mutation showed that over 95% of survivors harbored the Kdr gene in both sites, with resistant allele frequencies ranging from 0.96 to 1.0 in An. gambiae and from 0.89 to 0.96 in An. coluzzii. The strong resistance of An. coluzzii and This study was conducted from May to June 2015 in Yassa (industrialized area) and Logbessou (nonindustrialized area), two peri-urban areas of the city of Douala, Cameroon with the aim of an assessment of the spatial distribution of the gambiae complex, the determination of their resistance to insecticides and the distribution of the Kdr mutation. Mosquito larvae were collected by the dipping method and nursed to adult stage. The sensitivity of adult Anopheles gambiae s.l. populations to DDT and pyrethroids was assessed following WHO protocol. All tested mosquitoes were identified by PCR SINE. Only survivors were used to search for the Kdr mutation. In both areas, the gambiae complex included An. coluzzii and An. gambiae sympatric in their breeding

  7. Phylogenetic Analysis of Petunia sensu Jussieu (Solanaceae) using Chloroplast DNA RFLP

    PubMed Central

    ANDO, TOSHIO; KOKUBUN, HISASHI; WATANABE, HITOSHI; TANAKA, NORIO; YUKAWA, TOMOHISA; HASHIMOTO, GORO; MARCHESI, EDUARDO; SUÁREZ, ENRIQUE; BASUALDO, ISABEL L.

    2005-01-01

    • Background and Aims The phylogenetic relationships of Petunia sensu Jussieu (Petunia sensu Wijsman plus Calibrachoa) are unclear. This study aimed to resolve this uncertainty using molecular evidence. • Methods Phylogenetic trees of 52 taxa of Petunia sensu Jussieu were constructed using restriction fragment length polymorphism (RFLP) of chloroplast DNA digested with 19 restriction enzymes and hybridized with 12 cloned Nicotiana chloroplast DNA fragments as probes. • Key Results In all, 89 phylogenetically informative RFLPs were detected and one 50 % majority consensus tree was obtained, using the maximum parsimony method, and one distance matrix tree, using the neighbour joining method. Petunia sensu Wijsman and Calibrachoa were monophyletic sister clades in both trees. Calibrachoa parviflora and C. pygmaea, previously thought to differ from the other species in terms of their cross-compatibility, seed morphology, and nuclear DNA content, formed a basal clade that was sister to the remainder of Calibrachoa. Several clades found in the phylogenetic trees corresponded to their distribution ranges, suggesting that recent speciation in the genus Petunia sensu Jussieu occurred independently in several different regions. • Conclusions The separation of Petunia sensu Wijsman and Calibrachoa was supported by chloroplast DNA analysis. Two groups in the Calibrachoa were also recognized with a high degree of confidence. PMID:15944177

  8. The Gambia and Bangladesh: the seasons and diarrhoea.

    PubMed

    Rowland, M G

    1986-09-01

    Climactic factors in the Gambia and Bangladesh have an important impact on the incidence of diarrheal disease. Both countries share some common characteristics in climate, including a cool dry winter of 3 months followed by a hot dry spring and hot wet summers of 5-7 months in length. The main difference is in the amount of rainfall. The Gambia may have 20-30 inches of rain each year; Bangladesh usually has up to 4-5 times this amount. In the Gambia, drought is a recurring problem; floods is the problem in Bangladesh. A study in the Gambia found a close link between the time of the annual peak in diarrhea in young children and the summer rains. A 2nd peak of diarrhea in the winter also was significant and was shown to coincide with a short period of intense transmission of rotavirus. Of the enteric infections of childhood, the enterotoxigenic "Escherichia coli" (ETEC), that is those producing heat-stable toxin (ST) were found to be the most important etiological agents of diarrhea in both countries, with a peak during the rains. In rural Gambia, water is obtained almost exclusively from surface wells, 15-20 meters deep. It was found that, although this water was fecally contaminated throughout the year, levels of contamination increased by up to 100 times with 1-2 days of the start of the rains because excreta is washed into the wells. It also was clear that contaminated water and domestic environment contribute to contamination of children's food. The high level of contamination of food during the summer coincided with the time of high diarrhea prevalence. In Bangladesh it was shown that the incidence of ETEC diarrhea in infants was positively correlated with the frequency of consumption of weaning foods contaminated with fecal coliforms. The seasonal peak of ETEC diarrhea coincided with the time when food was most contaminated due to higher bacterial growth caused by high temperatures. Cholera is endemic in many areas of Bangladesh but not in the Gambia. Though

  9. Dry season reproductive depression of Anopheles gambiae in the Sahel

    PubMed Central

    Yaro, Alpha S.; Traoré, Adama; Huestis, Diana L.; Adamou, Abdoulaye; Timbiné, Seydou; Kassogué, Yaya; Diallo, Moussa; Dao, Adama; Traoré, Sékou F.; Lehmann, Tovi

    2016-01-01

    The African malaria mosquito, Anopheles gambiae, is widespread south of the Sahara including in dry savannahs and semi-arid environments where no surface water exists for several months a year. Adults of the M form of An. gambiae persist through the long dry season, when no surface waters are available, by increasing their maximal survival from 4 weeks to 7 months. Dry season diapause (aestivation) presumably underlies this extended survival. Diapause in adult insects is intrinsically linked to depressed reproduction. To determine if reproduction of the Sahelian M form is depressed during the dry season, we assessed seasonal changes in oviposition, egg batch size, and egg development, as well as insemination rate and blood feeding in wild caught mosquitoes. Results from xeric Sahelian and riparian populations were compared. Oviposition response in the Sahelian M form dropped from 70% during the wet season to 20% during the dry season while the mean egg batch size among those that laid eggs fell from 173 to 101. Correspondingly, the fraction of females that exhibited gonotrophic dissociation increased over the dry season from 5% to 45%, while a similar fraction of the population retained developed eggs despite having access to water. This depression in reproduction the Sahelian M form was not caused by a reduced insemination rate. Seasonal variation in these reproductive parameters of the riparian M form population was less extreme and the duration of reproductive depression was shorter. Blood feeding responses did not change with the season in either population. Depressed reproduction during the dry season in the Sahelian M form of An. gambiae provides additional evidence for aestivation and illuminates the physiological processes involved. The differences between the Sahelian and riparian population suggest an adaptive cline in aestivation phenotypes between populations only 130 km apart. PMID:22609421

  10. Dieldrin resistance in the malaria vector Anopheles gambiae in Ghana.

    PubMed

    Brooke, B D; Hunt, R H; Matambo, T S; Koekemoer, L L; Van Wyk, P; Coetzee, M

    2006-09-01

    Anopheles gambiae Giles s.s. (Diptera: Culicidae) is one of the principal vectors of malaria in the Ashanti region of central Ghana. High levels of resistance to dieldrin were recorded in a wild-caught sample from Obuasi (south of Kumasi) as well as a laboratory colony established using material from the wild population. Cytogenetic analysis of wild-caught and laboratory samples revealed chromosomal polymorphism for inversions 2La and 2Rb. Although inversion 2La has previously been shown to be associated with dieldrin resistance in certain other laboratory strains originating from West Africa, there was no obvious association between inversion karyotype assortment and the resistance phenotype in the Obuasi population. In addition, polymerase chain reaction analysis indicated the presence of the alanine296 to glycine mutation in the GABA (gamma amino-butyric acid) receptor (which has been mapped to a chromosomal position within inversion 2La). This mutation has previously been shown to be associated with dieldrin resistance in the same An. gambiae laboratory strains of West African origin. Our data show only a weak association between the dieldrin resistance phenotype and the presence of this mutation, suggesting that another dieldrin resistance mechanism is operational in the Obuasi population. Biochemical and synergist exposure assays suggest a metabolic component, probably mediated by monooxygenase P450 enzymes. We conclude that dieldrin resistance in the An. gambiae population of the Obuasi region occurs at a high level - most likely in the absence of selection - and that control of the resistance phenotype is polyfactorial and must include components other than mutations in the GABA receptor locus.

  11. Microbial larvicides for malaria control in The Gambia

    PubMed Central

    Majambere, Silas; Lindsay, Steven W; Green, Clare; Kandeh, Balla; Fillinger, Ulrike

    2007-01-01

    Background Mosquito larval control may prove to be an effective tool for incorporating into integrated vector management (IVM) strategies for reducing malaria transmission. Here the efficacy of microbial larvicides against Anopheles gambiae s.l. was tested in preparation for a large-scale larviciding programme in The Gambia. Methods The impact of water-dispersible (WDG) and corn granule (CG) formulations of commercial Bacillus sphaericus strain 2362 (Bs; VectoLex®) and Bacillus thuringiensis var.israelensis strain AM65-52 (Bti; VectoBac®) on larval development were tested under laboratory and field conditions to (1) identify the susceptibility of local vectors, (2) evaluate the residual effect and re-treatment intervals, (3) test the effectiveness of the microbials under operational application conditions and (4) develop a method for large-scale application. Results The major malaria vectors were highly susceptible to both microbials. The lethal concentration (LC) to kill 95% of third instar larvae of Anopheles gambiae s.s. after 24 hours was 0.023 mg/l (14.9 BsITU/l) for Bs WDG and 0.132 mg/l (396 ITU/l) for Bti WDG. In general Bs had little residual effect under field conditions even when the application rate was 200 times greater than the LC95. However, there was a residual effect up to 10 days in standardized field tests implemented during the dry season. Both microbials achieved 100% mortality of larvae 24–48 hours post-application but late instar larvae were detected 4 days after treatment. Pupae development was reduced by 94% (95% Confidence Interval = 90.8–97.5%) at weekly re-treatment intervals. Field tests showed that Bs had no residual activity against anopheline larvae. Both microbials provided complete protection when applied weekly. The basic training of personnel in identification of habitats, calibration of application equipment and active larviciding proved to be successful and achieved full coverage and control of mosquito larvae for three

  12. G Protein-Coupled Receptors in Anopheles gambiae

    NASA Astrophysics Data System (ADS)

    Hill, Catherine A.; Fox, A. Nicole; Pitts, R. Jason; Kent, Lauren B.; Tan, Perciliz L.; Chrystal, Mathew A.; Cravchik, Anibal; Collins, Frank H.; Robertson, Hugh M.; Zwiebel, Laurence J.

    2002-10-01

    We used bioinformatic approaches to identify a total of 276 G protein-coupled receptors (GPCRs) from the Anopheles gambiae genome. These include GPCRs that are likely to play roles in pathways affecting almost every aspect of the mosquito's life cycle. Seventy-nine candidate odorant receptors were characterized for tissue expression and, along with 76 putative gustatory receptors, for their molecular evolution relative to Drosophila melanogaster. Examples of lineage-specific gene expansions were observed as well as a single instance of unusually high sequence conservation.

  13. Reproductive physiology of Anopheles gambiae and Anopheles atroparvus.

    PubMed

    Fernandes, Luís; Briegel, Hans

    2005-06-01

    When exposed to a human host, Anopheles gambiae started probing 4 h post-eclosion, but 95% successfully blood-fed by 16-20 h with maximal blood volumes of 5- 10 microl per female. When fed sugar, the 95% feeding was not observed until 36-40 h post-eclosion; sugar meals appeared to interfere with blood meals. Similarly in An. atroparvus, maximum volumes were 10 microl when starved but only 6 microl when fed sugar. This species did not bite before 2 d, and 95% biting was by 4 d. Given single blood meals to water-kept An. gambiae, a threshold body size for oogenesis was detected. With wing lengths below 2.8 mm, eggs never matured, but when sugar-fed, females of all sizes matured eggs including the synthesis of maternal deposits. Although sugar feeding interfered with blood feeding, more lipid was transferred to the yolk. In water-kept An. atroparvus only 5% of the females produced eggs. When sugar-fed for 4 d, all females matured eggs, so in this species sugar feeding appeared to be essential for oogenesis. An. gambiae always took multiple blood meals, tested at any time after the first ones, leading to 120 mature eggs/female. Yolk composition was 3.9 mcal protein and 3.8 mcal lipid/oocyte when kept on water, but 2.8 meal protein and 4.3 mcal lipid/oocyte with intermittent sugar meals, thus marking a surprising flexibility in synthesis of yolk protein and lipid that strongly depends on additional carbohydrates sources. Only 80% of water-fed An. atroparvus re-fed 2 d after a first blood meal with small females taking three blood meals but they still showed reduced fecundity. Only the large water-fed females matured eggs, with blood volumes higher than 9-12 microl. When fed sugar, the blood meal input was reduced, but oogenesis was possible, whereas water-fed females required three blood meals to reach the caloric level comparable to pre-feeding sugar-fed females. Water-fedAn. gambiae could survive on daily blood meals alone, but survival was further extended by

  14. A proposal for the classification of biological weapons sensu lato.

    PubMed

    Rozsa, Lajos

    2014-12-01

    Due to historical and legislation reasons, the category of bioweapons is rather poorly defined. Authors often disagree on involving or excluding agents like hormones, psychochemicals, certain plants and animals (such as weeds or pests) or synthetic organisms. Applying a wide definition apparently threatens by eroding the regime of international legislation, while narrow definitions abandon several important issues. Therefore, I propose a category of 'biological weapons sensu lato' (BWsl) that is defined here as any tool of human aggression whose acting principle is based on disciplines of biology including particularly microbiology, epidemiology, medical biology, physiology, psychology, pharmacology and ecology, but excluding those based on inorganic agents. Synthetically produced equivalents (not necessarily exact copies) and mock weapons are also included. This definition does not involve any claim to subject all these weapons to international legislation but serves a purely scholarly purpose. BWsl may be properly categorized on the base of the magnitude of the human population potentially targeted (4 levels: individuals, towns, countries, global) and the biological nature of the weapons' intended effects (4 levels: agricultural-ecological agents, and non-pathogenic, pathogenic, or lethal agents against humans).

  15. Evolution of GOUNDRY, a cryptic subgroup of Anopheles gambiae s.l., and its impact on susceptibility to Plasmodium infection.

    PubMed

    Crawford, Jacob E; Riehle, Michelle M; Markianos, Kyriacos; Bischoff, Emmanuel; Guelbeogo, Wamdaogo M; Gneme, Awa; Sagnon, N'Fale; Vernick, Kenneth D; Nielsen, Rasmus; Lazzaro, Brian P

    2016-04-01

    The recent discovery of a previously unknown genetic subgroup of Anopheles gambiae sensu lato underscores our incomplete understanding of complexities of vector population demographics in Anopheles. This subgroup, named GOUNDRY, does not rest indoors as adults and is highly susceptible to Plasmodium infection in the laboratory. Initial description of GOUNDRY suggested it differed from other known Anopheles taxa in surprising and sometimes contradictory ways, raising a number of questions about its age, population size and relationship to known subgroups. To address these questions, we sequenced the complete genomes of 12 wild-caught GOUNDRY specimens and compared these genomes to a panel of Anopheles genomes. We show that GOUNDRY is most closely related to Anopheles coluzzii, and the timing of cladogenesis is not recent, substantially predating the advent of agriculture. We find a large region of the X chromosome that has swept to fixation in GOUNDRY within the last 100 years, which may be an inversion that serves as a partial barrier to contemporary gene flow. Interestingly, we show that GOUNDRY has a history of inbreeding that is significantly associated with susceptibility to Plasmodium infection in the laboratory. Our results illuminate the genomic evolution of one of probably several cryptic, ecologically specialized subgroups of Anopheles and provide a potent example of how vector population dynamics may complicate efforts to control or eradicate malaria. © 2016 John Wiley & Sons Ltd.

  16. Nature beats nurture: a case study of the physiological fitness of free-living and laboratory-reared male Anopheles gambiae s.l.

    PubMed

    Huho, B J; Ng'habi, K R; Killeen, G F; Nkwengulila, G; Knols, B G J; Ferguson, H M

    2007-08-01

    Laboratory experimentation forms the basis for most of our knowledge of the biology of many organisms, in particular insects. However, the accuracy with which laboratory-derived estimates of insect life history and behaviour can predict their fitness and population dynamics in the wild is rarely validated. Such comparison is especially important in cases where laboratory-derived information is used to formulate and implement strategies for the genetic control of insects in nature. We have conducted a comparative study of the reproductive potential and life history of male Anopheles gambiae Gilies sensu lato mosquitoes from both standardized laboratory conditions and from natural field settings. We measured three indirect indicators of male mosquito fitness: energetic reserves, body size and survival, in a bid to determine whether the demographics and energetic limitations of wild males can be correctly predicted from their laboratory counterparts. Crucially, the body size and lipid reserves of wild males were substantially greater than those reared under standard laboratory conditions. We caution that the energetic limitations of insects as identified in the laboratory may underestimate their resilience in the wild, and discuss the implications of this phenomenon with respect to vector-borne disease control programmes based on genetic control of mosquitoes.

  17. Anopheles gambiae Antiviral Immune Response to Systemic O'nyong-nyong Infection

    PubMed Central

    Waldock, Joanna; Olson, Kenneth E.; Christophides, George K.

    2012-01-01

    Background Mosquito-borne viral diseases cause significant burden in much of the developing world. Although host-virus interactions have been studied extensively in the vertebrate host, little is known about mosquito responses to viral infection. In contrast to mosquitoes of the Aedes and Culex genera, Anopheles gambiae, the principal vector of human malaria, naturally transmits very few arboviruses, the most important of which is O'nyong-nyong virus (ONNV). Here we have investigated the A. gambiae immune response to systemic ONNV infection using forward and reverse genetic approaches. Methodology/Principal Findings We have used DNA microarrays to profile the transcriptional response of A. gambiae inoculated with ONNV and investigate the antiviral function of candidate genes through RNAi gene silencing assays. Our results demonstrate that A. gambiae responses to systemic viral infection involve genes covering all aspects of innate immunity including pathogen recognition, modulation of immune signalling, complement-mediated lysis/opsonisation and other immune effector mechanisms. Patterns of transcriptional regulation and co-infections of A. gambiae with ONNV and the rodent malaria parasite Plasmodium berghei suggest that hemolymph immune responses to viral infection are diverted away from melanisation. We show that four viral responsive genes encoding two putative recognition receptors, a galectin and an MD2-like receptor, and two effector lysozymes, function in limiting viral load. Conclusions/Significance This study is the first step in elucidating the antiviral mechanisms of A. gambiae mosquitoes, and has revealed interesting differences between A. gambiae and other invertebrates. Our data suggest that mechanisms employed by A. gambiae are distinct from described invertebrate antiviral immunity to date, and involve the complement-like branch of the humoral immune response, supressing the melanisation response that is prominent in anti-parasitic immunity. The

  18. Nationwide survey of bednet use in rural Gambia.

    PubMed Central

    D'Alessandro, U.; Aikins, M. K.; Langerock, P.; Bennett, S.; Greenwood, B. M.

