One of the challenges in epidemiology is to account for the complex morphological structure of hosts such as plant roots, crop fields, farms, cells, animal habitats and social networks, when the transmission of infection occurs between contiguous hosts. Morphological complexity brings an inherent heterogeneity in populations and affects the dynamics of pathogen spread in such systems. We have analysed the influence of realistically complex host morphology on the threshold for invasion and epidemic outbreak in an SIR (susceptible-infected-recovered) epidemiological model. We show that disorder expressed in the host morphology and anisotropy reduces the probability of epidemic outbreak and thus makes the system more resistant to epidemic outbreaks. We obtain general analytical estimates for minimally safe bounds for an invasion threshold and then illustrate their validity by considering an example of host data for branching hosts (salamander retinal ganglion cells). Several spatial arrangements of hosts with different degrees of heterogeneity have been considered in order to separately analyse the role of shape complexity and anisotropy in the host population. The estimates for invasion threshold are linked to morphological characteristics of the hosts that can be used for determining the threshold for invasion in practical applications.
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http://dx.doi.org/10.1098/rsif.2009.0475 | DOI Listing |
Inflamm Res
January 2025
Department of Anesthesiology, Critical Care, and Surgery, Duke University School of Medicine, Durham, NC, USA.
Background: Mitochondria generate the adenosine triphosphate (ATP) necessary for eukaryotic cells, serving as their primary energy suppliers, and contribute to host defense by producing reactive oxygen species. In many critical illnesses, including sepsis, major trauma, and heatstroke, the vicious cycle between activated coagulation and inflammation results in tissue hypoxia-induced mitochondrial dysfunction, and impaired mitochondrial function contributes to thromboinflammation and cell death.
Methods: A computer-based online search was performed using the PubMed and Web of Science databases for published articles concerning sepsis, trauma, critical illnesses, cell death, mitochondria, inflammation, coagulopathy, and organ dysfunction.
Nat Commun
January 2025
Division of Virology, Institute of Medical Science, University of Tokyo, Tokyo, Japan.
Microthrombus formation is associated with COVID-19 severity; however, the detailed mechanism remains unclear. In this study, we investigated mouse models with severe pneumonia caused by SARS-CoV-2 infection by using our in vivo two-photon imaging system. In the lungs of SARS-CoV-2-infected mice, increased expression of adhesion molecules in intravascular neutrophils prolonged adhesion time to the vessel wall, resulting in platelet aggregation and impaired lung perfusion.
View Article and Find Full Text PDFJ Helminthol
January 2025
Center of Parasitology of A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences, Leninskii Prospect 33, 117071, Moscow, Russia.
Studying complexes of cryptic or pseudocryptic species opens new horizons for the understanding of speciation processes, an important yet vague issue for the digeneans. We investigated a hemiuroidean trematode across a wide geographic range including the northern European seas (White, Barents, and Pechora), East Siberian Sea, and the Pacific Northwest (Sea of Okhotsk and Sea of Japan). The goals were to explore the genetic diversity within through mitochondrial ( and genes) and ribosomal (ITS1, ITS2, 28S rDNA) marker sequences, to study morphometry of maritae, and to revise the life cycle data.
View Article and Find Full Text PDFMicrobial pathogens generate extracellular vesicles (EVs) for intercellular communication and quorum sensing. Microbial EVs also induce inflammatory pathways within host innate immune cells. We previously demonstrated that EVs secreted by trigger type I interferon signaling in host cells specifically via the cGAS-STING innate immune signaling pathway.
View Article and Find Full Text PDFInt J Parasitol Parasites Wildl
April 2025
Guangxi Key Laboratory of Diabetic Systems Medicine, Guilin Medical University, Guilin, 541199, PR China.
To investigate the infection of fish of the genus by (Monogenea) parasites in the karst region of Yunnan (Southwest China), individuals were obtained from the rare and vulnerable host black loach . Based on morphology and partial internal transcribed spacer (ITS) sequence data, we identified and described a new species n. sp.
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