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BACKGROUND: Hepatocellular carcinoma (HCC) incidence has increased rapidly, and prognosis remains poor. We aimed to explore predictors of routes to diagnosis (RtD), and outcomes, in HCC cases. METHODS: HCC cases diagnosed 2006-2017 were identified from the National Cancer Registration Dataset and linked to Hospital Episode Statistics and the RtD metric. Multivariable logistic regression was used to explore associations between RtD, diagnosis year, 365-day mortality and receipt of potentially curative treatment. RESULTS: 23,555 HCC cases were identified; 36.1% via emergency presentation (EP), 30.2% GP referral (GP), 17.1% outpatient referral, 11.0% two-week wait and 4.6% other/unknown routes. Odds of 365-day mortality was >70% lower via GP or OP routes than EP, and odds of curative treatment 3-4 times higher. Further adjustment for cancer/cirrhosis stage attenuated the associations with curative treatment. People who were older, female, had alcohol-related liver disease, or were more deprived, were at increased risk of an EP. Over time, diagnoses via EP decreased, and via GP increased. CONCLUSIONS: HCC RtD is an important predictor of outcomes. Continuing to reduce EP and increase GP and OP presentations, for example by identifying and regularly monitoring patients at higher risk of HCC, may improve stage at diagnosis and survival.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/epidemiología , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/epidemiología , Femenino , Masculino , Anciano , Persona de Mediana Edad , Adulto , Derivación y Consulta/estadística & datos numéricos , Pronóstico , Anciano de 80 o más Años , Adulto Joven , AdolescenteRESUMEN
BACKGROUND: This study presents minimum 6-year follow-up data on the survival and satisfaction of an uncemented modular revision femoral system, following on from our previously published earlier results. METHODS: We retrospectively reviewed all revision hip arthroplasties performed at our institution between January 2005 and October 2012, using a single modular femoral revision system. Patient-reported outcomes were collected (satisfaction score and Oxford Hip Score). Preoperative and postoperative radiographs were reviewed for stem subsidence, and Kaplan-Meier analysis was performed for survival. A total of 115 femoral revisions were performed in 106 patients. RESULTS: All-cause survival was 82% (95% confidence interval 74 to 91%) at 10.8 years, and 96% (95% confidence interval 90 to 100%) excluding septic failure. Of the 19 cases requiring reoperation, 16 were for infection, 2 for aseptic loosening, and 1 for mechanical failure. At final follow-up, 88.5% of patients were "satisfied" or "very satisfied". CONCLUSIONS: This study showed excellent clinical results of a commonly used revision hip stem with at least 10 years follow-up. Satisfaction rates were high, with few aseptic failures. Stem subsidence was more common in revisions for infection, but did not correlate with lower satisfaction scores.
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Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Humanos , Artroplastia de Reemplazo de Cadera/efectos adversos , Reoperación/métodos , Estudios Retrospectivos , Diseño de Prótesis , Falla de Prótesis , Resultado del Tratamiento , Estudios de SeguimientoRESUMEN
Many countries curate national registries of liver transplant (LT) data. These registries are often used to generate predictive models; however, potential performance and transferability of these models remain unclear. We used data from 3 national registries and developed machine learning algorithm (MLA)-based models to predict 90-day post-LT mortality within and across countries. Predictive performance and external validity of each model were assessed. Prospectively collected data of adult patients (aged ≥18 years) who underwent primary LTs between January 2008 and December 2018 from the Canadian Organ Replacement Registry (Canada), National Health Service Blood and Transplantation (United Kingdom), and United Network for Organ Sharing (United States) were used to develop MLA models to predict 90-day post-LT mortality. Models were developed using each registry individually (based on variables inherent to the individual databases) and using all 3 registries combined (variables in common between the registries [harmonized]). The model performance was evaluated using area under the receiver operating characteristic (AUROC) curve. The number of patients included was as follows: Canada, n = 1214; the United Kingdom, n = 5287; and the United States, n = 59,558. The best performing MLA-based model was ridge regression across both individual registries and harmonized data sets. Model performance diminished from individualized to the harmonized registries, especially in Canada (individualized ridge: AUROC, 0.74; range, 0.73-0.74; harmonized: AUROC, 0.68; range, 0.50-0.73) and US (individualized ridge: AUROC, 0.71; range, 0.70-0.71; harmonized: AUROC, 0.66; range, 0.66-0.66) data sets. External model performance across countries was poor overall. MLA-based models yield a fair discriminatory potential when used within individual databases. However, the external validity of these models is poor when applied across countries. Standardization of registry-based variables could facilitate the added value of MLA-based models in informing decision making in future LTs.
