Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 518
Filtrar
1.
Medicine (Baltimore) ; 101(39): e30860, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36181012

RESUMO

BACKGROUND: The use of extracorporeal cardiopulmonary resuscitation (ECPR) has improved survival in patients with cardiac arrest; however, factors predicting survival remain poorly characterized. A systematic review and meta-analysis was conducted to examine the predictors of survival of ECPR in pediatric patients. METHODS: We searched EMBASE, PubMed, SCOPUS, and the Cochrane Library from 2010 to 2021 for pediatric ECPR studies comparing survivors and non-survivors. Thirty outcomes were analyzed and classified into 5 categories: demographics, pre-ECPR laboratory measurements, pre-ECPR co-morbidities, intra-ECPR characteristics, and post-ECPR complications. RESULTS: Thirty studies (n = 3794) were included. Pooled survival to hospital discharge (SHD) was 44% (95% CI: 40%-47%, I2 = 67%). Significant predictors of survival for pediatric ECPR include the pre-ECPR lab measurements of PaO2, pH, lactate, PaCO2, and creatinine, pre-ECPR comorbidities of single ventricle (SV) physiology, renal failure, sepsis, ECPR characteristics of extracorporeal membrane oxygenation (ECMO) duration, ECMO flow rate at 24 hours, cardiopulmonary resuscitation (CPR) duration, shockable rhythm, intra-ECPR neurological complications, and post-ECPR complications of pulmonary hemorrhage, renal failure, and sepsis. CONCLUSION: Prior to ECPR initiation, increased CPR duration and lactate levels had among the highest associations with mortality, followed by pH. After ECPR initiation, pulmonary hemorrhage and neurological complications were most predictive for survival. Clinicians should focus on these factors to better inform potential prognosis of patients, advise appropriate patient selection, and improve ECPR program effectiveness.


Assuntos
Reanimação Cardiopulmonar , Doenças do Sistema Nervoso , Insuficiência Renal , Sepse , Criança , Creatinina , Humanos , Ácido Láctico , Oxigênio , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
2.
Nature ; 602(7898): 585-589, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35197615

RESUMO

Fast radio bursts (FRBs) are flashes of unknown physical origin1. The majority of FRBs have been seen only once, although some are known to generate multiple flashes2,3. Many models invoke magnetically powered neutron stars (magnetars) as the source of the emission4,5. Recently, the discovery6 of another repeater (FRB 20200120E) was announced, in the direction of the nearby galaxy M81, with four potential counterparts at other wavelengths6. Here we report observations that localized the FRB to a globular cluster associated with M81, where it is 2 parsecs away from the optical centre of the cluster. Globular clusters host old stellar populations, challenging FRB models that invoke young magnetars formed in a core-collapse supernova. We propose instead that FRB 20200120E originates from a highly magnetized neutron star formed either through the accretion-induced collapse of a white dwarf, or the merger of compact stars in a binary system7. Compact binaries are efficiently formed inside globular clusters, so a model invoking them could also be responsible for the observed bursts.

