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Recombinant DNA Technology and Gene Therapy Using Viruses
Published in Patricia G. Melloy, Viruses and Society, 2023
In this textbook, we have mainly talked about viruses as agents of disease. However, viruses are a part of our world, and they have other roles to play on the planet. For example, we know that viruses can form in a “symbiotic relationship” with their organismal host, which can result in mutualism where both the virus and host gain some benefit (Mietzsch and Agbandje-McKenna 2017; Roossinck 2011). In addition, scientists have harnessed the power of viruses to use them to treat disease, including using viruses to fight cancer, as was mentioned in Chapter 1 (Mietzsch and Agbandje-McKenna 2017; Brown 2020). Scientists also can use modified viruses for gene therapy and vaccines. Any time a virus is used to treat a disease, it is known as virotherapy (Mietzsch and Agbandje-McKenna 2017).
An Introduction to Parasitism
Published in Eric S. Loker, Bruce V. Hofkin, Parasitology, 2023
Eric S. Loker, Bruce V. Hofkin
Whereas parasitism benefits one partner at the expense of another, mutualism benefits both interacting partners, so at first blush, the two categories of symbiotic associations seem quite distinct. Before we delve into the properties of parasites in later chapters, it is important to gain a better appreciation for some of the nuances of mutualism and see how it interfaces with parasitism. As noted by Herre et al. (1999), “mutualisms are ubiquitous, often ecologically dominant, and profoundly influential at all levels of biological organization.” Just as with parasitism, our appreciation for the complexities of mutualism has been enhanced by the application of modern visualization and molecular techniques (Figure 1.15).
Interactions between Oral Bacteria and Antibacterial Polymer-Based Restorative Materials
Published in Mary Anne S. Melo, Designing Bioactive Polymeric Materials for Restorative Dentistry, 2020
Fernando L. Esteban Florez, Sharukh S. Khajotia
The final stage in the development of biofilms is typically associated with the release of cells from the biofilm community into the environment. Such an essential stage in the lifecycle of biofilms (1) accounts for the increased biological heterogeneity observed in the oral cavity, (2) is known to contribute to the survival of bacteria actively, and ultimately, (3) leads to the transmission of bacterial-originated oral diseases.[80] As for the example of the phases previously described, bacterial detachment is typically regulated by many complex mechanisms involving numerous environmental signals, transduction pathways, and effectors.[81] Passive mechanisms may include quorum-sensing, matrix-degrading enzymes (dpsB, hyaluronidase), and external agents, such as fluid shear forces, abrasion by the collision of solid particulates, predator grazing, and human intervention.[82–84] Active mechanisms, on the other hand, are controlled by the bacteria and include the excretion of inter-species antimicrobial compounds, competition, mutualism, and parasitism.
Modeling spatial interaction networks of the gut microbiota
Published in Gut Microbes, 2022
Xiaocang Cao, Ang Dong, Guangbo Kang, Xiaoli Wang, Liyun Duan, Huixing Hou, Tianming Zhao, Shuang Wu, Xinjuan Liu, He Huang, Rongling Wu
Third, the networks reconstructed by qdODE can omnidirectionally capture ecological interactions that occur among microbes. It can cover all possible types of microbial interactions, including mutualism (two microbes promote each other by producing factors that are beneficial for both interacting parties), antagonism (two microbes inhibit each other), commensalism (one microbe promotes its partner whereas the latter does not affect the former), amensalism (one microbe inhibits the other and the other is neutral), and parasitism (one microbe inhibits the other but the latter promotes the former). The opposite to parasitism is altruism (one microbe promotes the other but the latter inhibits the former).25,49,52 A microbe may actively manipulate other microbes (by promoting or inhibiting the latter) and, meanwhile, it may be passively manipulated by other microbes. In an idopNetwork, one can identify the numbers of such active links and passive links for each microbe. If a microbe has more active links than passive links, it is regarded as a leader microbe. If a microbe’s active links are more than the average of all microbes (i.e., connectivity), then this microbe is a mighty hub or keystone microbe that is believed to play a pivotal role in maintaining microbial communities. If a microbe has less links, including active and passive, than the average, it is a solitary microbe. The ecological interpretation of these strategies will stimulate researchers to explore the mass, energetic, or signal basis of microbial interactions.53
Diversity of site-specific microbes of occlusal and proximal lesions in severe- early childhood caries (S-ECC)
Published in Journal of Oral Microbiology, 2022
Kausar Sadia Fakhruddin, Lakshman Perera Samaranayake, Rifat Akram Hamoudi, Hien Chi Ngo, Hiroshi Egusa
We noted that S. mutans and V. alcalescens were the most prevalent species amongst all evaluated caries sites. There is an ample narrative on the link between S. mutans and dental caries due to its superior acidogenic and aciduric potential [13,42,43]. Our data confirms a report by Aas et al. (2008), who also noted that the most prevalent species in either the occlusal or proximal caries of children with S-ECC is S. mutans [13]. Another observation that substantiates the work of the latter group [13] is the profusion of V. alcalescens, which we noted in both the occlusal and proximal deep-dentine locales (p ≥ 0.05). Classically, Veillonella spp. and S. mutans are known to be co-located and intimately associated with the caries process. The former is thought to nutritionally metabolize the carboxylic acids produced by streptococci, and thereby suppress the cariogenicity of the mutans-group of streptococci [44]. On the contrary, others have noted that V. alcalescens and S. mutans in tandem produce more acids than each of the species separately [45]. Veillonella species also easily coaggregate with various oral microbes, including Streptococcus spp [46]. thus suggesting a high degree of synergism and mutualism between them [45,47], as was noted here.
Novel avenues for identification of new antifungal drugs and current challenges
Published in Expert Opinion on Drug Discovery, 2022
Fungi are simple eukaryotic organisms that are able to colonize various environments around the planet. It is estimated that there are approx. 2 million different species. They are ubiquitous in nature and are vital for the recycling of nutrients contained in organic matter (most species of fungi are saprophytes). They coexist with other organisms on the basis of mutualism, commensalism, and, unfortunately, parasitism [1,2]. Higher fungi have been used by people in the kitchen, brewing, viticulture, and folk medicine for thousands of years. Microscopic as well as higher fungi are used in biotechnology for the production or biotransformation of various substances and, in recent years, also popular for the green synthesis of nanoparticles. Biologically active secondary metabolites of higher fungi and microscopic fungi have become the inspiration for the design of drug structures [3–5].