Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “DIPTERA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 343 records · Page 19Linked to original sources
PubMed2005

Paleohaemoproteus burmacis gen. n., sp. n. (Haemospororida: Plasmodiidae) from an Early Cretaceous biting midge (Diptera: Ceratopogonidae).

Paleohaemoproteus burmacis gen. n., sp. n. (Haemospororida: Plasmodiidae) is described from the abdominal cavity of a female biting midge (Diptera: Ceratopogonidae) preserved in 100 million year old amber from Myanmar (Burma). The description is based on the developmental stages of oocysts and sporozoites. The fossil species differs from extant species of Haemoproteus by its wide range of oocyst sizes, small sporozoites and occurrence in an extinct species of biting midge. Numerous sporozoites in the abdominal cavity suggest that the biting midge was an effective vector of this malarial parasite. Characters of the biting midge suggest that the host was a large, cold-blooded vertebrate. This is the earliest record of a malaria parasite and first indication that Early Cretaceous reptiles were infected with haemosporidial parasites.

Amber↗
PubMed2000

Description of Madathamugadia hiepei n. sp. (nematoda: Splendidofilariinae), a parasite of a South African gecko, and its development in laboratory bred Phlebotomus dubosqi (Diptera: Psychodidae).

Madathamugadia hiepei n. sp., Splendidofilariinae, a parasite of a South African gecko Pachydactylus turneri is described together with its development obtained experimentally in Phlebotomus duboscqi (Diptera: Psychodidae: Phlebotominae). This new species differs from the two small, more highly evolved groups with a short tail and atrophied postcloacal papillae, the first group consisting of two Madagascan species, M. zonosauri and M. hopluri, parasites of the Gerrhosauridae and Iguanidae, and the second containing three species from the Ethiopian Region, M. huambensis, M. versterae and M. bissani, parasites of the Scincidae. It also differs from M. ineichi, the most primitive species of the genus (cuticularised buccal capsule, no atrophy of head papillae and largest number of precloacal papillae), a parasite of the Cordylidae in South Africa. M. hiepei is close to the two species parasitic in the Gekkonidae of the Mediterranean subregion, M. ivaschkini and M. wanjii, all three of which have a post-oesophageal vulva. However, the new species can be distinguished from the Mediterranean parasites by (a) the shorter oesophagus, (b) the number and position of the cloacal papillae and (c) the microfilaria. The three filariae of this group and M. ineichi, the only ones of which aspects of the life-cycles are known, experimentally develop in phlebotomine sand flies.

Animals↗
PubMed2000

Purification and characterization of a trypsin-like enzyme with fibrinolytic activity present in the abdomen of horn fly, Haematobia irritans irritans (Diptera: Muscidae).

This work describes the purification and characterization of a trypsin-like enzyme with fibrinolytic activity present in the abdomen of Haematobia irritans irritans (Diptera: Muscidae). The enzyme was purified using a one-step process, consisting of affinity chromatography on SBTI-Sepharose. The purified protease showed one major active proteinase band on reverse zymography with 0.15% gelatin, corresponding to a molecular mass of 25.5 kDa, with maximum activity at pH 9.0. The purified trypsin-like enzyme preferentially hydrolyzed synthetic substrates with arginine residue at the P1 position. The Km values determined for three different substrates were 1.88 x 10(-4), 1.28 x 10(-4), and 1.40 x 10(-4) M for H-alpha-benzoyl-Ile-Glu-Gly-Arg-p-nitroanilide (S2222), DL-Ile-Pro-Arg-p-nitroanilide (S2288), and DL-Phe-Pip-Arg-p-nitroanilide (S2238), respectively. The enzyme was strongly inhibited by typical serine proteinase inhibitors such as SB

Animals↗
PubMed2004

Effect of potassium dichromate and fenitrothion on hemoglobins of Chironomus riparius Mg. (Diptera, Chironomidae) larvae: potential biomarker of environmental monitoring.