3.
Ultrasound Obstet Gynecol ; 59(3): 325-334, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34159662

RESUMO

OBJECTIVE: To assess the rate and type of genetic diagnosis and clinical outcome of cases of fetal cardiomyopathy (CM) during two eras, in order to examine the impact of advanced genetic testing and improved perinatal management strategies. METHODS: All diagnoses of fetal CM in Alberta, Canada, encountered between 2003 and 2019, were reviewed retrospectively. Genetic, cardiac and non-cardiac diagnoses and clinical outcome were documented. Cases with CM secondary to extracardiac pathology and maternal conditions were excluded. Cases diagnosed in the earlier era of the study period (2003-2012) were compared with those diagnosed in the later era (2013-2019). RESULTS: Thirty-eight cases of fetal CM met the inclusion criteria. Median gestational age (GA) at diagnosis was 22.8 (range, 13.4-37.4) weeks. Associated structural heart disease was present in 39% (15/38) of cases and 24% (9/38) had arrhythmia. Hydrops was identified in 29% (11/38) of cases at presentation, and a further 18% (7/38) developed hydrops later in gestation. Twenty-six percent (10/38) of cases underwent termination of pregnancy and 24% (9/38) had intrauterine death. Of liveborn cases, neonatal death occurred in 16% (3/19), late death occurred in 21% (4/19) and 63% (12/19) were alive at the last follow-up. Excluding cases that had termination of pregnancy and those with a liveborn infant who received planned palliative care, the rate of neonatal survival was higher in the later compared with the earlier era (69% (11/16) vs 45% (5/11)), although the difference was not statistically significant (P = 0.26). A genetic etiology was confirmed in 39% (15/38) of cases and strongly suspected in 24% (9/38). A significantly higher proportion of cases had a confirmed or strongly suspected genetic etiology in the later era compared with in the earlier era (76% (19/25) vs 38% (5/13); P = 0.04). CONCLUSIONS: In the recent era, a higher proportion of fetal CM cases had a confirmed or strongly suspected genetic etiology than reported previously. Based on comparison with older series, modern perinatal management strategies may not have a significant impact on neonatal survival in cases of fetal CM; however, a larger study would be better powered to detect more subtle differences. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Cardiomiopatias , Resultado da Gravidez , Cardiomiopatias/genética , Edema , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Gravidez , Estudos Retrospectivos , Ultrassonografia Pré-Natal
4.
J Heart Lung Transplant ; 40(5): 368-376, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33642140

RESUMO

BACKGROUND: The size of the Fontan population with end-stage heart failure is growing. In this population, heart transplantation has been the only option. This study sought to investigate the efficacy of ventricular assist device (VAD) support in Fontan patients. METHODS: We conducted a retrospective study of Fontan patients in the Advanced Cardiac Therapies Improving Outcomes Network. We evaluated patient characteristics, and the clinical and physiologic outcomes after VAD implantation. RESULTS: We identified 45 Fontan patients implanted with VAD. The average age of patients was 10 years (interquartile range: 4.5-18) and 30% were female. The majority had a morphologic right ventricle (69%), moderate or greater ventricular dysfunction (83%), and moderate or greater atrioventricular valve regurgitation (65%). The majority of implants were as a bridge to transplantation (76%), and the majority of patients were Interagency Registry for Mechanically Assisted Circulatory Support Profile 2 (56%). The most commonly employed device was the Medtronic HeartWare HVAD (56%). A total of 13 patients were discharged on device support, and 67% of patients experienced adverse events, the most common of which were neurologic (25%). At 1 year after device implantation, the rate of transplantation was 69.5%, 9.2% of patients continued to be VAD supported, and 21.3% of patients had died. Hemodynamically, VAD was effective in decreasing both Fontan and ventricular end-diastolic pressures in some individuals. CONCLUSIONS: VAD is effective in supporting patients with end-stage Fontan failure awaiting heart transplantation. Future research should focus on identifying clinical and physiologic characteristics predictive of a favorable response to VAD support.


Assuntos
Técnica de Fontan , Insuficiência Cardíaca/cirurgia , Coração Auxiliar , Sistema de Registros , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Transplante de Coração , Humanos , Masculino , Estudos Retrospectivos , Resultado do Tratamento
5.
Epidemiol Infect ; 149: e42, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33551007

RESUMO

During a disease outbreak, healthcare workers (HCWs) are essential to treat infected individuals. However, these HCWs are themselves susceptible to contracting the disease. As more HCWs get infected, fewer are available to provide care for others, and the overall quality of care available to infected individuals declines. This depletion of HCWs may contribute to the epidemic's severity. To examine this issue, we explicitly model declining quality of care in four differential equation-based susceptible, infected and recovered-type models with vaccination. We assume that vaccination, recovery and survival rates are affected by quality of care delivered. We show that explicitly modelling HCWs and accounting for declining quality of care significantly alters model-predicted disease outcomes, specifically case counts and mortality. Models neglecting the decline of quality of care resulting from infection of HCWs may significantly under-estimate cases and mortality. These models may be useful to inform health policy that may differ for HCWs and the general population. Models accounting for declining quality of care may therefore improve the management interventions considered to mitigate the effects of a future outbreak.


