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1.
Int J Equity Health ; 22(1): 205, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37794428

RESUMO

BACKGROUND: Sars-CoV-2, the causative agent of COVID-19, has led to more than 226,000 deaths in the UK and multiple risk factors for mortality including age, sex and deprivation have been identified. This study aimed to identify which individual indicators of the Scottish Index of Multiple Deprivation (SIMD), an area-based deprivation index, were predictive of mortality. METHODS: This was a prospective cohort study of anonymised electronic health records of 710 consecutive patients hospitalised with Covid-19 disease between March and June 2020 in the Lothian Region of Southeast Scotland. Data sources included automatically extracted data from national electronic platforms and manually extracted data from individual admission records. Exposure variables of interest were SIMD quintiles and 12 indicators of deprivation deemed clinically relevant selected from the SIMD. Our primary outcome was mortality. Age and sex adjusted univariable and multivariable analyses were used to determine measures of association between exposures of interest and the primary outcome. RESULTS: After adjusting for age and sex, we found an increased risk of mortality in the more deprived SIMD quintiles 1 and 3 (OR 1.75, CI 0.99-3.08, p = 0.053 and OR 2.17, CI 1.22-3.86, p = 0.009, respectively), but this association was not upheld in our multivariable model containing age, sex, Performance Status and clinical parameters of severity at admission. Of the 12 pre-selected indicators of deprivation, two were associated with greater mortality in our multivariable analysis: income deprivation rate categorised by quartile (Q4 (most deprived): 2.11 (1.20-3.77) p = 0.011)) and greater than expected hospitalisations due to alcohol per SIMD data zone (1.96 (1.28-3.00) p = 0.002)). CONCLUSIONS: SIMD as an aggregate measure of deprivation was not predictive of mortality in our cohort when other exposure measures were accounted for. However, we identified a two-fold increased risk of mortality in patients residing in areas with greater income-deprivation and/or number of hospitalisations due to alcohol. In areas where aggregate measures fail to capture pockets of deprivation, exploring the impact of specific SIMD indicators may be helpful in targeting resources to residents at risk of poorer outcomes from Covid-19.


Assuntos
COVID-19 , Humanos , Estudos de Coortes , Fatores Socioeconômicos , Estudos Prospectivos , SARS-CoV-2 , Escócia/epidemiologia
2.
Phys Chem Chem Phys ; 24(19): 11486-11490, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35506979

RESUMO

Electronic delocalization is essential to the properties of π-conjugated molecules. We introduce the inter-fragment delocalization index (IFDI) as an easy-to-use computational method for quantifying the electronic delocalization in π-conjugated oligomers and molecular wire models. We show that the IFDI is related to the torsion barriers of π-conjugated dimers, and to the single-molecule conductance of several π-conjugated fragments. The IFDI is a useful screening technique for comparing different π-conjugated subunits as components in organic electronics, since it can quantify the influence of substitution position, structure, and (anti)aromaticity on delocalization.

3.
Soil Sci Soc Am J ; 85(1): 172-183, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34853488

RESUMO

Phosphorus is an essential nutrient for crops. Precise spatiotemporal application of P fertilizer can improve plant P acquisition and reduce run-off losses of P. Optimizing application would benefit from understanding the dynamics of P release from a fertilizer pellet into bulk soil, which requires space- and time-resolved measurements of P concentration in soil solutions. In this study, we combined microdialysis and X-ray computed tomography to investigate P transport in soil. Microdialysis probes enabled repeated solute sampling from one location with minimal physical disturbance, and their small dimensions permitted spatially resolved monitoring. We observed a rapid initial release of P from the source, producing high dissolved P concentrations within the first 24 h, followed by a decrease in dissolved P over time compatible with adsorption onto soil particles. Soils with greater bulk density (i.e., reduced soil porosity) impeded the P pulse movement, which resulted in a less homogeneous distribution of total P in the soil column at the end of the experiment. The model fit to the data showed that the observed phenomena can be explained by diffusion and adsorption. The results showed that compared with conventional measurement techniques (e.g., suction cups), microdialysis measurements present a less invasive alternative. The time-resolved measurements ultimately highlighted rapid P dynamics that require more attention for improving P use efficiency.