In an attempt to identify Chironomus hemoglobins as biomarkers for environmental monitoring, alterations in the hemoglobins in Chironomus riparius Mg. (Diptera: Chironomidae) larvae, exposed to potassium dichromate and fenitrothion, were investigated under laboratory conditions. The hemoglobins were evaluated in terms of their total contents by a cyanomethemoglobin procedure, individual components by electrophoresis of isoelectric focusing, and their oxidation by multi wavelength rapid-scanning spectrophotometry. The total hemoglobin contents increased at the high level of fenitrothion exposure. No variations in the individual hemoglobin component levels were found, by exposure to either fenitrothion or potassium dichromate. Whereas, the absorption spectra of the hemoglobins showed decreases in the peaks corresponding to the oxyhemoglobins by exposure to both compounds, but more sensitively by the chromium, which probably reflects the increase of the autoxidation of the oxyhemoglobins to methemoglobins by these compounds. These results suggest that autoxidation of the hemoglobins in Chironomus riparius seems to be a sensitive parameter in response to redox-active chemical exposure, and this biochemical parameter could be developed as a biomarker in environmental monitoring.

Animals↗
PubMed2000

Cloning of an aquaporin-like cDNA and in situ hybridization in adults of the mosquito Aedes aegypti (Diptera: Culicidae).

A cDNA encoding a putative water channel protein, aquaporin, was cloned from a cDNA library of Aedes aegypti Malpighian tubules. The cDNA encodes a 26.11 kDa protein similar to insect aquaporins from Haematobia irritans exigua (Diptera) and Cicadella viridis (Homoptera), and to mammalian aquaporin 4. Localization of the messenger RNA (mRNA) was performed by in situ hybridization of Malpighian tubules and analysed by fluorescence and confocal microscopy. The mRNA was localized in tracheolar cells associated with the Malpighian tubules. No signal was detected in the Malpighian tubule epithelium. The molecular mechanisms for water movement between tissues and tracheoles are not yet elucidated in insects. Our results suggest a model to explain fluid movements in tracheoles during insect respiration.

Aedes↗
PubMed2002

The D7 family of salivary proteins in blood sucking diptera.

The D7 subfamily of salivary proteins is widespread in blood sucking Diptera and belongs to the superfamily of pheromone/odourant binding proteins. Although D7 proteins are among the most abundant salivary proteins in adult female mosquitoes and sand flies, their role in blood feeding remains elusive. In the present work we report the sequence of seventeen novel D7 proteins, and propose an evolutionary scenario for the appearance of the several forms of this protein, based on a total of twenty-one sequences from Culex quinquefasciatus, Aedes aegypti, Anopheles gambiae, An. arabiensis, An. stephensi, An. darlingi mosquitoes and Lutzomyia longipalpis and Phlebotomus papatasi sand flies.

Aedes↗
PubMed2002

Wolbachia infections and superinfections in cytoplasmically incompatible populations of the European cherry fruit fly Rhagoletis cerasi (Diptera, Tephritidae).

Wolbachia is an obligately intracellular, maternally inherited bacterium which has been detected in many arthropods. Wolbachia infections disperse in host populations by mechanisms such as cytoplasmic incompatibility (CI). CI leads to embryonic mortality which occurs when infected males mate with uninfected females or females with a different Wolbachia strain. Populations of the European cherry fruit fly Rhagoletis cerasi (Diptera, Tephritidae) were found to be infected by two different Wolbachia strains, wCer1 and wCer2. Superinfections with both strains occurred throughout southern and central Europe and infections with wCer1 were found in northern, western and eastern Europe. Strong unidirectional CI between European populations of R. cerasi were first reported in the 1970s. From the conformity in the recent geographical distribution of the Wolbachia infections and the CI expression patterns found 25 years ago it was deduced that wCer2 potentially causes CI in R. cerasi. The comparison of the geographical distributions indicated that wCer1 + 2 must have spread into wCer1-infected populations in some areas. In other regions, a spread of wCer1 + 2 was probably prevented by dispersal barriers. There, a sharp transition from infected to superinfected populations suggested regional isolation between wCer1 and wCer1 + 2-infected populations.

Animals↗
PubMedDate not supplied

Characterization of the Hox cluster from the mosquito Anopheles gambiae (Diptera: Culicidae).