    1994-01-01

    A nationwide survey was carried out to investigate the use of bednets in rural areas of the Gambia, particularly among children under 5 years old and among pregnant women. A stratified multistage design was used; 360 compounds in 60 villages were visited. Overall, 58% of beds had a net, with very little difference between villages with primary health care (PHC) facilities and those without (non-PHC). Bednet use was higher in the Central Region (76%) than in the Western and Eastern Regions (both 51%). It was highest among the Jola ethnic group (77%) and lowest among Sarahulis and other minority groups. Use of bednets was higher among target groups (such as infants, children under 5 years old, and pregnant women) than among the general population, and reached a level of over 90% in these groups in the Central Region. Use was associated with possession of a metal bed and a radio. Previous trials of impregnated bednets in the Gambia have been carried out in the Central Region, where bednet use is highest. The efforts of the National Impregnated Bednet Programme should therefore concentrate on the other regions and among the minority ethnic groups in order to increase bednet ownership. PMID:8062396

  19. Dosage Compensation in the African Malaria Mosquito Anopheles gambiae

    PubMed Central

    Rose, Graham; Krzywinska, Elzbieta; Kim, Jan; Revuelta, Loic; Ferretti, Luca; Krzywinski, Jaroslaw

    2016-01-01

    Dosage compensation is the fundamental process by which gene expression from the male monosomic X chromosome and from the diploid set of autosomes is equalized. Various molecular mechanisms have evolved in different organisms to achieve this task. In Drosophila, genes on the male X chromosome are upregulated to the levels of expression from the two X chromosomes in females. To test whether a similar mechanism is operating in immature stages of Anopheles mosquitoes, we analyzed global gene expression in the Anopheles gambiae fourth instar larvae and pupae using high-coverage RNA-seq data. In pupae of both sexes, the median expression ratios of X-linked to autosomal genes (X:A) were close to 1.0, and within the ranges of expression ratios between the autosomal pairs, consistent with complete compensation. Gene-by-gene comparisons of expression in males and females revealed mild female bias, likely attributable to a deficit of male-biased X-linked genes. In larvae, male to female ratios of the X chromosome expression levels were more female biased than in pupae, suggesting that compensation may not be complete. No compensation mechanism appears to operate in male germline of early pupae. Confirmation of the existence of dosage compensation in A. gambiae lays the foundation for research into the components of dosage compensation machinery in this important vector species. PMID:26782933

  20. The genome sequence of the malaria mosquito Anopheles gambiae.

    PubMed

    Holt, Robert A; Subramanian, G Mani; Halpern, Aaron; Sutton, Granger G; Charlab, Rosane; Nusskern, Deborah R; Wincker, Patrick; Clark, Andrew G; Ribeiro, José M C; Wides, Ron; Salzberg, Steven L; Loftus, Brendan; Yandell, Mark; Majoros, William H; Rusch, Douglas B; Lai, Zhongwu; Kraft, Cheryl L; Abril, Josep F; Anthouard, Veronique; Arensburger, Peter; Atkinson, Peter W; Baden, Holly; de Berardinis, Veronique; Baldwin, Danita; Benes, Vladimir; Biedler, Jim; Blass, Claudia; Bolanos, Randall; Boscus, Didier; Barnstead, Mary; Cai, Shuang; Center, Angela; Chaturverdi, Kabir; Christophides, George K; Chrystal, Mathew A; Clamp, Michele; Cravchik, Anibal; Curwen, Val; Dana, Ali; Delcher, Art; Dew, Ian; Evans, Cheryl A; Flanigan, Michael; Grundschober-Freimoser, Anne; Friedli, Lisa; Gu, Zhiping; Guan, Ping; Guigo, Roderic; Hillenmeyer, Maureen E; Hladun, Susanne L; Hogan, James R; Hong, Young S; Hoover, Jeffrey; Jaillon, Olivier; Ke, Zhaoxi; Kodira, Chinnappa; Kokoza, Elena; Koutsos, Anastasios; Letunic, Ivica; Levitsky, Alex; Liang, Yong; Lin, Jhy-Jhu; Lobo, Neil F; Lopez, John R; Malek, Joel A; McIntosh, Tina C; Meister, Stephan; Miller, Jason; Mobarry, Clark; Mongin, Emmanuel; Murphy, Sean D; O'Brochta, David A; Pfannkoch, Cynthia; Qi, Rong; Regier, Megan A; Remington, Karin; Shao, Hongguang; Sharakhova, Maria V; Sitter, Cynthia D; Shetty, Jyoti; Smith, Thomas J; Strong, Renee; Sun, Jingtao; Thomasova, Dana; Ton, Lucas Q; Topalis, Pantelis; Tu, Zhijian; Unger, Maria F; Walenz, Brian; Wang, Aihui; Wang, Jian; Wang, Mei; Wang, Xuelan; Woodford, Kerry J; Wortman, Jennifer R; Wu, Martin; Yao, Alison; Zdobnov, Evgeny M; Zhang, Hongyu; Zhao, Qi; Zhao, Shaying; Zhu, Shiaoping C; Zhimulev, Igor; Coluzzi, Mario; della Torre, Alessandra; Roth, Charles W; Louis, Christos; Kalush, Francis; Mural, Richard J; Myers, Eugene W; Adams, Mark D; Smith, Hamilton O; Broder, Samuel; Gardner, Malcolm J; Fraser, Claire M; Birney, Ewan; Bork, Peer; Brey, Paul T; Venter, J Craig; Weissenbach, Jean; Kafatos, Fotis C; Collins, Frank H; Hoffman, Stephen L

    2002-10-04

    Anopheles gambiae is the principal vector of malaria, a disease that afflicts more than 500 million people and causes more than 1 million deaths each year. Tenfold shotgun sequence coverage was obtained from the PEST strain of A. gambiae and assembled into scaffolds that span 278 million base pairs. A total of 91% of the genome was organized in 303 scaffolds; the largest scaffold was 23.1 million base pairs. There was substantial genetic variation within this strain, and the apparent existence of two haplotypes of approximately equal frequency ("dual haplotypes") in a substantial fraction of the genome likely reflects the outbred nature of the PEST strain. The sequence produced a conservative inference of more than 400,000 single-nucleotide polymorphisms that showed a markedly bimodal density distribution. Analysis of the genome sequence revealed strong evidence for about 14,000 protein-encoding transcripts. Prominent expansions in specific families of proteins likely involved in cell adhesion and immunity were noted. An expressed sequence tag analysis of genes regulated by blood feeding provided insights into the physiological adaptations of a hematophagous insect.

  1. Gene Expression-Based Biomarkers for Anopheles gambiae Age Grading

    PubMed Central

    Wang, Mei-Hui; Marinotti, Osvaldo; Zhong, Daibin; James, Anthony A.; Walker, Edward; Guda, Tom; Kweka, Eliningaya J.; Githure, John; Yan, Guiyun

    2013-01-01

    Information on population age structure of mosquitoes under natural conditions is fundamental to the understanding of vectorial capacity and crucial for assessing the impact of vector control measures on malaria transmission. Transcriptional profiling has been proposed as a method for predicting mosquito age for Aedes and Anopheles mosquitoes, however, whether this new method is adequate for natural conditions is unknown. This study tests the applicability of transcriptional profiling for age-grading of Anopheles gambiae, the most important malaria vector in Africa. The transcript abundance of two An. gambiae genes, AGAP009551 and AGAP011615, was measured during aging under laboratory and field conditions in three mosquito strains. Age-dependent monotonic changes in transcript levels were observed in all strains evaluated. These genes were validated as age-grading biomarkers using the mark, release and recapture (MRR) method. The MRR method determined a good correspondence between actual and predicted age, and thus demonstrated the value of age classifications derived from the transcriptional profiling of these two genes. The technique was used to establish the age structure of mosquito populations from two malaria-endemic areas in western Kenya. The population age structure determined by the transcriptional profiling method was consistent with that based on mosquito parity. This study demonstrates that the transcription profiling method based on two genes is valuable for age determination of natural mosquitoes, providing a new approach for determining a key life history trait of malaria vectors. PMID:23936017

  2. Transmission potential of Rickettsia felis infection by Anopheles gambiae mosquitoes

    PubMed Central

    Dieme, Constentin; Bechah, Yassina; Socolovschi, Cristina; Audoly, Gilles; Berenger, Jean-Michel; Faye, Ousmane; Raoult, Didier; Parola, Philippe

    2015-01-01

    A growing number of recent reports have implicated Rickettsia felis as a human pathogen, paralleling the increasing detection of R. felis in arthropod hosts across the globe, primarily in fleas. Here Anopheles gambiae mosquitoes, the primary malarial vectors in sub-Saharan Africa, were fed with either blood meal infected with R. felis or infected cellular media administered in membrane feeding systems. In addition, a group of mosquitoes was fed on R. felis-infected BALB/c mice. The acquisition and persistence of R. felis in mosquitoes was demonstrated by quantitative PCR detection of the bacteria up to day 15 postinfection. R. felis was detected in mosquito feces up to day 14. Furthermore, R. felis was visualized by immunofluorescence in salivary glands, in and around the gut, and in the ovaries, although no vertical transmission was observed. R. felis was also found in the cotton used for sucrose feeding after the mosquitoes were fed infected blood. Natural bites from R. felis-infected An. gambiae were able to cause transient rickettsemias in mice, indicating that this mosquito species has the potential to be a vector of R. felis infection. This is particularly important given the recent report of high prevalence of R. felis infection in patients with “fever of unknown origin” in malaria-endemic areas. PMID:26056256

  3. The Anopheles gambiae transcriptome - a turning point for malaria control.

    PubMed

    Domingos, A; Pinheiro-Silva, R; Couto, J; do Rosário, V; de la Fuente, J

    2017-04-01

    Mosquitoes are important vectors of several pathogens and thereby contribute to the spread of diseases, with social, economic and public health impacts. Amongst the approximately 450 species of Anopheles, about 60 are recognized as vectors of human malaria, the most important parasitic disease. In Africa, Anopheles gambiae is the main malaria vector mosquito. Current malaria control strategies are largely focused on drugs and vector control measures such as insecticides and bed-nets. Improvement of current, and the development of new, mosquito-targeted malaria control methods rely on a better understanding of mosquito vector biology. An organism's transcriptome is a reflection of its physiological state and transcriptomic analyses of different conditions that are relevant to mosquito vector competence can therefore yield important information. Transcriptomic analyses have contributed significant information on processes such as blood-feeding parasite-vector interaction, insecticide resistance, and tissue- and stage-specific gene regulation, thereby facilitating the path towards the development of new malaria control methods. Here, we discuss the main applications of transcriptomic analyses in An. gambiae that have led to a better understanding of mosquito vector competence.

  4. Aryl methylcarbamates: potency and selectivity towards wild-type and carbamate-insensitive (G119S) Anopheles gambiae acetylcholinesterase, and toxicity to G3 strain An. gambiae.

    PubMed

    Wong, Dawn M; Li, Jianyong; Lam, Polo C H; Hartsel, Joshua A; Mutunga, James M; Totrov, Maxim; Bloomquist, Jeffrey R; Carlier, Paul R

    2013-03-25

    New carbamates that are highly selective for inhibition of Anopheles gambiae acetylcholinesterase (AChE) over the human enzyme might be useful in continuing efforts to limit malaria transmission. In this report we assessed 34 synthesized and commercial carbamates for their selectivity to inhibit the AChEs found in carbamate-susceptible (G3) and carbamate-resistant (Akron) An. gambiae, relative to human AChE. Excellent correspondence is seen between inhibition potencies measured with carbamate-susceptible mosquito homogenate and purified recombinant wild-type (WT) An. gambiae AChE (AgAChE). Similarly, excellent correspondence is seen between inhibition potencies measured with carbamate-resistant mosquito homogenate and purified recombinant G119S AgAChE, consistent with our earlier finding that the Akron strain carries the G119S mutation. Although high (100- to 500-fold) WT An. gambiae vs human selectivity is observed for several compounds, none of the carbamates tested potently inhibits the G119S mutant enzyme. Finally, we describe a predictive model for WT An. gambiae tarsal contact toxicity of the carbamates that relies on inhibition potency, molecular volume, and polar surface area. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  5. Massive introgression drives species radiation at the range limit of Anopheles gambiae

    PubMed Central

    Vicente, José L.; Clarkson, Christopher S.; Caputo, Beniamino; Gomes, Bruno; Pombi, Marco; Sousa, Carla A.; Antao, Tiago; Dinis, João; Bottà, Giordano; Mancini, Emiliano; Petrarca, Vincenzo; Mead, Daniel; Drury, Eleanor; Stalker, James; Miles, Alistair; Kwiatkowski, Dominic P.; Donnelly, Martin J.; Rodrigues, Amabélia; Torre, Alessandra della; Weetman, David; Pinto, João

    2017-01-01

    Impacts of introgressive hybridisation may range from genomic erosion and species collapse to rapid adaptation and speciation but opportunities to study these dynamics are rare. We investigated the extent, causes and consequences of a hybrid zone between Anopheles coluzzii and Anopheles gambiae in Guinea-Bissau, where high hybridisation rates appear to be stable at least since the 1990s. Anopheles gambiae was genetically partitioned into inland and coastal subpopulations, separated by a central region dominated by A. coluzzii. Surprisingly, whole genome sequencing revealed that the coastal region harbours a hybrid form characterised by an A. gambiae-like sex chromosome and massive introgression of A. coluzzii autosomal alleles. Local selection on chromosomal inversions may play a role in this process, suggesting potential for spatiotemporal stability of the coastal hybrid form and providing resilience against introgression of medically-important loci and traits, found to be more prevalent in inland A. gambiae. PMID:28417969

  6. Anopheles gambiae exploits the treehole ecosystem in western Kenya: a new urban malaria risk?

    PubMed

    Omlin, Francois X; Carlson, John C; Ogbunugafor, C Brandon; Hassanali, Ahmed

    2007-12-01

    At six sites in western Kenya, we explored the presence of Anopheles immature stages in treeholes. An. gambiae larvae were found in 19 species, 13 of which are exotic. The most common exotic species were Delonix regia, Jacaranda mimosipholia, and Eucalyptus citrodora. In Kisumu city, longitudinal assessments of 10 Flamboyant trees showed repeated presence of An. gambiae s.s. in treeholes with water. Production of Anopheles larvae did not correlate with habitat volume but with habitat height, showing a strong but statistically insignificant negative correlation. During a dry season, eggs recovered by rinsing dry treeholes hatched into 2.5 +/- 3.06 An. gambiae and 7.9 +/- 8.2 Aedes larvae. In cage experiments, An. gambiae s.s. laid more eggs in water originating from treeholes than in distilled or lake water, implying preference for ovipositing in this habitat. Our findings indicate that treeholes represent a hitherto unrecognized habitat for malaria vectors, which needs further studies.

  7. Factors influencing infection and transmission of Anopheles gambiae densovirus (AgDNV) in mosquitoes

    PubMed Central

    2016-01-01

    Anopheles gambiae densovirus (AgDNV) is a potential microbial agent for paratransgenesis and gene transduction in An. gambiae, the major vector of human malaria in sub-Saharan Africa. Understanding the interaction between AgDNV and An. gambiae is critical for using AgDNV in a basic and applied manner for Anopheles gene manipulation. Here, we tested the effects of mosquito age, sex, blood feeding status, and potential for horizontal transmission using an enhanced green fluorescent protein (EGFP) reporter AgDNV system. Neither mosquito age at infection nor feeding regime affected viral titers. Female mosquitoes were more permissive to viral infection than males. Despite low viral titers, infected males were able to venereally transmit virus to females during mating, where the virus was localized with the transferred sperm in the spermathecae. These findings will be useful for designing AgDNV-based strategies to manipulate Anopheles gambiae. PMID:27867767

  8. Factors influencing infection and transmission of Anopheles gambiae densovirus (AgDNV) in mosquitoes.

    PubMed

    Barik, Tapan K; Suzuki, Yasutsugu; Rasgon, Jason L

    2016-01-01

    Anopheles gambiae densovirus (AgDNV) is a potential microbial agent for paratransgenesis and gene transduction in An. gambiae, the major vector of human malaria in sub-Saharan Africa. Understanding the interaction between AgDNV and An. gambiae is critical for using AgDNV in a basic and applied manner for Anopheles gene manipulation. Here, we tested the effects of mosquito age, sex, blood feeding status, and potential for horizontal transmission using an enhanced green fluorescent protein (EGFP) reporter AgDNV system. Neither mosquito age at infection nor feeding regime affected viral titers. Female mosquitoes were more permissive to viral infection than males. Despite low viral titers, infected males were able to venereally transmit virus to females during mating, where the virus was localized with the transferred sperm in the spermathecae. These findings will be useful for designing AgDNV-based strategies to manipulate Anopheles gambiae.

  9. How effective has tobacco tax increase been in the Gambia? A case study of tobacco control

    PubMed Central

    Nargis, Nigar; Manneh, Yahya; Krubally, Bakary; Jobe, Baboucarr; Ouma, Ahmed E Ogwell; Tcha-Kondor, Noureiny; Blecher, Evan H

    2016-01-01

    Objectives The objective of the present study was to evaluate how effective tobacco tax increase has been in increasing price of tobacco products and reducing tobacco consumption in the Gambia. In addition, it tests the hypothesis that tobacco tax revenue grows while tobacco consumption decreases as a result of tax and price increase. Setting The study is designed at the macroeconomic level to examine the import of tobacco products and revenue collected from tobacco taxation in a low-income setting. Participants The participants of this study are the government officials employed in the Ministry of Finance and Economic Affairs (MoFEA), the Gambia and the Gambia Revenue Authority, who are in charge of planning and implementing the tobacco tax policy in the Gambia. Interventions The study includes 2 consecutive interventions in tobacco tax policy in the Gambia. The first intervention was moving the tax base for the uniform specific excise tax on cigarettes from weight to pack of cigarettes in 2013. The second intervention involved increasing the excise and the environmental tax on tobacco products in 2014. Primary and secondary outcome measures The primary outcome measures were the cost, insurance and freight value and the price of tobacco products. The secondary outcome measures included the import of tobacco products and tobacco tax revenue. Results In 2013–2014, the Gambia MoFEA raised the specific excise rate, which increased price, reduced consumption and generated significantly more government revenue from tobacco products. This is a clear evidence of the win-win outcome of raising tobacco tax. In addition, the Gambia has set the example of harmonising tax rates between tobacco products that reduces the substitution between tobacco products. Conclusions The Gambia presents the best practice in tobacco taxation. There is need for documenting more country-specific evidence on the win-win outcome of raising tobacco tax. PMID:27566626

  10. How effective has tobacco tax increase been in the Gambia? A case study of tobacco control.

    PubMed

    Nargis, Nigar; Manneh, Yahya; Krubally, Bakary; Jobe, Baboucarr; Ouma, Ahmed E Ogwell; Tcha-Kondor, Noureiny; Blecher, Evan H

    2016-08-26

    The objective of the present study was to evaluate how effective tobacco tax increase has been in increasing price of tobacco products and reducing tobacco consumption in the Gambia. In addition, it tests the hypothesis that tobacco tax revenue grows while tobacco consumption decreases as a result of tax and price increase. The study is designed at the macroeconomic level to examine the import of tobacco products and revenue collected from tobacco taxation in a low-income setting. The participants of this study are the government officials employed in the Ministry of Finance and Economic Affairs (MoFEA), the Gambia and the Gambia Revenue Authority, who are in charge of planning and implementing the tobacco tax policy in the Gambia. The study includes 2 consecutive interventions in tobacco tax policy in the Gambia. The first intervention was moving the tax base for the uniform specific excise tax on cigarettes from weight to pack of cigarettes in 2013. The second intervention involved increasing the excise and the environmental tax on tobacco products in 2014. The primary outcome measures were the cost, insurance and freight value and the price of tobacco products. The secondary outcome measures included the import of tobacco products and tobacco tax revenue. In 2013-2014, the Gambia MoFEA raised the specific excise rate, which increased price, reduced consumption and generated significantly more government revenue from tobacco products. This is a clear evidence of the win-win outcome of raising tobacco tax. In addition, the Gambia has set the example of harmonising tax rates between tobacco products that reduces the substitution between tobacco products. The Gambia presents the best practice in tobacco taxation. There is need for documenting more country-specific evidence on the win-win outcome of raising tobacco tax. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  11. Characterisation of Yersinia Secretion Apparatus--Pathogenicity Island (Ysa-PI) of Yersinia enterocolitica 1B/O8 in Poland: an Idle Ysa is a Specific Hallmark of the Epidemic Sensu Stricto Strain.

