223 research outputs found

    Changes in the population and community structure of corals during recent disturbances (February 2016-October 2017) on Maldivian coral reefs

    Get PDF
    Climate change is the greatest threat to coral reef ecosystems. In particular, increasing ocean temperatures are causing severe and widespread coral bleaching, contributing to extensive coral loss and degradation of coral reef habitats globally. Effects of coral bleaching are not however, equally apportioned among different corals, leading to shifts in population and community structure. This study explored variation in bleaching susceptibility and mortality associated with the 2016 severe mass bleaching in the Central Maldives Archipelago. Five dominant coral taxa (tabular Acropora, Acropora humilis, Acropora muricata, Pocillopora and massive Porites) were surveyed in February 2016 and October 2017 to test for changes in abundance and size structure. Substantial taxonomic differences in rates of mortality were observed; the most severely affected taxa, Acropora, were virtually extirpated during the course of this study, whereas some other taxa (most notably, massive Porites) were relatively unaffected. However, even the least affected corals exhibited marked changes in population structure. In February 2016 (prior to recent mass-bleaching), size-frequency distributions of all coral taxa were dominated by larger size classes with over-centralized, peaked distributions (negatively skewed with positive kurtosis) reflecting a mature population structure. In October 2017, after the bleaching, coral populations were dominated by smaller and medium size classes, reflecting high levels of mortality and injury among larger coral colonies. Pronounced changes in coral populations and communities in the Maldives, caused by coral bleaching and other disturbances (outbreaks of crown-of-thorns starfish and sedimentation), will constrain recovery capacity, further compounding upon recent coral loss

    Development of a Highly Differentiated Human Primary Proximal Tubule MPS Model (aProximate MPS Flow)

    Get PDF
    \ua9 2023 by the authors.The kidney proximal tubule (PT) mediates renal drug elimination in vivo and is a major site of drug-induced toxicity. To reliably assess drug efficacy, it is crucial to construct a model in which PT functions are replicated. Current animal studies have proven poorly predictive of human outcome. To address this, we developed a physiologically relevant micro-physiological system (MPS) model of the human PT, the aProximate MPS Flow platform (Patent No: G001336.GB). In this model, primary human PT cells (hPTCs) are subjected to fluidic media flow and a shear stress of 0.01–0.2 Pa. We observe that these cells replicate the polarity of hPTCs and exhibit a higher expression of all the key transporters of SLC22A6 (OAT1), SLC22A8 (OAT3), SLC22A2 (OCT2), SLC47A1 (MATE1), SLC22A12 (URAT1), SLC2A9 (GLUT9), ABCB1 (MDR1), ABCC2 (MRP2), LRP2 (megalin), CUBN (cubilin), compared with cells grown under static conditions. Immunofluorescence microscopy confirmed an increase in OAT1, OAT3, and cilia protein expression. Increased sensitivity to nephrotoxic protein cisplatin was observed; creatinine and FITC-albumin uptake was significantly increased under fluidic shear stress conditions. Taken together, these data suggest that growing human PT cells under media flow significantly improves the phenotype and function of hPTC monolayers and has benefits to the utility and near-physiology of the model

    Variation in growth rates of branching corals along Australia's Great Barrier Reef

    Get PDF
    Coral growth is an important component of reef health and resilience. However, few studies have investigated temporal and/or spatial variation in growth of branching corals, which are important contributors to the structure and function of reef habitats. This study assessed growth (linear extension, density, and calcification) of three branching coral species (Acropora muricata, Pocillopora damicornis and Isopora palifera) at three distinct locations (Lizard Island, Davies/Trunk Reef, and Heron Island) along Australia’s Great Barrier Reef (GBR). Annual growth rates of all species were highest at Lizard Island and declined with increasing latitude, corresponding with differences in temperature. Within locations, however, seasonal variation in growth did not directly correlate with temperature. Between October 2012 and October 2014, the highest growth of A. muricata was in the 2013–14 summer at Lizard Island, which was unusually cool and ~0.5 °C less than the long-term summer average temperature. At locations where temperatures reached or exceeded the long-term summer maxima, coral growth during summer periods was equal to, if not lower than, winter periods. This study shows that temperature has a significant influence on spatiotemporal patterns of branching coral growth, and high summer temperatures in the northern GBR may already be constraining coral growth and reef resilience

    Materials analysis and image-based modelling of transmissibility and strain behaviour in approved face mask microstructures

    Get PDF
    Data availability: The datasets generated and/or analysed during the current study are available from the corresponding author on reasonable request.Copyright © The Author(s) 2022. Comparisons are made between six different approved face masks concerning their particle transmissibility allied to mechanical properties. The latter involves material testing and stretch or strain behaviour under load. SEM and X-ray elemental analyses showed contrasting structures between random and ordered fibre orientations. These constitute the mask designs where transmissibility is to be minimised. Airflow velocity measurement enabled filtration to be measured between the different mask designs, from two to six layers of different fabrics in combination. SEM provided the fibre diameter and pore size of each mask layer, up to a maximum of six. Stretching each complete mask showed its elasticity and recovery behaviour on an energy basis. The energy conversion involved in mask straining involves areas enclosed within steady and cyclic load-extension plots. Thus, the work done in extending a mask and the energy recovered from its release identified a hysteresis associated with an irrecoverable permanent stretch to the mask fabric. Failure of individual layers, which occurred successively in extended stretch tests, appeared as a drop in a load-extension response. That change is associated with permanent damage to each mask and friction contact within the rearrangement of loose fibre weaves. Masks with the greatest number of layers reduced particle transmissibility. However, woven or ordered mask fabrics in two layers with different orientations provided comparable performance. Simulation of each mechanical response, velocity streamlining and fibre distribution within the mask layers are also presented.Design Department at Brunel University London

