Microscale tracking of coral-vibrio interactions

AbstractTo improve our understanding of coral infection and disease, it is important to study host-pathogen interactions at relevant spatio-temporal scales. Here, we provide a dynamic microscopic view of the interaction between a coral pathogen, Vibrio coralliilyticus and its coral host Pocillopora damicornis. This was achieved using a microfluidics-based system facilitating control over flow, light and temperature conditions. Combined with time-resolved biochemical and microbial analyses of the system exudates, this approach provides novel insights into the early phases of a coral infection at unprecedented spatio-temporal resolution. We provide evidence that infection may occur through ingestion of the pathogen by the coral polyps, or following pathogen colonization of small tissue lesions on the coral surface. Pathogen ingestion invariably induced the release of pathogen-laden mucus from the gastrovascular cavity. Despite the high bacterial load used in our experiments, approximately one-third of coral fragments tested did not develop further symptoms. In the remaining two-thirds, mucus spewing was followed by the severing of calicoblastic connective tissues (coenosarc) and subsequently necrosis of most polyps. Despite extensive damage to symptomatic colonies, we frequently observed survival of individual polyps, often accompanied by polyp bail-out. Biochemical and microbial analyses of exudates over the course of symptomatic infections revealed that severing of the coenosarc was followed by an increase in matrix metaloprotease activity, and subsequent increase in both pathogen and total bacterial counts. Combined, these observations provide a detailed description of a coral infection, bringing us a step closer to elucidating the complex interactions underlying coral disease.

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Microscale tracking of coral disease reveals timeline of infection and heterogeneity of polyp fate

10.1101/302778 ◽

2018 ◽

Cited By ~ 5

Author(s):

Assaf R. Gavish ◽

Orr H. Shapiro ◽

Esti Kramarsky-Winter ◽

Assaf Vardi

Keyword(s):

Disease Progression ◽

Defense Mechanism ◽

Coral Disease ◽

Coral Host ◽

Pocillopora Damicornis ◽

Spatial And Temporal Scales ◽

Infection Dynamics ◽

Key Steps ◽

Coral Pathogen ◽

Gastrovascular System

AbstractCoral disease is often studied at scales ranging from single colonies to the entire reef. This is particularly true for studies following disease progression through time. To gain a mechanistic understanding of key steps underlying infection dynamics, it is necessary to study disease progression, and host-pathogen interactions, at relevant microbial scales. Here we provide a dynamic view of the interaction between the model coral pathogen Vibrio coralliilyticus and its coral host Pocillopora damicornis at unprecedented spatial and temporal scales. This view is achieved using a novel microfluidics-based system specifically designed to allow microscopic study of coral infection in-vivo under controlled environmental conditions. Analysis of exudates continuously collected at the system’s outflow, allows a detailed biochemical and microbial analyses coupled to the microscopic observations of the disease progression. The resulting multilayered dataset provides the most detailed description of a coral infection to-date, revealing distinct pathogenic processes as well as the defensive behavior of the coral host. We provide evidence that infection in this system occurs following ingestion of the pathogen, and may then progress through the gastrovascular system. We further show infection may spread when pathogens colonize lesions in the host tissue. Copious spewing of pathogen-laden mucus from the polyp mouths results in effective expulsion of the pathogen from the gastrovascular system, possibly serving as a first line of defense. A secondary defense mechanism entails the severing of calicoblastic connective tissues resulting in the controlled isolation of diseased polyps, or the survival of individual polyps within infected colonies. Further investigations of coral-pathogen interactions at these scales will help to elucidate the complex interactions underlying coral disease, as we as the versatile adaptive response of the coral ecosystems to fluctuating environments.

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A data reduction and compression description for high throughput time-resolved electron microscopy

Nature Communications ◽

10.1038/s41467-020-20694-z ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Abhik Datta ◽

Kian Fong Ng ◽

Deepan Balakrishnan ◽

Melissa Ding ◽

See Wee Chee ◽

...