    PubMed

    Wołkowicz, Tomasz; Zacharczuk, Katarzyna; Rokosz-Chudziak, Natalia; Rastawicki, Waldemar; Gierczyński, Rafał

    2015-01-01

    Yersinia secretion apparatus (Ysa), the chromosomal type three secretion system (T3SS) is considered to contribute to virulence of high-pathogenicity Yersina enterocolitica biovar 1B. DNA-sequence of Ysa pathogenicity island was determined for clinical isolate DM0110 of Y enterocolitica 1B/08 with origin in Poland. We found a premature stop-codon in the regulatory gene ysrR (mutation at position 269). Altered ysrR was detected in all tested 78 isolates of Y enterocolitica 1B/O8 collected from clinical samples in Poland from 2004 to 2013. Since aberrations in YsrR are considered to inactivate Ysa, our findings may suggest Ysa is not indispensable for Y enterocolitica 1B/O8 to infect humans.

  12. 'Who's who' in renal sphaerosporids (Bivalvulida: Myxozoa) from common carp, Prussian carp and goldfish--molecular identification of cryptic species, blood stages and new members of Sphaerospora sensu stricto.

    PubMed

    Holzer, Astrid Sibylle; Bartošová, P; Pecková, H; Tyml, T; Atkinson, S; Bartholomew, J; Sipos, D; Eszterbauer, E; Dyková, I

    2013-01-01

    Myxozoans are a group of diverse, spore-forming metazoan microparasites bound to aquatic environments. Sphaerospora dykovae (previously S. renicola) causes renal sphaerosporosis and acute swim bladder inflammation (SBI) in juvenile Cyprinus carpio carpio, in central Europe. A morphologically similar species with comparably low pathogenicity, S. angulata has been described from C. c. carpio, Carassius auratus auratus and Carassius gibelio. To clarify uncertainties and ambiguities in taxon identification in these hosts we decided to re-investigate differences in spore morphology using a statistical approach, in combination with SSU and LSU rDNA sequence analyses. We found that developing spores of S. angulata and S. dykovae cannot be distinguished morphologically and designed a duplex PCR assay for the cryptic species that demonstrated S. dykovae is specific to C. c. carpio, whereas S. angulata infects C. a. auratus and C. gibelio. The molecular identification of myxozoan blood stages in common carp and goldfish, which had previously been ascribed to Sphaerospora spp. showed that approximately 75% of blood stages were from non-sphaerosporid coelozoic species infecting these cyprinids and more than 10% were from an alien species, Myxobilatus gasterostei, developing in sticklebacks. We hereby report non-selective myxozoan host invasion and multi-species infections, whose role in SBI still requires clarification.

  13. Sampling Outdoor, Resting Anopheles gambiae and Other Mosquitoes (Diptera: Culicidae) in Western Kenya with Clay Pots

    PubMed Central

    Odiere, M.; Bayoh, M. N.; Gimnig, J.; Vulule, J.; Irungu, L.; Walker, E.

    2014-01-01

    Clay pots were analyzed as devices for sampling the outdoor resting fraction of Anopheles gambiae Giles (Diptera: Culicidae) and other mosquito species in a rural, western Kenya. Clay pots (Anopheles gambiae resting pots, herein AgREPOTs), outdoor pit shelters, indoor pyrethrum spray collections (PSC), and Colombian curtain exit traps were compared in collections done biweekly for nine intervals from April to June 2005 in 20 housing compounds. Of 10,517 mosquitoes sampled, 4,668 An. gambiae s.l. were sampled in total of which 63% were An. gambiae s.s. (46% female) and 37% were An. arabiensis (66% female). The clay pots were useful and practical for sampling both sexes of An. gambiae s.l. Additionally, 617 An. funestus (58% female) and 5,232 Culex spp. (males and females together) were collected. Temporal changes in abundance of An. gambiae s.l. were similarly revealed by all four sampling methods, indicating that the clay pots could be used as devices to quantify variation in mosquito population density. Dispersion patterns of the different species and sexes fit well the negative binomial distribution, indicating that the mosquitoes were aggregated in distribution. Aside from providing a useful sampling tool, the AgREPOT also may be useful as a delivery vehicle for insecticides or pathogens to males and females that enter and rest in them. PMID:17294916

  14. Sampling outdoor, resting Anopheles gambiae and other mosquitoes (Diptera: Culicidae) in western Kenya with clay pots.

    PubMed

    Odiere, M; Bayoh, M N; Gimnig, J; Vulule, J; Irungu, L; Walker, E

    2007-01-01

    Clay pots were analyzed as devices for sampling the outdoor resting fraction of Anopheles gambiae Giles (Diptera: Culicidae) and other mosquito species in a rural, western Kenya. Clay pots (Anopheles gambiae resting pots, herein AgREPOTs), outdoor pit shelters, indoor pyrethrum spray collections (PSC), and Colombian curtain exit traps were compared in collections done biweekly for nine intervals from April to June 2005 in 20 housing compounds. Of 10,517 mosquitoes sampled, 4,668 An. gambiae s.l. were sampled in total of which 63% were An. gambiae s.s. (46% female) and 37% were An. arabiensis (66% female). The clay pots were useful and practical for sampling both sexes of An. gambiae s.l. Additionally, 617 An. funestus (58% female) and 5,232 Culex spp. (males and females together) were collected. Temporal changes in abundance of An. gambiae s.l. were similarly revealed by all four sampling methods, indicating that the clay pots could be used as devices to quantify variation in mosquito population density. Dispersion patterns of the different species and sexes fit well the negative binomial distribution, indicating that the mosquitoes were aggregated in distribution. Aside from providing a useful sampling tool, the AgREPOT also may be useful as a delivery vehicle for insecticides or pathogens to males and females that enter and rest in them.

  15. Aestivation of the African Malaria Mosquito, Anopheles gambiae in the Sahel

    PubMed Central

    Lehmann, Tovi; Dao, Adama; Yaro, Alpha Seydou; Adamou, Abdoulaye; Kassogue, Yaya; Diallo, Moussa; Sékou, Traoré; Coscaron-Arias, Cecilia

    2010-01-01

    The African malaria mosquito, Anopheles gambiae, inhabits diverse environments including dry savannas, where surface waters required for larval development are absent for 4–8 months per year. Under such conditions, An. gambiae virtually disappears. Whether populations survive the long dry season by aestivation (a dormant state promoting extended longevity during the summer) or are reestablished by migrants from distant locations where larval sites persist has remained an enigma for over 60 years. Resolving this question is important, because fragile dry season populations may be more susceptible to control. Here, we show unequivocally that An. gambiae aestivates based on a demographic study and a mark release–recapture experiment spanning the period from the end of one wet season to the beginning of the next. During the dry season, An. gambiae was barely detectable in Sahelian villages of Mali. Five days after the first rain, before a new generation of adults could be produced, mosquito abundance surged 10-fold, implying that most mosquitoes were concealed locally until the rain. Four days after the first rain, a marked female An. gambiae s.s. was recaptured. Initially captured, marked, and released at the end of the previous wet season, she has survived the 7-month-long dry season. These results provide evidence that An. gambiae persists throughout the dry season by aestivation and open new questions for mosquito and parasite research. Improved malaria control by targeting aestivating mosquitoes using existing or novel strategies may be possible. PMID:20810827

  16. Infertility resulting from transgenic I-PpoI male Anopheles gambiae in large cage trials

    PubMed Central

    Klein, T A; Windbichler, N; Deredec, A; Burt, A; Benedict, M Q

    2012-01-01

    Objectives Anopheles gambiae is the primary vector of malaria in sub-Saharan Africa and is a potential target of genetic control programs. We determined the capacity of male A. gambiae created by germline transformation to introduce infertility into stable age-distribution populations. We also determined effects of the transgenes on life history. Methods Stable age-distribution populations of A. gambiae mosquitoes were established in large indoor cages. Male mosquitoes carrying an I-PpoI homing endonuclease gene were introduced at ×5 and ×10 release rates where they competed with target male mosquitoes for matings. Similar trials were conducted in small cages with an additional ×1 release level. Results Infertility was successfully introduced into all target populations. In supporting experiments, complete female infertility was observed in all strains and species of the A. gambiae complex to which transgenic males were mated. Life history experiments demonstrated that reductions in I-PpoI male vigor exist in the form of reduced adult male emergence, longevity and competitiveness. Discussion A. gambiae I-PpoI males are capable of introducing high levels of infertility in target populations in indoor cage trials. This was accomplished despite losses of vigor resulting from the HEG transgene. These results motivate further trials of sexually I-PpoI A. gambiae in outdoor cage and field trials. PMID:22595271

  17. Organization of olfactory centres in the malaria mosquito Anopheles gambiae

    PubMed Central

    Riabinina, Olena; Task, Darya; Marr, Elizabeth; Lin, Chun-Chieh; Alford, Robert; O'Brochta, David A.; Potter, Christopher J.

    2016-01-01

    Mosquitoes are vectors for multiple infectious human diseases and use a variety of sensory cues (olfactory, temperature, humidity and visual) to locate a human host. A comprehensive understanding of the circuitry underlying sensory signalling in the mosquito brain is lacking. Here we used the Q-system of binary gene expression to develop transgenic lines of Anopheles gambiae in which olfactory receptor neurons expressing the odorant receptor co-receptor (Orco) gene are labelled with GFP. These neurons project from the antennae and maxillary palps to the antennal lobe (AL) and from the labella on the proboscis to the suboesophageal zone (SEZ), suggesting integration of olfactory and gustatory signals occurs in this brain region. We present detailed anatomical maps of olfactory innervations in the AL and the SEZ, identifying glomeruli that may respond to human body odours or carbon dioxide. Our results pave the way for anatomical and functional neurogenetic studies of sensory processing in mosquitoes. PMID:27694947

  18. Bacterial associations reveal spatial population dynamics in Anopheles gambiae mosquitoes

    PubMed Central

    Buck, Moritz; Nilsson, Louise K. J.; Brunius, Carl; Dabiré, Roch K.; Hopkins, Richard; Terenius, Olle

    2016-01-01

    The intolerable burden of malaria has for too long plagued humanity and the prospect of eradicating malaria is an optimistic, but reachable, target in the 21st century. However, extensive knowledge is needed about the spatial structure of mosquito populations in order to develop effective interventions against malaria transmission. We hypothesized that the microbiota associated with a mosquito reflects acquisition of bacteria in different environments. By analyzing the whole-body bacterial flora of An. gambiae mosquitoes from Burkina Faso by 16 S amplicon sequencing, we found that the different environments gave each mosquito a specific bacterial profile. In addition, the bacterial profiles provided precise and predicting information on the spatial dynamics of the mosquito population as a whole and showed that the mosquitoes formed clear local populations within a meta-population network. We believe that using microbiotas as proxies for population structures will greatly aid improving the performance of vector interventions around the world. PMID:26960555

  19. Literacy, education and adherence to antiretroviral therapy in The Gambia.

    PubMed

    Hegazi, A; Bailey, R L; Ahadzie, B; Alabi, A; Peterson, K

    2010-11-01

    We examined the relationship of patients' literacy and education to antiretroviral therapy (ART) adherence in an urban treatment centre in The Gambia. Information on education and literacy systematically collected before ART initiation was compared against selected adherence outcomes. Formally educated patients were significantly more likely to achieve virological suppression at both six and 12 months (87% vs. 67%, OR=3.13, P=0.03; 88% vs. 63%, OR=4.49, P=0.007, respectively). Literate patients had similar benefit at 12 months (OR=3.39 P=0.03), with improved virological outcomes associated with degree of literacy (P=0.003). A trend towards similar results was seen at 6 months for Koranically educated patients; however, this was no longer apparent at 12 months. No significant correlation was seen between socio-demographic characteristics and missed appointments. Our study suggests that literacy, formal education and possibly Koranic education may impact favourably on adherence to ART.

  20. Malaria vectorial capacity of a population of Anopheles gambiae

    PubMed Central

    Garrett-Jones, C.; Shidrawi, G. R.

    1969-01-01

    In order to assess the factors of malaria vectorial capacity and the daily reproduction rate, separate consideration is given to data from Kankiya, Northern Nigeria, concerning the incidence of vector—man contact (the man-biting rate), the vector's expectation of infective life, as reflected by the proportion of parous mosquitos under certain conditions, and the vector's man-biting habit, comprising the frequency of feeding and the human blood index. The main difficulty in the assessment of each of these factors was shown to be that of representative and adequate sampling, especially in a sprayed area. In order to compensate for deficiencies in the Kankiya data, especially with regard to the daily and cyclic survival-rates, the gonotrophic cycle and the effective sporogonic period, more complete published data on an Anopheles gambiae population in East Africa were examined, and extrapolations were made from these data in spite of the consequential risks involved. The results of the analysis show that the spraying of an area with DDT reduced the malaria vectorial capacity of Anopheles gambiae sp. B (the main vector of Plasmodium falciparum in the area) by an over-all factor of about 23 times. Nevertheless the basic reproduction rate of the disease is estimated to have averaged slightly over 20 in the sprayed area during the 6 months of the main transmission season. This is consistent with an observed recovery in the parasite rate, which had been reduced to a very low level by regular mass drug administration through the preceding dry season. The analysis was a tentative exercise in “epidemiological entomology” and it is suggested that in the postgraduate teaching of tropical hygiene, the epidemiological approach to entomology should be preferred to the classical morphological-bionomical approach. PMID:5306719

  1. Emergency, anaesthetic and essential surgical capacity in the Gambia.

    PubMed

    Iddriss, Adam; Shivute, Nestor; Bickler, Stephen; Cole-Ceesay, Ramou; Jargo, Bakary; Abdullah, Fizan; Cherian, Meena

    2011-08-01

    To assess the resources for essential and emergency surgical care in the Gambia. The World Health Organization's Tool for Situation Analysis to Assess Emergency and Essential Surgical Care was distributed to health-care managers in facilities throughout the country. The survey was completed by 65 health facilities - one tertiary referral hospital, 7 district/general hospitals, 46 health centres and 11 private health facilities - and included 110 questions divided into four sections: (i) infrastructure, type of facility, population served and material resources; (ii) human resources; (iii) management of emergency and other surgical interventions; (iv) emergency equipment and supplies for resuscitation. Questionnaire data were complemented by interviews with health facility staff, Ministry of Health officials and representatives of nongovernmental organizations. Important deficits were identified in infrastructure, human resources, availability of essential supplies and ability to perform trauma, obstetric and general surgical procedures. Of the 18 facilities expected to perform surgical procedures, 50.0% had interruptions in water supply and 55.6% in electricity. Only 38.9% of facilities had a surgeon and only 16.7% had a physician anaesthetist. All facilities had limited ability to perform basic trauma and general surgical procedures. Of public facilities, 54.5% could not perform laparotomy and 58.3% could not repair a hernia. Only 25.0% of them could manage an open fracture and 41.7% could perform an emergency procedure for an obstructed airway. The present survey of health-care facilities in the Gambia suggests that major gaps exist in the physical and human resources needed to carry out basic life-saving surgical interventions.

  2. Emergency, anaesthetic and essential surgical capacity in the Gambia

    PubMed Central

    Shivute, Nestor; Bickler, Stephen; Cole-Ceesay, Ramou; Jargo, Bakary; Abdullah, Fizan; Cherian, Meena

    2011-01-01

    Abstract Objective To assess the resources for essential and emergency surgical care in the Gambia. Methods The World Health Organization’s Tool for Situation Analysis to Assess Emergency and Essential Surgical Care was distributed to health-care managers in facilities throughout the country. The survey was completed by 65 health facilities – one tertiary referral hospital, 7 district/general hospitals, 46 health centres and 11 private health facilities – and included 110 questions divided into four sections: (i) infrastructure, type of facility, population served and material resources; (ii) human resources; (iii) management of emergency and other surgical interventions; (iv) emergency equipment and supplies for resuscitation. Questionnaire data were complemented by interviews with health facility staff, Ministry of Health officials and representatives of nongovernmental organizations. Findings Important deficits were identified in infrastructure, human resources, availability of essential supplies and ability to perform trauma, obstetric and general surgical procedures. Of the 18 facilities expected to perform surgical procedures, 50.0% had interruptions in water supply and 55.6% in electricity. Only 38.9% of facilities had a surgeon and only 16.7% had a physician anaesthetist. All facilities had limited ability to perform basic trauma and general surgical procedures. Of public facilities, 54.5% could not perform laparotomy and 58.3% could not repair a hernia. Only 25.0% of them could manage an open fracture and 41.7% could perform an emergency procedure for an obstructed airway. Conclusion The present survey of health-care facilities in the Gambia suggests that major gaps exist in the physical and human resources needed to carry out basic life-saving surgical interventions. PMID:21836755

  3. An epidemiological study of RSV infection in the Gambia.

    PubMed Central

    Weber, Martin W.; Milligan, Paul; Sanneh, Mariama; Awemoyi, Agnes; Dakour, Raduwan; Schneider, Gisela; Palmer, Ayo; Jallow, Mariatou; Oparaogu, Anslem; Whittle, Hilton; Mulholland, E. Kim; Greenwood, Brian M.

    2002-01-01

    OBJECTIVE: To describe the epidemiology of respiratory syncytial virus (RSV) infection in a developing country. METHODS: The work was carried out in three hospitals for primary cases and in the community for secondary cases in the western region of the Gambia, West Africa. RSV infection was diagnosed by immunofluorescence of nasopharyngeal aspirate samples in children younger than two years admitted to hospital with acute lower respiratory infection (ALRI). Routine records of all children with ALRI were analysed, and the incidence rates of ALRI, severe RSV-associated respiratory illness and hypoxaemic RSV infections were compared. A community-based study was undertaken to identify secondary cases and to obtain information about spread of the virus. FINDINGS: 4799 children with ALRI who were younger than two years and lived in the study area were admitted to the study hospitals: 421 had severe RSV-associated respiratory illness; 55 of these were hypoxaemic. Between 1994 and 1996, the observed incidence rate for ALRI in 100 children younger than one year living close to hospital was 9.6 cases per year; for severe RSV-associated respiratory illness 0.83; and for hypoxaemic RSV-associated respiratory illness 0.089. The proportion of all ALRI admissions due to RSV was 19%. Overall, 41% of children younger than five years in compounds in which cases lived and 42% in control compounds had evidence of RSV infection during the surveillance period. CONCLUSION: RSV is an important cause of ALRI leading to hospital admission in the Gambia. Morbidity is considerable and efforts at prevention are worthwhile. PMID:12163920

  4. Infection of Ixodes ricinus (Acari: Ixodidae) by Borrelia burgdorferi sensu lato in North Africa

    USGS Publications Warehouse

    Zhioua, E.; Bouattour, A.; Hu, C.M.; Gharbi, M.; Aeschliman, A.; Ginsberg, H.S.; Gern, L.

    1999-01-01

    Free-living adult Ixodes ricinus L. were collected in Amdoun, situated in the Kroumiry mountains in northwestern Tunisia (North Africa). Using direct fluorescence antibody assay, the infection rate of field-collected I. ricinus by Borrelia burgdorferi sensu lato was 30.5% (n = 72). No difference in infection rate was observed between male and female ticks. Spirochetes that had been isolated from I. ricinus from Ain Drahim (Kroumiry Mountains) in 1988 were identified as Borrelia lusitaniae (formerly genospecies PotiB2). This is the first identification of a genospecies of Borrelia burgdorferi sensu lato from the continent of Africa.

