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1.
Nature ; 619(7971): 716-719, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37216978

RESUMO

The extremely rapid assembly of the earliest galaxies during the first billion years of cosmic history is a major challenge for our understanding of galaxy formation physics1-5. The advent of the James Webb Space Telescope (JWST) has exacerbated this issue by confirming the existence of galaxies in substantial numbers as early as the first few hundred million years6-8. Perhaps even more surprisingly, in some galaxies, this initial highly efficient star formation rapidly shuts down, or quenches, giving rise to massive quiescent galaxies as little as 1.5 billion years after the Big Bang9,10. However, due to their faintness and red colour, it has proven extremely challenging to learn about these extreme quiescent galaxies, or to confirm whether any existed at earlier times. Here we report the spectroscopic confirmation of a massive quiescent galaxy, GS-9209, at redshift, z = 4.658, just 1.25 billion years after the Big Bang, using the JWST Near-Infrared Spectrograph (NIRSpec). From these data we infer a stellar mass of M* = 3.8 ± 0.2 × 1010 M⊙, which formed over a roughly 200 Myr period before this galaxy quenched its star-formation activity at [Formula: see text], when the Universe was approximately 800 Myr old. This galaxy is both a likely descendent of the highest-redshift submillimetre galaxies and quasars, and a likely progenitor for the dense, ancient cores of the most massive local galaxies.

2.
Nature ; 622(7984): 707-711, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37579792

RESUMO

During the first 500 million years of cosmic history, the first stars and galaxies formed, seeding the Universe with heavy elements and eventually reionizing the intergalactic medium1-3. Observations with the James Webb Space Telescope (JWST) have uncovered a surprisingly high abundance of candidates for early star-forming galaxies, with distances (redshifts, z), estimated from multiband photometry, as large as z ≈ 16, far beyond pre-JWST limits4-9. Although such photometric redshifts are generally robust, they can suffer from degeneracies and occasionally catastrophic errors. Spectroscopic measurements are required to validate these sources and to reliably quantify physical properties that can constrain galaxy formation models and cosmology10. Here we present JWST spectroscopy that confirms redshifts for two very luminous galaxies with z > 11, and also demonstrates that another candidate with suggested z ≈ 16 instead has z = 4.9, with an unusual combination of nebular line emission and dust reddening that mimics the colours expected for much more distant objects. These results reinforce evidence for the early, rapid formation of remarkably luminous galaxies while also highlighting the necessity of spectroscopic verification. The large abundance of bright, early galaxies may indicate shortcomings in current galaxy formation models or deviations from physical properties (such as the stellar initial mass function) that are generally believed to hold at later times.

3.
Nature ; 601(7894): 542-548, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35082418

RESUMO

Obtaining a burning plasma is a critical step towards self-sustaining fusion energy1. A burning plasma is one in which the fusion reactions themselves are the primary source of heating in the plasma, which is necessary to sustain and propagate the burn, enabling high energy gain. After decades of fusion research, here we achieve a burning-plasma state in the laboratory. These experiments were conducted at the US National Ignition Facility, a laser facility delivering up to 1.9 megajoules of energy in pulses with peak powers up to 500 terawatts. We use the lasers to generate X-rays in a radiation cavity to indirectly drive a fuel-containing capsule via the X-ray ablation pressure, which results in the implosion process compressing and heating the fuel via mechanical work. The burning-plasma state was created using a strategy to increase the spatial scale of the capsule2,3 through two different implosion concepts4-7. These experiments show fusion self-heating in excess of the mechanical work injected into the implosions, satisfying several burning-plasma metrics3,8. Additionally, we describe a subset of experiments that appear to have crossed the static self-heating boundary, where fusion heating surpasses the energy losses from radiation and conduction. These results provide an opportunity to study α-particle-dominated plasmas and burning-plasma physics in the laboratory.

