scholarly journals Prophages in the infant gut are largely induced, and may be functionally relevant to their hosts.

2021 ◽  
Author(s):  
Tamsin A Redgwell ◽  
Jonathan Thorsen ◽  
Marie-Agnes Petit ◽  
Ling Deng ◽  
Gisle A Vestergaard ◽  
...  
Keyword(s):  
Functional Annotation ◽  
Biological Entity ◽  
Host Bacterium ◽  
Capsular Polysaccharides ◽  
Disease States ◽  
Bacterial Microbiome ◽  
Key Drivers ◽  
The Individual ◽  
And Function ◽  
Susceptible Subpopulations

Background: Bacteriophages are the most abundant biological entity on the planet, and are key components of any ecosystem they are present in. The gut virome is increasingly being implicated in disease states although these studies largely focus on lytic phages in adults. Here we identify prophages from a large infant cohort and investigate their potential functions. Results: We identified 10645 vOTUs from 662 metagenomes. No core virome was found: the most prevalent vOTU was identified in 70% of the samples. The most abundant and prevalent group of phages are a novel group closely related to Bacteroides phage Hanky p00. Functional annotation of this group revealed the presence of genes in the dDTP-L-rhamnose pathway, possibly involved in the production of capsular polysaccharides. We also found an abundance of diversity generating retroelements in the phages. Additionally, paired virome data allowed us to show that the majority of prophages are induced in at least one sample and that this is not affected by the use of antibiotics in the 4 weeks prior to sampling. Conclusions: Prophages in the infant gut are largely unique to the individual and not shared. Most of them appear to be induced and so may be key drivers in shaping the bacterial microbiome. The most abundant group of phages are novel, and possess elements that may allow them to maintain differentially susceptible subpopulations of their host bacterium; whilst also containing diversity generating retroelements that could expand their host range. Prophages are important components of the infant gut that may have far reaching influences on the composition and function of the microbiome.

Narrow is the Gate to Utopia

Moreana ◽  
2012 ◽  
Vol 49 (Number 187- (1-2) ◽  
pp. 207-226
Author(s):  
Marie-Claire Phélippeau
Keyword(s):  
Social Construction ◽  
Free Will ◽  
Religious Toleration ◽  
Individual Liberty ◽  
The Reformation ◽  
The Individual ◽  
And Function

This study examines the notions of pleasure, individual liberty and consensus in Thomas More’s Utopia. The paradox inherent in Utopia, written before the Reformation, is especially visible in the affirmation of religious toleration coexisting with the need for a strict supervision of the citizens. The dream of an ideal republic is based on a Pauline vision of man which defines the individual mainly as a sinner. Consequently, it is the duty of the republic’s rulers to guide the citizens and establish a consensus. This study tries to determine the part left to the individual’s free will and examines the nature and function of the structures that are supposed to ensure the happiness of each one and of the whole community. The notion of moral hierarchy is asserted as the linchpin of the Utopian social construction.

Ecosystems processes

2018 ◽  
Author(s):  
Karen J. Esler ◽  
Anna L. Jacobsen ◽  
R. Brandon Pratt
Keyword(s):  
Ecosystem Function ◽  
Mineral Nutrients ◽  
Structure And Function ◽  
Water Dynamics ◽  
Ecosystem Level ◽  
Key Drivers ◽  
And Function ◽  
Mediterranean Type Ecosystems

Ecosystems are assemblages of organisms interacting with one another and their environment (Chapter 1). Key to the functioning of ecosystems is the flow of energy, carbon, mineral nutrients, and water in these systems. The numerous processes involved are chiefly driven by climate, soil, and fire (Chapter 2). In cases where the key drivers are the same in different areas, then ecosystems should converge in their structure and function, which has been a motivation for comparing across mediterranean-type climate (MTC) regions. Convergence of MTC regions has been evaluated, but such comparisons at the ecosystem level are challenging because ecosystems are complex and dynamic entities. Here we review carbon, nutrient, and water dynamics of mediterranean-type ecosystems in the context of ecosystem function. As nutrients in soils are low in some MTC regions, we review how this has led to unique adaptations to meet this challenge.