Assuntos
Epidemias , Pessoal de Saúde , Nível de Saúde , Modelos Biológicos , Humanos , Mortalidade , Garantia da Qualidade dos Cuidados de Saúde , Vacinação
6.
J Hosp Infect ; 110: 194-200, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33549768

RESUMO

BACKGROUND: Reducing COVID-19 transmission relies on controlling droplet and aerosol spread. Fluorescein staining reveals microscopic droplets. AIM: To compare the droplet spread in non-laminar and laminar air flow operating theatres. METHODS: A 'cough-generator' was fixed to a theatre trolley at 45°. Fluorescein-stained 'secretions' were projected on to a series of calibrated targets. These were photographed under UV light and 'source detection' software measured droplet splatter size and distance. FINDINGS: The smallest droplet detected was ∼120 µm and the largest ∼24,000 µm. An average of 25,862 spots was detected in the non-laminar theatre, compared with 11,430 in the laminar theatre (56% reduction). The laminar air flow mainly affected the smaller droplets (<1000 µm). The surface area covered with droplets was: 6% at 50 cm, 1% at 2 m, and 0.5% at 3 m in the non-laminar air flow; and 3%, 0.5%, and 0.2% in the laminar air flow, respectively. CONCLUSION: Accurate mapping of droplet spread in clinical environments is possible using fluorescein staining and image analysis. The laminar air flow affected the smaller droplets but had limited effect on larger droplets in our 'aerosol-generating procedure' cough model. Our results indicate that the laminar air flow theatre requires similar post-surgery cleaning to the non-laminar, and staff should consider full personal protective equipment for medium- and high-risk patients.


Assuntos
Aerossóis , Microbiologia do Ar , COVID-19/prevenção & controle , COVID-19/transmissão , Transmissão de Doença Infecciosa/estatística & dados numéricos , Ambiente Controlado , Salas Cirúrgicas/estatística & dados numéricos , Humanos , SARS-CoV-2
7.
AJNR Am J Neuroradiol ; 42(2): 279-284, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33093131

RESUMO

BACKGROUND AND PURPOSE: Various patterns of leukoencephalopathy have been described in coronavirus disease 2019 (COVID-19). In this article, we aimed to describe the clinical and imaging features of acute disseminated leukoencephalopathy in critically ill patients with COVID-19 and the imaging evolution during a short-term follow-up. MATERIALS AND METHODS: We identified and reviewed the clinical data, laboratory results, imaging findings, and outcomes for 8 critically ill patients with COVID-19 with acute disseminated leukoencephalopathy. RESULTS: All patients demonstrated multiple areas of white matter changes in both cerebral hemispheres; 87.5% (7/8) of patients had a posterior predilection. Four patients (50%) had short-term follow-up imaging within a median of 17 days after the first MR imaging; they developed brain atrophy, and their white matter lesions evolved into necrotizing cystic cavitations. All (8/8) patients had inflammatory cytokine release syndrome as demonstrated by elevated interleukin-6, D-dimer, lactate dehydrogenase, erythrocyte sedimentation rate, C-reactive protein, and ferritin levels. Most (7/8; 87.5%) patients were on prolonged ventilator support (median, 44.5 days; interquartile range, 20.5 days). These patients had poor functional outcomes (6/8 [75%] patients were discharged with mRS 5) and high mortality (2/8, 25%). CONCLUSIONS: Critically ill patients with COVID-19 can develop acute disseminated leukoencephalopathy that evolves into cystic degeneration of white matter lesions with brain atrophy during a short period, which we dubbed virus-associated necrotizing disseminated acute leukoencephalopathy. This may be the result of COVID-19-related endothelial injury, cytokine storm, or thrombotic microangiopathy.


