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1.
Br J Cancer ; 127(10): 1827-1836, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36224402

RESUMO

BACKGROUND: Patients living with cancer are at a significantly increased risk of morbidity and mortality after infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). This systematic review aims to investigate the current available evidence about the immunogenicity of SARS-CoV-2 booster vaccines in patients living with cancer. METHODS: A systematic search was undertaken for studies published until March 1, 2022. A systematic narrative review was undertaken to include all studies that evaluated the efficacy of booster vaccines against SARS-CoV-2 in patients with cancer. RESULTS: Fifteen studies encompassing 1205 patients with cancer were included. We found that a booster vaccine dose induced a higher response in patients with solid cancer as compared to haematological malignancies. Recent systemic anticancer therapy does not appear to affect seroconversion in solid organ malignancies, however, there is an association between B-cell depleting therapies and poor seroconversion in haematological patients. CONCLUSIONS: Third booster vaccination induces an improved antibody response to SARS-CoV-2 in adults with haematological and solid cancer, relative to patients who only receive two doses. Access to vaccination boosters should be made available to patients at risk of poor immunological responses, and the provision of fourth doses may be of benefit to this vulnerable population. REGISTRATION: PROSPERO number CRD42021270420.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Neoplasias , Adulto , Humanos , Anticorpos Antivirais , Formação de Anticorpos , COVID-19/prevenção & controle , Vacinas contra COVID-19/administração & dosagem , Neoplasias/terapia , Neoplasias/induzido quimicamente , SARS-CoV-2 , Vacinação , Vacinas Virais/efeitos adversos
2.
BMC Cancer ; 22(1): 458, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35473510

RESUMO

AIM: To independently assess the impact of mandatory testing using an extended DPYD variant panel (ToxNav®) and consequent dose adjustment of Capecitabine/5-FU on recorded quantitative toxicity, symptoms of depression, and hospital costs. METHODS: We used propensity score matching (PSM) to match 466 patients tested with ToxNav® with 1556 patients from a historical cohort, and performed regression analysis to estimate the impact of ToxNav®on toxicity, depression, and hospital costs. RESULTS: ToxNav® appeared to reduce the likelihood of experiencing moderate (OR: 0.59; 95%CI: 0.45-0.77) and severe anaemia (OR: 0.55; 95%CI: 0.33-0.90), and experience of pain for more than 4 days a week (OR: 0.50; 95%CI: 0.30-0.83), while it increased the likelihood of mild neutropenia (OR: 1.73; 95%CI: 1.27-2.35). It also reduced the cost of chemotherapy by 12% (95%CI: 3-31) or £9765, the cost of non-elective hospitalisation by 23% (95%CI: 8-36) or £2331, and the cost of critical care by 21% (95%CI: 2-36) or £1219 per patient. For the DPYD variant associated with critical risk of toxicity (rs3918290), the improved non-elective hospital costs were > £20,000, whereas variants associated with hand-foot syndrome toxicity had no detectable cost improvement. CONCLUSION: Upfront testing of DPYD variants appears to reduce the toxicity burden of Capecitabine and 5-FU in cancer patients and can lead to substantial hospital cost savings, only if the dose management of the drugs in response to variants detected is standardised and regulated.


Assuntos
Di-Hidrouracila Desidrogenase (NADP) , Custos Hospitalares , Capecitabina/efeitos adversos , Humanos , Pontuação de Propensão , Reino Unido
3.
Postgrad Med J ; 95(1123): 266-270, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31129621

