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1.
EMBO Rep ; 21(11): e51819, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33155436

RESUMO

Social media has been an effective vector for spreading disinformation about medicine and science. Informational hygiene can reduce the severity of falsehoods about health.


Assuntos
COVID-19 , Mídias Sociais , Humanos , Higiene
2.
EMBO Rep ; 20(8): e48706, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286661

RESUMO

Journalistic impartiality is a laudable aim, but overly rigid application of unbiased reporting may do more harm than good. The issue of false balance in science reporting has severe consequences for health and the environment.


Assuntos
Meios de Comunicação de Massa/ética , Política , Viés , Humanos
3.
Br J Cancer ; 123(10): 1562-1569, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32848201

RESUMO

BACKGROUND: Tumour hypoxia is associated with metastatic disease, and while there have been many mechanisms proposed for why tumour hypoxia is associated with metastatic disease, it remains unclear whether one precise mechanism is the key reason or several in concert. Somatic evolution drives cancer progression and treatment resistance, fuelled not only by genetic and epigenetic mutation but also by selection from interactions between tumour cells, normal cells and physical micro-environment. Ecological habitats influence evolutionary dynamics, but the impact on tempo of evolution is less clear. METHODS: We explored this complex dialogue with a combined clinical-theoretical approach by simulating a proliferative hierarchy under heterogeneous oxygen availability with an agent-based model. Predictions were compared against histology samples taken from glioblastoma patients, stained to elucidate areas of necrosis and TP53 expression heterogeneity. RESULTS: Results indicate that cell division in hypoxic environments is effectively upregulated, with low-oxygen niches providing avenues for tumour cells to spread. Analysis of human data indicates that cell division is not decreased under hypoxia, consistent with our results. CONCLUSIONS: Our results suggest that hypoxia could be a crucible that effectively warps evolutionary velocity, making key mutations more likely. Thus, key tumour ecological niches such as hypoxic regions may alter the evolutionary tempo, driving mutations fuelling tumour heterogeneity.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Evolução Clonal/fisiologia , Glioblastoma/genética , Glioblastoma/patologia , Hipóxia Tumoral/fisiologia , Algoritmos , Neoplasias Encefálicas/metabolismo , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Biologia Computacional/métodos , Progressão da Doença , Glioblastoma/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Sequenciamento de Nucleotídeos em Larga Escala/estatística & dados numéricos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Modelos Teóricos , Metástase Neoplásica , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Oxigênio/metabolismo , Fatores de Tempo
4.
Bull Math Biol ; 82(2): 20, 2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31970500

RESUMO

Cancer is a complex phenomenon, and the sheer variation in behaviour across different types renders it difficult to ascertain underlying biological mechanisms. Experimental approaches frequently yield conflicting results for myriad reasons, and mathematical modelling of cancer is a vital tool to explore what we cannot readily measure, and ultimately improve treatment and prognosis. Like experiments, models are underpinned by certain biological assumptions, variation of which can lead to divergent predictions. An outstanding and important question concerns contact inhibition of proliferation (CIP), the observation that proliferation ceases when cells are spatially confined by their neighbours. CIP is a characteristic of many healthy adult tissues, but it remains unclear to which extent it holds in solid tumours, which exhibit regions of hyper-proliferation, and apparent breakdown of CIP. What precisely occurs in tumour tissue remains an open question, which mathematical modelling can help shed light on. In this perspective piece, we explore the implications of different hypotheses and available experimental evidence to elucidate the implications of these scenarios. We also outline how erroneous conclusions about the nature of tumour growth may be arrived at by looking selectively at biological data in isolation, and how this might be circumvented.


Assuntos
Modelos Biológicos , Neoplasias/patologia , Animais , Agregação Celular/fisiologia , Proliferação de Células/fisiologia , Simulação por Computador , Inibição de Contato/fisiologia , Humanos , Conceitos Matemáticos , Neoplasias/fisiopatologia , Esferoides Celulares/patologia , Células Tumorais Cultivadas
6.
Child Dev ; 89(1): 141-147, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29266222

RESUMO

Exposure to nonionizing radiation used in wireless communication remains a contentious topic in the public mind-while the overwhelming scientific evidence to date suggests that microwave and radio frequencies used in modern communications are safe, public apprehension remains considerable. A recent article in Child Development has caused concern by alleging a causative connection between nonionizing radiation and a host of conditions, including autism and cancer. This commentary outlines why these claims are devoid of merit, and why they should not have been given a scientific veneer of legitimacy. The commentary also outlines some hallmarks of potentially dubious science, with the hope that authors, reviewers, and editors might be better able to avoid suspect scientific claims.