Assuntos
COVID-19/diagnóstico por imagem , Leucoencefalopatias/diagnóstico por imagem , Adulto , Idoso , Atrofia , Encéfalo/diagnóstico por imagem , COVID-19/complicações , COVID-19/mortalidade , Estado Terminal , Síndrome da Liberação de Citocina/etiologia , Feminino , Humanos , Leucoencefalopatias/etiologia , Leucoencefalopatias/mortalidade , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Respiração Artificial , Estudos Retrospectivos , Trombose/diagnóstico por imagem , Trombose/etiologia , Resultado do Tratamento , Substância Branca/diagnóstico por imagem
8.
Microbiol Res ; 242: 126628, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33153885

RESUMO

The management of soilborne root diseases in pulse crops is challenged by a limited range of resistance sources and often a complete absence of in-crop management options. Therefore, alternative management strategies need to be developed. We evaluated disease limiting interactions between the rhizobia species Mesorhizobium ciceri, and the oomycete pathogen Phytophthora medicaginis, which causes Phytophthora root rot (PRR) of chickpea (Cicer arietinum). For the PRR susceptible var. Sonali plants, post-pathogen M. ciceri inoculation significantly improved probability of plant survival when compared to P. medicaginis infected plants only pre-inoculated with M. ciceri (75 % versus 35 %, respectively). Potential mechanisms for these effects were investigated: rhizobia inoculation benefits to plant nodulation were not demonstrated, but the highest nodule N-fixation activity of P. medicaginis inoculated plants occurred for the post-pathogen M. ciceri treatment; rhizobia inoculation treatment did not reduce lesion development but certain combinations of microbial inoculation led to significant reduction in root growth. Microcosm studies, however, showed that the presence of M. ciceri reduced growth of P. medicaginis isolates. Putative chickpea disease resistance gene expression was evaluated using qPCR in var. Sonali roots. When var. Sonali plants were treated with M. ciceri post-P. medicaginis inoculation, the gene regulation in the plant host became more similar to PRR moderately resistant var. PBA HatTrick. These results suggest that M. ciceri application post P. medicaginis inoculation may improve plant survival by inducing defense responses similar to a PRR moderately resistant chickpea variety. Altogether, these results indicate that order of microbial succession can significantly affect PRR plant survial in susceptible chickpea under controlled conditions and improved plant survival effects are due to a number of different mechanisms including improved host nutrition, through direct inhibiton of pathogen growth, as well as host defense priming.


Assuntos
Agentes de Controle Biológico/farmacologia , Phytophthora/efeitos dos fármacos , Doenças das Plantas/terapia , Rhizobium/metabolismo , Cicer , Resistência à Doença/efeitos dos fármacos , Resistência à Doença/genética , Expressão Gênica , Mesorhizobium , Phytophthora/patogenicidade , Doenças das Plantas/microbiologia , Nodulação , Raízes de Plantas
9.
Diabetes Res Clin Pract ; 169: 108460, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32971153

RESUMO

OBJECTIVES: Diabetes has been shown to be a risk factor for corona virus disease-2019 (COVID-19) infection. The characteristics of patients with diabetes vulnerable to this infection are less specified. We aim to present the characteristics of patients with diabetes admitted to hospital with COVID-19. DESIGN: A retrospective case series. SETTING: A single clinical centre in the UK. METHODS: We have retrospectively collected the demographics, medical characteristics and outcome of all patients with diabetes admitted to hospital over two-week period with COVID-19 infection. All cases were diagnosed by a reverse transcription polymerase chain reaction (RT-PCR) of pharyngeal and nasal swabs. RESULTS: A total of 71 COVID-19 patients were admitted during the study period of whom 16 (22.5%) patients had diabetes and were included in this case series. There was no significant difference between patients with compared to those without diabetes regarding age, gender or clinical presentation. However, comorbidities were more common in patients with diabetes specially hypertension {75% v 36.4%, a difference of 38.6%, 95% confidence interval (CI) 6.5-58.3} and chronic kidney disease (37.5 v 5.5, a difference of 32% (1.6-51.6). Patients with diabetes were significantly more obese than those without diabetes (56.2% v 21.8% a difference of 34.4%, 95% CI 7.7-61.1). About one third (31.3%) of patients with diabetes were frail. Mean {standard deviation (SD)} duration of diabetes was 10 (2.8) years and mean (SD) HbA1c was 60.3 (15.6) mmol/mol. The use of angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs) and non-steroidal anti-inflammatory drugs (NSAIDs) was common (37.5%, 25% and 18.8% respectively). There was no significant difference in the outcomes between patients with compared to those without diabetes. CONCLUSION: Patients with diabetes hospitalised for COVID-19 were significantly more obese and had high prevalence of comorbidities than those without diabetes. Other features of patients with diabetes and COVID-19 infection included long duration of diabetes, less tight glycaemic control and common use of ACE inhibitors, ARBs and NSAIDs.