4.
Circ Res ; 135(1): 60-75, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38770652

RESUMO

BACKGROUND: Pathogenic concepts of right ventricular (RV) failure in pulmonary arterial hypertension focus on a critical loss of microvasculature. However, the methods underpinning prior studies did not take into account the 3-dimensional (3D) aspects of cardiac tissue, making accurate quantification difficult. We applied deep-tissue imaging to the pressure-overloaded RV to uncover the 3D properties of the microvascular network and determine whether deficient microvascular adaptation contributes to RV failure. METHODS: Heart sections measuring 250-µm-thick were obtained from mice after pulmonary artery banding (PAB) or debanding PAB surgery and properties of the RV microvascular network were assessed using 3D imaging and quantification. Human heart tissues harvested at the time of transplantation from pulmonary arterial hypertension cases were compared with tissues from control cases with normal RV function. RESULTS: Longitudinal 3D assessment of PAB mouse hearts uncovered complex microvascular remodeling characterized by tortuous, shorter, thicker, highly branched vessels, and overall preserved microvascular density. This remodeling process was reversible in debanding PAB mice in which the RV function recovers over time. The remodeled microvasculature tightly wrapped around the hypertrophied cardiomyocytes to maintain a stable contact surface to cardiomyocytes as an adaptation to RV pressure overload, even in end-stage RV failure. However, microvasculature-cardiomyocyte contact was impaired in areas with interstitial fibrosis where cardiomyocytes displayed signs of hypoxia. Similar to PAB animals, microvascular density in the RV was preserved in patients with end-stage pulmonary arterial hypertension, and microvascular architectural changes appeared to vary by etiology, with patients with pulmonary veno-occlusive disease displaying a lack of microvascular complexity with uniformly short segments. CONCLUSIONS: 3D deep tissue imaging of the failing RV in PAB mice, pulmonary hypertension rats, and patients with pulmonary arterial hypertension reveals complex microvascular changes to preserve the microvascular density and maintain a stable microvascular-cardiomyocyte contact. Our studies provide a novel framework to understand microvascular adaptation in the pressure-overloaded RV that focuses on cell-cell interaction and goes beyond the concept of capillary rarefaction.


Assuntos
Hipertensão Pulmonar , Imageamento Tridimensional , Camundongos Endogâmicos C57BL , Animais , Humanos , Camundongos , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/diagnóstico por imagem , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/patologia , Masculino , Ventrículos do Coração/fisiopatologia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/patologia , Microvasos/fisiopatologia , Microvasos/diagnóstico por imagem , Microvasos/patologia , Remodelação Vascular , Artéria Pulmonar/fisiopatologia , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/patologia , Disfunção Ventricular Direita/fisiopatologia , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/diagnóstico por imagem , Função Ventricular Direita , Remodelação Ventricular , Modelos Animais de Doenças , Miócitos Cardíacos/patologia
5.
Nature ; 586(7831): 785-789, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33057196

RESUMO

In the mammalian lung, an apparently homogenous mesh of capillary vessels surrounds each alveolus, forming the vast respiratory surface across which oxygen transfers to the blood1. Here we use single-cell analysis to elucidate the cell types, development, renewal and evolution of the alveolar capillary endothelium. We show that alveolar capillaries are mosaics; similar to the epithelium that lines the alveolus, the alveolar endothelium is made up of two intermingled cell types, with complex 'Swiss-cheese'-like morphologies and distinct functions. The first cell type, which we term the 'aerocyte', is specialized for gas exchange and the trafficking of leukocytes, and is unique to the lung. The other cell type, termed gCap ('general' capillary), is specialized to regulate vasomotor tone, and functions as a stem/progenitor cell in capillary homeostasis and repair. The two cell types develop from bipotent progenitors, mature gradually and are affected differently in disease and during ageing. This cell-type specialization is conserved between mouse and human lungs but is not found in alligator or turtle lungs, suggesting it arose during the evolution of the mammalian lung. The discovery of cell type specialization in alveolar capillaries transforms our understanding of the structure, function, regulation and maintenance of the air-blood barrier and gas exchange in health, disease and evolution.