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Trasplante de Hígado , Adulto , Humanos , Adolescente , Medicina Estatal , Canadá/epidemiología , Aprendizaje Automático , Sistema de Registros , Estudios RetrospectivosRESUMEN
BACKGROUND AND AIMS: Identifying international differences in utilization and outcomes of liver transplantation (LT) after donation after circulatory death (DCD) donation provides a unique opportunity for benchmarking and population-level insight. METHODS: Adult (≥18 years) LT data between 2008 and 2018 from the UK and US were used to assess mortality and graft failure after DCD LT. We used time-dependent Cox-regression methods to estimate hazard ratios (HR) for risk-adjusted short-term (0-90 days) and longer-term (90 days-5 years) outcomes. RESULTS: One-thousand five-hundred-and-sixty LT receipts from the UK and 3426 from the US were included. Over the study period, the use of DCD livers increased from 15.7% to 23.9% in the UK compared to 5.1% to 7.6% in the US. In the UK, DCD donors were older (UK:51 vs. US:33 years) with longer cold ischaemia time (UK: 437 vs. US: 333 min). Recipients in the US had higher Model for End-stage Liver Disease (MELD) scores, higher body mass index, higher proportions of ascites, encephalopathy, diabetes and previous abdominal surgeries. No difference in the risk-adjusted short-term mortality or graft failure was observed between the countries. In the longer-term (90 days-5 years), the UK had lower mortality and graft failure (adj.mortality HR:UK: 0.63 (95% CI: 0.49-0.80); graft failure HR: UK: 0.72, 95% CI: 0.58-0.91). The cumulative incidence of retransplantation was higher in the UK (5 years: UK: 11.9% vs. 4.6%; p < .001). CONCLUSIONS: For those receiving a DCD LT, longer-term post-transplant outcomes in the UK are superior to the US, however, significant differences in recipient illness, graft quality and access to retransplantation were seen between the two countries.
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Enfermedad Hepática en Estado Terminal , Trasplante de Hígado , Obtención de Tejidos y Órganos , Adulto , Humanos , Enfermedad Hepática en Estado Terminal/cirugía , Índice de Severidad de la Enfermedad , Donantes de Tejidos , Reino Unido/epidemiología , Estudios Retrospectivos , Supervivencia de Injerto , Muerte EncefálicaRESUMEN
The authors report a penetrating orbitocerebral vape pen injury necessitating a primary enucleation and craniotomy to remove the foreign body fragments. A 31-year-old male presented with acute right vision loss after a modifiable vape pen explosion launched multiple projectile fragments into his right eye. CT revealed a deformed globe with multiple radiodense curvilinear fragments in the superior orbital roof and intracranial space. A right frontal craniotomy and orbitotomy with removal of vape pen fragments, reconstruction of the orbital roof, primary enucleation, and eyelid repair were performed in conjunction with neurosurgery. To the best of the authors' knowledge, this is the first reported penetrating globe injury from a vape pen explosion.
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Lesiones Oculares , Cuerpos Extraños , Fracturas Orbitales , Vapeo , Masculino , Humanos , Adulto , Órbita/diagnóstico por imagen , Órbita/cirugía , Órbita/lesiones , Fracturas Orbitales/diagnóstico , Fracturas Orbitales/etiología , Fracturas Orbitales/cirugíaRESUMEN
OBJECTIVE: NovoSorb (Poly-Novo Ltd, Australia) biodegradable temporising matrix (BTM) is a novel artificial dermal matrix. Previous literature is weighted towards its use in burns reconstruction; however, this paper describes its use within a range of wound aetiologies. The authors present one of the largest and most diverse case series to date, and aim to provide an independent benchmark of clinical practice. METHOD: A retrospective observational study was performed. Patient demographics and clinical data (wound aetiology, site, total body surface area (TBSA), wound bed, number of debridements, time to BTM integration, time to skin grafting) were collected and subgroup analysis preformed. RESULTS: The cohort consisted of 37 patients (acute trauma wounds, n=19; hard-to-heal wounds, n=9; acute infections, n=6; cancer, n=3). Successful BTM integration, allowing subsequent split-thickness skin grafting (STSG), occurred in 70% of cases, despite an overall complication rate of 51%. Mean time from BTM application to STSG was 53 days. There was no difference in STSG outcomes when grafting was performed either before or after the six-week BTM application period. There was no difference when various wound beds (fascia, tendon, periosteum) were compared. Patients >65 years of age were more likely to experience complications; however, this did not affect the speed of integration. The relation of diabetes and smoking to overall integration had no statistical significance. CONCLUSION: In comorbid patients in particular, the time between BTM application and STSG may be longer than the manufacturer's recommendation. Furthermore, data suggest greater wound bed optimisation and closer interval monitoring in hard-to-heal/malignant wounds, and in older patients and patients with comorbidities. However, BTM appears robust (even in infection) and is showing promise as a useful reconstructive tool.