Assuntos
COVID-19/complicações , Diabetes Mellitus/epidemiologia , Hospitalização/estatística & dados numéricos , Hipertensão/epidemiologia , SARS-CoV-2/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , COVID-19/virologia , Estudos de Casos e Controles , Comorbidade , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/virologia , Feminino , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/virologia , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco
10.
SN Compr Clin Med ; 2(8): 1218-1222, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32838171

RESUMO

The COVID-19 pandemic initially started in China then spread to Europe. It is not known whether COVID-19 affects patients differently across the two continents. We aimed to describe our cohort of patients admitted to a single British centre with COVID-19 in comparison to a Chinese cohort of similar size and admitted over a similar time period to Chinese centres. We present a comparison of 62 Chinese and 71 British cases hospitalised for COVID-19. Cases in both sites were confirmed by a positive RT-PCR of nasopharyngeal swabs. Comparison analysis highlighted some differences between both populations. The most striking difference is the significantly older age of the British population (72% of the British ≥ 66 years compared to only 3% of the Chinese patients, difference of 69%, 95% confidence interval (CI) 68.3% to 69.7%, respectively) and the associated significant premorbid conditions (85% of patients vs 32%, difference of 53%, 95% CI 52 to 54%, respectively). Gastrointestinal and general symptoms were more common clinical presentation in the British while respiratory symptoms were more prominent in the Chinese cohort. Mortality was significantly higher in the British cohort 14% compared to none in the Chinese cohort (difference of 14%, 95% CI 13.7 to 14.3%). We conclude that COVID-19 does present differently in these two cohorts, but the apparent differences in the clinical presentations could be explained by the inherent differences in the demographics and case mix between both countries.

11.
Crit Care Med ; 48(6): e489-e497, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32317603

RESUMO

OBJECTIVES: Tracheal intubation in critically ill children with shock poses a risk of hemodynamic compromise. Ketamine has been considered the drug of choice for induction in these patients, but limited data exist. We investigated whether the administration of ketamine for tracheal intubation in critically ill children with or without shock was associated with fewer adverse hemodynamic events compared with other induction agents. We also investigated if there was a dose dependence for any association between ketamine use and adverse hemodynamic events. DESIGN: We performed a retrospective analysis using prospectively collected observational data from the National Emergency Airway Registry for Children database from 2013 to 2017. SETTING: Forty international PICUs participating in the National Emergency Airway Registry for Children. PATIENTS: Critically ill children 0-17 years old who underwent tracheal intubation in a PICU. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The association between ketamine exposure as an induction agent and the occurrence of adverse hemodynamic events during tracheal intubation including dysrhythmia, hypotension, and cardiac arrest was evaluated. We used multivariable logistic regression to account for patient, provider, and practice factors with robust SEs to account for clustering by sites. Of 10,750 tracheal intubations, 32.0% (n = 3,436) included ketamine as an induction agent. The most common diagnoses associated with ketamine use were sepsis and/or shock (49.7%). After adjusting for potential confounders and sites, ketamine use was associated with fewer hemodynamic tracheal intubation associated adverse events compared with other agents (adjusted odds ratio, 0.74; 95% CI, 0.58-0.95). The interaction term between ketamine use and indication for shock was not significant (p = 0.11), indicating ketamine effect to prevent hemodynamic adverse events is consistent in children with or without shock. CONCLUSIONS: Ketamine use for tracheal intubation is associated with fewer hemodynamic tracheal intubation-associated adverse events.


