Download or read book Amoebae as Host Models to Study the Interaction with Pathogens written by Sascha Thewes and published by Frontiers Media SA. This book was released on 2019-08-27 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt: The human body is constantly faced with microorganisms. Most of these bacteria, fungi, and viruses are harmless, many of them are beneficial, and a small fraction is pathogenic. For humans, infection with pathogenic microorganisms can be very serious or even fatal, ranging from mild transient or chronic infections to death. The first line of defence against pathogens is our innate immune system. Beside chemical and physical defence mechanisms of the innate immune system, phagocytic cells such as macrophages play a crucial role in the fight against pathogenic microorganisms. However, phagocytic cells and pathogens are in a constant evolutionary arms race, inventing new strategies to successfully kill pathogens and learning how to resist phagocytosis and intracellular killing, respectively. If pathogens are not obligatory adapted to the human body or other animals, they also have to face environmental phagocytes in the form of amoebae. Many aspects of phagocytosis and intracellular killing are surprisingly well conserved between amoebae and macrophages. Therefore, pathogens that have evolved with environmental amoebae as their “training grounds” can also be successful during infection of macrophages and other animal phagocytic cells. In this Research Topic, we provide the latest knowledge about the potential of using amoebae as host models to study the interaction with pathogens. The Research Topic covers the interaction of amoebae with bacteria, fungi, and viruses and also illustrates the similarities and differences between amoebae and macrophages. Investigation of evolutionary conserved pathways of amoebae and macrophages furthers our understanding of the biology of host-pathogen interactions and helps to develop new anti-infection therapies.
Download or read book Molecular Biology of the Cell written by and published by . This book was released on 2002 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Acanthamoeba written by Naveed Ahmed Khan and published by Caister Academic Press Limited. This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This fully up-to-date book covers all aspects of Acanthamoeba biology. Following the success of the first edition, the author has extensively revised and expanded the text to produce a new volume that includes all the latest research and information on every aspect of this organism. There is a particular emphasis on the Acanthamoeba genome sequence and the novel insights gained from the application of molecular methods to Acanthamoeba developmental/cellular biology, in terms of metabolism and morphogenesis, classification, ecology and role in the ecosystem, host-pathogen interactions, virulence factors and immunological basis of pathogenesis, clinical manifestation, diagnosis, treatment, new target development, and drug resistance and its interactions with other microbes in the environment. The book will be an essential reference text for parasitologists, microbiologists, immunologists, and physicians in the field of basic and medical microbiology, as well as an invaluable reference for new and experienced researchers who wish to better understand this organism.
Download or read book The Social Biology of Microbial Communities written by Institute of Medicine and published by National Academies Press. This book was released on 2013-01-10 with total page 633 pages. Available in PDF, EPUB and Kindle. Book excerpt: Beginning with the germ theory of disease in the 19th century and extending through most of the 20th century, microbes were believed to live their lives as solitary, unicellular, disease-causing organisms . This perception stemmed from the focus of most investigators on organisms that could be grown in the laboratory as cellular monocultures, often dispersed in liquid, and under ambient conditions of temperature, lighting, and humidity. Most such inquiries were designed to identify microbial pathogens by satisfying Koch's postulates.3 This pathogen-centric approach to the study of microorganisms produced a metaphorical "war" against these microbial invaders waged with antibiotic therapies, while simultaneously obscuring the dynamic relationships that exist among and between host organisms and their associated microorganisms-only a tiny fraction of which act as pathogens. Despite their obvious importance, very little is actually known about the processes and factors that influence the assembly, function, and stability of microbial communities. Gaining this knowledge will require a seismic shift away from the study of individual microbes in isolation to inquiries into the nature of diverse and often complex microbial communities, the forces that shape them, and their relationships with other communities and organisms, including their multicellular hosts. On March 6 and 7, 2012, the Institute of Medicine's (IOM's) Forum on Microbial Threats hosted a public workshop to explore the emerging science of the "social biology" of microbial communities. Workshop presentations and discussions embraced a wide spectrum of topics, experimental systems, and theoretical perspectives representative of the current, multifaceted exploration of the microbial frontier. Participants discussed ecological, evolutionary, and genetic factors contributing to the assembly, function, and stability of microbial communities; how microbial communities adapt and respond to environmental stimuli; theoretical and experimental approaches to advance this nascent field; and potential applications of knowledge gained from the study of microbial communities for the improvement of human, animal, plant, and ecosystem health and toward a deeper understanding of microbial diversity and evolution. The Social Biology of Microbial Communities: Workshop Summary further explains the happenings of the workshop.
