scholarly journals Intraclonal polymorphism in the bacterium Streptomyces ambofaciens ATCC23877: evidence for a high degree of heterogeneity of the wild type clones

1999 ◽  
Vol 430 (1) ◽  
pp. 75-85 ◽  
Author(s):  
Patricia Martin ◽  
Annie Dary ◽  
Axelle André ◽  
Gilles Fischer ◽  
Pierre Leblond ◽  
...  
Keyword(s):  
Wild Type ◽  
Streptomyces Ambofaciens ◽  
High Degree ◽  
Degree Of Heterogeneity

scholarly journals Precision radiogenomics: fusion biopsies to target tumour habitats in vivo

2021 ◽  
Author(s):  
Mireia Crispin-Ortuzar ◽  
Evis Sala
Keyword(s):  
Ovarian Cancer ◽  
Ct Scans ◽  
High Grade ◽  
Serous Ovarian Cancer ◽  
High Degree ◽  
Degree Of Heterogeneity

SummaryHigh-grade serous ovarian cancer lesions display a high degree of heterogeneity on CT scans. We have recently shown that regions with distinct imaging profiles can be accurately biopsied in vivo using a technique based on the fusion of CT and ultrasound scans.

scholarly journals Prevalence and Impact of Atrial Fibrillation in Hospitalized Patients with COVID-19: A Systematic Review and Meta-Analysis

2021 ◽  
Vol 10 (11) ◽  
pp. 2490
Author(s):  
Giulio Francesco Romiti ◽  
Bernadette Corica ◽  
Gregory Y. H. Lip ◽  
Marco Proietti
Keyword(s):  
Atrial Fibrillation ◽  
Systematic Review ◽  
Meta Analysis ◽  
Geographical Location ◽  
Treatment Strategies ◽  
Cardiovascular Complications ◽  
Risk Of Death ◽  
All Cause Mortality ◽  
High Degree ◽  
Degree Of Heterogeneity

Background: In patients with COVID-19, cardiovascular complications are common and associated with poor prognosis. Among these, an association between atrial fibrillation (AF) and COVID-19 has been described; however, the extent of this relationship is unclear. The aim of this study is to investigate the epidemiology of AF in COVID-19 patients and its impact on all-cause mortality. Methods: A systematic review and meta-analysis were performed and reported according to PRISMA guidelines, and a protocol for this study was registered on PROSPERO (CRD42021227950). PubMed and EMBASE were systematically searched for relevant studies. A random-effects model was used to estimate pooled odds ratios (OR) and 95% confidence intervals (CI). Results: Overall, 31 studies were included in the analysis, with a total number of 187,716 COVID-19 patients. The prevalence of AF was found to be as high as 8% of patients with COVID-19 (95% CI: 6.3–10.2%, 95% prediction intervals (PI): 2.0–27.1%), with a high degree of heterogeneity between studies; a multiple meta-regression model including geographical location, age, hypertension, and diabetes showed that these factors accounted for more than a third of the heterogeneity. AF COVID-19 patients were less likely to be female but more likely older, hypertensive, and with a critical status than those without AF. Patients with AF showed a significant increase in the risk of all-cause mortality (OR: 3.97, 95% CI: 2.76–5.71), with a high degree of heterogeneity. A sensitivity analysis focusing on new-onset AF showed the consistency of these results. Conclusions: Among COVID-19 patients, AF is found in 8% of patients. AF COVID-19 patients are older, more hypertensive, and more likely to have a critical status. In COVID-19 patients, AF is associated with a 4-fold higher risk of death. Further studies are needed to define the best treatment strategies to improve the prognosis of AF COVID-19 patients.

scholarly journals Similarly Lethal Strains of Extraintestinal Pathogenic Escherichia coli Trigger Markedly Diverse Host Responses in a Zebrafish Model of Sepsis

mSphere ◽  
2016 ◽  
Vol 1 (2) ◽  
Author(s):  
Amelia E. Barber ◽  
Brittany A. Fleming ◽  
Matthew A. Mulvey
Keyword(s):  
The United States ◽  
Host Responses ◽  
Inflammatory Condition ◽  
Therapeutic Approaches ◽  
Zebrafish Model ◽  
Life Threatening ◽  
High Degree ◽  
Care Costs ◽  
Variable Impact ◽  
Degree Of Heterogeneity