4.
J Shoulder Elbow Surg ; 25(9): e256-64, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26968090

RESUMO

BACKGROUND: Little is known about the short-term temporal outcomes of an arthroscopic capsular release for adhesive capsulitis (frozen shoulder). Specifically, it is not known how immediate the improvements are and how quickly patients return to normal function after an arthroscopic release. METHODS: The study included 140 shoulders in 133 patients with idiopathic adhesive capsulitis who underwent a complete arthroscopic release of the shoulder capsule, performed by a single surgeon in a day surgery setting. Patient-reported pain and shoulder function were evaluated with the use of Likert scales, and an independent examiner assessed shoulder strength and range of motion preoperatively and at 1 week, 6 weeks, 12 weeks, and 24 weeks postoperatively. RESULTS: Arthroscopic capsular release resulted in immediate improvements in pain, functional outcomes, and range of motion (P < .0001). External rotation increased from 21° ± 17° (mean ± standard deviation) to 76° ± 17° at 1 week. Passive range of shoulder motion improved at 1 week, deteriorated slightly at 6 weeks, and then continued to improve at 12 and 24 weeks. Before surgery, 38% of patients reported that they "always" experienced extreme pain. This proportion reduced to 30% (P < .0001) at 1 week postoperatively and 2% (P < .0001) at 24 weeks postoperatively. There were no complications. CONCLUSIONS: Patients who underwent an arthroscopic capsular release for idiopathic adhesive capsulitis experienced significant reductions in pain, improvements in range of motion, and improvements in overall shoulder function in the first postoperative week. These immediate improvements in pain and function continue to improve at 6, 12, and 24 weeks postoperatively.


Assuntos
Artroscopia , Bursite/cirurgia , Liberação da Cápsula Articular , Articulação do Ombro/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular , Medição da Dor , Amplitude de Movimento Articular , Estudos Retrospectivos , Rotação
6.
Nutr Bull ; 49(2): 180-188, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38605430

RESUMO

In January 2021, we assessed the implications of temporary regulations in the United Kingdom allowing pubs and restaurants to operate on a takeaway basis without instigating a change of use. Local authorities (LAs) across the North-East of England were unaware of any data regarding the take-up of these regulations, partially due to ongoing capacity issues; participants also raised health concerns around takeaway use increasing significantly. One year on, we repeated the study aiming to understand the impact of these regulations on the policy and practice of key professional groups. Specifically, we wanted to understand if LAs were still struggling with staff capacity to address the regulations, whether professionals still had public health trepidations, and if any unexpected changes had occurred across the local food environment because of the pandemic. We conversed with 16 public health professionals, planners and environmental health officers across seven LAs throughout the North-East of England via focus groups and interviews. Data collated were analysed via an inductive and semantic, reflexive-thematic approach. Through analysis of the data, three themes were generated and are discussed throughout: popular online delivery services as a mediator to increased takeaway usage; potential long-term health implications and challenges; continued uncertainty regarding the temporary regulations. This paper highlights important changes to local food environments, which public health professionals should be aware of, so they are better equipped to tackle health inequalities across urban and sub-urban areas.


Assuntos
COVID-19 , Restaurantes , SARS-CoV-2 , Humanos , COVID-19/prevenção & controle , COVID-19/epidemiologia , Inglaterra/epidemiologia , Restaurantes/legislação & jurisprudência , Pandemias/prevenção & controle , Fast Foods , Saúde Pública/legislação & jurisprudência , Grupos Focais , Política Nutricional/legislação & jurisprudência
7.
Infect Prev Pract ; 5(4): 100308, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38107242