Assuntos
Tratamento por Radiofrequência Pulsada , Tecnologia sem Fio , Criança , Desenvolvimento Infantil , Campos Eletromagnéticos , Humanos , Ondas de Rádio
8.
Adv Exp Med Biol ; 996: 349-360, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29124714

RESUMO

Ultraviolet light has long been used to alleviate a number of skin conditions, and its efficacy is well known. However, over-exposure to ultraviolet radiation has a number of detrimental effects and thus it is vital to maintain a dose to skin within the therapeutic window. To maximise treatment gain whilst circumventing potential side-effects of over-exposure requires accurate determination of irradiance and skin-dose. This is complicated by the fact that ultraviolet radiation is essentially absorbed at the skin surface, which means that changing orientation of the patient and source can modulate dose received. In addition, irregular patient shapes mean dose must be carefully calibrated. This chapter focuses on methods of determination of dose, clinical protocols for quantifying radiation dose received and mathematical models for estimating these quantities.


Assuntos
Doses de Radiação , Dermatopatias/radioterapia , Pele/efeitos da radiação , Raios Ultravioleta , Terapia Ultravioleta/métodos , Relação Dose-Resposta à Radiação , Humanos , Dosímetros de Radiação , Exposição à Radiação , Lesões por Radiação/etiologia , Lesões por Radiação/prevenção & controle , Monitoramento de Radiação/instrumentação , Proteção Radiológica , Fatores de Risco , Pele/patologia , Dermatopatias/diagnóstico , Raios Ultravioleta/efeitos adversos , Terapia Ultravioleta/efeitos adversos
9.
Adv Exp Med Biol ; 899: 167-96, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27325267

RESUMO

Regions of hypoxia in tumours can be modelled in vitro in 2D cell cultures with a hypoxic chamber or incubator in which oxygen levels can be regulated. Although this system is useful in many respects, it disregards the additional physiological gradients of the hypoxic microenvironment, which result in reduced nutrients and more acidic pH. Another approach to hypoxia modelling is to use three-dimensional spheroid cultures. In spheroids, the physiological gradients of the hypoxic tumour microenvironment can be inexpensively modelled and explored. In addition, spheroids offer the advantage of more representative modelling of tumour therapy responses compared with 2D culture. Here, we review the use of spheroids in hypoxia tumour biology research and highlight the different methodologies for spheroid formation and how to obtain uniformity. We explore the challenge of spheroid analyses and how to determine the effect on the hypoxic versus normoxic components of spheroids. We discuss the use of high-throughput analyses in hypoxia screening of spheroids. Furthermore, we examine the use of mathematical modelling of spheroids to understand more fully the hypoxic tumour microenvironment.


Assuntos
Modelos Biológicos , Esferoides Celulares/patologia , Hipóxia Tumoral , Biomarcadores Tumorais/metabolismo , Humanos , Imuno-Histoquímica , Consumo de Oxigênio
10.
Elife ; 132024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38284745

RESUMO

In biomedical science, it is a reality that many published results do not withstand deeper investigation, and there is growing concern over a replicability crisis in science. Recently, Ellipse of Insignificance (EOI) analysis was introduced as a tool to allow researchers to gauge the robustness of reported results in dichotomous outcome design trials, giving precise deterministic values for the degree of miscoding between events and non-events tolerable simultaneously in both control and experimental arms (Grimes, 2022). While this is useful for situations where potential miscoding might transpire, it does not account for situations where apparently significant findings might result from accidental or deliberate data redaction in either the control or experimental arms of an experiment, or from missing data or systematic redaction. To address these scenarios, we introduce Region of Attainable Redaction (ROAR), a tool that extends EOI analysis to account for situations of potential data redaction. This produces a bounded cubic curve rather than an ellipse, and we outline how this can be used to identify potential redaction through an approach analogous to EOI. Applications are illustrated, and source code, including a web-based implementation that performs EOI and ROAR analysis in tandem for dichotomous outcome trials is provided.


