Alteration of host gene and protein expression by manipulative parasites.

Host manipulation mechanisms remain poorly understood. We summarize recent studies using -omics approaches (transcriptomics, proteomics) to explore alteration in gene expression in hosts infected by manipulative parasites. To guide future research, we highlight the common pattern of neuromodulation, as well as other diverse combinations of functions targeted across different host manipulation systems.

Invasion of the four kingdoms: the parasite journey across plant and non-plant hosts.

Parasites have a rich and long natural history among biological entities, and it has been suggested that parasites are one of the most significant factors in the evolution of their hosts. However, it has been emphasized less frequently how co-evolution has undoubtedly also shaped the paths of parasites. It may seem safe to assume that specific differences among the array of potential hosts for particular parasites have restricted and diversified their evolutionary pathways and strategies for survival.

Evolution of parasitological knowledge: can the past inform the future?

The growth of scientific knowledge is often likened to the evolution and diversification of life: new disciplines branch off older ones, and subsequently prosper or decline in a manner reminiscent of the expansion or extinction of diverse lineages of organisms. Based on a parallel between evolutionary diversification and knowledge growth, I examine the expansion of subdisciplines within 'ecological and evolutionary parasitology'. Bibliometric data are used to map the rise and fall of subdisciplines over time, capturing historical trends over the past several decades.

Universal versus taxon-specific drivers of helminth prevalence and intensity of infection.

Two key epidemiological parameters, prevalence and mean intensity of infection, together capture the abundance of macroparasite populations, the strength of density-dependent effects they experience, their potential impact on host population dynamics and the selective pressures they exert on their hosts. Yet, the drivers of the extensive variation observed in prevalence and mean intensity of infection, even among related parasite taxa infecting related hosts, remain mostly unknown. We performed phylogenetically grounded Bayesian modelling across hundreds of amphibian populations to test the effects of various predictors of prevalence and intensity of infection by six families of helminth parasites.

What shapes a microbiome? Differences in bacterial communities associated with helminth-amphipod interactions.

The fast technological advances of molecular tools have enabled us to uncover a new dimension hidden within parasites and their hosts: their microbiomes. Increasingly, parasitologists characterise host microbiome changes in the face of parasitic infections, revealing the potential of these microscopic fast-evolving entities to influence host-parasite interactions. However, most of the changes in host microbiomes seem to depend on the host and parasite species in question.

Microbial artists: the role of parasite microbiomes in explaining colour polymorphism among amphipods and potential link to host manipulation.

Parasite infections are increasingly reported to change the microbiome of the parasitized hosts, while parasites bring their own microbes to what can be a multi-dimensional interaction. For instance, a recent hypothesis suggests that the microbial communities harboured by parasites may play a role in the well-documented ability of many parasites to manipulate host phenotype, and explain why the degree to which host phenotype is altered varies among conspecific parasites. Here, we explored whether the microbiomes of both hosts and parasites are associated with variation in host manipulation by parasites.

Evolution of parasites in the Anthropocene: new pressures, new adaptive directions.

The Anthropocene is seeing the human footprint rapidly spreading to all of Earth's ecosystems. The fast-changing biotic and abiotic conditions experienced by all organisms are exerting new and strong selective pressures, and there is a growing list of examples of human-induced evolution in response to anthropogenic impacts. No organism is exempt from these novel selective pressures.

Nomenclatural stability and the longevity of helminth species names.

Although most Latin binomial names of species are valid, many are eventually unaccepted when they are found to be synonyms of previously described species, or superseded by a new combination when the species they denote are moved to a different genus. What proportion of parasite species names become unaccepted over time, and how long does it take for incorrect names to become unaccepted? Here, we address these questions using a dataset comprising thousands of species names of parasitic helminths from four higher taxa (Acanthocephala, Nematoda, Cestoda, and Trematoda). Overall, among species names proposed in the past two-and-a-half centuries, nearly one-third have since been unaccepted, the most common reason being that they have been superseded by a new combination.

Precursor-Directed Biosynthesis of Antialgal Fluorinated Bacillamide Derivatives in .

The bacillamides are a class of indole alkaloids produced by the genus that possess significant antialgal activity. Incorporation of fluorine into the bacillamides was carried out using a precursor-directed biosynthesis approach, with 4-, 5-, and 6-fluorotryptophan added to growing cultures of IMG-11. This yielded the corresponding fluorinated analogues of bacillamides A and C, in addition to new derivatives of the related metabolite -acetyltryptamine, thus demonstrating a degree of plasticity in the bacillamide biosynthetic pathway.

Genome assembly and annotation of the mermithid nematode Mermis nigrescens.

Genetic studies of nematodes have been dominated by Caenorhabditis elegans as a model species. A lack of genomic resources has limited the expansion of genetic research to other groups of nematodes. Here, we report a draft genome assembly of a mermithid nematode, Mermis nigrescens.

A position statement on the post gene-therapy rehabilitation of aromatic I-amino acid decarboxylase deficiency patients.

Aromatic L-amino acid decarboxylase (AADC) deficiency is a rare genetic disorder of monoamine neurotransmitter synthesis that presents with a range of symptoms, including motor dysfunction and limited attainment of developmental motor milestones. The approval of eladocagene exuparvovec, a gene therapy for AADC deficiency with demonstrated efficacy for motor improvements, now expands the range of motor outcomes possible for patients with this disorder. However, recommendations and guidelines for therapy following treatment with gene therapy are lacking.

Gait pattern analysis before and after periacetabular osteotomy in unilaterally affected dysplastic patients.