RESUMO

PURPOSE: Active patient participation in safety pathways has demonstrated benefits in reducing preventable errors, especially in relation to hand hygiene and surgical site marking. The authors sought to examine patient participation in a range of safety-related behaviours as well as factors that influence this, such as gender, education, age and language. DESIGN: A 20-point questionnaire was employed in a London teaching hospital to explore safety-related behaviours, particularly assessing patient's willingness to challenge healthcare professionals and engagement in taking an active role in their own care while in hospital. Data was also collected on participant demographic details including gender, age, ethnicity, English language proficiency and education status. RESULTS: 85% of the 175 patients surveyed would consider bringing a list of their medications to hospital, but only 60% would bring a list of previous surgeries. Only 45% would actively engage in the WHO Safer Surgery Checklist and over three quarters (80%) would not challenge doctors and nurses regarding hand hygiene, believing that they would cause offence. Female patients who had tertiary education, were fluent in English and less than 60 years of age were statistically more likely to feel responsible for their own safety and take an active role in safety-related behaviour while in hospital (p<0.05). CONCLUSIONS: Many patients are not engaged in safety-related behaviour and do not challenge healthcare professionals on safety issues. Older male patients who were not tertiary educated or fluent in English need to be empowered to take an active role in such behaviour. Further research is required to investigate how to achieve this.


Assuntos
Lista de Checagem , Higiene das Mãos/normas , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Participação do Paciente/estatística & dados numéricos , Segurança do Paciente/normas , Adulto , Etnicidade/estatística & dados numéricos , Feminino , Pesquisas sobre Atenção à Saúde , Conhecimentos, Atitudes e Prática em Saúde , Hospitais de Ensino , Humanos , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Avaliação das Necessidades , Projetos Piloto
4.
Phys Biol ; 12(6): 066001, 2015 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-26403334

RESUMO

While the majority of cells in an organism are static and remain relatively immobile in their tissue, migrating cells occur commonly during developmental processes and are crucial for a functioning immune response. The mode of migration has been described in terms of various types of random walks. To understand the details of the migratory behaviour we rely on mathematical models and their calibration to experimental data. Here we propose an approximate Bayesian inference scheme to calibrate a class of random walk models characterized by a specific, parametric particle re-orientation mechanism to observed trajectory data. We elaborate the concept of transition matrices (TMs) to detect random walk patterns and determine a statistic to quantify these TM to make them applicable for inference schemes. We apply the developed pipeline to in vivo trajectory data of macrophages and neutrophils, extracted from zebrafish that had undergone tail transection. We find that macrophage and neutrophils exhibit very distinct biased persistent random walk patterns, where the strengths of the persistence and bias are spatio-temporally regulated. Furthermore, the movement of macrophages is far less persistent than that of neutrophils in response to wounding.


Assuntos
Movimento Celular , Macrófagos/fisiologia , Neutrófilos/fisiologia , Peixe-Zebra/fisiologia , Animais , Teorema de Bayes , Leucócitos/fisiologia , Modelos Biológicos
5.
Immunol Cell Biol ; 91(1): 60-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23165607

RESUMO

The recruitment and migration of macrophages and neutrophils is an important process during the early stages of the innate immune system in response to acute injury. Transgenic pu.1:EGFP zebrafish permit the acquisition of leukocyte migration trajectories during inflammation. Currently, these high-quality live-imaging data are mainly analysed using general statistics, for example, cell velocity. Here, we present a spatio-temporal analysis of the cell dynamics using transition matrices, which provide information of the type of cell migration. We find evidence that leukocytes exhibit types of migratory behaviour, which differ from previously described random walk processes. Dimethyl sulfoxide treatment decreased the level of persistence at early time points after wounding and ablated temporal dependencies observed in untreated embryos. We then use pharmacological inhibition of p38 and c-Jun N-terminal kinase mitogen-activated protein kinases to determine their effects on in vivo leukocyte migration patterns and discuss how they modify the characteristics of the cell migration process. In particular, we find that their respective inhibition leads to decreased and increased levels of persistent motion in leukocytes following wounding. This example shows the high level of information content, which can be gained from live-imaging data if appropriate statistical tools are used.


Assuntos
Movimento Celular/imunologia , Proteínas Quinases JNK Ativadas por Mitógeno/imunologia , Leucócitos/imunologia , Proteínas de Peixe-Zebra/imunologia , Peixe-Zebra/imunologia , Proteínas Quinases p38 Ativadas por Mitógeno/imunologia , Animais , Animais Geneticamente Modificados , Movimento Celular/efeitos dos fármacos , Crioprotetores/farmacologia , Dimetil Sulfóxido/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Leucócitos/citologia , Inibidores de Proteínas Quinases/farmacologia , Ferimentos e Lesões/genética , Ferimentos e Lesões/imunologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/antagonistas & inibidores , Proteínas de Peixe-Zebra/genética , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/genética
6.
Obes Rev ; 24(9): e13597, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37463862

