Articoli di riviste: "Host-parasite relationships"

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McPartland, John M., e Karl W. Hillig. "Host-Parasite Relationships inCannabis". Journal of Industrial Hemp 10, n. 2 (4 gennaio 2006): 85–104. http://dx.doi.org/10.1300/j237v10n02_08.

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Beaman, B. L., e L. Beaman. "Nocardia species: host-parasite relationships." Clinical Microbiology Reviews 7, n. 2 (aprile 1994): 213–64. http://dx.doi.org/10.1128/cmr.7.2.213.

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The nocardiae are bacteria belonging to the aerobic actinomycetes. They are an important part of the normal soil microflora worldwide. The type species, Nocardia asteroides, and N. brasiliensis, N. farcinica, N. otitidiscaviarum, N. nova, and N. transvalensis cause a variety of diseases in both normal and immunocompromised humans and animals. The mechanisms of pathogenesis are complex, not fully understood, and include the capacity to evade or neutralize the myriad microbicidal activities of the host. The relative virulence of N. asteroides correlates with the ability to inhibit phagosome-lysosome fusion in phagocytes; to neutralize phagosomal acidification; to detoxify the microbicidal products of oxidative metabolism; to modify phagocyte function; to grow within phagocytic cells; and to attach to, penetrate, and grow within host cells. Both activated macrophages and immunologically specific T lymphocytes constitute the major mechanisms for host resistance to nocardial infection, whereas B lymphocytes and humoral immunity do not appear to be as important in protecting the host. Thus, the nocardiae are facultative intracellular pathogens that can persist within the host, probably in a cryptic form (L-form), for life. Silent invasion of brain cells by some Nocardia strains can induce neurodegeneration in experimental animals; however, the role of nocardiae in neurodegenerative diseases in humans needs to be investigated.

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Beaman, B. L., e L. Beaman. "Nocardia species: host-parasite relationships." Clinical Microbiology Reviews 7, n. 2 (1994): 213–64. http://dx.doi.org/10.1128/cmr.7.2.213-264.1994.

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Calderone, R. A. "Host-Parasite Relationships in Candidosis". Mycoses 32 (24 aprile 2009): 12–17. http://dx.doi.org/10.1111/j.1439-0507.1989.tb02303.x.

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Franco, M. "Host-parasite relationships in paracoccidioidomycosis". Medical Mycology 25, n. 1 (gennaio 1987): 5–18. http://dx.doi.org/10.1080/02681218780000021.

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Blair, John E. "HOST-PARASITE RELATIONSHIPS: A SUMMATION". Annals of the New York Academy of Sciences 128, n. 1 (16 dicembre 2006): 451–56. http://dx.doi.org/10.1111/j.1749-6632.1965.tb11654.x.

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Solomon, N., I. James, N. Alphonsus e R. Nkiruka. "A Review of Host-Parasite Relationships". Annual Research & Review in Biology 5, n. 5 (10 gennaio 2015): 372–84. http://dx.doi.org/10.9734/arrb/2015/10263.

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Roberts, James A., George M. Suarez, Bernice Kaack, Gerald J. Domingue e Stefan B. Svenson. "Host-Parasite Relationships in Acute Pyelonephritis". American Journal of Kidney Diseases 8, n. 3 (settembre 1986): 139–45. http://dx.doi.org/10.1016/s0272-6386(86)80016-6.

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Salzet, M., A. Capron e G. B. Stefano. "Molecular Crosstalk in Host–Parasite Relationships:". Parasitology Today 16, n. 12 (dicembre 2000): 536–40. http://dx.doi.org/10.1016/s0169-4758(00)01787-7.

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Duff, Gordon W., e Joost J. Oppenheim. "Comparative aspects of host-parasite and host-tumor relationships". Cytokine 4, n. 5 (settembre 1992): 331–39. http://dx.doi.org/10.1016/1043-4666(92)90075-3.

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Tellier, Aurélien, e James K. M. Brown. "The Relationship of Host-Mediated Induced Resistance to Polymorphism in Gene-for-Gene Relationships". Phytopathology® 98, n. 1 (gennaio 2008): 128–36. http://dx.doi.org/10.1094/phyto-98-1-0128.

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Gene-for-gene relationships are a common feature of plant-parasite interactions. Polymorphism at host resistance and parasite avirulence loci is maintained if there is negative, direct frequency-dependent selection on alleles of either gene. More specifically, selection of this kind is generated when the disease is polycyclic with frequent auto-infection. When an incompatible interaction occurs between a resistant host and an avirulent parasite, systemic defenses are triggered, rendering the plant more resistant to a later attack by another parasite. However, induced resistance (IR) incurs a fitness cost to the plant. Here, the effect of IR on polymorphism in gene-for-gene interactions is investigated. First, in an infinite population model in which parasites have two generations per host generation, increasing the fitness cost of IR increases selection for susceptible plants at low disease severity, while increasing the effectiveness of IR against further parasite attacks enhances selection for resistant plants at high disease severity. This reduces the possibility of polymorphism being maintained in host and parasite populations. In finite population models, the number of plants varies over time as a function of the disease burden of the population. Polymorphism in gene-for-gene relationships is then more stable at high disease prevalence and severity if IR reactions are more costly when there is competition for resources between plants.

