In vitro studies on the sexual maturation of the bovine lungworm Dictyocaulus viviparus during the development of preadult larvae to adult worms.

The bovine lungworm Dictyocaulus viviparus is one of the most important parasites in grazing cattle. However, not much is known about morphology and molecular aspects of sexual maturation occurring during development of preadult larvae (L5) to adults. Since studies in the pulmonary compartments are infeasible, an in vitro cultivation method was established.

Occurrence of Bartonella henselae and Borrelia burgdorferi sensu lato co-infections in ticks collected from humans in Germany.

Bartonella (B.) henselae is the zoonotic agent of cat scratch disease. B.

Transcriptional differences between hypobiotic and non-hypobiotic preadult larvae of the bovine lungworm Dictyocaulus viviparus.

The survival of the bovine lungworm Dictyocaulus viviparus, one of the most important parasites in cattle, inside the host is ensured by arrested development during adverse environmental conditions, commonly referred to as hypobiosis. In the present study, a subtractive hybridization approach was used to compare the transcription profiles of hypobiotic and non-hypobiotic larvae (L5hyp and L5, respectively). Thereby, 75 L5hyp-enriched and 58 L5-enriched representative ESTs (rESTs) were identified.

GTP-cyclohydrolase and development in Teladorsagia circumcincta and Dictyocaulus viviparus (Nematoda: Strongylida).

GTP-Cyclohydrolase (GTP-CH) is necessary for the production of tetrahydrobiopterin, a required cofactor for the three aromatic amino acid hydroxylases and nitric oxide synthases. The gene encoding GTP-CH is transcribed at high levels in infective third larval stages of a number of parasitic trichostrongylid nematodes. We explore the potential role of GTP-CH within the processes of nematode development and environmentally-induced hypobiosis.

Ozone inhalation activates stress-responsive regions of the CNS.

Ozone (O(3)), a major component of air pollution, has considerable impact on public health. Besides the well-described respiratory tract inflammation and dysfunctions, there is accumulating evidence indicating that O(3) exposure affects brain functions. However, the mechanisms through which O(3) exerts toxic effects on the brain remain poorly understood.

Polysaccharide synthesis of the levansucrase SacB from Bacillus megaterium is controlled by distinct surface motifs.

Despite the widespread biological function of carbohydrates, the polysaccharide synthesis mechanisms of glycosyltransferases remain largely unexplored. Bacterial levansucrases (glycoside hydrolase family 68) synthesize high molecular weight, β-(2,6)-linked levan from sucrose by transfer of fructosyl units. The kinetic and biochemical characterization of Bacillus megaterium levansucrase SacB variants Y247A, Y247W, N252A, D257A, and K373A reveal novel surface motifs remote from the sucrose binding site with distinct influence on the polysaccharide product spectrum.

Larval migration in PERL chambers as an in vitro model for percutaneous infection stimulates feeding in the canine hookworm Ancylostoma caninum.

Background: Ancylostoma caninum third-stage larvae are the non-feeding infective stage of this parasite and are able to infect potential hosts via different infection routes. Since percutaneous infection is one of the most important routes and skin penetration is the first step into parasitic life, an existing in vitro model for percutaneous migration was modified and evaluated. The main parameter used to evaluate migration was the migration ratio (migrated larvae as a percentage of total number of larvae recovered).

Deep insights into Dictyocaulus viviparus transcriptomes provides unique prospects for new drug targets and disease intervention.

The lungworm, Dictyocaulus viviparus, causes parasitic bronchitis in cattle, and is responsible for substantial economic losses in temperate regions of the world. Here, we undertake the first large-scale exploration of available transcriptomic data for this lungworm, examine differences in transcription between different stages/both genders and identify and prioritize essential molecules linked to fundamental metabolic pathways, which could represent novel drug targets. Approximately 3 million expressed sequence tags (ESTs), generated by 454 sequencing from third-stage larvae (L3s) as well as adult females and males of D.

