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Abstract Background Heart diseases, particularly heart failure, significantly impact patient quality of life and mortality rates. Functional capacity assessment is vital for predicting prognosis and risk in these patients. While the cardiopulmonary exercise test is considered the gold standard, the 6-minute walk test has emerged as a more accessible alternative. However, the screening accuracy and optimal cut-off points of the 6-minute walk test for detecting severely reduced functional capacity in cardiac pathologies, including heart failure with preserved ejection fraction, are unclear. The study aimed to analyse the diagnostic accuracy of the 6-minute walk test for detecting reduced functional capacity, defined as VO2max

Abstract Marine Porifera host diverse microbial communities, which influence host metabolism and fitness. However, functional relationships between sponge microbiomes and metabolic signatures are poorly understood. We integrate microbiome characterization, metabolomics and microbial predicted functions of four coexisting Mediterranean sponges –Petrosia ficiformis, Chondrosia reniformis, Crambe crambe and Chondrilla nucula. Microscopy observations reveal anatomical differences in microbial densities. Microbiomes exhibit strong species-specific trends. C. crambe shares many rare amplicon sequence variants (ASV) with the surrounding seawater. This suggests important inputs of microbial diversity acquired by selective horizontal acquisition. Phylum Cyanobacteria is mainly represented in C. nucula and C. crambe. According to putative functions, the microbiome of P. ficiformis and C. reniformis are functionally heterotrophic, while C. crambe and C. nucula are autotrophic. The four species display distinct metabolic profiles at single compound level. However, at molecular class level they share a “core metabolome”. Concurrently, we find global microbiome-metabolome association when considering all four sponge species. Within each species still, sets of microbe/metabolites are identified driving multi-omics congruence. Our findings suggest that diverse microbial players and metabolic profiles may promote niche diversification, but also, analogous phenotypic patterns of “symbiont evolutionary convergence” in sponge assemblages where holobionts co-exist in the same area.

Background & Aims: Effective treatments for acute-on-chronic liver failure (ACLF) are a major unmet need. This proof-of-concept pilot study was aimed at evaluating the effects of plasma exchange (PE) with albumin 5% (PE-A5%) on albumin functional capacity and organ dysfunction in patients with ACLF. Methods: Ten adult patients were enrolled in a single-center phase II, prospective, open-label, non-controlled study. Six PE-A5% sessions were performed in 10 days followed by a 1-month follow-up visit. Albumin functional capacity and circulatory function were assessed, as were renal, cerebral, and liver function, and systemic inflammation. The main safety variable was the percentage of PE sessions associated with at least one procedure-related adverse event (AE). Results: Patients with ACLF showed lower albumin binding capacity, lower antioxidant capacity, and lower levels of albumin with preserved structure compared to healthy donors (n = 19). From baseline to day 11, PE-A5% treatment increased albumin levels and improved albumin binding capacity to Sudlow site II (15.3±1.6 mg/ml to 18.9±1.7 mg/ml; p = 0.003), fatty acid-binding capacity (8.2±1.4 μM to 3.1±1.5 μM; p = 0.013) and antioxidant capacity (human mercaptalbumin 9.5±1.5 mg/ml to 14.6±1.6 mg/ml; p = 0.001). Native albumin levels were increased throughout day 1-11 PE-A5% sessions (6.5±1.0 mg/ml to 10.2±1.4 mg/ml; p = 0.035). PE-A5% improved systemic hemodynamics (mean arterial pressure, heart rate, cardiac index), renal function (creatinine level, blood urea nitrogen), cerebral function (hepatic encephalopathy grade), liver parameters (transaminases, bilirubin) and inflammatory parameters (C-reactive protein, leukocyte count). All patients had at least one of the 78 AEs reported, mostly mild (product/procedure-related: 36%). Sixteen serious AEs were reported in eight patients (procedure/product-related: none). Conclusions: PE-A5% was a safe procedure associated with positive effects on albumin functionality, and circulatory, renal, cerebral, and liver function in patients with ACLF. Impact and implications: Acute-on-chronic liver failure (ACLF) is a clinical condition characterized by severe systemic inflammation, organ failure, and high mortality. Plasma exchange removes patient’s plasma containing pathogenic substances, replacing it with 5% albumin and fresh frozen plasma (PE-A5%). In this study, cirrhotic patients with ACLF were treated with PE-A5%, which was a safe procedure that increased binding and antioxidant capacity of patients’ albumin, while improving circulatory, kidney, brain, and liver functions. These beneficial effects could impact survival in ACLF. ClinicalTrials.gov Identifier: NCT01201720 EudraCT number: 2010-021360-15