The Hox genes have been found to encode transcription factors, which specify the morphological identity of structures along the anteroposterior axis of animals ranging from worms to mice. The canonical set of nine genes is organized in a cluster in the genome of several protostomes and deuterostomes. However, within insects, whereas the Hox genes are organized in a single cluster in the beetle Tribolium castaneum, they are split into two separate groups in the flies Drosophila melanogaster and Drosophila virilis. The significance of a split Hox cluster is unknown and has been observed in only one organism outside the Drosophila lineage: the nematode Caenorhabditis elegans. We have cloned a majority of the Hox genes from the mosquito Anopheles gambiae (Diptera: Culicidae) and compared their genomic organization with that of Tribolium and Drosophila to determine if a split Hox cluster is found in dipterans aside from the Drosophilidae. We find that the Hox genes in Anopheles, as in Tribolium, are organized in a single cluster that spans a genomic region of at least 700 kb. This finding suggests that, within the insect genome, the partition of the Hox cluster may have evolved exclusively within the Drosophila lineage. The genomic structures of the resident genes, however, appear to be largely conserved between A. gambiae and D. melanogaster.

Amino Acid Sequence↗
PubMedDate not supplied

Coevolution in bicoid-dependent promoters and the inception of regulatory incompatibilities among species of higher Diptera.

To what extent and in what way do gene promoters and their transacting regulatory proteins coevolve? In this and in earlier publications we show that the Bicoid-dependent promoters of the segmentation genes hunchback and tailless in species of higher Diptera (Drosophila, Musca, Calliphora, and Lucilia) are different with respect to the copy number, spacing, sequence, and orientation of Bicoid binding sites. At the same time there are significant amino acid differences in the Bicoid homeodomain. To test these interspecific differences, we used a series of functional assays, starting with the analysis of Bicoid binding affinities of individual sites, through to transgene rescue experiments, to compare within-species with between-species mixtures of Bicoid homeodomains and hunchback or tailless promoters. We observed that components taken from different species interact with less efficiency compared with those taken from within the same species. Our interpretation is that such interspecific incompatibilities are a consequence of interactive genetic elements coevolving one with another, hence maintaining functional compatibility within each species. At the same time such a process allows differences to accumulate between species regarding the precise molecular basis whereby the common function is effected.

Animals↗
PubMed2004

Is Lutzomyia serrana (Diptera, Psychodidae, Phlebotominae) present in Ecuador?

We describe a multivariate metric comparison of three sandfly species showing strong differences in size, which questions the geographical distribution of one of them. Two species are represented by a single population (L. robusta and L. guilvardae) and one by two populations (L. serrana). All of them belong to the series serrana (Diptera, Psychodidae, Phlebotominae). The morphometric data confirm that L. guilvardae is a distinct species. However, they suggest that L. robusta and L. serrana in Ecuador are the same taxon, and that it is distinguishable from the population of L. serrana in Bolivia. A multilocus enzyme electrophoresis analysis comparing L. serrana in Bolivia and L. robusta in Ecuador adds further evidence that these two populations are distinct species. Thus, our data seem to indicate that, in Ecuador, the population previously identified as L. serrana is actually the same species as the allopatric population previously identified as L. robusta. Accepting L. serrana in Ecuador as small-sized L. robusta, the resulting geographic distribution of this latter becomes in closer agreement with ecology and epidemiology.

Animals↗
PubMed2006

First survey of seasonal abundance and daily activity of Stomoxys spp. (Diptera: Muscidae) in Kamphaengsaen Campus, Nakornpathom province, Thailand.

The seasonal changes and the daily activity of Stomoxyine species (Diptera: Muscidae) were examined, using Vavoua traps, in a dairy and a beef cattle farm in Nakhonpathom province, Thailand during July 2004 to June 2005. Over this period, Stomoxys calcitrans was the most commonly trapped species, followed by S. sitiens and S. indica. For the later species, this is the first report of its presence in Thailand. A total of 80 % of flies were captured during the rainy season from May to October and 20 % during the dry season from November to April. No major difference of fly density was observed between the dairy and the beef cattle farm. The activity pattern of S. calcitrans was diurnal with a peak between 08:00 am to 10:00 am and another less marked one in the afternoon. The activity pattern of S. sitiens and S. indica was mainly crepuscular with 2 peaks, early in the morning (06:00 a.m.) and late in the afternoon (6:00 p.m.). Those species are important pests of livestock in Thailand, where they are known as a mechanical vector of trypanosomes. A better knowledge of their ecology is a prerequisite for more efficient control measures.

