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The Journal of Allergy and Clinical... Apr 2008Evidence indicates that infection with Ascaris lumbricoides may promote development of allergy and asthma. (Comparative Study)
Comparative Study
BACKGROUND
Evidence indicates that infection with Ascaris lumbricoides may promote development of allergy and asthma.
OBJECTIVE
To study the role of tropomyosin, a pan-allergen in invertebrates, in IgE responses to A lumbricoides.
METHODS
Recombinant A lumbricoides and Periplaneta americana tropomyosins were expressed in Pichia pastoris. Levels of IgE to tropomyosins from A lumbricoides and P americana were determined by chimeric ELISA in sera from 119 children living in a parasite-endemic area and 112 patients with cockroach allergy from the allergy clinics. Presence of tropomyosin in A lumbricoides larvae at L3 stage was evaluated by immunofluorescence using mAb 1A6, directed against mite tropomyosin. Molecular modeling of P americana and A lumbricoides tropomyosins was performed by using the MODELLER program.
RESULTS
A lumbricoides tropomyosin showed 69% to 98% sequence identity to tropomyosins from other invertebrates. The predicted structure of A lumbricoides tropomyosin was similar to that of P americana tropomyosin and showed the characteristic coiled-coil structure. Strong correlation was found for IgE antibodies to tropomyosins from A lumbricoides and P americana in sera from children living in a parasite-endemic area and from patients with cockroach allergy. Larvae of A lumbricoides reacted strongly with mAb 1A6.
CONCLUSION
Tropomyosin induces IgE responses in A lumbricoides-infected children and in patients allergic to cockroach.
Topics: Adolescent; Adult; Amino Acid Sequence; Animals; Ascaris lumbricoides; Asthma; Child; Child, Preschool; Cross Reactions; Humans; Hypersensitivity; Immunoglobulin E; Middle Aged; Molecular Sequence Data; Periplaneta; Tropomyosin
PubMed: 18275995
DOI: 10.1016/j.jaci.2007.12.1147 -
Mitochondrial DNA Aug 2011The genome length of the Ascaris lumbricoides, human parasitic roundworm, is 14,281 bp with a nucleotide composition of 22.1% A, 49.8% T, 7.8% C, and 20.3% G. The genome...
The genome length of the Ascaris lumbricoides, human parasitic roundworm, is 14,281 bp with a nucleotide composition of 22.1% A, 49.8% T, 7.8% C, and 20.3% G. The genome consists of 12 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and 1 control region.
Topics: Animals; Ascariasis; Ascaris lumbricoides; Base Composition; DNA, Mitochondrial; Genes, Mitochondrial; Genes, rRNA; Genome, Helminth; Genome, Mitochondrial; Humans; RNA, Transfer; Sequence Analysis, DNA
PubMed: 22040074
DOI: 10.3109/19401736.2011.624608 -
Advances in Parasitology 1998
Review
Topics: Animals; Ascariasis; Ascaris lumbricoides; China; Drugs, Chinese Herbal; Humans; Prevalence
PubMed: 9734293
DOI: 10.1016/s0065-308x(08)60423-6 -
Lung-stage protein profile and antigenic relationship between Ascaris lumbricoides and Ascaris suum.The Journal of Parasitology Aug 2002The protein profile and antigenic properties of lung-stage larvae of Ascaris lumbricoides and A. suum were studied using 2-dimensional electrophoresis and immunoblot... (Comparative Study)
Comparative Study
The protein profile and antigenic properties of lung-stage larvae of Ascaris lumbricoides and A. suum were studied using 2-dimensional electrophoresis and immunoblot analysis, respectively. The protein profiles of the 2 parasites were identical except for the presence of only 1 major protein spot specific for each. There was a complete cross-reactivity between the 2 parasites at the immunological level, and no specific antigen was recognized using specific antibody raised against the 2 parasites in rabbits.
Topics: Animals; Antigens, Helminth; Ascaris lumbricoides; Ascaris suum; Cross Reactions; Electrophoresis, Gel, Two-Dimensional; Female; Helminth Proteins; Humans; Immunoblotting; Larva; Lung; Species Specificity; Swine
PubMed: 12197147
DOI: 10.1645/0022-3395(2002)088[0826:LSPPAA]2.0.CO;2 -
BioMed Research International 2017The reuse of reclaimed water from wastewater depuration is a widespread and necessary practice in many areas around the world and must be accompanied by adequate and...