RESUMO

This systematic review critically appraised and synthesized evidence from economic evaluations of interventions targeting childhood excess weight. We conducted systematic searches in 11 databases from inception to April 19, 2023. Studies were eligible if they evaluated interventions targeting children up to 18 years and the study intervention(s) targeted childhood excess weight or sought to improve diet or physical activity, regardless of the type of economic evaluation or the underpinning study design. We synthesized evidence using narrative synthesis methods. One-hundred fifty-one studies met the eligibility criteria and were classified into three groups based on the intervention approach: prevention-only (13 studies), prevention and treatment (100 studies), and treatment-only (38 studies). The predominant setting and study design differed considerably between the three groups of studies. However, compared with usual care, most interventions were deemed cost-effective. The study participants' ages, sex, and socioeconomic status were crucial to intervention cost-effectiveness. Interventions whose effects were projected beyond childhood, such as bariatric surgery, lower protein infant formula, and home-based general practitioner consultations, tended to be cost-effective. However, cost-effectiveness was sensitive to the assumptions underlying the persistence and intensity of such effects. Our findings can inform future recommendations on the conduct of economic evaluations of interventions targeting childhood overweight and obesity, as well as practice and policy recommendations.


Assuntos
Cirurgia Bariátrica , Obesidade Infantil , Criança , Humanos , Obesidade Infantil/prevenção & controle , Análise Custo-Benefício , Dieta , Exercício Físico
7.
Sci Rep ; 13(1): 11327, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37491478

RESUMO

Patients with cancer are at increased risk of hospitalisation and mortality following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, the SARS-CoV-2 phenotype evolution in patients with cancer since 2020 has not previously been described. We therefore evaluated SARS-CoV-2 on a UK populationscale from 01/11/2020-31/08/2022, assessing case-outcome rates of hospital assessment(s), intensive care admission and mortality. We observed that the SARS-CoV-2 disease phenotype has become less severe in patients with cancer and the non-cancer population. Case-hospitalisation rates for patients with cancer dropped from 30.58% in early 2021 to 7.45% in 2022 while case-mortality rates decreased from 20.53% to 3.25%. However, the risk of hospitalisation and mortality remains 2.10x and 2.54x higher in patients with cancer, respectively. Overall, the SARS-CoV-2 disease phenotype is less severe in 2022 compared to 2020 but patients with cancer remain at higher risk than the non-cancer population. Patients with cancer must therefore be empowered to live more normal lives, to see loved ones and families, while also being safeguarded with expanded measures to reduce the risk of transmission.


Assuntos
COVID-19 , Neoplasias , Humanos , Masculino , Feminino , Estudos de Casos e Controles , Resultado do Tratamento , Neoplasias/complicações , Neoplasias/epidemiologia , COVID-19/complicações , COVID-19/epidemiologia , Inglaterra/epidemiologia , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais
8.
JAMA Oncol ; 9(2): 188-196, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36547970