  5. Pan-genome and phylogeny of Bacillus cereus sensu lato.

    PubMed

    Bazinet, Adam L

    2017-08-02

    Bacillus cereus sensu lato (s. l.) is an ecologically diverse bacterial group of medical and agricultural significance. In this study, I use publicly available genomes and novel bioinformatic workflows to characterize the B. cereus s. l. pan-genome and perform the largest phylogenetic and population genetic analyses of this group to date in terms of the number of genes and taxa included. With these fundamental data in hand, I identify genes associated with particular phenotypic traits (i.e., "pan-GWAS" analysis), and quantify the degree to which taxa sharing common attributes are phylogenetically clustered. A rapid k-mer based approach (Mash) was used to create reduced representations of selected Bacillus genomes, and a fast distance-based phylogenetic analysis of this data (FastME) was performed to determine which species should be included in B. cereus s. l. The complete genomes of eight B. cereus s. l. species were annotated de novo with Prokka, and these annotations were used by Roary to produce the B. cereus s. l. pan-genome. Scoary was used to associate gene presence and absence patterns with various phenotypes. The orthologous protein sequence clusters produced by Roary were filtered and used to build HaMStR databases of gene models that were used in turn to construct phylogenetic data matrices. Phylogenetic analyses used RAxML, DendroPy, ClonalFrameML, PAUP*, and SplitsTree. Bayesian model-based population genetic analysis assigned taxa to clusters using hierBAPS. The genealogical sorting index was used to quantify the phylogenetic clustering of taxa sharing common attributes. The B. cereus s. l. pan-genome currently consists of ≈60,000 genes, ≈600 of which are "core" (common to at least 99% of taxa sampled). Pan-GWAS analysis revealed genes associated with phenotypes such as isolation source, oxygen requirement, and ability to cause diseases such as anthrax or food poisoning. Extensive phylogenetic analyses using an unprecedented amount of data

  6. Efficacy of two different house screening interventions against exposure to malaria and anaemia in children in The Gambia: a randomized controlled trial

    PubMed Central

    Kirby, Matthew J; Ameh, David; Green, Clare; Jawara, Musa; Milligan, Paul J; Bottomley, Christian; Snell, Paul C; Conway, David J; Lindsay, Steve W

    2013-01-01

    Summary Background House screening should protect people against malaria. We assessed whether two types of house screening, full screening of windows, doors and closing eaves or installing netting ceilings in local houses, could reduce malaria vector house entry and anaemia in children, in an area of seasonal transmission. Methods 500 occupied houses in and near Farafenni town in The Gambia were randomly assigned to receive full screening, screened ceilings, or no screening, in an area where coverage of insecticide-treated nets was low. Screening was not treated with insecticide. Exposure to mosquitoes indoors was assessed by fortnightly light trap collections, and haemoglobin (Hb) concentration and the prevalence of anaemia and parasitaemia measured in children, aged 6 months to 10 years old, at the end of the transmission season. Findings The mean number of Anopheles gambiae sensu lato mosquitoes, the principal malaria vector, was reduced by 59% in houses with full screening (95% CI 46, 69; p<0.001) and 47% in houses with screened ceilings (95% CI 30, 60; p<0.001) compared with unscreened houses (37.5/trap/night). Anaemia prevalence (Hb <80g/L) was 19.0% among children in unscreened houses, compared to 12.3% with full screening, adjusted odds ratio (OR) 0.53 (0.29, 0.97; p=0.04), and 11.7% with screened ceilings, adjusted OR 0.51, (0.27, 0.96; p=0.04). Mean Hb concentration was higher in children living in fully screened houses and in houses with screened ceilings (104g/L in both groups), than those in unscreened houses (100g/L); adjusted estimates of the differences 3.7g/L (0.3, 7.2; p=0.03) and 4.2g/L (0.6, 7.7; p=0.02) respectively. There was no evidence of an effect on the prevalence of malaria infection. Interpretation House screening substantially reduced the number of mosquitoes inside houses and can contribute to prevention of anaemia in children. Funding Medical Research Council PMID:19732949

  7. Does insecticide resistance contribute to heterogeneities in malaria transmission in The Gambia?

    PubMed

    Opondo, Kevin Ochieng'; Weetman, David; Jawara, Musa; Diatta, Mathurin; Fofana, Amfaal; Crombe, Florence; Mwesigwa, Julia; D'Alessandro, Umberto; Donnelly, Martin James

    2016-03-15

    Malaria hotspots, areas with consistently higher than average transmission, may become increasingly common as malaria declines. This phenomenon, currently observed in The Gambia, may be caused by several factors, including some related to the local vectors, whose contribution is poorly understood. Using WHO susceptibility bioassays, insecticide resistance status was determined in vector populations sampled from six pairs of villages across The Gambia, each pair contained a low and high prevalence village. Three vector species were observed (23.5% Anopheles arabiensis, 31.2% Anopheles gambiae, 43.3% Anopheles coluzzii and 2.0% An. coluzzii × An. gambiae hybrids). Even at a fine scale, significant differences in species composition were detected within village pairs. Resistance to both DDT and deltamethrin was more common in An. gambiae, most markedly in the eastern part of The Gambia and partly attributable to differing frequencies of resistance mutations. The Vgsc-1014F target site mutation was strongly associated with both DDT (OR = 256.7, (95% CI 48.6-6374.3, p < 0.001) and deltamethrin survival (OR = 9.14, (95% CI 4.24-21.4, p < 0.001). A second target site mutation, Vgsc-1575Y, which co-occurs with Vgsc-1014F, and a metabolic marker of resistance, Gste2-114T, conferred additional survival benefits to both insecticides. DDT resistance occurred significantly more frequently in villages with high malaria prevalence (p = 0.025) though this did not apply to deltamethrin resistance. Whilst causality of relationships requires further investigation, variation in vector species and insecticide resistance in The Gambia is associated with malaria endemicity; with a notably higher prevalence of infection and insecticide resistance in the east of the country. In areas with heterogeneous malaria transmission, the role of the vector should be investigated to guide malaria control interventions.

  8. First documentation of ivermectin resistance in Rhipicephalus sanguineus sensu lato (Acari: Ixodidae)

    USDA-ARS?s Scientific Manuscript database

    The brown dog tick, Rhipicephalus sanguineus sensu lato (Latreille, 1806), is an ectoparasite and disease vector of significant veterinary and public health importance that is distributed widely around the world. The indiscriminate use of chemicals for tick control exerts a strong selective pressure...

  9. A new species of Chaenusa Haliday sensu lato (Hymenoptera: Braconidae) from the Nearctic Region

    USDA-ARS?s Scientific Manuscript database

    Chaenusa psillosae Kula, new species from the Nearctic Region is described. Specimens upon which the new species is described were reared from an undetermined species of Hydrellia Robineau-Desvoidy infesting Sagittaria latifolia Willd. A key to the New World species of Chaenusa sensu lato is amended...

  10. Habitat-Specific Diversity of Borrelia burgdorferi Sensu Lato in Europe, Exemplified by Data from Latvia

    PubMed Central

    Etti, Susanne; Hails, Rosie; Schäfer, Stefanie M.; De Michelis, Simona; Sewell, Henna-Sisko; Bormane, Antra; Donaghy, Michael; Kurtenbach, Klaus

    2003-01-01

    The distribution of Borrelia burgdorferi sensu lato genospecies in questing Ixodes ricinus ticks from ecologically distinct habitats in Latvia was analyzed. A significant variation in the frequency of the genospecies across sites was observed, pointing to the importance of the host community in the ecology of Lyme borreliosis. PMID:12732580

  11. Multilocus sequence typing of Pseudomonas syringae sensu lato confirms previously described genomospecies and permits rapid identification.

    USDA-ARS?s Scientific Manuscript database

    Since 2002, severe leaf spotting on parsley (Petroselinum crispum L.) has occurred in Monterey County, California. One of two different pathovars of Pseudomonas syringae sensu lato were isolated from diseased leaves from seven distinct outbreaks and twice from the same outbreak (2002 and 2009). Frag...

  12. In vitro repellency of DEET against the ticks Rhipicephalus sanguineus sensu lato and Amblyomma sculptum

    USDA-ARS?s Scientific Manuscript database

    Rhipicephalus sanguineus sensu lato and Amblyomma sculptum can parasite humans and domestic animals and are vectors of pathogens, including zoonoses. Repellents are an important tool of tick control. This study aimed to compare the efficacy of N,N-diethyl- 3-methylbenzamide (DEET), a standard repell...

  13. Aryl methylcarbamates: potency and selectivity towards wild-type and carbamate-insensitive (G119S) Anopheles gambiae acetylcholinesterase, and toxicity to G3 Strain An. gambiae

    PubMed Central

    Wong, Dawn M.; Li, Jianyong; Lam, Polo C.H.; Hartsel, Joshua A.; Mutunga, James M.; Totrov, Maxim; Bloomquist, Jeffrey R.; Carlier, Paul R.

    2012-01-01

    New carbamates that are highly selective for inhibition of Anopheles gambiae acetylcholinesterase (AChE) over the human enzyme might be useful in continuing efforts to limit malaria transmission. In this report we assessed 34 synthesized and commercial carbamates for their selectivity to inhibit the AChEs found in carbamate-susceptible (G3) and carbamate-resistant (Akron) An. gambiaerelative to human AChE. Excellent correspondence is seen between inhibition potencies measured with carbamate-susceptible mosquito homogenate and purified recombinant wild-type (WT) An. gambiae AChE (AgAChE). Similarly, excellent correspondence is seen between inhibition potencies measured with carbamate-resistant mosquito homogenate and purified recombinant G119S AgAChE, consistent with our earlier finding that the Akron strain carries the G119S mutation. Although high (100- to 500-fold) WT An. gambiae vs human selectivity is observed for several compounds, none of the carbamates tested potently inhibits the G119S mutant enzyme. Finally, we describe a predictive model for WT An. gambiae tarsal contact toxicity of the carbamates that relies on inhibition potency, molecular volume, and polar surface area. PMID:22989775

  14. Adult behaviour of members of the Anopheles gambiae complex in the Gambia with special reference to An. melas and its chromosomal variants.

    PubMed

    Bryan, J H; Petrarca, V; Di Deco, M A; Coluzzi, M

    1987-01-01

    Polytene chromosome studies on the member species of the Anopheles gambiae complex in The Gambia and surrounding areas in Senegal led to comparative observations on bionomics of sympatric populations of An. melas and An. gambiae. Moreover, inversion polymorphisms have been analyzed in An. melas and their possible relationships with behavioural variations in endophily and anthropophily have been considered. An. melas shows a remarkably short dispersal from typical larval breeding places associated with mangrove swamps and it is definitely more zoophilic and exophilic than An. gambiae. Only a very small fraction of An. melas biting outdoor on animals rests indoors and consequently the human blood index is largely overestimated if based on the examination of house samples alone. Differences in the frequencies of 2Rn inversion karyotypes of An. melas were observed between parallel samples obtained from animal shelters and houses, from night catches on man outdoor and from night catches on main indoor and on animal outdoor. Further differences were shown by blood meal identification between human and animal fed subsamples from the same house resting samples. Non-uniform feeding and/or resting behaviour between carriers of alternative 2Rn inversion karyotypes is postulated to explain these data.

  15. Anopheles gambiae Purine Nucleoside Phosphorylase: Catalysis, Structure, and Inhibition

    SciTech Connect

    Taylor,E.; Rinaldo-Matthis, A.; Li, L.; Ghanem, M.; Hazleton, K.; Cassera, M.; Almo, S.; Schramm, V.

    2007-01-01

    The purine salvage pathway of Anopheles gambiae, a mosquito that transmits malaria, has been identified in genome searches on the basis of sequence homology with characterized enzymes. Purine nucleoside phosphorylase (PNP) is a target for the development of therapeutic agents in humans and purine auxotrophs, including malarial parasites. The PNP from Anopheles gambiae (AgPNP) was expressed in Escherichia coli and compared to the PNPs from Homo sapiens (HsPNP) and Plasmodium falciparum (PfPNP). AgPNP has kcat values of 54 and 41 s-1 for 2'-deoxyinosine and inosine, its preferred substrates, and 1.0 s-1 for guanosine. However, the chemical step is fast for AgPNP at 226 s-1 for guanosine in pre-steady-state studies. 5'-Deaza-1'-aza-2'-deoxy-1'-(9-methylene)-Immucillin-H (DADMe-ImmH) is a transition-state mimic for a 2'-deoxyinosine ribocation with a fully dissociated N-ribosidic bond and is a slow-onset, tight-binding inhibitor with a dissociation constant of 3.5 pM. This is the tightest-binding inhibitor known for any PNP, with a remarkable Km/Ki* of 5.4 x 107, and is consistent with enzymatic transition state predictions of enhanced transition-state analogue binding in enzymes with enhanced catalytic efficiency. Deoxyguanosine is a weaker substrate than deoxyinosine, and DADMe-Immucillin-G is less tightly bound than DADMe-ImmH, with a dissociation constant of 23 pM for AgPNP as compared to 7 pM for HsPNP. The crystal structure of AgPNP was determined in complex with DADMe-ImmH and phosphate to a resolution of 2.2 Angstroms to reveal the differences in substrate and inhibitor specificity. The distance from the N1' cation to the phosphate O4 anion is shorter in the AgPNP{center_dot}DADMe-ImmH{center_dot}PO4 complex than in HsPNP{center_dot}DADMe-ImmH{center_dot}SO4, offering one explanation for the stronger inhibitory effect of DADMe-ImmH for AgPNP.

  16. Distribution of the molecular forms of Anopheles gambiae and pyrethroid knock down resistance gene in Nigeria.

    PubMed

    Awolola, T S; Oyewole, I O; Amajoh, C N; Idowu, E T; Ajayi, M B; Oduola, A; Manafa, O U; Ibrahim, K; Koekemoer, L L; Coetzee, M

    2005-09-01

    We investigated the distribution of the molecular M and S forms of Anopheles gambiae and the knock down resistance (kdr) gene associated with pyrethroid and DDT resistance in A. gambiae s.s. at 13 localities across Nigeria. Two-three days old adult female mosquito reared from larval collections were tested using standard WHO procedures, diagnostic test kits and impregnated papers to assess their pyrethroid resistance status. Specimens were identified by PCR assays and characterized for the kdr gene. DNA from adult A. gambiae s.s. collected from human dwellings were also tested for the presence of the kdr gene. The overall collection was a mix of the molecular M and S forms across the mangrove (63:37%), forest (56:44%), and transitional (36:64%) ecotypes, but almost a pure collection of the S form in the Guinea and Sudan-savanna. Results of insecticide susceptibility tests showed that mosquitoes sampled at seven localities were susceptible to permethrin, deltamethrin, and DDT, but populations of A. gambiae resistant to these insecticides were recorded at six other localities mainly in the transitional and Guinea-savanna ecotypes. The kdr gene was found only in the molecular S forms, including areas where both forms were sympatric. The overall kdr frequency was low: <47% in forest, 37-48% in the transitional, and 45-53% in Guinea-savanna. The data suggest that pyrethroid resistance in A. gambiae in Nigeria is not as widespread when compared to neighbouring West African countries.

  17. Blood-feeding behavior of Anopheles gambiae and Anopheles melas in Ghana, western Africa.

    PubMed

    Tuno, Nobuko; Kjaerandsen, Jostein; Badu, Kingsley; Kruppa, Thomas

    2010-01-01

    Anopheles gambiae is the predominant malaria vector species in Ghana, western Africa, with a strong local presence of Anopheles melas Theobald along the southern coast. We studied the biting behavior of these two species of the Anopheles gambiae complex inland and at the coast in Ghana, with special attention to the local peoples' preference for outdoor sleeping. We collected mosquitoes at two sites in 2007, representing the moist semideciduous forest zone and the strand and mangrove zone, and the sampling was repeated in the dry and rainy seasons. Sampled mosquitoes were examined for species, parity and size (wing length), and we identified the hosts of their bloodmeals. We interviewed 288 of the village people to determine where and when they slept outdoors. Our study confirmed that An. gambiae is the only species of the An. gambiae complex in the Ashanti region and revealed that An. melas is highly dominant on the western coast of Ghana. Both species showed high human blood rates in indoor resting mosquito samples. More people sleep outside on the coast than inland. An. melas demonstrated high exophily. An. gambiae bit people more frequently indoors and did so more often during the dry season than in the rainy season. We suggest that the degree of exophily in An. melas may be affected by humidity and the availability of human as well as by the mosquitoes' innate habits.

  18. A test of the chromosomal theory of ecotypic speciation in Anopheles gambiae.

    PubMed

    Manoukis, Nicholas C; Powell, Jeffrey R; Touré, Mahamoudou B; Sacko, Adama; Edillo, Frances E; Coulibaly, Mamadou B; Traoré, Sekou F; Taylor, Charles E; Besansky, Nora J

    2008-02-26

    The role of chromosomal inversions in speciation has long been of interest to evolutionists. Recent quantitative modeling has stimulated reconsideration of previous conceptual models for chromosomal speciation. Anopheles gambiae, the most important vector of human malaria, carries abundant chromosomal inversion polymorphism nonrandomly associated with ecotypes that mate assortatively. Here, we consider the potential role of paracentric inversions in promoting speciation in A. gambiae via "ecotypification," a term that refers to differentiation arising from local adaptation. In particular, we focus on the Bamako form, an ecotype characterized by low inversion polymorphism and fixation of an inversion, 2Rj, that is very rare or absent in all other forms of A. gambiae. The Bamako form has a restricted distribution by the upper Niger River and its tributaries that is associated with a distinctive type of larval habitat, laterite rock pools, hypothesized to be its optimal breeding site. We first present computer simulations to investigate whether the population dynamics of A. gambiae are consistent with chromosomal speciation by ecotypification. The models are parameterized using field observations on the various forms of A. gambiae that exist in Mali, West Africa. We then report on the distribution of larvae of this species collected from rock pools and more characteristic breeding sites nearby. Both the simulations and field observations support the thesis that speciation by ecotypification is occurring, or has occurred, prompting consideration of Bamako as an independent species.

  19. A test of the chromosomal theory of ecotypic speciation in Anopheles gambiae

    PubMed Central

    Manoukis, Nicholas C.; Powell, Jeffrey R.; Touré, Mahamoudou B.; Sacko, Adama; Edillo, Frances E.; Coulibaly, Mamadou B.; Traoré, Sekou F.; Taylor, Charles E.; Besansky, Nora J.

    2008-01-01

    The role of chromosomal inversions in speciation has long been of interest to evolutionists. Recent quantitative modeling has stimulated reconsideration of previous conceptual models for chromosomal speciation. Anopheles gambiae, the most important vector of human malaria, carries abundant chromosomal inversion polymorphism nonrandomly associated with ecotypes that mate assortatively. Here, we consider the potential role of paracentric inversions in promoting speciation in A. gambiae via “ecotypification,” a term that refers to differentiation arising from local adaptation. In particular, we focus on the Bamako form, an ecotype characterized by low inversion polymorphism and fixation of an inversion, 2Rj, that is very rare or absent in all other forms of A. gambiae. The Bamako form has a restricted distribution by the upper Niger River and its tributaries that is associated with a distinctive type of larval habitat, laterite rock pools, hypothesized to be its optimal breeding site. We first present computer simulations to investigate whether the population dynamics of A. gambiae are consistent with chromosomal speciation by ecotypification. The models are parameterized using field observations on the various forms of A. gambiae that exist in Mali, West Africa. We then report on the distribution of larvae of this species collected from rock pools and more characteristic breeding sites nearby. Both the simulations and field observations support the thesis that speciation by ecotypification is occurring, or has occurred, prompting consideration of Bamako as an independent species. PMID:18287019

  20. Variant Ionotropic Receptors in the Malaria Vector Mosquito Anopheles gambiae Tuned to Amines and Carboxylic Acids

    PubMed Central

    Pitts, R. Jason; Derryberry, Stephen L.; Zhang, Zhiwei; Zwiebel, Laurence J.