ABSTRACT Sepsis is a life-threatening systemic inflammatory condition that is initiated by the presence of microorganisms in the bloodstream. In the United States, sepsis due to ExPEC and other pathogens kills well over a quarter of a million people each year and is associated with tremendous health care costs. A high degree of heterogeneity in the signs and symptomology of sepsis makes this disease notoriously difficult to effectively diagnose and manage. Here, using a zebrafish model of sepsis, we find that similarly lethal but genetically distinct ExPEC isolates can elicit notably disparate host responses. These variances are in part due to differences in the levels and types of flagellin that are expressed by the infecting ExPEC strains. A better understanding of the variable impact that bacterial factors like flagellin have on host responses during sepsis could lead to improved diagnostic and therapeutic approaches to these often deadly infections. In individuals with sepsis, the infecting microbes are commonly viewed as generic inducers of inflammation while the host background is considered the primary variable affecting disease progression and outcome. To study the effects of bacterial strain differences on the maladaptive immune responses that are induced during sepsis, we employed a novel zebrafish embryo infection model using extraintestinal pathogenic Escherichia coli (ExPEC) isolates. These genetically diverse pathogens are a leading cause of sepsis and are becoming increasingly dangerous because of the rise of multidrug-resistant strains. Zebrafish infected with ExPEC isolates exhibit many of the pathophysiological features seen in septic human patients, including dysregulated inflammatory responses (cytokine storms), tachycardia, endothelial leakage, and progressive edema. However, only a limited subset of ExPEC isolates can trigger a sepsis-like state and death of the host when introduced into the bloodstream. Mirroring the situation in human patients, antibiotic therapy reduced ExPEC titers and improved host survival rates but was only effective within limited time frames that varied, depending on the infecting pathogen. Intriguingly, we find that phylogenetically distant but similarly lethal ExPEC isolates can stimulate markedly different host transcriptional responses, including disparate levels of inflammatory mediators. These differences correlate with the amounts of bacterial flagellin expression during infection, as well as differential activation of Toll-like receptor 5 by discrete flagellar serotypes. Altogether, this work establishes zebrafish as a relevant model of key aspects of human sepsis and highlights the ability of genetically distinct ExPEC isolates to induce divergent host responses independently of baseline host attributes. IMPORTANCE Sepsis is a life-threatening systemic inflammatory condition that is initiated by the presence of microorganisms in the bloodstream. In the United States, sepsis due to ExPEC and other pathogens kills well over a quarter of a million people each year and is associated with tremendous health care costs. A high degree of heterogeneity in the signs and symptomology of sepsis makes this disease notoriously difficult to effectively diagnose and manage. Here, using a zebrafish model of sepsis, we find that similarly lethal but genetically distinct ExPEC isolates can elicit notably disparate host responses. These variances are in part due to differences in the levels and types of flagellin that are expressed by the infecting ExPEC strains. A better understanding of the variable impact that bacterial factors like flagellin have on host responses during sepsis could lead to improved diagnostic and therapeutic approaches to these often deadly infections. Podcast: A podcast concerning this article is available.

scholarly journals Application of the polygon method to analyze the differentiation of the regions of the Volga federal district by the level of e-business development

2021 ◽  
Vol 270 ◽  
pp. 01025
Author(s):  
Marina Bikeeva ◽  
Evgeniya Sysoeva
Keyword(s):  
Federal District ◽  
Software Tools ◽  
Business Development ◽  
Special Software ◽  
The Republic ◽  
Integral Assessment ◽  
High Degree ◽  
Polygon Method ◽  
Nizhny Novgorod Region ◽  
Degree Of Heterogeneity

The materials of the article contain an integral assessment of the level of development of e-business on the example of the regions of the Volga Federal District (VFD). As a result of calculating the private and local ranks of the values of the selected criteria, fourteen polygons of the level of e-business development were built by the number of regions in the district. The results obtained make it possible to ascertain the existence of a high degree of heterogeneity of the VFD regions in terms of the level of e-business development. The leading regions include the Republic of Tatarstan, the Perm Territory, and the Nizhny Novgorod Region. The outsider regions - the Republic of Mari El, the Republic of Mordovia and the Kirov region - are characterized by a low share of organizations that used the capabilities of the Intranet and Extranet in their activities, the lack of special software tools for managing sales of goods (works, services), limited use of software, in particular, ERP-, CRM and SCM-systems.