RESUMO

Importance: Accurate identification of patient groups with the lowest level of protection following COVID-19 vaccination is important to better target resources and interventions for the most vulnerable populations. It is not known whether SARS-CoV-2 antibody testing has clinical utility for high-risk groups, such as people with cancer. Objective: To evaluate whether spike protein antibody vaccine response (COV-S) following COVID-19 vaccination is associated with the risk of SARS-CoV-2 breakthrough infection or hospitalization among patients with cancer. Design, Setting, and Participants: This was a population-based cross-sectional study of patients with cancer from the UK as part of the National COVID Cancer Antibody Survey. Adults with a known or reported cancer diagnosis who had completed their primary SARS-CoV-2 vaccination schedule were included. This analysis ran from September 1, 2021, to March 4, 2022, a period covering the expansion of the UK's third-dose vaccination booster program. Interventions: Anti-SARS-CoV-2 COV-S antibody test (Elecsys; Roche). Main Outcomes and Measures: Odds of SARS-CoV-2 breakthrough infection and COVID-19 hospitalization. Results: The evaluation comprised 4249 antibody test results from 3555 patients with cancer and 294 230 test results from 225 272 individuals in the noncancer population. The overall cohort of 228 827 individuals (patients with cancer and the noncancer population) comprised 298 479 antibody tests. The median age of the cohort was in the age band of 40 and 49 years and included 182 741 test results (61.22%) from women and 115 737 (38.78%) from men. There were 279 721 tests (93.72%) taken by individuals identifying as White or White British. Patients with cancer were more likely to have undetectable anti-S antibody responses than the general population (199 of 4249 test results [4.68%] vs 376 of 294 230 [0.13%]; P < .001). Patients with leukemia or lymphoma had the lowest antibody titers. In the cancer cohort, following multivariable correction, patients who had an undetectable antibody response were at much greater risk for SARS-CoV-2 breakthrough infection (odds ratio [OR], 3.05; 95% CI, 1.96-4.72; P < .001) and SARS-CoV-2-related hospitalization (OR, 6.48; 95% CI, 3.31-12.67; P < .001) than individuals who had a positive antibody response. Conclusions and Relevance: The findings of this cross-sectional study suggest that COV-S antibody testing allows the identification of patients with cancer who have the lowest level of antibody-derived protection from COVID-19. This study supports larger evaluations of SARS-CoV-2 antibody testing. Prevention of SARS-CoV-2 transmission to patients with cancer should be prioritized to minimize impact on cancer treatments and maximize quality of life for individuals with cancer during the ongoing pandemic.


Assuntos
COVID-19 , Neoplasias , Vacinas , Feminino , Adulto , Masculino , Humanos , Pessoa de Meia-Idade , Vacinas contra COVID-19 , Glicoproteína da Espícula de Coronavírus , Estudos Transversais , Formação de Anticorpos , Qualidade de Vida , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2 , Neoplasias/epidemiologia , Anticorpos Antivirais , Atenção à Saúde
9.
Opt Express ; 20(7): 7323-37, 2012 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-22453413

RESUMO

We demonstrate two techniques to improve the quality of reconstructed optical projection tomography (OPT) images using the modulation transfer function (MTF) as a function of defocus experimentally determined from tilted knife-edge measurements. The first employs a 2-D binary filter based on the MTF frequency cut-off as an additional filter during back-projection reconstruction that restricts the high frequency information to the region around the focal plane and progressively decreases the spatial frequency bandwidth with defocus. This helps to suppress "streak" artifacts in OPT data acquired at reduced angular sampling, thereby facilitating faster OPT acquisitions. This method is shown to reduce the average background by approximately 72% for an NA of 0.09 and by approximately 38% for an NA of 0.07 compared to standard filtered back-projection. As a biological illustration, a Fli:GFP transgenic zebrafish embryo (3 days post-fertilisation) was imaged to demonstrate the improved imaging speed (a quarter of the acquisition time). The second method uses the MTF to produce an appropriate deconvolution filter that can be used to correct for the spatial frequency modulation applied by the imaging system.


Assuntos
Algoritmos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Tomografia Óptica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
Eur J Cancer ; 175: 1-10, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36084618