Assuntos
Analgésicos/uso terapêutico , Hemodinâmica/efeitos dos fármacos , Intubação Intratraqueal/métodos , Ketamina/uso terapêutico , Choque/epidemiologia , Adolescente , Fatores Etários , Analgésicos/administração & dosagem , Analgésicos/efeitos adversos , Criança , Pré-Escolar , Estado Terminal , Feminino , Humanos , Lactente , Recém-Nascido , Unidades de Terapia Intensiva Pediátrica , Ketamina/administração & dosagem , Ketamina/efeitos adversos , Masculino , Estudos Retrospectivos
12.
Phys Rev Lett ; 121(5): 054802, 2018 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-30118307

RESUMO

We report on the observation of incoherent Cherenkov radiation emitted by a 5.3 GeV positron beam circulating in the Cornell electron-positron storage ring as the beam passes in the close vicinity of the surface of a fused silica radiator (i.e., at a distance larger than 0.8 mm). The shape of the radiator was designed in order to send the Cherenkov photons towards the detector, consisting of a compact optical system equipped with an intensified camera. The optical system allows both the measurements of 2D images and angular distribution including polarization study. The corresponding light intensity has been measured as a function of the distance between the beam and the surface of the radiator and has shown a good agreement with theoretical predictions. For highly relativistic particles, a large amount of incoherent radiation is produced in a wide spectral range. A light yield of 0.8×10^{-3} photon per particle per turn has been measured at a wavelength of 600±10 nm in a 2 cm long radiator and for an impact parameter of 1 mm. This will find applications in accelerators as noninvasive beam diagnostics for both leptons and hadrons.

13.
Early Hum Dev ; 120: 80-87, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29496329

RESUMO

AIMS: Hypoxic ischaemic encephalopathy (HIE) remains a significant cause of long term neurodisability despite therapeutic hypothermia (TH). Infants with mild HIE, representing 50% of those with HIE, are perceived as low risk and are currently not eligible for TH [1]. This review examines the available evidence of outcome in term infants with mild HIE. METHODS: Medline, Embase and Cochrane Clinical Trials databases were searched in March 2017. Studies with well-defined HIE grading at birth and standardised neurodevelopmental assessment at ≥18 months were included. Abnormal outcome was defined as death, cerebral palsy or standardised neurodevelopmental test score more than 1 standard deviation below the mean. RESULT: Twenty studies were included. Abnormal outcome was reported in 86/341 (25%) of infants. There was insufficient evidence to examine the effect of TH on outcome. CONCLUSION: A significant proportion of infants with mild HIE have abnormal outcome at follow up.


Assuntos
Encefalopatias/terapia , Hipotermia Induzida/métodos , Doenças do Recém-Nascido/terapia , Encefalopatias/fisiopatologia , Deficiências do Desenvolvimento/etiologia , Humanos , Hipóxia-Isquemia Encefálica/fisiopatologia , Hipóxia-Isquemia Encefálica/terapia , Recém-Nascido , Doenças do Recém-Nascido/fisiopatologia , Resultado do Tratamento
14.
Plant Cell Environ ; 40(10): 2250-2260, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28710809

RESUMO

UVB radiation is biologically active; in plants, it can induce a range of molecular, biochemical, morphological and developmental responses. Although much progress has been made in elucidating UVB perception and signalling pathways under controlled laboratory conditions, understanding of the adaptive, ecological role of UVB responses is still very limited. In this study, we looked at the functional role of UVR8 under outdoor light conditions, by studying growth, photosynthetic competence and accumulation of UV absorbing pigments in a mutant lacking functional UVR8 protein. It was found that the influence of UVB on morphology is restricted to summer and is independent of UVR8. In contrast, UVB had an effect on the content of UV-absorbing pigments and the maximal efficiency of photosystem II of photosynthesis in the uvr8-1 mutant throughout the year. It is concluded that the UVR8 photoreceptor plays a role throughout the year, in the temperate climate zone, even when UVB levels are relatively low.


