Inflammasome gene expression alterations in Staphylococcus aureus biofilm-associated chronic rhinosinusitis

Background: The role of inflammasomes in chronic inflammation has been the subject of intense research in recent years. Chronic rhinosinusitis (CRS), a persistent inflammatory disease, continues to be investigated hoping that a clearer pathophysiologic description will guide discovery of future treatment modalities. This study investigates the role of inflammasome complexes in CRS patients with Staphylococcus aureus biofilm infection, a key culprit associated with disease severity and recalcitrance. Methodology: Sinonasal tissue samples were collected from CRS patients with (P+) and without (P-) polyps and controls. S. aureus biofilm status was obtained using fluorescence in situ hybridization and classified as biofilm positive (B+) or negative (B-). RNA was analysed using a Human Inflammasome PCR array, profiling the expression of 84 genes involved in inflammasome function. Results: Sixteen samples were obtained: 5 B+P+, 5 B-P- and 6 controls. Comparing B+P+ vs. controls showed the greatest number of differentially expressed genes. In particular, Absent in Melanoma 2 (AIM2) was consistently and significantly up-regulated in the B+P+ vs. B-P- and controls. In contrast, when comparing the B-P- vs. controls, no genes showed significant changes. Conclusion: Our results indicate the involvement of inflammasome complexes and their signalling pathways in CRS patients with polyps and S. aureus biofilms. In particular, AIM2, activated by intracellular double-stranded DNA, is up-regulated in this group, implying that S. aureus may play a role in intracellular triggering of the inflammasome response. Studies with further patient stratification and assessing corresponding protein expression are needed to further characterize the role of inflammasomes in CRS.

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The Role of Al3+-Based Aqueous Electrolytes in the Charge Storage Mechanism of MnOx Cathodes

10.26434/chemrxiv.13272980 ◽

2020 ◽

Author(s):

Véronique Balland ◽

Mickaël Mateos ◽

Kenneth D. Harris ◽

Benoit Limoges

Keyword(s):

Manganese Oxide ◽

Critical Analysis ◽

Charge Storage ◽

Aqueous Electrolytes ◽

Storage Mechanism ◽

Main Charge ◽

Charge Storage Mechanism ◽

The Subject

Rechargeable aqueous aluminium batteries are the subject of growing interest, but the charge storage mechanisms at manganese oxide-based cathodes remain poorly understood with as many mechanisms as studies. Here, we use an original in situ spectroelectrochemical methodology to unambiguously demonstrate that the reversible proton-coupled MnO2-to-Mn2+ conversion is the main charge storage mechanism occurring at MnO2 cathodes over a range of slightly acidic Al3+-based aqueous electrolytes. In Zn/MnO2 assemblies, this mechanism is associated with high gravimetric capacity and discharge potentials, up to 560 mAh·g-1 and 1.76 V respectively, attractive efficiencies (CE > 98.5 % and EE > 80%) and excellent cyclability (> 750 cycles at 10 A·g-1). Finally, we conducted a critical analysis of the data previously published on MnOx cathodes in Al3+-based aqueous electrolytes to conclude on a universal charge storage mechanism, i.e., the reversible electrodissolution/electrodeposition of MnO2.

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Inflammasome gene expression alterations in Staphylococcus aureus biofilm-associated chronic rhinosinusitis

Rhinology Journal ◽

10.4193/rhin13.045 ◽

2013 ◽

Vol 51 (4) ◽

pp. 315-322 ◽

Cited By ~ 9

Author(s):

C. Jardeleza ◽

D. Miljkovic ◽

L. Baker ◽

S. Boase ◽

N.C.W. Tan ◽

...

Keyword(s):

Gene Expression ◽

Staphylococcus Aureus ◽

Chronic Rhinosinusitis ◽

Gene Expression Alterations

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A Novel In Situ Activity Assay for Lysyl Oxidases

10.1101/2021.04.30.442175 ◽

2021 ◽

Author(s):

Huilei Wang ◽

Alan Poe ◽

Lydia Pak ◽

Sandeep Jandu ◽

Kavitha Nandakumar ◽

...

