The central role of the microbiome in critical illness is supported by a half century of experimental and clinical study. The physiological effects of critical illness and the clinical interventions ...of intensive care substantially alter the microbiome. In turn, the microbiome predicts patients' susceptibility to disease, and manipulation of the microbiome has prevented or modulated critical illness in animal models and clinical trials. This Review surveys the microbial ecology of critically ill patients, presents the facts and unanswered questions surrounding gut-derived sepsis, and explores the radically altered ecosystem of the injured alveolus. The revolution in culture-independent microbiology has provided the tools needed to target the microbiome rationally for the prevention and treatment of critical illness, holding great promise to improve the acute and chronic outcomes of the critically ill.
Numerous studies, dating back nearly a century, have demonstrated that microaspiration is common in healthy, asymptomatic subjects 2-5, and knowledge of the bacterial content of inhaled air is as ...old as germ theory itself 6. Since the first culture-independent report of the healthy lung microbiome 7, more than 30 published studies using molecular techniques for bacterial identification have found evidence of bacteria in the lower airways. ...the community membership of the lung microbiome is altered in disease states.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Though creation and characterization of water soluble luminescent silver nanodots were achieved only in the past decade, a large variety of emitters in diverse scaffolds have been reported. ...Photophysical properties approach those of semiconductor quantum dots, but relatively small sizes are retained. Because of these properties, silver nanodots are finding ever-expanding roles as probes and biolabels. In this
critical review
we revisit the studies on silver nanodots in inert environments and in aqueous solutions. The recent advances detailing their chemical and physical properties of silver nanodots are highlighted with an effort to decipher the relations between their chemical/photophysical properties and their structures. The primary results about their biological applications are discussed here as well, especially relating to their chemical and photophysical behaviours in biological environments (216 references).
The recent advances about the chemical and physical properties of silver nanodots are highlighted with an effort to decipher the relations between their chemical/photophysical properties and their structures. The primary results about their biological applications are discussed as well.
Summary Culture-independent microbiological techniques have shown a previously unappreciated complexity to the bacterial microbiome of the respiratory tract that forces reconsideration of the ...interactions between host, bacteria, and the pathogenesis of exacerbations of chronic lung disease. The composition of the lung microbiome is determined by microbial immigration, elimination, and relative growth rates of its members. All these factors change dramatically in chronic lung disease and further during exacerbations. Exacerbations lack the features of bacterial infections, including increased bacterial burden and decreased diversity of microbial communities. We propose that exacerbations are occasions of respiratory tract dysbiosis—a disorder of the respiratory tract microbial ecosystem with negative effects on host biology. Respiratory tract dysbiosis provokes a dysregulated host immune response, which in turn alters growth conditions for microbes in airways, promoting further dysbiosis and perpetuating a cycle of inflammation and disordered microbiota. Differences in the composition of baseline respiratory tract microbiota might help to explain the so-called frequent-exacerbator phenotype observed in several disease states, and might provide novel targets for therapeutic intervention.
Using 16S rRNA gene sequencing, the authors characterized bacteria detected in endotracheal aspirates collected serially from a large cohort of mechanically ventilated trauma patients. By applying ...rigorous ecologic analyses to this well-characterized cohort, they identified previously undemonstrated relationships between the composition of respiratory microbiota and host factors (smoking status, congestive heart failure, alcohol use), as well as concentrations of concurrently sampled plasma biomarkers of inflammation and alveolar injury. The alveolar ecosystem, normally inhospitable to bacterial reproduction (11), is radically altered in ARDS by the influx of nutrient-rich edema, the establishment of stark oxygen gradients, the surge of bacterial growth-promoting inflammatory molecules (12, 13), and impairment of local host defenses (4, 14). Lung microbiota is related to smoking status and to development of acute respiratory distress syndrome in critically ill trauma patients.
Clustering together: A shuttle‐based fluorogenic cluster transfer, in which silver clusters (SCs) are directly transferred from a low‐molecular‐weight poly(acrylic acid) (PA) shuttle to a ...single‐stranded DNA (ssDNA) tag on the protein of interest (see picture), proceeds with excellent specificity. Upon transfer, the cluster fluorescence increases more than ten times, which provides bright, photostable labeling.
The Microbiome and the Respiratory Tract Dickson, Robert P; Erb-Downward, John R; Martinez, Fernando J ...
Annual review of physiology,
01/2016, Letnik:
78, Številka:
1
Journal Article
Recenzirano
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Although the notion that "the normal lung is free from bacteria" remains common in textbooks, it is virtually always stated without citation or argument. The lungs are constantly exposed to diverse ...communities of microbes from the oropharynx and other sources, and over the past decade, novel culture-independent techniques of microbial identification have revealed that the lungs, previously considered sterile in health, harbor diverse communities of microbes. In this review, we describe the topography and population dynamics of the respiratory tract, both in health and as altered by acute and chronic lung disease. We provide a survey of current techniques of sampling, sequencing, and analysis of respiratory microbiota and review technical challenges and controversies in the field. We review and synthesize what is known about lung microbiota in various diseases and identify key lessons learned across disease states.
The development of culture-independent techniques for microbiological analysis has uncovered the previously unappreciated complexity of the bacterial microbiome at various anatomic sites. The ...microbiome of the lung has relatively less bacterial biomass when compared with the lower gastrointestinal tract yet displays considerable diversity. The composition of the lung microbiome is determined by elimination, immigration, and relative growth within its communities. Chronic lung disease alters these factors. Many forms of chronic lung disease demonstrate exacerbations that drive disease progression and are poorly understood. Mounting evidence supports ways in which microbiota dysbiosis can influence host defense and immunity, and in turn may contribute to disease exacerbations. Thus, the key to understanding the pathogenesis of chronic lung disease may reside in deciphering the complex interactions between the host, pathogen, and resident microbiota during stable disease and exacerbations. In this brief review we discuss new insights into these labyrinthine relationships.
Racial Bias in Pulse Oximetry Measurement Sjoding, Michael W; Dickson, Robert P; Iwashyna, Theodore J ...
New England journal of medicine/The New England journal of medicine,
12/2020, Letnik:
383, Številka:
25
Journal Article
Recenzirano
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The question of whether pulse oximetry measurements vary according to race has not been adequately studied, despite the wide use of this measure in clinical care. In this analysis, Black patients who ...had hypoxemia were more likely to have a normal pulse oximetry reading than were White patients.
Knowledge of the mechanisms for regulating lifespan is advancing rapidly, but lifespan is a complex phenotype and new features are likely to be identified. Here we reveal a novel approach for ...regulating lifespan. Using a genetic or a pharmacological strategy to lower the rate of sphingolipid synthesis, we show that Saccharomyces cerevisiae cells live longer. The longer lifespan is due in part to a reduction in Sch9 protein kinase activity and a consequent reduction in chromosomal mutations and rearrangements and increased stress resistance. Longer lifespan also arises in ways that are independent of Sch9 or caloric restriction, and we speculate on ways that sphingolipids might mediate these aspects of increased lifespan. Sch9 and its mammalian homolog S6 kinase work downstream of the target of rapamycin, TOR1, protein kinase, and play evolutionarily conserved roles in regulating lifespan. Our data establish Sch9 as a focal point for regulating lifespan by integrating nutrient signals from TOR1 with growth and stress signals from sphingolipids. Sphingolipids are found in all eukaryotes and our results suggest that pharmacological down-regulation of one or more sphingolipids may provide a means to reduce age-related diseases and increase lifespan in other eukaryotes.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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