Результаты поиска

Legionella pneumophila pathogenesis in the Galleria mellonella infection model.

Legionella pneumophila is a facultative intracellular human pathogen and the etiological agent of severe pneumonia known as Legionnaires' disease. Its virulence depends on protein secretion systems, in particular, the Dot/Icm type IV secretion system (T4SS), which is essential to establish a replication-permissive vacuole in macrophages. The analysis of the role of these systems and their substrates for pathogenesis requires easy-to-use models which approximate human infection. We examined the effectiveness of the larvae of the wax moth Galleria mellonella as a new model for L. pneumophila inf…

Characterisation of the Trichinella spiralis deubiquitinating enzyme, TsUCH37, an evolutionarily conserved proteasome interaction partner.

BACKGROUND: Trichinella spiralis is a zoonotic parasitic nematode that causes trichinellosis, a disease that has been identified on all continents except Antarctica. During chronic infection, T. spiralis larvae infect skeletal myofibres, severely disrupting their differentiation state. METHODOLOGY AND RESULTS: An activity-based probe, HA-Ub-VME, was used to identify deubiquitinating enzyme (DUB) activity in lysate of T. spiralis L1 larvae. Results were analysed by immuno-blot and immuno-precipitation, identifying a number of potential DUBs. Immuno-precipitated proteins were subjected to LC/MS…

Larval environmental stress alters Aedes aegypti competence for Sindbis virus.

OBJECTIVE: To evaluate how stress at the larval stage alters adult mosquito performance and susceptibility to viral infection. METHODS: We used a model system consisting of Sindbis virus (SINV) and the yellow fever mosquito Aedes aegypti. Larvae were either reared under optimal conditions (control) or exposed to one of four types of stressors; suboptimal nutrients, starvation, elevated temperature, and a low dose of the insecticide malathion and adult females were fed SINV infectious blood meal. Differential expressions of stress, immune-specific and detoxification genes was measured in fourt…

Multi-host model-based identification of Armillifer agkistrodontis (Pentastomida), a new zoonotic parasite from China.

BACKGROUND: Pentastomiasis is a rare parasitic infection of humans. Pentastomids are dioecious obligate parasites requiring multiple hosts t … n acutus and Python molurus) as definitive hosts. Different stages of the parasite, including eggs, larvae and adults, were isolated and examined morphologically using light and electron microscopes. Phylogenetic and cluster analysis were also undertaken, focusing on the 18S rRNA and the Cox1 gene. The time for lifecycle completion was about 14 months, …

Resistance of Mexican fruit fly to quarantine treatments of high hydrostatic pressure combined with heat.

High-pressure processing (HPP) has been proposed as an alternative quarantine method against the Mexican fruit fly Anastrepha ludens Loew (Diptera: Tephritidae), which is one of the most important pests infesting mangoes, citrus, and other fruits in Mexico and other Latin-American countries. However, processing conditions used to destroy eggs and larvae also affect the shelf life of fruits. The objective of this study was to assess the biological viability of A. ludens eggs treated with HPP, establishing whether undestroyed eggs were able to develop larvae, pupae, and adults capable of reprodu…

Human trichinosis in remotes of Uttarakhand, India.

Trichinosis is a parasitic zoonosis caused by ingestion of infected meat containing larvae of Trichinella, more prevalent in developing countries. Although infection with Trichinella is globally distributed, it has been documented only rarely in India. The reports are available where Trichinella larvae were found from animals in India but, to our knowledge, only one human case has been reported from India (Punjab), so far. This is the first report of small multiple outbreaks of human trichinosis in India (2009-2011). Epidemiological, clinical, and laboratory findings of trichinosis patients be…

Type 2 immune-inducing helminth vaccination maintains protective efficacy in the setting of repeated parasite exposures.

