Evidence map›Paper›PMID 34563247›Full record

ArticleParasites & vectors2021

Improving stool sample processing and pyrosequencing for quantifying benzimidazole resistance alleles in Trichuris trichiura and Necator americanus pooled eggs.

Javier Gandasegui, Berta Grau-Pujol, María Cambra-Pelleja, Valdemiro Escola, Maria Antonietta Demontis, Anelsio Cossa, José Carlos Jamine, Rafael Balaña-Fouce, Lisette van Lieshout, José Muñoz and 2 more

Open access · goldAbstract readEvaluation Study
In one paragraph

Article in Parasites & vectors, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed, 1 pooled it
1.2field-weighted citation impact, top 24% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed, 1 synthesis or guideline pooled it, 8 citations in OpenAlex.

  1. Pooled it
  2. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

12 authors at 6 institutions in 4 countries.

Javier GandaseguiInstituto de Ganadería de Montaña (CSIC-Universidad de León), Grulleros, León, Spain.
Berta Grau-PujolISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.
María Cambra-PellejaInstituto de Ganadería de Montaña (CSIC-Universidad de León), Grulleros, León, Spain.
Valdemiro EscolaCentro de Investigação Em Saúde de Manhiça (CISM), Maputo, Mozambique.
Maria Antonietta DemontisDepartement of Parasitology, Leiden University Medical Center, Leiden, The Netherlands.
Anelsio CossaCentro de Investigação Em Saúde de Manhiça (CISM), Maputo, Mozambique.
José Carlos JamineCentro de Investigação Em Saúde de Manhiça (CISM), Maputo, Mozambique.
Rafael Balaña-FouceDepartamento de Ciencias Biomédicas, Universidad de León, León, Spain.
Lisette van LieshoutDepartement of Parasitology, Leiden University Medical Center, Leiden, The Netherlands.
José MuñozISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.
María Martínez-ValladaresInstituto de Ganadería de Montaña (CSIC-Universidad de León), Grulleros, León, Spain. mmarva@unileon.es.ORCID http://orcid.org/0000-0002-3723-1895
Stopping Transmission of Intestinal Parasites (STOP) Project Consortium
Instituto de Ganadería de Montaña · ESManhiça Health Research Centre · MZLeiden University Medical Center · NLBarcelona Institute for Global Health · ESFundación Pro Salud y Medio Ambiente · ARUniversidad de León · ES

Funding

Consejería de Educación, Junta de Castilla y León LE-135-19European and Developing Countries Clinical Trials Partnership RIA2017NCT-1845-STOPMinisterio de Economía y Competitividad FJC-2018-38305Ministerio de Economía y Competitividad RYC-2015-18368
6 · The paper itself

Abstract

backgroundThere is an urgent need for an extensive evaluation of benzimidazole efficacy in humans. In veterinary science, benzimidazole resistance has been mainly associated with three single-nucleotide polymorphisms (SNPs) in the isotype-1 β-tubulin gene. In this study, we optimized the stool sample processing methodology and resistance allele frequency assessment in Trichuris trichiura and Necator americanus anthelmintic-related SNPs by pyrosequencing, and standardized it for large-scale benzimidazole efficacy screening use.

methodsThree different protocols for stool sample processing were compared in 19 T. trichiura-positive samples: fresh stool, egg concentration using metallic sieves with decreasing pore size, and egg concentration followed by flotation with saturated salt solution. Yield of each protocol was assessed by estimating the load of parasite DNA by real-time PCR. Then, we sequenced a DNA fragment of the β-tubulin gene containing the putative benzimidazole resistance SNPs in T. trichiura and N. americanus. Afterwards, resistant and susceptible-type plasmids were produced and mixed at different proportions, simulating different resistance levels. These mixtures were used to compare previously described pyrosequencing assays with processes newly designed by our own group. Once the stool sample processing and the pyrosequencing methodology was defined, the utility of the protocols was assessed by measuring the frequencies of putative resistance SNPs in 15 T. trichiura- and 15 N. americanus-positive stool samples.

resultsThe highest DNA load was provided by egg concentration using metallic sieves with decreasing pore size. Sequencing information of the β-tubulin gene in Mozambican specimens was highly similar to the sequences previously reported, for T. trichiura and N. americanus, despite the origin of the sample. When we compared pyrosequencing assays using plasmids constructs, primers designed in this study provided the most accurate SNP frequencies. When pooled egg samples were analysed, none of resistant SNPs were observed in T. trichiura, whereas 17% of the resistant SNPs at codon 198 were found in one N. americanus sample.

conclusionsWe optimized the sample processing methodology and standardized pyrosequencing in soil-transmitted helminth (STH) pooled eggs. These protocols could be used in STH large-scale screenings or anthelmintic efficacy trials.

Indexed as

AllelesAnimalsAnthelminticsBenzimidazolesDNA PrimersDrug ResistanceFecesHigh-Throughput Nucleotide SequencingHumansNecator americanusOvumSoilSpecimen HandlingTrichurisAnthelminticsbenzimidazoleBenzimidazolesDNA PrimersSoilAnthelmintic resistanceBenzimidazolesPyrosequencingSoil-transmitted helminths

Identifiers

PMID34563247
PMCPMC8466976
OpenAlexW3203861882

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.