scholarly journals Adolescent and adult laryngotracheal stenosis: a review

2021 ◽  
Vol 37 (1) ◽  
Author(s):  
Gerhard Johan Klopper ◽  
Oladele Vincent Adeniyi ◽  
Kate Stephenson
Keyword(s):  
Intensive Care ◽  
Past Century ◽  
Main Body ◽  
Laryngotracheal Stenosis ◽  
Airway Protection ◽  
Interventional Pulmonology ◽  
The Past ◽  
Airway Emergency ◽  
The Individual ◽  
And Function

Abstract Background The larynx has multiple composite functions which include phonation, airway protection, and sensory control of respiration. Stenosis of the larynx and trachea were first recorded by O’Dwyer in 1885 and by Colles in 1886, respectively. Initially, the aetiology of laryngotracheal stenosis was predominantly infective. Currently, the leading cause is iatrogenic injury to the laryngotracheal complex secondary to prolonged ventilation in an intensive care unit. Main body Laryngotracheal stenosis is a complex and diverse disease. It poses a major challenge to the surgeon and can present as an airway emergency. Management typically demands the combined involvement of various disciplines including otorhinolaryngology, cardiothoracic surgery, anaesthesiology, interventional pulmonology, and radiology. Both the disease and its management can impact upon respiration, voice, and swallowing. The incidence of iatrogenic laryngotracheal stenosis has reflected the evolution of airway and intensive care whilst airway surgery has advanced concurrently over the past century. Correction of laryngotracheal stenosis requires expansion of the airway lumen; this is achieved by either endoscopic or open surgery. We review the relevant basic science, aetiopathogenesis, diagnosis, management, and treatment outcomes of LTS. Conclusion The choice of surgical procedure in the management of laryngotracheal stenosis is often dictated by the individual anatomy and function of the larynx and trachea, together with patient factors and available facilities. Regardless of how the surgeon chooses to approach these lesions, prevention of iatrogenic laryngotracheal damage remains of primary importance.

Studies on the structure and function of the mammalian testis V. Steroid metabolism by isolated interstitium and seminiferous tubules of the human testis

1974 ◽  
Vol 186 (1083) ◽  
pp. 99-120 ◽  
Keyword(s):  
Metabolic Activity ◽  
General Pattern ◽  
Steroid Metabolism ◽  
Human Testis ◽  
Clinical Aspects ◽  
Seminiferous Tubules ◽  
Bicarbonate Buffer ◽  
The Media ◽  
The Individual ◽  
And Function

Tissue was obtained from the testes of three men, two in the age range 72-75 years (subjects A and B) and one aged 25 years (subject C). Parts of the testes were dissected to obtain samples of interstitium and tubules. The individual components and whole tissue were each incubated with equimolar concentrations of [7 α - 3 H]pregnenolone and [4- 14 C]progesterone in Krebs-Ringer bicarbonate buffer pH 7.4, at 35 °C with the addition of glucose but without cofactors. Some incubations were carried out with the substrates [4- 14 C]androstenedione and [7 α - 3 H]testosterone. The media were extracted both at various time intervals throughout the incubation for a kinetic study of the metabolic activity and after a fixed interval of time at the end of the incubations. In some incubations with whole tissue both media and tissue were extracted. Both the tubules and interstitium displayed steroid metabolic activity. Qualitatively they yielded the same range of metabolites, one series leading to the formation of testosterone (∆ 5 pathway) and the other to a variety of C 21 compounds as represented by 5 α -pregnan-3 β -ol-20-one. With similar amounts of tissue there was little difference in the yields of the main products formed by the tubules as compared with those formed by the interstitium; in incubations with [4- 14 C]androstenedione the rate of conversion to [ 14 C ]testosterone by the tubules greatly exceeded that due to the interstitium. Marked differences were found in the pattern of steroid metabolism by whole tissue as compared to the general pattern presented by the corresponding tubules and interstitium. It is concluded that the seminiferous tubules and interstitium of the human testis are both capable of steroid metabolism and hence that whole tissue incubations alone are of limited value and could give rise to misleading data. Some clinical aspects of the results are briefly discussed.

scholarly journals Postprenylation CAAX Processing Is Required for Proper Localization of Ras but Not Rho GTPases

2005 ◽  
Vol 16 (4) ◽  
pp. 1606-1616 ◽  
Author(s):  
David Michaelson ◽  
Wasif Ali ◽  
Vi K. Chiu ◽  
Martin Bergo ◽  
Joseph Silletti ◽  
...  
Keyword(s):  
Posttranslational Modifications ◽  
Protein Trafficking ◽  
Rho Gtpases ◽  
Ras Proteins ◽  
Rho Proteins ◽  
Carboxyl Methylation ◽  
C Terminus ◽  
Individual Contributions ◽  
The Individual ◽  
And Function