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Piel , Cicatrización de Heridas , Humanos , Anciano , Piel/lesiones , Trasplante de Piel , Poliuretanos , Estudios Observacionales como AsuntoRESUMEN
BACKGROUND: Non-alcoholic steatohepatitis (NASH)-associated hepatocellular carcinoma (HCC) is a rising indication for liver transplantation. This unique population, with multiple comorbidities, has potential for worse post-transplant outcomes. We compared post-transplant survival of NASH and non-NASH HCC patients using a large cohort. METHODS: Adults transplanted for HCC between 2008 and 2018, from United Network for Organ Sharing (UNOS) and University Health Network (UHN) databases were divided into two populations: NASH and non-NASH. Recipient characteristics and post-transplant survival were compared. Subgroup analyses were performed within and beyond Milan criteria. RESULTS: 2071 of 20,672 (10.0%) patients underwent transplantation for NASH HCC, with annual proportional increase of 1.2%UHN (p = 0.02) and 1.3%UNOS (p < 0.001). The 1-,3-,5-year post-transplant survival were 90.8%, 83.9%, 76.3% NASH HCC versus 91.9%, 82.1%, 74.9% non-NASH HCC (p = 0.94). No survival differences were observed in populations within or beyond Milan. Competing-risk analysis demonstrated no differences in risk for cardiovascular-related death (HR1.24, 95%CI 0.87-1.55, p = 0.16), or HCC recurrence-related death (HR1.21, 95%CI 0.89-1.65, p = 0.23). NASH HCC patients had lower risk of liver-related deaths (HR0.57, 95%CI 0.34-0.98, p = 0.04). DISCUSSION: NASH HCC is a rising indication for liver transplantation. Despite demographic differences, no post-transplantation survival differences were observed between NASH and non-NASH HCC. This justifies equivalent organ allocation, irrespective of NASH status.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Trasplante de Hígado , Enfermedad del Hígado Graso no Alcohólico , Adulto , Humanos , Trasplante de Hígado/efectos adversos , Resultado del Tratamiento , Estudios Retrospectivos , Enfermedad del Hígado Graso no Alcohólico/cirugíaRESUMEN
BACKGROUND & AIMS: Adult-to-adult living donor liver transplantation (LDLT) offers an opportunity to decrease the liver transplant waitlist and reduce waitlist mortality. We sought to compare donor and recipient characteristics and post-transplant outcomes after LDLT in the US, the UK, and Canada. METHODS: This is a retrospective multicenter cohort-study of adults (≥18-years) who underwent primary LDLT between Jan-2008 and Dec-2018 from three national liver transplantation registries: United Network for Organ Sharing (US), National Health Service Blood and Transplantation (UK), and the Canadian Organ Replacement Registry (Canada). Patients undergoing retransplantation or multi-organ transplantation were excluded. Post-transplant survival was evaluated using the Kaplan-Meier method, and multivariable adjustments were performed using Cox proportional-hazards models with mixed-effect modeling. RESULTS: A total of 2,954 living donor liver transplants were performed (US: n = 2,328; Canada: n = 529; UK: n = 97). Canada has maintained the highest proportion of LDLT utilization over time (proportion of LDLT in 2008 - US: 3.3%; Canada: 19.5%; UK: 1.7%; p <0.001 - in 2018 - US: 5.0%; Canada: 13.6%; UK: 0.4%; p <0.001). The 1-, 5-, and 10-year patient survival was 92.6%, 82.8%, and 70.0% in the US vs. 96.1%, 89.9%, and 82.2% in Canada vs. 91.4%, 85.4%, and 66.7% in the UK. After adjustment for characteristics of donors, recipients, transplant year, and treating transplant center as a random effect, all countries had a non-statistically significantly different mortality hazard post-LDLT (Ref US: Canada hazard ratio 0.53, 95% CI 0.28-1.01, p = 0.05; UK hazard ratio 1.09, 95% CI 0.59-2.02, p = 0.78). CONCLUSIONS: The use of LDLT has remained low in the US, the UK and Canada. Despite this, long-term survival is excellent. Continued efforts to increase LDLT utilization in these countries may be warranted due to the growing waitlist and differences in allocation that may disadvantage patients currently awaiting liver transplantation. LAY SUMMARY: This multicenter international comparative analysis of living donor liver transplantation in the United States, the United Kingdom, and Canada demonstrates that despite low use of the procedure, the long-term outcomes are excellent. In addition, the mortality risk is not statistically significantly different between the evaluated countries. However, the incidence and risk of retransplantation differs between the countries, being the highest in the United Kingdom and lowest in the United States.