    2017-01-01

    The principal Afrotropical human malaria vector mosquito, Anopheles gambiae, remains a significant threat to global health. A critical component in the transmission of malaria is the ability of An. gambiae females to detect and respond to human-derived chemical kairomones in their search for blood meal hosts. The basis for host odor responses resides in olfactory receptor neurons (ORNs) that express chemoreceptors encoded by large gene families, including the odorant receptors (ORs) and the variant ionotropic receptors (IRs). While ORs have been the focus of extensive investigation, functional IR complexes and the chemical compounds that activate them have not been identified in An. gambiae. Here we report the transcriptional profiles and functional characterization of three An. gambiae IR (AgIr) complexes that specifically respond to amines or carboxylic acids - two classes of semiochemicals that have been implicated in mediating host-seeking by adult females but are not known to activate An. gambiae ORs (AgOrs). Our results suggest that AgIrs play critical roles in the detection and behavioral responses to important classes of host odors that are underrepresented in the AgOr chemical space. PMID:28067294

  1. Inactivation of Anopheles gambiae Glutathione Transferase ε2 by Epiphyllocoumarin

    PubMed Central

    Marimo, Patience; Hayeshi, Rose; Mukanganyama, Stanley

    2016-01-01

    Glutathione transferases (GSTs) are part of a major family of detoxifying enzymes that can catalyze the reductive dehydrochlorination of dichlorodiphenyltrichloroethane (DDT). The delta and epsilon classes of insect GSTs have been implicated in conferring resistance to this insecticide. In this study, the inactivation of Anopheles gambiae GSTε2 by epiphyllocoumarin (Tral 1) was investigated. Recombinant AgGSTε2 was expressed in Escherichia coli cells containing a pET3a-AGSTε2 plasmid and purified by affinity chromatography. Tral 1 was shown to inactivate GSTε2 both in a time-dependent manner and in a concentration-dependent manner. The half-life of GSTε2 in the presence of 25 μM ethacrynic acid (ETA) was 22 minutes and with Tral 1 was 30 minutes, indicating that Tral 1 was not as efficient as ETA as an inactivator. The inactivation parameters kinact and KI were found to be 0.020 ± 0.001 min−1 and 7.5 ± 2.1 μM, respectively, after 90 minutes of incubation. Inactivation of GSTε2 by Tral 1 implies that Tral 1 covalently binds to this enzyme in vitro and would be expected to exhibit time-dependent effects on the enzyme in vivo. Tral 1, therefore, would produce irreversible effects when used together with dichlorodiphenyltrichloroethane (DDT) in malaria control programmes where resistance is mediated by GSTs. PMID:26925266

  2. Maternal mortality in rural Gambia: levels, causes and contributing factors.

    PubMed Central

    Walraven, G.; Telfer, M.; Rowley, J.; Ronsmans, C.

    2000-01-01

    A demographic study carried out in a rural area of the Gambia between January 1993 and December 1998 recorded 74 deaths among women aged 15-49 years. Reported here is an estimation of maternal mortality among these 74 deaths based on a survey of reproductive age mortality, which identified 18 maternal deaths by verbal autopsy. Over the same period there were 4245 live births in the study area, giving a maternal mortality ratio of 424 per 100,000 live births. This maternal mortality estimate is substantially lower than estimates made in the 1980s, which ranged from 1005 to 2362 per 100,000 live births, in the same area. A total of 9 of the 18 deaths had a direct obstetric cause--haemorrhage (6 deaths), early pregnancy (2), and obstructed labour (1). Indirect causes of obstetric deaths were anaemia (4 deaths), hepatitis (1), and undetermined (4). Low standards of health care for obstetric referrals, failure to recognize the severity of the problem at the community level, delays in starting the decision-making process to seek health care, lack of transport, and substandard primary health care were identified more than once as probable or possible contributing factors to these maternal deaths. PMID:10859854

  3. Strengthening health management: experience of district teams in The Gambia.

    PubMed

    Conn, C P; Jenkins, P; Touray, S O

    1996-03-01

    The lack of basic management skills of district-level health teams is often described as a major constraint to implementation of primary health care in developing countries. To improve district-level management in The Gambia, a 'management strengthening' project was implemented in two out of the three health regions. Against a background of health sector decentralization policy the project had two main objectives: to improve health team management skills and to improve resources management under specially-trained administrators. The project used a problem-solving and participatory strategy for planning and implementing activities. The project resulted in some improvements in the management of district-level health services, particularly in the quality of team planning and coordination, and the management of the limited available resources. However, the project demonstrated that though health teams had better management skills and systems, their effectiveness was often limited by the policy and practice of the national level government and donor agencies. In particular, they were limited by the degree to which decision making was centralized on issues of staffing, budgeting, and planning, and by the extent to which national level managers have lacked skills and motivation for management change. They were also limited by the extent to which donor-supported programmes were still based on standardized models which did not allow for varying and complex environments at district level. These are common problems despite growing advocacy for more devolution of decision making to the local level.

  4. Biolistic techniques for transfection of mosquito embryos (Anopheles gambiae).

    PubMed

    Mialhe, E; Miller, L H

    1994-05-01

    To compensate for the extremely low rates of transformation by DNA microinjection into mosquito embryos of Anopheles gambiae, biolistic techniques were evaluated for introduction of DNA into large numbers of mosquito embryos. Biolistic experiments were first performed with a commercially available instrument intended for this purpose, according to the recommended procedure. The amount of DNA delivered was measured by the expression of luciferase under the control of the Drosophila heat shock protein (hsp) 70 promoter. Despite attempts to optimize biolistic parameters, the level of luciferase activity was low and highly variable. Two other methods of biolistic delivery of DNA-coated particles in aqueous suspension were then evaluated. One method used the gas explosion of the commercially available instrument (mentioned above) to drive an aqueous suspension of DNA-coated particles at high pressure. This method reproducibly increased the level of expression about 100-fold without greatly reducing embryo viability. Another method, which was recently described for plant transfection, uses lower pressure to deliver the aqueous suspension of DNA-coated particles. The level of expression of luciferase and the survival of embryos were equivalent to that obtained with the instrument modified for aqueous delivery of particles. Thus, both aqueous methods offer the advantages of reproducibly delivering more DNA to the embryos. Moreover, these methods could be suitable for delivering DNA mixed with proteins, such as restriction endonucleases and integrases, that may be destroyed by ethanol precipitation used in the standard PDS-1000/He method.

  5. Plasmodium activates the innate immune response of Anopheles gambiae mosquitoes.

    PubMed Central

    Richman, A M; Dimopoulos, G; Seeley, D; Kafatos, F C

    1997-01-01

    Innate immune-related gene expression in the major disease vector mosquito Anopheles gambiae has been analyzed following infection by the malaria parasite, Plasmodium berghei. Substantially increased levels of mRNAs encoding the antibacterial peptide defensin and a putative Gram-negative bacteria-binding protein (GNBP) are observed 20-30 h after ingestion of an infected blood-meal, at a time which indicates that this induction is a response to parasite invasion of the midgut epithelium. The induction is dependent upon the ingestion of infective, sexual-stage parasites, and is not due to opportunistic co-penetration of resident gut micro-organisms into the hemocoel. The response is activated following infection both locally (in the midgut) and systemically (in remaining tissues, presumably fat body and/or hemocytes). The observation that Plasmodium can trigger a molecularly defined immune response in the vector constitutes an important advance in our understanding of parasite-vector interactions that are potentially involved in malaria transmission, and extends knowledge of the innate immune system of insects to encompass responses to protozoan parasites. PMID:9321391

  6. Long term outcome of trichiasis surgery in the Gambia

    PubMed Central

    Burton, M J; Bowman, R J C; Faal, H; Aryee, E A N; Ikumapayi, U N; Alexander, N D E; Adegbola, R A; West, S K; Mabey, D C W; Foster, A; Johnson, G J; Bailey, R L

    2005-01-01

    Background: Trichiasis surgery is believed to reduce the risk of losing vision from trachoma. There are limited data on the long term outcome of surgery and its effect on vision and corneal opacification. Similarly, the determinants of failure are not well understood. Methods: A cohort of people in the Gambia who had undergone surgery for trachomatous trichiasis 3–4 years earlier was re-assessed. They were examined clinically and the conjunctiva was sampled for Chlamydia trachomatis polymerase chain reaction (PCR) and general bacterial culture. Results: In total, 141/162 people were re-examined. Recurrent trichiasis was found in 89/214 (41.6%) operated eyes and 52 (24.3%) eyes had five or more lashes touching the globe. Corneal opacification improved in 36 of 78 previously affected eyes. There was a general deterioration in visual acuity between surgery and follow up, which was greater if new corneal opacification developed or trichiasis returned. Recurrent trichiasis was associated with severe conjunctival inflammation and bacterial infection. C trachomatis was detected in only one individual. Conclusions: Recurrent trichiasis following surgery is a common potentially sight threatening problem. Some improvement in the cornea can occur following surgery and the rate of visual loss tended to be less in those without recurrent trichiasis. The role of conjunctival inflammation and bacterial infection needs to be investigated further. Follow up of patients is advised to identify individuals needing additional surgical treatment. PMID:15834088

  7. Porcine Cysticercosis and Risk Factors in The Gambia and Senegal

    PubMed Central

    Secka, Arss; Marcotty, Tanguy; De Deken, Redgi; Van Marck, Eric; Geerts, Stanny

    2010-01-01

    During a stratified cross-sectional survey, 1705 pigs were sampled from 279 randomly selected households, 63 randomly selected communities and villages, from four study areas in The Gambia and Senegal during the period October 2007 to January 2008. Porcine cysticercosis prevalence detected by tongue inspection at animal level per study area ranged from 0.1% to 1.0%. Using an antigen-detection ELISA the seroprevalence of cysticercosis at both community/village and animal levels for the four selected study areas is: Western region 80.0% (95%CI: 52.4%–93.6%) and 4.8% (95%CI: 3.4%–6.5%), Bignona 86.7% (95%CI: 59.8%–96.6%) and 8.9% (95%CI: 5.0%–15.5%), Kolda 82.4% (95%CI: 46.8%–96.1%) and 13.2% (95%CI: 10.8%–16.0%), and Ziguinchor 81.3% (95%CI: 43.5%–96.1%) and 6.4% (95%CI: 4.0%–10.1%), respectively. No risk factors for cysticercosis were found significant in this study. This study proved that porcine cysticercosis is endemic and distributed widely in the study areas though its incidence might be suppressed by the generalised use of toilets and latrines in the study areas. PMID:20981349

  8. The molecular forms of Anopheles gambiae: A phenotypic perspective

    PubMed Central

    Lehmann, Tovi; Diabate, Abdoulaye

    2008-01-01

    The African malaria mosquito Anopheles gambiae is undergoing speciation, being split into the M and S molecular forms. Speciation is the main process promoting biological diversity, thus, new vector species might complicate disease transmission. Genetic differentiation between the molecular forms has been extensively studied, but phenotypic differences between them, the evolutionary forces that generated divergence, and the mechanisms that maintain their genetic isolation have only recently been addressed. Here, we review recent studies suggesting that selection mediated by larval predation and competition promoted divergence between temporary and permanent freshwater habitats. These differences explain the sharp discontinuity in distribution of the molecular forms between rice fields and surrounding savanna, but they can also explain the concurrent cline between humid and arid environments due to the dependence on permanent habitats in the latter. Although less pronounced, differences in adult body size, reproductive output, and longevity also suggest that the molecular forms have adapted to distinct niches. Reproductive isolation between the molecular forms is achieved by spatial swarm segregation, although within-swarm mate recognition appears to play a role in certain locations. The implications of these results to disease transmission and control are discussed and many of the gaps in our understanding are highlighted. PMID:18640289

  9. Fluoride availability from natural resources in The Gambia--implications for oral health care.

    PubMed

    Jordan, Rainer A; Markovic, Ljubisa; Gaengler, Peter

    2008-10-01

    Changing food patterns in combination with ineffective oral hygiene measures and insufficient bioavailability of fluoride from drinking water and other sources seem to impair the dental health status in developing countries, especially in the younger population. Therefore, preventive programmes in controlling dental caries progression should be based on local conditions. For mapping the drinking water fluoride content throughout The Gambia, samples of water from rural community wells, public water taps, commercial mineral water, and from the Gambia-River were measured. Additionally, fluoride concentrations of locally extracted table salt and green tea were determined. Showed the need for supplementary fluoride intake, because natural dietary fluoride availability is very low. Age-related recommendations for oral health care and for additional fluoride bioavailability are given, taking into account local socio-economic conditions in the Republic of The Gambia and similar developing countries.

  10. Efficient ΦC31 integrase-mediated site-specific germline transformation of Anopheles gambiae.

    PubMed

    Pondeville, Emilie; Puchot, Nicolas; Meredith, Janet M; Lynd, Amy; Vernick, Kenneth D; Lycett, Gareth J; Eggleston, Paul; Bourgouin, Catherine

    2014-07-01

    Current transgenic methodology developed for mosquitoes has not been applied widely to the major malaria vector Anopheles gambiae, which has proved more difficult to genetically manipulate than other mosquito species and dipteran insects. In this protocol, we describe ΦC31-mediated site-specific integration of transgenes into the genome of A. gambiae. The ΦC31 system has many advantages over 'classical' transposon-mediated germline transformation systems, because it allows integration of large transgenes at specific, characterized genomic locations. Starting from a general protocol, we have optimized steps from embryo collection to co-injection of transgene-containing plasmid and in vitro-produced ΦC31 integrase mRNA. We also provide tips for screening transgenic larvae. The outlined procedure provides robust transformation in A. gambiae, resulting in homozygous transgenic lines in ∼2-3 months.

  11. Differential effect of human ivermectin treatment on blood feeding Anopheles gambiae and Culex quinquefasciatus.

    PubMed

    Derua, Yahya A; Kisinza, William N; Simonsen, Paul E

    2015-02-27

    Widespread and large scale use of ivermectin in humans and domestic animals can have unexpected effects on non-target organisms. As a search for a possible explanation for an observed longitudinal decline in density of anopheline vector mosquitoes, but not in Culex quinquefasciatus, in an area of north-eastern Tanzania which has been exposed to ivermectin mass drug administration, this study assessed and compared the effect of human ivermectin treatment on blood feeding Anopheles gambiae and Cx. quinquefasciatus. Consenting adult volunteers were randomized into two groups to receive either ivermectin or placebo. Twenty four hours after treatment, one volunteer from each group was concurrently exposed to 50 laboratory reared An. gambiae on one arm and 50 laboratory reared Cx. quinquefasciatus on the other arm for 15-30 minutes. Engorged mosquitoes were maintained on 10% glucose solution for 12 days and observed for survival and fecundity. The experiment was repeated 15 times. Two days after the blood meals, nearly half (average 47.7% for the 15 experiments) of the blood fed An. gambiae in the ivermectin group had died while almost all in the placebo group were alive (97.2%), and the difference in survival between these two groups continued to widen on the following days. There was no clear effect of ivermectin on Cx. quinquefasciatus, which had high survival in both ivermectin and placebo group on day 2 (95.7% and 98.4%, respectively) as well as on the following days. Ivermectin completely inhibited egg laying in An. gambiae, while egg laying and subsequent development of immature stages appeared normal in the other three groups. Blood meals taken on ivermectin treated volunteers significantly reduced survival and halted fecundity of An. gambiae but had only limited or no effect on Cx. quinquefasciatus. The result suggests that widespread use of ivermectin may have contributed to the observed decline in density of An. gambiae, without similar decrease in Cx

  12. Genomic signatures of population decline in the malaria mosquito Anopheles gambiae.

    PubMed

    O'Loughlin, Samantha M; Magesa, Stephen M; Mbogo, Charles; Mosha, Franklin; Midega, Janet; Burt, Austin

    2016-03-24

    Population genomic features such as nucleotide diversity and linkage disequilibrium are expected to be strongly shaped by changes in population size, and might therefore be useful for monitoring the success of a control campaign. In the Kilifi district of Kenya, there has been a marked decline in the abundance of the malaria vector Anopheles gambiae subsequent to the rollout of insecticide-treated bed nets. To investigate whether this decline left a detectable population genomic signature, simulations were performed to compare the effect of population crashes on nucleotide diversity, Tajima's D, and linkage disequilibrium (as measured by the population recombination parameter ρ). Linkage disequilibrium and ρ were estimated for An. gambiae from Kilifi, and compared them to values for Anopheles arabiensis and Anopheles merus at the same location, and for An. gambiae in a location 200 km from Kilifi. In the first simulations ρ changed more rapidly after a population crash than the other statistics, and therefore is a more sensitive indicator of recent population decline. In the empirical data, linkage disequilibrium extends 100-1000 times further, and ρ is 100-1000 times smaller, for the Kilifi population of An. gambiae than for any of the other populations. There were also significant runs of homozygosity in many of the individual An. gambiae mosquitoes from Kilifi. These results support the hypothesis that the recent decline in An. gambiae was driven by the rollout of bed nets. Measuring population genomic parameters in a small sample of individuals before, during and after vector or pest control may be a valuable method of tracking the effectiveness of interventions.

  13. Seasonal variations in indoor resting Anopheles gambiae and Anopheles arabiensis in Kaduna, Nigeria.

    PubMed

    Rishikesh, N; Di Deco, M A; Petrarca, V; Coluzzi, M

    1985-06-01

    A longitudinal study in a guinea savanna area in Northern Nigeria showed that indoor resting samples consisted almost entirely of An. gambiae in the wet season, characterized by relatively lower temperature and higher relative humidity, whereas An. arabiensis predominated in the dry season, characterized by relatively higher temperature and lower relative humidity. A significant change was also observed in the frequency of polymorphic chromosomal inversions in the population of An. gambiae. The inverted arrangements 2Rbc, 2Rd and 2La were found more frequent in the dry season samples as compared to the wet season ones.

  14. Habitat Partitioning of Malaria Vectors in Nchelenge District, Zambia

    PubMed Central

    Das, Smita; Muleba, Mbanga; Stevenson, Jennifer C.; Norris, Douglas E.

    2016-01-01

    Nchelenge District in Luapula Province, northern Zambia, experiences holoendemic malaria despite implementation of vector control programs. The major Anopheles vectors that contribute to Plasmodium falciparum transmission in this area had not previously been well defined. Three collections performed during the 2012 wet and dry seasons and the 2013 wet season revealed Anopheles funestus sensu stricto and Anopheles gambiae sensu stricto as the main vectors, where 80–85% of each collection was composed of An. funestus. Both vectors were found to be highly anthropophilic, and An. funestus has higher sporozoite infection rates (SIRs) and entomological inoculation rates (EIRs) year-round compared with An. gambiae: SIRs of 1.8–3.0% and 0–2.5%, respectively, and EIRs of 3.7–41.5 infectious bites per 6-month period (ib/p/6mo) and 0–5.9 ib/p/6mo, respectively. Spatial and temporal changes in each vector's dynamics and bionomics were also observed. Anopheles funestus was the predominant vector in the villages near Kenani Stream in both wet and dry seasons, whereas An. gambiae was found to be the main vector in areas near Lake Mweru during the wet season. The vector data illustrate the need for broader temporal and spatial sampling in Nchelenge and present unique opportunities to further our understanding of malarial transmission and implications for malarial control in high-risk areas. PMID:27001755

  15. Rhipicephalus sanguineus sensu lato (Ixodidae) in synantropic rodents in Rio Grande do Sul, Brazil.

    PubMed

    Winkel, Kathleen Tavares; Ribeiro, Paulo Bretanha; Antunes, Lidiane Oliveira; Cárcamo, Marcial Corrêa; Vianna, Elvia Elena Silveira

    2014-01-01

    Rhipicephalus sanguineus, the brown dog tick, is responsible for maintaining and transmitting various pathogens, both in animals and human beings, and it is of great sanitary importance. This communication reports the first occurrence of Rhipicephalus sanguineus sensu lato parasitizing Rattus norvegicus in the state of Rio Grande do Sul, Brazil, and it is also the first record of this tick species parasitizing Rattus rattus in Brazil. The rodents were captured from the port area, located in the city of Pelotas, Rio Grande do Sul, Brazil. We collected 6 larvae of this tick species from 2 male R. rattus individuals, and 3 larvae from 2 female R. norvegicus individuals; parasitized specimens of both rodent species were captured from different sites within the experimental area. This record broadens the number of Rhipicephalus sanguineus sensu lato hosts in urban areas, indicating the need for continued monitoring on population density for both R. sanguineus and synanthropic rodents.