The CAAX motif at the C terminus of most monomeric GTPases is required for membrane targeting because it signals for a series of three posttranslational modifications that include isoprenylation, endoproteolytic release of the C-terminal– AAX amino acids, and carboxyl methylation of the newly exposed isoprenylcysteine. The individual contributions of these modifications to protein trafficking and function are unknown. To address this issue, we performed a series of experiments with mouse embryonic fibroblasts (MEFs) lacking Rce1 (responsible for removal of the –AAX sequence) or Icmt (responsible for carboxyl methylation of the isoprenylcysteine). In MEFs lacking Rce1 or Icmt, farnesylated Ras proteins were mislocalized. In contrast, the intracellular localizations of geranylgeranylated Rho GTPases were not perturbed. Consistent with the latter finding, RhoGDI binding and actin remodeling were normal in Rce1- and Icmt-deficient cells. Swapping geranylgeranylation for farnesylation on Ras proteins or vice versa on Rho proteins reversed the differential sensitivities to Rce1 and Icmt deficiency. These results suggest that postprenylation CAAX processing is required for proper localization of farnesylated Ras but not geranygeranylated Rho proteins.

scholarly journals Advances in high-density lipoprotein physiology: surprises, overturns, and promises

2016 ◽  
Vol 310 (1) ◽  
pp. E1-E14 ◽  
Author(s):  
Caterina Constantinou ◽  
Eleni A. Karavia ◽  
Eva Xepapadaki ◽  
Peristera-Ioanna Petropoulou ◽  
Eugenia Papakosta ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Fatty Liver Disease ◽  
Metabolic Disorders ◽  
Density Lipoprotein ◽  
Pulmonary Diseases ◽  
Brain Disorders ◽  
Nonalcoholic Fatty Liver ◽  
Disease States ◽  
And Function

Emerging evidence strongly supports that changes in the HDL metabolic pathway, which result in changes in HDL proteome and function, appear to have a causative impact on a number of metabolic disorders. Here, we provide a critical review of the most recent and novel findings correlating HDL properties and functionality with various pathophysiological processes and disease states, such as obesity, type 2 diabetes mellitus, nonalcoholic fatty liver disease, inflammation and sepsis, bone and obstructive pulmonary diseases, and brain disorders.

The Tegument and Associated Structures of Fasciola Hepatica

1963 ◽  
Vol s3-104 (68) ◽  
pp. 505-512
Author(s):  
L. T. THREADGOLD
Keyword(s):  
Electron Microscopy ◽  
Surface Layer ◽  
Light Microscopy ◽  
Fasciola Hepatica ◽  
Golgi Bodies ◽  
New Knowledge ◽  
Pinocytotic Vesicles ◽  
The Individual ◽  
And Function ◽  
Internal Level

The cuticle of light microscopy is shown by electron microscopy to be a surface layer of protoplasm which is an extension of areas of nucleated protoplasm lying deep in the parenchyma. The cuticle therefore exists at two levels. The external level is syncytial, consisting of plateaux separated by branching valleys. This level contains apical pinocytotic vesicles, numerous mitochondria, endoplasmic membranes, large basal and other vacuoles, and dense spines. Tube-like evaginations from the base of the external level connect it to the individual areas of flask-shaped protoplasm which compose the internal level. Each of these areas of protoplasm contains a nucleus, great numbers of mitochondria, some vacuoles and diffuse inclusions, and the Golgi bodies. The histochemistry and function of the cuticle is discussed in the light of this new knowledge of cuticular ultrastructure, and a comparison is made between the cuticle of Cestoda and Trematoda.

