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Sponges are the most basal metazoan phylum1 and may have played important roles in modulating the redox architecture of Neoproterozoic oceans2. Although molecular clocks predict that sponges diverged in the Neoproterozoic era3,4, their fossils have not been unequivocally demonstrated before the Cambrian period5-8, possibly because Precambrian sponges were aspiculate and non-biomineralized9. Here we describe a late-Ediacaran fossil, Helicolocellus cantori gen. et sp. nov., from the Dengying Formation (around 551-539 million years ago) of South China. This fossil is reconstructed as a large, stemmed benthic organism with a goblet-shaped body more than 0.4 m in height, with a body wall consisting of at least three orders of nested grids defined by quadrate fields, resembling a Cantor dust fractal pattern. The resulting lattice is interpreted as an organic skeleton comprising orthogonally arranged cruciform elements, architecturally similar to some hexactinellid sponges, although the latter are built with biomineralized spicules. A Bayesian phylogenetic analysis resolves H. cantori as a crown-group sponge related to the Hexactinellida. H. cantori confirms that sponges diverged and existed in the Precambrian as non-biomineralizing animals with an organic skeleton. Considering that siliceous biomineralization may have evolved independently among sponge classes10-13, we question the validity of biomineralized spicules as a necessary criterion for the identification of Precambrian sponge fossils.
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Fósseis , Poríferos , Animais , Teorema de Bayes , China , Filogenia , Poríferos/anatomia & histologia , Poríferos/classificaçãoRESUMO
BACKGROUND: Cardiac 18F-fluorodeoxyglucose (FDG)-PET-CT plays an important role in the assessment of cardiovascular diseases. Effective management of urgent scan findings facilitates optimal patient care. METHODS: We characterised the management of urgent, expected and unexpected findings in patients referred for cardiac [18F]fluorodeoxyglucose integrated with computed tomography (FDG-PET-CT) at the Royal Brompton Hospital (United Kingdom). Urgent findings are escalated by the reporting physicians/radiologists raising RadAlert notifications to the referring clinician. We characterised the indications and time to management (TTM) between the RadAlert and the resulting management. As controls, we characterised the TTM of 33 urgent findings identified before the RadAlert system was implemented. RESULTS: Of the 1497 consecutive FDG-PET-CT scans screened (April 2021 to February 2023), 93 RadAlerts were suitable for analysis (TTM 7 days [interquartile range: 2-14]). Expected urgent findings included active cardiac sarcoidosis (56%; TTM 8 days [5-18]), heart transplant rejection (12%; 6 ± 4 days), infective endocarditis (9%; 2 days [1-12]), cardiac device infections (5%; 1 day [0-2]), acute myocarditis (2%; 5 and 14 days) and epicardial mass (1%; 1 day). TTM did not differ significantly between indications (P = 0.06). RadAlert cases had significantly shorter TTM than controls without RadAlert, P = 0.001. After the RadAlerts, 81% of patients had clinical reviews, and 55% had escalation of medical/surgical therapies. Unexpected findings (total N = 45; median TTM 6 days [1-10]) included malignancies (N = 3), infections (N = 2), pneumothorax (N = 1), benign diagnosis (N = 30), unclear diagnosis (N = 5) and 4 findings disappeared on repeat imaging. CONCLUSIONS: Cardiac FDG-PET-CT identifies expected and unexpected findings in a range of cardiovascular diseases. Serious, unexpected findings are rare and can be effectively escalated by the RadAlert system.
Assuntos
Doenças Cardiovasculares , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Doenças Cardiovasculares/diagnóstico por imagem , Idoso , Adulto , Achados IncidentaisRESUMO
Food-related studies often categorize foods using criteria such as fat and sugar content (e.g., high-fat, high-sugar foods; low-fat, low-sugar foods), and use these categorizations for further analyses. While these criteria are relevant to nutritional health, it is unclear whether they agree with the ways in which we typically group foods. Do these objective categories correspond to our subjective sense? To address this question, we recruited a group of 487 online participants to perform a triplet comparison task involving implicit object similarity judgements on images of 36 foods, which varied in their levels of fat and sugar. We also acquired subjective ratings of other food properties from another set of 369 online participants. Data from the online triplet task was used to generate a similarity matrix of these 36 foods. Principal Components Analysis (PCA) of this matrix identified that the strongest determinant of food similarity (the first PC) was most highly related to participants' judgements of how processed the foods were, while the second component was most related to estimates of sugar and fat content. K-means clustering analysis revealed five emergent food groupings along these PC axes: sweets, fats, starches, fruits, and vegetables. Our results suggest that naturalistic categorizations of food are driven primarily by knowledge of the origin of foods (i.e., grown or manufactured), rather than by their sensory or macronutrient properties. These differences should be considered and explored when developing methods for scientific food studies.
