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1.
Nature ; 630(8017): 671-676, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38867039

RESUMEN

The subpectoral diverticulum (SPD) is an extension of the respiratory system in birds that is located between the primary muscles responsible for flapping the wing1,2. Here we survey the pulmonary apparatus in 68 avian species, and show that the SPD was present in virtually all of the soaring taxa investigated but absent in non-soarers. We find that this structure evolved independently with soaring flight at least seven times, which indicates that the diverticulum might have a functional and adaptive relationship with this flight style. Using the soaring hawks Buteo jamaicensis and Buteo swainsoni as models, we show that the SPD is not integral for ventilation, that an inflated SPD can increase the moment arm of cranial parts of the pectoralis, and that pectoralis muscle fascicles are significantly shorter in soaring hawks than in non-soaring birds. This coupling of an SPD-mediated increase in pectoralis leverage with force-specialized muscle architecture produces a pneumatic system that is adapted for the isometric contractile conditions expected in soaring flight. The discovery of a mechanical role for the respiratory system in avian locomotion underscores the functional complexity and heterogeneity of this organ system, and suggests that pulmonary diverticula are likely to have other undiscovered secondary functions. These data provide a mechanistic explanation for the repeated appearance of the SPD in soaring lineages and show that the respiratory system can be co-opted to provide biomechanical solutions to the challenges of flight and thereby influence the evolution of avian volancy.


Asunto(s)
Vuelo Animal , Animales , Vuelo Animal/fisiología , Músculos Pectorales/fisiología , Alas de Animales/fisiología , Alas de Animales/anatomía & histología , Pulmón/fisiología , Aves/fisiología , Halcones/fisiología , Sistema Respiratorio/anatomía & histología , Fenómenos Biomecánicos , Evolución Biológica , Modelos Biológicos
2.
Nature ; 626(7997): 169-176, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38267577

RESUMEN

To coordinate cellular physiology, eukaryotic cells rely on the rapid exchange of molecules at specialized organelle-organelle contact sites1,2. Endoplasmic reticulum-mitochondrial contact sites (ERMCSs) are particularly vital communication hubs, playing key roles in the exchange of signalling molecules, lipids and metabolites3,4. ERMCSs are maintained by interactions between complementary tethering molecules on the surface of each organelle5,6. However, due to the extreme sensitivity of these membrane interfaces to experimental perturbation7,8, a clear understanding of their nanoscale organization and regulation is still lacking. Here we combine three-dimensional electron microscopy with high-speed molecular tracking of a model organelle tether, Vesicle-associated membrane protein (VAMP)-associated protein B (VAPB), to map the structure and diffusion landscape of ERMCSs. We uncovered dynamic subdomains within VAPB contact sites that correlate with ER membrane curvature and undergo rapid remodelling. We show that VAPB molecules enter and leave ERMCSs within seconds, despite the contact site itself remaining stable over much longer time scales. This metastability allows ERMCSs to remodel with changes in the physiological environment to accommodate metabolic needs of the cell. An amyotrophic lateral sclerosis-associated mutation in VAPB perturbs these subdomains, likely impairing their remodelling capacity and resulting in impaired interorganelle communication. These results establish high-speed single-molecule imaging as a new tool for mapping the structure of contact site interfaces and reveal that the diffusion landscape of VAPB at contact sites is a crucial component of ERMCS homeostasis.


Asunto(s)
Retículo Endoplásmico , Mitocondrias , Membranas Mitocondriales , Movimiento , Proteínas de Transporte Vesicular , Humanos , Esclerosis Amiotrófica Lateral/genética , Retículo Endoplásmico/química , Retículo Endoplásmico/metabolismo , Retículo Endoplásmico/ultraestructura , Mitocondrias/química , Mitocondrias/metabolismo , Mitocondrias/ultraestructura , Membranas Mitocondriales/química , Membranas Mitocondriales/metabolismo , Membranas Mitocondriales/ultraestructura , Transducción de Señal , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo , Proteínas de Transporte Vesicular/ultraestructura , Microscopía Electrónica , Imagenología Tridimensional , Sitios de Unión , Difusión , Factores de Tiempo , Mutación , Homeostasis
3.
Nature ; 591(7851): 659-664, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33658713

RESUMEN

Symmetric cell division requires the even partitioning of genetic information and cytoplasmic contents between daughter cells. Whereas the mechanisms coordinating the segregation of the genome are well known, the processes that ensure organelle segregation between daughter cells remain less well understood1. Here we identify multiple actin assemblies with distinct but complementary roles in mitochondrial organization and inheritance in mitosis. First, we find a dense meshwork of subcortical actin cables assembled throughout the mitotic cytoplasm. This network scaffolds the endoplasmic reticulum and organizes three-dimensional mitochondrial positioning to ensure the equal segregation of mitochondrial mass at cytokinesis. Second, we identify a dynamic wave of actin filaments reversibly assembling on the surface of mitochondria during mitosis. Mitochondria sampled by this wave are enveloped within actin clouds that can spontaneously break symmetry to form elongated comet tails. Mitochondrial comet tails promote randomly directed bursts of movement that shuffle mitochondrial position within the mother cell to randomize inheritance of healthy and damaged mitochondria between daughter cells. Thus, parallel mechanisms mediated by the actin cytoskeleton ensure both equal and random inheritance of mitochondria in symmetrically dividing cells.