Assuntos
Capilares/citologia , Alvéolos Pulmonares/irrigação sanguínea , Alvéolos Pulmonares/citologia , Troca Gasosa Pulmonar , Envelhecimento , Jacarés e Crocodilos/anatomia & histologia , Animais , Evolução Biológica , Capilares/metabolismo , Divisão Celular , Autorrenovação Celular , Senescência Celular , Humanos , Masculino , Camundongos , Alvéolos Pulmonares/metabolismo , Células-Tronco/classificação , Células-Tronco/citologia , Tartarugas/anatomia & histologia
6.
Nature ; 587(7835): 619-625, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33208946

RESUMO

Although single-cell RNA sequencing studies have begun to provide compendia of cell expression profiles1-9, it has been difficult to systematically identify and localize all molecular cell types in individual organs to create a full molecular cell atlas. Here, using droplet- and plate-based single-cell RNA sequencing of approximately 75,000 human cells across all lung tissue compartments and circulating blood, combined with a multi-pronged cell annotation approach, we create an extensive cell atlas of the human lung. We define the gene expression profiles and anatomical locations of 58 cell populations in the human lung, including 41 out of 45 previously known cell types and 14 previously unknown ones. This comprehensive molecular atlas identifies the biochemical functions of lung cells and the transcription factors and markers for making and monitoring them; defines the cell targets of circulating hormones and predicts local signalling interactions and immune cell homing; and identifies cell types that are directly affected by lung disease genes and respiratory viruses. By comparing human and mouse data, we identified 17 molecular cell types that have been gained or lost during lung evolution and others with substantially altered expression profiles, revealing extensive plasticity of cell types and cell-type-specific gene expression during organ evolution including expression switches between cell types. This atlas provides the molecular foundation for investigating how lung cell identities, functions and interactions are achieved in development and tissue engineering and altered in disease and evolution.


Assuntos
Células/classificação , Células/metabolismo , Imunidade , Pulmão/citologia , Análise de Sequência de RNA , Análise de Célula Única , Transcriptoma/genética , Idoso , Animais , Atlas como Assunto , Biomarcadores , Comunicação Celular , Células/imunologia , Quimiocinas/metabolismo , Células Endoteliais/metabolismo , Células Epiteliais/metabolismo , Feminino , Humanos , Pulmão/imunologia , Masculino , Camundongos , Pessoa de Meia-Idade , Receptores de Retorno de Linfócitos/metabolismo , Transdução de Sinais , Células Estromais/metabolismo
7.
Proc Natl Acad Sci U S A ; 120(46): e2301994120, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37903247

RESUMO

The explosive eruption of the Hunga Tonga-Hunga Ha'apai (HTHH) volcano on 15 January 2022 injected more water vapor into the stratosphere and to higher altitudes than ever observed in the satellite era. Here, the evolution of the stratospherically injected water vapor is examined as a function of latitude, altitude, and time in the year following the eruption (February to December 2022), and perturbations to stratospheric chemical composition resulting from the increased sulfate aerosols and water vapor are identified and analyzed. The average calculated mass distribution of elevated water vapor between hemispheres is approximately 78% Southern Hemisphere (SH) and 22% Northern Hemisphere in 2022. Significant changes in stratospheric composition following the HTHH eruption are identified using observations from the Aura Microwave Limb Sounder satellite instrument. The dominant features in the monthly mean vertical profiles averaged over 15° latitude ranges are decreases in O3 (-14%) and HCl (-22%) at SH midlatitudes and increases in ClO (>100%) and HNO3 (43%) in the tropics, with peak pressure-level perturbations listed. Anomalies in column ozone from 1.2-100 hPa due to the HTHH eruption include widespread O3 reductions in SH midlatitudes and O3 increases in the tropics, with peak anomalies in 15° latitude-binned, monthly averages of approximately -7% and +5%, respectively, occurring in austral spring. Using a 3-dimensional chemistry-climate-aerosol model and observational tracer correlations, changes in stratospheric composition are found to be due to both dynamical and chemical factors.