Assuntos
Publicações , Projetos de Pesquisa
11.
R Soc Open Sci ; 11(1): 231056, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38298396

RESUMO

The reality that volumes of published biomedical research are not reproducible is an increasingly recognized problem. Spurious results reduce trustworthiness of reported science, increasing research waste. While science should be self-correcting from a philosophical perspective, that in insolation yields no information on efforts required to nullify suspect findings or factors shaping how quickly science may be corrected. There is also a paucity of information on how perverse incentives in the publishing ecosystem favouring novel positive findings over null results shape the ability of published science to self-correct. Knowledge of factors shaping self-correction of science remain obscure, limiting our ability to mitigate harms. This modelling study introduces a simple model to capture dynamics of the publication ecosystem, exploring factors influencing research waste, trustworthiness, corrective effort and time to correction. Results from this work indicate that research waste and corrective effort are highly dependent on field-specific false positive rates and time delays to corrective results to spurious findings are propagated. The model also suggests conditions under which biomedical science is self-correcting and those under which publication of correctives alone cannot stem propagation of untrustworthy results. Finally, this work models a variety of potential mitigation strategies, including researcher- and publisher-driven interventions.

12.
BMJ Open ; 14(2): e078551, 2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38309749

RESUMO

OBJECTIVE: Cervical screening is a life-saving intervention, which reduces the incidence of and mortality from cervical cancer in the population. Human papillomavirus (HPV) based screening modalities hold unique promise in improving screening accuracy. HPV prevalence varies markedly by age, as does resultant cervical intraepithelial neoplasia (CIN), with higher rates recorded in younger women. With the advent of effective vaccination for HPV drastically reducing prevalence of both HPV and CIN, it is critical to model how the accuracy of different screening approaches varies with age cohort and vaccination status. This work establishes a model for the age-specific prevalence of HPV factoring in vaccine coverage and predicts how the accuracy of common screening modalities is affected by age profile and vaccine uptake. DESIGN: Modelling study of HPV infection rates by age, ascertained from European cohorts prior to the introduction of vaccination. Reductions in HPV due to vaccination were estimated from the bounds predicted from multiple modelling studies, yielding a model for age-varying HPV and CIN grades 2 and above (CIN2+) prevalence. SETTING: Performance of both conventional liquid-based cytology (LBC) screening and HPV screening with LBC reflex (HPV reflex) was estimated under different simulated age cohorts and vaccination levels. PARTICIPANTS: Simulated populations of varying age and vaccination status. RESULTS: HPV-reflex modalities consistently result in much lower incidence of false positives than LBC testing, with an accuracy that improves even as HPV and CIN2+ rates decline. CONCLUSIONS: HPV-reflex tests outperform LBC tests across all age profiles, resulting in greater test accuracy. This improvement is especially pronounced as HPV infection rates fall and suggests HPV-reflex modalities are robust to future changes in the epidemiology of HPV.


Assuntos
Infecções por Papillomavirus , Vacinas contra Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle , Papillomavirus Humano , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/prevenção & controle , Prevalência , Detecção Precoce de Câncer/métodos , Displasia do Colo do Útero/diagnóstico , Programas de Rastreamento , Vacinação
13.
Sci Rep ; 14(1): 7218, 2024 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538658

RESUMO

The Y-box binding protein-1 (YBX1) gene codes for a multifunctional oncoprotein that is increasingly being linked to the regulations of many aspects of cancer cell biology. Disparities in treatment outcomes between male and female cancer patients are increasingly reported. This study aimed to examine the relationship between YBX1 expression and overall survival in male and female patients with solid tumours. Overall survival and YBX1 expression data for cohorts of male and female cancer patients obtained from freely available databases were analysed with a cox proportional hazard model with covariates of biological sex and YBX1 expression. Kaplan-Meier curves and Violin plots were constructed for segregated male and female cohorts. High YBX1 expression was significantly associated with poor survival in 2 female-only and 4 mixed-sex cancer sites. In female lung cancer patients, better survival and lower YBX1 expression were identified. The clinical importance of YBX1 expression in cancer ought to be evaluated in a sex-specific manner, especially in lung cancer.


Assuntos
Neoplasias Pulmonares , Humanos , Masculino , Feminino , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Proteína 1 de Ligação a Y-Box/genética , Proteína 1 de Ligação a Y-Box/metabolismo , Regulação Neoplásica da Expressão Gênica , Proliferação de Células
14.
HRB Open Res ; 7: 36, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39355144

