Morphological and genomic characterisation of the hybrid schistosome infecting humans in Europe reveals a complex admixture between Schistosoma haematobium and Schistosoma bovis parasites

AbstractSchistosomes cause schistosomiasis, the world’s second most important parasitic disease after malaria. A peculiar feature of schistosomes is their ability to produce viable and fertile hybrids. Originally only present in the tropics, schistosomiasis is now also endemic in Europe. Based on two genetic markers the European species had been identified as a hybrid between the ruminant-infective Schistosoma bovis and the human-infective Schistosoma haematobium.Here we describe for the first time the genomic composition of the European schistosome hybrid (77% of S. haematobium and 23% of S. bovis origins), its morphometric parameters and its compatibility with the European vector snail and intermediate host Compatibility is a key parameter for the parasites life cycle progression. We also show that egg morphology (a classical diagnostic parameter) does not allow for differential diagnosis while genetic tests do so. Additionally, we performed genome assembly improvement and annotation of S. bovis, the parental species for which no satisfactory genome assembly was available.For the first time since the discovery of hybrid schistosomes, these results reveal at the whole genomic level a complex admixture of parental genomes highlighting (i) the high permeability of schistosomes to other species’ alleles, and (ii) the importance of hybrid formation for pushing species boundaries not only conceptionally but also geographically.

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Morphological and genomic characterisation of the Schistosoma hybrid infecting humans in Europe reveals admixture between Schistosoma haematobium and Schistosoma bovis

PLoS Neglected Tropical Diseases ◽

10.1371/journal.pntd.0010062 ◽

2021 ◽

Vol 15 (12) ◽

pp. e0010062

Author(s):

Julien Kincaid-Smith ◽

Alan Tracey ◽

Ronaldo de Carvalho Augusto ◽

Ingo Bulla ◽

Nancy Holroyd ◽

...

Keyword(s):

Genome Assembly ◽

Schistosoma Haematobium ◽

Cycle Progression ◽

Bulinus Truncatus ◽

Schistosoma Bovis ◽

Long Read ◽

Egg Morphology ◽

Specific Species ◽

The Tropics ◽

Human Specific

Schistosomes cause schistosomiasis, the world’s second most important parasitic disease after malaria in terms of public health and social-economic impacts. A peculiar feature of these dioecious parasites is their ability to produce viable and fertile hybrid offspring. Originally only present in the tropics, schistosomiasis is now also endemic in southern Europe. Based on the analysis of two genetic markers the European schistosomes had previously been identified as hybrids between the livestock- and the human-infective species Schistosoma bovis and Schistosoma haematobium, respectively. Here, using PacBio long-read sequencing technology we performed genome assembly improvement and annotation of S. bovis, one of the parental species for which no satisfactory genome assembly was available. We then describe the whole genome introgression levels of the hybrid schistosomes, their morphometric parameters (eggs and adult worms) and their compatibility with two European snail strains used as vectors (Bulinus truncatus and Planorbarius metidjensis). Schistosome-snail compatibility is a key parameter for the parasites life cycle progression, and thus the capability of the parasite to establish in a given area. Our results show that this Schistosoma hybrid is strongly introgressed genetically, composed of 77% S. haematobium and 23% S. bovis origin. This genomic admixture suggests an ancient hybridization event and subsequent backcrosses with the human-specific species, S. haematobium, before its introduction in Corsica. We also show that egg morphology (commonly used as a species diagnostic) does not allow for accurate hybrid identification while genetic tests do.

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Hybridized Zoonotic Schistosoma Infections Result in Hybridized Morbidity Profiles: A Clinical Morbidity Study amongst Co-Infected Human Populations of Senegal

Microorganisms ◽

10.3390/microorganisms9081776 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1776

Author(s):

Cheikh B. Fall ◽

Sébastien Lambert ◽

Elsa Léger ◽

Lucy Yasenev ◽

Amadou Djirmay Garba ◽

...