Animal studies have demonstrated that helminth vaccines which induce type 2 immune responses can be protective. To date, however, such vacci … nst Litomosoides sigmodontis, a filarial nematode of rodents, were repeatedly exposed to irradiated larvae for 2 or 8 weeks or to non-irradiated infectious larvae for three months. Vaccination-induced parasite-specific IgE levels, parasite antigen-driven basophil interleukin 4 (IL-4) release, and Th2 skewing of the cellular immune response remained stab …

First report of Rhabdias (Nematoda: Rhabdiasoidea) from lungs of montane chameleons in Cameroon: description of two new species and notes on biology.

The lung nematodes of the genus Rhabdias parasitic in chameleons were previously only known from east Africa and Madagascar. Two new species … d in R. okuensis, presents characters of other Rhabdias from chameleons: heterogony, development of larvae through matricidal endotoky, infective larval stages with a thick, rounded caudal extremity, exuvium transformed into a thick cuticular sheeth. Each free-living female produces one larva, as in other African Rhabdias, whereas the female of R. gemel …

Comparative genomics and an insect model rapidly identify novel virulence genes of Burkholderia mallei.

Burkholderia pseudomallei and its host-adapted deletion clone Burkholderia mallei cause the potentially fatal human diseases melioidosis and … tion of reduced virulence in animal models is formidable. Therefore, Galleria mellonella (wax moth) larvae were evaluated as a surrogate host; we found that B. pseudomallei and B. mallei, but not other phylogenetically related bacteria, were highly pathogenic for this insect. More importantly, four previously characterized B. mallei mutants with reduced …

Cutting wild grapevines as a cultural control strategy for grape berry moth (Lepidoptera: Tortricidae).

A 3-yr field study was conducted at commercial grape farms to evaluate cutting wild grapevines as a cultural control strategy for grape berr … na, no differences were observed between programs in the percent of clusters infested by P. viteana larvae. Berries infested by P. viteana were collected from vineyard borders during the second and third P. viteana generations and held under controlled conditions. In all but one sample, survival of P. viteana larvae was similar between the two wild grap …

A role for Mansonia uniformis mosquitoes in the transmission of lymphatic filariasis in Uganda?

The possible role of Mansonia uniformis mosquitoes in the transmission of lymphatic filariasis was assessed in an endemic area of Uganda, by … nly few developed further. In dissections from Day 11 onwards, 4.6% (43/932) of M. uniformis had L2 larvae and 0.7% (7/932) had L3 larvae of W. bancrofti. The corresponding figures for An. gambiae s.l. were 13.4% and 4.6%, respectively. Dissection of wild caught M. uniformis (total of 6823) did not reveal any natural infections with W. bancrofti infecti …

Preservation of segmental hindbrain organization in adult frogs.

To test for possible retention of early segmental patterning throughout development, the cranial nerve efferent nuclei in adult ranid frogs were quantitatively mapped and compared with the segmental organization of these nuclei in larvae. Cranial nerve roots IV-X were labeled in larvae with fluorescent dextran amines. Each cranial nerve efferent nucleus resided in a characteristic segmental position within the clearly visible larval hindbrain rhombomeres (r). Trochlear motoneurons were located in r0, trigeminal motoneurons in r2-r3, facial branchiomotor and vestibuloacoustic efferent neurons i…

Low larval vector survival explains unstable malaria in the western Kenya highlands.

Several highland areas in eastern Africa have recently suffered from serious malaria epidemics. Some models predict that, in the short term, … t among school children (average parasite prevalence: 10%). During an extensive survey of potential larval habitats, we identified only seven habitats containing Anopheles gambiae Giles s.l. larvae. Their limited number and low larval densities suggested that their contribution to the adult vector population was small. Experiments on adult and larval su …

Imidacloprid/moxidectin topical solution for the prevention of heartworm disease and the treatment and control of flea and intestinal nematodes of cats.

Sixteen controlled laboratory studies, involving 420 kittens and cats, were conducted to evaluate the efficacy and safety of topically appli … nt of adult D. immitis infections when cats were treated 30 days after inoculation with third-stage larvae. A single treatment with this formulation also provided 88.4-100% control of adult C. felis for 35 days. Imidacloprid/moxidectin was 100% efficacious against adult Toxocara cati and 91.0-98.3% efficacious against immature adults and fourth-stage T. …

[Acaricidal activity of "Medifox" against the human itch mites Sarcoptes scabiei].