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Trasplante de Hígado , Donadores Vivos , Humanos , Adulto , Estados Unidos/epidemiología , Trasplante de Hígado/métodos , Medicina Estatal , Estudios Retrospectivos , Canadá/epidemiologíaRESUMEN
PURPOSE: Low-dose and very low-dose intravitreal bevacizumab (IVB) have been reported to be successful in short-term treatment of type 1 retinopathy of prematurity (ROP), down to an initial dose of 0.004 mg. We now report 12-month outcomes for these infants. DESIGN: Masked, multicenter, dose de-escalation study. PARTICIPANTS: One hundred twenty prematurely born infants with type 1 ROP. METHODS: A cohort of 120 infants with type 1 ROP in at least 1 eye from 2 sequential dose de-escalation studies of low-dose IVB (0.25 mg, 0.125 mg, 0.063 mg, and 0.031 mg) or very low-dose IVB (0.016 mg, 0.008 mg, 0.004 mg, and 0.002 mg) to the study eye; the fellow eye (if also type 1) received 1 dose level higher of IVB. After primary success or failure at 4 weeks, clinical management was at investigator discretion, including all additional treatment. MAIN OUTCOME MEASURES: Reactivation of severe ROP by 6 months corrected age, additional treatments, retinal and other ocular structural outcomes, and refractive error at 12 months corrected age. RESULTS: Sixty-two of 113 study eyes (55%) and 55 of 98 fellow eyes (56%) received additional treatment. Of the study eyes, 31 (27%) received additional ROP treatment, and 31 (27%) received prophylactic laser therapy for persistent avascular retina. No trend toward a higher risk of additional ROP treatment related to initial IVB doses was found. However, time to reactivation among study eyes was shorter in eyes that received very low-dose IVB (mean, 76.4 days) than in those that received low-dose IVB (mean, 85.7 days). At 12 months, poor retinal outcomes and anterior segment abnormalities both were uncommon (3% and 5%, respectively), optic atrophy was noted in 10%, median refraction was mildly myopic (-0.31 diopter), and strabismus was present in 29% of infants. CONCLUSIONS: Retinal structural outcomes were very good after low- and very low-dose IVB as initial treatment for type 1 ROP, although many eyes received additional treatment. The rate of reactivation of severe ROP was not associated with dose; however, a post hoc data-driven analysis suggested that reactivation was sooner with very low doses.
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Retinopatía de la Prematuridad , Inhibidores de la Angiogénesis/uso terapéutico , Bevacizumab/uso terapéutico , Edad Gestacional , Humanos , Lactante , Recién Nacido , Inyecciones Intravítreas , Coagulación con Láser , Retinopatía de la Prematuridad/diagnóstico , Retinopatía de la Prematuridad/tratamiento farmacológico , Retinopatía de la Prematuridad/cirugía , Estudios RetrospectivosRESUMEN
We present a method for rapid calculation of coronavirus growth rates and [Formula: see text]-numbers tailored to publicly available UK data. We assume that the case data comprise a smooth, underlying trend which is differentiable, plus systematic errors and a non-differentiable noise term, and use bespoke data processing to remove systematic errors and noise. The approach is designed to prioritize up-to-date estimates. Our method is validated against published consensus [Formula: see text]-numbers from the UK government and is shown to produce comparable results two weeks earlier. The case-driven approach is combined with weight-shift-scale methods to monitor trends in the epidemic and for medium-term predictions. Using case-fatality ratios, we create a narrative for trends in the UK epidemic: increased infectiousness of the B1.117 (Alpha) variant, and the effectiveness of vaccination in reducing severity of infection. For longer-term future scenarios, we base future [Formula: see text] on insight from localized spread models, which show [Formula: see text] going asymptotically to 1 after a transient, regardless of how large the [Formula: see text] transient is. This accords with short-lived peaks observed in case data. These cannot be explained by a well-mixed model and are suggestive of spread on a localized network. This article is part of the theme issue 'Technical challenges of modelling real-life epidemics and examples of overcoming these'.