Microbiota plays essential roles in the health, physiology, and in adaptation of marine multi-cellular organisms to their environment. In Antarctica, marine organisms have a wide range of unique physiological functions and adaptive strategies, useful for coping with extremely cold conditions. However, the role of microbiota associated with Antarctic organisms in such adaptive strategies is underexplored. In the present study, we investigated the diversity and putative functions of the microbiome of the sea star Odontaster validus, one of the main keystone species of the Antarctic benthic ecosystems. We compared the whole-body bacterial microbiome of sea stars from different sites of the Antarctic Peninsula and Ross Sea, two areas located in two opposite geographical sectors of the Antarctic continent. The taxonomic composition of O. validus microbiomes changed both between and within the two Antarctic sectors, suggesting that environmental and biological factors acting both at large and local scales may influence microbiome diversity. Despite this, one bacterial family (Rhodobacteraceae) was shared among all sea star individuals from the two geographical sectors, representing up to 95% of the microbial core, and suggesting a key functional role of this taxon in holobiont metabolism and well-being. In addition, the genus Roseobacter belonging to this family was also present in the surrounding sediment, implying a potential horizontal acquisition of dominant bacterial core taxa via host-selection processes from the environment.

The continuous outbreak of drug-resistant bacterial and viral infections imposes the need to search for new drug candidates. Natural products from marine bacteria still inspire the design of pharmaceuticals. Indeed, marine bacteria have unique metabolic flexibility to inhabit each ecological niche, thus expanding their biosynthetic ability to assemble unprecedented molecules. The One-Strain-Many-Compounds approach and tandem mass spectrometry allowed the discovery of a Shewanella aquimarina strain as a source of novel imidazolium alkaloids via molecular networking. The alkaloid mixture was shown to exert bioactivities such as: (a) antibacterial activity against antibiotic-resistant Staphylococcus aureus clinical isolates at 100 µg/mL, (b) synergistic effects with tigecycline and linezolid, (c) restoration of MRSA sensitivity to fosfomycin, and (d) interference with the biofilm formation of S. aureus 6538 and MRSA. Moreover, the mixture showed antiviral activity against viruses with and without envelopes. Indeed, it inhibited the entry of coronavirus HcoV-229E and herpes simplex viruses into human cells and inactivated poliovirus PV-1 in post-infection assay at 200 µg/mL. Finally, at the same concentration, the fraction showed anthelminthic activity against Caenorhabditis elegans, causing 99% mortality after 48 h. The broad-spectrum activities of these compounds are partially due to their biosurfactant behavior and make them promising candidates for breaking down drug-resistant infectious diseases.

During scientific expeditions in Indonesia and Vietnam, several sponge specimens belonging to the genus Cladocroce were collected. The integration of morphological and molecular analyses, incorporating species delimitation models (ABGD, ASAP, and bPTP) and phylogenetic approaches using three molecular markers (COI, 28S, and 18S–ITS1–5.8S–ITS2–28S), allowed us to discriminate three congeneric species. Two of these species (C. burapha and C. pansinii sp. nov.) were supported by morphological and molecular data, whereas a third species (C. lamellata sp. nov.) was delimited by morphological data only. We formally describe two new species, C. pansinii sp. nov. and C. lamellata sp. nov. C. aculeata is a newly recorded species for Indonesia and the first documented finding after the original description. The re-examination of the type material of C. burapha, and indirectly the molecular approach, allowed us to confirm that C. burapha lives in sympatry with C. pansinii sp. nov. in Vietnam and with C. lamellata in Indonesia. Thanks to these findings, we relocated the paratype of C. burapha to the new species described here, i.e., C. pansinii sp. nov.