Keyword(s):

Electron Microscopy ◽

Temporal Resolution ◽

Data Reduction ◽

Accurate Estimation ◽

Data Streaming ◽

Compression Scheme ◽

Raw Data ◽

Time Resolved ◽

Detection And Counting ◽

Spatio Temporal

AbstractFast, direct electron detectors have significantly improved the spatio-temporal resolution of electron microscopy movies. Preserving both spatial and temporal resolution in extended observations, however, requires storing prohibitively large amounts of data. Here, we describe an efficient and flexible data reduction and compression scheme (ReCoDe) that retains both spatial and temporal resolution by preserving individual electron events. Running ReCoDe on a workstation we demonstrate on-the-fly reduction and compression of raw data streaming off a detector at 3 GB/s, for hours of uninterrupted data collection. The output was 100-fold smaller than the raw data and saved directly onto network-attached storage drives over a 10 GbE connection. We discuss calibration techniques that support electron detection and counting (e.g., estimate electron backscattering rates, false positive rates, and data compressibility), and novel data analysis methods enabled by ReCoDe (e.g., recalibration of data post acquisition, and accurate estimation of coincidence loss).

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Lung Microbiome Differentially Impacts Survival of Patients with Non-Small Cell Lung Cancer Depending on Tumor Stroma Phenotype

Biomedicines ◽

10.3390/biomedicines8090349 ◽

2020 ◽

Vol 8 (9) ◽

pp. 349 ◽

Cited By ~ 1

Author(s):

Olga Kovaleva ◽

Polina Podlesnaya ◽

Madina Rashidova ◽

Daria Samoilova ◽

Anatoly Petrenko ◽

...

Keyword(s):

Lung Cancer ◽

Normal Tissue ◽

Bacterial Load ◽

Alpha Diversity ◽

Tumor Stroma ◽

Small Cell ◽

Adjacent Normal Tissue ◽

Small Cell Lung ◽

Lung Microbiome ◽

High Bacterial Load

The link between a lung tumor and the lung microbiome is a largely unexplored issue. To investigate the relationship between a lung microbiome and the phenotype of an inflammatory stromal infiltrate, we studied a cohort of 89 patients with non-small cell lung cancer. The microbiome was analyzed in tumor and adjacent normal tissue by 16S rRNA amplicon sequencing. Characterization of the tumor stroma was done using immunohistochemistry. We demonstrated that the bacterial load was higher in adjacent normal tissue than in a tumor (p = 0.0325) with similar patterns of taxonomic structure and alpha diversity. Lung adenocarcinomas did not differ in their alpha diversity from squamous cell carcinomas, although the content of Gram-positive bacteria increased significantly in the adenocarcinoma group (p = 0.0419). An analysis of an inflammatory infiltrate of tumor stroma showed a correlation of CD68, iNOS and FOXP3 with a histological type of tumor. For the first time we showed that high bacterial load in the tumor combined with increased iNOS expression is a favorable prognostic factor (HR = 0.1824; p = 0.0123), while high bacterial load combined with the increased number of FOXP3+ cells is a marker of poor prognosis (HR = 4.651; p = 0.0116). Thus, we established that bacterial load of the tumor has an opposite prognostic value depending on the status of local antitumor immunity.

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High bacterial load in negative pressure wound therapy (NPWT) foams used in the treatment of chronic wounds

Wound Repair and Regeneration ◽

10.1111/wrr.12088 ◽

2013 ◽

Vol 21 (5) ◽

pp. 677-681 ◽

Cited By ~ 27

Author(s):

Erlangga Yusuf ◽

Xavier Jordan ◽

Martin Clauss ◽

Olivier Borens ◽

Mark Mäder ◽

...