RESUMO

Background: Scientific publications have been growing exponentially, contributing to an oversaturated information environment. Quantifying a research output's impact and reach cannot be solely measured by traditional metrics like citation counts as these have a lag time and are largely focused on an academic audience. There is increasing recognition to consider 'alternative metrics' or altmetrics to measure more immediate and broader impacts of research. Better understanding of altmetrics can help researchers better navigate evolving information environments and changing appetites for different types of research. Objectives: Our study aims to: 1) analyse the amount and medium of Altmetric coverage of health research produced by Irish organisations (2017 - 2023), identifying changes over time and 2) investigate differences in the amount of coverage between clinical areas (e.g., nutrition vs. neurology). Methods: Using Altmetric institutional access, we will gather data on research outputs published 1 January 2017 through 31 December 2023 from active Irish organisations with Research Organisation Registry (ROR) IDs. Outputs will be deduplicated and stratified by their Australian and New Zealand Standard Research Classification relating to ≥1 field of health research: Biological Sciences, Biomedical and Clinical Sciences, Chemical Sciences, Health Sciences, and Psychology. We will clean data using R and perform descriptive analyses, establishing counts and frequencies of coverage by clinical area and medium (e.g., traditional news, X, etc.); data will be plotted on a yearly and quarterly basis where appropriate. Results and Conclusions: Improved understanding of one's information environment can help researchers better navigate their local landscapes and identify pathways for more effective communication to the public. All R code will be made available open-source, allowing researchers to adapt it to evaluate their local landscapes.

15.
PEC Innov ; 5: 100311, 2024 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-39027229

RESUMO

Objective: The overabundance of health misinformation has undermined people's capacity to make evidence-based, informed choices about their health. Using the Informed Health Choices (IHC) Key Concepts (KCs), we are developing a two-stage education programme, Informed Health Choices-Cancer (IHC-C), to provide those impacted by cancer with the knowledge and skills necessary to think critically about the reliability of health information and claims and make well-informed choices. Stage 1 seeks to prioritise the most relevant Key Concepts. Methods: A project group and a patient and carer participation group completed a two-round prioritisation process. The process involved disseminating pre-reading materials, training sessions, and a structured judgement form to evaluate concepts for inclusion. Data from each round were analysed to reach a consensus on the concepts to include. Results: Fourteen participants were recruited and completed the first-round prioritisation. Fifteen participants undertook the second-round prioritisation. Nine Key Concepts were selected for the programme across five training sessions and two consensus meetings. Conclusion: The prioritised concepts identified represent the most pertinent aspects of cancer-related information for those impacted by the disease. By incorporating these concepts into educational materials and communication strategies, healthcare providers and organisations can potentially help cancer patients, survivors, and their loved ones to recognise and combat cancer-related misinformation more effectively. Innovation: This study introduces a participatory prioritisation process, which integrates the expertise of healthcare professionals with the insights of patients and carers, thereby enhancing the programme's relevance and applicability.

16.
Med Phys ; 39(6): 3019-25, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22755686

RESUMO

PURPOSE: UVR phototherapy cabins exist in a huge variety of configurations and geometries. An accurate dose model has been developed which can be used to examine the question of cabin design to investigate factors influencing dose on a patient. METHODS: This work extends the existing dose model to entire cabins and investigates how cabin and reflector geometry influence resultant dose. RESULTS: The model predictions are in line with what is measured. It is found that the length and angle of the reflectors have a large influence on received dose. CONCLUSIONS: The influence of cabin geometry is important in estimating patient dose, and the findings of this work are applicable to future cabin designs.


Assuntos
Terapia Ultravioleta/métodos , Desenho de Equipamento , Humanos , Dosagem Radioterapêutica , Terapia Ultravioleta/instrumentação
17.
BMJ Evid Based Med ; 27(6): 319-323, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-34933928

RESUMO

Vaccination is a life-saving endeavour, yet risk and uncertainty are unavoidable in science and medicine. Vaccination remains contentious in the public mind, and vaccine hesitancy is a serious public health issue. This has recently been reignited in the discussion over potential side effects of COVID-19 vaccines, and the decision by several countries to suspend measures such as the AstraZeneca vaccine. In these instances, the precautionary principle has often been invoked as a rationale, yet such heuristics do not adequately weigh potential harms against real benefits. How we analyse, communicate and react to potential harms is absolutely paramount to ensure the best decisions and outcomes for societal health, and maintaining public confidence. While balancing benefits and risks is an essential undertaking, it cannot be achieved without due consideration of several other pertinent factors, especially in the context of vaccination, where misguided or exaggerated fears have in the past imperilled public health. While well meaning, over reactions to potential hazards of vaccination and other health interventions can have unintended consequences, and cause lingering damage to public trust. In this analysis, we explore the challenges of assessing risk and benefit, and the limitations of the precautionary principle in these endeavours. When risk is unclear, cautious vigilance might be a more pragmatic and useful policy than reactionary suspensions.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Vacinas contra COVID-19/efeitos adversos , COVID-19/prevenção & controle , Saúde Pública , Vacinação/efeitos adversos , Incerteza
18.
Elife ; 112022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36125120