  16. Establishment of a minor groove binder-probe based quantitative real time PCR to detect Borrelia burgdorferi sensu lato and differentiation of Borrelia spielmanii by ospA-specific conventional PCR

    PubMed Central

    2010-01-01

    Background Borrelia burgdorferi sensu lato (sl), the causative agent of Lyme borreliosis, is transmitted by ticks of the genus Ixodes as vector. For identification of Borrelia infections in ticks a TaqMan™ minor groove binder (MGB) probe-based quantitative real time PCR (qPCR) was established targeting the 5S-23S intergenic spacer. Extension to a duplex qPCR included an Ixodes spp. positive control to verify successful DNA isolation. Besides qPCR, an ospA-specific conventional PCR for species-specific identification of B. spielmanii was established. Afterwards 1000 I. ricinus flagged in the city of Hanover, Germany, were investigated for B. burgdorferi sl infections followed by species identification. Furthermore, I. hexagonus ticks were investigated to proof applicability of the PCRs. Results Quantitative real time PCR (qPCR) identifying B. burgdorferi sl in ticks was able to detect 1-10 copies per reaction. B. spielmanii ospA-specific conventional PCR was also highly specific and showed no cross reactions with the other tested Borrelia species. From 1000 hanoveranian ticks 24.3% were positive compared to only 7.4% positives by dark-field microscopy. Related to tick stage 1.7% larvae, 18.1% nymphs, and 34.6% adults were positive. The most frequent species was B. garinii, followed by B. afzelii, B. spielmanii, B. valaisiana and B. burgdorferi sensu stricto (ss). 70.6% of I. ricinus were mono-infected, whereas 28.0% and 1.4% were infected with two and three Borrelia species, respectively. From 232 I. hexagonus collected from hedgehogs in different sites of Germany, qPCR detected 5.7% to be infected with B. burgdorferi sl, which were identified as B. afzelii, B. garinii and B. spielmanii. Conclusions The evaluated qPCR to detect B. burgdorferi sl in Ixodes spp. is highly specific and sensitive. As a duplex qPCR including detection of Ixodes spp. DNA it is the first DNA based technique incorporating a control for successful DNA isolation from the vector tick

  17. Infections and mixed infections with the selected species of Borrelia burgdorferi sensu lato complex in Ixodes ricinus ticks collected in eastern Poland: a significant increase in the course of 5 years.

    PubMed

    Wójcik-Fatla, Angelina; Zając, Violetta; Sawczyn, Anna; Sroka, Jacek; Cisak, Ewa; Dutkiewicz, Jacek

    2016-02-01

    In the years 2008-2009 and 2013-2014, 1620 and 1500 questing Ixodes ricinus ticks, respectively, were examined on the territory of the Lublin province (eastern Poland). The presence of three pathogenic species causing Lyme disease was investigated: Borrelia burgdorferi sensu stricto, B. afzelii and B. garinii. The proportion of I. ricinus ticks infected with B. burgdorferi sensu lato showed a highly significant increase between 2008-2009 and 2013-2014, from 6.0 to 15.3%. A significant increase was noted with regard to all types of infections with individual species: single (4.7-7.8%), dual (1.2-6.6%), and triple (0.1-0.9%). When expressed as the percent of all infections, the frequency of mixed infections increased from 21.4 to 49.2%. Statistical analysis performed with two methods (by calculating of odds ratios and by Fisher's exact test) showed that the frequencies of mixed infections in most cases proved to be significantly greater than expected. The strongest associations were found between B. burgdorferi s. s. and B. afzelii, and between B. burgdorferi s. s. and B. garinii. They appeared to be highly significant (P < 0.0001) when assessed by two methods for 2013-2014, and for the sum of findings for both time periods. The proportions of the individual species detected in the mixed infections in 2008-2009 and 2013-2014 revealed highly significant increases for B. burgdorferi s. s. and B. garinii (from 33.9 to 71.1% and from 18.2 to 82.9%, respectively), and an insignificant decrease for B. afzelii (from 51.4 to 41.6%). The proportions of the species B. burgdorferi s. s., B. afzelii and B. garinii (with combined single and mixed infections) for 2008-2009 and 2013-2014 were: 51.2/44.0 %, 30.6/24.9% and 18.2/31.1%, respectively. In conclusion, our results seem to indicate the detrimental trend of the increasing infection rate of I. ricinus ticks with B. burgdorferi s. l. in eastern Poland, and dramatic enhancement of mixed infections with individual species, which

  18. Development and evaluation of a two-step multiplex TaqMan real-time PCR assay for detection/quantification of different genospecies of Borrelia burgdorferi sensu lato.

    PubMed

    Nunes, Mónica; Parreira, Ricardo; Carreira, Teresa; Inácio, João; Vieira, Maria Luísa

    2017-09-11

    Nowadays, at least four clinically important B. burgdorferi sensu lato (s.l.) genospecies (B. afzelii, B. garinii, B. burgdorferi sensu stricto (s.s.) and B. lusitaniae) circulate in Portugal. Each genospecies has a different tropism that resuls in a diverse array of clinical manifestations. The standard diagnostic procedure used is normally simple, nevertheless, during the "window-period" phase, in which specific antibodies cannot yet be detected, diagnosis becomes difficult, and calls for reliable, sensitive and specific laboratory methods, such as molecular tests. The aim of this study was to develop and evaluate a multiplex TaqMan real-time PCR assay to infer the presence of B. burgdorferi s.l. genospecies in clinical and vector-derived samples. The assay consists of two steps: (i) a first duplex real-time PCR targeting both flaB of B. burgdorferi s.l., and an internal control (18S rDNA for tick samples or the mammal β-actin gene for clinical samples); and (ii) a second tetraplex real-time PCR targeting the flaB gene of B. afzelii, B. garinii, B. burgdorferi s.s. and B. lusitaniae. The first step revealed a high specificity and sensitivity, allowing the detection of as low as 20 genome equivalents (GE) of B. burgdorferi s.l. from isolated cultures, clinical samples and ticks. The second step revealed high specificity, but a slightly lower sensitivity (2×10(2) GE) for detection of B. afzelii, B. garinii, B. burgdorferi s.s. and B. lusitaniae in purified DNA extracts, and particularly when testing cerebrospinal fluid (CSF) samples. Nonetheless, both real-time PCR protocols were developed to be applied at the beginning of the infection, to improve early diagnosis of Lyme borreliosis (LB), where detection of Borrelia should not rely on the use of CSF samples. The assay here described is of special interest for the analysis of both environmental and clinical samples, being advantageous in the former phase screening of Lyme borreliosis, when the efficiency of

  19. Accurate and sensitive real-time PCR assays using intergenic spacer 1 region to differentiate Cryptococcus gattii sensu lato and Cryptococcus neoformans sensu lato.

    PubMed

    Tavares, Eliandro Reis; Azevedo, Caroline Souza; Panagio, Luciano Aparecido; Pelisson, Marsileni; Pinge-Filho, Phileno; Venancio, Emerson José; Barros, Tânia Fraga; Yamada-Ogatta, Sueli Fumie; Yamauchi, Lucy Megumi

    2016-01-01

    In this work, two accurate and sensitive real-time polymerase chain reaction (PCR) assays to differentiate pathogenic Cryptococcus gattii sensu lato (s.l.) and C. neoformans sensu lato (s.l.) targeting the intergenic spacer 1 (IGS1) region from rDNA locus were developed. Specific primers were designed based on their IGS1 sequence analyses and the optimal real-time PCR assays showed that the dissociation curves generated two different melting peaks, at 82.8 and 84.2ºC for C. gattii s.l. and C. neoformans s.l., respectively. No amplifications were observed in the negative template control. The minimum limit of detection of both primers was 100 plasmid copies per reaction, and they were highly specific when tested with a range of fungal DNAs. Overall, the results showed that the designed primers completely differentiated C. gattii s.l. and C. neoformans s.l. from clinical and environmental sources with great accuracy when compared to phenotypic identification, with no cross-reactivity to other fungal DNA.

  20. Divergence of the SigB regulon and pathogenesis of the Bacillus cereus sensu lato group

    PubMed Central

    2012-01-01

    Background The Bacillus cereus sensu lato group currently includes seven species (B. cereus, B. anthracis, B. mycoides, B. pseudomycoides, B. thuringiensis, B. weihenstephanensis and B. cytotoxicus) that recent phylogenetic and phylogenomic analyses suggest are likely a single species, despite their varied phenotypes. Although horizontal gene transfer and insertion-deletion events are clearly important for promoting divergence among these genomes, recent studies have demonstrated that a major basis for phenotypic diversity in these organisms may be differential regulation of the highly similar gene content shared by these organisms. To explore this hypothesis, we used an in silico approach to evaluate the relationship of pathogenic potential and the divergence of the SigB-dependent general stress response within the B. cereus sensu lato group, since SigB has been demonstrated to support pathogenesis in Bacillus, Listeria and Staphylococcus species. Results During the divergence of these organisms from a common “SigB-less” ancestor, the placement of SigB promoters at varied locations in the B. cereus sensu lato genomes predict alternative structures for the SigB regulon in different organisms. Predicted promoter changes suggesting differential transcriptional control of a common gene pool predominate over evidence of indels or horizontal gene transfer for explaining SigB regulon divergence. Conclusions Four lineages of the SigB regulon have arisen that encompass different gene contents and suggest different strategies for supporting pathogenesis. This is consistent with the hypothesis that divergence within the B. cereus sensu lato group rests in part on alternative strategies for regulation of a common gene pool. PMID:23088190

  1. Genetic Diversity of Borrelia burgdorferi Sensu Lato in Ticks from Mainland Portugal

    PubMed Central

    De Michelis, Simona; Sewell, Henna-Sisko; Collares-Pereira, Margarida; Santos-Reis, Margarida; Schouls, Leo M.; Benes, Vladimir; Holmes, Edward C.; Kurtenbach, Klaus

    2000-01-01

    To date Borrelia lusitaniae is the only genospecies of Borrelia burgdorferi sensu lato isolated from Ixodes ricinus ticks collected in Portugal and Tunisia. This suggests that the genospecies diversity of B. burgdorferi sensu lato decreases toward the southwestern margin of its Old World subtropical range. In order to further explore the genetic diversity of B. burgdorferi sensu lato from this region, 55 I. ricinus and 27 Hyalomma marginatum questing adults, collected during the spring of 1998 from a sylvatic habitat south of Lisbon, Portugal, were analyzed. Infection prevalences of 75% in I. ricinus ticks and 7% in H. marginatum ticks were detected by a nested PCR that targets the rrf (5S)-rrl (23S) spacer of B. burgdorferi sensu lato. Restriction fragment length polymorphism (RFLP) analysis of the I. ricinus-derived amplicons showed that the sequences in the majority of samples were similar to those of B. lusitaniae type strains (76% for strain PotiB1, 5% for strain PotiB3). Two novel RFLP patterns were obtained from 12% of the samples. The remaining 7% of samples gave mixed RFLP patterns. Phylogenetic analysis of rrf-rrl spacer sequences revealed a diverse population of B. lusitaniae in questing adult I. ricinus ticks (the sequences did not cluster with those of any other genospecies). This population consisted of 10 distinct sequence types, suggesting that multiple strains of B. lusitaniae were present in the local I. ricinus population. We hypothesize that B. lusitaniae has a narrow ecological niche that involves host species restricted to the Mediterranean Basin. PMID:10834965

  2. Distinct Combinations of Borrelia burgdorferi Sensu Lato Genospecies Found in Individual Questing Ticks from Europe

    PubMed Central

    Kurtenbach, Klaus; De Michelis, Simona; Sewell, Henna-Sisko; Etti, Susanne; Schäfer, Stefanie M.; Hails, Rosie; Collares-Pereira, Margarida; Santos-Reis, Margarida; Haninçová, Klára; Labuda, Milan; Bormane, Antra; Donaghy, Michael

    2001-01-01

    The genetic diversity of Borrelia burgdorferi sensu lato was assessed in individual adult Ixodes ricinus ticks from Europe by direct PCR amplification of spirochetal DNA followed by genospecies-specific hybridization. Analysis of mixed infections in the ticks showed that B. garinii and B. valaisiana segregate from B. afzelii. This and previous findings suggest that host complement interacts with spirochetes in the tick, thereby playing an important role in the ecology of Lyme borreliosis. PMID:11571205

  3. Characterization of the multicopper oxidase gene family in Anopheles gambiae

    PubMed Central

    Gorman, Maureen J.; Dittmer, Neal T.; Marshall, Jeremy L.; Kanost, Michael R.

    2008-01-01

    The multicopper oxidase (MCO) family of enzymes includes laccases, which oxidize a broad range of substrates including diphenols, and several oxidases with specific substrates such as iron, copper or ascorbic acid. We have identified five putative MCO genes in the genome of Anopheles gambiae and have cloned cDNAs encompassing the full coding region for each gene. MCO1 mRNA was detected in all developmental stages and in all of the larval and adult tissues tested. We observed an increase in MCO1 transcript abundance in the midguts and Malphighian tubules of adult females following a blood meal and in adult abdominal carcasses in response to an immune challenge. Two alternatively spliced isoforms of MCO2 mRNA were identified. The A isoform of MCO2 was previously detected in larval and pupal cuticle where it probably catalyzes sclerotization reactions (He et al., 2007). The B isoform was transcriptionally upregulated in ovaries in response to a blood meal. MCO3 mRNA was detected in the adult midgut, Malpighian tubules, and male reproductive tissues; like MCO1, it was upregulated in response to an immune challenge or a blood meal. MCO4 and MCO5 were observed primarily in eggs and in the abdominal carcass of larvae. A phylogenetic analysis of insect MCO genes identified putative orthologs of MCO1 and MCO2 in all of the insect genomes tested, whereas MCO3, MCO4 and MCO5 were found only in the two mosquito species analyzed. MCO2 orthologs have especially high sequence similarity, suggesting that they are under strong purifying selection; the A isoforms are more conserved than the B isoforms. The mosquito specific group shares a common ancestor with MCO2. This initial study of mosquito MCOs suggests that MCO2 may be required for egg development or eggshell tanning in addition to cuticle tanning, while MCO1 and MCO3 may be involved in metal metabolism or immunity. PMID:18675911

  4. A High-Affinity Adenosine Kinase from Anopheles Gambiae

    SciTech Connect

    M Cassera; M Ho; E Merino; E Burgos; A Rinaldo-Matthis; S Almo; V Schramm

    2011-12-31

    Genome analysis revealed a mosquito orthologue of adenosine kinase in Anopheles gambiae (AgAK; the most important vector for the transmission of Plasmodium falciparum in Africa). P. falciparum are purine auxotrophs and do not express an adenosine kinase but rely on their hosts for purines. AgAK was kinetically characterized and found to have the highest affinity for adenosine (K{sub m} = 8.1 nM) of any known adenosine kinase. AgAK is specific for adenosine at the nucleoside site, but several nucleotide triphosphate phosphoryl donors are tolerated. The AgAK crystal structure with a bound bisubstrate analogue Ap{sub 4}A (2.0 {angstrom} resolution) reveals interactions for adenosine and ATP and the geometry for phosphoryl transfer. The polyphosphate charge is partly neutralized by a bound Mg{sup 2+} ion and an ion pair to a catalytic site Arg. The AgAK structure consists of a large catalytic core in a three-layer {alpha}/{beta}/{alpha} sandwich, and a small cap domain in contact with adenosine. The specificity and tight binding for adenosine arise from hydrogen bond interactions of Asn14, Leu16, Leu40, Leu133, Leu168, Phe168, and Thr171 and the backbone of Ile39 and Phe168 with the adenine ring as well as through hydrogen bond interactions between Asp18, Gly64, and Asn68 and the ribosyl 2'- and 3'-hydroxyl groups. The structure is more similar to that of human adenosine kinase (48% identical) than to that of AK from Toxoplasma gondii (31% identical). With this extraordinary affinity for AgAK, adenosine is efficiently captured and converted to AMP at near the diffusion limit, suggesting an important role for this enzyme in the maintenance of the adenine nucleotide pool. mRNA analysis verifies that AgAK transcripts are produced in the adult insects.

  5. Plasmodium infection alters Anopheles gambiae detoxification gene expression

    PubMed Central

    2010-01-01

    Background Anopheles gambiae has been shown to change its global gene expression patterns upon Plasmodium infection. While many alterations are directly related to the mosquito's innate immune response, parasite invasion is also expected to generate toxic by-products such as free radicals. The current study aimed at identifying which loci coding for detoxification enzymes are differentially expressed as a function of Plasmodium berghei infection in midgut and fat body tissues. Results Using a custom-made DNA microarray, transcript levels of 254 loci primarily belonging to three major detoxification enzyme families (glutathione S-transferases, cytochrome P450 monooxygenases and esterases) were compared in infected and uninfected mosquitoes both during ookinete invasion and the release of sporozoites into the hemocoel. The greatest changes in gene expression were observed in the midgut in response to ookinete invasion. Interestingly, many detoxification genes including a large number of P450s were down-regulated at this stage. In the fat body, while less dramatic, gene expression alterations were also observed and occurred during the ookinete invasion and during the release of sporozoites into the hemocoel. While most gene expression changes were tissue-related, CYP6M2, a CYP previously associated with insecticide resistance, was over-expressed both in the midgut and fat body during ookinete invasion. Conclusions Most toxicity-related reactions occur in the midgut shortly after the ingestion of an infected blood meal. Strong up-regulation of CYP6M2 in the midgut and the fat body as well as its previous association with insecticide resistance shows its broad role in metabolic detoxification. PMID:20482856

  6. Neonatal mortality in a rural area of The Gambia.

    PubMed

    Leach, A; McArdle, T F; Banya, W A; Krubally, O; Greenwood, A M; Rands, C; Adegbola, R; de Francisco, A; Greenwood, B M

    1999-03-01

    Childhood mortality in Upper River Division, The Gambia is high, 99 per 1000 mid-year population, and 27% of deaths occur is the neonatal period. The aims of the present study were to describe patterns of neonatal death and to identify risk factors. Cause of death was investigated using a neonatal post-mortem questionnaire, and a population-based, matched case-control study was conducted to identify potential risk factors. The neonatal mortality rate in Upper River Division was 39 per 1000 live births (95% CI 36.8-41.2). The rates in the early and late neonatal periods were 21.0 (19.4-22.6) and 18.0 (16.5-19.5), respectively. Infection accounted for 57% of all deaths. In the early neonatal period, 30% of deaths were due to prematurity. Only 55% of babies who died presented for treatment and 84% died at home. Risk factors for neonatal death were primiparity (OR 2.18), previous stillbirth (OR 3.19), prolonged labour (OR 2.80) and pre-lacteal feeding (OR 3.38). A protective effect was seen in association with delivery by a trained traditional birth attendant (OR 0.34) and the application of shea nut butter, a traditional medicine, to the cord stump (OR 0.07). This study has identified the need to understand the reasons underlying the widespread use of pre-lacteal feeds and the barriers to health service use in this community in order to plan effective interventions.