A mutation in an exbD gene reduces tagetitoxin production by Pseudomonas syringae pv. tagetis

2006 ◽  
Vol 52 (11) ◽  
pp. 1027-1035 ◽  
Author(s):  
Hyesuk Kong ◽  
Cheryl D Patterson ◽  
Robin E Mitchell ◽  
Jeffrey S Buyer ◽  
M Catherine Aime ◽  
...  
Keyword(s):  
Pseudomonas Syringae ◽  
Wild Type Strain ◽  
Efflux Pump ◽  
Wild Type ◽  
Chain Reaction ◽  
Sequence Identity ◽  
Mutant Strains ◽  
Tonb System ◽  
Polymerase Chain ◽  
High Degree

A mutant of Pseudomonas syringae pv. tagetis EB037 with limited ability to produce tagetitoxin was isolated after transposon mutagenesis and the mutation was characterized. The mutation occurred in a gene with a high degree of sequence identity to exbD. exbD is contiguous with tonB and exbB upstream and with a gene for a TonB-dependent receptor downstream. Using reverse transcription – polymerase chain reaction with RNA from the wild-type and exbD mutant strains, we demonstrated that the mutation in exbD did not have a polar affect on the expression of downstream genes. The exbD mutant was able to grow well in conditions where iron is not freely available. Siderophore production by the exbD mutant was similar to that of the wild-type strain. We conclude that the mutation in exbD disrupts tagetitoxin production without compromising iron metabolism. The results indicate that tagetitoxin export by P. syringae pv. tagetis involves an efflux pump that requires a functional TonB system that is not essential for normal iron metabolism.Key words: Pseudomonas syringae pv. tagetis, Pseudomonas putida, tagetitoxin, exbD, exbB, tonB, TonB system, Helianthus annuus L.

scholarly journals Accountability and Reporting in the Fight against Corruption: Preliminary Evidences from the Italian Setting

2017 ◽  
Vol 12 (4) ◽  
pp. 1
Author(s):  
Rosanna Spanò ◽  
Luca Ferri ◽  
Clelia Fiondella ◽  
Marco Maffei
Keyword(s):  
Content Analysis ◽  
Research Question ◽  
National Context ◽  
Reporting Practices ◽  
High Degree ◽  
Poor Reporting ◽  
Degree Of Heterogeneity ◽  
Regional Governments

This paper aims to explain how Italian Regional Governments reacted to the introduction of the Anti-Corruption Plans in order to understand the degree of thoroughness. To answer the research question 20 Anti-Corruption Plans prepared by Italian Regional Governments for the years 2013-2016. The plans were examined using a meaning-oriented content analysis. This analysis allows us to detect the degree of compliance with the National Anticorruption Plan (NAP). Also we investigated the characteristics of the information, as well as the degree of thoroughness of the reports. Our findings highlight the existence of high degree of heterogeneity in the Anti corruption plans that characterises the national context. Also, our findings reveal the existence of a wide presence of regions employing poor reporting practices.

Contribution of intermediate filaments to cell stiffness, stiffening, and growth

2000 ◽  
Vol 279 (1) ◽  
pp. C188-C194 ◽  
Author(s):  
Ning Wang ◽  
Dimitrije Stamenović
Keyword(s):  
Mechanical Properties ◽  
Applied Stress ◽  
Extended Period ◽  
Direct Consequence ◽  
Cell Stiffness ◽  
Cell Integrity ◽  
Wild Type ◽  
The Difference ◽  
High Degree

It has been shown previously that intermediate filament (IF) gels in vitro exhibit stiffening at high-applied stress, and it was suggested that this stiffening property of IFs might be important for maintaining cell integrity at large deformations (Janmey PA, Evtenever V, Traub P, and Schliwa M, J Cell Biol 113: 155–160, 1991). In this study, the contribution of IFs to cell mechanical behavior was investigated by measuring cell stiffness in response to applied stress in adherent wild-type and vimentin-deficient fibroblasts using magnetic twisting cytometry. It was found that vimentin-deficient cells were less stiff and exhibited less stiffening than wild-type cells, except at the lowest applied stress (10 dyn/cm2) where the difference in the stiffness was not significant. Similar results were obtained from measurements on wild-type fibroblasts and endothelial cells after vimentin IFs were disrupted by acrylamide. If, however, cells were plated over an extended period of time (16 h), they exhibited a significantly greater stiffness before than after acrylamide, even at the lowest applied stress. A possible reason could be that the initially slack IFs became fully extended due to a high degree of cell spreading and thus contributed to the transmission of mechanical stress across the cell. Taken together, these findings were consistent with the notion that IFs play important roles in the mechanical properties of the cell during large deformation. The experimental data also showed that depleting or disrupting IFs reduced, but did not entirely abolish, cell stiffening. This residual stiffening might be attributed to the effect of geometrical realignment of cytoskeletal filaments in the direction of applied load. It was also found that vimentin-deficient cells exhibited a slower rate of proliferation and DNA synthesis than wild-type cells. This could be a direct consequence of the absence of the intracellular IFs that may be necessary for efficient mediation of mechanical signals within the cell. Taken together, results of this study suggest that IFs play important roles in the mechanical properties of cells and in cell growth.