Objectives:. This study aims to determine similarities and differences in clinical characteristics between the patients from two waves of severe acute respiratory syndrome coronavirus-2 infection at the time of hospital admission, as well as to identify risk biomarkers of coronavirus disease 2019 severity. Design:. Retrospective observational study. Setting:. A single tertiary-care center in Madrid. Patients:. Coronavirus disease 2019 adult patients admitted to hospital from March 4, 2020, to March 25, 2020 (first infection wave), and during July 18, 2020, and August 20, 2020 (second infection wave). Interventions:. Treatment with a hospital-approved drug cocktail during hospitalization. Measurements and Main Results:. Demographic, clinical, and laboratory data were compared between the patients with moderate and critical/fatal illness across both infection waves. The median age of patients with critical/fatal coronavirus disease 2019 was 67.5 years (interquartile range, 56.75–78.25 yr; 64.5% male) in the first wave and 59.0 years (interquartile range, 48.25–80.50 yr; 70.8% male) in the second wave. Hypertension and dyslipidemia were major comorbidities in both waves. Body mass index over 25 and presence of bilateral pneumonia were common findings. Univariate logistic regression analyses revealed an association of a number of blood parameters with the subsequent illness progression and severity in both waves. However, some remarkable differences were detected between both waves that prevented an accurate extrapolation of prediction models from the first wave into the second wave. Interleukin-6 and d-dimer concentrations at the time of hospital admission were remarkably higher in patients who developed a critical/fatal condition only during the first wave (p < 0.001), although both parameters significantly increased with disease worsening in follow-up studies from both waves. Multivariate analyses from wave 1 rendered a predictive signature for critical/fatal illness upon hospital admission that comprised six blood biomarkers: neutrophil-to-lymphocyte ratio (≥ 5; odds ratio, 2.684 [95% CI, 1.143–6.308]), C-reactive protein (≥ 15.2 mg/dL; odds ratio, 2.412 [95% CI, 1.006–5.786]), lactate dehydrogenase (≥ 411.96 U/L; odds ratio, 2.875 [95% CI, 1.229–6.726]), interleukin-6 (≥ 78.8 pg/mL; odds ratio, 5.737 [95% CI, 2.432–13.535]), urea (≥ 40 mg/dL; odds ratio, 1.701 [95% CI, 0.737–3.928]), and d-dimer (≥ 713 ng/mL; odds ratio, 1.903 [95% CI, 0.832–4.356]). The predictive accuracy of the signature was 84% and the area under the receiver operating characteristic curve was 0.886. When the signature was validated with data from wave 2, the accuracy was 81% and the area under the receiver operating characteristic curve value was 0.874, albeit most biomarkers lost their independent significance. Follow-up studies reassured the importance of monitoring the biomarkers included in the signature, since dramatic increases in the levels of such biomarkers occurred in critical/fatal patients over disease progression. Conclusions:. Most parameters analyzed behaved similarly in the two waves of coronavirus disease 2019. However, univariate logistic regression conducted in both waves revealed differences in some parameters associated with poor prognosis in wave 1 that were not found in wave 2, which may reflect a different disease stage of patients on arrival to hospital. The six-biomarker predictive signature reported here constitutes a helpful tool to classify patient’s prognosis on arrival to hospital.

Host-microbe interactions play crucial roles in marine ecosystems. However, we still have very little understanding of the mechanisms that govern these relationships, the evolutionary processes that shape them, and their ecological consequences. The holobiont concept is a renewed paradigm in biology that can help to describe and understand these complex systems. It posits that a host and its associated microbiota with which it interacts, form a holobiont, and have to be studied together as a coherent biological and functional unit to understand its biology, ecology, and evolution. Here we discuss critical concepts and opportunities in marine holobiont research and identify key challenges in the field. We highlight the potential economic, sociological, and environmental impacts of the holobiont concept in marine biological, evolutionary, and environmental sciences. Given the connectivity and the unexplored biodiversity specific to marine ecosystems, a deeper understanding of such complex systems requires further technological and conceptual advances, e.g., the development of controlled experimental model systems for holobionts from all major lineages and the modeling of (info)chemical-mediated interactions between organisms. Here we propose that one significant challenge is to bridge cross-disciplinary research on tractable model systems in order to address key ecological and evolutionary questions. This first step is crucial to decipher the main drivers of the dynamics and evolution of holobionts and to account for the holobiont concept in applied areas, such as the conservation, management, and exploitation of marine ecosystems and resources, where practical solutions to predict and mitigate the impact of human activities are more important than ever.