Keyword(s):

Schistosoma Haematobium ◽

Monitoring And Evaluation ◽

Health Concern ◽

Human Populations ◽

Infectious Agents ◽

Schistosoma Bovis ◽

Control Programmes ◽

Potential Impact ◽

And Control ◽

First Time

Hybridization of infectious agents is a major emerging public and veterinary health concern at the interface of evolution, epidemiology, and control. Whilst evidence of the extent of hybridization amongst parasites is increasing, their impact on morbidity remains largely unknown. This may be predicted to be particularly pertinent where parasites of animals with contrasting pathogenicity viably hybridize with human parasites. Recent research has revealed that viable zoonotic hybrids between human urogenital Schistosoma haematobium with intestinal Schistosoma species of livestock, notably Schistosoma bovis, can be highly prevalent across Africa and beyond. Examining human populations in Senegal, we found increased hepatic but decreased urogenital morbidity, and reduced improvement following treatment with praziquantel, in those infected with zoonotic hybrids compared to non-hybrids. Our results have implications for effective monitoring and evaluation of control programmes, and demonstrate for the first time the potential impact of parasite hybridizations on host morbidity.

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Genetic Diversity of Basil (Ocimum spp. - Lamiaceae) Based on RAPD Markers and Volatile Oil Constituents

HortScience ◽

10.21273/hortsci.33.3.492f ◽

1998 ◽

Vol 33 (3) ◽

pp. 492f-493

Author(s):

Roberto F. Vieira ◽

James E. Simon ◽

Peter Goldsbrough ◽

Antonio Figueira

Keyword(s):

Genetic Diversity ◽

Molecular Markers ◽

Rapd Markers ◽

Volatile Oil ◽

Essential Oil Composition ◽

Oil Composition ◽

Traditional Medicines ◽

The Tropics ◽

High Degree ◽

First Time

Essential oils extracted from basil (Ocimum spp.) by steam distillation are used to flavor foods, oral products, in fragrances, and in traditional medicines. The genus Ocimum contains around 30 species native to the tropics and subtropics, with some species naturalized and/or cultivated in temperate areas. Interand intraspecific hybridization have created significant confusion in the botanical systematics of this genus. Taxonomy of basil (O. basilicum) is also complicated by the existence of numerous varieties, cultivars, and chemotypes within the species that do not differ significantly in morphology. In this study we are using RAPD markers and volatile oil composition to characterize the genetic diversity among the most economically important Ocimum species. We hypothesize that the genetic similarity revealed by molecular markers will more accurately reflect the morphological and chemical differences in Ocimum than essential oil composition per se. Preliminary research using five Ocimum species, four undetermined species, and eight varieties of O. basilicum (a total of 19 accessions) generated 107 polymorphic fragments amplified with 19 primers. RAPDs are able to discriminate between Ocimum species, but show a high degree of similarity between O. basilicum varieties. The genetic distance between nine species and among 55 accessions within the species O. americanum, O. basilicum, O. campechianum, O. × citriodorum, O. gratissimum, O. kilimandscharium, O. minimum, O. selloi, and O. tenuiflorum will be analyzed by matrix of similarity and compared to the volatile oil profile. This research will for the first time apply molecular markers to characterize the genetic diversity of Ocimum associate with volatile oil constituent.

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In the Labyrinth

10.1093/oso/9780198795155.003.0012 ◽

2017 ◽

Author(s):

Andrew McNeillie

Keyword(s):

The Right ◽

First Time ◽

Do So

It is now widely acknowledged, and far beyond Ireland, that Tim Robinson’s two volumes jointly known as Stones of Aran (‘Pilgrimage’ and ‘Labyrinth’) are modern classics, exemplary in every way of how to write about place and to do so with a formal, literary accomplishment that more than earns the right to nod at Ruskin’s own classic. In 2012, Robinson went back to Árainn, the largest of the three islands, for the first time in nearly ten years. He did so at the urging of Andrew McNeillie, with whom he spent two and a half days revisiting old haunts. This chapter makes account of the occasion and uses, in the process, a unique document provided by Robinson as an experiment in annotating his work. This prompts McNeillie to investigate some of his own annotations and footnotes to Aran.