8.
Ann Intern Med ; 177(6): 768-781, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38739921

RESUMO

BACKGROUND: Whether circulating sex hormones modulate mortality and cardiovascular disease (CVD) risk in aging men is controversial. PURPOSE: To clarify associations of sex hormones with these outcomes. DATA SOURCES: Systematic literature review to July 2019, with bridge searches to March 2024. STUDY SELECTION: Prospective cohort studies of community-dwelling men with sex steroids measured using mass spectrometry and at least 5 years of follow-up. DATA EXTRACTION: Independent variables were testosterone, sex hormone-binding globulin (SHBG), luteinizing hormone (LH), dihydrotestosterone (DHT), and estradiol concentrations. Primary outcomes were all-cause mortality, CVD death, and incident CVD events. Covariates included age, body mass index, marital status, alcohol consumption, smoking, physical activity, hypertension, diabetes, creatinine concentration, ratio of total to high-density lipoprotein cholesterol, and lipid medication use. DATA SYNTHESIS: Nine studies provided individual participant data (IPD) (255 830 participant-years). Eleven studies provided summary estimates (n = 24 109). Two-stage random-effects IPD meta-analyses found that men with baseline testosterone concentrations below 7.4 nmol/L (<213 ng/dL), LH concentrations above 10 IU/L, or estradiol concentrations below 5.1 pmol/L had higher all-cause mortality, and those with testosterone concentrations below 5.3 nmol/L (<153 ng/dL) had higher CVD mortality risk. Lower SHBG concentration was associated with lower all-cause mortality (median for quintile 1 [Q1] vs. Q5, 20.6 vs. 68.3 nmol/L; adjusted hazard ratio [HR], 0.85 [95% CI, 0.77 to 0.95]) and lower CVD mortality (adjusted HR, 0.81 [CI, 0.65 to 1.00]). Men with lower baseline DHT concentrations had higher risk for all-cause mortality (median for Q1 vs. Q5, 0.69 vs. 2.45 nmol/L; adjusted HR, 1.19 [CI, 1.08 to 1.30]) and CVD mortality (adjusted HR, 1.29 [CI, 1.03 to 1.61]), and risk also increased with DHT concentrations above 2.45 nmol/L. Men with DHT concentrations below 0.59 nmol/L had increased risk for incident CVD events. LIMITATIONS: Observational study design, heterogeneity among studies, and imputation of missing data. CONCLUSION: Men with low testosterone, high LH, or very low estradiol concentrations had increased all-cause mortality. SHBG concentration was positively associated and DHT concentration was nonlinearly associated with all-cause and CVD mortality. PRIMARY FUNDING SOURCE: Medical Research Future Fund, Government of Western Australia, and Lawley Pharmaceuticals. (PROSPERO: CRD42019139668).


Assuntos
Doenças Cardiovasculares , Causas de Morte , Di-Hidrotestosterona , Estradiol , Hormônio Luteinizante , Globulina de Ligação a Hormônio Sexual , Testosterona , Humanos , Masculino , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/sangue , Testosterona/sangue , Globulina de Ligação a Hormônio Sexual/análise , Globulina de Ligação a Hormônio Sexual/metabolismo , Estradiol/sangue , Hormônio Luteinizante/sangue , Di-Hidrotestosterona/sangue , Incidência , Fatores de Risco , Idoso , Pessoa de Meia-Idade
9.
Front Neuroendocrinol ; 70: 101080, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37268277

RESUMO

Low vitamin D status is linked with poorer cognition in adults while findings in relation to high levels are mixed.We performed a systematic review and meta-analyses to examine dose-response associations between 25-hydroxyvitamin D (25OHD) levelsand cognitive performance in community-dwelling adults. Thirty-eight observational studies were included in dose-response meta-analyses. Positive, nonlinear associations were identified between baseline25OHD levels and global cognition incross-sectional and longitudinal analyses, and for performance in memory and executive function in longitudinal analyses. When restricted to studies involving older adults, thepattern emerged forspecific domains in cross-sectional analyses. Poorer performance was associated with low 25OHD levels, while a sharp improvement was associated withlevels up to 60-70 nM/L. Further improvement was observed only for longitudinal global cognition. Our findings support the association between low vitamin D and poorer cognition and suggest levels of at least 60 nM/L are associated with better cognition during ageing.


Assuntos
Vida Independente , Vitamina D , Estudos Transversais , Cognição , Função Executiva
10.
Clin Exp Immunol ; 216(3): 293-306, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38430552