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In patients with sarcoidosis, the development of pulmonary hypertension is associated with significant morbidity and mortality. The global prevalence of sarcoidosis-associated pulmonary hypertension (SAPH) reportedly ranges between 2.9% and 20% of sarcoidosis patients. Multiple factors may contribute to the development of SAPH, including advanced parenchymal lung disease, severe systolic and/or diastolic left ventricular dysfunction, veno-occlusive or thromboembolic disease, as well as extrinsic factors such as pulmonary vascular compression from enlarged lymph nodes, anemia, and liver disease. Early diagnosis of SAPH is important but rarely achieved primarily due to insufficiently accurate screening strategies, which rely entirely on non-invasive tests and clinical assessment. The definitive diagnosis of SAPH requires right heart catheterization (RHC), with transthoracic echocardiography as the recommended gatekeeper to RHC according to current guidelines. A 6-min walk test (6MWT) had the greatest prognostic value in SAPH patients based on recent registry outcomes, while advanced lung disease determined using a reduced DLCO (<35% predicted) was associated with reduced transplant-free survival in pre-capillary SAPH. Clinical management involves the identification and treatment of the underlying mechanism. Pulmonary vasodilators are useful in several scenarios, especially when a pulmonary vascular phenotype predominates. End-stage SAPH may warrant consideration for lung transplantation, which remains a high-risk option. Multi-centered randomized controlled trials are required to develop existing therapies further and improve the prognosis of SAPH patients.
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Late Ediacaran strata from Newfoundland, Canada (~574-560 Ma) document near-census palaeocommunities of some of the earliest metazoans. Such preservation enables reproductive strategies to be inferred from the spatial distribution of populations of fossilized benthic organisms, previously revealing the existence of both propagule and stoloniferous reproductive modes among Ediacaran frondose taxa. Here, we describe 'conga lines': linear arrangements of more than three closely spaced fossil specimens. We calculate probabilistic models of point maps of 13 fossil-bearing bedding surfaces and show that four surfaces contain conga lines that are not the result of chance alignments. We then test whether these features could result from passive pelagic propagules settling in the lee of an existing frond, using computational fluid dynamics and discrete phase modelling. Under Ediacaran palaeoenvironmental conditions, preferential leeside settlement at the spatial scale of the conga lines is unlikely. We therefore conclude that these features are novel and do not reflect previously described reproductive strategies employed by Ediacaran organisms, suggesting the use of mixed reproductive strategies in the earliest animals. Such strategies enabled Ediacaran frondose taxa to act as reproductive generalists and may be an important facet of early metazoan evolution.
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In electrocatalysis, mechanistic analysis of reaction rate data often relies on the linearization of relatively simple rate equations; this is the basis for typical Tafel and reactant order dependence analyses. However, for more complex reaction phenomena, such as surface coverage effects or mixed control, these common linearization strategies will yield incomplete or uninterpretable results. Cohesive kinetic analysis, which is often used in thermocatalysis and involves quantitative model fitting for data collected over a wide range of reaction conditions, requires more data but also provides a more robust strategy for interrogating reaction mechanisms. In this work, we report a robotic system that improves the experimental workflow for collecting electrochemical rate data by automating sequential testing of up to 10 electrochemical cells, where each cell can have a different electrode, electrolyte, gas-phase reactant composition, and applied voltage. We used this system to investigate the mechanism of carbon dioxide electroreduction to carbon monoxide at several immobilized metal tetrapyrroles. Specifically, at cobalt phthalocyanine (CoPc), cobalt tetraphenylporphyrin (CoTPP), and iron phthalocyanine (FePc), we see signatures of complex reaction mechanisms, where observed bicarbonate and CO2 order dependences change with applied potential. We illustrate how phenomena such as electrolyte poisoning and potential-dependent degrees of rate control can explain the observed kinetic behaviors. Our mechanistic analysis suggests that CoPc and CoTPP share a similar reaction mechanism, akin to one previously proposed, whereas the mechanism for FePc likely involves a species later in the catalytic cycle as the most abundant reactive intermediate. Our study illustrates that complex reaction mechanisms that are not amenable to common Tafel and order dependence analyses may be quite prevalent across this class of immobilized metal tetrapyrrole electrocatalysts.
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BACKGROUND: There is a paucity of evidence on impact of a delay in Cardiac Sarcoidosis (CS) diagnosis after high-grade atrioventricular-block (AVB) and this study aims to fill this void. METHODS: Consecutive CS patients (n = 77) with high grade AVB referred to one specialist hospital in London between February 2007 to February 2023 were retrospectively reviewed. The median time from AVB to diagnosing CS (112 days) was used to define the Early (n = 38) and Late (n = 39) cohorts. The primary endpoint was a composite of all-cause mortality, cardiac transplantation, ventricular arrhythmic events or heart failure hospitalisation. Secondary endpoints included difference in maintenance prednisolone dose, need for cardiac device upgrade and device complications. RESULTS: The mean age of the cohort was 54.4 (±10.6) years of whom 64 % were male and 81 % Caucasian. After a mean follow up of 54.9 (±45.3) months, the primary endpoint was reached by more patients from the Late cohort (16/39 vs. 6/38, p = 0.02; multivariable HR 6.9; 95 %CI 1.5-32.2, p = 0.01). Early Group were more likely to have received an Implantable Cardioverter Defibrillator or Cardiac Resynchronisation Therapy-defibrillator as index device after AVB (19/38 vs. 6/39; p < 0.01) and had fewer device upgrades (19/38 vs. 30/39, p = 0.01) and a trend towards fewer device complications (1 vs. 5, p = 0.20). The maintenance dose of prednisolone was significantly higher in Late Group [20.7(±9.7) mg vs. 15.3(±7.9) mg, p = 0.02]. CONCLUSION: A late diagnosis of CS was associated with more adverse events, a greater probability of needing a device upgrade and required higher maintenance steroid dose.