Download or read book Management of Legionella in Water Systems written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2020-02-20 with total page 291 pages. Available in PDF, EPUB and Kindle. Book excerpt: Legionnaires' disease, a pneumonia caused by the Legionella bacterium, is the leading cause of reported waterborne disease outbreaks in the United States. Legionella occur naturally in water from many different environmental sources, but grow rapidly in the warm, stagnant conditions that can be found in engineered water systems such as cooling towers, building plumbing, and hot tubs. Humans are primarily exposed to Legionella through inhalation of contaminated aerosols into the respiratory system. Legionnaires' disease can be fatal, with between 3 and 33 percent of Legionella infections leading to death, and studies show the incidence of Legionnaires' disease in the United States increased five-fold from 2000 to 2017. Management of Legionella in Water Systems reviews the state of science on Legionella contamination of water systems, specifically the ecology and diagnosis. This report explores the process of transmission via water systems, quantification, prevention and control, and policy and training issues that affect the incidence of Legionnaires' disease. It also analyzes existing knowledge gaps and recommends research priorities moving forward.
Download or read book Indicators for Waterborne Pathogens written by National Research Council and published by National Academies Press. This book was released on 2004-06-19 with total page 329 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent and forecasted advances in microbiology, molecular biology, and analytical chemistry have made it timely to reassess the current paradigm of relying predominantly or exclusively on traditional bacterial indicators for all types of waterborne pathogens. Nonetheless, indicator approaches will still be required for the foreseeable future because it is not practical or feasible to monitor for the complete spectrum of microorganisms that may occur in water, and many known pathogens are difficult to detect directly and reliably in water samples. This comprehensive report recommends the development and use of a "tool box" approach by the U.S Environmental Protection Agency and others for assessing microbial water quality in which available indicator organisms (and/or pathogens in some cases) and detection method(s) are matched to the requirements of a particular application. The report further recommends the use of a phased, three-level monitoring framework to support the selection of indicators and indicator approaches.Â
Download or read book Dictyostelium written by Richard H. Kessin and published by Cambridge University Press. This book was released on 2001-01-11 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dictyostelia are soil amoebae capable of extraordinary feats of survival, motility, chemotaxis, and development. Characterised by their ability to transform from a single-celled organism into an elaborate assemblage of thousands of synchronously-moving cells, Dictyostelids are often referred to as 'social amoebae', and have been the subjects of serious study since the 1930s. Research in this area has been instrumental in understanding many problems in cellular biology. Beginning with the history of Dictyostelids and discussing each stage of their development, this book considers the evolution of this unique organism, analyses the special properties of the Dictyostelid genome, and presents in detail the methods available, at the time of the book's original publication in 2001, to manipulate their genes. Representing the synthesis of such material and with an emphasis on combining classical experiments with modern molecular findings, this book will be essential for researchers and graduates in developmental and cellular biology.
Download or read book Model Organisms for Microbial Pathogenesis Biofilm Formation and Antimicrobial Drug Discovery written by Busi Siddhardha and published by Springer Nature. This book was released on 2020-03-28 with total page 685 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides essential insights into microbial pathogenesis, host-pathogen interactions, and the anti-microbial drug resistance of various human pathogens on the basis of various model organisms. The initial sections of the book introduce readers to the mechanisms of microbial pathogenesis, host-pathogen interactions, anti-microbial drug resistance, and the dynamics of biofilm formation. Due to the emergence of various microbial resistant strains, it is especially important to understand the prognosis for microbial infections, disease progression profiles, and mechanisms of resistance to antibiotic therapy in order to develop novel therapeutic strategies. In turn, the second part of the book presents a comparative analysis of various animal models to help readers understand microbial pathogenesis, host-pathogen interactions, anti-microbial drug discovery, anti-biofilm therapeutics, and treatment regimes. Given its scope, the book represents a valuable asset for microbiologists, biotechnologists, medical professionals, drug development researchers, and pharmacologists alike.