Assuntos
Absorção de Radiação , Proteínas de Arabidopsis/metabolismo , Arabidopsis/anatomia & histologia , Arabidopsis/efeitos da radiação , Proteínas Cromossômicas não Histona/metabolismo , Fotorreceptores de Plantas/metabolismo , Pigmentos Biológicos/metabolismo , Raios Ultravioleta , Biomassa , Mutação/genética , Fenóis/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Desenvolvimento Vegetal/efeitos da radiação , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Análise de Regressão , Estações do Ano
15.
Oncogene ; 36(30): 4288-4298, 2017 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-28346421

RESUMO

Pancreatic cancer has a devastating prognosis, with an overall 5-year survival rate of ~8%, restricted treatment options and characteristic molecular heterogeneity. SerpinB2 expression, particularly in the stromal compartment, is associated with reduced metastasis and prolonged survival in pancreatic ductal adenocarcinoma (PDAC) and our genomic analysis revealed that SERPINB2 is frequently deleted in PDAC. We show that SerpinB2 is required by stromal cells for normal collagen remodelling in vitro, regulating fibroblast interaction and engagement with collagen in the contracting matrix. In a pancreatic cancer allograft model, co-injection of PDAC cancer cells and SerpinB2-/- mouse embryonic fibroblasts (MEFs) resulted in increased tumour growth, aberrant remodelling of the extracellular matrix (ECM) and increased local invasion from the primary tumour. These tumours also displayed elevated proteolytic activity of the primary biochemical target of SerpinB2-urokinase plasminogen activator (uPA). In a large cohort of patients with resected PDAC, we show that increasing uPA mRNA expression was significantly associated with poorer survival following pancreatectomy. This study establishes a novel role for SerpinB2 in the stromal compartment in PDAC invasion through regulation of stromal remodelling and highlights the SerpinB2/uPA axis for further investigation as a potential therapeutic target in pancreatic cancer.


Assuntos
Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas/patologia , Inibidor 2 de Ativador de Plasminogênio/metabolismo , Microambiente Tumoral , Animais , Carcinoma Ductal Pancreático/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patologia , Perfilação da Expressão Gênica , Humanos , Camundongos , Microscopia Eletrônica de Varredura , Neoplasias Pancreáticas/metabolismo , Transcriptoma
16.
Equine Vet J ; 49(4): 493-500, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27397866

RESUMO

REASON FOR PERFORMING STUDY: Injury to the tendons and ligaments of the equine stifle is a common cause of lameness in horses. Individual radiographic localisation of each tendon and ligament of the stifle has not been previously reported or demonstrated in multiple radiographic projections. OBJECTIVE: To create a series of radiographs identifying the origins and/or insertions of the tendons and ligaments of the equine stifle. STUDY DESIGN: Descriptive study of radiographic anatomy. METHODS: The location of all entheses were determined by gross dissection. The proximal tibia and fibula, distal femur, patella and menisci were isolated from one horse and used as a template. A series of 4 radiographs was obtained with each enthesis identified with barium paste. The radiographic landmarks for each enthesis were described and the best projection(s) for evaluation of each structure of interest identified. RESULTS: Forty-eight radiographic images were produced that demonstrated the best radiographic projections to define each enthesis. CONCLUSIONS: Radiography is the imaging modality most frequently used to evaluate the equine stifle. The images presented here will serve as a guide for evaluating radiographs of the equine stifle, particularly identifying avulsions and enthesopathies of ligamentous and tendinous origins and insertions.


Assuntos
Tecido Conjuntivo/anatomia & histologia , Tecido Conjuntivo/diagnóstico por imagem , Cavalos/anatomia & histologia , Joelho de Quadrúpedes/diagnóstico por imagem , Animais , Fêmur , Ligamentos , Joelho de Quadrúpedes/anatomia & histologia , Joelho de Quadrúpedes/lesões , Tendões , Tíbia
18.
Nature ; 531(7592): 70-3, 2016 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-26935696