  7. Echinococcus granulosus sensu lato and Taenia hydatigena in pig in southern Brazil.

    PubMed

    Monteiro, Danieli Urach; Botton, Sônia de Avila; Tonin, Alexandre Alberto; Haag, Karen Luisa; Musskopf, Germano; Azevedo, Maria Isabel; Weiblen, Carla; Ribeiro, Tatiana Correa; de la Rue, Mário Luiz

    2015-01-01

    This study aimed to identify the parasitical etiologic agents of visceral cysts in pigs from the central/northern region of Rio Grande do Sul State, Brazil. Fifty-eight cysts were found in livers during veterinary inspection of swine slaughtered from January 2008 to 2012. Collected samples were submitted to macroscopic and molecular analyzes. Polymerase chain reaction (PCR), DNA sequencing and BLAST alignment of sequences was used to molecular characterization of the samples. By PCR 10.3% (6/58) of tested samples were positive for Echinococcus granulosus sensu lato and 56.9% (33/58) for Cysticercus tenuicollis. In this study, it was verified the occurrence of larval forms of E. granulosus sensu lato and Taenia hydatigena in pig herds from the central/northern region of Rio Grande do Sul State. The presence of both parasites is relevant due to the economic losses for the meat industry. Additionally, E. granulosus sensu lato has zoonotic importance and may be infecting pig herds in southern Brazil.

  8. Detection of tick blood parasites in Egypt using PCR assay II- Borrelia burgdorferi sensu lato.

    PubMed

    Adham, Fatma K; El-Samie-Abd, Emtithal M; Gabre, Refaat M; El Hussein, Hala

    2010-12-01

    The prevalence of Borrelia burgdorferi sensu lato (s.l.), the etiologic agent of Lyme borrelosis (LB), was determined for the first time in Egypt by using polymerase chain reaction (PCR). Questing 5243 hard and soft ticks were collected from animal farms throughout Giza Governorate. DNA from 500 individual tick species was extracted and PCR was performed. Primers verified from the sequence of German strain Pko of Borrelia afzelii were used. Fragments of 642 bp were generated and sequenced. The prevalence of B. burgdorferi sensu lato (s.l.) was 28% of examined soft and hard ticks. High infection rate (66%) of B. burgdorferi s.l. was observed in both nymph and adult soft ticks Ornithodoros savignyi. Beside, the role of hard ticks as potential vectors of Lyme disease in Egypt, where the infection rate was between 0.0-50.0%. Sequence analysis of PCR product of Borrelia burgdorferi sensu lato shares high degree of similarity in sequence compared to similar species in GenBank.

  9. Analysis of the bmp Gene Family in Borrelia burgdorferi Sensu Lato

    PubMed Central

    Gorbacheva, Victoria Y.; Godfrey, Henry P.; Cabello, Felipe C.

    2000-01-01

    BmpA, BmpB, BmpC, and BmpD are homologous Borrelia burgdorferi lipoproteins of unknown functions, encoded by the bmp genes of paralogous chromosomal gene family 36. At least some of the Bmp proteins are immunogens in infected vertebrate hosts. The genetic organization of the bmp region has been characterized for a variety of B. burgdorferi sensu lato strains by Southern hybridization, PCR amplification, and DNA sequencing. All four bmp genes were present in the same relative order in all B. burgdorferi sensu lato low- and high-passage-number isolates. While there were no differences in the relative orders of the bmp genes in these species, variations in DNA sequence in the bmpD-bmpC and bmpC-bmpA intergenic regions were significantly more common than in the corresponding 3′ bmpD and bmpC coding regions. The genetic structure of the chromosomal region containing the bmp genes thus appears to be well conserved across different species of B. burgdorferi, but variations in DNA fine structure that prevent PCR primer annealing may occur in this region and make Southern hybridization much more reliable than PCR for detection of the presence of these genes. Our results also suggest that bmp gene products may be used as reagents in the preparation of vaccines and diagnostic assays to protect against and diagnose Lyme disease produced by B. burgdorferi sensu lato. PMID:10715014

  10. Life on the edge: African malaria mosquito (Anopheles gambiae s. l.) larvae are amphibious

    NASA Astrophysics Data System (ADS)

    Miller, James R.; Huang, Juan; Vulule, John; Walker, Edward D.

    2007-03-01

    Anopheles gambiae s.l. is the main vector of malaria in Sub-Saharan Africa. Here, an estimated 1 million people die every year from this disease. Despite considerable research on An. gambiae that increasingly explores sub-organismal phenomena, important facets of the field biology of this deadly insect are yet being discovered. In the current study, we used simple observational tools to reveal that the habitat of larval An. gambiae is not limited within the boundaries of temporary mud puddles, as has been the accepted generalization. Thus, control tactics aimed at immatures must consider zones larger than puddles per se. In fact, eggs are more likely to be found outside than inside puddles. Eggs can develop and larvae can emerge on mud. Larvae are then capable of three distinct modes of terrestrial displacement (two active and one passive), whereby, they can reach standing water. On mud bearing a film of water, larvae actively displace backwards by sinusoidal undulations shown to be only a slight variation of the swimming motor program. On drying mud, larvae switch to a slower and forward form of active locomotion resembling that of a crawling caterpillar. During rains, small larvae may be passively displaced by flowing rainwater so as to be deposited into puddles. These capabilities for being amphibious, along with very rapid growth and development, help explain how An. gambiae thrives in a highly uncertain and often hostile larval environment.

  11. Greenhouse gas mitigation options in the forestry sector of The Gambia: Analysis based on COMAP model

    SciTech Connect

    Jallow, B.P.

    1996-12-31

    Results of the 1993 Greenhouse Gas Emissions Inventory of The Gambia showed net CO{sub 2} emissions of over (1.66 x 10{sup 6} tons) and 1% was due to uptake by plantations (0.01 x 10{sup 6} tons). This is a clear indication that there is need to identify changes in the land-use policy, law and tenure that discourages forest clearing at the same time significantly influencing the sustainable distribution of land among forestry, rangeland and livestock, and agriculture. About 11% of the total area of The Gambia is either fallow or barren flats that once supported vegetation and hence is still capable of supporting vegetation. The US Country Study Programme has provided the Government of The Gambia through the National Climate Committee funds to conduct Assessment of Mitigation Options to Reduce Greenhouse Gas Emissions. The Forestry Sector is one area for which assessment is being conducted. The assessment is expected to end in September 1996. The Comprehensive Mitigation Analysis Process (COMAP) is one of the Models supplied to the National Climate Committee by the Lawrence Berkeley Laboratory, on behalf of the US Country Study Programme, and is being used to conduct the analysis in The Gambia.

  12. Transmission of Armillifer armillatus Ova at Snake Farm, The Gambia, West Africa

    PubMed Central

    Meyer, Michael; Oesterlein, Anett; Jaye, Assan; Frosch, Matthias; Schoen, Christoph; Pantchev, Nikola

    2011-01-01

    Visceral pentastomiasis caused by Armillifer armillatus larvae was diagnosed in 2 dogs in The Gambia. Parasites were subjected to PCR; phylogenetic analysis confirmed relatedness with branchiurans/crustaceans. Our investigation highlights transmission of infective A. armillatus ova to dogs and, by serologic evidence, also to 1 human, demonstrating a public health concern. PMID:21291598

  13. Distinct Olfactory Signaling Mechanisms in the Malaria Vector Mosquito Anopheles gambiae

    PubMed Central

    Bohbot, Jonathan D.; Jones, Patrick L.; Wang, Guirong; Zwiebel, Laurence J.

    2010-01-01

    Anopheles gambiae is the principal Afrotropical vector for human malaria, in which olfaction mediates a wide range of both adult and larval behaviors. Indeed, mosquitoes depend on the ability to respond to chemical cues for feeding, host preference, and mate location/selection. Building upon previous work that has characterized a large family of An. gambiae odorant receptors (AgORs), we now use behavioral analyses and gene silencing to examine directly the role of AgORs, as well as a newly identified family of candidate chemosensory genes, the An. gambiae variant ionotropic receptors (AgIRs), in the larval olfactory system. Our results validate previous studies that directly implicate specific AgORs in behavioral responses to DEET as well as other odorants and reveal the existence of at least two distinct olfactory signaling pathways that are active in An. gambiae. One system depends directly on AgORs; the other is AgOR-independent and requires the expression and activity of AgIRs. In addition to clarifying the mechanistic basis for olfaction in this system, these advances may ultimately enhance the development of vector control strategies, targeting olfactory pathways in mosquitoes to reduce the catastrophic effects of malaria and other mosquito-borne diseases. PMID:20824161

  14. Barriers to Participation and Retention: Engaging and Returning "Out of School" Children in the Gambia

    ERIC Educational Resources Information Center

    Daly, Angela; Mbenga, Basiru; Camara, Alpha

    2016-01-01

    This study explores the phenomenon of out-of-school children in the Gambia through the perspectives of children and families. Using mixed methods, the study reports the extent of school participation. Interviews with urban and rural out-of-school children reveal their experiences and reasons for non-enrolment or leaving school. The study…

  15. Crepuscular Behavioral Variation and Profiling of Opsin Genes in Anopheles gambiae and Anopheles stephensi (Diptera: Culicidae)

    PubMed Central

    Jenkins, Adam M.; Muskavitch, Marc A. T.

    2015-01-01

    We understand little about photopreference and the molecular mechanisms governing vision-dependent behavior in vector mosquitoes. Investigations of the influence of photopreference on adult mosquito behaviors such as endophagy and exophagy and endophily and exophily will enhance our ability to develop and deploy vector-targeted interventions and monitoring techniques. Our laboratory-based analyses have revealed that crepuscular period photopreference differs between An. gambiae and An. stephensi. We employed qRT-PCR to assess crepuscular transcriptional expression patterns of long wavelength-, short wavelength-, and ultraviolet wavelength-sensing opsins (i.e., rhodopsin-class G-protein coupled receptors) in An. gambiae and in An. stephensi. Transcript levels do not exhibit consistent differences between species across diurnal cycles, indicating that differences in transcript abundances within this gene set are not correlated with these behavioral differences. Using developmentally staged and gender-specific RNAseq data sets in An. gambiae, we show that long wavelength-sensing opsins are expressed in two different patterns (one set expressed during larval stages, and one set expressed during adult stages), while short wavelength- and ultraviolet wavelength-sensing opsins exhibit increased expression during adult stages. Genomic organization of An. gambiae opsins suggests paralogous gene expansion of long wavelength-sensing opsins in comparison with An. stephensi. We speculate that this difference in gene number may contribute to variation between these species in photopreference behavior (e.g., visual sensitivity). PMID:26334802

  16. Voices from the Gambia: Parents' Perspectives on Their Involvement in Their Children's Education

    ERIC Educational Resources Information Center

    Colley, Binta M.

    2014-01-01

    Research indicates the positive effects parental involvement can have in reinforcing learners' beliefs about their ability to succeed. In this article, the author explores the nature of parental involvement in children's education in the Republic of the Gambia. The Gambian example reemphasizes the value of parent-school partnerships as a constant…

  17. The effects of post-test counselling on condom use among prostitutes in The Gambia.

    PubMed

    Pickering, H; Quigley, M; Pépin, J; Todd, J; Wilkins, A

    1993-02-01

    To determine the effect of counselling on condom use by prostitutes. Cohort study. Field-based study in The Gambia. Thirty-one (12 HIV-positive and 19 HIV-negative) prostitutes. Post-test HIV counselling. Levels of condom use. Overall, counselling had no effect on condom use. Scarce resources should be directed towards providing condoms in bars rather than counselling.

  18. "Denuy Jangal Seen Bopp" (They Teach Themselves): Children's Music Learning in the Gambia

    ERIC Educational Resources Information Center

    Koops, Lisa Huisman

    2010-01-01

    The author investigated the teaching and learning processes among children in a suburban community of The Gambia, West Africa. Participants included children and adults in the community (N = 101). The researcher used ethnographic techniques of participant and nonparticipant observation, interviews, and song and chant collection. Data consisted of…

  19. Oviposition site preference and egg hatchability of Anopheles gambiae: effects of land cover types.

    PubMed

    Munga, Stephen; Minakawa, Noboru; Zhou, Guofa; Barrack, Okeyo-Owuor J; Githeko, Andrew K; Yan, Guiyun

    2005-11-01

    We studied the oviposition site preference and egg hatchability of Anopheles gambiae Giles with water collected from farmlands, forests, and natural wetlands. Water types significantly affected oviposition preference. Mosquitoes deposited significantly more eggs in rainwater in both the dry and wet seasons than waters from forests and wetlands, suggesting that An. gambiae prefers water with few impurities for oviposition. In the dry season, An. gambiae females also deposited significantly more eggs in waters from farmlands than those from forests and natural wetlands, but these differences were not statistically significant during the wet season. In both indoor and natural conditions, egg mortality in natural wetland habitats was significantly higher than in farmland habitats. The average water temperature in natural wetland habitats was significantly lower than farmland habitats in the natural conditions, but it remained the same under indoor experimental conditions, suggesting that factors other than water temperature play an important role in egg hatchability. Together with the findings from previous studies on the effects of land cover on larval survivorship, our results support the hypothesis that variations in habitat conditions induced by different land cover types contribute to the heterogeneous spatial distribution of An. gambiae larvae in the western Kenya highland.

  20. Low prevalence of bilateral (presumed nutritional) optic neuropathy as a cause of blindness in the Gambia.

    PubMed

    Dalmar, Abdirisak A; Hodson, Katherine E; Plant, Gordon T

    2013-09-01

    Previous reports of epidemics of optic neuropathy in Africa have mainly focused on eastern and central areas. Our study aimed to measure the prevalence of optic neuropathy in The Gambia, a West African country, and compare this prevalence with a simultaneously occurring epidemic of optic neuropathy, now considered endemic, in Tanzania. The sample population, derived from the Gambian National Blindness Survey (1996), was selected using simple random sampling. Thirty-three cases of low vision/blindness were identified where optic neuropathy was the sole cause of visual loss. Within a month, 31 cases were located and these patients underwent ophthalmic and peripheral nerve assessment and completed lifestyle questionnaires. Five of the 31 individuals were found to have bilateral symmetrical optic neuropathy. Although it was not possible to fully ascertain etiology, the phenotype is compatible with epidemic, presumed nutritional, optic neuropathy described in Tanzania. Comparative prevalence data suggest a prevalence of 0.07% in The Gambia based on a total sample size of 6873 vs 2.4% in Tanzania. Our data indicate that bilateral optic neuropathy is nonepidemic in The Gambia. Rare vitamin B12 and folate deficiencies reported in rural Gambians may explain the low prevalence because previous epidemics were due to nutrient deficiency. Our study is the only available estimate of epidemic optic neuropathy in The Gambia and, as such, provides an important contribution to our knowledge in identifying characteristics that may cause specific populations to be more susceptible to this public health burden.

  1. Meeting oxygen needs in Africa: an options analysis from the Gambia

    PubMed Central

    Hill, Sarah; Ebonyi, Augustine; Krishnan, Gautam; Njie, Ousman; Sanneh, Momodou; Jallow, Mariatou; Stevens, Warren; Taylor, Kevin; Weber, Martin W; Njai, Pamela Collier; Tapgun, Mary; Corrah, Tumani; Mulholland, Kim; Peel, David; Njie, Malick; Hill, Philip C; Adegbola, Richard A

    2009-01-01

    Abstract Objective To compare oxygen supply options for health facilities in the Gambia and develop a decision-making algorithm for choosing oxygen delivery systems in Africa and the rest of the developing world. Methods Oxygen cylinders and concentrators were compared in terms of functionality and cost. Interviews with key informants using locally developed and adapted WHO instruments, operational assessments, cost-modelling and cost measurements were undertaken to determine whether oxygen cylinders or concentrators were the better choice. An algorithm and a software tool to guide the choice of oxygen delivery system were constructed. Findings In the Gambia, oxygen concentrators have significant advantages compared to cylinders where power is reliable; in other settings, cylinders are preferable as long as transporting them is feasible. Cylinder costs are greatly influenced by leakage, which is common, whereas concentrator costs are affected by the cost of power far more than by capital costs. Only two of 12 facilities in the Gambia were found suitable for concentrators; at the remaining 10 facilities, cylinders were the better option. Conclusion Neither concentrators nor cylinders are well suited to every situation, but a simple options assessment can determine which is better in each setting. Nationally this would result in improved supply and lower costs by comparison with conventional cylinders alone, although ensuring a reliable supply would remain a challenge. The decision algorithm and software tool designed for the Gambia could be applied in other developing countries. PMID:19876543

  2. Health consequences of female genital mutilation/cutting in the Gambia, evidence into action

    PubMed Central

    2011-01-01

    Background Female Genital Mutilation/Cutting (FGM/C) is a harmful traditional practice with severe health complications, deeply rooted in many Sub-Saharan African countries. In The Gambia, the prevalence of FGM/C is 78.3% in women aged between 15 and 49 years. The objective of this study is to perform a first evaluation of the magnitude of the health consequences of FGM/C in The Gambia. Methods Data were collected on types of FGM/C and health consequences of each type of FGM/C from 871 female patients who consulted for any problem requiring a medical gynaecologic examination and who had undergone FGM/C in The Gambia. Results The prevalence of patients with different types of FGM/C were: type I, 66.2%; type II, 26.3%; and type III, 7.5%. Complications due to FGM/C were found in 299 of the 871 patients (34.3%). Even type I, the form of FGM/C of least anatomical extent, presented complications in 1 of 5 girls and women examined. Conclusion This study shows that FGM/C is still practiced in all the six regions of The Gambia, the most common form being type I, followed by type II. All forms of FGM/C, including type I, produce significantly high percentages of complications, especially infections. PMID:21967670

  3. Closing the Education Gender Gap: Estimating the Impact of Girls' Scholarship Program in the Gambia

    ERIC Educational Resources Information Center

    Gajigo, Ousman

    2016-01-01

    This paper estimates the impact of a school fee elimination program for female secondary students in The Gambia to reduce gender disparity in education. To assess the impact of the program, two nationally representative household surveys were used (1998 and 2002/2003). By 2002/2003, about half of the districts in the country had benefited from the…

  4. "No Vernacular": Tensions in Language Choice in a Sexual Health Lesson in the Gambia

    ERIC Educational Resources Information Center

    McGlynn, Caroline; Martin, Peter

    2009-01-01

    The focus of this paper is the small postcolonial country of the Gambia. As in other parts of postcolonial Africa, English plays a major role in the education system. The paper reports on the conflicts and tensions which are evident when "vernacular" languages are used in the classroom. Although the study is based on substantial periods…

  5. Situation Report--Argentina, France, Gambia, Grenada, Hungary, Nepal, and Paraguay.

    ERIC Educational Resources Information Center

    International Planned Parenthood Federation, London (England).

    Data relating to population and family planning in seven foreign countries are presented in these situation reports. Countries included are Argentina, France, Gambia, Grenada, Hungary, Nepal, and Paraguay. Information is provided, where appropriate and available, under two topics, general background and family planning situation. General…

  6. A proteogenomic analysis of Anopheles gambiae using high-resolution Fourier transform mass spectrometry.

    PubMed

    Chaerkady, Raghothama; Kelkar, Dhanashree S; Muthusamy, Babylakshmi; Kandasamy, Kumaran; Dwivedi, Sutopa B; Sahasrabuddhe, Nandini A; Kim, Min-Sik; Renuse, Santosh; Pinto, Sneha M; Sharma, Rakesh; Pawar, Harsh; Sekhar, Nirujogi Raja; Mohanty, Ajeet Kumar; Getnet, Derese; Yang, Yi; Zhong, Jun; Dash, Aditya P; MacCallum, Robert M; Delanghe, Bernard; Mlambo, Godfree; Kumar, Ashwani; Keshava Prasad, T S; Okulate, Mobolaji; Kumar, Nirbhay; Pandey, Akhilesh

    2011-11-01

    Anopheles gambiae is a major mosquito vector responsible for malaria transmission, whose genome sequence was reported in 2002. Genome annotation is a continuing effort, and many of the approximately 13,000 genes listed in VectorBase for Anopheles gambiae are predictions that have still not been validated by any other method. To identify protein-coding genes of An. gambiae based on its genomic sequence, we carried out a deep proteomic analysis using high-resolution Fourier transform mass spectrometry for both precursor and fragment ions. Based on peptide evidence, we were able to support or correct more than 6000 gene annotations including 80 novel gene structures and about 500 translational start sites. An additional validation by RT-PCR and cDNA sequencing was successfully performed for 105 selected genes. Our proteogenomic analysis led to the identification of 2682 genome search-specific peptides. Numerous cases of encoded proteins were documented in regions annotated as intergenic, introns, or untranslated regions. Using a database created to contain potential splice sites, we also identified 35 novel splice junctions. This is a first report to annotate the An. gambiae genome using high-accuracy mass spectrometry data as a complementary technology for genome annotation.