Asunto(s)
Actinas/química , Actinas/metabolismo , Mitocondrias/metabolismo , Mitosis , Citoesqueleto de Actina/química , Citoesqueleto de Actina/metabolismo , Animales , División Celular , Línea Celular , Citocinesis , Retículo Endoplásmico/metabolismo , Hipocampo/citología , Hipocampo/embriología , Humanos , Mitocondrias/química , Neuronas , Ratas
4.
Proc Natl Acad Sci U S A ; 121(23): e2308531121, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38805288

RESUMEN

Many animals exhibit remarkable colors that are produced by the constructive interference of light reflected from arrays of intracellular guanine crystals. These animals can fine-tune their crystal-based structural colors to communicate with each other, regulate body temperature, and create camouflage. While it is known that these changes in color are caused by changes in the angle of the crystal arrays relative to incident light, the cellular machinery that drives color change is not understood. Here, using a combination of 3D focused ion beam scanning electron microscopy (FIB-SEM), micro-focused X-ray diffraction, superresolution fluorescence light microscopy, and pharmacological perturbations, we characterized the dynamics and 3D cellular reorganization of crystal arrays within zebrafish iridophores during norepinephrine (NE)-induced color change. We found that color change results from a coordinated 20° tilting of the intracellular crystals, which alters both crystal packing and the angle at which impinging light hits the crystals. Importantly, addition of the dynein inhibitor dynapyrazole-a completely blocked this NE-induced red shift by hindering crystal dynamics upon NE addition. FIB-SEM and microtubule organizing center (MTOC) mapping showed that microtubules arise from two MTOCs located near the poles of the iridophore and run parallel to, and in between, individual crystals. This suggests that dynein drives crystal angle change in response to NE by binding to the limiting membrane surrounding individual crystals and walking toward microtubule minus ends. Finally, we found that intracellular cAMP regulates the color change process. Together, our results provide mechanistic insight into the cellular machinery that drives structural color change.


Asunto(s)
Pez Cebra , Animales , Norepinefrina/metabolismo , Norepinefrina/farmacología , Color , Pigmentación/fisiología , Microscopía Electrónica de Rastreo , Proteínas de Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/química
5.
Artículo en Inglés | MEDLINE | ID: mdl-38913573

RESUMEN

Rationale: Idiopathic pulmonary fibrosis (IPF) causes irreversible fibrosis of the lung parenchyma. While antifibrotic therapy can slow IPF progression, treatment response is variable. There exists a critical need to develop a precision medicine approach to IPF. Objective: To identify and validate biologically driven molecular endotypes of IPF. Methods: Latent class analysis (LCA) was independently performed in prospectively recruited discovery (n=875) and validation (n=347) cohorts. Twenty-five plasma biomarkers associated with fibrogenesis served as class-defining variables. The association between molecular endotype and 4-year transplant-free survival was tested using multivariable Cox regression adjusted for baseline confounders. Endotype-dependent differential treatment response to future antifibrotic exposure was then assessed in a pooled cohort of patients naïve to antifibrotic therapy at time of biomarker measurement (n=555). Results: LCA independently identified two latent classes in both cohorts (p<0.0001). WAP four-disulfide core domain protein 2 (WFDC2) was the most important determinant of class membership across cohorts. Membership in Class 2 was characterized by higher biomarker concentrations and higher risk of death or transplantation (discovery: HR 2.02 [95% CI 1.64-2.48]; p<0.001; validation: HR 1.95 [1.34-2.82]; p<0.001). In pooled analysis, significant heterogeneity in treatment effect was observed between endotypes (pinteraction=0.030), with a favorable antifibrotic response in Class 2 (HR 0.64 [0.45-0.93]; p=0.018) but not in Class 1 (HR 1.19 [0.77-1.84]; p=0.422). Conclusions: In this multicohort study, we identified two novel molecular endotypes of IPF with divergent clinical outcomes and response to antifibrotics. Pending further validation, these endotypes could enable a precision medicine approach for future IPF clinical trials.