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.

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.

Antibodies to major pasture borne helminth infections in bulk-tank milk samples from organic and nearby conventional dairy herds in south-central Sweden.

The objective of this randomised pairwise survey was to compare the regional distribution of antibody levels against the three most important helminth infections in organic and conventional dairy herds in Sweden. Bulk-tank milk from 105 organic farms and 105 neighbouring conventional dairy farms with access to pasture in south-central Sweden were collected in September 2008. Samples were also collected from 8 organic and 8 conventional herds located in a much more restricted area, on the same as well as 3 additional occasions during the grazing season, to reveal evidence for seasonal patterns against cattle stomach worm (Ostertagia ostertagi).

Evaluation of a milk ELISA for the serodiagnosis of Dictyocaulus viviparus in dairy cows.

An enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies against the bovine lungworm Dictyocaulus viviparus in milk was established. This test is based on recombinant major sperm protein (MSP) as the antigen and ELISA results are expressed as optical density ratio (ODR) values. The cut-off value of the milk ELISA was determined as the arithmetic mean of negative milk samples plus three standard deviations (SD).

Glutamatergic neurotransmission in the nucleus tractus solitarii: structural and functional characteristics.

Glutamate is the main excitatory transmitter in the central nervous system. As such, it plays a major role in transmitting and processing visceral sensory information within the nucleus tractus solitarii (NTS). Here, we review current knowledge on NTS glutamatergic transmission.

The use of bulk-tank milk ELISAs to assess the spatial distribution of Fasciola hepatica, Ostertagia ostertagi and Dictyocaulus viviparus in dairy cattle in Flanders (Belgium).

Fasciola hepatica, Ostertagia ostertagi and Dictyocaulus viviparus are helminth parasites with a wide distribution and an important economic impact in cattle in temperate climates. This paper describes the spatial distribution of F. hepatica, O.

Stage-dependent transcriptional changes and characterization of paramyosin of the bovine lungworm Dictyocaulus viviparus.

The bovine lungworm Dictyocaulus viviparus is of major economic importance in cattle farming in the temperate zones. The invertebrate protein paramyosin is one of the main components of muscle thick filaments but can also exhibit immunomodulatory functions. It represents a promising vaccine candidate in parasitic helminths.

Molecular characterization and real-time PCR transcriptional analysis of Dictyocaulus viviparus major sperm proteins.

Major sperm proteins (MSPs) represent a protein family occurring in nematodes only. Identification of the 3' and 5' untranslated region (UTR) completed the so far partial msp complementary DNA sequences of the bovine lungworm Dictyocaulus viviparus. The full-length transcript contains sequence tracts consistent with the Kozak and polyadenylation consensus sequence.

Evaluation of reference genes for quantitative real-time PCR to investigate protein disulfide isomerase transcription pattern in the bovine lungworm Dictyocaulus viviparus.

Quantitative real-time PCR (qPCR) is the most sensitive technique for transcript quantification provided that gene transcription patterns are normalized to an evaluated reference gene. For Dictyocaulus viviparus, the housekeeping genes beta-tubulin, beta-actin, elongation factor 1alpha (ef-1alpha), glyceraldehyde-3-phosphatase dehydrogenase (gapdh), and 60S ribosomal protein L37a (60S rpL37a) were characterized and evaluated. Evaluation using the geNorm software revealed ef-1alpha and beta-tubulin as the most suitable reference genes, whereas the coefficient of variation approach resulted in ef-1alpha and 60S rpL37a as transcripts with the least variation among 12 developmental lungworm stages.

Development and evaluation of a recombinant antigen-based ELISA for serodiagnosis of cattle lungworm.

An optimised enzyme-linked immunosorbent assay (ELISA) for the detection of Dictyocaulus viviparous-specific antibodies was developed and evaluated following the testing of various microtitration plates and anti-bovine Ig-conjugates. Based on recombinant major sperm protein (MSP) expressed as a glutathione-S-transferase (GST) fusion protein in Escherichia coli, sera collected from 112 cattle experimentally infected with D. viviparus, from 129 helminth-naïve calves, 8 calves experimentally infected with Ostertagia ostertagi, and 2 calves infected with Cooperia oncophora were tested.