RESUMO

PURPOSE: People living with cancer and haematological malignancies are at an increased risk of hospitalisation and death following infection with acute respiratory syndrome coronavirus 2. Coronavirus third dose vaccine boosters are proposed to boost waning immune responses in immunocompromised individuals and increase coronavirus protection; however, their effectiveness has not yet been systematically evaluated. METHODS: This study is a population-scale real-world evaluation of the United Kingdom's third dose vaccine booster programme for cancer patients from 8th December 2020 to 7th December 2021. The cancer cohort comprises individuals from Public Health England's national cancer dataset, excluding individuals less than 18 years. A test-negative case-control design was used to assess the third dose booster vaccine effectiveness. Multivariable logistic regression models were fitted to compare risk in the cancer cohort relative to the general population. RESULTS: The cancer cohort comprised of 2,258,553 tests from 361,098 individuals. Third dose boosters were evaluated by reference to 87,039,743 polymerase chain reaction coronavirus tests. Vaccine effectiveness against breakthrough infections, symptomatic infections, coronavirus hospitalisation and death in cancer patients were 59.1%, 62.8%, 80.5% and 94.5%, respectively. Lower vaccine effectiveness was associated with a cancer diagnosis within 12 months, lymphoma, recent systemic anti-cancer therapy (SACT) or radiotherapy. Patients with lymphoma had low levels of protection from symptomatic disease. In spite of third dose boosters, following multivariable adjustment, individuals with cancer remain at an increased risk of coronavirus hospitalisation and death compared to the population control (OR 3.38, 3.01, respectively. p < 0.001 for both). CONCLUSIONS: Third dose boosters are effective for most individuals with cancer, increasing protection from coronavirus. However, their effectiveness is heterogenous and lower than the general population. Many patients with cancer will remain at the increased risk of coronavirus infections even after 3 doses. In the case of patients with lymphoma, there is a particularly strong disparity of vaccine effectiveness against breakthrough infection and severe disease. Breakthrough infections will disrupt cancer care and treatment with potentially adverse consequences on survival outcomes. The data support the role of vaccine boosters in preventing severe disease, and further pharmacological intervention to prevent transmission and aid viral clearance to limit the disruption of cancer care as the delivery of care continues to evolve during the coronavirus pandemic.


Assuntos
COVID-19 , Neoplasias , COVID-19/epidemiologia , COVID-19/prevenção & controle , Hospitalização , Humanos , Pandemias , Vacinação , Eficácia de Vacinas
11.
Haematologica ; 96(12): 1753-60, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21933862

RESUMO

BACKGROUND: Controversy persists regarding the role of Notch signaling in myelopoiesis. We have used genetic approaches, employing two Notch zebrafish mutants deadly seven (DES) and beamter (BEA) with disrupted function of notch1a and deltaC, respectively, and Notch1a morphants to analyze the development of leukocyte populations in embryonic and mature fish. DESIGN AND METHODS: Myelomonocytes were quantified in early embryos by in situ hybridization using a myeloper-oxidase (mpx) probe. Morpholinos were used to knock down expression of Notch1a or DeltaC. Wound healing assays and/or flow cytometry were used to quantify myelomonocytes in 5-day post-fertilization (dpf) Notch mutants (BEA and DES), morphants or pu.1:GFP, mpx:GFP and fms:RFP transgenic embryos. Flow cytometry was performed on 2-3 month old mutant fish. RESULTS: The number of mpx(+) cells in embryos was reduced at 48 hpf (but not at 26 hpf) in DES compared to WT. At 5 dpf this was reflected by a reduction in the number of myelomonocytic cells found at the wound site in mutants and in Notch1a morphants. This was due to a reduced number of myelomonocytes developing rather than a deficit in the migratory ability since transient inhibition of Notch signaling using DAPT had no effect. The early deficit in myelopoiesis was maintained into later life, 2-3 month old BEA and DES fish having a decreased proportion of myelomonocytes in both the hematopoietic organ (kidney marrow) and the periphery (coelomic cavity). CONCLUSIONS: Our results indicate that defects in Notch signaling affect definitive hematopoiesis, altering myelopoiesis from the early stages of development into the adult.


Assuntos
Embrião não Mamífero/embriologia , Proteínas de Homeodomínio/metabolismo , Mielopoese/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Receptor Notch1/metabolismo , Transdução de Sinais/fisiologia , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Animais , Embrião não Mamífero/citologia , Proteínas de Homeodomínio/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/genética , Organismos Geneticamente Modificados/embriologia , Organismos Geneticamente Modificados/genética , Receptor Notch1/genética , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
12.
Chemphyschem ; 12(3): 609-26, 2011 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-21337485

RESUMO

A fluorescence lifetime imaging (FLIM) technology platform intended to read out changes in Förster resonance energy transfer (FRET) efficiency is presented for the study of protein interactions across the drug-discovery pipeline. FLIM provides a robust, inherently ratiometric imaging modality for drug discovery that could allow the same sensor constructs to be translated from automated cell-based assays through small transparent organisms such as zebrafish to mammals. To this end, an automated FLIM multiwell-plate reader is described for high content analysis of fixed and live cells, tomographic FLIM in zebrafish and FLIM FRET of live cells via confocal endomicroscopy. For cell-based assays, an exemplar application reading out protein aggregation using FLIM FRET is presented, and the potential for multiple simultaneous FLIM (FRET) readouts in microscopy is illustrated.