Animals↗
PubMed2004

Functional significance of phytochemical lures to dacine fruit flies (Diptera: Tephritidae): an ecological and evolutionary synthesis.

While lures of plant origin are vital tools in dacine (Diptera: Tephritidae) pest management, the ecological and evolutionary significance of this lure response remains enigmatic. Two hypotheses (the ancestral host hypothesis and sexual selection by female choice) have been invoked to explain the functional significance of these chemicals to dacine fruit flies. These hypotheses are often treated as alternatives to one another and evidence favouring one is used to reject the other. This review highlights that these two hypotheses are not logical alternatives to each other as the ancestral host hypothesis attempts to explain the ultimate function of the response of Dacinae to these plant-derived parapheromones while the sexual selection hypothesis provides a proximate explanation for lure response. Research on lure response, dacine mating behaviour, functional significance of lures, plant phylogeny and biochemistry and dacine pheromone chemistry are used to evaluate the evidence in relation to both these hypotheses. Some of the key findings are that there is evidence both in support of and against these two hypotheses. Response of fruit flies to related phenyl propanoids to those commonly used as lures in pest management and distribution of phenyl propanoids attractive to dacines among plant orders strongly support the ancestral host hypothesis. Evidence from pheromone chemistry, dacine mating behaviour and the functional significance of lures both support and contradict the sexual selection hypothesis. Lures appear to have different proximate functions in different dacine species. Considerably greater research is needed to clarify the functional role of phytochemical lures to dacine fruit flies. The two prevalent hypotheses should be investigated independently. Specific research on dacine phylogeny and distribution of lures in plants in relation to ecological roles played by adult dacines is required to elucidate the ultimate roles of the chemicals. Exploration of female response to lures and the behavioural consequences of dacine response to these chemicals to both the insect and plant may shed light on the proximate functions of these chemicals.

Animals↗
PubMed2006

New contributions towards the understanding of the phylogenetic relationships among economically important fruit flies (Diptera: Tephritidae).

Fruit flies (Diptera: Tephritidae) are a species-rich and economically important group. The phylogenetic relationships among the many taxa are still to be fully resolved and the monophyly of several groups is still to be confirmed. This paper reports a study of the phylogenetic relationships among 23 economically important tephritid species (representing several major lineages of the family) which examines the sequence of a region of mitochondrial DNA encompassing the cytb, tRNA(Ser) and ND1 genes. Substitutions characteristic of particular taxa were found that could help classify members of the family at any developmental stage. The trees obtained by the maximum parsimony, neighbour joining and maximum likelihood methods were generally compatible with present morphological classification patterns. However, the data reveal some characteristics of the phylogenetic relationships of this family that do not agree with present classifications. The results support the probable non-monophyletic nature of the subfamily Trypetinae and suggest that Bactrocera cucurbitae (Coquillet) is more closely related to the genus Dacus than to other species of Bactrocera.

Animals↗
PubMed2001

Seasonal and nocturnal landing/biting behaviour of Phlebotomus argentipes (Diptera: Psychodidae).

The nocturnal activity of Phlebotomus argentipes (Diptera: Psychodidae), the main vector of Leishmania donovani in India, was studied throughout a year, with monthly collections, between 18.00 and 06.00 hours, of the sandflies landing on 15 humans and 15 cows in the village of Bahapur, Patna district. The cattle appeared to be better as bait, since more than five female P. argentipes were caught on them for each one caught on the human bait. Overall, although P. argentipes were caught during each collection hour from 18.00--06.00 hours, the numbers caught landing/biting peaked at 23.00--24.00 hours. There were, however, slight seasonal variations in the timing of this peak in activity. The numbers of P. argentipes caught/collection night also varied with season, being significantly higher during the summer than during the rainy season or winter (P < 0.01 for each), and apparently inversely correlated with rainfall. Male P. argentipes were caught in much higher numbers than the females of this species, with female:male ratios of 1:8 for the flies caught on human bait and of 1:13 for those collected from cattle. If the probability of a female P. argentipes being infected with L. donovani does not vary with season, peak transmission of this parasite to humans probably occurs between February and May, at the middle of night.

Animals↗
PubMed1995

Drastic reduction of populations of Simulium sirbanum (Diptera: Simuliidae) in central Sierra Leone after 5 years of larviciding operations by the Onchocerciasis Control Programme.