RESUMO

There is increasing awareness throughout biomedical science that many results do not withstand the trials of repeat investigation. The growing abundance of medical literature has only increased the urgent need for tools to gauge the robustness and trustworthiness of published science. Dichotomous outcome designs are vital in randomized clinical trials, cohort studies, and observational data for ascertaining differences between experimental and control arms. It has however been shown with tools like the fragility index (FI) that many ostensibly impactful results fail to materialize when even small numbers of patients or subjects in either the control or experimental arms are recoded from event to non-event. Critics of this metric counter that there is no objective means to determine a meaningful FI. As currently used, FI is not multidimensional and is computationally expensive. In this work, a conceptually similar geometrical approach is introduced, the ellipse of insignificance. This method yields precise deterministic values for the degree of manipulation or miscoding that can be tolerated simultaneously in both control and experimental arms, allowing for the derivation of objective measures of experimental robustness. More than this, the tool is intimately connected with sensitivity and specificity of the event/non-event tests, and is readily combined with knowledge of test parameters to reject unsound results. The method is outlined here, with illustrative clinical examples.


Science and medicine are vital to the well-being of humankind. Yet for all the incredible advances science has made, the unfortunate reality is that a worrying fraction of biological research is not reliable. Erroneous results might arise by chance or because of scientists' mistakes or ineptitude. Very occasionally, researchers may behave unethically and fabricate or inappropriately manipulate their data. Inevitably, this can lead to untrustworthy research that misleads scientists and the public on questions integral to our health. Indeed, a recent study showed the results of several high-profile cancer papers could not be fully replicated. This problem is not unique to cancer, and studies on various other diseases have also not stood up to scrutiny from outside investigators. Finding ways to detect dubious results is therefore essential to protect the public's well-being and maintain public trust in science. Here, Grimes demonstrates a new tool called the 'Ellipse of Insignificance' for measuring the reliability of dichotomous studies which are commonly used in many branches of biomedical sciences, including clinical trials. These studies typically compare two groups: one which was subjected to a specific treatment, and a control group which was not. Statistical methods are then applied to estimate how likely it is that differences in the number of observed events between the groups are real or due to chance. The tool created by Grimes explores what would happen to seemingly strong results if some of the events in both the control and experimental arm of the study are recoded. It then assesses how much nudging is needed to change the statistical outcome of the experiment: the more interventions the result can withstand, the more robust the experiment. Grimes tested the tool and showed that a study suggesting a link between miscarriage and magnetic field exposure was likely unreliable because shifting the outcomes of less than two participants would change the result. Scientists could use the Ellipse of Insignificance tool to quickly identify misleading published results or potential research fraud. Doing this could benefit researchers and protect the public from potential harm. It may also help preserve research integrity, increase transparency, and bolster public trust in science.


Assuntos
Projetos de Pesquisa , Humanos , Ensaios Clínicos como Assunto
19.
JAMA Oncol ; 8(3): 456-461, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34882171

RESUMO

IMPORTANCE: Concerns over radiofrequency radiation (RFR) and carcinogenesis have long existed, and the advent of 5G mobile technology has seen a deluge of claims asserting that the new standard and RFR in general may be carcinogenic. For clinicians and researchers in the field, it is critical to address patient concerns on the topic and to be familiar with the existent evidence base. OBSERVATIONS: This review considers potential biophysical mechanisms of cancer induction, elucidating mechanisms of electromagnetically induced DNA damage and placing RFR in appropriate context on the electromagnetic spectrum. The existent epidemiological evidence in humans and laboratory animals to date on the topic is also reviewed and discussed. CONCLUSIONS AND RELEVANCE: The evidence from these combined strands strongly indicates that claims of an RFR-cancer link are not supported by the current evidence base. Much of the research to date, however, has been undermined by methodological shortcomings, and there is a need for higher-quality future research endeavors. Finally, the role of fringe science and unsubstantiated claims in patient and public perception on this topic is highly relevant and must be carefully considered.


Assuntos
Carcinogênese , Ondas de Rádio , Animais , Humanos , Ondas de Rádio/efeitos adversos
20.
Cancer Discov ; 12(1): 26-30, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34930788

RESUMO

Cancer misinformation has become an increasingly prevalent problem, imperiling public health and understanding. Cancer researchers and clinicians must play a significant role in combating its detrimental consequences.


Assuntos
COVID-19 , Comunicação , Medicina Baseada em Evidências , Neoplasias , SARS-CoV-2 , Mídias Sociais , Humanos
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