Assuntos
Transferência Ressonante de Energia de Fluorescência/métodos , Proteínas/análise , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos , Corantes Fluorescentes/química , Proteínas de Fluorescência Verde/química , Humanos , Microscopia de Fluorescência , Ligação Proteica , Rodaminas/química , Produtos do Gene gag do Vírus da Imunodeficiência Humana/análise
13.
J R Soc Interface ; 14(132)2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28747399

RESUMO

Eph receptor and ephrin signalling has a major role in cell segregation and border formation, and may act through regulation of cell adhesion, repulsion or tension. To elucidate roles of cell repulsion and adhesion, we combined experiments in cell culture assays with quantitations of cell behaviour which are used in computer simulations. Cells expressing EphB2, or kinase-inactive EphB2 (kiEphB2), segregate and form a sharp border with ephrinB1-expressing cells, and this is disrupted by knockdown of N-cadherin. Measurements of contact inhibition of locomotion reveal that EphB2-, kiEphB2- and ephrinB1-expressing cells have strong heterotypic and weak homotypic repulsion. EphB2 cells have a transient increase in migration after heterotypic activation, which underlies a shift in the EphB2-ephrinB1 border but is not required for segregation or border sharpening. Simulations with the measured values of cell behaviour reveal that heterotypic repulsion can account for cell segregation and border sharpening, and is more efficient than decreased heterotypic adhesion. By suppressing homotypic repulsion, N-cadherin creates a sufficient difference between heterotypic and homotypic repulsion, and enables homotypic cohesion, both of which are required to sharpen borders.


Assuntos
Efrina-B1/metabolismo , Receptor EphB2/metabolismo , Movimento Celular , Efrina-B1/genética , Regulação da Expressão Gênica/fisiologia , Células HEK293 , Humanos , Receptor EphB2/genética
14.
Dev Comp Immunol ; 38(1): 187-92, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22561072

RESUMO

Nfil3, a transcription factor that has an array of functions in immune cells, has been described as key regulator of CD8α(+) dendritic cell and natural killer cell development in mice. In this report we show that Nfil3 is enriched in the myeloid compartment of adult zebrafish including eosinophils. Knockdown of Nfil3 in pu.1:GFP embryos resulted in a reduced number of myeloid cells as early as 24h post-fertilization, while erythropoiesis was unaffected. Using mpx and fms-fluorescent transgenic fish we found that all myeloid cell lineages, and in particular macrophages, had reduced numbers at 4days post-fertilization. This was reflected by less myeloid cells accumulating at a wound site. Pu.1, l-plastin, csf1r and mpx had reduced expression in Nfil3 morphants while runx1, gata1 and rag1 were unaffected. Collectively, these results describe a conserved expression pattern of Nfil3 in evolutionarily divergent species and indicate that Nfil3 is central to myeloid lineage commitment.


Assuntos
Mielopoese , Fatores de Transcrição/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo , Animais , Embrião não Mamífero/metabolismo , Morfolinos/metabolismo , Células Mieloides/metabolismo , Fatores de Transcrição/genética , Proteínas de Peixe-Zebra/genética
15.
Integr Biol (Camb) ; 4(3): 335-345, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22327539

RESUMO

In vivo studies allow us to investigate biological processes at the level of the organism. But not all aspects of in vivo systems are amenable to direct experimental measurements. In order to make the most of such data we therefore require statistical tools that allow us to obtain reliable estimates for e.g. kinetic in vivo parameters. Here we show how we can use approximate Bayesian computation approaches in order to analyse leukocyte migration in zebrafish embryos in response to injuries. We track individual leukocytes using live imaging following surgical injury to the embryos' tail-fins. The signalling gradient that leukocytes follow towards the site of the injury cannot be directly measured but we can estimate its shape and how it changes with time from the directly observed patterns of leukocyte migration. By coupling simple models of immune signalling and leukocyte migration with the unknown gradient shape into a single statistical framework we can gain detailed insights into the tissue-wide processes that are involved in the innate immune response to wound injury. In particular we find conclusive evidence for a temporally and spatially changing signalling gradient that modulates the changing activity of the leukocyte population in the embryos. We conclude with a robustness analysis which highlights the most important factors determining the leukocyte dynamics. Our approach relies only on the ability to simulate numerically the process under investigation and is therefore also applicable in other in vivo contexts and studies.