6.
Pediatr Blood Cancer ; 71(4): e30889, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38265260

RESUMEN

BACKGROUND: An international expert panel recently recommended 15 'non-stage prognostic indicators' (NSPIs) across eight childhood cancers, classified as essential or additional, for collection in population-based cancer registries. We aimed to describe the incidence distribution and survival of each of these NSPIs. PROCEDURES: Cases were extracted from the Australian Childhood Cancer Registry. The study cohort (n = 4187) comprised all children aged under 15 years diagnosed with an eligible cancer between 2010 and 2018, with follow-up until 31 December 2020. NSPI data were collected directly from each patient's medical records. Differences in 5-year relative survival were assessed using multivariable flexible parametric models, adjusted for sex and age group at diagnosis. RESULTS: The availability of data varied, exceeding 85% for all essential NSPIs apart from histologic subtype for Wilms tumours (69%) and lineage for acute lymphoblastic leukaemia (78%). Information on additional NSPIs tended to be recorded less often, particularly cytogenetic subtype for non-alveolar rhabdomyosarcoma (28%) and astrocytoma (4%). Eight NSPIs exhibited a significant difference in survival, with the largest disparity occurring among children with astrocytoma according to tumour grade (5-year relative survival of 18% for grade IV disease compared with 99% for grade I disease; p < .001). CONCLUSIONS: Our findings demonstrate that most of the recommended NSPIs can be retrieved from medical records in Australia in recent years, allowing the capability of assessing survival within patient subgroups of clinical interest. Reporting of NSPI data has the capability to inform local and global understanding of population-level disparities in childhood cancer survival.


Asunto(s)
Astrocitoma , Neoplasias Renales , Neoplasias , Niño , Humanos , Lactante , Neoplasias/epidemiología , Neoplasias/terapia , Incidencia , Pronóstico , Australia/epidemiología , Sistema de Registros
7.
Pediatr Blood Cancer ; 71(7): e31031, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38679843

RESUMEN

Invasive fungal disease (IFD) occurs less frequently during treatment for solid compared to hematological malignancies in children, and risk groups are poorly defined. Retrospective national multicenter cohort data (2004-2013) were analyzed to document prevalence, clinical characteristics, and microbiology of IFD. Amongst 2067 children treated for solid malignancy, IFD prevalence was 1.9% overall and 1.4% for proven/probable IFD. Of all IFD episodes, 42.5% occurred in patients with neuroblastoma (prevalence 7.0%). Candida species comprised 54.8% of implicated pathogens in proven/probable IFD. In children with solid tumors, IFD is rare, and predominantly caused by yeasts.Routine prophylaxis may not be warranted.


Asunto(s)
Infecciones Fúngicas Invasoras , Neoplasias , Humanos , Niño , Masculino , Femenino , Neoplasias/microbiología , Neoplasias/epidemiología , Estudios Retrospectivos , Preescolar , Australia/epidemiología , Lactante , Adolescente , Infecciones Fúngicas Invasoras/epidemiología , Infecciones Fúngicas Invasoras/etiología , Infecciones Fúngicas Invasoras/prevención & control , Prevalencia , Recién Nacido
8.
Nature ; 562(7727): 373-379, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30209392

RESUMEN

Mixed phenotype acute leukaemia (MPAL) is a high-risk subtype of leukaemia with myeloid and lymphoid features, limited genetic characterization, and a lack of consensus regarding appropriate therapy. Here we show that the two principal subtypes of MPAL, T/myeloid (T/M) and B/myeloid (B/M), are genetically distinct. Rearrangement of ZNF384 is common in B/M MPAL, and biallelic WT1 alterations are common in T/M MPAL, which shares genomic features with early T-cell precursor acute lymphoblastic leukaemia. We show that the intratumoral immunophenotypic heterogeneity characteristic of MPAL is independent of somatic genetic variation, that founding lesions arise in primitive haematopoietic progenitors, and that individual phenotypic subpopulations can reconstitute the immunophenotypic diversity in vivo. These findings indicate that the cell of origin and founding lesions, rather than an accumulation of distinct genomic alterations, prime tumour cells for lineage promiscuity. Moreover, these findings position MPAL in the spectrum of immature leukaemias and provide a genetically informed framework for future clinical trials of potential treatments for MPAL.