Native grasslands are the main source of food for livestock in the Campos region of South America. These forage resources are heterogeneous in species composition, grazing management, and soil fertility within a context of variable climate, all of which are factors that affect forage crude protein content over time and space. Despite the importance of protein in livestock nutrition, there is a gap in the knowledge of how fertilisation, sward height, and soil water availability influence the crude protein content of these grasslands. We used data from a long-term fertilisation experiment to construct a structural model aiming to identify the main factors influencing forage crude protein content of a basaltic native grassland in northern Uruguay. The structural model revealed that both fertilisation and the increase in soil water availability (through the improvement of the nitrogen content of green leaves) are the main pathways by which forage crude protein content increases. This new approach (which identifies and quantifies the main factors that drive forage crude protein content of native grasslands) could be used to support prediction models for forage protein content in order to improve grazing livestock nutrition of Campos native grasslands.

Cahong in Ha Long Bay (Vietnam) is a small lake with a reduced, invisible connection with the open sea. The water column conditions locally experience notable fluctuations across the year, mostly driven by biannual monsoon seasons. Salinity, temperature, and pH often reach extreme values, unsustainable for the majority of the marine fauna. Therefore, the biodiversity of the benthic macrofauna in this peculiar habitat is remarkably low. In particular, a single sponge species new to science was found solely populating this characteristic brackish lake during our last survey in August 2018. Spongilla manconiae sp. nov. is a new Porifera species described here. It belongs to an exclusively freshwater taxon and seems to have acquired adaptive traits to tolerate extreme peaks of temperature and salinity. The mitochondrial Cytochrome C Oxidase subunit 1 (COI) and the nuclear Internal Transcribed Spacers 1 and 2 (ITSs) gene markers were used for barcoding tagging and phylogenetic analyses. The new species revealed large genetic distances and separate clustering in the tree topology, with respect to other reference spongillid sequences from various geographic areas. The study provides evidence for an urgency to protect these unique marine lake systems because they represent rare, fluctuant, fragile habitats that may speed up speciation processes.

Polar marine biota have adapted to thrive under one of the ocean’s most inhospitable scenarios, where extremes of temperature, light photoperiod and ice disturbance, along with ecological interactions, have selected species with a unique suite of secondary metabolites. Organisms of Arctic and Antarctic oceans are prolific sources of natural products, exhibiting wide structural diversity and remarkable bioactivities for human applications. Chemical skeletons belonging to terpene families are the most commonly found compounds, whereas cytotoxic antimicrobial properties, the capacity to prevent infections, are the most widely reported activities from these environments. This review firstly summarizes the regulations on access and benefit sharing requirements for research in polar environments. Then it provides an overview of the natural product arsenal from Antarctic and Arctic marine organisms that displays promising uses for fighting human disease. Microbes, such as bacteria and fungi, and macroorganisms, such as sponges, macroalgae, ascidians, corals, bryozoans, echinoderms and mollusks, are the main focus of this review. The biological origin, the structure of terpenes and terpenoids, derivatives and their biotechnological potential are described. This survey aims to highlight the chemical diversity of marine polar life and the versatility of this group of biomolecules, in an effort to encourage further research in drug discovery.

La trombosis venosa profunda y el tromboembolismo pulmonar son dos presentaciones de la misma enfermedad, la enfermedad tromboembólica venosa. Su alta incidencia entre la población anciana junto con numerosos factores de riesgo asociados y la dificultad del diagnóstico hacen de esta un importante problema de salud con afectación directa sobre el profesional enfermero. Método: revisión de la literatura científica, incluyendo artículos publicados entre 1993 y 2013. Conclusiones: la incidencia de las enfermedades tromboembólicas se ve incrementada con la edad. Esta es aún mayor en personas que presentan factores de riesgo tales como, inmovilidad, cáncer y cirugía. Un diagnóstico y tratamiento precoz ayuda a disminuir las complicaciones y casos de mortalidad.