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Big Questions in Ecology and Evolution

10.1093/oso/9780199548606.001.0001 ◽

2009 ◽

Cited By ~ 3

Author(s):

Thomas N. Sherratt ◽

David M. Wilkinson

Keyword(s):

Partial Solution ◽

Fundamental Importance ◽

Evolutionary Perspective ◽

Text Book ◽

Broad Audience ◽

The Future ◽

The Tropics ◽

Made In ◽

Do So

Why do we age? Why cooperate? Why do so many species engage in sex? Why do the tropics have so many species? When did humans start to affect world climate? This book provides an introduction to a range of fundamental questions that have taxed evolutionary biologists and ecologists for decades. Some of the phenomena discussed are, on first reflection, simply puzzling to understand from an evolutionary perspective, whilst others have direct implications for the future of the planet. All of the questions posed have at least a partial solution, all have seen exciting breakthroughs in recent years, yet many of the explanations continue to be hotly debated. Big Questions in Ecology and Evolution is a curiosity-driven book, written in an accessible way so as to appeal to a broad audience. It is very deliberately not a formal text book, but something designed to transmit the excitement and breadth of the field by discussing a number of major questions in ecology and evolution and how they have been answered. This is a book aimed at informing and inspiring anybody with an interest in ecology and evolution. It reveals to the reader the immense scope of the field, its fundamental importance, and the exciting breakthroughs that have been made in recent years.

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Reconstituting the International, 1918–1923

10.1093/oso/9780199641048.003.0003 ◽

2017 ◽

Author(s):

Talbot C. Imlay

Keyword(s):

Seismic Events ◽

Great War ◽

Bolshevik Revolution ◽

Meaning And Purpose ◽

Post War ◽

The Impact ◽

First Time ◽

The Great War ◽

Do So ◽

Lengthy Process

This chapter examines the post-war efforts of European socialists to reconstitute the Socialist International. Initial efforts to cooperate culminated in an international socialist conference in Berne in February 1919 at which socialists from the two wartime camps met for the first time. In the end, however, it would take four years to reconstitute the International with the creation of the Labour and Socialist International (LSI) in 1923. That it took so long to do so is a testimony to the impact of the Great War and to the Bolshevik revolution. Together, these two seismic events compelled socialists to reconsider the meaning and purpose of socialism. The search for answers sparked prolonged debates between and within the major parties, profoundly reconfiguring the pre-war world of European socialism. One prominent stake in this lengthy process, moreover, was the nature of socialist internationalism—both its content and its functioning.

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Breast Cancer Cell Re-Dissemination from Lung Metastases—A Mechanism for Enhancing Metastatic Burden

Journal of Clinical Medicine ◽

10.3390/jcm10112340 ◽

2021 ◽

Vol 10 (11) ◽

pp. 2340

Author(s):

Lucia Borriello ◽

John Condeelis ◽

David Entenberg ◽

Maja H. Oktay

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Cancer Cell ◽

Metastatic Disease ◽

Breast Cancer Cells ◽

Lung Metastases ◽

Primary Tumors ◽

Metastatic Burden ◽

First Time ◽

Do So

Although metastatic disease is the primary cause of mortality in cancer patients, the mechanisms leading to overwhelming metastatic burden are still incompletely understood. Metastases are the endpoint of a series of multi-step events involving cancer cell intravasation, dissemination to distant organs, and outgrowth to metastatic colonies. Here we show, for the first-time, that breast cancer cells do not solely disseminate to distant organs from primary tumors and metastatic nodules in the lymph nodes, but also do so from lung metastases. Thus, our findings indicate that metastatic dissemination could continue even after the removal of the primary tumor. Provided that the re-disseminated cancer cells initiate growth upon arrival to distant sites, cancer cell re-dissemination from metastatic foci could be one of the crucial mechanisms leading to overt metastases and patient demise. Therefore, the development of new therapeutic strategies to block cancer cell re-dissemination would be crucial to improving survival of patients with metastatic disease.

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Mastomys natalensis (Smith, 1834) as a natural host for Schistosoma haematobium (Bilharz, 1852) Weinland, 1858 x Schistosoma bovis Sonsino, 1876 introgressive hybrids

Parasitology Research ◽

10.1007/s00436-021-07099-7 ◽

2021 ◽

Author(s):

Boris A.E.S. Savassi ◽

Gauthier Dobigny ◽

Jonas R. Etougbétché ◽

Thalasse T. Avocegan ◽

François T. Quinsou ◽

...