Role of glutamine synthetase in phenazine antibiotic production by Pantoea agglomerans Eh1087

2004 ◽  
Vol 50 (10) ◽  
pp. 877-881 ◽  
Author(s):  
Matthew D Galbraith ◽  
Stephen R Giddens ◽  
H Khris Mahanty ◽  
Bruce Clark
Keyword(s):  
Glutamine Synthetase ◽  
Antibiotic Production ◽  
Amino Acid Sequences ◽  
Pantoea Agglomerans ◽  
Wild Type ◽  
Isotopic Labelling ◽  
High Degree ◽  
Degree Of Similarity ◽  
Isotopic Labelling Experiments

Pantoea agglomerans strain Eh1087 produces the phenazine antibiotic D-alanylgriseoluteic acid. A glutamine auxotroph harboring an insertion in a putative glnA gene was obtained by transposon-mutagenesis of Eh1087 that produced less D-alanylgriseoluteic acid than the parental strain (strain Eh7.1). Cosmids encoding the Eh1087 glnA were isolated by their ability to complement the mutant for prototrophy. The role of the Eh1087 glnA locus was functionally confirmed by complementation of an Escherichia coli glnA mutant. Analysis of the nucleotide and deduced amino acid sequences of the Eh1087 glnA gene indicated a high degree of similarity to the glnA genes and glutamine synthetase enzymes of other Enterobacteriaceae. Isotopic labelling experiments with 15N-labelled ammonium sulfate demonstrated that wild-type Eh1087 incorporated 15N into griseoluteic acid more readily than the glnA mutant Eh7.1. We conclude that the 2 nitrogens in the phenazine nucleus originate from glutamine and the intracellular glutamine synthesized by Eh1087 is a source of the phenazine nucleus nitrogens even in glutamine-rich environments.Key words: phenazine, Pantoea, Erwinia, glutamine synthetase, biosynthesis.

scholarly journals An Internal Motor Kinesin Is Associated with the Golgi Apparatus and Plays a Role in Trichome Morphogenesis in Arabidopsis

2005 ◽  
Vol 16 (2) ◽  
pp. 811-823 ◽  
Author(s):  
Ling Lu ◽  
Yuh-Ru Julie Lee ◽  
Ruiqin Pan ◽  
Julin N. Maloof ◽  
Bo Liu
Keyword(s):  
Golgi Apparatus ◽  
Cell Cortex ◽  
Wild Type ◽  
Internal Motor ◽  
Kinesin Superfamily ◽  
High Degree ◽  
Mutant Cells ◽  
Transport Molecules ◽  
Degree Of Similarity ◽  
Sequence Similarities

Members of the kinesin superfamily are microtubule-based motor proteins that transport molecules/organelles along microtubules. We have identified similar internal motor kinesins, Kinesin-13A, from the cotton Gossypium hirsutum and Arabidopsis thaliana. Their motor domains share high degree of similarity with those of internal motor kinesins of animals and protists in the MCAK/Kinesin13 subfamily. However, no significant sequence similarities were detected in sequences outside the motor domain. In Arabidopsis plants carrying the T-DNA knockout kinesin-13a-1 and kinesin-13a-2 mutations at the Kinesin-13A locus, >70% leaf trichomes had four branches, whereas wild-type trichomes had three. Immunofluorescent results showed that AtKinesin-13A and GhKinesin-13A localized to entire Golgi stacks. In both wild-type and kinesin-13a mutant cells, the Golgi stacks were frequently associated with microtubules and with actin microfilaments. Aggregation/clustering of Golgi stacks was often observed in the kinesin-13a mutant trichomes and other epidermal cells. This suggested that the distribution of the Golgi apparatus in cell cortex might require microtubules and Kinesin-13A, and the organization of Golgi stacks could play a regulatory role in trichome morphogenesis. Our results also indicate that plant kinesins in the MCAK/Kinesin-13 subfamily have evolved to take on different tasks than their animal counterparts.

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