RESUMO

Sepsis is characterized by a dysfunctional host response to infection culminating in life-threatening organ failure that requires complex patient management and rapid intervention. Timely diagnosis of the underlying cause of sepsis is crucial, and identifying those at risk of complications and death is imperative for triaging treatment and resource allocation. Here, we explored the potential of explainable machine learning models to predict mortality and causative pathogen in sepsis patients. By using a modelling pipeline employing multiple feature selection algorithms, we demonstrate the feasibility of identifying integrative patterns from clinical parameters, plasma biomarkers, and extensive phenotyping of blood immune cells. While no single variable had sufficient predictive power, models that combined five and more features showed a macro area under the curve (AUC) of 0.85 to predict 90-day mortality after sepsis diagnosis, and a macro AUC of 0.86 to discriminate between Gram-positive and Gram-negative bacterial infections. Parameters associated with the cellular immune response contributed the most to models predictive of 90-day mortality, most notably, the proportion of T cells among PBMCs, together with expression of CXCR3 by CD4+ T cells and CD25 by mucosal-associated invariant T (MAIT) cells. Frequencies of Vδ2+ γδ T cells had the most profound impact on the prediction of Gram-negative infections, alongside other T-cell-related variables and total neutrophil count. Overall, our findings highlight the added value of measuring the proportion and activation patterns of conventional and unconventional T cells in the blood of sepsis patients in combination with other immunological, biochemical, and clinical parameters.


Assuntos
Sepse , Humanos , Sepse/imunologia , Sepse/microbiologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Biomarcadores/sangue , Receptores CXCR3/metabolismo , Aprendizado de Máquina , Subunidade alfa de Receptor de Interleucina-2/sangue , Subunidade alfa de Receptor de Interleucina-2/imunologia , Imunidade Celular , Linfócitos T CD4-Positivos/imunologia , Linfócitos T/imunologia , Prognóstico , Infecções por Bactérias Gram-Negativas/imunologia
11.
Bioinformatics ; 39(1)2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36413065

RESUMO

MOTIVATION: Clustering is an unsupervised method for identifying structure in unlabelled data. In the context of cytometry, it is typically used to categorize cells into subpopulations of similar phenotypes. However, clustering is greatly dependent on hyperparameters and the data to which it is applied as each algorithm makes different assumptions and generates a different 'view' of the dataset. As such, the choice of clustering algorithm can significantly influence results, and there is often not one preferred method but different insights to be obtained from different methods. To overcome these limitations, consensus approaches are needed that directly address the effect of competing algorithms. To the best of our knowledge, consensus clustering algorithms designed specifically for the analysis of cytometry data are lacking. RESULTS: We present a novel ensemble clustering methodology based on geometric median clustering with weighted voting (GeoWaVe). Compared to graph ensemble clustering methods that have gained popularity in single-cell RNA sequencing analysis, GeoWaVe performed favourably on different sets of high-dimensional mass and flow cytometry data. Our findings provide proof of concept for the power of consensus methods to make the analysis, visualization and interpretation of cytometry data more robust and reproducible. The wide availability of ensemble clustering methods is likely to have a profound impact on our understanding of cellular responses, clinical conditions and therapeutic and diagnostic options. AVAILABILITY AND IMPLEMENTATION: GeoWaVe is available as part of the CytoCluster package https://github.com/burtonrj/CytoCluster and published on the Python Package Index https://pypi.org/project/cytocluster. Benchmarking data described are available from https://doi.org/10.5281/zenodo.7134723. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Algoritmos , Política , Análise por Conglomerados , Citometria de Fluxo/métodos , Sequenciamento do Exoma
12.
Hum Reprod ; 39(3): 509-515, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38265302