Effect of EPS on biofilm structure and function as revealed by an individual-based model of biofilm growth

2001 ◽  
Vol 43 (6) ◽  
pp. 135-135 ◽  
Author(s):  
J.-U. Kreft ◽  
J. W. Wimpenny
Keyword(s):  
Dimensional Space ◽  
Three Dimensional ◽  
Structure And Function ◽  
Individual Based Model ◽  
Biofilm Growth ◽  
Rate Dependent ◽  
Binding Forces ◽  
The Individual ◽  
And Function ◽  
Biofilm Structure

We have simulated a nitrifying biofilm with one ammonia and one nitrite oxidising species in order to elucidate the effect of various extracellular polymeric substance (EPS) production scenarios on biofilm structure and function. The individual-based model (IbM) BacSim simulates diffusion of all substrates on a two-dimensional lattice. Each bacterium is individually simulated as a sphere of given size in a continuous, three-dimensional space. EPS production kinetics was described by a growth rate dependent and an independent term (Luedeking-Piret equation). The structure of the biofilm was dramatically influenced by EPS production or capsule formation. EPS production decreased growth of producers and stimulated growth of non-producers because of the energy cost involved. For the same reason, EPS accumulation can fall as its rate of production increases. The patchiness and roughness of the biofilm decreased and the porosity increased due to EPS production. EPS density was maximal in the middle of the vertical profile. Introduction of binding forces between like cells increased clustering.

scholarly journals Nutritional demands in acute and chronic illness

2003 ◽  
Vol 62 (4) ◽  
pp. 777-781 ◽  
Author(s):  
Rosemary A. Richardson ◽  
H. Isobel M. Davidson
Keyword(s):  
Energy Expenditure ◽  
Inflammatory Response ◽  
Energy Homeostasis ◽  
Negative Energy ◽  
Disease States ◽  
Energy Needs ◽  
Sufficient Energy ◽  
Effective Treatment Modality ◽  
The Individual

Common to both acute and chronic disease are disturbances in energy homeostasis, which are evidenced by quantitative and qualitative changes in dietary intake and increased energy expenditure. Negative energy balance results in loss of fat and lean tissue. The management of patients with metabolically-active disease appears to be simple; it would involve the provision of sufficient energy to promote tissue accretion. However, two fundamental issues serve to prevent nutritional demands in disease being met. The determination of appropriate energy requirements relies on predictive formulae. While equations have been developed for critically-ill populations, accurate energy prescribing in the acute setting is uncommon. Only 25–32% of the patients have energy intakes within 10% of their requirements. Clearly, the variation in energy expenditure has led to difficulties in accurately defining the energy needs of the individual. Second, the acute inflammatory response initiated by the host can have profound effects on ingestive behaviour, but this area is poorly understood by practising clinicians. For example, nutritional targets have been set for specific disease states, i.e. pancreatitis 105–147 KJ (25–35 kcal)/kg; chronic liver disease 147–168 kj (35–40 kcl)/kg, but given the alterations in gut physiology that accompany the acute-phase response, targets are unlikely to be met. In cancer cachexia attenuation of the inflammatory response using eicosapentaenoic acid results in improved nutritional intake and status. This strategy poses an attractive proposition in the quest to define nutritional support as a clinically-effective treatment modality in other disorders.

scholarly journals Anisotropic Cardiac Conduction

2020 ◽  
Vol 9 (4) ◽  
pp. 202-210
Author(s):  
Irum Kotadia ◽  
John Whitaker ◽  
Caroline Roney ◽  
Steven Niederer ◽  
Mark O’Neill ◽  
...  
Keyword(s):  
Gap Junction ◽  
Cardiac Tissue ◽  
Diffusion Tensor ◽  
Interstitial Fibrosis ◽  
Cardiac Conduction ◽  
Principal Mechanism ◽  
Disease States ◽  
And Function ◽  
Anisotropic Conduction

Anisotropy is the property of directional dependence. In cardiac tissue, conduction velocity is anisotropic and its orientation is determined by myocyte direction. Cell shape and size, excitability, myocardial fibrosis, gap junction distribution and function are all considered to contribute to anisotropic conduction. In disease states, anisotropic conduction may be enhanced, and is implicated, in the genesis of pathological arrhythmias. The principal mechanism responsible for enhanced anisotropy in disease remains uncertain. Possible contributors include changes in cellular excitability, changes in gap junction distribution or function and cellular uncoupling through interstitial fibrosis. It has recently been demonstrated that myocyte orientation may be identified using diffusion tensor magnetic resonance imaging in explanted hearts, and multisite pacing protocols have been proposed to estimate myocyte orientation and anisotropic conduction in vivo. These tools have the potential to contribute to the understanding of the role of myocyte disarray and anisotropic conduction in arrhythmic states.

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