Many bioactive products from benthic invertebrates mediating ecological interactions have proved to reduce predation, but their mechanisms of action, and their molecular identities, are usually unknown. It was suggested, yet scarcely investigated, that nutritional quality interferes with defensive metabolites. This means that antifeedants would be less effective when combined with energetically rich prey, and that higher amounts of defensive compounds would be needed for predator avoidance. We evaluated the effects of five types of repellents obtained from Antarctic invertebrates, in combination with diets of different energetic values. The compounds came from soft corals, ascidians and hexactinellid sponges; they included wax esters, alkaloids, a meroterpenoid, a steroid, and the recently described organic acid, glassponsine. Feeding repellency was tested through preference assays by preparing diets (alginate pearls) combining different energetic content and inorganic material. Experimental diets contained various concentrations of each repellent product, and were offered along with control compound-free pearls, to the Antarctic omnivore amphipod Cheirimedon femoratus. Meridianin alkaloids were the most active repellents, and wax esters were the least active when combined with foods of distinct energetic content. Our data show that levels of repellency vary for each compound, and that they perform differently when mixed with distinct assay foods. The natural products that interacted the most with energetic content were those occurring in nature at higher concentrations. The bioactivity of the remaining metabolites tested was found to depend on a threshold concentration, enough to elicit feeding repellence, independently from nutritional quality.

Generalist predation constitutes a driving force for the evolution of chemical defences. In the Antarctic benthos, asteroids and omnivore amphipods are keystone opportunistic predators. Sessile organisms are therefore expected to develop defensive mechanisms mainly against such consumers. However, the different habits characterizing each predator may promote variable responses in prey. Feeding-deterrence experiments were performed with the circumpolar asteroid macropredator Odontaster validus to evaluate the presence of defences within the apolar lipophilic fraction of Antarctic invertebrates and macroalgae. A total of 51% of the extracts were repellent, yielding a proportion of 17 defended species out of the 31 assessed. These results are compared with a previous study in which the same fractions were offered to the abundant circum-Antarctic amphipod Cheirimedon femoratus. Overall, less deterrence was reported towards asteroids (51%) than against amphipods (80.8%), principally in sponge and algal extracts. Generalist amphipods, which establish casual host–prey sedentary associations with biosubstrata (preferentially sponges and macroalgae), may exert more localized predation pressure than sea stars on certain sessile prey, which would partly explain these results. The nutritional quality of prey may interact with feeding deterrents, whose production is presumed to be metabolically expensive. Although optimal defence theory posits that chemical defences are managed and distributed as to guarantee protection at the lowest cost, we found that only a few organisms localized feeding deterrents towards most exposed and/or valuable body regions. Lipophilic defensive metabolites are broadly produced in Antarctic communities to deter opportunistic predators, although several species combine different defensive traits.

The sponge fauna has been largely overlooked in the Archipelago of Hawai'i, notwithstanding the paramount role of this taxon in marine ecosystems. The lack of knowledge about Porifera populations inhabiting the Hawai'ian reefs limits the development of ecological studies aimed at understanding the functioning of these marine systems. Consequently, this project addresses this gap by describing the most representative sponge species in the shallow waters of the enigmatic bay of Kane'ohe Bay, in O'ahu Island. A total of 30 species (28 demosponges and two calcareous sponges) living associated to the reef structures are here reported. Six of these species are new records to the Hawai'ian Porifera catalogue and are suspected to be recent introductions to these islands. Morphological descriptions of the voucher specimens are provided, along with sequencing data of two partitions involving the mitochondrial cytochrome oxidase subunit 1 (COI) marker and a fragment covering partial (18S and 28S) and full (ITS-1, 5.8S and ITS-2) nuclear ribosomal genes. Species delimitations based on genetic distances were calculated to valitate how taxonomic assignments from DNA barcoding aligned with morphological identifications. Of the 60 sequences submitted to GenBank ~88% are the first sequencing records for the corresponding species and genetic marker. This work compiles the first catalogue combining morphological characters with DNA barcoding of Hawai'ian sponges, and contributes to the repository of public databases through the Sponge Barcoding Project initiative.