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Petri, W. A., C. G. Clark e L. S. Diamond. "Host-Parasite Relationships in Amebiasis: Conference Report". Journal of Infectious Diseases 169, n. 3 (1 marzo 1994): 483–84. http://dx.doi.org/10.1093/infdis/169.3.483.

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Justine, J. L., e M. C. Durette-Desset. "Evolution of Parasites and Host–Parasite Relationships". Parasitology Today 16, n. 8 (agosto 2000): 315. http://dx.doi.org/10.1016/s0169-4758(00)01725-7.

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Beckage, Nancy E. "Host-parasite hormonal relationships: A common theme?" Experimental Parasitology 72, n. 3 (aprile 1991): 332–38. http://dx.doi.org/10.1016/0014-4894(91)90153-n.

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Strona, Giovanni, e Simone Fattorini. "A Few Good Reasons Why Species-Area Relationships Do Not Work for Parasites". BioMed Research International 2014 (2014): 1–5. http://dx.doi.org/10.1155/2014/271680.

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Several studies failed to find strong relationships between the biological and ecological features of a host and the number of parasite species it harbours. In particular, host body size and geographical range are generally only weak predictors of parasite species richness, especially when host phylogeny and sampling effort are taken into account. These results, however, have been recently challenged by a meta-analytic study that suggested a prominent role of host body size and range extent in determining parasite species richness (species-area relationships). Here we argue that, in general, results from meta-analyses should not discourage researchers from investigating the reasons for the lack of clear patterns, thus proposing a few tentative explanations to the fact that species-area relationships are infrequent or at least difficult to be detected in most host-parasite systems. The peculiar structure of host-parasite networks, the enemy release hypothesis, the possible discrepancy between host and parasite ranges, and the evolutionary tendency of parasites towards specialization may explain why the observed patterns often do not fit those predicted by species-area relationships.

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Turner, Wendy C., Pauline L. Kamath, Henriette van Heerden, Yen-Hua Huang, Zoe R. Barandongo, Spencer A. Bruce e Kyrre Kausrud. "The roles of environmental variation and parasite survival in virulence–transmission relationships". Royal Society Open Science 8, n. 6 (giugno 2021): 210088. http://dx.doi.org/10.1098/rsos.210088.

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Disease outbreaks are a consequence of interactions among the three components of a host–parasite system: the infectious agent, the host and the environment. While virulence and transmission are widely investigated, most studies of parasite life-history trade-offs are conducted with theoretical models or tractable experimental systems where transmission is standardized and the environment controlled. Yet, biotic and abiotic environmental factors can strongly affect disease dynamics, and ultimately, host–parasite coevolution. Here, we review research on how environmental context alters virulence–transmission relationships, focusing on the off-host portion of the parasite life cycle, and how variation in parasite survival affects the evolution of virulence and transmission. We review three inter-related ‘approaches’ that have dominated the study of the evolution of virulence and transmission for different host–parasite systems: (i) evolutionary trade-off theory, (ii) parasite local adaptation and (iii) parasite phylodynamics. These approaches consider the role of the environment in virulence and transmission evolution from different angles, which entail different advantages and potential biases. We suggest improvements to how to investigate virulence–transmission relationships, through conceptual and methodological developments and taking environmental context into consideration. By combining developments in life-history evolution, phylogenetics, adaptive dynamics and comparative genomics, we can improve our understanding of virulence–transmission relationships across a diversity of host–parasite systems that have eluded experimental study of parasite life history.

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Courtney, Cheryl C., e Bruce M. Christensen. "Host-Parasite Relationships of Caryophyllaeid Cestodes and Aquatic Oligochaetes: I. Host Longevity and Parasite Intensity". Journal of Parasitology 73, n. 6 (dicembre 1987): 1124. http://dx.doi.org/10.2307/3282292.

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Bibik, Nacheva e Arkhipov. "MICROMORPHOLOGICAL PECULIARITIES OF RELATIONSHIPS IN THE “PARASIT-HOST” SYSTEM". THEORY AND PRACTICE OF PARASITIC DISEASE CONTROL, n. 20 (14 maggio 2019): 108–14. http://dx.doi.org/10.31016/978-5-9902340-8-6.2019.20.108-114.