RESUMO

Background: High Consequence Infectious Diseases (HCIDs), have the potential to cause pandemics and require particular focus for preparedness due to their high mortality rates. The application of Personal Protective Equipment (PPE) for HCIDs is complex and carries significant risk of Health Care Worker (HCW) contamination if done incorrectly. Previous reviews have reported a lack of information on the nature of training provided and the ideal timing of repeat training to best retain skills. Simulation Based Mastery Learning (SBML) is a methodology for skill acquisition which encompasses deliberate practice and repeated assessment until the learner achieves a pre-set Mastery standard. SBML has been demonstrated to improve competence, skill retention and patient outcomes in other clinical procedures. SBML has not been previously studied or utilised in HCID PPE training. Aim: We aimed to increase the likelihood of safe clinical practice by evidencing that Lothian modified SBML for PPE effectively prepares our priority learners. Methods: A quasi-experimental within group post-test design was used. Learners undertook a modified SBML programme which included two-hour asynchronous and two-hour synchronous components. Findings: 11 learners (10 infectious diseases registrars and 1 infectious diseases consultant) were enrolled in the programme with 8 completing all stages, all of whom achieved the Mastery passing standard. The resources were highly rated by learners with the exemplar videos of skills highlighted as particularly useful. Self-assessed preparedness for each skill increased following pre-learning and synchronous sessions. Conclusion: Modified SBML can be used as an effective methodology for the training and assessment of HCWs in the donning and doffing of HCID PPE.

8.
Hum Reprod ; 27(4): 1223-6, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22328556

RESUMO

BACKGROUND: Screening of gamete donors can reduce but cannot eliminate the risks for medical problems in donor-conceived offspring. We present a case of gonosomal mosaicism discovered in an anonymous sperm donor after receiving two reports of neurofibromatosis type 1 (NF1) in donor-conceived offspring, to illustrate that long-term, systematic investigation of health issues in donors and offspring can be invaluable to the welfare of these individuals. METHODS: A repeat physical evaluation and ophthalmology examination were performed on the donor. DNA samples were examined by RTPCR fragment analysis, multiplex ligation-dependent probe amplification (MLPA) and targeted array-comparative genomic hybridization (aCGH). RESULTS: Gonosomal mosaicism for a deletion mutation in the NF1 gene was identified in 20% of sperm and a smaller percentage of lymphocytes. CONCLUSIONS: Long-term communication of medical information among donors, recipients and donor-conceived offspring is beneficial for the health management of all parties. Development of a secure, coordinated data system is critical to achieving this goal. Recommendations are provided for management and communication of critical information based on this experience.


Assuntos
Mosaicismo , Neurofibromatose 1/genética , Deleção de Sequência , Espermatozoides , Doadores de Tecidos , California , Aconselhamento Genético , Humanos , Masculino , Prontuários Médicos , Medição de Risco
9.
J R Coll Physicians Edinb ; 52(3): 204-212, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36369813

RESUMO

BACKGROUND: COVID-19 mortality risk factors have been established in large cohort studies; long-term mortality outcomes are less documented. METHODS: We performed multivariable logistic regression to identify factors associated with in-patient mortality and intensive care unit (ICU) admission in symptomatic COVID-19 patients admitted to hospitals in South-East Scotland from 1st March to 30th June 2020. One-year mortality was reviewed. RESULTS: Of 726 patients (median age 72; interquartile range: 58-83 years, 55% male), 104 (14%) required ICU admission and 199 (27%) died in hospital. A further 64 died between discharge and 30th June 2021 (36% overall 1-year mortality). Stepwise logistic regression identified age >79 (odds ratio (OR), 4.77 (95% confidence interval (CI), 1.96-12.75)), male sex (OR, 1.83 (95% CI, 1.21-2.80)) and higher European Cooperative Oncology Group/World Health Organization performance status as associated with higher mortality risk. DISCUSSION: Poor functional baseline was the predominant independent risk factor for mortality in COVID-19. More than one-third of individuals had died by 1 year following admission.


