Frequency-dependent transmission is an important feature of diseases that are sexually transmitted or transmitted by a vector that actively searches for hosts. Here I describe the evolution of virulence in pathogens that have frequency-dependent transmission. I consider two components of virulence--an increase in host mortality due to infection, as is classically described, and a decrease in host fecundity due to infection, because frequency dependence is common among diseases that fully or partially sterilize their hosts. Theoretical predictions pertaining to host-pathogen numerical dynamics can be quite different between pathogens with frequency-dependent transmission and those with density-dependent transmission. In contrast, this study suggests that the principles governing the evolution of virulence that have been established in the context of density-dependent pathogens may also apply (qualitatively) to frequency-dependent pathogens. I examine the evolutionary trajectories of the mortality and sterility components of virulence as well as the role of spatial population structure in the evolution of the sterility component of virulence.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.jtbi.2004.09.005 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Muscarinic Modulation of Network Excitability and Short-Term Dynamics in the Dorsal and Ventral Hippocampus.
MicroPubl Biol
December 2024
Laboratory of Physiology, Department of Medicine, University of Patras, Pátrai, West Greece, Greece.
Cholinergic transmission fundamentally modulates information processing in the brain via muscarinic receptors. Using electrophysiological recordings of population spikes from the CA1 region, we found that the muscarinic receptor agonist carbachol (CCh, 1 μM) enhances the basal excitation level in the dorsal but not ventral hippocampus. Using a frequency stimulation protocol, we found that CCh transforms depression of neuronal output into facilitation (at 3-30 Hz) in the ventral hippocampus while only lessening depression in the dorsal hippocampus, suggesting that muscarinic transmission boosts basal neuronal activation in the dorsal hippocampus and strongly facilitates the output of the ventral hippocampus in a frequency-dependent manner.
View Article and Find Full Text PDFAmorphous Carbon Monolayer: A van der Waals Interface for High-Performance Metal Oxide Semiconductor Devices.
ACS Nano
December 2024
Department of Materials Science and Engineering, Hanbat National University, Daejeon 34158, Republic of Korea.
Ultrasmall-scale semiconductor devices (≤5 nm) are advancing technologies, such as artificial intelligence and the Internet of Things. However, the further scaling of these devices poses critical challenges, such as interface properties and oxide quality, particularly at the high-/semiconductor interface in metal-oxide-semiconductor (MOS) devices. Existing interlayer (IL) methods, typically exceeding 1 nm thickness, are unsuitable for ultrasmall-scale devices.
View Article and Find Full Text PDFAnalyzing Spinal Cord Stimulation With Different Electrode Configurations: A Numerical Study.
Int J Numer Method Biomed Eng
January 2025
Department of Biomedical Engineering, Inonu University, Malatya, Türkiye.
Spinal cord stimulation (SCS) represents a therapeutic approach for chronic pain management in patients refractory to conventional treatments. By implanting electrodes in the epidural space, SCS aims to mitigate pain transmission to the brain through electrical stimulation, often resulting in sensory perceptions such as paresthesia. This study investigates the influence of electrode configurations on electrical parameters, including current density and electric potential, within the spinal cord environment.
View Article and Find Full Text PDFMetapopulation heterogeneities in host mobility, productivity, and immunocompetency always increase virulence and infectiousness.
Proc Natl Acad Sci U S A
December 2024
Complexity Science and Evolution Unit, Okinawa Institute of Science and Technology Graduate University (OIST), Tancha, Onna, Kunigami, Okinawa 904-0495, Japan.
The epidemiology and evolution of diseases unfold in populations that are rarely homogeneous. Instead, hosts infected by pathogens often form metapopulations, in which local populations connected by the movement of hosts experience different demographic and epidemiological conditions. Here, we develop a general theory of the evolution of pathogens in heterogeneous metapopulations.
View Article and Find Full Text PDFDistinct release properties of glutamate/GABA co-transmission serve as a frequency-dependent filtering of supramammillary inputs.
Elife
December 2024
Graduate School of Brain Science, Doshisha University, Kyoto, Japan.
Glutamate and GABA co-transmitting neurons exist in several brain regions; however, the mechanism by which these two neurotransmitters are co-released from the same synaptic terminals remains unclear. Here, we show that the supramammillary nucleus (SuM) to dentate granule cell synapses, which co-release glutamate and GABA, exhibit differences between glutamate and GABA release properties in paired-pulse ratio, Ca-sensitivity, presynaptic receptor modulation, and Ca channel-vesicle coupling configuration. Moreover, uniquantal synaptic responses show independent glutamatergic and GABAergic responses.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!