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Micromorphological, histochemical and pathomorphological features of relationships in the “parasite-host” system before and after exposure to the antitremum (at a dose of 200 mg / kg of LW) and tegalide (at a dose of 30 mg / kg of LW) were studied in a comparative aspect using the example of parasitizing by a Paramphistomum cervi in sheep intestines. The effect of anthelmintics on trematodes is associated with endostation of the parasite, in which certain trophic links are formed between the host and the helminth. The adhesion in the morphofunctional complex “tegument-epithelial tissue of the intestinal villus” at paramphystomy of sheep is considered as an indicator of the maturity of the reciprocal relationship between the parasite and the host. Pathomorphological changes in the mucous membrane of the intestine of sheep with paramphystomy are characterized by the presence of proliferation, hyperplasia and metaplasia, which provide the dynamic stability of the parasite-host system in the endostation of the parasite. Pathomorphological manifestations in the small intestine of sheep with paramphystomy and chemotherapy with tehalide and antithyroid consist of alternative dystrophic and proliferative processes. With the introduction of anthelmintic into the host organism, a violation of the homeokinetic state of each of the biological species that make up this binary system occurs, which leads to destabilization and homeoclase, and then to the death of the system and the development of the disease with clinical manifestations.The micromorphological features of interrelations in the “parasite-host” system, studied with the example of parasitic Paramphistomum cervi in the intestine of spontaneously-infested sheep, before and after the anthelmintic effects of antitermite and tehalid reveal the mechanisms of morphofunctional interrelations in the process of transition of the “parasite-host” from the homeoresistive state to the homeoclasis one and allow you to assess the impact efficiency of anthelmintics with trematodoses.

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F. Meyer, S. L. "Host-Parasite Relationships BetweenPseudopeziza trifoliif. sp.medicaginis-sativaeand Alfalfa". Phytopathology 77, n. 2 (1987): 309. http://dx.doi.org/10.1094/phyto-77-309.

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Cashion, Norma L. "Host-Parasite Relationships in Karnal Bunt of Wheat". Phytopathology 78, n. 1 (1988): 75. http://dx.doi.org/10.1094/phyto-78-75.

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Mejia, J. Santiago, Fernando Moreno, Carlos Muskus, Iván D. Vélez e Richard G. Titus. "The surface–mosaic model in host–parasite relationships". Trends in Parasitology 20, n. 11 (novembre 2004): 508–11. http://dx.doi.org/10.1016/j.pt.2004.08.005.

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Douhan, Greg W., e David M. Rizzo. "Host-parasite relationships among bolete infecting Hypomyces species". Mycological Research 107, n. 11 (novembre 2003): 1342–49. http://dx.doi.org/10.1017/s0953756203008542.

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Di Vito, M., N. Vovlas e P. Castillo. "Host-parasite relationships of Meloidogyne incognita on spinach". Plant Pathology 53, n. 4 (agosto 2004): 508–14. http://dx.doi.org/10.1111/j.1365-3059.2004.01053.x.

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Eleftheriou, Andreas. "Relationships among host microbiota, parasite resistance or tolerance, and host fitness". Conservation Biology 34, n. 6 (18 settembre 2020): 1327–28. http://dx.doi.org/10.1111/cobi.13582.

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Kuchboev, A., N. E. Tarasovskaya, B. K. Zhumabekova e M. Yu Klimenko. "INTERSPECIFIC AND INTRASPECIFIC RELATIONSHIPS OF GREAT CORMORANT’S NEMATODE CONTRACAECUM RUDOLPHII IN PAVLODAR REGION". BIOLOGICAL SCIENCES OF KAZAKHSTAN 1 (15 marzo 2024): 15–26. http://dx.doi.org/10.52301/1684-940x-2024-1-15-26.

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The size of helminths is substantially influenced by interspecific interactions. There are around 90 copies present. The presence of Contracecums in the intestine of a single cormorant individual resulted in a significant reduction in the overall size of the nematodes. When cestodes are present, Contracecums undergo brachymorphic changes, which can be seen as an adaptation to maintain fertility while minimising energy expenditure. The ratio of parasite abundance in the host to parasite size might vary based on the specific parameters of the host-parasite interaction. The size of the parasite can be regulated by multiple factors associated with the parasite population within the host.

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Rodríguez, Sara M., e Nelson Valdivia. "Mesoscale spatiotemporal variability in a complex host-parasite system influenced by intermediate host body size". PeerJ 5 (17 agosto 2017): e3675. http://dx.doi.org/10.7717/peerj.3675.

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Background Parasites are essential components of natural communities, but the factors that generate skewed distributions of parasite occurrences and abundances across host populations are not well understood. Methods Here, we analyse at a seascape scale the spatiotemporal relationships of parasite exposure and host body-size with the proportion of infected hosts (i.e., prevalence) and aggregation of parasite burden across ca. 150 km of the coast and over 22 months. We predicted that the effects of parasite exposure on prevalence and aggregation are dependent on host body-sizes. We used an indirect host-parasite interaction in which migratory seagulls, sandy-shore molecrabs, and an acanthocephalan worm constitute the definitive hosts, intermediate hosts, and endoparasite, respectively. In such complex systems, increments in the abundance of definitive hosts imply increments in intermediate hosts’ exposure to the parasite’s dispersive stages. Results Linear mixed-effects models showed a significant, albeit highly variable, positive relationship between seagull density and prevalence. This relationship was stronger for small (cephalothorax length >15 mm) than large molecrabs (<15 mm). Independently of seagull density, large molecrabs carried significantly more parasites than small molecrabs. The analysis of the variance-to-mean ratio of per capita parasite burden showed no relationship between seagull density and mean parasite aggregation across host populations. However, the amount of unexplained variability in aggregation was strikingly higher in larger than smaller intermediate hosts. This unexplained variability was driven by a decrease in the mean-variance scaling in heavily infected large molecrabs. Conclusions These results show complex interdependencies between extrinsic and intrinsic population attributes on the structure of host-parasite interactions. We suggest that parasite accumulation—a characteristic of indirect host-parasite interactions—and subsequent increasing mortality rates over ontogeny underpin size-dependent host-parasite dynamics.