Assuntos
COVID-19 , Humanos , Masculino , Idoso , Feminino , SARS-CoV-2 , Unidades de Terapia Intensiva , Hospitalização , Fatores de Risco , Mortalidade Hospitalar , Estudos Retrospectivos
10.
Oncogene ; 41(18): 2540-2554, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35301407

RESUMO

Low-risk gestational trophoblastic neoplasia including choriocarcinoma is often effectively treated with Methotrexate (MTX) as a first line therapy. However, MTX resistance (MTX-R) occurs in at least ≈33% of cases. This can sometimes be salvaged with actinomycin-D but often requires more toxic combination chemotherapy. Moreover, additional therapy may be needed and, for high-risk patients, 5% still die from the multidrug-resistant disease. Consequently, new treatments that are less toxic and could reverse MTX-R are needed. Here, we compared the proteome/phosphoproteome of MTX-resistant and sensitive choriocarcinoma cells using quantitative mass-spectrometry to identify therapeutically actionable molecular changes associated with MTX-R. Bioinformatics analysis of the proteomic data identified cell cycle and DNA damage repair as major pathways associated with MTX-R. MTX-R choriocarcinoma cells undergo cell cycle delay in G1 phase that enables them to repair DNA damage more efficiently through non-homologous end joining in an ATR-dependent manner. Increased expression of cyclin-dependent kinase 4 (CDK4) and loss of p16Ink4a in resistant cells suggested that CDK4 inhibition may be a strategy to treat MTX-R choriocarcinoma. Indeed, inhibition of CDK4/6 using genetic silencing or the clinically relevant inhibitor, Palbociclib, induced growth inhibition both in vitro and in an orthotopic in vivo mouse model. Finally, targeting the ATR pathway, genetically or pharmacologically, re-sensitised resistant cells to MTX in vitro and potently prevented the growth of MTX-R tumours in vivo. In short, we identified two novel therapeutic strategies to tackle MTX-R choriocarcinoma that could rapidly be translated into the clinic.


Assuntos
Coriocarcinoma , Quinase 6 Dependente de Ciclina/metabolismo , Metotrexato , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Coriocarcinoma/tratamento farmacológico , Coriocarcinoma/genética , Coriocarcinoma/metabolismo , Quinase 4 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/metabolismo , Dactinomicina , Feminino , Humanos , Metotrexato/farmacologia , Camundongos , Gravidez , Proteômica
11.
Plant Soil ; 460(1-2): 647-665, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720206

RESUMO

AIMS: We sought to develop a novel experimental system which enabled application of iodinated contrast media to in vivo plant roots intact in soil and was compatible with time-resolved synchrotron X-ray computed tomography imaging. The system was developed to overcome issues of low contrast to noise within X-ray computed tomography images of plant roots and soil environments, the latter of which can complicate image processing and result in the loss of anatomical information. METHODS: To demonstrate the efficacy of the system we employ the novel use of both synchrotron X-ray computed tomography and synchrotron X-ray fluorescence mapping to capture the translocation of the contrast media through root vasculature into the leaves. RESULTS: With the application of contrast media we identify fluid flow in root vasculature and visualise anatomical features, which are otherwise often only observable in ex vivo microscopy, including: the xylem, metaxylem, pith, fibres in aerenchyma and leaf venation. We are also able to observe interactions between aerenchyma cross sectional area and solute transport in the root vasculature with depth. CONCLUSIONS: Our novel system was capable of successfully delivering sufficient contrast media into root and leaf tissues such that anatomical features could be visualised and internal fluid transport observed. We propose that our system could be used in future to study internal plant transport mechanisms and parameterise models for fluid flow in plants. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11104-020-04784-x.

12.
Artigo em Inglês | MEDLINE | ID: mdl-34063033

RESUMO

Links between heat exposure and congenital anomalies have not been explored in detail despite animal data and other strands of evidence that indicate such links are likely. We reviewed articles on heat and congenital anomalies from PubMed and Web of Science, screening 14,880 titles and abstracts in duplicate for articles on environmental heat exposure during pregnancy and congenital anomalies. Thirteen studies were included. Most studies were in North America (8) or the Middle East (3). Methodological diversity was considerable, including in temperature measurement, gestational windows of exposure, and range of defects studied. Associations were detected between heat exposure and congenital cardiac anomalies in three of six studies, with point estimates highest for atrial septal defects. Two studies with null findings used self-reported temperature exposures. Hypospadias, congenital cataracts, renal agenesis/hypoplasia, spina bifida, and craniofacial defects were also linked with heat exposure. Effects generally increased with duration and intensity of heat exposure. However, some neural tube defects, gastroschisis, anopthalmia/microphthalmia and congenital hypothyroidism were less frequent at higher temperatures. While findings are heterogenous, the evidence raises important concerns about heat exposure and birth defects. Some heterogeneity may be explained by biases in reproductive epidemiology. Pooled analyses of heat impacts using registers of congenital anomalies are a high priority.