Download or read book Soil Protists written by Stefan Geisen and published by Sudwestdeutscher Verlag Fur Hochschulschriften AG. This book was released on 2015-10-13 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: Protists are by far the most diverse and abundant eukaryotes in soils. Nevertheless, very little is known about individual representatives, the diversity and community composition and ecological functioning of these important organisms. For instance, soil protists are commonly lumped into a single functional unit, i.e. bacterivores. This work tackles missing knowledge gaps on soil protists and common misconceptions using multi-methodological approaches including cultivation, microcosm experiments and environmental sequencing. In a first part, several new species and genera of amoeboid protists are described showing their immense unknown diversity. In the second part, the enormous complexity of soil protists communities is highlighted using cultivation- and sequence-based approaches. In the third part, the present of diverse mycophagous and nematophagous protists are shown in functional studies on cultivated taxa and their environmental importance supported by sequence-based approaches. This work is just a start for a promising future of soil Protistology that is likely to find other important roles of these diverse organisms.
Download or read book The Mononuclear Phagocyte System in Infectious Disease written by Geanncarlo Lugo-Villarino and published by Frontiers Media SA. This book was released on 2019-10-04 with total page 790 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Mononuclear Phagocyte System (MPS) of vertebrates is composed of monocytes, macrophages and dendritic cells. Together, they form part of the first line of immune defense against a variety of pathogens (bacteria, fungi, parasites and viruses), and thus play an important role in maintaining organism homeostasis. The mode of transmission, type of replication and mechanism of disease-causing differ significantly for each pathogen, eliciting a unique immune response in the host. Within this context, the MPS acts as both the sentinel and tailor of the immune system. As sentinels, MPS cells are found in blood and within tissues throughout the body to patrol against pathogenic insult. The strategy to detect 'microbial non-self' relies on MPS to recognize conserved microbial products known as 'pathogen-associated molecular pattern' (PAMPs). PAMPs recognition represents a checkpoint in the response to pathogens and relies on conserved 'pattern recognition receptors' (PRRs). Upon PRR engagement, MPS mount a cell-autonomous attack that includes the internalization and compartmentalization of intracellular pathogens into toxic compartments that promote destruction. In parallel, MPS cells launch an inflammatory response composed of a cellular arm and soluble factors to control extracellular pathogens. In cases when innate immunity fails to eliminate the invading microbe, MPS serves as a tailor to generate adaptive immunity for pathogen eradication and generation of "memory" cells, thus ensuring enhanced protection against re-infection. Indeed, MPS cell functions comprise the capture, process, migration and delivery of antigenic information to lymphoid organs, where type-1 immunity is tailored against intracellular microbes and type-2 immunity against extracellular pathogens. However, this potent adaptive immunity is also a double-edge sword that can cause aberrant inflammatory disorders, like autoimmunity or chronic inflammation. For this reason, MPS also tailors tolerance immunity against unwanted inflammation. Successful clearance of the microbe results in its destruction and proper collection of debris, resolution of inflammation and tissue healing for which MPS is essential. Reciprocally, as part of the evolutionary process taking place in all organisms, microbes evolved strategies to circumvent the actions bestowed by MPS cells. Multiple pathogens modulate the differentiation, maturation and activation programs of the MPS, as an efficient strategy to avoid a dedicated immune response. Among the most common evasion strategies are the subversion of phagocytosis, inhibition of PRR-mediated immunity, resistance to intracellular killing by reactive oxygen and nitrogen species, restriction of phagosome maturation, modulation of cellular metabolism and nutrient acquisition, regulation of cell death and autophagy, and modulation of pro-inflammatory responses and hijacking of tolerance mechanisms, among others. The tenet of this eBook is that a better understanding of MPS in infection will yield insights for development of therapeutics to enhance antimicrobial processes or dampen detrimental inflammation for the host's benefit. We believe that contributions to this topic will serve as a platform for discussion and debate about relevant issues and themes in this field. Our aim is to bring expert junior and senior scientists to address recent progress, highlight critical knowledge gaps, foment scientific exchange, and establish conceptual frameworks for future MPS investigation in the context of infectious disease.