Background: Patients with acetabular dysplasia have an abnormal acetabular geometry which results in insufficient coverage of the femoral head. This coverage deficiency reduces contact surfaces within the joint, accelerating the wear of the articular cartilage and predisposing patients to early osteoarthritis. Periacetabular osteotomy is a surgical treatment of acetabular dysplasia that aims to reorient the acetabulum relative to the femoral head, increasing coverage.

Trematode genetic patterns at host individual and population scales provide insights about infection mechanisms.

Multiple parasites can infect a single host, creating a dynamic environment where each parasite must compete over host resources. Such interactions can cause greater harm to the host than single infections and can also have negative consequences for the parasites themselves. In their first intermediate hosts, trematodes multiply asexually and can eventually reach up to 20% of the host's biomass.

Vector species richness predicts local mortality rates from Chagas disease.

Vector species richness may drive the prevalence of vector-borne diseases by influencing pathogen transmission rates. The dilution effect hypothesis predicts that higher biodiversity reduces disease prevalence, but with inconclusive evidence. In contrast, the amplification effect hypothesis suggests that higher vector diversity may result in greater disease transmission by increasing and diversifying the transmission pathways.

Transcriptomics-guided identification of an algicidal protease of the marine bacterium Kordia algicida OT-1.

In recent years, interest in algicidal bacteria has risen due to their ecological importance and their potential as biotic regulators of harmful algal blooms. Algicidal bacteria shape the plankton communities of the oceans by inhibiting or lysing microalgae and by consuming the released nutrients. Kordia algicida strain OT-1 is a model marine algicidal bacterium that was isolated from a bloom of the diatom Skeletonema costatum.

Model worms: knowledge gains and risks associated with the use of model species in parasitological research.

Model parasite species, whose entire life cycle can be completed in the laboratory and maintained for multiple generations, have played a fundamental role in our understanding of host–parasite interactions. Yet, keeping parasites in laboratory conditions may expose them to unnatural evolutionary pressures, and using laboratory cultures for research is therefore not without limitations. Using 2 widely-used model helminth species, the cestode and the nematode , I illustrate the caution needed when interpreting experimental results on model species.

Light pollution may alter host-parasite interactions in aquatic ecosystems.

With growing human populations living along freshwater shores and marine coastlines, aquatic ecosystems are experiencing rising levels of light pollution. Through its effects on hosts and parasites, anthropogenic light at night can disrupt host-parasite interactions evolved under a normal photoperiod. Yet its impact on aquatic parasites has been ignored to date.

"There are still broken or fragmented systems": Qualitative assessment of needs to strengthen adolescent mental health services in American Samoa.

Mental health challenges appear common among adolescents in American Samoa. There is a community-identified need to better understand the health burden and identify opportunities to strengthen the mental health system to better meet adolescent mental health needs. The goal of this qualitative study was to gather community stakeholders' perceptions of common mental health problems among adolescents in American Samoa, identify existing services for adolescent mental health, and highlight strength-based opportunities to enhance care.

Different trematode parasites in the same snail host: Species-specific or shared microbiota?

The concept that microbes associated with macroorganisms evolve as a unit has swept evolutionary ecology. However, this idea is controversial due to factors such as imperfect vertical transmission of microbial lineages and high microbiome variability among conspecific individuals of the same population. Here, we tested several predictions regarding the microbiota of four trematodes (Galactosomum otepotiense, Philophthalmus attenuatus, Acanthoparyphium sp.

Interrelationships and properties of parasite aggregation measures: a user's guide.

Aggregation of macroparasites among hosts is nearly universal among parasite-host associations. Researchers testing hypotheses on origins of parasite aggregation and its importance to parasite and host population ecology have used different measures of aggregation that are not necessarily measuring the same thing, potentially clouding our understanding of underlying epidemiological processes. We highlight these differences in meanings by exploring properties and interrelationships of six common measures of parasite aggregation, and provide a "user's guide" to inform researchers' decisions regarding their application.

Global analysis of seasonal changes in trematode infection levels reveals weak and variable link to temperature.

Seasonal changes in environmental conditions drive phenology, i.e., the annual timing of biological events ranging from the individual to the ecosystem.

Adoption of alternative life cycles in a parasitic trematode is linked to microbiome differences.

For parasites with complex multi-host life cycles, the facultative truncation of the cycle represents an adaptation to challenging conditions for transmission. However, why certain individuals are capable of abbreviating their life cycle while other conspecifics are not remains poorly understood. Here, we test whether conspecific trematodes that either follow the normal three-host life cycle or skip their final host by reproducing precociously (via progenesis) in an intermediate host differ in the composition of their microbiomes.

Gender Discrimination and Mental Health Among Health Care Workers: Findings from a Mixed Methods Study.

Gender discrimination among healthcare workers (HCWs) negatively impacts their mental health and career development; however, few studies have explored how experiences of gender discrimination change during times of health system strain. This survey-based study assesses the associations between gender discrimination and four stress-related mental health outcomes (posttraumatic stress, depression, anxiety, and burnout), as well as the qualitative experiences of gender discrimination in healthcare during the COVID-19 pandemic. Among women, increased gender discrimination was associated with heightened symptoms of posttraumatic stress, depression, anxiety, and burnout after adjusting for demographics and pandemic-related stressors; however, among men, increased gender discrimination was only associated with heightened symptoms of depression.

Physical evidence of direct antagonistic interactions between trematodes in the host gut: the kiss of death?

Although within-host competition among parasites if often assumed to occur based on statistical patterns, actual physical evidence of direct antagonistic interactions between parasites, either intraspecific or interspecific, is very rare. Here, we report such evidence between and within two species of hemiurid trematodes infecting the deep-sea grenadier fish Coryphaenoides subserrulatus. We found pairs of worms attached together, with one worm using its ventral sucker against another worm, and sucking out a large protuberance on the victim.