Assuntos
Anormalidades Congênitas , Cardiopatias Congênitas , Anormalidades Congênitas/epidemiologia , Anormalidades Congênitas/etiologia , Feminino , Cardiopatias Congênitas/epidemiologia , Cardiopatias Congênitas/etiologia , Temperatura Alta , Humanos , Oriente Médio , América do Norte , Gravidez , Temperatura
13.
BMJ ; 371: m3811, 2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-33148618

RESUMO

OBJECTIVE: To assess whether exposure to high temperatures in pregnancy is associated with increased risk for preterm birth, low birth weight, and stillbirth. DESIGN: Systematic review and random effects meta-analysis. DATA SOURCES: Medline and Web of Science searched up to September 2018, updated in August 2019. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Clinical studies on associations between high environmental temperatures, and preterm birth, birth weight, and stillbirths. RESULTS: 14 880 records and 175 full text articles were screened. 70 studies were included, set in 27 countries, seven of which were countries with low or middle income. In 40 of 47 studies, preterm births were more common at higher than lower temperatures. Exposures were classified as heatwaves, 1°C increments, and temperature threshold cutoff points. In random effects meta-analysis, odds of a preterm birth rose 1.05-fold (95% confidence interval 1.03 to 1.07) per 1°C increase in temperature and 1.16-fold (1.10 to 1.23) during heatwaves. Higher temperature was associated with reduced birth weight in 18 of 28 studies, with considerable statistical heterogeneity. Eight studies on stillbirths all showed associations between temperature and stillbirth, with stillbirths increasing 1.05-fold (1.01 to 1.08) per 1°C rise in temperature. Associations between temperature and outcomes were largest among women in lower socioeconomic groups and at age extremes. The multiple temperature metrics and lag analyses limited comparison between studies and settings. CONCLUSIONS: Although summary effect sizes are relatively small, heat exposures are common and the outcomes are important determinants of population health. Linkages between socioeconomic status and study outcomes suggest that risks might be largest in low and middle income countries. Temperature rises with global warming could have major implications for child health. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD 42019140136 and CRD 42018118113.


Assuntos
Temperatura Alta/efeitos adversos , Recém-Nascido de Baixo Peso , Nascimento Prematuro/epidemiologia , Natimorto/epidemiologia , Feminino , Humanos , Recém-Nascido , Gravidez , Fatores de Risco
14.
Dis Model Mech ; 12(2)2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30760495

RESUMO

Lung cancer is the leading cause of cancer-related death. Two-thirds of cases are diagnosed at an advanced stage that is refractory to curative treatment. Therefore, strategies for the early detection of lung cancer are urgently sought. Total circulating free DNA (cfDNA) and tumour-derived circulating tumour DNA (ctDNA) are emerging as important biomarkers within a 'liquid biopsy' for monitoring human disease progression and response to therapy. Owing to the late clinical diagnosis of lung adenocarcinoma, the potential for cfDNA and ctDNA as early detection biomarkers remains unexplored. Here, using a Cre-regulated genetically engineered mouse model of lung adenocarcinoma development, driven by KrasG12D (the KrasLSL-G12D mouse), we serially tracked the release of cfDNA/ctDNA and compared this with tumour burden as determined by micro-computed tomography (CT). To monitor ctDNA, a droplet digital PCR assay was developed to permit discrimination of the KrasLox-G12D allele from the KrasLSL-G12D and KrasWT alleles. We show that micro-CT correlates with endpoint histology and is able to detect pre-malignant tumours with a combined volume larger than 7 mm3 Changes in cfDNA/ctDNA levels correlate with micro-CT measurements in longitudinal sampling and are able to monitor the emergence of lesions before the adenoma-adenocarcinoma transition. Potentially, this work has implications for the early detection of human lung adenocarcinoma using ctDNA/cfDNA profiling.A video abstract for this article is available at https://youtu.be/Ku8xJJyGs3UThis article has an associated First Person interview with the joint first authors of the paper.