Keyword(s):

Lysyl Oxidase ◽

Activity Assay ◽

Strong Reaction ◽

Tissue Samples ◽

Lysyl Oxidases ◽

Catalytic Function ◽

Elevated Expression ◽

Representative Member

AbstractThe lysyl oxidase family of enzymes (LOXs) catalyze oxidative deamination of lysine side chains on collagen and elastin to initialize cross-linking that is essential for the formation of the extracellular matrix (ECM). Elevated expression of LOXs is highly associated with diverse disease processes. To date, the inability to detect total LOX catalytic function in situ has limited the ability to fully elucidate the role of LOXs in pathobiological mechanisms. Using LOXL2 as a representative member of the LOX family, we developed an in situ activity assay by utilizing the strong reaction between hydrazide and aldehyde to label the LOX-catalyzed allysine (-CHO) residues with biotin-hydrazide. The biotinylated ECM proteins are then labeled via biotin-streptavidin interaction and detected by fluorescence microscopy. This assay detects the total LOX activity in situ for both overexpressed and endogenous LOXs in cells and tissue samples and can be used for studies of LOXs as therapeutic targets.

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Identifying Intracellular Staphylococcus Aureus in Chronic Rhinosinusitis: A Direct Comparison of Techniques

American Journal of Rhinology and Allergy ◽

10.2500/ajra.2012.26.3822 ◽

2012 ◽

Vol 26 (6) ◽

pp. 444-449 ◽

Cited By ~ 11

Author(s):

Neil C.-W. Tan ◽

Hai Bac Tran ◽

Andrew Foreman ◽

Camille Jardeleza ◽

Sarah Vreugde ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Chronic Rhinosinusitis ◽

Imaging Techniques ◽

Simultaneous Detection ◽

Sinus Surgery ◽

Confocal Scanning Laser Microscopy ◽

Tissue Samples ◽

Complementary Techniques ◽

Confocal Scanning Laser ◽

A Prospective Study

Background The emerging concept of intracellular pathogens such as Staphylococcus aureus playing a role in chronic rhinosinusitis (CRS) has led to the development of numerous imaging techniques for their identification. Traditional methods of bacterial culture are not effective at localizing bacteria to the surface or within tissue samples. The aim of this study was to develop and validate a novel imaging technique using confocal scanning laser microscopy (CSLM) coupled with a fluorescence in situ hybridization (FISH) probe and nucleic acid counterstain (propidium iodide [PI]) that allows for simultaneous analysis of S. aureus intracellular status and surface biofilm within whole mucosal samples. Methods A prospective study was performed including 17 patients undergoing endoscopic sinus surgery for CRS. Tissue samples were analyzed with both CSLM-FISH/PI and immunohistochemistry (IHC) for intracellular S. aureus status. Results Using CSLM-FISH/PI intracellular S. aureus was identified in 9/17 (47%) patients and in 7/17 (39%) using IHC. Surface biofilm can be identified with CSLM-FISH/PI in the same piece of tissue; however, deeper imaging to the submucosa is impossible. IHC showed submucosal bacteria in three patients. Conclusion Both CSLM-FISH/PI and IHC are complementary techniques that can be used to identify intracellular S. aureus. CSLM-FISH/PI allows for the simultaneous detection of intracellular status and surface biofilm within the tissue analyzed. IHC has a role in the identification of intracellular and submucosal S. aureus within these tissues. Additional investigation is required to identify the true pathogenic nature of intracellular organisms as well as any relationship to surface biofilm status.