Assuntos
Leucócitos/fisiologia , Modelos Biológicos , Algoritmos , Animais , Teorema de Bayes , Movimento Celular/fisiologia , Humanos , Transdução de Sinais , Biologia de Sistemas , Imagem com Lapso de Tempo , Peixe-Zebra/embriologia , Peixe-Zebra/fisiologia
16.
Biomed Opt Express ; 2(5): 1340-50, 2011 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-21559145

RESUMO

We demonstrate the application of fluorescence lifetime optical projection tomography (FLIM-OPT) to in vivo imaging of lysC:GFP transgenic zebrafish embryos (Danio rerio). This method has been applied to unambiguously distinguish between the fluorescent protein (GFP) signal in myeloid cells from background autofluorescence based on the fluorescence lifetime. The combination of FLIM, an inherently ratiometric method, in conjunction with OPT results in a quantitative 3-D tomographic technique that could be used as a robust method for in vivo biological and pharmaceutical research, for example as a readout of Förster resonance energy transfer based interactions.

17.
Thromb Haemost ; 103(4): 797-807, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20174755

RESUMO

Low mass ambient exposure to airborne particles is associated with atherothrombotic events that may be a consequence of the combustion-derived nanoparticle content. There is concern also over the potential cardiovascular impact of manufactured nanoparticles. To better understand the mechanism by which toxic airborne particles can affect cardiovascular function we utilised zebrafish as a genetically tractable model. Using light and confocal fluorescence video-microscopy, we measured heart-rate and blood flow in the dorsal aorta and caudal artery of zebrafish larvae that had been exposed to a number of toxic and non-toxic microparticles and nanoparticles. Diesel exhaust particles (DEP), carboxy-charged Latex beads (carboxy-beads) and toxic alumina (Taimicron TM300), but not non-toxic alumina (Baikalox A125), were found to promote both skin and gut cell damage, increased leukocyte invasion into the epidermis, tail muscle ischaemia and haemostasis within the caudal artery of free swimming zebrafish larvae. The presence of sodium sulfite, a reducing agent, or warfarin, an anticoagulant, within the system water abrogated the effects of both toxic alumina and carboxy-beads but not DEP. Genetic manipulation of skin barrier function augmented skin damage and haemostasis, even for the non-toxic alumina. The toxic effects of carboxy-beads were still apparent after leukocyte numbers were depleted with anti-Pu.1 morpholino. We conclude that particle uptake across skin epithelium and gut mucosal barriers, or the presence of leukocytes, is not required for particle-induced haemostasis while a compromised skin barrier function accentuated tissue injury and haemostasis.


Assuntos
Células Epiteliais/metabolismo , Hemostasia/efeitos dos fármacos , Microesferas , Nanopartículas , Material Particulado/toxicidade , Absorção Cutânea , Pele/metabolismo , Peixe-Zebra/sangue , Óxido de Alumínio/toxicidade , Animais , Anticoagulantes/farmacologia , Antioxidantes/farmacologia , Débito Cardíaco/efeitos dos fármacos , Trato Gastrointestinal/metabolismo , Frequência Cardíaca/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/metabolismo , Látex/toxicidade , Leucócitos/efeitos dos fármacos , Microscopia de Fluorescência , Microscopia de Vídeo , Mucosa/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Material Particulado/metabolismo , Permeabilidade , Fluxo Sanguíneo Regional/efeitos dos fármacos , Pele/embriologia , Absorção Cutânea/genética , Sulfitos/farmacologia , Fatores de Tempo , Emissões de Veículos/toxicidade , Varfarina/farmacologia , Peixe-Zebra/embriologia , Peixe-Zebra/genética
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