Asunto(s)
Leucemia Bifenotípica Aguda/genética , Leucemia Bifenotípica Aguda/patología , Linaje de la Célula/genética , Análisis Mutacional de ADN , Femenino , Variación Genética/genética , Genoma Humano/genética , Genómica , Humanos , Inmunofenotipificación , Leucemia Bifenotípica Aguda/clasificación , Masculino , Modelos Genéticos , Mutación/genética , Células Madre Neoplásicas/inmunología , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Fenotipo , Transactivadores/genética
9.
Psychol Res ; 88(3): 826-836, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38200373

RESUMEN

Subjective perception of time is altered during vigorous exercise. This could be due in part to the fatigue associated with physical activity at high intensities. The aim of this study was to determine the effect of fatigue, specifically, on subjective time perception. Twenty-six healthy, untrained subjects (17 men/9 women; age = 26.0 ± 4.3 years; V ˙ O 2 peak = 38.13 ± 5.62 mL/kg/min) completed a maximal aerobic exercise test on a cycle ergometer. Time perception was assessed before (PRE) and after (POST) the exercise test using a time production task wherein subjects started a stopwatch and stopped it once they believed a designated time period had passed. This time produced with the stopwatch was the estimate of the target time that was compared to the target time interval. Relative error of the timing task was significantly higher for POST (0.112 ± 0.260) than for PRE (0.028 ± 0.173), p = .032, η2 = .178. Subjects produced ~ 8.4% more time than the target intervals when fatigued, which is indicative of a slower sense of time perception. A shift in attentional focus from timing to the sensations associated with fatigue is a possible factor to explain this result. Future studies which investigate the effects of exercise on time perception should consider the impact of fatigue experienced during exercise.


Asunto(s)
Ejercicio Físico , Percepción del Tiempo , Masculino , Humanos , Femenino , Adulto Joven , Adulto , Prueba de Esfuerzo , Fatiga
10.
Nat Methods ; 17(9): 917-921, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32778832

RESUMEN

The actin cytoskeleton plays multiple critical roles in cells, from cell migration to organelle dynamics. The small and transient actin structures regulating organelle dynamics are challenging to detect with fluorescence microscopy, making it difficult to determine whether actin filaments are directly associated with specific membranes. To address these limitations, we developed fluorescent-protein-tagged actin nanobodies, termed 'actin chromobodies' (ACs), targeted to organelle membranes to enable high-resolution imaging of sub-organellar actin dynamics.


Asunto(s)
Citoesqueleto de Actina/fisiología , Imagen Óptica/métodos , Línea Celular , Citoesqueleto , Recuperación de Fluorescencia tras Fotoblanqueo , Técnica del Anticuerpo Fluorescente , Humanos , Proteínas Luminiscentes , Proteína Fluorescente Roja
11.
Crit Care Med ; 51(12): e269-e274, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37695136

RESUMEN

OBJECTIVES: Interleukin-18 (IL-18) plasma level and latent class analysis (LCA) have separately been shown to predict prognosis and treatment response in acute respiratory distress syndrome (ARDS). IL-18 is a measure of inflammasome activation, a pathway potentially distinct from inflammation captured by biomarkers defining previously published LCA classes. We hypothesized that elevated IL-18 would identify distinct "high-risk" patients not captured by prior LCA classifications. DESIGN: Statins for acutely injured lungs from sepsis (SAILS) and hydroxymethylglutaryl-CoA reductase inhibition with simvastatin in acute lung injury to reduce pulmonary dysfunction trial (HARP-2) are two large randomized, controlled trials in ARDS in which both LCA assignments and IL-18 levels were shown to predict mortality. We first evaluated the overlap between high IL-18 levels (≥ 800 pg/mL) with prior LCA class assignments using McNemar's test and then tested the correlation between IL-18 and LCA biomarkers using Pearson's exact test on log-2 transformed values. Our primary analysis was the association of IL-18 level with 60-day mortality in the hypoinflammatory LCA class, which was assessed using the Fisher exact test and Cox proportional hazards modeling adjusting for age, Acute Physiology and Chronic Health Evaluation score, and gender. Secondary analyses included the association of IL-18 and LCA with mortality within each IL-18/LCA subgroup. SETTING: Secondary analysis of two multicenter, randomized controlled clinical trials of ARDS patients. SUBJECTS: Six hundred eighty-three patients in SAILS and 511 patients in HARP-2. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We found that 33% of patients in SAILS and HARP-2 were discordant by IL-18 level and LCA class. We further found that IL-18 level was only modestly correlated (0.17-0.47) with cytokines used in the LCA assignment. A substantial subset of individuals classified as hypoinflammatory by LCA (14% of SAILS and 43% of HARP-2) were classified as high risk by elevated IL-18. These individuals were at high risk for mortality in both SAILS (42% 60-d mortality, odds ratio [OR] 3.3; 95% CI, 1.8-6.1; p < 0.001) and HARP-2 (27% 60-d mortality, OR 2.1; 95% CI, 1.2-3.8; p = 0.009). CONCLUSIONS: Plasma IL-18 level provides important additional prognostic information to LCA subphenotypes defined largely by traditional inflammatory biomarkers in two large ARDS cohorts.