RESUMO

STUDY QUESTION: Can women with pregnancy of unknown location (PUL) following in vitro fertilization (IVF) be risk-stratified regarding the subsequent need for medical intervention, based on their demographic characteristics and the results of serum biochemistry at the initial visit? SUMMARY ANSWER: The ratio of serum hCG to number of days from conception (hCG/C) or the initial serum hCG level at ≥5 weeks' gestation could be used to estimate the risk of women presenting with PUL following IVF and needing medical intervention during their follow-up. WHAT IS KNOWN ALREADY: In women with uncertain conception dates presenting with PUL, a single serum hCG measurement cannot be used to predict the final pregnancy outcomes, thus, serial levels are mandatory to establish a correct diagnosis. Serum progesterone levels can help to risk-stratify women at their initial visit but are not accurate in those taking progesterone supplementation, such as women pregnant following IVF. STUDY DESIGN, SIZE, DURATION: This was a retrospective study carried out at two specialist early pregnancy assessment units between May 2008 and January 2021. A total of 224 women met the criteria for inclusion, but 14 women did not complete the follow-up and were excluded from the study. PARTICIPANTS/MATERIALS, SETTING, METHODS: We selected women who had an IVF pregnancy and presented with PUL at ≥5 weeks' gestation. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 30/210 (14.0%, 95% CI 9.9-19.8) women initially diagnosed with PUL required surgical intervention. The hCG/C was significantly higher in the group of women requiring an intervention compared to those who did not (P = 0.003), with an odds ratio of 3.65 (95% CI 1.49-8.89, P = 0.004). A hCG/C <4.0 was associated with a 1.9% risk of intervention, which accounted for 25.7% of the study population. A similar result was obtained by substituting hCG/C <4.0 with an initial hCG level <100 IU/l, which was associated with 2.0% risk of intervention, and accounted for 23.8% of the study population (P > 0.05). LIMITATIONS, REASONS FOR CAUTION: A limitation of our study is that it is retrospective in nature, and as such, we were reliant on existing data. WIDER IMPLICATIONS OF THE FINDINGS: A previous study in women with PUL after spontaneous conception found that a 2% intervention rate was considered low enough to eliminate the need for close follow-up and serial blood tests. Using the same 2% cut-off, a quarter of women with PUL after IVF could also avoid attending for further visits and investigations. STUDY FUNDING/COMPETING INTEREST(S): No external funding was required for this study. No conflicts of interest are required to be declared. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Fertilização in vitro , Progesterona , Gravidez , Feminino , Humanos , Estudos Retrospectivos , Fertilização in vitro/efeitos adversos , Fertilização in vitro/métodos , Resultado da Gravidez , Gravidez de Alto Risco
13.
J Clin Psychopharmacol ; 44(2): 86-88, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38230858

RESUMO

BACKGROUND: Rapid cycling (RC) at least 4 recurrent episodes per year in bipolar disorder (BD) has been recognized since the 1970s. We now comment on our recent review of the topic and extensive RC analysis in a large clinical cohort, emphasizing therapeutics research. COMMENTS: Prevalence of RC-BD averages 36% for any year versus 22% in the preceding year. Rapid cycling is not a consistent feature over many years, although average long-term, annual recurrence rates are greater in RC-BD patients. Risk of RC may be somewhat greater among women and with older ages. It is also associated with cyclothymic temperament, prominent depression, and mood-switching with antidepressant treatment and is associated with increased suicidal risk. Treatment of individual episodes in RC-BD and effective long-term prevention remain inadequately studied, although antidepressant treatment can worsen RC. Some research supports treatment with aripiprazole, lamotrigine, and lithium, and interest in second-generation antipsychotics is emerging. All such options are used in various inadequately evaluated combinations. CONCLUSIONS: Rapid cycling is prevalent among BD patients but seems to vary in risk over time without evidence of progressive worsening. Treatment of acute episodes in RC-BD patients and effective long-term preventive management require much more intensive investigation.


Assuntos
Antipsicóticos , Transtorno Bipolar , Humanos , Feminino , Transtorno Bipolar/epidemiologia , Antipsicóticos/efeitos adversos , Antidepressivos/uso terapêutico , Lítio/uso terapêutico , Anticonvulsivantes/uso terapêutico
14.
J Clin Psychopharmacol ; 44(2): 117-123, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38230861

RESUMO

BACKGROUND: As clinical practices with lithium salts for patients diagnosed with bipolar disorder (BD) are poorly documented in Asia, we studied the prevalence and clinical correlates of lithium use there to support international comparisons. METHODS: We conducted a cross-sectional study of use and dosing of lithium salts for BD patients across 13 Asian sites and evaluated bivariate relationships of lithium treatment with clinical correlates followed by multivariate logistic regression modeling. RESULTS: In a total of 2139 BD participants (52.3% women) of mean age 42.4 years, lithium salts were prescribed in 27.3% of cases overall, varying among regions from 3.20% to 59.5%. Associated with lithium treatment were male sex, presence of euthymia or mild depression, and a history of seasonal mood change. Other mood stabilizers usually were given with lithium, often at relatively high doses. Lithium use was associated with newly emerging and dose-dependent risk of tremors as well as risk of hypothyroidism. We found no significant differences in rates of clinical remission or of suicidal behavior if treatment included lithium or not. CONCLUSIONS: Study findings clarify current prevalence, dosing, and clinical correlates of lithium treatment for BD in Asia. This information should support clinical decision-making regarding treatment of BD patients and international comparisons of therapeutic practices.