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Vinson, John E., e Andrew W. Park. "Vector-borne parasite invasion in communities across space and time". Proceedings of the Royal Society B: Biological Sciences 286, n. 1917 (18 dicembre 2019): 20192614. http://dx.doi.org/10.1098/rspb.2019.2614.

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While vector-borne parasite transmission often operates via generalist-feeding vectors facilitating cross-species transmission in host communities, theory describing the relationship between host species diversity and parasite invasion in these systems is underdeveloped. Host community composition and abundance vary across space and time, generating opportunities for parasite invasion. To explore how host community variation can modify parasite invasion potential, we develop a model for vector-borne parasite transmission dynamics that includes a host community of arbitrary richness and species' abundance. To compare invasion potential across communities, we calculate the community basic reproductive ratio of the parasite. We compare communities comprising a set of host species to their subsets, which allows for flexible scenario building including the introduction of novel host species and species loss. We allow vector abundance to scale with, or be independent of, community size, capturing regulation by feeding opportunities and non-host effects such as limited oviposition sites. Motivated by equivocal data relating host species competency to abundance, we characterize plausible host communities via phenomenological relationships between host species abundance and competency. We identify an underappreciated mechanism whereby changes to communities simultaneously alter average competency and the vector to host ratio and demonstrate that the interaction can profoundly influence invasion potential.

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Hanke, Marc H., Martin H. Posey e Troy D. Alphin. "Spatial Dynamics of Two Host-Parasite Relationships on Intertidal Oyster Reefs". Diversity 13, n. 6 (10 giugno 2021): 260. http://dx.doi.org/10.3390/d13060260.

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Intertidal reefs comprised of the eastern oyster (Crassostrea virginica) have long experienced habitat loss, altering habitat patch characteristics of size and distance from edge to interior, potentially influencing spatial dynamics of host-parasite relationships. Using two parasitic relationships, one between eastern oyster host and parasitic oyster pea crab (Zaops ostreum) and the other between a xanthid crab (Eurypanopeus depressus) and a parasitic rhizocephalan barnacle (Loxothylacus panopaei), we examined how host-parasite population characteristics varied on intertidal reefs by season, reef size, and distance from edge to interior. Pea crab prevalence was more related to habitat characteristics rather than host density, as pea crab prevalence was the highest on large reefs and along edges, areas of comparatively lower oyster densities. Reef size did not influence densities of parasitized or non-parasitized xanthid crabs, but densities varied from edge to interior. Non-parasitized xanthids had significantly lower densities along the reef edge compared to more interior reef locations, while parasitized xanthid crabs had no significant edge to interior pattern. Organismal size had a varied relationship based upon habitat characteristics, as pea crab carapace width (CW) varied interactively with season and reef size, whereas CW of parasitized/non-parasitized xanthid crabs varied significantly between edge and interior locations. These results demonstrated that influential habitat characteristics, such as patch size and edge versus interior, are both highly species and host-parasite specific. Therefore, continued habitat alteration and fragmentation of critical marine habitats may further impact spatial dynamics of host-parasite relationships.

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PATTERSON, JESSE E. H., e KATHREEN E. RUCKSTUHL. "Parasite infection and host group size: a meta-analytical review". Parasitology 140, n. 7 (21 febbraio 2013): 803–13. http://dx.doi.org/10.1017/s0031182012002259.

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SUMMARYMany studies have identified various host behavioural and ecological traits that are associated with parasite infection, including host gregariousness. By use of meta-analyses, we investigated to what degree parasite prevalence, intensity and species richness are correlated with group size in gregarious species. We predicted that larger groups would have more parasites and higher parasite species richness. We analysed a total of 70 correlations on parasite prevalence, intensity and species richness across different host group sizes. Parasite intensity and prevalence both increased positively with group size, as expected. No significant relationships were found between host group size and parasite species richness, suggesting that larger groups do not harbour more rare or novel parasite species than smaller groups. We further predicted that the mobility of the host (mobile, sedentary) and the mode of parasite transmission (direct, indirect, mobile) would be important predictors of the effects of group sizes on parasite infection. It was found that group size was positively correlated with the prevalence and intensity of directly and indirectly transmitted parasites. However, a negative relationship was observed between group size and mobile parasite intensity, with larger groups having lower parasite intensities. Further, intensities of parasites did not increase with group size of mobile hosts, suggesting that host mobility may negate parasite infection risk. The implications for the evolution and maintenance of sociality in host species are discussed, and future research directions are highlighted.