  7. Reticulate Speciation and Barriers to Introgression in the Anopheles gambiae Species Complex.

    PubMed

    Crawford, Jacob E; Riehle, Michelle M; Guelbeogo, Wamdaogo M; Gneme, Awa; Sagnon, N'Fale; Vernick, Kenneth D; Nielsen, Rasmus; Lazzaro, Brian P

    2015-11-28

    Speciation as a process remains a central focus of evolutionary biology, but our understanding of the genomic architecture and prevalence of speciation in the face of gene flow remains incomplete. The Anopheles gambiae species complex of malaria mosquitoes is a radiation of ecologically diverse taxa. This complex is well-suited for testing for evidence of a speciation continuum and genomic barriers to introgression because its members exhibit partially overlapping geographic distributions as well as varying levels of divergence and reproductive isolation. We sequenced 20 genomes from wild A. gambiae s.s., Anopheles coluzzii, Anopheles arabiensis, and compared these with 12 genomes from the "GOUNDRY" subgroup of A. gambiae s.l. Amidst a backdrop of strong reproductive isolation, we find strong evidence for a speciation continuum with introgression of autosomal chromosomal regions among species and subgroups. The X chromosome, however, is strongly differentiated among all taxa, pointing to a disproportionately large effect of X chromosome genes in driving speciation among anophelines. Strikingly, we find that autosomal introgression has occurred from contemporary hybridization between A. gambiae and A. arabiensis despite strong divergence (∼5× higher than autosomal divergence) and isolation on the X chromosome. In addition to the X, we find strong evidence that lowly recombining autosomal regions, especially pericentromeric regions, serve as barriers to introgression secondarily to the X. We show that speciation with gene flow results in genomic mosaicism of divergence and introgression. Such a reticulate gene pool connecting vector taxa across the speciation continuum has important implications for malaria control efforts.

  8. Control of pyrethroid-resistant Anopheles gambiae and Culex quinquefasciatus mosquitoes with chlorfenapyr in Benin.

    PubMed

    N'Guessan, Raphael; Boko, Pelagie; Odjo, Abiba; Knols, Bart; Akogbeto, Martin; Rowland, Mark

    2009-04-01

    To compare the efficacy of chlorfenapyr applied on mosquito nets and as an indoor residual spray against populations of Anopheles gambiae and Culex quinquefasciatus in an area of Benin that shows problematic levels of pyrethroid resistance. Eight-week trial conducted in experimental huts. Indoor residual spraying killed 82.9% of An. gambiae overall (mean mortality: 79.5%) compared to 53.5% overall (mean mortality: 61.7%) in the hut containing the lower dosed ITN. Analysis of data on a fortnightly basis showed high levels of mosquito mortality and blood-feeding inhibition during the first few weeks after treatment. Control of C. quinquefasciatus by the IRS and ITN interventions showed a similar trend to that of An. gambiae and though the average level of mortality was lower it was still much higher than with pyrethroid treatments against this population. Chlorfenapyr's reputation for being rather slow acting was evident particularly at lower dosages. The treatments showed no evidence of excito-repellent activity in this trial. Chlorfenapyr has the potential to control pyrethroid resistant populations of A. gambiae. There is a need to develop long-lasting formulations of chlorfenapyr to prolong its residual life on nets and sprayed surfaces. On nets it could be combined with a contact irritant pyrethroid to give improved protection against mosquito biting while killing pyrethroid-resistant mosquitoes that come into contact with the net.

  9. Seasonal climate effects anemotaxis in newly emerged adult anopheles gambiae giles in Mali, West Africa

    USDA-ARS?s Scientific Manuscript database

    The direction and magnitude of movement of the malaria vector Anopheles gambiae Giles has been of great interest to medical entomologists for over 70 years. This direction of movement is likely to be affected by many factors, from environmental conditions and stage of life history of the mosquito to...

  10. Barriers to Participation and Retention: Engaging and Returning "Out of School" Children in the Gambia

    ERIC Educational Resources Information Center

    Daly, Angela; Mbenga, Basiru; Camara, Alpha

    2016-01-01

    This study explores the phenomenon of out-of-school children in the Gambia through the perspectives of children and families. Using mixed methods, the study reports the extent of school participation. Interviews with urban and rural out-of-school children reveal their experiences and reasons for non-enrolment or leaving school. The study…

  11. Closing the Education Gender Gap: Estimating the Impact of Girls' Scholarship Program in the Gambia

    ERIC Educational Resources Information Center

    Gajigo, Ousman

    2016-01-01

    This paper estimates the impact of a school fee elimination program for female secondary students in The Gambia to reduce gender disparity in education. To assess the impact of the program, two nationally representative household surveys were used (1998 and 2002/2003). By 2002/2003, about half of the districts in the country had benefited from the…

  12. The effects of oviposition-site deprivation on Anopheles gambiae reproduction

    PubMed Central

    2012-01-01

    Background The African malaria mosquito, Anopheles gambiae, depends on availability of suitable surface water for oviposition. Short and long dry spells occur throughout the year in many parts of its range that limit its access to oviposition sites. Although not well understood, oviposition-site deprivation has been found to rapidly reduce egg batch size and hatch rate of several mosquito species. We conducted laboratory experiments to assess these effects of oviposition-site deprivation on An. gambiae and to evaluate the role of nutrition and sperm viability as mediators of these effects. Methods Anopheles gambiae adults (1–2 d old) from the G3 laboratory colony were assigned to the following treatment groups: oviposition-deprived (fed once and then deprived of oviposition site for 7 or 14 d), multiple-fed control (fed regularly once a week and allowed to lay eggs without delay), and age matched blood-deprived control (fed once, three days before water for oviposition was provided). Egg batch size and hatch rate were measured. In the second experiment two additional treatment groups were included: oviposition-deprived females that received either a second (supplemental) blood meal or virgin males (supplemental mating) 4 days prior to receiving water for oviposition. Results An. gambiae was highly sensitive to oviposition-site deprivation. Egg batch size dropped sharply to 0–3.5 egg/female within 14 days, due to reduced oviposition rate rather than a reduced number of eggs/batch. Egg hatch rate also fell dramatically to 0-2% within 7 days. The frequency of brown eggs that fail to tan was elevated. A supplemental blood meal, but not ‘supplemental insemination,’ recovered the oviposition rate of females subjected to oviposition-site deprivation. Similarly, a supplemental blood meal, but not ‘supplemental insemination,’ partly recovered hatch rate, but this increase was marginally significant (P < 0.069). Conclusions Even a short dry spell resulting in

  13. Kdr-based insecticide resistance in Anopheles gambiae s.s populations in

    PubMed Central

    2011-01-01

    Background The spread of insecticide resistance in the malaria mosquito, Anopheles gambiae is a serious threat for current vector control strategies which rely on the use of insecticides. Two mutations at position 1014 of the S6 transmembrane segment of domain II in the voltage gated sodium channel, known as kdr (knockdown resistance) mutations leading to a change of a Leucine to a Phenylalanine (L1014F) or to a Serine (L1014S) confer resistance to DDT and pyrethroid insecticides in the insect. This paper presents the current distribution of the kdr alleles in wild Anopheles gambiae populations in Cameroon. Results A total of 1,405 anopheline mosquitoes were collected from 21 localities throughout Cameroon and identified as An. gambiae (N = 1,248; 88.8%), An. arabiensis (N = 120; 8.5%) and An. melas (N = 37; 2.6%). Both kdr alleles 1014F and 1014S were identified in the M and S molecular forms of An. gambiae s.s. The frequency of the 1014F allele ranged from 1.7 to 18% in the M-form, and from 2 to 90% in the S-form. The 1014S allele ranged from 3-15% in the S-form and in the M-form its value was below 3%. Some specimens were found to carry both resistant kdr alleles. Conclusion This study provides an updated distribution map of the kdr alleles in wild An. gambiae populations in Cameroon. The co-occurrence of both alleles in malaria mosquito vectors in diverse ecological zones of the country may be critical for the planning and implementation of malaria vector control interventions based on IRS and ITNs, as currently ongoing in Cameroon. PMID:22035176

  14. Kdr-based insecticide resistance in Anopheles gambiae s.s populations in.

    PubMed

    Nwane, Philippe; Etang, Josiane; Chouaїbou, Mouhamadou; Toto, Jean Claude; Mimpfoundi, Rémy; Simard, Frédéric

    2011-10-28

    The spread of insecticide resistance in the malaria mosquito, Anopheles gambiae is a serious threat for current vector control strategies which rely on the use of insecticides. Two mutations at position 1014 of the S6 transmembrane segment of domain II in the voltage gated sodium channel, known as kdr (knockdown resistance) mutations leading to a change of a Leucine to a Phenylalanine (L1014F) or to a Serine (L1014S) confer resistance to DDT and pyrethroid insecticides in the insect. This paper presents the current distribution of the kdr alleles in wild Anopheles gambiae populations in Cameroon. A total of 1,405 anopheline mosquitoes were collected from 21 localities throughout Cameroon and identified as An. gambiae (N = 1,248; 88.8%), An. arabiensis (N = 120; 8.5%) and An. melas (N = 37; 2.6%). Both kdr alleles 1014F and 1014S were identified in the M and S molecular forms of An. gambiae s.s. The frequency of the 1014F allele ranged from 1.7 to 18% in the M-form, and from 2 to 90% in the S-form. The 1014S allele ranged from 3-15% in the S-form and in the M-form its value was below 3%. Some specimens were found to carry both resistant kdr alleles. This study provides an updated distribution map of the kdr alleles in wild An. gambiae populations in Cameroon. The co-occurrence of both alleles in malaria mosquito vectors in diverse ecological zones of the country may be critical for the planning and implementation of malaria vector control interventions based on IRS and ITNs, as currently ongoing in Cameroon.

  15. Discriminative feeding behaviour of Anopheles gambiae s.s. on endemic plants in western Kenya

    PubMed Central

    Manda, H.; Gouagna, L. C.; Nyandat, E.; Kabiru, E. W.; Jackson, R. R.; Foster, W. A.; Githure, J. I.; Beier, J. C.; Hassanali, A.

    2009-01-01

    Anopheles gambiae Giles s.s. (Diptera: Culicidae) is known to feed on plant sugars, but this is the first experimental study to consider whether it discriminates between plant species. Thirteen perennial plant species were selected on the basis of their local availability within the vicinity of human dwellings and larval habitats of An. gambiae s.s. in western Kenya. Groups of 100 or 200 mosquitoes were released into cages either with a cutting of one plant type at a time (single-plant assay) or with cuttings of all 13 plants simultaneously (choice assay), respectively, and left overnight. In the choice assay, direct observations of the percentages of mosquitoes perching or feeding on each plant were recorded over four 1-h periods each night. For both types of assay, mosquitoes were recaptured and the percentage that had fed on plants was assessed by testing them individually for the presence of fructose. To identify which plants the choice-assay mosquitoes had fed on, gas chromatography (GC) profiles of samples of mosquito homogenates were compared with GC profiles of extracts from relevant parts of each plant. Four of the plants that were observed to have been fed on most frequently in the choice assay (Parthenium hysterophorus L., Tecoma stans L., Ricinus communis L., and Senna didymobotrya Fresen) were also shown to have been ingested most often by mosquitoes in both types of assay, suggesting that An. gambiae is differentially responsive to this range of plants, regardless of whether the plants were presented singly or mixed together. Significantly more females than males fed on plants, with the exception of P. hysterophorus L., one of the plants most frequently fed on. For most plant species (ten of 13), GC profiles indicated that An. gambiae obtained sugars primarily from flowers. The exceptions were P. hysterophorus L., Lantana camara L. and R. communis L., on which An. gambiae fed more often from leaves and stems than from flowers. PMID:17373953

  16. Monooxygenase Levels and Knockdown Resistance (kdr) Allele Frequencies in Anopheles gambiae and Anopheles arabiensis in Kenya

    PubMed Central

    Chen, Hong; Githeko, Andrew K; Githure, John I; Mutunga, James; Zhou, Guofa; Yan, Guiyun

    2013-01-01

    Pyrethroid-treated bed nets and indoor spray are important components of malaria control strategies in Kenya. Information on resistance to pyrethroid insecticides in Anopheles gambiae and An. arabiensis populations is essential to the selection of appropriate insecticides and the management of insecticide resistance. Monooxygenase activity and knockdown resistance (kdr) allele frequency are biochemical and molecular indicators of mosquito resistance to pyrethroids. This study determined baseline information on monooxygenase activity and kdr allele frequency in anopheline mosquitoes in the western region, the Great Rift Valley-central province region, and the coastal region of Kenya. A total of 1990 field-collected individuals, representing 12 An. gambiae and 22 An. arabiensis populations was analyzed. We found significant among-population variation in monooxygenase activity in An. gambiae and An. arabiensis and substantial variability among individuals within populations. Nine out of 12 An. gambiae populations exhibited significantly higher average monooxygenase activity than the susceptible Kisumu reference strain. The kdr alleles (L1014S) were detected in three An. gambiae populations, and one An. arabiensis population in western Kenya, but not in the Rift Valley-central region and the coastal Kenya region. All genotypes with the kdr alleles were heterozygous, and the conservative estimation of kdr allele frequency was below 1% in these four populations. Information on monooxygenase activity and kdr allele frequency reported in this study provided baseline data for monitoring insecticide resistance changes in Kenya during the era when large-scale insecticide-treated bednet and indoor residual spray campaigns were being implemented. PMID:18402140

  17. Incidence, Antibiotic Susceptibility, and Toxin Profiles of Bacillus cereus sensu lato Isolated from Korean Fermented Soybean Products.

    PubMed

    Yim, Jin-Hyeok; Kim, Kwang-Yeop; Chon, Jung-Whan; Kim, Dong-Hyeon; Kim, Hong-Seok; Choi, Da-Som; Choi, In-Soo; Seo, Kun-Ho

    2015-06-01

    Korean fermented soybean products, such as doenjang, kochujang, ssamjang, and cho-kochujang, can harbor foodborne pathogens such as Bacillus cereus sensu lato (B. cereus sensu lato). The aim of this study was to characterize the toxin gene profiles, biochemical characteristics, and antibiotic resistance patterns of B. cereus sensu lato strains isolated from Korean fermented soybean products. Eighty-eight samples of Korean fermented soybean products purchased from retails in Seoul were tested. Thirteen of 26 doenjang samples, 13 of 23 kochujang samples, 16 of 30 ssamjang samples, and 5 of 9 cho-kochujang samples were positive for B. cereus sensu lato strains. The contamination level of all positive samples did not exceed 4 log CFU/g of food (maximum levels of Korea Food Code). Eighty-seven B. cereus sensu lato strains were isolated from 47 positive samples, and all isolates carried at least one enterotoxin gene. The detection rates of hblCDA, nheABC, cytK, and entFM enterotoxin genes among all isolates were 34.5%, 98.9%, 57.5%, and 100%, respectively. Fifteen strains (17.2%) harbored the emetic toxin gene. Most strains tested positive for salicin fermentation (62.1%), starch hydrolysis (66.7%), hemolysis (98.9%), motility test (100%), and lecithinase production (96.6%). The B. cereus sensu lato strains were highly resistant to β-lactam antibiotics such as ampicillin, penicillin, cefepime, imipenem, and oxacillin. Although B. cereus sensu lato levels in Korean fermented soybean products did not exceed the maximum levels permitted in South Korea (<10(4) CFU/g), these results indicate that the bacterial isolates have the potential to cause diarrheal or emetic gastrointestinal diseases. © 2015 Institute of Food Technologists®

  18. Molecular epidemiology and in vitro antifungal susceptibility testing of 108 clinical Cryptococcus neoformans sensu lato and Cryptococcus gattii sensu lato isolates from Denmark.

    PubMed

    Hagen, Ferry; Hare Jensen, Rasmus; Meis, Jacques F; Arendrup, Maiken Cavling

    2016-09-01

    Cryptococcosis is mainly caused by members of the Cryptococcus gattii/Cryptococcus neoformans species complexes. Here, we report the molecular characterisation and in vitro antifungal susceptibility of Danish clinical cryptococcal isolates. Species, genotype, serotype and mating type were determined by amplified fragment length polymorphism (AFLP) fingerprinting and qPCR. EUCAST E.Def 7.2 MICs were determined for amphotericin B, flucytosine, fluconazole, voriconazole and isavuconazole. Most isolates were C. neoformans (serotype A; n = 66) and belonged to genotype AFLP1/VNI (n = 61) or AFLP1B/VNII (n = 5) followed by Cryptococcus deneoformans (serotype D; genotype AFLP2, n = 20), C. neoformans × C. deneoformans hybrids (serotype AD; genotype AFLP3, n = 13) and Cryptococcus curvatus (n = 2). Six isolates were C. gattii sensu lato, and one isolate was a C. deneoformans × C. gattii hybrid (genotype AFLP8). All isolates were amphotericin B susceptible. Flucytosine susceptibility was uniform MIC50 of 4-8 mg l(-1) except for C. curvatus (MICs >32 mg l(-1) ). Cryptococcus gattii sensu lato isolates were somewhat less susceptible to the azoles. MICs of fluconazole (>32 mg l(-1) ), voriconazole (≥0.5 mg l(-1) ) and isavuconazole (0.06 and 0.25 mg l(-1) respectively) were elevated compared to the wild-type population for 1/19 C. deneoformans and 1/2 C. curvatus isolates. Flucytosine MIC was elevated for 1/61 C. neoformans (>32 mg l(-1) ). Antifungal susceptibility revealed species-specific differential susceptibility, but suggested acquired resistance was an infrequent phenomenon.

  19. Revisiting phylogenetic diversity and cryptic species of Cenococcum geophilum sensu lato.

    PubMed

    Obase, Keisuke; Douhan, Greg W; Matsuda, Yosuke; Smith, Matthew E

    2016-08-01

    The fungus Cenococcum geophilum Fr. (Dothideomycetes, Ascomycota) is one of the most common ectomycorrhizal fungi in boreal to temperate regions. A series of molecular studies has demonstrated that C. geophilum is monophyletic but a heterogeneous species or a species complex. Here, we revisit the phylogenetic diversity of C. geophilum sensu lato from a regional to intercontinental scale by using new data from Florida (USA) along with existing data in GenBank from Japan, Europe, and North America. The combination of internal transcribed spacer (ITS) ribosomal DNA and the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene resolved six well-supported lineages (87-100 % bootstrap values) that are closely related to each other and a seventh lineage that is phylogenetically distinct. A multi-locus analysis (small subunit (SSU), large subunit (LSU), translational elongation factor (TEF), and the largest and second-largest subunits of RNA polymerase II (RPB1 and RPB2)) revealed that the divergent lineage is the sister group to all other known Cenococcum isolates. Isolates of the divergent lineage grow fast on nutrient media and do not form ectomycorrhizas on seedlings of several pine and oak species. Our results indicate that C. geophilum sensu lato includes more phylogenetically distinct cryptic species than have previously been reported. Furthermore, the divergent lineage appears to be a non-mycorrhizal sister group. We discuss the phylogenetic diversity of C. geophilum sensu lato and argue in favor of species recognition based on phylogenetic and ecological information in addition to morphological characteristics. A new genus and species (Pseudocenococcum floridanum gen. et sp. nov.) is proposed to accommodate a divergent and putatively non-mycorrhizal lineage.

  20. Prevalence of Borrelia burgdorferi Sensu Lato in Ticks Collecte