Publications by authors named "J P Scharsack"

Evidence that the innate immune system can respond with forms of memory upon reinfection has been accumulating over the past few years. These phenomena of "immune priming" in invertebrates, and "trained immunity" in vertebrates, are contrary to previous belief that immune memory and specificity are restricted to the adaptive immune system. However, while trained immunity is usually a response with rather low specificity, immune priming has shown highly specific responses in certain species.

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Environmental factors can cause cancer in both wild animals and humans. In ecological settings, genetic variation and natural selection can sometimes produce resilience to the negative impacts of environmental change. An increase in oncogenic substances in natural habitats has therefore, unintentionally, created opportunities for using polluted habitats to study cancer defence mechanisms.

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Many species in aquatic environments face increased exposure to oncogenic pollution due to anthropogenic environmental change which can lead to higher cancer prevalence. The mechanistic relationship connecting environmental pollution and cancer is multi-factorial and poorly understood, and the specific mechanisms are so far still uncharacterized. One potential mediator between pollutant exposure and cancer is oxidative damage to DNA.

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Stable isotope analysis of individual compounds is emerging as a powerful tool to study nutrient origin and conversion in host-parasite systems. We measured the carbon isotope composition of amino acids and glucose in the cestode Schistocephalus solidus and in liver and muscle tissues of its second intermediate host, the three-spined stickleback (Gasterosteus aculeatus), over the course of 90 days in a controlled infection experiment. Similar linear regressions of δC values over time and low trophic fractionation of essential amino acids indicate that the parasite assimilates nutrients from sources closely connected to the liver metabolism of its host.

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Temperature is an important environmental modulator of teleost immune activity. Susceptibility of teleosts to temperature variation depends on the species-specific adaptive temperature range, and the activity of the teleost immune system is generally temperature-dependent. Similar to many physiological and metabolic traits of ectotherms, temperature modulates the activity of immune traits.

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