The reuse of reclaimed water from wastewater depuration is a widespread and necessary practice in many areas around the world and must be accompanied by adequate and continuous quality control. is one of the soil-transmitted helminths (STH) with risk for humans due to its high infectivity and an important determinant of transmission is the inadequacy of water supplies and sanitation. The World Health Organization (WHO) recommends a limit equal to or lower than one parasitic helminth egg per liter, to reuse reclaimed water for unrestricted irrigation. We present two new protocols of DNA extraction from large volumes of reclaimed water. Quantitative PCR (qPCR) and digital PCR (dPCR) were able to detect low amounts of eggs. By using the first extraction protocol, which processes 500 mL of reclaimed water, qPCR can detect DNA concentrations as low as one egg equivalent, while dPCR can detect DNA concentrations as low as five egg equivalents. By using the second protocol, which processes 10 L of reclaimed water, qPCR was able to detect DNA concentrations equivalent to 20 eggs. This fact indicated the importance of developing new methodologies to detect helminth eggs with higher sensitivity and precision avoiding possible human infection risks.
Topics: Animals; Ascariasis; Ascaris lumbricoides; Eggs; Helminths; Humans; Parasite Egg Count; Real-Time Polymerase Chain Reaction; Wastewater
PubMed: 28377928
DOI: 10.1155/2017/7515409 -
ELife Nov 2020Human ascariasis is a major neglected tropical disease caused by the nematode . We report a 296 megabase (Mb) reference-quality genome comprised of 17,902 protein-coding...
Human ascariasis is a major neglected tropical disease caused by the nematode . We report a 296 megabase (Mb) reference-quality genome comprised of 17,902 protein-coding genes derived from a single, representative worm. An additional 68 worms were collected from 60 human hosts in Kenyan villages where pig husbandry is rare. Notably, the majority of these worms (63/68) possessed mitochondrial genomes that clustered closer to the pig parasite than to . Comparative phylogenomic analyses identified over 11 million nuclear-encoded SNPs but just two distinct genetic types that had recombined across the genomes analyzed. The nuclear genomes had extensive heterozygosity, and all samples existed as genetic mosaics with either -like or -like inheritance patterns supporting a highly interbred species genetic complex. As no barriers appear to exist for anthroponotic transmission of these 'hybrid' worms, a one-health approach to control the spread of human ascariasis will be necessary.
Topics: Animals; Ascariasis; Ascaris lumbricoides; Ascaris suum; Cyclooxygenase 1; Female; Genome, Helminth; Genome, Mitochondrial; Heterozygote; Humans; Hybridization, Genetic; Kenya; Male; Phylogeny; Polymorphism, Single Nucleotide; Proteome; Swine; Swine Diseases
PubMed: 33155980
DOI: 10.7554/eLife.61562 -
PLoS Neglected Tropical Diseases Jan 2017The benzimidazole (BZ) anthelmintics, albendazole (ABZ) and mebendazole (MBZ) are the most common drugs used for treatment of soil-transmitted helminths (STHs). Their...
BACKGROUND
The benzimidazole (BZ) anthelmintics, albendazole (ABZ) and mebendazole (MBZ) are the most common drugs used for treatment of soil-transmitted helminths (STHs). Their intensive use increases the possibility that BZ resistance may develop. In veterinary nematodes, BZ resistance is caused by a single nucleotide polymorphism (SNP) in the β-tubulin isotype 1 gene at codon position 200, 167 or 198, and these SNPs have also been correlated with poor response of human Trichuris trichiura to BZ treatment. It is important to be able to investigate the presence of resistance-associated SNPs in STHs before resistance becomes clinically established.
METHODS
The objective of this study was to develop new genotyping assays to screen for the presence of β-tubulin SNPs in T. trichiura and Ascaris lumbricoides. Rapid, simple and accurate genotyping assays were developed based on the SmartAmp2 method. Primer sets were optimized and selected to distinguish the SNP-variant genotypes. After initial optimization on control plasmids, the feasibility of the assay was assessed in field samples from Haiti and Panama. Finally, spiked fecal samples were assessed to determine the tolerance of Aac polymerase to fecal inhibitors.
FINDINGS
Rapid SNP genotyping assays were developed to target β-tubulin polymorphisms in T. trichiura and A. lumbricoides. The assays showed high sensitivity and specificity in field samples and also demonstrated high tolerance to PCR inhibitors in fecal samples.
CONCLUSION
These assays proved to be robust and efficient with the potential to be used as field tools for monitoring SNPs that could be associated with BZ resistance. However, further work is needed to validate the assays on large numbers of field samples before and after treatment.
Topics: Animals; Ascariasis; Ascaris lumbricoides; Feces; Genotype; Genotyping Techniques; Helminth Proteins; Humans; Polymorphism, Single Nucleotide; Trichuris; Tubulin
PubMed: 28081124
DOI: 10.1371/journal.pntd.0005205 -
BMC Public Health Feb 2017Understanding the prevalence of soil-transmitted helminth infections is necessary to plan control strategies and focus on highly endemic regions for preventive... (Review)
Review
BACKGROUND
Understanding the prevalence of soil-transmitted helminth infections is necessary to plan control strategies and focus on highly endemic regions for preventive chemotherapy and improved sanitation facilities. India is known to be endemic for soil-transmitted helminth infections.