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Gillespie, Thomas R. "Book review: Primate Parasite Ecology: The Dynamics and Study of Host-Parasite Relationships". American Journal of Human Biology 22, n. 3 (1 febbraio 2010): 425–26. http://dx.doi.org/10.1002/ajhb.21035.

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Mbora, David N. M. "Book review: Primate Parasite Ecology: The Dynamics and Study of Host-Parasite Relationships". American Journal of Physical Anthropology 142, n. 3 (22 febbraio 2010): 503–4. http://dx.doi.org/10.1002/ajpa.21278.

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Lafferty, Kevin D. "Biodiversity loss decreases parasite diversity: theory and patterns". Philosophical Transactions of the Royal Society B: Biological Sciences 367, n. 1604 (19 ottobre 2012): 2814–27. http://dx.doi.org/10.1098/rstb.2012.0110.

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Past models have suggested host–parasite coextinction could lead to linear, or concave down relationships between free-living species richness and parasite richness. I explored several models for the relationship between parasite richness and biodiversity loss. Life cycle complexity, low generality of parasites and sensitivity of hosts reduced the robustness of parasite species to the loss of free-living species diversity. Food-web complexity and the ordering of extinctions altered these relationships in unpredictable ways. Each disassembly of a food web resulted in a unique relationship between parasite richness and the richness of free-living species, because the extinction trajectory of parasites was sensitive to the order of extinctions of free-living species. However, the average of many disassemblies tended to approximate an analytical model. Parasites of specialist hosts and hosts higher on food chains were more likely to go extinct in food-web models. Furthermore, correlated extinctions between hosts and parasites (e.g. if parasites share a host with a specialist predator) led to steeper declines in parasite richness with biodiversity loss. In empirical food webs with random removals of free-living species, the relationship between free-living species richness and parasite richness was, on average, quasi-linear, suggesting biodiversity loss reduces parasite diversity more than previously thought.

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CAMPBELL, JENNIFER, BETH KESSLER, CHRISTOPHER MAYACK e DHRUBA NAUG. "Behavioural fever in infected honeybees: parasitic manipulation or coincidental benefit?" Parasitology 137, n. 10 (26 maggio 2010): 1487–91. http://dx.doi.org/10.1017/s0031182010000235.

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SUMMARYInfection by a parasite often induces behavioural changes in the host and these changes may benefit either the host or the parasite. However, whether these changes are active host defence mechanisms or parasitic manipulations or simply incidental byproducts of the infection is not always clear. It has been suggested that understanding the proximate mechanisms of these changes as well as comparative studies could help distinguish these alternatives better. Behavioural fever is a common response to an infection in many animals and we investigated the phenomenon in the novel host-parasite relationship between the honeybee and the temperature-sensitive microsporidian Nosema ceranae. Our results show that infected bees prefer higher temperatures and even though this seems to benefit the pathogen, the proximate mechanism underlying this change is the pathological stress underlying the infection. Especially because it is a new host-parasite relationship, it is best to label the observed behavioural change as a case of incidental benefit although this does not rule out selection acting on it. We discuss the importance of looking at the behavioural outcomes of host-parasite relationships and the importance of studying them at multiple levels for understanding their origin and maintenance.

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Araújo, Adauto, e Luiz Fernando Ferreira. "Paleoparasitology and the antiquity of human host-parasite relationships". Memórias do Instituto Oswaldo Cruz 95, suppl 1 (2000): 89–93. http://dx.doi.org/10.1590/s0074-02762000000700016.

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CORALLINI, CARLA, e MARIA CLARA BICCHIERAI. "Trichoptera larvae and gregarines: Host-parasite relationships". Zoosymposia 10, n. 1 (9 agosto 2016): 148–64. http://dx.doi.org/10.11646/zoosymposia.10.1.12.

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The presence of eugregarines (Apicomplexa, Conoidasida, Eugregarinorida) in the larval midgut of several Trichoptera families found in Italy has been well established. Literature and our data indicate that gregarine infestation is influenced by the trichopteran diet and, except for a few cases, there is not a species-specific relationship. In this paper an updated list of Italian Trichoptera species hosting gregarines as well as data on the biology, morphology and ultrastructure of the corresponding parasites are presented. The host-parasite interaction was also investigated showing the involvement of the host diet in the onset of parasitosis and the influence of the host habitat on the degree of infestation.Gregarine infestation was massive in species inhabiting springs, particularly noticeable in close environments like troughs (“trocchi”) which are man-modified springs for drinking water for cattle. Larvae of Drusus improvisus found in the Tiber river springs were heavily infested and the parasite density at every season and the degree of infestation at each larval stage are reported.

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Garrido, C. T., A. L. Morassutti, J. R. S. Barradas e C. Graeff-Teixeira. "Evaluating host–parasite co-adaptation relationships involving Angiostrongylus costaricensis". Journal of Helminthology 93, n. 1 (19 dicembre 2017): 76–80. http://dx.doi.org/10.1017/s0022149x1700116x.