Ascidians have developed multiple defensive strategies mostly related to physical, nutritional or chemical properties of the tunic. One of such is chemical defense based on secondary metabolites. We analyzed a series of colonial Antarctic ascidians from deep-water collections belonging to the genera Aplidium and Synoicum to evaluate the incidence of organic deterrents and their variability. The ether fractions from 15 samples including specimens of the species A. falklandicum, A. fuegiense, A. meridianum, A. millari and S. adareanum were subjected to feeding assays towards two relevant sympatric predators: the starfish Odontaster validus, and the amphipod Cheirimedon femoratus. All samples revealed repellency. Nonetheless, some colonies concentrated defensive chemicals in internal body-regions rather than in the tunic. Four ascidian-derived meroterpenoids, rossinones B and the three derivatives 2,3-epoxy-rossinone B, 3-epi-rossinone B, 5,6-epoxy-rossinone B, and the indole alkaloids meridianins A–G, along with other minoritary meridianin compounds were isolated from several samples. Some purified metabolites were tested in feeding assays exhibiting potent unpalatabilities, thus revealing their role in predation avoidance. Ascidian extracts and purified compound-fractions were further assessed in antibacterial tests against a marine Antarctic bacterium. Only the meridianins showed inhibition activity, demonstrating a multifunctional defensive role. According to their occurrence in nature and within our colonial specimens, the possible origin of both types of metabolites is discussed.

Solar radiation represents a key abiotic factor in the evolution of life in the oceans. In general, marine, biota—particularly in euphotic and dysphotic zones—depends directly or indirectly on light, but ultraviolet radiation (UV-R) can damage vital molecular machineries. UV-R induces the formation of reactive oxygen species (ROS) and impairs intracellular structures and enzymatic reactions. It can also affect organismal physiologies and eventually alter trophic chains at the ecosystem level. In Antarctica, physical drivers, such as sunlight, sea-ice, seasonality and low temperature are particularly influencing as compared to other regions. The springtime ozone depletion over the Southern Ocean makes organisms be more vulnerable to UV-R. Nonetheless, Antarctic species seem to possess analogous UV photoprotection and repair mechanisms as those found in organisms from other latitudes. The lack of data on species-specific responses towards increased UV-B still limits the understanding about the ecological impact and the tolerance levels related to ozone depletion in this region. The photobiology of Antarctic biota is largely unknown, in spite of representing a highly promising reservoir in the discovery of novel cosmeceutical products. This review compiles the most relevant information on photoprotection and UV-repair processes described in organisms from the Southern Ocean, in the context of this unique marine polar environment.

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Abstract There are few studies assessing psychological burden and quality of life (QoL) in caregivers of pediatric patients with nephropathic cystinosis, a severe chronic disease. This observational, single-center study aimed to explore the levels of anxiety, depression, care burden, and QoL status in caregivers of patients with nephropathic cystinosis. The Hospital Anxiety and Depression Scale (HADS), the Zarit Caregiver Burden Scale, and the Short Form-36 (SF-36) were administered to caregivers of pediatric patients with nephropathic cystinosis. Nine caregivers of pediatric patients with nephropathic cystinosis participated in the study (6 boys and 3 girls; mean age, 12.6 ± 4.2 years). All participating caregivers were the patient’s mothers. Of the 9 caregivers, 6 showed anxiety/depression and 4 severe care burden. Overall, SF-36 QoL domains with a worse perception by caregivers were ‘general health’ and ‘health change over time’. Mothers without depression/anxiety and low care burden had better QoL perception (p = 0.02). All caregivers with high care burden showed anxiety/depression. In our study cohort, caregivers of pediatric patients with nephropathic cystinosis showed high levels of anxiety/depression, high care burden, and impaired QoL, highlighting the importance of detecting psycho-social issues to implement strategies that relieve family stress and improve coping strategies.