Assuntos
Ácidos Nucleicos Livres/sangue , Detecção Precoce de Câncer , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/diagnóstico , Mutação/genética , Lesões Pré-Cancerosas/sangue , Lesões Pré-Cancerosas/diagnóstico , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Alelos , Animais , Modelos Animais de Doenças , Feminino , Integrases/metabolismo , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Masculino , Camundongos Endogâmicos C57BL , Lesões Pré-Cancerosas/diagnóstico por imagem , Lesões Pré-Cancerosas/patologia , Proteínas Proto-Oncogênicas p21(ras)/sangue , Recombinação Genética/genética , Reprodutibilidade dos Testes , Carga Tumoral , Microtomografia por Raio-X
15.
Am J Clin Pathol ; 152(1): 86-90, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-31165167

RESUMO

OBJECTIVES: To apply a simple method to validate testing for albumin, glucose, lactate dehydrogenase (LDH) and total protein (TP) in peritoneal, pleural, and cerebrospinal fluids (CSF) at a hospital in Liberia. METHODS: Serum and body fluid specimens were mixed to create 100% serum and 25%, 50%, 75%, and 100% fluid tubes, which were tested on a Biotecnica BT3500. Differences less than 10% between calculated and measured concentrations were considered acceptable. RESULTS: The means (confidence intervals) of the percent differences were: albumin/peritoneal 12.8 (6.0-19.7), albumin/pleural 2.8 (1.3-4.2), albumin/CSF 4.8 (2.2-7.5), glucose/peritoneal 4.0 (1.9-6.0), glucose/pleural 4.4 (3.1-5.7), glucose/CSF 2.9 (1.8-4.0), LDH/peritoneal 9.5 (6.3-12.7), LDH/pleural 9.5 (5.4-13.6), LDH/CSF 9.2 (5.2-13.3), TP/peritoneal 7.6 (3.8-11.4), TP/pleural 3.8 (1.5-6.2), and TP/CSF 4.5 (1.0-8.1). CONCLUSIONS: All mean differences except for one were less than 10%, allowing for the adoption of clinical testing. The mixing study is a low-cost method for quality-assured testing that can be performed by resource-limited laboratories.


Assuntos
Albuminas/análise , Líquidos Corporais/química , Glucose/análise , L-Lactato Desidrogenase/análise , Proteínas/análise , Humanos , Libéria
16.
R Soc Open Sci ; 6(10): 190769, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31824700

RESUMO

This investigation establishes a system of gold nanoparticles that show good colloidal stability as an X-ray computed tomography (XCT) contrast agent under soil conditions. Gold nanoparticles offer numerous beneficial traits for experiments in biology including: comparatively minimal phytotoxicity, X-ray attenuation of the material and the capacity for functionalization. However, soil salinity, acidity and surface charges can induce aggregation and destabilize gold nanoparticles, hence in biomedical applications polymer coatings are commonly applied to gold nanoparticles to enhance stability in the in vivo environment. Here we first demonstrate non-coated nanoparticles aggregate in soil-water solutions. We then show coating with a polyethylene glycol (PEG) layer prevents this aggregation. To demonstrate this, PEG-coated nanoparticles were drawn through flow columns containing soil and were shown to be stable; this is in contrast with control experiments using silica and alumina-packed columns. We further determined that a suspension of coated gold nanoparticles which fully saturated soil maintained stability over at least 5 days. Finally, we used time resolved XCT imaging and image based models to approximate nanoparticle diffusion as similar to that of other typical plant nutrients diffusing in water. Together, these results establish the PEGylated gold nanoparticles as potential contrast agents for XCT imaging in soil.