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AbstractAngiostrongylus costaricensis is a parasite that infects rodents, including the wild cotton rat Sigmodon hispidus and pygmy rice rats Oligoryzomys spp., among others. However, urban Rattus norvegicus and Mus musculus have not been identified as important hosts of A. costaricensis. In this study, Swiss mice (SW), Wistar R. norvegicus (RN), wild Oligoryzomys nigripes (ON) and a local strain of M. musculus (RGS) were experimentally infected with A. costaricensis. Survival, elimination of L1 (total sum per group, A0), and the number of adult worms recovered divided by the dose of each L3 inoculum (yield ratio, YR) were examined for each group after a 40-day post-infection period. The survival rates, A0 and YR values were: 27%, 207,589 and 0.42 for the SW group; 81%, 8691 and 0.01 for the RN group; and 63.6%, 26,560 and 0.16 for the RGS group, respectively, in each case. The survival rate for the ON group was 100% and the A0 value was 847,050. A YR was not calculated for the ON group since the ON group was maintained up to 565 days post-infection (pi) to examine long-term mortality. At 500 days pi (16 months), 50% of the ON group had died, while one animal (10%) survived 595 days pi (20 months). Taken together, these data indicate that A. costaricensis has undergone a greater degree of adaptation to the wild rodent, O. nigripes, than to R. norvegicus or a local M. musculus strain. In addition, titre curve (A0) modelling of adaptation status proved to be useful in evaluating A. costaricensis–rodent interactions.

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He, Yi-Xun, Buz Salafsky e Kalyanasundaram Ramaswamy. "Host–parasite relationships of Schistosoma japonicum in mammalian hosts". Trends in Parasitology 17, n. 7 (luglio 2001): 320–24. http://dx.doi.org/10.1016/s1471-4922(01)01904-3.

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Cornell, Stephen J., Yves Desdevises e Mark C. Rigby. "Evolutionary biology of host–parasite relationships: reality meets models". Trends in Ecology & Evolution 14, n. 11 (novembre 1999): 423–25. http://dx.doi.org/10.1016/s0169-5347(99)01727-9.

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39

Lammie, Patrick J. "T cell clones: Tools to investigate host-parasite relationships". Veterinary Parasitology 29, n. 2-3 (settembre 1988): 159–70. http://dx.doi.org/10.1016/0304-4017(88)90123-9.

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40

Zander, C. Dieter. "Ecology of Host Parasite Relationships in the Baltic Sea". Naturwissenschaften 85, n. 9 (1 settembre 1998): 426–36. http://dx.doi.org/10.1007/s001140050526.

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41

Zinner, Dietmar, Filipa M. D. Paciência e Christian Roos. "Host–Parasite Coevolution in Primates". Life 13, n. 3 (17 marzo 2023): 823. http://dx.doi.org/10.3390/life13030823.

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Abstract (sommario):

Organisms adapt to their environment through evolutionary processes. Environments consist of abiotic factors, but also of other organisms. In many cases, two or more species interact over generations and adapt in a reciprocal way to evolutionary changes in the respective other species. Such coevolutionary processes are found in mutualistic and antagonistic systems, such as predator–prey and host–parasite (including pathogens) relationships. Coevolution often results in an “arms race” between pathogens and hosts and can significantly affect the virulence of pathogens and thus the severity of infectious diseases, a process that we are currently witnessing with SARS-CoV-2. Furthermore, it can lead to co-speciation, resulting in congruent phylogenies of, e.g., the host and parasite. Monkeys and other primates are no exception. They are hosts to a large number of pathogens that have shaped not only the primate immune system but also various ecological and behavioral adaptions. These pathogens can cause severe diseases and most likely also infect multiple primate species, including humans. Here, we briefly review general aspects of the coevolutionary process in its strict sense and highlight the value of cophylogenetic analyses as an indicator for coevolution.

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KLIMOV, PAVEL B., LUIZ G. A. PEDROSO e QIXIN HE. "A probabilistic model predicting host specificity and host range expansion in mites parasitic on mammals". Zoosymposia 22 (30 novembre 2022): 48. http://dx.doi.org/10.11646/zoosymposia.22.1.18.

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The emergence of new mammalian diseases through the switching of parasitic organisms to novel hosts has significant wildlife, livestock, and human health impacts, however, new host switches are notoriously difficult to predict. The factors influencing the host switches are not fully understood because complete unbiased large-scale datasets of host-parasite relationships are lacking. Building a large-scale model to identify these factors and predict potential host switching (host range expansion) could hold substantial benefits from theoretical and applied perspectives (e.g., disease emergence prediction). Here we analyzed a large, curated database of host-parasite relationships of 1906 species of acariform mites forming permanent associations with 1235 species of mammals, including humans, and built a probabilistic predictive model of host-specificity for these mites. There was a total of 3,125 unique host-parasite records.

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43

Thompson, R. C. A., e A. J. Lymbery. "Genetic variability in parasites and host—parasite interactions". Parasitology 112, S1 (marzo 1996): S7—S22. http://dx.doi.org/10.1017/s0031182000076629.