Abstract Quantitative MR imaging is becoming more feasible to be used in clinical work since new approaches have been proposed in order to substantially accelerate the acquisition and due to the possibility of synthetically deriving weighted images from the parametric maps. However, their applicability has to be thoroughly validated in order to be included in clinical practice. In this pilot study, we acquired Magnetic Resonance Image Compilation scans to obtain T1, T2 and PD maps in 14 glioma patients. Abnormal tissue was segmented based on conventional images and using a deep learning segmentation technique to define regions of interest (ROIs). The quantitative T1, T2 and PD values inside ROIs were analyzed using the mean, the standard deviation, the skewness and the kurtosis and compared to the quantitative T1, T2 and PD values found in normal white matter. We found significant differences in pre-contrast T1 and T2 values between abnormal tissue and healthy tissue, as well as between T1w-enhancing and non-enhancing regions. ROC analysis was used to evaluate the potential of quantitative T1 and T2 values for voxel-wise classification of abnormal/normal tissue (AUC = 0.95) and of T1w enhancement/non-enhancement (AUC = 0.85). A cross-validated ROC analysis found high sensitivity (73%) and specificity (73%) with AUCs up to 0.68 on the a priori distinction between abnormal tissue with and without T1w-enhancement. These results suggest that normal tissue, abnormal tissue, and tissue with T1w-enhancement are distinguishable by their pre-contrast quantitative values but further investigation is needed.

Abstract We present and evaluate a new insight into magnetic resonance imaging (MRI). It is based on the algebraic description of the magnetization during the transient response—including intrinsic magnetic resonance parameters such as longitudinal and transverse relaxation times (T1, T2) and proton density (PD) and experimental conditions such as radiofrequency field (B1) and constant/homogeneous magnetic field (B0) from associated scanners. We exploit the correspondence among three different elements: the signal evolution as a result of a repetitive sequence of blocks of radiofrequency excitation pulses and encoding gradients, the continuous Bloch equations and the mathematical description of a sequence as a linear system. This approach simultaneously provides, in a single measurement, all quantitative parameters of interest as well as associated system imperfections. Finally, we demonstrate the in-vivo applicability of the new concept on a clinical MRI scanner.

Background The role of bronchoscopy in coronavirus disease 2019 (COVID-19) is a matter of debate. Patients and methods This observational multicentre study aimed to analyse the prognostic impact of bronchoscopic findings in a consecutive cohort of patients with suspected or confirmed COVID-19. Patients were enrolled at 17 hospitals from February to June 2020. Predictors of in-hospital mortality were assessed by multivariate logistic regression. Results A total of 1027 bronchoscopies were performed in 515 patients (age 61.5±11.2 years; 73% men), stratified into a clinical suspicion cohort (n=30) and a COVID-19 confirmed cohort (n=485). In the clinical suspicion cohort, the diagnostic yield was 36.7%. In the COVID-19 confirmed cohort, bronchoscopies were predominantly performed in the intensive care unit (n=961; 96.4%) and major indications were: difficult mechanical ventilation (43.7%), mucus plugs (39%) and persistence of radiological infiltrates (23.4%). 147 bronchoscopies were performed to rule out superinfection, and diagnostic yield was 42.9%. There were abnormalities in 91.6% of bronchoscopies, the most frequent being mucus secretions (82.4%), haematic secretions (17.7%), mucus plugs (17.6%), and diffuse mucosal hyperaemia (11.4%). The independent predictors of in-hospital mortality were: older age (OR 1.06; p

I launched Sharp Scratch with The BMJ’s multimedia team in the spring of 2019, during my year running all things student at the world’s fourth leading medical journal. It’s a podcast where medical students, newly qualified doctors, and expert guests meet in a studio to talk about the things we need to know to be good doctors but that we may not learn at medical school. I’ve since returned to medical school and joined a new year group, where I often find myself in a circle of strangers. Many times in the last 12 months, the professionalism strand of my medical degree has put me in a circle with students I have met once or twice to discuss personal stories and to reflect. Many of the stories are familiar. The student with mental health problems shadowing an intimidating doctor on placement who feels unable to disclose their needs. The delirious or psychotic patient who inappropriately comments on a student’s appearance. The student who overhears a joke about a patient and feels a line has been crossed. And a general anxiety about a future career where we will have to respond well in situations even more complex than these. When I’m in a circle of reflecting students, I don’t always say what I’m thinking. But I’m usually thinking about an episode of Sharp Scratch.

