Investigating Inflammasome Activation in Response to Legionella Pneumophila and its Application to Other Bacterial Pathogens

The mucosal surfaces of metazoan organisms provide niches for colonization by commensal microbes. However, these barrier surfaces also encounter pathogens. Therefore, sentinel immune cells must be capable of distinguishing between pathogenic and non-pathogenic organisms to tailor appropriate immune responses. Virulent microorganisms often uniquely possess mechanisms for accessing the host cell cytosol. Therefore, to detect pathogens, innate immune cells encode cytosolic receptors, which recognize conserved, pathogen-associated molecular patterns. Many mammalian cytosolic receptors activate the inflammasome, a multi-protein complex that activates the host enzyme caspase-1. Caspase-1 mediates IL-1 family cytokine release and a pro-inflammatory form of cell death, which are important for host defense. The canonical inflammasome activates caspase-1, but recent studies have shown that a related enzyme, caspase-11, contributes to inflammasome activation. However, it remains unclear if caspase-11 mediates inflammasome responses against bacteria that use virulence-associated secretion systems to deliver bacterial products into the host cytosol. Additionally, humans encode two orthologs of caspase-11, caspase-4 and caspase-5, and it is unclear if either enzyme contributes to inflammasome activation in primary macrophages. Furthermore, the bacterial ligands that trigger inflammasome activation in human cells are poorly defined. Legionella pneumophila, which causes pneumonia, uses a specialized secretion system to access the host cytosol to establish a replicative niche in both murine and human cells. Therefore, we investigated the host and bacterial requirements for inflammasome activation in response to L. pneumophila, and we interrogated if these requirements are conserved for the response against other Gram-negative bacterial pathogens. Our studies demonstrate that caspase-11 contributes to IL-1 release and cell death in response to bacterial pathogens in murine macrophages, and we find that inflammasome activation requires the presence of virulence-associated secretion systems. Using neutralizing antibodies, we show that IL-1α and IL-1β have distinct roles in pulmonary defense against L. pneumophila in vivo. Through siRNA knockdown studies, we demonstrate that human caspase-4 has a conserved role in inflammasome activation in response to multiple Gram-negative bacterial pathogens. Finally, using bacterial mutants, we show that flagellin is a trigger for inflammasome activation in human macrophages. Overall, our studies help define the mechanism by which host cells initiate defense against bacterial pathogens

Human activity recognition from inertial sensor time-series using batch normalized deep LSTM recurrent networks

In recent years machine learning methods for human activity recognition have been found very effective. These classify discriminative features generated from raw input sequences acquired from body-worn inertial sensors. However, it involves an explicit feature extraction stage from the raw data, and although human movements are encoded in a sequence of successive samples in time most state-of-the-art machine learning methods do not exploit the temporal correlations between input data samples. In this paper we present a Long-Short Term Memory (LSTM) deep recurrent neural network for the classification of six daily life activities from accelerometer and gyroscope data. Results show that our LSTM can processes featureless raw input signals, and achieves 92 % average accuracy in a multi-class-scenario. Further, we show that this accuracy can be achieved with almost four times fewer training epochs by using a batch normalization approach

Kleinian groups and the complex of curves

We examine the internal geometry of a Kleinian surface group and its relations to the asymptotic geometry of its ends, using the combinatorial structure of the complex of curves on the surface. Our main results give necessary conditions for the Kleinian group to have `bounded geometry' (lower bounds on injectivity radius) in terms of a sequence of coefficients (subsurface projections) computed using the ending invariants of the group and the complex of curves. These results are directly analogous to those obtained in the case of punctured-torus surface groups. In that setting the ending invariants are points in the closed unit disk and the coefficients are closely related to classical continued-fraction coefficients. The estimates obtained play an essential role in the solution of Thurston's ending lamination conjecture in that case.Comment: 32 pages. Published copy, also available at http://www.maths.warwick.ac.uk/gt/GTVol4/paper3.abs.htm