Assuntos
Transtorno Bipolar , Humanos , Masculino , Feminino , Adulto , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/epidemiologia , Transtorno Bipolar/induzido quimicamente , Lítio/uso terapêutico , Estudos Transversais , Farmacoepidemiologia , Sais/uso terapêutico , Antimaníacos/uso terapêutico , Compostos de Lítio/uso terapêutico
15.
Curr Opin Crit Care ; 30(4): 324-332, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38841918

RESUMO

PURPOSE OF REVIEW: We review the current Society for Cardiovascular Angiography and Interventions (SCAI) cardiogenic shock classification system and consider alternatives or iterations that may enhance our current descriptions of cardiogenic shock trajectory. RECENT FINDINGS: Several studies have identified the potential prognostic value of serial SCAI stage re-assessment, usually within the first 24 h of shock onset, to predict deterioration and clinical outcomes across shock causes. In parallel, numerous registry-based analyses support the utility of a more precise assessment of the macrocirculation and microcirculation, leveraging invasive haemodynamics, imaging and additional laboratory and clinical markers. The emergence of machine learning and artificial intelligence capabilities offers the opportunity to integrate multimodal data into high fidelity, real-time metrics to more precisely define trajectory and inform our therapeutic decision making. SUMMARY: Whilst the SCAI staging system remains a pivotal tool in cardiogenic shock assessment, communication and reassessment, it is vital that the sophistication with which we measure and assess shock trajectory evolves in parallel our understanding of the complexity and variability of clinical course and clinical outcomes.


Assuntos
Choque Cardiogênico , Humanos , Choque Cardiogênico/fisiopatologia , Choque Cardiogênico/diagnóstico por imagem , Prognóstico , Hemodinâmica/fisiologia , Sociedades Médicas
16.
Acta Psychiatr Scand ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38922810

RESUMO

BACKGROUND: Anticipating diagnostic change from major depressive (MDD) to bipolar disorder (BD) can support better prognosis and treatment, especially of depression but is challenging and reported research results are inconsistent. We therefore assessed clinical characteristics associated with diagnostic change from MDD to BD with antidepressant treatments. METHODS: We compared characteristics of 3212 initially MDD patients who became (hypo)manic during antidepressant treatment to those with stable MDD diagnoses as well as with cases of stable, spontaneous BD, using standard bivariate and multivariate statistics. RESULTS: Among MDD patients, 6.69% [CI: 5.85-7.61] changed to BD, mostly type II (BD2, 76.7%). BD-converters had higher rates of familial mood disorders (74.1% vs. 57.1%) or BD (33.7% vs. 21.0%) and 2.8-years younger onset than stable MDD patients. They also had more prior depressive recurrences/year, years-of-illness, mood-stabilizer treatment, divorces, fewer children, more suicide attempts and drug-abuse, and higher intake cyclothymia, YMRS and MDQ scores. Predictors independently associated with diagnostic conversion were: more familial BD, depressions/year, unemployment, cyclothymic temperament, suicidal ideation or acts, and fewer children. BD-converters vs. spontaneous BD cases had significantly more suicide attempts, BD2 diagnoses, and affected relatives. Converting to vs. spontaneous BD1 was associated with more ADHD, more suicidal ideation or behavior, MDI course, and younger onset; converting to vs. spontaneous BD2 had more episodes/year, unemployment, ADHD, substance abuse, suicidal ideation or attempts, and more relatives with BD. CONCLUSIONS: Few (6.69%) initially MDD subjects converted to BD, most (76.7%) to BD2. Independent predictive associations with diagnostic change included: familial BD, more depressions/year, unemployment, cyclothymic temperament, suicidal behavior and fewer children. Notably, several characteristics were stronger among those changing to BD during antidepressant treatment vs. others with spontaneous BD.