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SUMMARYWe have examined genetic variability in parasites in the context of ecological interactions with the host. Recent research onEchinococcus, GiardiaandCryptosporidiumhas been used to illustrate: (i) the problems that parasite variability and species recognition pose for understanding the complex and often controversial relationship between parasite and host occurrence; (ii) the need for accurate parasite characterization and the application of appropriate molecular techniques to studies on parasite transmission if fundamental questions about zoonotic relationships and risk factors are to be answered; (iii) our lack of understanding about within-host interactions between genetically heterogeneous parasites at the inter-and intraspecific levels, and the significance of such interactions with respect to evolutionary considerations and the clinical outcome of parasite infections. If advances in molecular biology and mathematical ecology are to be realized, we need to give serious consideration to the development of appropriate species concepts and in vivo systems for testing the predictions and assumptions of theoretical models.

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44

CAMPIÃO, K. M., A. RIBAS e L. E. R. TAVARES. "Diversity and patterns of interaction of an anuran–parasite network in a neotropical wetland". Parasitology 142, n. 14 (7 ottobre 2015): 1751–57. http://dx.doi.org/10.1017/s0031182015001262.

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SUMMARYWe describe the diversity and structure of a host–parasite network of 11 anuran species and their helminth parasites in the Pantanal wetland, Brazil. Specifically, we investigate how the heterogeneous use of space by hosts changes parasite community diversity, and how the local pool of parasites exploits sympatric host species of different habits. We examined 229 anuran specimens, interacting with 32 helminth parasite taxa. Mixed effect models indicated the influence of anuran body size, but not habit, as a determinant of parasite species richness. Variation in parasite taxonomic diversity, however, was not significantly correlated with host size or habit. Parasite community composition was not correlated with host phylogeny, indicating no strong effect of the evolutionary relationships among anurans on the similarities in their parasite communities. Host–parasite network showed a nested and non-modular pattern of interaction, which is probably a result of the low host specificity observed for most helminths in this study. Overall, we found host body size was important in determining parasite community richness, whereas low parasite specificity was important to network structure.

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Tennakoon, Kushan U., Wang H. Chak e Jay F. Bolin. "Nutritional and isotopic relationships of selected Bornean tropical mistletoe–host associations in Brunei Darussalam". Functional Plant Biology 38, n. 6 (2011): 505. http://dx.doi.org/10.1071/fp10211.

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Our understanding of mineral nutrition and carbon heterotrophy in mistletoes is derived largely from arid and temperate plant communities. Sharp differences between the tropical, temperate and arid communities, such as seasonality, water availability and mean temperature may influence basic assumptions regarding mistletoe physiology. Thus, we present mineral nutrition profiles and natural abundance carbon and nitrogen stable isotope data for tropical mistletoes and their hosts. Parasite–host mineral nutrition profiles were estimated for three Loranthaceous mistletoes: Scurrula ferruginea Danser, Macrosolen cochinchinensis Blume, and Dendrophthoe curvata Blume and 12 unique mistletoe–host associations. δ13C and δ15N values were estimated for 12 parasite–host associations. Differences between host and parasite δ13C values were small but showed significant depletion in mistletoe leaves compared with the distal branch and proximal branch host leaves. Host and mistletoe δ13C values were uncorrelated whereas δ15N values were significantly correlated, demonstrating mistletoe N dependence. Concentrations of K were higher in mistletoes relative to hosts and significantly higher for Dendrophthoe host associations. For Scurrula and Macrosolen, mean mistletoe–host concentrations of major and minor elements did not differ significantly.

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MARQUES, J. F., M. J. SANTOS, C. M. TEIXEIRA, M. I. BATISTA e H. N. CABRAL. "Host-parasite relationships in flatfish (Pleuronectiformes) – the relative importance of host biology, ecology and phylogeny". Parasitology 138, n. 1 (7 settembre 2010): 107–21. http://dx.doi.org/10.1017/s0031182010001009.

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SUMMARYThe extent to which host biology, ecology and phylogeny determine the diversity of macroparasite assemblages has been investigated in recent years in several taxa, including fish. However, consensus has not been reached probably as a result of data being collected from different sources, different temporal scales or host and parasite biogeography and phylogeny having greater influence than expected. The present study evaluates the relative importance of 27 biological, ecological and phylogenetic characteristics of 14 flatfish species on the diversity of their ecto- and endoparasite assemblages, comprising a total of 53 taxa. Redundancy analyses were applied to the mean abundance of each parasite taxa infecting each host and to the richness, taxonomic distinctness and variance in taxonomic distinctness calculated for each assemblage within each host. Only a few host characteristics contributed significantly to the observed patterns: host distribution was more important in determining the type and mean abundance of ectoparasites present in an assemblage, whereas diversity of these assemblages were mainly related to the host's maximum size. Endoparasite mean abundance and diversity were mostly influenced by the number of food items ingested and by the presence of Crustacea and Polychaeta in the diet. However, the sympatric occurrence of related hosts also played an important role in the diversity values found in macroparasite assemblages. Results showed that a host characteristic has different importance according to the host-parasite relationship being examined, suggesting an important role for host-parasite co-evolution on the diversity of extant macroparasite assemblages.