Asunto(s)
Interleucina-18 , Síndrome de Dificultad Respiratoria , Humanos , Análisis de Clases Latentes , Estudios Retrospectivos , Citocinas , Ensayos Clínicos Controlados Aleatorios como Asunto , Síndrome de Dificultad Respiratoria/terapia , Biomarcadores , Interleucina-8
12.
Blood ; 137(26): 3629-3640, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-33619528

RESUMEN

The expression of ZAP-70 in a subset of chronic lymphocytic leukemia (CLL) patients strongly correlates with a more aggressive clinical course, although the exact underlying mechanisms remain elusive. The ability of ZAP-70 to enhance B-cell receptor (BCR) signaling, independently of its kinase function, is considered to contribute. We used RNA-sequencing and proteomic analyses of primary cells differing only in their expression of ZAP-70 to further define how ZAP-70 increases the aggressiveness of CLL. We identified that ZAP-70 is directly required for cell survival in the absence of an overt BCR signal, which can compensate for ZAP-70 deficiency as an antiapoptotic signal. In addition, the expression of ZAP-70 regulates the transcription of factors regulating the recruitment and activation of T cells, such as CCL3, CCL4, and IL4I1. Quantitative mass spectrometry of double-cross-linked ZAP-70 complexes further demonstrated constitutive and direct protein-protein interactions between ZAP-70 and BCR-signaling components. Unexpectedly, ZAP-70 also binds to ribosomal proteins, which is not dependent on, but is further increased by, BCR stimulation. Importantly, decreased expression of ZAP-70 significantly reduced MYC expression and global protein synthesis, providing evidence that ZAP-70 contributes to translational dysregulation in CLL. In conclusion, ZAP-70 constitutively promotes cell survival, microenvironment interactions, and protein synthesis in CLL cells, likely to improve cellular fitness and to further drive disease progression.


Asunto(s)
Regulación Leucémica de la Expresión Génica , Leucemia Linfocítica Crónica de Células B/metabolismo , Proteínas de Neoplasias/metabolismo , Biosíntesis de Proteínas , Proteína Tirosina Quinasa ZAP-70/metabolismo , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/genética , Masculino , Proteínas de Neoplasias/genética , Células Tumorales Cultivadas , Proteína Tirosina Quinasa ZAP-70/genética
13.
Paediatr Perinat Epidemiol ; 37(1): 81-91, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35672573

RESUMEN

BACKGROUND: Large improvements in childhood cancer survival have been reported over recent decades. Data from cancer registries have the advantage of providing a 'whole of population' approach to gauge the success of cancer control efforts. OBJECTIVES: The aim of this study was to investigate recent survival estimates for children diagnosed with cancer Australia and to examine the extent of changes in survival over the last 35 years. For the first time, we also estimated the number of deaths among Australian children that were potentially avoided due to improvements in survival. METHODS: A retrospective, population-based cohort study design was used. Case information was extracted from the Australian Childhood Cancer Registry for 1983-2016, with follow-up to 31 December 2017. Eligible children were aged 0-14 with a basis of diagnosis other than autopsy or death certificate only. Five-year relative survival was calculated using the semi-complete cohort method for three diagnosis periods (1983-1994, 1995-2006 and 2007-2016), and changes in survival over time were assessed via flexible parametric models. Avoided deaths within 5 years for those diagnosed between 1995 and 2016 were estimated under the assumption that survival rates remained the same as for 1983-1994. RESULTS: Overall 5-year survival within the study cohort (n = 20,871) increased from 72.8% between 1983 and1994 to 86.1% between 2007 and 2016, equating to an adjusted excess mortality hazard ratio of 1.82 (95% confidence interval 1.67, 1.97). Most cancers showed improvements in survival; other gliomas, hepatoblastoma and osteosarcoma were exceptions. Among children diagnosed between 1995 and 2016, 38.7% of expected deaths within 5 years of diagnosis (n = 1537 of 3970) were avoided due to temporal improvements in survival. CONCLUSIONS: Survival for childhood cancer has continued to improve over recent years, thanks mainly to ongoing progress in treatment development combined with improved supportive care. Providing innovative measures of survival, such as avoided deaths, may assist with understanding outcome data produced by cancer registries.