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Reconstitution and visualization of HIV-1 capsid-dependent replication and integration in vitro

Science ◽

10.1126/science.abc8420 ◽

2020 ◽

Vol 370 (6513) ◽

pp. eabc8420 ◽

Cited By ~ 2

Author(s):

Devin E. Christensen ◽

Barbie K. Ganser-Pornillos ◽

Jarrod S. Johnson ◽

Owen Pornillos ◽

Wesley I. Sundquist

Keyword(s):

Cell Extract ◽

Free System ◽

Double Stranded Dna ◽

A Cell ◽

Dna Ends ◽

Hiv 1 ◽

Target Plasmid

During the first half of the viral life cycle, HIV-1 reverse transcribes its RNA genome and integrates the double-stranded DNA copy into a host cell chromosome. Despite progress in characterizing and inhibiting these processes, in situ mechanistic and structural studies remain challenging. This is because these operations are executed by individual viral preintegration complexes deep within cells. We therefore reconstituted and imaged the early stages of HIV-1 replication in a cell-free system. HIV-1 cores released from permeabilized virions supported efficient, capsid-dependent endogenous reverse transcription to produce double-stranded DNA genomes, which sometimes looped out from ruptured capsid walls. Concerted integration of both viral DNA ends into a target plasmid then proceeded in a cell extract–dependent reaction. This reconstituted system uncovers the role of the capsid in templating replication.

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Arteries of the antebrachium and manus of the tokay (Gekko gecko) (Reptilia: Gekkonidae)

Canadian Journal of Zoology ◽

10.1139/z81-085 ◽

1981 ◽

Vol 59 (4) ◽

pp. 573-582 ◽

Cited By ~ 5

Author(s):

Anthony P. Russell

Keyword(s):

Circulatory System ◽

Arterial System ◽

Functional Interpretation ◽

Gekko Gecko ◽

Low Viscosity ◽

Adhesive Pads ◽

The Subject ◽

First Time

The role of the circulatory system in the functioning of the subdigital adhesive pads of geckoes has been the subject of much discussion. However, the morphology and configuration of the blood system in the foot has remained poorly understood, rendering functional interpretation of the blood sinuses simplistic. Here the major arterial vessels of the manus are described for the first time and a discussion of their geometry is presented. Due to the paucity of information concerning the arterial system of the appendages of lizards a description of the major vessels of the antebrachium is also given.The data presented are based on the study of material injected with low-viscosity silicone rubber and then cleared so that vessels may be studied in situ. The data are pertinent to subsequent discussions of the microvasculature of the subdigital lamellae and of reconsiderations of their structure and form.

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Moulds and Staphylococcus aureus enterotoxins are relevant allergens to affect Type 2 inflammation and clinical outcomes in chronic rhinosinusitis patients

ERJ Open Research ◽

10.1183/23120541.00265-2020 ◽

2020 ◽

Vol 6 (4) ◽

pp. 00265-2020

Author(s):

Yoshihiro Kanemitsu ◽

Kensuke Fukumitsu ◽

Ryota Kurokawa ◽

Norihisa Takeda ◽

Yoshiyuki Ozawa ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Clinical Outcomes ◽

Chronic Rhinosinusitis ◽

Specific Ige ◽

Sinus Surgery ◽

Tissue Samples ◽

Asthmatic Patients ◽

Staphylococcus Aureus Enterotoxins ◽

Type 2 Inflammation

BackgroundSensitisation to moulds and Staphylococcus aureus enterotoxins (SEs) is associated with the pathophysiology of both asthma and chronic rhinosinusitis (CRS). The purpose of this study was to clarify the contribution of sensitisation to these allergens to Type 2 inflammation in the blood, nose and the lower airways, and clinical outcomes in CRS patients.MethodsWe prospectively enrolled 56 CRS patients who underwent endoscopic sinus surgery (ESS) (20 with comorbid asthma) and 28 healthy controls between October 2015 and December 2017. CRS patients were followed up for 12 months after surgery. Type 2 inflammation-related biomarkers were analysed using blood, resected tissue samples and sputum. 10 allergens including Alternaria, Aspergillus and SEs were measured. Type 2 inflammation-related biomarkers and clinical outcomes were compared in the stratification with the presence or absence of allergen sensitisation.ResultsSensitisation rate to moulds and SEs in asthmatic patients was increased when changing the cut-off value of specific IgE titre from 0.35 UA·mL−1 to 0.10 UA·mL−1 (1.7- and 4.5-fold, respectively). Moulds and SEs affected the prevalence of asthma and eosinophilic CRS by interacting with each other. All Type 2 inflammation-related biomarkers except for eosinophils in sinus tissue were significantly higher in patients with mould or SE (mould/SE) sensitisation (≥0.10 UA·mL−1) (n=19) than in those without (n=37) and healthy subjects (all p<0.05). Meanwhile, mould/SE sensitisation did not affect longitudinal changes in clinical outcomes after ESS. Changes in serum mould/SE-IgE levels after ESS remained unclear.ConclusionMould/SE sensitisation (≥0.10 UA·mL−1) may affect the development of Type 2 inflammation and clinical outcomes in CRS patients.