RESUMO

Cosmic rays are the highest-energy particles found in nature. Measurements of the mass composition of cosmic rays with energies of 10(17)-10(18) electronvolts are essential to understanding whether they have galactic or extragalactic sources. It has also been proposed that the astrophysical neutrino signal comes from accelerators capable of producing cosmic rays of these energies. Cosmic rays initiate air showers--cascades of secondary particles in the atmosphere-and their masses can be inferred from measurements of the atmospheric depth of the shower maximum (Xmax; the depth of the air shower when it contains the most particles) or of the composition of shower particles reaching the ground. Current measurements have either high uncertainty, or a low duty cycle and a high energy threshold. Radio detection of cosmic rays is a rapidly developing technique for determining Xmax (refs 10, 11) with a duty cycle of, in principle, nearly 100 per cent. The radiation is generated by the separation of relativistic electrons and positrons in the geomagnetic field and a negative charge excess in the shower front. Here we report radio measurements of Xmax with a mean uncertainty of 16 grams per square centimetre for air showers initiated by cosmic rays with energies of 10(17)-10(17.5) electronvolts. This high resolution in Xmax enables us to determine the mass spectrum of the cosmic rays: we find a mixed composition, with a light-mass fraction (protons and helium nuclei) of about 80 per cent. Unless, contrary to current expectations, the extragalactic component of cosmic rays contributes substantially to the total flux below 10(17.5) electronvolts, our measurements indicate the existence of an additional galactic component, to account for the light composition that we measured in the 10(17)-10(17.5) electronvolt range.

19.
Ir Med J ; 109(9): 466, 2016 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-28125180

RESUMO

In Ireland, Warfarin is the primary anticoagulant prescribed in the secondary prevention of provoked DVT. We completed a comprehensive cost analysis of a trial group of 24 patients treated with Rivaroxaban (between November 2013 and December 2014), versus a control group treated with Warfarin (between January 2008 and November 2013). The groups were matched for gender (3/7 M/F ratio), DVT type (5 proximal, 19 distal DVTs), provoking factor (20 traumatic, 4 atraumatc), and age. We calculated the cost for each group based on drug administration and clinic costs (labour, sample analysis, and additional costs). Warfarin patients attended clinic 14.58 times; Rivaroxaban patients attended 2.92 times. Overall, the cost per patient on Rivaroxaban is €273.30 versus €260.68 with warfarin. This excludes patient costs which would further increase cost of Warfarin therapy.


Assuntos
Anticoagulantes/economia , Inibidores do Fator Xa/economia , Rivaroxabana/economia , Trombose Venosa/tratamento farmacológico , Varfarina/economia , Anticoagulantes/administração & dosagem , Custos e Análise de Custo , Custos de Medicamentos , Inibidores do Fator Xa/administração & dosagem , Feminino , Humanos , Irlanda , Masculino , Rivaroxabana/administração & dosagem , Prevenção Secundária/economia , Trombose Venosa/etiologia , Varfarina/administração & dosagem
20.
Pediatr Transplant ; 19(8): 896-905, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26381803

RESUMO

We sought to determine temporal changes in COD and identify COD-specific risk factors in pediatric primary HTx recipients. Using the ISHLT registry, time-dependent hazard of death after pediatric HTx, stratified by COD, was analyzed by multiphasic parametric hazard modeling with multivariable regression models for risk factor analysis. The proportion of pediatric HTx deaths from each of cardiovascular cause, allograft vasculopathy, and malignancy increased over time, while all other COD decreased post-HTx. Pre-HTx ECMO was associated with increased risk of death from graft failure (HR 2.43; p < 0.001), infection (HR 2.85; p < 0.001), and MOF (HR 2.22; p = 0.001), while post-HTx ECMO was associated with death from cerebrovascular events/bleed (HR 2.55; p = 0.001). CHD was associated with deaths due to pulmonary causes (HR 1.78; p = 0.007) or infection (HR 1.72; p < 0.001). Non-adherence was a significant risk factor for all cardiac COD, notably graft failure (HR 1.66; p = 0.001) and rejection (HR 1.89; p < 0.001). Risk factors related to specific COD are varied across different temporal phases post-HTx. Increased understanding of these factors will assist in risk stratification, guide anticipatory clinical decisions, and potentially improve patient survival.


Assuntos
Causas de Morte , Transplante de Coração/mortalidade , Adolescente , Animais , Criança , Pré-Escolar , Feminino , Seguimentos , Saúde Global , Humanos , Lactente , Recém-Nascido , Masculino , Análise Multivariada , Avaliação de Resultados em Cuidados de Saúde , Complicações Pós-Operatórias/mortalidade , Sistema de Registros , Análise de Regressão , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...