Asunto(s)
Neoplasias Hepáticas , Neoplasias , Niño , Humanos , Estudios de Cohortes , Estudios Retrospectivos , Australia/epidemiología , Tasa de Supervivencia , Sistema de Registros
14.
Acta Oncol ; 62(10): 1256-1264, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37647245

RESUMEN

BACKGROUND: The Toronto Paediatric Cancer Stage Guidelines are a compendium of staging systems developed to facilitate collection of consistent and comparable data on stage at diagnosis for childhood cancers by cancer registries. MATERIAL AND METHODS: This retrospective, observational cohort study investigated changes in stage-specific incidence and survival for children diagnosed between 2000-2008 compared to 2009-2017 using the population-based Australian Childhood Cancer Registry. Information on mortality for each patient was available to 31st December 2020. Shifts in incidence by stage were evaluated using chi-square tests, and differences in stage-specific five-year observed survival for all causes of death over time were assessed using flexible parametric models. RESULTS: Stage was assigned according to the Toronto Guidelines for 96% (n = 7944) of the total study cohort (n = 8292). Changes in the distribution of incidence by stage between the two diagnosis periods were observed for retinoblastoma, with stage 0 increasing from 26% to 37% of cases (p = 0.02), and hepatoblastoma, with metastatic disease increasing from 22% to 39% of cases (p = 0.04). There were large gains in stage-specific survival over time for stage IV rhabdomyosarcoma (five-year adjusted mortality hazard ratio for 2009-2017 compared to 2000-2008 of 0.38, 95% CI 0.19-0.77; p = 0.01), stage M3 for medulloblastoma (HR = 0.41, 95% CI 0.21-0.79; p = 0.01) and metastatic neuroblastoma excluding stage MS (HR = 0.61, 95% CI 0.44-0.84; p < 0.01). CONCLUSION: These results indicate that improvements in childhood cancer survival in Australia are most likely due to refined management rather than changes in stage at diagnosis, particularly for metastatic solid tumours. Wide international uptake of the Toronto Guidelines will allow comprehensive evaluation of differences in survival between countries.


Asunto(s)
Neoplasias Primarias Secundarias , Neoplasias , Neuroblastoma , Niño , Humanos , Neoplasias/epidemiología , Incidencia , Estudios Retrospectivos , Australia/epidemiología , Estadificación de Neoplasias , Sistema de Registros , Neoplasias Primarias Secundarias/patología
15.
Crit Care ; 27(1): 126, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36978134

RESUMEN

BACKGROUND: Two acute respiratory distress syndrome (ARDS) trials showed no benefit for statin therapy, though secondary analyses suggest inflammatory subphenotypes may have a differential response to simvastatin. Statin medications decrease cholesterol levels, and low cholesterol has been associated with increased mortality in critical illness. We hypothesized that patients with ARDS and sepsis with low cholesterol could be harmed by statins. METHODS: Secondary analysis of patients with ARDS and sepsis from two multicenter trials. We measured total cholesterol from frozen plasma samples obtained at enrollment in Statins for Acutely Injured Lungs from Sepsis (SAILS) and Simvastatin in the Acute Respiratory Distress Syndrome (HARP-2) trials, which randomized subjects with ARDS to rosuvastatin versus placebo and simvastatin versus placebo, respectively, for up to 28 days. We compared the lowest cholesterol quartile (< 69 mg/dL in SAILS, < 44 mg/dL in HARP-2) versus all other quartiles for association with 60-day mortality and medication effect. Fisher's exact test, logistic regression, and Cox Proportional Hazards were used to assess mortality. RESULTS: There were 678 subjects with cholesterol measured in SAILS and 509 subjects in HARP-2, of whom 384 had sepsis. Median cholesterol at enrollment was 97 mg/dL in both SAILS and HARP-2. Low cholesterol was associated with higher APACHE III and shock prevalence in SAILS, and higher Sequential Organ Failure Assessment score and vasopressor use in HARP-2. Importantly, the effect of statins differed in these trials. In SAILS, patients with low cholesterol who received rosuvastatin were more likely to die (odds ratio (OR) 2.23, 95% confidence interval (95% CI) 1.06-4.77, p = 0.02; interaction p = 0.02). In contrast, in HARP-2, low cholesterol patients had lower mortality if randomized to simvastatin, though this did not reach statistical significance in the smaller cohort (OR 0.44, 95% CI 0.17-1.07, p = 0.06; interaction p = 0.22). CONCLUSIONS: Cholesterol levels are low in two cohorts with sepsis-related ARDS, and those in the lowest cholesterol quartile are sicker. Despite the very low levels of cholesterol, simvastatin therapy seems safe and may reduce mortality in this group, though rosuvastatin was associated with harm.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas , Síndrome de Dificultad Respiratoria , Sepsis , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Rosuvastatina Cálcica/farmacología , Rosuvastatina Cálcica/uso terapéutico , Simvastatina/farmacología , Simvastatina/uso terapéutico , Síndrome de Dificultad Respiratoria/terapia , Sepsis/complicaciones
16.
Br J Anaesth ; 130(3): 287-295, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36369016