Keyword(s):

Definitive Host ◽

Schistosoma Haematobium ◽

Rattus Rattus ◽

Introgressive Hybridization ◽

Mastomys Natalensis ◽

New Host ◽

Time Period ◽

Schistosoma Bovis ◽

Bulinus Globosus ◽

Internal Transcribed Spacer Rdna

AbstractCercarial emission of schistosomes is a determinant in the transmission to the definitive host and constitutes a good marker to identify which definitive host is responsible for transmission, mainly in introgressive hybridization situations. Our goal was to test the hypothesis that micro-mammals play a role in Schistosoma haematobium, S. bovis, and/or S. haematobium x S. bovis transmission. Small mammal sampling was conducted in seven semi-lacustrine villages of southern Benin. Among the 62 animals trapped, 50 individuals were investigated for Schistosoma adults and eggs: 37 Rattus rattus, 3 Rattus norvegicus, 9 Mastomys natalensis, and 1 Crocidura olivieri. Schistosoma adults were found in four R. rattus and two M. natalensis, with a local prevalence reaching 80% and 50%, respectively. Two cercarial chronotypes were found from Bulinus globosus experimentally infected with miracidia extracted from naturally infected M. natalensis: a late diurnal and nocturnal chronotype, and an early diurnal, late diurnal, and nocturnal chronotype. The cytochrome C oxidase subunit I mtDNA gene of the collected schistosomes (adults, miracidia, and cercariae) belonged to the S. bovis clade. Eleven internal transcribed spacer rDNA profiles were found; four belonged to S. bovis and seven to S. haematobium x S. bovis. These molecular results together with the observed multi-peak chronotypes add M. natalensis as a new host implicated in S. haematobium x S. bovis transmission. We discuss the origin of the new chronotypes which have become more complex with the appearance of several peaks in a 24-h day. We also discuss how the new populations of offspring may optimize intra-host ecological niche, host spectrum, and transmission time period.

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Quantifying the Impact of Production Globalization through Application of the Life Cycle Inventory Methodology and Its Influence on Decision Making in Industry

Processes ◽

10.3390/pr9081271 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1271

Author(s):

Humberto. J. Prado-Galiñanes ◽

Rosario Domingo

Keyword(s):

Decision Making ◽

Carbon Footprint ◽

Chain Model ◽

Fundamental Factor ◽

Supply Chain Model ◽

The Social ◽

The Impact ◽

A Company ◽

Key Parameter ◽

Do So

Industries are nowadays not only expected to produce goods and provide services, but also to do this sustainably. What qualifies a company as sustainable implies that its activities must be defined according to the social and ecological responsibilities that are meant to protect the society and the environment in which they operate. From now on, it will be necessary to consider and measure the impact of industrial activities on the environment, and to do so, one key parameter is the carbon footprint. This paper demonstrates the utility of the LCI as a tool for immediate application in industries. Its application shall facilitate decision making in industries while choosing amongst different scenarios to industrialize a certain product with the lowest environmental impact possible. To achieve this, the carbon footprint of a given product was calculated by applying the LCI method to several scenarios that differed from each other only in the supply-chain model. As a result of this LCI calculation, the impact of the globalization of a good’s production was quantified not only financially, but also environmentally. Finally, it was concluded that the LCI/LCA methodology can be considered as a fundamental factor in the new decision-making strategy that sustainable companies must implement while deciding on the business and industrial plan for their new products and services.

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Some Palaeoliths from South Arabia

Proceedings of the Prehistoric Society ◽

10.1017/s0079497x00017953 ◽

1954 ◽

Vol 19 (2) ◽

pp. 189-218 ◽

Cited By ~ 16

Author(s):

G. Caton-Thompson

Keyword(s):

Geographical Society ◽

South Arabia ◽

First Time ◽

Do So

The material here described was found in the Hadhramaut by Elinor Gardner and myself between November 1937 and March 1938. My personal investigation of the Palaeolithic Age was limited by pre-Islamic excavations, and I am therefore indebted to her for the gathering of most of the specimens in situ in terrace gravels, and to her detailed study of their positions.The collection consists mainly of groups from four fairly widely separated localities; the physiography of these has already been outlined in a comprehensive paper published in the Geographical Journal. Whenever appropriate to the purpose of this account, which is to place for the first time on illustrated record all we observed about the palaeoliths, I have reused in this different context illustrations of Quaternary environment which appeared in that Journal. With thanks I acknowledge the permission of the Royal Geographical Society to do so.

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