The major vectors of the blinding form of human onchocerciasis in West Africa are two blackfly species, Simulium sirbanum and Simulium damnosum s.s. (Diptera: Simuliidae), identified at the adult stage as the 'savanna group' of the Simulium damnosum complex. In 1988, in the central part of Sierra Leone, the average daily biting rate (females/man/day) by savanna blackflies (mostly S. sirbanum) during the peak of the dry season (April-May) was 59.9, making up 69.1% of total captures on average. There was evidence of a strong long-range immigration of adult females of S. sirbanum through eastern Guinea in the dry season, with a reverse movement towards Guinea in the rainy season. Therefore, in 1989, the World Health Organization's Onchocerciasis Control Programme (OCP) extended its vector control operations from central West Africa to rivers of central and northern Sierra Leone, and to rivers of eastern Guinea. Four years of efficient larviciding drastically reduced adult populations of S. sirbanum in Sierra Leone. In the peak of the dry seasons of 1993 and 1994, the average biting rate by savanna blackflies in central Sierra Leone had dropped to 1.0, making up only 4.3% of total captures on average. Yearly biting rates by S. sirbanum in central Sierra Leone were therefore reduced to 2% of their pre-intervention levels. Based on larval samples, the S. sirbanum has been replaced by two forest species, S. leonense in the south and S. squamosum in the north. Since 1992, it has been possible to calculate accurate transmission rates for blinding onchocerciasis, based on DNA-probe identifications. From 1993, the risk of transmission has not only been reduced by vector control but also by mass distribution of ivermectin to rural communities. In terms of control strategy, the authors conclude that larviciding operations could be alleviated in central Sierra Leone without increasing the risk of blinding onchocerciasis transmission, as long as the migration of S. sirbanum through eastern Guinea and northern Sierra Leone is prevented.

Animals↗
PubMed1996

Comparison of the sex-pheromone components of Lutzomyia longipalpis (Diptera:Psychodidae) from areas of visceral and atypical cutaneous leishmaniasis in Honduras and Cost Rica.

The terpene components of extracts prepared from male Lutzomyia longipalpis (Diptera: Psychodidae) collected from four sites in Honduras and one in Costa Rica were analysed by high-performance liquid chromatography, gas chromatography and coupled gas chromatography--mass spectrometry. The terpene components of Lu. longipalpis from other regions of South America have previously been shown to be sex pheromones. The flies from the four areas of Honduras, where Leishmania chagasi infection may lead to visceral or atypical cutaneous leishmaniasis, were found to be homogenous, all producing 9-methylgermacrene-B. Three types of terpene (9-methylgermacrene-B, a novel homosesquiterpene and a small amount of diterpene) were detected in pools of flies from Liberia, Costa Rica, where only atypical cutaneous leishmaniasis has been found. These results indicate that there are probably at least two and possibly three distinct populations of Lu. longipalpis in this region. The clinical manifestation of Leishmania chagasi infection does not appear to be dependent on which population of Lu. longipalpis transmitted the parasite.

Animals↗
PubMed2005

Evolutionary and structural analysis of the cytochrome c oxidase subunit I (COI) gene from Haematobia irritans, Stomoxys calcitrans and Musca domestica (Diptera: Muscidae) mitochondrial DNA.

This work describes the molecular characterization of the cytochrome c oxidase subunit I (COI) gene of the mitochondrial DNA from three species of great medical and veterinary importance: the horn fly, Haematobia irritans, the stable fly, Stomoxys calcitrans and the house fly, Musca domestica (Diptera: Muscidae) (Linnaeus). The nucleotide sequence in all species was 1536 bp in size and coded for a 512 amino acid peptide. The nucleotide bias for an A+T-rich sequence is linked to three features: a high A+T content throughout the entire gene, a high A+T content in the third codon position, and a predominance of A+T-rich codons. An anomalous TCG (serine) start codon was identified. Comparative analysis among members of the Muscidae, Scatophagidae, Calliphoridae and Drosophilidae showed high levels of nucleotide sequence conservation. Analysis of the divergent amino acids and COI protein topologies among these three Muscidae species agreed with the evolutionary model suggested for the insect mitochondrial COI protein. The characterization of the structure and evolution of this gene could be informative for further evolutionary analysis of dipteran species.

Amino Acids↗