RESUMEN

The randomised controlled trial is the foundation of clinical research; yet there is concern that many trials have flaws in design, conduct, and reporting that undermine trustworthiness. Common flaws in trials include high risk of bias, small size, outcomes irrelevant to clinical care and patient's experience, and inability to detect efficacy even if present. These flaws carry forward into systematic reviews, which can confer the label of 'high-quality evidence' on inadequate data. Trials can be futile because their flaws mean that they cannot deliver any meaningful result in that different results in a small number of patients would be sufficient to change conclusions. Some trials have been discovered to be fabricated, the number of which is growing. The fields of anaesthesia and pain have more fabricated trials than other clinical fields, possibly because of increased vigilance. This narrative review examines these themes in depth whilst acknowledging an inescapable conclusion: that much of our clinical evidence is in trouble, and special measures are needed to bolster quality and confidence.


Asunto(s)
Anestesia , Humanos , Dolor Postoperatorio
17.
Health Care Manag Sci ; 26(1): 79-92, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36282367

RESUMEN

We analyze the progression of COVID-19 in the United States over a nearly one-year period beginning March 1, 2020 with a novel metric motivated by queueing models, tracking partial-average day-of-event and cumulative probability distributions for events, where events are points in time when new cases and new deaths are reported. The partial average represents the average day of all events preceding a point of time, and is an indicator as to whether the pandemic is accelerating or decelerating in the context of the entire history of the pandemic. The measure supplements traditional metrics, and also enables direct comparisons of case and death histories on a common scale. We also compare methods for estimating actual infections and deaths to assess the timing and dynamics of the pandemic by location. Three example states are graphically compared as functions of date, as well as Hong Kong as an example that experienced a pronounced recent wave of the pandemic. In addition, statistics are compared for all 50 states. Over the period studied, average case day and average death day varied by two to five months among the 50 states, depending on data source, with the earliest averages in New York and surrounding states, as well as Louisiana.


Asunto(s)
COVID-19 , Humanos , Estados Unidos/epidemiología , Pandemias , Benchmarking , Hong Kong
18.
BMC Musculoskelet Disord ; 24(1): 91, 2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36732742

RESUMEN

BACKGROUND: Revision total knee replacement (TKR) is a major operation with a long recovery period and many patients report suboptimal outcomes. Rehabilitation has the potential to improve outcomes. The aim of this study was to understand current provision of rehabilitation for revision TKR in England and evaluate the existing evidence. METHODS: Phase 1: An online national survey of education and rehabilitation provision for patients receiving revision TKR was completed by physiotherapy staff at 22 hospitals across England that were high volume for revision TKR (response rate of 34%). Phase 2: Systematic review to identify studies evaluating rehabilitation programmes for revision joint replacement. Searches were conducted in MEDLINE, EMBASE, PsycINFO, CINAHL, and Cochrane databases from inception to 15th June 2022. Randomised controlled trials (RCTs) and observational studies that evaluated post-operative rehabilitation for adults undergoing revision joint replacement were included. Screening, data extraction and quality assessment was undertaken by two reviewers. RESULTS: Phase 1: Pre-operative education which aimed to prepare patients for surgery and recovery was provided in most hospitals, predominately involving a single session delivered by a multidisciplinary team. Inpatient physiotherapy commonly commenced on post-operative day 1 and was provided twice daily, with most hospitals also providing occupational therapy. Rehabilitation was often provided in the first four weeks after hospital discharge, either in an outpatient, community or home setting. In most hospitals, the education and rehabilitation provided to patients receiving revision TKR was the same as that provided to patients undergoing primary TKR. Phase 2: Of the 1,445 articles identified, three retrospective cohort studies based on hospital records review were included. The studies evaluated intensive inpatient rehabilitation programmes, consisting of 2-3 h of daily group or individual physiotherapy, with additional occupational therapy in one study. All three studies reported improvement in functional outcomes for patients undergoing rehabilitation after revision TKR. All studies were limited by their retrospective design, short duration of follow-up and lack of sample size calculation. No RCTs evaluating effectiveness of rehabilitation for revision TKR were identified. CONCLUSION: This study identified the need for future research to develop and evaluate tailored rehabilitation to optimise patient outcomes following revision TKR.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Adulto , Humanos , Artroplastia de Reemplazo de Rodilla/rehabilitación , Inglaterra , Modalidades de Fisioterapia
19.
BMC Musculoskelet Disord ; 24(1): 972, 2023 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-38102656