    Value of a Multidisciplinary Approach in Sinonasal Inverted Papilloma with Extensive Ossification

    Get PDF
    Objective: Background: Casa Report: Conclusions: Rare disease Inverted papilloma is a benign epithelial lesion of the nasal cavities. Although commonly encountered in clinical practice, it rarely presents with extensive ossification and few cases have been described in the literature. Herein, we describe the case of a 51-year-old man who presented to clinical attention for persistent right nasal obstruction. Magnetic resonance imaging (MRI) and computed tomography (CT) scans of the facial bones showed a lobated lesion with ossification occupying most of the right nasal cavity. The lesion was removed by endoscopic sinus surgery, leaving the surrounding bone structures intact. On pathological examination, mature bone tissue was found within an inverted papilloma. The pathologist contacted the surgeon, who confirmed that no healthy bone tissue was removed during the procedure. Therefore, a diagnosis of inverted papilloma with ossification could be made without the use of ancillary techniques. Inverted papilloma with ossification is a common lesion with a rare feature. Our report investigates the diagnostic difficulties of a paradigmatic case, highlighting the importance of multidisciplinary teamwork in reach-ing the final diagnosis

    Ultrasound-assessed lung aeration correlates with respiratory system compliance in adults and neonates with acute hypoxemic restrictive respiratory failure: an observational prospective study

    Get PDF
    Background: Lung ultrasound allows lung aeration to be assessed through dedicated lung ultrasound scores (LUS). Despite LUS have been validated using several techniques, scanty data exist about the relationships between LUS and compliance of the respiratory system (Crs) in restrictive respiratory failure. Aim of this study was to investigate the relationship between LUS and Crs in neonates and adults affected by acute hypoxemic restrictive respiratory failure, as well as the effect of patients' age on this relationship. Methods: Observational, cross-sectional, international, patho-physiology, bi-center study recruiting invasively ventilated, adults and neonates with acute respiratory distress syndrome (ARDS), neonatal ARDS (NARDS) or respiratory distress syndrome (RDS) due to primary surfactant deficiency. Subjects without lung disease (NLD) and ventilated for extra-pulmonary conditions were recruited as controls. LUS, Crs and resistances (Rrs) of the respiratory system were measured within 1 h from each other. Results: Forty adults and fifty-six neonates were recruited. LUS was higher in ARDS, NARDS and RDS and lower in control subjects (overall p < 0.001), while Crs was lower in ARDS, NARDS and RDS and higher in control subjects (overall p < 0.001), without differences between adults and neonates. LUS and Crs were correlated in adults [r = - 0.86 (95% CI - 0.93; - 0.76), p < 0.001] and neonates [r = - 0.76 (95% CI - 0.85; - 0.62), p < 0.001]. Correlations remained significant among subgroups with different causes of respiratory failure; LUS and Rrs were not correlated. Multivariate analyses confirmed the association between LUS and Crs both in adults [B = - 2.8 (95% CI - 4.9; - 0.6), p = 0.012] and neonates [B = - 0.045 (95% CI - 0.07; - 0.02), p = 0.001]. Conclusions: Lung aeration and compliance of the respiratory system are significantly and inversely correlated irrespective of patients' age. A restrictive respiratory failure has the same ultrasound appearance and mechanical characteristics in adults and neonates

    po 320 gene panel mutation screening for a better molecular stratification of colorectal cancer patients

    Get PDF
    Introduction Colorectal carcinoma (CRC) is one of the most commonly diagnosed cancers worldwide. The metastatic disease contributes to the high mortality rate reported for such tumours. Significant benefit on overall survival was brought about the introduction of monoclonal antibodies anti-EGFR and anti-VEGF used in combination with chemotherapy in metastatic CRC (mCRC). While anti-VEGF treatment does not require biomarker-based selection criteria, the potential efficacy of anti-EGFR antibodies is neglected to patients with activating mutations in KRAS and NRAS (RAS) genes, whose molecular analysis became a clinical routine. The advent of Next Generation Sequencing (NGS) instruments, able to reach quick testing of multiple clinically-relevant hotspots, yet maintaining precision and low costs, allows the simultaneous determination of the mutation status of an expanding number of genes. Despite only few of these molecular biomarkers have gained clinical utility in the routine oncological practice, the acquisition of more complex cancer mutational patterns may provide more efficient tumour characterisation for prognostic and predictive purposes and highlight actionable targets. Material and methods We sequenced 639 mCRC samples by IT-PGM platform using a panel of hotspots and targeted regions of 22 genes (including RAS) commonly involved in CRCs. MSI analyses on 89 patients have been performed with a single fluorescent system comprising BAT25 and BAT26 mononucleotide repeats. Results and discussions We identified recurrent mutations (≥1%) in 12/22 genes, being KRAS, TP53 and PIK3CA the most frequently mutated ones. Statistical analysis, indicated that the mutation associations follow a non-random distribution. Categorization of the cases on the base of KRAS and p53 mutation status led us the definition of 8 Mutation Association Patterns (MAPs) characterised by specific mutation associations. Analysis of the clinicopathological data available for 89 out of 639 cases indicates interesting trends for the associations of MAPs with specific parameters, some of which reached statistical significance. Conclusion Application of NGS gene panel as a routine for the characterisation of RAS/BRAF status required for predictive purposes in CRC patients, may provide additional prognostic/predictive information, with no significant extra-costs
    • …
    corecore