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Coronavirus , Epidemias , Epidemias/prevención & control , Reproducción , Reino Unido/epidemiologíaRESUMEN
Pancreatic ductal adenocarcinoma (PDAC) is one of the most fatal and aggressive malignancies with a 5-year survival rate less than 9%. Early detection is particularly difficult due to the lack of symptoms even in advanced stages. microRNAs (miRs/miRNAs) are small (~ 18-24 nucleotides), endogenous, non-coding RNAs, which are involved in the pathogenesis of several malignancies including PDAC. Alterations of miR expressions can lead to apoptosis, angiogenesis, and metastasis. The role of environmental pollutants such as cadmium (Cd) in PDAC has been suggested but not fully understood. This study underlines the role of miRs (miR-221, miR-155, miR-126) in response to cadmium chloride (CdCl2) in vitro. Lethal concentration (LC50) values for CdCl2 resulted in a toxicity series of AsPC-1 > HPNE > BxPC-3 > Panc-1 = Panc-10.5. Following the treatment with CdCl2, miR-221 and miR-155 were significantly overexpressed, whereas miR-126 was downregulated. An increase in epithelial-mesenchymal transition (EMT) via the dysregulation of mesenchymal markers such as Wnt-11, E-cadherin, Snail, and Zeb1 was also observed. Hence, this study has provided evidence to suggest that the environmental pollutant Cd can have a significant role in the development of PDAC, suggesting a significant correlation between miRs and Cd exposure during PDAC progression. Further studies are needed to investigate the precise role of miRs in PDAC progression as well as the role of Cd and other environmental pollutants.
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Cloruro de Cadmio/toxicidad , Carcinoma Ductal Pancreático/patología , MicroARNs/genética , Neoplasias Pancreáticas/patología , Carcinoma Ductal Pancreático/genética , Línea Celular Tumoral , Progresión de la Enfermedad , Contaminantes Ambientales/toxicidad , Transición Epitelial-Mesenquimal/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pancreáticas/genéticaRESUMEN
BACKGROUND: To our knowledge, no analysis of data from liver transplantation registries exists in Canada. We aimed to describe temporal trends in the number of liver transplantation procedures, patient characteristics and posttransplantation outcomes for autoimmune liver diseases (AILDs) in Canada. METHODS: We used administrative data from the Canadian Organ Replacement Register, which contains liver transplantation information from 6 centres in Canada. This study included transplantation information from 5 of the centres, as liver transplantation procedures in children were not included. We included adult (age ≥ 18 yr) patients with a diagnosis of primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), autoimmune hepatitis (AIH) or overlap syndrome (PBC-AIH or PSC-AIH) who received a liver transplant from 2000 to 2018. RESULTS: Of 5722 primary liver transplantation procedures performed over the study period, 1070 (18.7%) were for an AILD: 489 (45.7%) for PSC, 341 (31.9%) for PBC, 220 (20.6%) for AIH and 20 (1.9%) for overlap syndrome. There was a significant increase in the absolute number of procedures for PSC, with a yearly increase of 0.6 (95% confidence interval 0.1 to 1.2), whereas the absolute number of procedures for PBC and AIH remained stable. The proportion of transplantation procedures decreased for PBC and AIH but remained stable for PSC. Recipient age at transplantation increased over time for males with PBC (median 53 yr in 2000-2005 to 57 yr in 2012-2018, p = 0.03); whereas the median age among patients with AIH decreased, from 53 years in 2000-2005 to 44 years in 2006-2011 (p = 0.03). The Model for Endstage Liver Disease score at the time of transplantation increased over time for all AILDs, particularly AIH (median 16 in 2000-2005 v. 24 in 2012-2018, p < 0.001). There was a trend toward improved survival in the PBC group, with a 5-year survival rate of 81% in 2000-2005 and 90% in 2012-2018 (p = 0.06). CONCLUSION: Between 2000 and 2018, the absolute number of liver transplantation procedures in Canada increased for PSC but remained stable for PBC and AIH; proportionally, PBC and AIH decreased as indications for transplantation. Posttransplantation survival improved only for the PBC group. An improved understanding of trends and outcomes on a national scale among patients with AILD undergoing liver transplantation can identify disparities and areas for potential health care improvement.