Keyword(s):

Negative Pressure ◽

Negative Pressure Wound Therapy ◽

Chronic Wounds ◽

Bacterial Load ◽

Wound Therapy ◽

High Bacterial Load

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Pneumococcal pneumonia and invasive pneumococcal disease: immunopathogenesis and diagnosis

Pneumologia ◽

10.2478/pneum-2019-0009 ◽

2019 ◽

Vol 68 (1) ◽

pp. 8-14

Author(s):

Gina Amanda ◽

Dianiati Kusumo Sutoyo ◽

Erlina Burhan

Keyword(s):

Immune System ◽

Invasive Pneumococcal Disease ◽

Pneumococcal Disease ◽

Pneumococcal Pneumonia ◽

Bacterial Load ◽

Adaptive Immune System ◽

Signs And Symptoms ◽

Community Acquired Pneumonia ◽

High Bacterial Load ◽

Droplet Nuclei

Abstract Streptococcus pneumoniae is the most common aetiology of community-acquired pneumonia (CAP). It has many virulence factors, the most important being a polysaccharide capsule (Cps). There are 97 different serotypes of pneumococcal based on Cps which include both colonization and invasive serotypes. Pneumococcal pneumonia may exist as a result of either aspiration of bacteria in the nasopharynx or inhalation of droplet nuclei which contains bacteria until they reach the lower respiratory tract. This condition will activate both innate and adaptive immune system. The diagnosis of pneumococcal pneumonia is established in a patient who has the signs and symptoms of pneumonia, accompanied by the detection of S. pneumoniae in microbiology examination. Pneumococcus may also penetrate into a normally sterile site such as bloodstream, meninges, and pleural cavity, and infection of pneumococcus in those sites are defined as an invasive pneumococcal disease (IPD). High bacterial load, dysfunction of the immune system, and co-colonization of another microorganism may also lead to IPD.

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Organized Framework of Main Possible Applications of Sheep Wool Fibers in Building Components

Sustainability ◽

10.3390/su12030761 ◽

2020 ◽

Vol 12 (3) ◽

pp. 761 ◽

Cited By ~ 1

Author(s):

Monica C.M. Parlato ◽

Simona M.C. Porto

Keyword(s):

Bacterial Load ◽

Natural Fibers ◽

Green Building ◽

Production Costs ◽

Acoustic Properties ◽

Wool Fibers ◽

Rural Buildings ◽

Building Components ◽

High Bacterial Load ◽

Sheep Wool

Greasy sheep wool is currently considered a special waste for its high bacterial load, with expensive disposal costs for sheep breeders. For this reason, wool is often burned or buried, with serious consequences for the environment. On the other hand, sheep wool is well regarded as one of the most performative insulating natural fibers due to its thermo-hygrometric and acoustic properties. In the building sector, sheep wool meets the requirements of green building components because it is an eco-friendly material, there is a surplus of it, it is annually renewable, and totally recyclable. If used instead of common insulation materials (e.g., fiberglass, rock wool, polyurethane foam, polystyrene), sheep wool offers significant benefits for sustainability such as a reduction in the production costs for new insulating materials and in environmental pollution. Mechanical and physical properties of sheep wool investigated in previous studies were assessed and discussed with the aim of providing an organized framework of possible applications of wool fibers in building components. This paper highlights in detail aspects that have not yet been investigated enough to detect new potential uses of sheep wool fibers in rural buildings and the reuse of traditional ones.

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Spatio-Temporal Development of Supercavitation Over an Impulsively Launched Projectile

Volume 2: Fora ◽

10.1115/fedsm2006-98115 ◽

2006 ◽

Author(s):

C. J. Weiland ◽

P. P. Vlachos

Keyword(s):

High Speed ◽

Temporal Development ◽

Two Phase ◽

Time Resolved ◽

Gas Gun ◽

Supercavitating Flow ◽

Image Velocimetry ◽

Spatio Temporal ◽

Asymmetric Vortices ◽

First Time

Supercavitation inception and formation was studied over blunt projectiles. The projectiles were fired using a gas gun method. In this method, projectiles are launched under the action of expanding detonation gases. Both qualitative and quantitative optical flow diagnostics using high speed digital imaging were used to analyze the spatio-temporal development of the supercavitating flow. For the first time, quantification of the supercavitation was achieved using Time Resolved Digital Particle Image Velocimetry (TRDPIV) detailing the two phase flow field surrounding the translating projectiles and the gas vapor bubble. Experimental results indicate that the supercavity forms at the aft end of the projectile and travels forward along the direction of projectile travel. The impulsive start of the projectile generates two asymmetric vortices which are shed from the blunt nose of the projectile. The vortices interact with the moving cavity and subsequently deform. This interaction is believed to directly contribute to the instabilities in the flight path.