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Romero-Rodríguez, J., e R. Román-Contreras. "Relationships of the branchial parasite Bopyrinella thorii (Isopoda, Bopyridae) and its host Thor floridanus (Decapoda, Hippolytidae)". Crustaceana 87, n. 4 (2014): 463–75. http://dx.doi.org/10.1163/15685403-00003298.

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Morphometric data are presented for developmental stages ofBopyrinellathorii(Richardson, 1904), obtained from 380 individuals ofThorfloridanusKingsley, 1878 infested by this parasite and collected by trawl net in Bahía de la Ascensión, Quintana Roo, Mexico. The close relationships between the sizes of host and parasite () and between sizes of the two sexes of the parasite () suggest the simultaneous growth of host and parasite and the permanence of the pairing of a male and female parasite throughout their lives. Cryptoniscus larvae ofB. thoriiwere sometimes attached intramuscularly to other body parts than the host’s gill chambers. Mature females unpaired with a male had ovarian activity visible through their exoskeleton, which reveals thatB. thoriicould produce oocytes even in the absence of a male. Bilateral double infestation, present in 4.2% of theT. floridanusspecimens analysed, was more frequent in smaller size classes of the host.

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SHEATH, DANNY J., DEMETRA ANDREOU e J. ROBERT BRITTON. "Interactions of warming and exposure affect susceptibility to parasite infection in a temperate fish species". Parasitology 143, n. 10 (26 maggio 2016): 1340–46. http://dx.doi.org/10.1017/s0031182016000846.

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SUMMARYPredicting how elevated temperatures from climate change alter host–parasite interactions requires understandings of how warming affects host susceptibility and parasite virulence. Here, the effect of elevated water temperature and parasite exposure level was tested on parasite prevalence, abundance and burden, and on fish growth, using Pomphorhynchus laevis and its fish host Squalius cephalus. At 60 days post-exposure, prevalence was higher at the elevated temperature (22 °C) than ambient temperature (18 °C), with infections achieved at considerably lower levels of exposure. Whilst parasite number was significantly higher in infected fish at 22 °C, both mean parasite weight and parasite burden was significantly higher at 18 °C. There were, however, no significant relationships between fish growth rate and temperature, parasite exposure, and the infection parameters. Thus, whilst elevated temperature significantly influenced parasite infection rates, it also impacted parasite development rates, suggesting warming could have complex implications for parasite dynamics and host resistance.

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Dereure, Jacques, Sayda Hassan El-Safi, Bruno Bucheton, Mickaël Boni, Musa Mohamed Kheir, Bernard Davoust, Francine Pratlong et al. "Visceral leishmaniasis in eastern Sudan: parasite identification in humans and dogs; host-parasite relationships". Microbes and Infection 5, n. 12 (ottobre 2003): 1103–8. http://dx.doi.org/10.1016/j.micinf.2003.07.003.

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Marciniak-Musial, Natalia, Maciej Skoracki, Jakub Z. Kosicki, Markus Unsöld e Bozena Sikora. "Host-Parasite Relationships of Quill Mites (Syringophilidae) and Parrots (Psittaciformes)". Diversity 15, n. 1 (20 dicembre 2022): 1. http://dx.doi.org/10.3390/d15010001.

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The family Syringophilidae (Acari: Prostigmata) includes obligatory ectoparasites, which occupy feather quills from various parts of avian plumage, where they feed and reproduce. Our study was concerned with the global fauna of syringophilid mites associated with Psittaciformes, as well as host-parasite specificity and evolution. We assumed that the system composed of quill mites and parrots represents a model group that can be used in a broader study of the relationships between parasites and hosts. In total, we examined 1524 host individuals of parrots belonging to 195 species, 73 genera, and 4 families (which constitute ca. 50% of global parrot fauna) from all zoogeographical regions where Psittaciformes occur. Among them, 89 individuals representing 81 species have been infested by quill mites belonging to 45 species and 8 genera. The prevalence of host infestations by syringophilid mites varied from 2.8% to 100% (95% confidence interval (CI Sterne method) = 0.1–100). We applied a bipartite analysis to determine the parasite-host interaction, network indices, and host specificity at the species and whole network levels. The Syringophilidae-Psittaciformes network was composed of 24 mite species and 47 host species. The bipartite network was characterized by a high network level specialization H2′ = 0.98, connectance C = 0.89, and high modularity Q = 0.90, with 23 modules, but low nestedness N = 0.0333. Moreover, we reconstructed the phylogeny of the quill mites on the generic level, and this analysis shows two distinct clades: Psittaciphilus (Peristerophila + Terratosyringophilus) (among Syringophilinae subfamily) and Lawrencipicobia (Pipicobia + Rafapicobia) (among Picobiinae). Finally, the distributions and host-parasite relationships in the system composed of syringophilid mites and parrots are discussed.

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