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Colangitis Esclerosante , Hepatitis Autoinmune , Cirrosis Hepática Biliar , Hepatopatías , Trasplante de Hígado , Adulto , Canadá , Niño , Colangitis Esclerosante/diagnóstico , Colangitis Esclerosante/cirugía , Hepatitis Autoinmune/diagnóstico , Hepatitis Autoinmune/cirugía , Humanos , Cirrosis Hepática Biliar/diagnóstico , Cirrosis Hepática Biliar/cirugía , Masculino , Persona de Mediana EdadRESUMEN
Physical theories, for the most part, should be understood as modelling isolated subsystems of a larger universe; doing so, among other benefits, greatly clarifies the interpretation of the dynamical symmetries of those theories. Building on a general framework for the symmetries of isolated systems developed in the prequel to this paper, I apply that framework to field theory. The resultant analysis provides a general basis for interpreting the physical significance of symmetries according to their topological and asymptotic features: global symmetries in general, and local symmetries insofar as they preserve boundary conditions and are asymptotically nonvanishing and/or topologically nontrivial, can be understood as physical transformations of an isolated system against the assumed background of other systems. Other symmetries in general must be understood as mere redescription, though in certain circumstances even non-boundary-preserving local symmetries can be afforded physical significance. The analysis largely reproduces - and so can be seen as a theoretical justification for - general practice in contemporary physics.
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FísicaRESUMEN
I provide a conceptually-focused presentation of 'low-energy quantum gravity' (LEQG), the effective quantum field theory obtained from general relativity and which provides a well-defined theory of quantum gravity at energies well below the Planck scale. I emphasize the extent to which some such theory is required by the abundant observational evidence in astrophysics and cosmology for situations which require a simultaneous treatment of quantum-mechanical and gravitational effects, contra the often-heard claim that all observed phenomena can be accounted for either by classical gravity or by non-gravitational quantum mechanics, and I give a detailed account of the way in which a treatment of the theory as fluctuations on a classical background emerges as an approximation to the underlying theory rather than being put in by hand. I discuss the search for a Planck-scale quantum-gravity theory from the perspective of LEQG and give an introduction to the Cosmological Constant problem as it arises within LEQG.
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Physical theories, for the most part, should be understood as modelling isolated subsystems of a larger universe; doing so, among other benefits, greatly clarifies the interpretation of the dynamical symmetries of those theories. I provide a detailed framework for analysing the subsystem structure of physical theories and applying it to the interpretation of their symmetries: the core concept is subsystem recursivity, whereby interpretative conclusions about a sector of a theory can be deduced from considering subsystems of other models of the same theory. I illustrate the framework by extensive examples from nonrelativistic particle mechanics, and in particular from Newtonian theories of gravity. A sequel to the paper will apply the framework to the local and global symmetries of classical field theory.
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BACKGROUND AND AIMS: Identifying how the prognostic impact of performance status (PS) differs according to indication, era, and time period ("epoch") after liver transplantation (LT) could have implications for selection and treatment of patients on the waitlist. We used national data from the United Kingdom and Ireland to assess impact of PS on mortality separately for HCC and non-HCC recipients. APPROACH AND RESULTS: We assessed pre-LT PS using the 5-point modified Eastern Cooperative Oncology Group scale and used Cox regression methods to estimate hazard ratios (HRs) that compared posttransplantation mortality in different epochs of follow-up (0-90 days and 90 days to 1 year) and in different eras of transplantation (1995-2005 and 2006-2016). 2107 HCC and 10,693 non-HCC patients were included. One-year survival decreased with worsening PS in non-HCC recipients where 1-year survival was 91.9% (95% confidence interval [CI], 88.3-94.4) in those able to carry out normal activity (PS1) compared to 78.7% (95% CI, 76.7-80.5) in those completely reliant on care (PS5). For HCC patients, these estimates were 89.9% (95% CI, 85.4-93.2) and 83.1% (95% CI, 61.0-93.3), respectively. Reduction in survival in non-HCC patients with poorer PS was in the first 90 days after transplant, with no major effect observed between 90 days and 1 year. Adjustment for donor and recipient characteristics did not change the findings. Comparing era, post-LT mortality improved for HCC (adjusted HR, 0.55; 95% CI, 0.40-0.74) and non-HCC recipients (0.48; 95% CI, 0.42-0.55), but this did not differ according to PS score (P = 0.39 and 0.61, respectively). CONCLUSIONS: Impact on mortality of the recipient's pretransplant PS is principally limited to the first 3 months after LT. Over time, mortality has improved for both HCC and non-HCC recipients and across the full range of PS.