METHODS
To understand the prevalence, spatial distribution and identify high-risk zones, a systematic search of published literature was carried out based on PRISMA guidelines from the year 2000 to 2015.
RESULTS
A careful screening of the identified literature yielded 39 studies that reported the prevalence of soil-transmitted helminth infections from 19 different states of India. Ascaris lumbricoides was the most prevalent parasite. Higher than 50% prevalence was reported from six states. Nearly 90% studies reported the prevalence of more than one parasite species in the same sample population.
CONCLUSION
This is the first study to comprehensively review the literature associated with soil-transmitted helminth infections from India giving a clear idea of its prevalence, distribution and high endemic areas.
Topics: Animals; Ascaris lumbricoides; Feces; Helminthiasis; Humans; India; Prevalence; Risk; Risk Factors; Soil; Spatial Analysis
PubMed: 28209148
DOI: 10.1186/s12889-017-4113-2 -
The Journal of Parasitology Jun 1998Ascaris lumbricoides worm counts were examined as the outcome products of exposure proxy variables. A survey of 663 children, 4-10 yr old, living in southeastern...
Ascaris lumbricoides worm counts were examined as the outcome products of exposure proxy variables. A survey of 663 children, 4-10 yr old, living in southeastern Madagascar revealed prevalences of 93% for A. lumbricoides, 55% for Trichuris trichiura, and 27% for hookworm. Worm expulsions were conducted on 428 of these children; the data revealed an overdispersed distribution of A. lumbricoides, with an arithmetic mean of 19.2 worms per child. A concurrent socioeconomic household survey was conducted by visitation and interview. Exposure to infection was assessed by environmental, demographic, behavioral, and socioeconomic indicators. Ascaris lumbricoides aggregations were associated with gender, housing style, ethnicity, and agricultural factors. The results suggest that exposure and infection are ubiquitous in this child population, and that A. lumbricoides intensity is influenced by gender-related behavioral and environmental factors that contribute to exposure.
Topics: Animals; Antinematodal Agents; Ascariasis; Ascaris lumbricoides; Child; Child, Preschool; Drug Therapy, Combination; Educational Status; Feces; Female; Health Behavior; Housing; Humans; Madagascar; Male; Mebendazole; Prevalence; Pyrantel Pamoate; Risk Factors; Rural Population; Sanitation; Sex Factors; Social Class
PubMed: 9645843
DOI: No ID Found -
Journal of Helminthology Mar 2019Ascaris sp. is a soil-transmitted helminth (STH) significantly affecting the health of human and swine populations. Health inequities and poverty, with resulting...
Ascaris sp. is a soil-transmitted helminth (STH) significantly affecting the health of human and swine populations. Health inequities and poverty, with resulting deficiencies in water, sanitation and hygiene, are directly associated with Ascaris lumbricoides prevalence in humans. Resource constraints also lead to small-scale livestock production under unsanitary conditions. Free-ranging pigs, for instance, are exposed to a number of infectious agents, among which Ascaris suum is one of the most common. Under these conditions, close proximity between people and pigs can result in cross-contamination; that is, pigs harbouring human Ascaris and vice versa. Moreover, the potential interbreeding between these two Ascaris species has been demonstrated. The present study analysed Ascaris worms obtained from children and pigs in Honduras. Adult worms were collected from stool samples of children after pharmacological treatment, and from pigs' intestines after slaughter for commercial purposes at a local abattoir. A nuclear ribosomal internal transcribed spacer (ITS) region was amplified by polymerase chain reaction (PCR) and digested with a restriction enzyme in order to separate putative human- and pig-derived Ascaris isolates. PCR products were also sequenced, and cladograms were constructed. All parasites isolated from children showed the typical human-derived genotype of Ascaris, whereas 91% of parasites from pigs showed the expected pig-derived genotype. Cross-infections between hosts were not demonstrated in this study. Nine per cent of pig-derived worms showed a restriction band pattern highly suggestive of a hybrid human-pig Ascaris genotype. These results contribute to the understanding of ascariasis epidemiology and its zoonotic potential in a highly endemic region.
Topics: Animals; Ascariasis; Ascaris; Ascaris lumbricoides; Ascaris suum; Child; DNA, Helminth; DNA, Ribosomal Spacer; Feces; Genotype; Honduras; Humans; Phylogeny; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Sequence Analysis, DNA; Swine; Swine Diseases; Zoonoses
PubMed: 29502555
DOI: 10.1017/S0022149X18000160