17.
Br J Anaesth ; 132(5): 1073-1081, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38448267

RESUMO

BACKGROUND: Regional anaesthesia plays an important role in perioperative care, but gaps in proficiency persist among consultants and specialists. This study aimed to assess confidence levels in performing Plan A blocks among this cohort and to examine the barriers and facilitators influencing regional anaesthesia education. METHODS: Utilising a mixed-methods design, we performed a quantitative survey to gauge self-reported confidence in performing Plan A blocks, coupled with qualitative interviews to explore the complexities of educational barriers and facilitators. UK consultant and specialist anaesthetists were included in the study. RESULTS: A total of 369 survey responses were analysed. Only 22% of survey respondents expressed confidence in performing all Plan A blocks. Specialists (odds ratio [OR] 0.391, 95% confidence interval [CI] 0.179-0.855, P=0.016) and those in their roles for >10 yr (OR 0.551, 95% CI 0.327-0.927, P = 0.024) reported lower confidence levels. A purposive sample was selected for interviews, and data saturation was reached at 31 interviews. Peer-led learning emerged as the most effective learning modality for consultants and specialists. Barriers to regional anaesthesia education included apprehensions regarding complications, self-perceived incompetence, lack of continuing professional development time, insufficient support from the multidisciplinary team, and a lack of inclusivity within the regional anaesthesia community. Organisational culture had a substantial impact, with the presence of local regional anaesthesia champions emerging as a key facilitator. CONCLUSIONS: This study highlights persistent perceived deficiencies in regional anaesthesia skills among consultants and specialists. We identified multiple barriers and facilitators, providing insights for targeted interventions aimed at improving regional anaesthesia education in this group.


Assuntos
Anestesia por Condução , Anestesiologia , Humanos , Consultores , Anestesia Local , Anestesiologia/educação , Reino Unido
18.
Artigo em Espanhol | MEDLINE | ID: mdl-38874349

RESUMO

We describe two cases of secondary prevention subcutaneous implantable cardioverter defibrillator (S-ICD) implantation and subsequent S-ICD electrode displacement which initially went undetected. One presentation was a result of a coincidental chest x-ray for respiratory exacerbation and another with an untreated episode highlighted via remote monitoring, both patients were booked to clinic for further investigation. Our findings highlighted had there been a comparison of the existing subcutaneous electrogram (S-ECG) to captured S-ECGs at time of implant the electrode displacement would have been detected beforehand. This underpins the importance of introducing the simple management strategy into routine follow-up.

19.
Clin Radiol ; 79(5): 338-345, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38360516

RESUMO

The implementation of artificial intelligence (AI) applications in routine practice, following regulatory approval, is currently limited by practical concerns around reliability, accountability, trust, safety, and governance, in addition to factors such as cost-effectiveness and institutional information technology support. When a technology is new and relatively untested in a field, professional confidence is lacking and there is a sense of the need to go above the baseline level of validation and compliance. In this article, we propose an approach that goes beyond standard regulatory compliance for AI apps that are approved for marketing, including independent benchmarking in the lab as well as clinical audit in practice, with the aims of increasing trust and preventing harm.


Assuntos
Inteligência Artificial , Radiologia , Humanos , Reprodutibilidade dos Testes , Radiografia
20.
Proc Natl Acad Sci U S A ; 118(11)2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33729988

RESUMO

Understanding magnetic-field generation and amplification in turbulent plasma is essential to account for observations of magnetic fields in the universe. A theoretical framework attributing the origin and sustainment of these fields to the so-called fluctuation dynamo was recently validated by experiments on laser facilities in low-magnetic-Prandtl-number plasmas ([Formula: see text]). However, the same framework proposes that the fluctuation dynamo should operate differently when [Formula: see text], the regime relevant to many astrophysical environments such as the intracluster medium of galaxy clusters. This paper reports an experiment that creates a laboratory [Formula: see text] plasma dynamo. We provide a time-resolved characterization of the plasma's evolution, measuring temperatures, densities, flow velocities, and magnetic fields, which allows us to explore various stages of the fluctuation dynamo's operation on seed magnetic fields generated by the action of the Biermann-battery mechanism during the initial drive-laser target interaction. The magnetic energy in structures with characteristic scales close to the driving scale of the stochastic motions is found to increase by almost three orders of magnitude and saturate dynamically. It is shown that the initial growth of these fields occurs at a much greater rate than the turnover rate of the driving-scale stochastic motions. Our results point to the possibility that plasma turbulence produced by strong shear can generate fields more efficiently at the driving scale than anticipated by idealized magnetohydrodynamics (MHD) simulations of the nonhelical fluctuation dynamo; this finding could help explain the large-scale fields inferred from observations of astrophysical systems.

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