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Actividades Cotidianas , Trasplante de Hígado , Adulto , Carcinoma Hepatocelular/mortalidad , Femenino , Humanos , Neoplasias Hepáticas/mortalidad , Trasplante de Hígado/mortalidad , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Factores de TiempoRESUMEN
PURPOSE: The International Classification of Retinopathy of Prematurity is a consensus statement that creates a standard nomenclature for classification of retinopathy of prematurity (ROP). It was initially published in 1984, expanded in 1987, and revisited in 2005. This article presents a third revision, the International Classification of Retinopathy of Prematurity, Third Edition (ICROP3), which is now required because of challenges such as: (1) concerns about subjectivity in critical elements of disease classification; (2) innovations in ophthalmic imaging; (3) novel pharmacologic therapies (e.g., anti-vascular endothelial growth factor agents) with unique regression and reactivation features after treatment compared with ablative therapies; and (4) recognition that patterns of ROP in some regions of the world do not fit neatly into the current classification system. DESIGN: Review of evidence-based literature, along with expert consensus opinion. PARTICIPANTS: International ROP expert committee assembled in March 2019 representing 17 countries and comprising 14 pediatric ophthalmologists and 20 retinal specialists, as well as 12 women and 22 men. METHODS: The committee was initially divided into 3 subcommittees-acute phase, regression or reactivation, and imaging-each of which used iterative videoconferences and an online message board to identify key challenges and approaches. Subsequently, the entire committee used iterative videoconferences, 2 in-person multiday meetings, and an online message board to develop consensus on classification. MAIN OUTCOME MEASURES: Consensus statement. RESULTS: The ICROP3 retains current definitions such as zone (location of disease), stage (appearance of disease at the avascular-vascular junction), and circumferential extent of disease. Major updates in the ICROP3 include refined classification metrics (e.g., posterior zone II, notch, subcategorization of stage 5, and recognition that a continuous spectrum of vascular abnormality exists from normal to plus disease). Updates also include the definition of aggressive ROP to replace aggressive-posterior ROP because of increasing recognition that aggressive disease may occur in larger preterm infants and beyond the posterior retina, particularly in regions of the world with limited resources. ROP regression and reactivation are described in detail, with additional description of long-term sequelae. CONCLUSIONS: These principles may improve the quality and standardization of ROP care worldwide and may provide a foundation to improve research and clinical care.
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Retina/diagnóstico por imagen , Retinopatía de la Prematuridad/clasificación , Diagnóstico por Imagen , Progresión de la Enfermedad , Edad Gestacional , Humanos , Recién Nacido , Retinopatía de la Prematuridad/diagnósticoRESUMEN
BACKGROUND: Despite high waiting list mortality rates, concern still exists on the appropriateness of using livers donated after circulatory death (DCD). We compared mortality and graft loss in recipients of livers donated after circulatory or brainstem death (DBD) across two successive time periods. METHODS: Observational multinational data from the United Kingdom and Ireland were partitioned into two time periods (2008-2011 and 2012-2016). Cox regression methods were used to estimate hazard ratios (HRs) comparing the impact of periods on post-transplant mortality and graft failure. RESULTS: A total of 1176 DCD recipients and 3749 DBD recipients were included. Three-year patient mortality rates decreased markedly from 19.6 per cent in time period 1 to 10.4 per cent in time period 2 (adjusted HR 0.43, 95 per cent c.i. 0.30 to 0.62; P < 0.001) for DCD recipients but only decreased from 12.8 to 11.3 per cent (adjusted HR 0.96, 95 per cent c.i. 0.78 to 1.19; P = 0.732) in DBD recipients (P for interaction = 0.001). No time period-specific improvements in 3-year graft failure were observed for DCD (adjusted HR 0.80, 95% c.i. 0.61 to 1.05; P = 0.116) or DBD recipients (adjusted HR 0.95, 95% c.i. 0.79 to 1.14; P = 0.607). A slight increase in retransplantation rates occurred between time period 1 and 2 in those who received a DCD liver (from 7.3 to 11.8 per cent; P = 0.042), but there was no change in those receiving a DBD liver (from 4.9 to 4.5 per cent; P = 0.365). In time period 2, no difference in mortality rates between those receiving a DCD liver and those receiving a DBD liver was observed (adjusted HR 0.78, 95% c.i. 0.56 to 1.09; P = 0.142). CONCLUSION: Mortality rates more than halved in recipients of a DCD liver over a decade and eventually compared similarly to mortality rates in recipients of a DBD liver. Regions with high waiting list mortality may mitigate this by use of DCD livers.