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ANALYSIS OF PNEUMONIAASSOCIATED MORTALITY OF MONKEYS IN CAPTIVITY AND THE ROLE OF METHICILLIN-SENSITIVE STAPHYLOCOCCUS AUREUS (MRSA) IN THE RECOVERED MICROFLORA SPECTRUM

Veterinary Science Today ◽

10.29326/2304-196x-2018-3-26-58-62 ◽

2018 ◽

pp. 58-62

Author(s):

V. A. Kalashnikova ◽

A. V. Demerchyan

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Bacterial Flora ◽

Autopsy Material ◽

Tissue Samples ◽

E Coli ◽

Monkey Species ◽

In Captivity ◽

Polymicrobial Communities

Pneumonia-associated mortality of different monkey species in captivity in 2017 has been analyzed. The animal death frequency and seasonality was demonstrated. Pneumonia-associated mortality in baby monkeys and old monkeys exceeds the mortality of infants and mature animals. The maximum pneumonia-mortality rate in monkeys was observed in February, April and May. The spectrum of microorganisms recovered from lungs of dead animals was identified. The prevailing bacterial flora detected in case of pneumonia was Staphylococcus aureus (43.1%) and Escherichia coli (34.9%), which were detected both in monoculture and communities. One of the peculiarities of pneumonia in monkeys is high occurrence of polymicrobial communities. Most frequently S. aureus is observed in combinations with E. coli (52.5%). All recovered S. aureus cultures were methicillin-sensitive and did not have gene mecA in their genome. During performance of bacteriological tests of autopsy material the lung tissue samples can get contaminated with the foreign flora that’s why it’s quite difficult to speak about the role of these and those microorganisms as major disease agents.

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Influence of condensation domains on activity and specificity of adenylation domains

10.1101/2021.08.23.457306 ◽

2021 ◽

Author(s):

Janik Kranz ◽

Sebastian L. Wenski ◽

Alexnder A. Dichter ◽

Helge B. Bode ◽

Kenan A. J. Bozhueyuek

Keyword(s):

Structural Features ◽

Peptide Synthetases ◽

In Situ Experiments ◽

The Subject ◽

New Perspective ◽

Condensation Domain

Many clinically used natural products are produced by non-ribosomal peptide synthetases (NRPSs), which due to their modular nature should be accessible to modification and engineering approaches. While the adenylation domain (A) plays the key role in substrate recognition and activation, the condensation domain (C) which is responsible for substrate linkage and stereochemical filtering recently became the subject of debate - with its attributed role as a "gatekeeper" being called into question. Since we have thoroughly investigated different combinations of C-A didomains in a series of in vitro, in vivo, and in situ experiments suggesting an important role to the C-A interface for the activity and specificity of the downstream A domain and not the C domain as such, we would like to contribute to this discussion. The role of the C-A interface, termed 'extended gatekeeping', due to structural features of the C domains, can also be transferred to other NRPSs by engineering, was finally investigated and characterised in an in silico approach on 30 wild-type and recombinant C-A interfaces. With these data, we not only would like to offer a new perspective on the specificity of C domains, but also to revise our previously established NRPS engineering and construction rules.

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