RESUMEN

BACKGROUND: The Support and Treatment After Replacement (STAR) care pathway is a clinically important and cost-effective intervention found to improve pain outcomes over one year for people with chronic pain three months after total knee replacement (TKR). We followed up STAR trial participants to evaluate the longer-term clinical- and cost-effectiveness of this care pathway. METHODS: Participants who remained enrolled on the trial at one year were contacted by post at a median of four years after randomisation and invited to complete a questionnaire comprising the same outcomes collected during the trial. We captured pain (co-primary outcome using the Brief Pain Inventory (BPI) pain severity and interference scales; scored 0-10, best to worst), function, neuropathic characteristics, emotional aspects of pain, health-related quality of life, and satisfaction. Electronic hospital informatics data on hospital resource use for the period of one to four years post-randomisation were collected from participating hospital sites. The economic evaluation took an National Health Service (NHS) secondary care perspective, with a four-year time horizon. RESULTS: Overall, 226/337 (67%) of participants returned completed follow-up questionnaires, yielding adjusted between-group differences in BPI means of -0.42 (95% confidence interval, CI (-1.07, 0.23); p = 0.20) for pain severity and - 0.64 (95% CI -1.41, 0.12); p = 0.10) for pain interference. Analysis using a multiple imputed data set (n = 337) showed an incremental net monetary benefit in favour of the STAR care pathway of £3,525 (95% CI -£990 to £8,039) at a £20,000/QALY willingness-to-pay threshold, leading to a probability that the intervention was cost-effective of 0.94. CONCLUSIONS: The magnitude of the longer-term benefits of the STAR care pathway are uncertain due to attrition of trial participants; however, there is a suggestion of some degree of sustained clinical benefit at four years. The care pathway remained cost-effective at four years. TRIAL REGISTRATION: ISRCTN: 92,545,361.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Dolor Crónico , Humanos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Resultado del Tratamiento , Vías Clínicas , Estudios de Seguimiento , Dolor Crónico/diagnóstico , Dolor Crónico/etiología , Dolor Crónico/cirugía , Calidad de Vida , Medicina Estatal , Análisis Costo-Beneficio , Años de Vida Ajustados por Calidad de Vida
20.
J Med Internet Res ; 25: e42551, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-37405845

RESUMEN

BACKGROUND: Osteoarthritis is a leading cause of pain and disability. Knee osteoarthritis accounts for nearly four-fifths of the burden of osteoarthritis internationally, and 10% of adults in the United Kingdom have the condition. Shared decision-making (SDM) supports patients to make more informed choices about treatment and care while reducing inequities in access to treatment. We evaluated the experience of a team adapting an SDM tool for knee osteoarthritis and the tool's implementation potential within a local clinical commissioning group (CCG) area in southwest England. The tool aims to prepare patients and clinicians for SDM by providing evidence-based information about treatment options relevant to disease stage. OBJECTIVE: This study aimed to explore the experiences of a team adapting an SDM tool from one health context to another and the implementation potential of the tool in the local CCG area. METHODS: A partnership approach using mixed methods was used to respond to recruitment challenges and ensure that study aims could be addressed within time restrictions. A web-based survey was used to obtain clinicians' feedback on experiences of using the SDM tool. Qualitative interviews were conducted by telephone or video call with a sample of stakeholders involved in adapting and implementing the tool in the local CCG area. Survey findings were summarized as frequencies and percentages. Content analysis was conducted on qualitative data using framework analysis, and data were mapped directly to the Theoretical Domains Framework (TDF). RESULTS: Overall, 23 clinicians completed the survey, including first-contact physiotherapists (11/23, 48%), physiotherapists (7/23, 30%), specialist physiotherapists (4/23, 17%), and a general practitioner (1/23, 4%). Eight stakeholders involved in commissioning, adapting, and implementing the SDM tool were interviewed. Participants described barriers and facilitators to the adaptation, implementation, and use of the tool. Barriers included a lack of organizational culture that supported and resourced SDM, lack of clinician buy-in and awareness of the tool, challenges with accessibility and usability, and lack of adaptation for underserved communities. Facilitators included the influence of clinical leaders' belief that SDM tools can improve patient outcomes and National Health Service resource use, clinicians' positive experiences of using the tool, and improving awareness of the tool. Themes were mapped to 13 of the 14 TDF domains. Usability issues were described, which did not map to the TDF domains. CONCLUSIONS: This study highlights barriers and facilitators to adapting and implementing tools from one health context to another. We recommend that tools selected for adaptation should have a strong evidence base, including evidence of effectiveness and acceptability in the original context. Legal advice should be sought regarding intellectual property early in the project. Existing guidance for developing and adapting interventions should be used. Co-design methods should be applied to improve adapted tools' accessibility and acceptability.


Asunto(s)
Toma de Decisiones Conjunta , Salud Única , Osteoartritis de la Rodilla , Participación del Paciente , Adulto , Humanos , Toma de Decisiones , Inglaterra , Osteoartritis de la Rodilla/terapia , Participación del Paciente/métodos , Medicina Estatal
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