(1) Background: Polycystic liver disease (PLD) is a heterogeneous group of congenital disorders characterized by bile duct dilatation and cyst development derived from cholangiocytes. Nevertheless, the cystogenesis mechanism is currently unknown and the PLD treatment is limited to liver transplantation. Novel and efficient therapeutic approaches are th6us needed. In this context, the present work has a principal aim to find novel molecular pathways, as well as new therapeutic targets, involved in the hepatic cystogenesis process. (2) Methods: Quantitative proteomics based on SWATH–MS technology were performed comparing hepatic proteomes of Wild Type and mutant/polycystic livers in a polycystic kidney disease (PKD) murine model (Pkd1cond/cond;Tam-Cre−/+). (3) Results: We identified several proteins altered in abundance, with two-fold cut-off up-regulation or down-regulation and an adjusted p-value significantly related to hepatic cystogenesis. Then, we performed enrichment and a protein–protein analysis identifying a cluster focused on hepatic fibrinogens. Finally, we validated a selection of targets by RT-qPCR, Western blotting and immunohistochemistry, finding a high correlation with quantitative proteomics data and validating the fibrinogen complex. (4) Conclusions: This work identified a novel molecular pathway in cystic liver disease, highlighting the fibrinogen complex as a possible new therapeutic target for PLD.

Objective. To compare the thickness of corneal layers, specifically the Descemet’s membrane (DM), in normal corneas and in failed grafts due to rejection (FGRs) using the digital histopathology and to propose a model for the measurement of corneal layers using this method. Methods. This is a prospective, cross-sectional study performed at the MUHC-McGill University Ocular Pathology & Translational Research Laboratory (McGill University, Montreal, Canada). Histopathological sections of 25 normal human corneas and 40 FGRs were fully digitalized and examined. Inclusion criteria: samples diagnosed as normal corneas or FGRs, from patients older than 18 years of age. Exclusion criteria: histopathological sections without adequate tissue or missing epidemiological information. For each sample, the thicknesses of the epithelium, stroma, and DM were acquired. From a perpendicular plane of reference, two central measurements and two nasal and two temporal peripheral measurements were obtained. Results. There were differences between the normal and FGR groups in the mean central thickness of the epithelium (p

BackgroundA simple method to assess renal function is the estimated glomerular filtration rate, and it shows prognostic implications. However, it remains unknown which equation should be used in patients with acute coronary syndrome. We compared the ability and correlation of the Cockcroft‐Gault, Modification of Diet in Renal Disease‐4 (MDRD‐4), and Chronic Kidney Disease Epidemiology Collaboration (CKD‐EPI) equations and their predictive performance for major adverse cardiovascular events, all‐cause mortality, and major bleeding in a cohort of patients with acute coronary syndrome. Methods and ResultsMulticenter prospective registry involving 1699 consecutive patients with acute coronary syndrome from 3 tertiary institutions. At entry, renal function was assessed using the Cockcroft‐Gault, MDRD‐4, and CKD‐EPI‐creatinine equations. During 12 months of follow‐up, we recorded all major adverse cardiovascular events (composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal ischemic stroke), bleeding events (Bleeding Academic Research Consortium classification), and all‐cause mortality. Receiver operating characteristic curve comparisons demonstrated that Cockcroft‐Gault equation had higher predictive ability compared with MDRD‐4 equation for major adverse cardiovascular events (0.651 versus 0.616; P=0.023), major bleeding (0.600 versus 0.551; P=0.005), and all‐cause mortality (0.754 versus 0.717; P=0.033), as well as higher predictive ability compared with CKD‐EPI equation for major bleeding (0.600 versus 0.564; P=0.018). Integrated discrimination improvement and net reclassification improvement analyses showed superior discrimination and reclassification of Cockcroft‐Gault equation. Decision curve analyses graphically demonstrated higher net benefit and clinical usefulness of the Cockcroft‐Gault equation in comparison with MDRD‐4 and CKD‐EPI equations. ConclusionsIn patients with acute coronary syndrome, the Cockcroft‐Gault equation presented superior predictive ability for major adverse cardiovascular events, major bleeding, and all‐cause mortality compared with MDRD‐4 equation, and superior predictive ability for major bleeding compared with CKD‐EPI equation. The Cockcroft‐Gault equation also showed higher net benefit and clinical usefulness.