HY5 is not integral to light mediated stomatal development in Arabidopsis

Light is a crucial signal that regulates many aspects of plant physiology and growth including the development of stomata, the pores in the epidermal surface of the leaf. Light signals positively regulate stomatal development leading to changes in stomatal density and stomatal index (SI; the proportion of cells in the epidermis that are stomata). Both phytochrome and cryptochrome photoreceptors are required to regulate stomatal development in response to light. The transcription factor ELONGATED HYPOCOTYL 5 (HY5) is a key regulator of light signalling, acting downstream of photoreceptors. We hypothesised that HY5 could regulate stomatal development in response to light signals due to the putative presence of HY5 binding sites in the promoter of the STOMAGEN (STOM) gene, which encodes a peptide regulator of stomatal development. Our analysis shows that HY5 does have the potential to regulate the STOM promoter in vitro and that HY5 is expressed in both the epidermis and mesophyll. However, analysis of hy5 and hy5 hyh double mutants (HYH; HY5-HOMOLOG), found that they had normal stomatal development under different light conditions and the expression of stomatal developmental genes was not perturbed following light shift experiments. Analysis of stable lines overexpressing HY5 also showed no change in stomatal development or the expression of stomatal developmental genes. We therefore conclude that whilst HY5 has the potential to regulate the expression of STOM, it does not have a major role in regulating stomatal development in response to light signals

Nexus researching church toddler groups

The Headlines This unique research project revealed fascinating insights into the spiritual flourishing of very young children and how this is nourished within church toddler groups in England. The findings have uncovered evidence of very young children exploring self-understanding and the nurturing of relationships with others. We found that church toddler groups contribute to children’s spiritual flourishing through: • Providing an environment that fosters a non-threatening connection with spirituality and faith. • Nurturing and sustaining relationships with families. • Offering a safe place for young families to come together, play together, and feel supported in their spiritual well-being. • Enabling a sense of belonging to the church community through engagement in the church toddler group. However, we also found that: • There is a need for adults to have a deeper awareness of the significant role they play in enabling the spiritual flourishing of very young children. • A common misunderstanding of spiritual nurture in terms of faith development hampers focused attention on the spiritual nurture of very young children

Severe pneumonia due to Parachlamydia acanthamoebae following intranasal inoculation: a mice model.

Parachlamydia acanthamoebae is an obligate intracellular bacterium naturally infecting free-living amoebae. The role of this bacterium as an agent of pneumonia is suggested by sero-epidemiological studies and molecular surveys. Furthermore, P. acanthamoebae may escape macrophages microbicidal effectors. Recently, we demonstrated that intratracheal inoculation of P. acanthamoebae induced pneumonia in 100% of infected mice. However, the intratracheal route of infection is not the natural way of infection and we therefore developed an intranasal murine model. Mice inoculated with P. acanthamoebae by intranasal inoculation lost 18% of their weight up to 8 days post-inoculation. All mice presented histological signs of pneumonia at day 2, 4, 7, and 10 post-inoculation, whereas no control mice harboured signs of pneumonia. A 5-fold increase in bacterial load was observed from day 0 to day 4 post-inoculation. Lungs of inoculated mice were positive by Parachlamydia-specific immunohistochemistry 4 days post-inoculation, and P. acanthamoebae were localized within macrophages. Thus, we demonstrated that P. acanthamoebae induce a severe pneumonia in mice. This animal model (i) further supports the role of P. acanthamoebae as an agent of pneumonia, confirming the third Koch postulate, and (ii) identified alveolar macrophages as one of the initial cells where P. acanthamoebae is localized following infection

Linking dominant rainfall-runoff event hydrologic response dynamics with nitrate and chloride load estimates of three boreal Shield catchments

Understanding hydrological dynamics in boreal Shield catchments is critical for projecting changes in stream runoff and chemistry in a region that is sensitive to climate change. Previous work has mostly focused on a limited number of events over one or a few seasons because of the relative scarcity of high-frequency datasets and automated tools for rainfall-runoff event delineation. For the boreal region, a greater understanding of seasonality in hydrologic response and solute export related to rainfall-initiated events is needed, as significant shifts in hydrologic regime from climate change are expected. This study aimed to help resolve these knowledge gaps by assessing event-scale hydrologic response dynamics and stream loads of nitrate and chloride using long-term data from three boreal Shield catchments. Hydrometric and stream chemistry data from 2001-2018 were analyzed to delineate rainfall-runoff events and estimate event nitrate and chloride loads. Event hydrologic response and loads were highly variable, especially with respect to catchment runoff initiation. Only subtle differences in hydrologic response dynamics were observed between summer and fall events, while seasonal differences in event nitrate and chloride loads were mostly statistically significant. Interestingly, a wide range of rainfall-runoff events classified by response magnitude and timing were associated with differences in nitrate and chloride export. This study further confirms the utility of long-term high-frequency datasets and illustrates the need for additional work to further assess long-term changes in event-based hydrologic response and stream solute concentrations in the boreal region."This work was funded by an NSERC Discovery Grant to NJC."https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020JG00618