Absence of regulation of the T-type calcium current by Cav1.1, beta1a and gamma1 dihydropyridine receptor subunits in skeletal muscle cells.

The subunit structure of low voltage activated T-type Ca2+ channels is still unknown. Co-expression of dihydropyridine receptor (DHPR) auxiliary subunits with T-type alpha1 subunits in heterologous systems has produced conflicting results. In developing foetal skeletal muscle fibres which abundantly express DHPR subunits, Cav3.

A transcriptomic analysis of the adult stage of the bovine lungworm, Dictyocaulus viviparus.

Background: Lungworms of the genus Dictyocaulus (family Dictyocaulidae) are parasitic nematodes of major economic importance. They cause pathological effects and clinical disease in various ruminant hosts, particularly in young animals. Dictyocaulus viviparus, called the bovine lungworm, is a major pathogen of cattle, with severe infections being fatal.

Evaluation of the transcription level of the protein disulfide isomerase in different stages from Ancylostoma caninum with a real-time PCR assay.

The protein disulfide isomerase (PDI) is a ubiquitous protein, which contributes in building disulfide bridges. In the work presented here, the expression of the PDI in different stages of the canine hookworm Ancylostoma caninum was investigated. Third-stage larvae (L3), adults, as well as serum-stimulated and hypobiotic L3 were used.

Genetic regulation of arrested development in nematodes: are age-1 and daf-gene orthologs present in Dictyocaulus viviparus?

In opposite to the free-living soil nematode Caenorhabditis elegans, the genetic regulation of hypobiosis or inhibited or arrested development in parasitic nematodes is completely unknown. In C. elegans, the daf-genes or the age-1 gene are of major importance in signaling pathways regulating arrested development.

Differential gene expression in hypobiosis-induced and non-induced third-stage larvae of the bovine lungworm Dictyocaulus viviparus.

Hypobiosis is of particular importance in overwintering of the bovine lungworm Dictyocaulus viviparus. However, in parasitic nematodes there is no information available on the genetic mechanisms of hypobiosis. Suppression subtractive hybridisation was performed to identify upregulated transcripts of hypobiosis-induced and non-induced third-stage D.

Glutamatergic synapses in the rat nucleus tractus solitarii develop by direct insertion of calcium-impermeable AMPA receptors and without activation of NMDA receptors.

Calcium influxes through ionotropic glutamate receptors (AMPA and NMDA receptors, AMPARs and NMDARs) are considered to be critical for the shaping and refinement of neural circuits during synaptogenesis. Using a combined morphological and electrophysiological approach, we evaluated this hypothesis at the level of the nucleus tractus solitarii (NTS), a brainstem structure that is a gateway for many visceral sensory afferent fibres. We confirmed that in the NTS, the first excitatory synapses appeared at embryonic day 18.

Early expression of AMPA receptors and lack of NMDA receptors in developing rat climbing fibre synapses.

Whether nascent glutamatergic synapses acquire their AMPA receptors constitutively or via a regulated pathway triggered by pre-existing NMDA receptor activation is still an open issue. Here, we provide evidence that some glutamatergic synapses develop without expressing NMDA receptors. Using immunocytochemistry, we showed that synapses between developing rat climbing fibres and Purkinje cells expressed GluR2-containing AMPA receptors as soon as they were formed (i.

Membrane cholesterol modulates dihydropyridine receptor function in mice fetal skeletal muscle cells.

Caveolae and transverse (T-) tubules are membrane structures enriched in cholesterol and glycosphingolipids. They play an important role in receptor signalling and myogenesis. The T-system is also highly enriched in dihydropyridine receptors (DHPRs), which control excitation-contraction (E-C) coupling.