Asunto(s)
Muerte Encefálica , Causas de Muerte , Supervivencia de Injerto , Trasplante de Hígado/mortalidad , Donantes de Tejidos , Femenino , Humanos , Irlanda/epidemiología , Trasplante de Hígado/efectos adversos , Masculino , Persona de Mediana Edad , Sistema de Registros , Reoperación/estadística & datos numéricos , Factores de Riesgo , Factores de Tiempo , Donantes de Tejidos/estadística & datos numéricos , Reino Unido/epidemiologíaRESUMEN
With more effective antiretroviral therapy (ART), people with HIV (PWH) are living longer and have more chronic diseases, including diabetes mellitus (DM). The prevalence of DM has been estimated in PWH previously, however there is less research regarding DM control. Our objectives were to determine the prevalence of DM and DM control and determine factors associated with DM control in a large urban cohort of PWH in care. We examined DC Cohort participants aged ≥18 years old to determine DM prevalence and to assess DM control (HbA1c measurement <7.0%). Demographic, clinical, and HIV-related factors associated with DM control were identified using multivariate logistic regression. The cohort of 5876 participants was predominantly male (71.3%), Non-Hispanic Black (78.1%) and had a median age of 52.0 years. DM prevalence was 17.4% (1023/5876). Among participants with recent HbA1c data available (39.9%) the proportion with DM control was 60.0% (245/408). In multivariate analysis, higher BMI (aOR: 0.47; 95% CI 0.28, 0.79) and use of non-insulin DM medication (aOR 0.43, 95% CI 0.25, 0.73) or insulin (aOR 0.010, 95% CI 0.04,0.24) compared to no medication use. Our findings suggest that individuals on medication for their DM likely need enhanced support to reach their treatment goals.
Asunto(s)
Diabetes Mellitus , Infecciones por VIH , Adolescente , Adulto , Estudios de Cohortes , Diabetes Mellitus/tratamiento farmacológico , Diabetes Mellitus/epidemiología , District of Columbia , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Masculino , Persona de Mediana Edad , PrevalenciaRESUMEN
AIMS: In 2003, an Australian woman was convicted by a jury of smothering and killing her four children over a 10-year period. Each child died suddenly and unexpectedly during a sleep period, at ages ranging from 19 days to 18 months. In 2019 we were asked to investigate if a genetic cause could explain the children's deaths as part of an inquiry into the mother's convictions. METHODS AND RESULTS: Whole genomes or exomes of the mother and her four children were sequenced. Functional analysis of a novel CALM2 variant was performed by measuring Ca2+-binding affinity, interaction with calcium channels and channel function. We found two children had a novel calmodulin variant (CALM2 G114R) that was inherited maternally. Three genes (CALM1-3) encode identical calmodulin proteins. A variant in the corresponding residue of CALM3 (G114W) was recently reported in a child who died suddenly at age 4 and a sibling who suffered a cardiac arrest at age 5. We show that CALM2 G114R impairs calmodulin's ability to bind calcium and regulate two pivotal calcium channels (CaV1.2 and RyR2) involved in cardiac excitation contraction coupling. The deleterious effects of G114R are similar to those produced by G114W and N98S, which are considered arrhythmogenic and cause sudden cardiac death in children. CONCLUSION: A novel functional calmodulin variant (G114R) predicted to cause idiopathic ventricular fibrillation, catecholaminergic polymorphic ventricular tachycardia, or mild long QT syndrome was present in two children. A fatal arrhythmic event may have been triggered by their intercurrent infections. Thus, calmodulinopathy emerges as a reasonable explanation for a natural cause of their deaths.