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Factors influencing phagocytosis of Salmonella typhimurium by macrophages in murine schistosomiasis

Revista da Sociedade Brasileira de Medicina Tropical ◽

10.1590/s0037-86821997000200003 ◽

1997 ◽

Vol 30 (2) ◽

pp. 101-106 ◽

Cited By ~ 4

Author(s):

Maria Imaculada Muniz-Junqueira ◽

Aluízio Prata ◽

Carlos Eduardo Tosta

Keyword(s):

Salmonella Typhimurium ◽

Schistosoma Mansoni ◽

Bacterial Load ◽

Concurrent Infection ◽

Functional Limit ◽

Phagocytic Capacity ◽

Specific Antibodies ◽

Factors Influencing ◽

High Bacterial Load ◽

Number Of Bacteria

We investigated the influence of Salmonella typhimurium load and specific antibodies on phagocytosis in schistosomiasis. Macrophages from Schistosoma mansoni-infected mice showed depressed capacity to increase the phagocytosis in the presence of a high bacterial load, due to a reduced involvement of these cells in phagocytosis and to a deficient ability to increase the number of phagocytosed bacteria. Normal and Salmonella-infected mice increased their phagocytic capacity when exposed to a high bacterial load. Antibody to Salmonella increased the phagocytic capacity of macrophages from Schistosoma-infected mice due to an increase in the number of bacteria phagocytosed but caused no modification in the number of macrophages engaged in phagocytosis. Our data indicate that macrophages from Schistosoma-infected mice work close to their functional limit, since no increase in phagocytosis was observed after increasing the bacterial load. Specific antibodies can improve their phagocytic capacity and, therefore, could help clearing concurrent infection.

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A Complex Interplay of Anionic Phospholipid Binding Regulates 3′-Phosphoinositide-Dependent-Kinase-1 Homodimer Activation

Scientific Reports ◽

10.1038/s41598-019-50742-8 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Gloria de las Heras-Martínez ◽

Véronique Calleja ◽

Remy Bailly ◽

Jean Dessolin ◽

Banafshé Larijani ◽

...

Keyword(s):

Conformational Dynamics ◽

Pi3k Pathway ◽

Correlation Spectroscopy ◽

Fluorescence Lifetime Imaging ◽

Anionic Phospholipid ◽

Direct Role ◽

Time Resolved ◽

Anionic Phospholipids ◽

Spatio Temporal ◽

Phosphoinositide Dependent Kinase

Abstract 3′-Phosphoinositide-dependent-Kinase-1 (PDK1) is a master regulator whereby its PI3-kinase-dependent dysregulation in human pathologies is well documented. Understanding the direct role for PtdIns(3,4,5)P3 and other anionic phospholipids in the regulation of PDK1 conformational dynamics and its downstream activation remains incomplete. Using advanced quantitative-time-resolved imaging (Fluorescence Lifetime Imaging and Fluorescence Correlation Spectroscopy) and molecular modelling, we show an interplay of antagonistic binding effects of PtdIns(3,4,5)P3 and other anionic phospholipids, regulating activated PDK1 homodimers. We demonstrate that phosphatidylserine maintains PDK1 in an inactive conformation. The dysregulation of the PI3K pathway affects the spatio-temporal and conformational dynamics of PDK1 and the activation of its downstream substrates. We have established a new anionic-phospholipid-dependent model for PDK1 regulation, depicting the conformational dynamics of multiple homodimer states. We show that the dysregulation of the PI3K pathway perturbs equilibrium between the PDK1 homodimer conformations. Our findings provide a role for the PtdSer binding site and its previously unrewarding role in PDK1 downregulation, suggesting a possible therapeutic strategy where the constitutively active dimer conformer of PDK1 may be rendered inactive by small molecules that drive it to its PtdSer-bound conformer.

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