The acaricidal activity of Medifox was evaluated in terms of the itch mites to lend support to the validity of its regimen to treat human scabies. Experiments using mainly females, eggs, and larvae withdrawn from the burrows on the skin of patients with scabies were performed. Permethrin contained in 0.4% aqueous Medifox emulsion was found to affect an itch mite by contact and intestinal routes, without a marked knock-down effect; however, the signs of intoxication are irreversible and lead to the death of Medifox-treated mites. In an in vitro experiment, 100% death of specimens occurred 24-48…

Molecular cloning and characterisation of two kinds of proteins in excretory-secretory products of Trichinella pseudospiralis.

Two genes encoding Trichinella pseudospiralis excretory-secretory proteins related to the Trichinella spiralis glycoproteins were cloned and … the mRNA transcript for the Tp38 (Ts43) or Tp53 (Ts53) gene was restricted predominantly to muscle larvae. Western blots confirmed that the gene products were predominantly expressed by muscle-stage larvae. An immunolocalisation study showed the Tp38 (Ts43) and Tp53 (Ts53) proteins were present within the alpha-stichocyte and the beta-stichocyte of mus …

Питание в качестве ограничительного фактора для Aedes aegypti в контейнерах с водой.

Понимание экологических факторов, регулирующих естественное популяцие комаров Aedes aegypti, может улучшить контроль и снизить заболеваемость денге (DF) и геморрагической лихорадкой денге (DHF) в тропических районах. Мы расследовали вопрос о том, были ли незрелые Ээгипти в контейнерах для хранения воды из городских районов в условиях продовольственного ограничения. Мы использовали сопротивление голоду (число дней жизни без еды) в качестве показателя истории питания в третьей звезде Ээ. Сопротивление голоду и другие показатели незрелого успеха, такие, как время развития, выживание и масса взрос

Совпадение в аннотации оригинала
An understanding of the ecological factors that regulate natural populations of Aedes aegypti mosquitoes can improve control and reduce the … mber of days alive without food) as an indicator of the feeding history in third-instar Ae. aegypti larvae. Resistance to starvation and other measures of immature success, such as development time, survival, and adult mass, were investigated across a wide range of feeding conditions in the laboratory. Resistance to starvation of third-instar larvae and …

Biolarvicides in vector control: challenges and prospects.

Biolarvicides, based on mosquitocidal toxins of certain strains of Bacillus sphaericus and Bacillus thuringiensis var israelensis H-14 (Bti) are highly effective against mosquito larvae at very low doses and safe to other non-target organisms. During past two decades various biolarvicide formulations produced in India and abroad have been tested at Malaria Research Centre and some formulations have undergone large-scale operational trials. Biolarvicide formulations of B. sphaericus are useful in the control of Culex and certain Anopheles spp, such as An. stephensi and An. subpictus, but not mu…

Induction of hsp70 in transgenic Drosophila: biomarker of exposure against phthalimide group of chemicals.

The expression of stress genes is suggested to be a potentially sensitive indicator of any chemical or physical assault. This led us to explore the possibility of using expression of one of the major stress genes, hsp70, in Drosophila as a biomarker against phthalimide group of chemicals, which may accordingly provide an early indication of exposure to these hazardous chemicals. We exposed third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ) Bg(9) to different concentrations of the test chemicals (Captan, Captafol and Folpet) for various time intervals (2-48 h) to evaluate ex…

Morpholino-based gene knockdown screen of novel genes with developmental function in Ciona intestinalis.

In the present study, we conducted an extensive analysis to identify novel genes with developmental function among Ciona intestinalis genes … genes encode zinc-finger, transmembrane or Pbx homeodomain proteins. The morphological features of larvae of this phenotypic class varied according to the gene suppressed, suggesting that a distinct developmental event such as tissue specification or cell cycle progression was affected in each type of larva. Suppression of the remaining 26 genes result …