17.
Rev Sci Instrum ; 89(2): 024705, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29495834

RESUMO

Two-dimensional materials offer a novel platform for the development of future quantum technologies. However, the electrical characterisation of topological insulating states, non-local resistance, and bandgap tuning in atomically thin materials can be strongly affected by spurious signals arising from the measuring electronics. Common-mode voltages, dielectric leakage in the coaxial cables, and the limited input impedance of alternate-current amplifiers can mask the true nature of such high-impedance states. Here, we present an optical isolator circuit which grants access to such states by electrically decoupling the current-injection from the voltage-sensing circuitry. We benchmark our apparatus against two state-of-the-art measurements: the non-local resistance of a graphene Hall bar and the transfer characteristic of a WS2 field-effect transistor. Our system allows the quick characterisation of novel insulating states in two-dimensional materials with potential applications in future quantum technologies.

18.
Plant Methods ; 13: 76, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29118820

RESUMO

Background: Wheat is one of the most widely grown crop in temperate climates for food and animal feed. In order to meet the demands of the predicted population increase in an ever-changing climate, wheat production needs to dramatically increase. Spike and grain traits are critical determinants of final yield and grain uniformity a commercially desired trait, but their analysis is laborious and often requires destructive harvest. One of the current challenges is to develop an accurate, non-destructive method for spike and grain trait analysis capable of handling large populations. Results: In this study we describe the development of a robust method for the accurate extraction and measurement of spike and grain morphometric parameters from images acquired by X-ray micro-computed tomography (µCT). The image analysis pipeline developed automatically identifies plant material of interest in µCT images, performs image analysis, and extracts morphometric data. As a proof of principle, this integrated methodology was used to analyse the spikes from a population of wheat plants subjected to high temperatures under two different water regimes. Temperature has a negative effect on spike height and grain number with the middle of the spike being the most affected region. The data also confirmed that increased grain volume was correlated with the decrease in grain number under mild stress. Conclusions: Being able to quickly measure plant phenotypes in a non-destructive manner is crucial to advance our understanding of gene function and the effects of the environment. We report on the development of an image analysis pipeline capable of accurately and reliably extracting spike and grain traits from crops without the loss of positional information. This methodology was applied to the analysis of wheat spikes can be readily applied to other economically important crop species.

20.
Clin Cancer Res ; 20(20): 5311-21, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25165097

RESUMO

PURPOSE: Loss of epigenetic gene regulation through altered long noncoding RNA (lncRNA) expression seems important in human cancer. LncRNAs have diagnostic and therapeutic potential, and offer insights into the biology disease, but little is known of their expression in urothelial cancer. Here, we identify differentially expressed lncRNAs with potential regulatory functions in urothelial cancer. EXPERIMENTAL DESIGN: The expression of 17,112 lncRNAs and 22,074 mRNAs was determined using microarrays in 83 normal and malignant urothelial (discovery) samples and selected RNAs with qPCR in 138 samples for validation. Significantly differentially expressed RNAs were identified and stratified according to tumor phenotype. siRNA knockdown, functional assays, and whole-genome transcriptomic profiling were used to identify potential roles of selected lncRNAs. RESULTS: We observed upregulation of many lncRNAs in urothelial cancer that was distinct to corresponding, more balanced changes for mRNAs. In general, lncRNA expression reflected disease phenotype. We identified 32 lncRNAs with potential roles in disease progression. Focusing upon a promising candidate, we implicate upregulation of AB074278 in apoptosis avoidance and the maintenance of a proproliferative state in cancer through a potential interaction with EMP1, a tumor suppressor and a negative regulator of cell proliferation. CONCLUSIONS: We report differential expression profiles for numerous lncRNA in urothelial cancer. We identify phenotype-specific expression and a potential mechanistic target to explain this observation. Further studies are required to validate lncRNAs as prognostic biomarkers in this disease.


Assuntos
Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , RNA Longo não Codificante/genética , Neoplasias da Bexiga Urinária/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/genética , Proliferação de Células , Análise por Conglomerados , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fenótipo , Prognóstico , Interferência de RNA , RNA Mensageiro/genética , Carga Tumoral , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia
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