Download or read book Dictyostelium A Tractable Cell and Developmental Model in Biomedical Research written by Robert J. Huber and published by Frontiers Media SA. This book was released on 2022-08-16 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ending the War Metaphor written by Institute of Medicine and published by National Academies Press. This book was released on 2006-06-09 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: Infectious diseases have existed longer than us, as long as us, or are relatively newer than us. It may be the case that a disease has existed for many, many years but has only recently begun affecting humans. At the turn of the century the number of deaths caused by infections in the United States had been falling steadily but since the '80s has seen an increase. In the past 30 years alone 37 new pathogens have been identified as human disease threats and 12% of known human pathogens have been classified as either emerging or remerging. Whatever the story, there is currently a "war" on infectious diseases. This war is simply the systematic search for the microbial "cause" of each disease, followed by the development of antimicrobial therapies. The "war" on infectious diseases, however, must be revisited in order to develop a more realistic and detailed picture of the dynamic interactions among and between host organisms and their diverse populations of microbes. Only a fraction of these microbes are pathogens. Thus, in order to explore the crafting of a new metaphor for host-microbe relationships, and to consider how such a new perspective might inform and prioritize biomedical research, the Forum on Microbial Threats of the Institute of Medicine (IOM) convened the workshop, Ending the War Metaphor: The Changing Agenda for Unraveling the Host-Microbe Relationship on March 16-17, 2005. Workshop participants examined knowledge and approaches to learning about the bacterial inhabitants of the human gut, the best known host-microbe system, as well as findings from studies of microbial communities associated with other mammals, fish, plants, soil, and insects. The perspective adopted by this workshop is one that recognizes the breadth and diversity of host-microbe relationships beyond those relative few that result in overt disease. Included in this summary are the reports and papers of individuals participating in the Forum as well as the views of the editors.
Download or read book Microbiology Australia written by and published by . This book was released on 2006-09 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Microbiology Australia written by and published by . This book was released on 2006-09 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Microbiology Australia written by and published by . This book was released on 2006-09 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NETosis At the Intersection of Cell Biology Microbiology and Immunology written by Mariana J. Kaplan and published by Frontiers E-books. This book was released on 2013-08-08 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: NETosis is a unique form of cell death that is characterized by the release of decondensed chromatin and granular contents to the extracellular space. The initial observation of NETosis placed the process within the context of the innate immune response to infections. Neutrophils, the most numerous leukocytes that arrive quickly at the site of an infection, were the first cell type shown to undergo extracellular trap formation. However, subsequent studies showed that other granulocytes are also capable of releasing nuclear chromatin following stimulation. The extracellular chromatin acts to immobilize microbes and prevent their dispersal in the host. Bacterial breakdown products and inflammatory stimuli induce NETosis and the release of NETs requires enzyme activities. Histones in NET chromatin become modified by peptidylarginine deiminase 4 (PAD4) and cleaved at specific sites by proteases. NETs serve for attachment of bactericidal enzymes including myeloperoxidase, leukocyte proteases, and the cathelicidin LL-37. While the benefit of NETs in an infection appears clear, NETs also figure prominently at the center of various pathologic states. Therefore, it is important for NETs to be efficiently cleared; else digestive enzymes may gain access to tissues where inflammation takes place. Persistent NET exposure at sites of inflammation may lead to a further complication: NET antigens may provoke acquired immune responses and, over time, could initiate autoimmune reactions. Recent studies identified aberrant NET synthesis and/or clearance in inflammatory/autoimmune conditions such as systemic lupus erythematosus (SLE), psoriasis, ANCA-positive vasculitis, gout and Felty’s syndrome. In the case of SLE, for example, it appears that LL-37 exposed in the NETs may be a significant trigger of type I Interferon responses in this disease. Recent evidence also implicates aberrant NET formation in the development of endothelial damage, atherosclerosis and thrombosis. NETosis is thus of interest to researchers who investigate innate immune responses, host-pathogen interactions, chronic inflammatory disorders, cell and vascular biology, biochemistry, and autoimmunity. As we approach the 10-year-anniversary of the initial discovery of NETosis, it is useful and timely to review the so far identified mechanisms and pathways of NET formation, their role in bacterial and fungal defense and their putative importance as inducers of autoimmune responses. We look forward to a rich and rigorous discussion of these and related issues that benefit from interdisciplinary approaches, collaborations and exciting discoveries.
Download or read book New advances in the biology and pathogenesis of free living amoebae written by Isabel Marcelino and published by Frontiers Media SA. This book was released on 2024-05-06 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt: Free-living amoebae (FLA) are fascinating unicellular eukaryotes, living freely in soil and freshwater habitats and feeding mainly on bacteria. Under stressful conditions, they can transform from a motile, metabolically active, and replicative trophozoite to a “dormant” and resistant cyst. Some FLA can be pathogenic to humans such as Acanthamoeba, Balamuthia, Naegleria, and Sappinia causing rare but fatal infection in humans. FLA are also known to be carriers of pathogenic microorganisms, but few information is currently available on the natural bacteria of FLA and how various bacteria avoid phagocytosis/predation by these specific types of amoebae. There is an imperious need to draw more attention to this group of microorganisms and for this we seek submissions that address advancements in the biology and pathogenesis of FLAs.