The reflectance of human skin in the millimeter-wave band

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. The millimeter-wave band is an ideal part of the electromagnetic radiation to diagnose human skin conditions because this radiation interacts only with tissue down to a depth of a millimetre or less over the band range from 30 GHz to 300 GHz. In this paper, radiometry is used as a non-contact sensor for measuring the human skin reflectance under normal and wet skin conditions. The mean reflectance of the skin of a sample of 50 healthy participants over the (80–100) GHz band was found to be ~0.615 with a standard deviation of ~0.088, and an experimental measurement uncertainty of ±0.005. The thinner skin regions of the back of the hand, the volar forearms and the inner wrist had reflectances 0.068, 0.068 and 0.062 higher than the thicker skin regions of the palm of the hand, the dorsal forearm and the outer wrist skin. Experimental measurements of human skin reflectance in a normal and a wet state on the back of the hand and the palm of the hand regions indicated that the mean differences in the reflectance before and after the application of water were ~0.078 and ~0.152, respectively. These differences were found to be statistically significant as assessed using t-tests (34 paired t-tests and six independent t-tests were performed to assess the significance level of the mean differences in the reflectance of the skin). Radiometric measurements in this paper show the quantitative variations in the skin reflectance between locations, sexes, and individuals. The study reveals that these variations are related to the skin thickness and water content, a capability that has the potential to allow radiometry to be used as a non-contact sensor to detect and monitor skin conditions such as eczema, psoriasis, malignancy, and burn wounds

The AgED Study. Age-related eye disease (AgED) in South Australian general practice: are we blind to early detection and intervention?

Published online 2 August 2016The AgED Study aimed to evaluate the detection, awareness and management of age-related eye disease (AgED) in South Australian general practice. Three South Australian metropolitan general practices were recruited and all patients aged 75 years and older were invited to participate. A cross-sectional postal questionnaire and retrospective audit of consenting patients' medical records was performed. On average, patients had their last eye check 9 months ago; the majority (64.9%) performed by an optometrist. Only 7.6% had visited their GP for their last eye check, mostly (90.5%) for a mandatory 'Fitness to Drive' medical assessment. There were marked differences in GP recording v. self-reported AgED and a marked discrepancy in the prevalence rates of AgED, visual impairment and blindness in this study compared with Australian population-based prevalence surveys. Despite the lack of GP documentation of eye disease, the majority of patients engaged in timely eye checks with either an optometrist or ophthalmologist, and their overall visual function and vision-related quality of life (QoL) were satisfactory.Chelsea Guymer, Robert Casson, Cate Howell and Nigel Stock

Disinfection of Ebola Virus in Sterilized Municipal Wastewater

Concerns have been raised regarding handling of Ebola virus contaminated wastewater, as well as the adequacy of proposed disinfection approaches. In the current study, we investigate the inactivation of Ebola virus in sterilized domestic wastewater utilizing sodium hypochlorite addition and pH adjustment. No viral inactivation was observed in the one-hour tests without sodium hypochlorite addition or pH adjustment. No virus was recovered after 20 seconds (i.e. 4.2 log10 unit inactivation to detection limit) following the addition of 5 and 10 mg L-1 sodium hypochlorite, which resulted in immediate free chlorine residuals of 0.52 and 1.11 mg L-1, respectively. The addition of 1 mg L-1 sodium hypochlorite resulted in an immediate free chlorine residual of 0.16 mg L-1, which inactivated 3.5 log10 units of Ebola virus in 20 seconds. Further inactivation was not evident due to the rapid consumption of the chlorine residual. Elevating the pH to 11.2 was found to significantly increase viral decay over ambient conditions. These results indicate the high susceptibility of the enveloped Ebola virus to disinfection in the presence of free chlorine in municipal wastewater; however, we caution that extension to more complex matrices (e.g. bodily fluids) will require additional verification