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Bloqueio Atrioventricular , Cardiomiopatias , Sarcoidose , Humanos , Sarcoidose/diagnóstico , Sarcoidose/complicações , Masculino , Feminino , Bloqueio Atrioventricular/diagnóstico , Bloqueio Atrioventricular/terapia , Bloqueio Atrioventricular/etiologia , Pessoa de Meia-Idade , Cardiomiopatias/diagnóstico , Cardiomiopatias/terapia , Estudos Retrospectivos , Fatores de Tempo , Diagnóstico Precoce , Londres/epidemiologia , Prednisolona/uso terapêutico , Prednisolona/administração & dosagem , Adulto , Seguimentos , IdosoRESUMO
OBJECTIVES: Endocardial fibroelastosis (EFE) is a rare form of restrictive cardiomyopathy associated with high morbidity and mortality. The literature is sparse on information pertaining to risk stratification. Thus, we sought to highlight the risk factors of acute ischemic stroke (AIS) and mortality in adults with EFE. METHODS: The National Inpatient Sample (NIS) database was queried from 2001 to 2020 using the International Classification of Diseases 9th Revision (ICD-9) and 10th Revision (ICD-10) codes for adult patients with EFE. Factors associated with AIS and mortality were identified. RESULTS: In all, 18495 cases of EFE fit the inclusion criteria, of which 2370 (12.82%) had AIS. The mean ages for patients with and without AIS were 62.37 and 54.24, respectively. Multivariate regression suggested greater odds of AIS in patients with hypertension (aOR 2.329, P<0.01), dyslipidemia (aOR: 1.566, P<0.01), peripheral vascular disease (PVD) (aOR: 1.736, P<0.01), alcohol abuse (aOR: 1.817, P<0.01), age >60 y (aOR: 1.646, P<0.01), females (vs. males, aOR: 1.238, P<0.01), and smokers (aOR: 1.697, P<0.01). Patients with cirrhosis (aOR: 0.174, P<0.01), CKD (aOR: 0.369, P<0.01), COPD (aOR: 0.402, P<0.01), atrial fibrillation (aOR: 0.542, P<0.01) had lower odds of AIS. 3.1% of EFE patients with AIS died. Diabetes (aOR: 11.665, P<0.01) and COPD (aOR: 3.201, P=0.017) were associated with the greatest odds of all-cause mortality. Dyslipidemia (aOR: 0.387, P=0.010) and females (vs. males, aOR: 0.432, P=0.012) had reduced odds of all-cause mortality. CONCLUSION: Several risk factors are associated with AIS in EFE, while diabetes, COPD, and being male are associated with mortality in EFE.
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BACKGROUND: Cardiac sarcoidosis (CS) is an inflammatory condition that can present with heart failure (HF). Cardiac resynchronization therapy (CRT) is known to improve clinical outcomes for patients with left bundle branch block in the general HF population. However, data about the outcomes of CRT in CS is limited. METHODS: A systematic literature search was conducted using PubMed/Medline, Embase, and the Cochrane Library from inception to February 2024 to identify studies that reported clinical outcomes following the use of CRT in patients with CS. Data for outcomes was extracted, pooled, and analyzed. OpenMetaAnalyst was used for pooling untransformed proportions along with the corresponding 95 % confidence intervals (CIs). RESULTS: Five studies with a total of 176 CS patients who received CRT were included. The pooled incidence for all-cause mortality was 7.6 % (95 % CI: -3 % to 18 %), for HF-related hospitalizations 23.2 % (95 % CI: 2 % to 43 %), and for major adverse cerebral and cardiovascular events 27 % (95 % CI: 8 % to 45 %) after a mean follow-up of 60.1 (±48.7) months. The pooled left ventricular ejection fraction (LVEF) was 34.28 % (95 % CI: 29.88 % to 38.68 %) demonstrating an improvement of 3.75 % in LVEF from baseline LVEF of 30.58 % (95 % CI: 24.68 % to 36.48 %). The mean New York Heart Association (NYHA) functional class was 2.16 (95 % CI: 1.47 to 2.84) after CRT as compared to the baseline mean NYHA of 2.58 (95 % CI: 2.29 to 2.86). CONCLUSION: Although improvements were observed in LVEF and mean NYHA, mortality was high in CS patients with CRT.