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1.
Pediatr Blood Cancer ; : e31253, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39126369

RESUMO

BACKGROUND: Many studies highlight poor health-related quality of life (HRQoL) in children treated for brain tumours and their parents. However, little is known about the extent to which their informational, healthcare and communication needs regarding HRQoL are met during medical outpatient consultations. AIM: To explore the experiences of families regarding communication with physicians about HRQoL issues during consultations after treatment for childhood brain tumours. METHODS: Interviews were conducted with 18 families of children and adolescents aged 8-17 years after completion of brain tumour treatment. Participants had completed treatment within the last 5 years and were receiving regular outpatient follow-up care. Thematic analysis was undertaken using the Framework Method. RESULTS: Five main themes were identified: (i) unmet emotional and mental health needs; (ii) double protection; (iii) unmet information needs; (iv) communication barriers within consultations; and (v) finding a new normal. CONCLUSION: There was a need to improve communication between clinicians and these families, improve information provision, and overcome barriers to conversing with children within these outpatient consultations. Children and their parents should be supported to voice their current needs and concerns regarding their HRQoL. These findings will inform further development of the UK version of the 'KLIK' patient- and parent-reported outcome (PROM) portal.

2.
Addit Manuf ; 842024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38567361

RESUMO

The working curve informs resin properties and print parameters for stereolithography, digital light processing, and other photopolymer additive manufacturing (PAM) technologies. First demonstrated in 1992, the working curve measurement of cure depth vs radiant exposure of light is now a foundational measurement in the field of PAM. Despite its widespread use in industry and academia, there is no formal method or procedure for performing the working curve measurement, raising questions about the utility of reported working curve parameters. Here, an interlaboratory study (ILS) is described in which 24 individual laboratories performed a working curve measurement on an aliquot from a single batch of PAM resin. The ILS reveals that there is enormous scatter in the working curve data and the key fit parameters derived from it. The measured depth of light penetration Dp varied by as much as 7x between participants, while the critical radiant exposure for gelation Ec varied by as much as 70x. This significant scatter is attributed to a lack of common procedure, variation in light engines, epistemic uncertainties from the Jacobs equation, and the use of measurement tools with insufficient precision. The ILS findings highlight an urgent need for procedural standardization and better hardware characterization in this rapidly growing field.

3.
Front Pediatr ; 11: 1038937, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37033188

RESUMO

Optic pathway and hypothalamic glioma (OPHG) are low-grade brain tumors that arise from any part of the visual pathways frequently involving the hypothalamus. The tumors grow slowly and present with features driven by their precise anatomical site, their age at presentation and the stage of growth and development of the host neural and orbital bony tissues. Up to 50% of optic pathway glioma arise in association with Neurofibromatosis type 1 (NF1), which affects 1 in 3,000 births and is a cancer predisposition syndrome. As low-grade tumors, they almost never transform to malignant glioma yet they can threaten life when they present under two years of age. The main risks are to threaten vision loss by progressive tumor damage to optic pathways; furthermore, invasion of the hypothalamus can lead to diencephalic syndrome in infancy and hypopituitarism later in life. Progressive cognitive and behavioural dysfunction can occur, as part of NF1 syndromic features and in sporadic cases where large bulky tumors compress adjacent structures and disrupt neuro-hypothalamic pathways. Persistently progressive tumors require repeated treatments to attempt to control vision loss, other focal brain injury or endocrine dysfunction. In contrast tumors presenting later in childhood can be seen to spontaneously arrest in growth and subsequently progress after periods of stability. These patterns are influenced by NF status as well as stages of growth and development of host tissues. The past two decades has seen an expansion in our understanding and knowledge of the clinical and scientific features of these tumors, their modes of presentation, the need for careful visual and endocrine assessment. This influences the decision-making surrounding clinical management with surgery, radiotherapy, chemotherapy and most recently, the potential benefit of molecularly targeted drug therapy. This article, based upon the authors' clinical and research experience and the published literature will highlight advances in approach to diagnosis, the established role of vision loss as justification of treatments and the emerging evidence of endocrine and neurological consequences that need to be incorporated into judgements for case selection for therapy or observation. Consideration is given to the current state of biological evidence justifying current trials of new therapies, the genetic studies of the NF1 gene and the potential for new approaches to OPHG detection and treatment. The outstanding health system priorities from the perspective of children, their parents and health system commissioners or insurers are discussed.

4.
Cancers (Basel) ; 15(3)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36765816

RESUMO

Brain and spinal tumors affect 1 in 1000 people by 25 years of age, and have diverse histological, biological, anatomical and dissemination characteristics. A mortality of 30-40% means the majority are cured, although two-thirds have life-long disability, linked to accumulated brain injury that is acquired prior to diagnosis, and after surgery or chemo-radiotherapy. Only four drugs have been licensed globally for brain tumors in 40 years and only one for children. Most new cancer drugs in clinical trials do not cross the blood-brain barrier (BBB). Techniques to enhance brain tumor drug delivery are explored in this review, and cover those that augment penetration of the BBB, and those that bypass the BBB. Developing appropriate delivery techniques could improve patient outcomes by ensuring efficacious drug exposure to tumors (including those that are drug-resistant), reducing systemic toxicities and targeting leptomeningeal metastases. Together, this drug delivery strategy seeks to enhance the efficacy of new drugs and enable re-evaluation of existing drugs that might have previously failed because of inadequate delivery. A literature review of repurposed drugs is reported, and a range of preclinical brain tumor models available for translational development are explored.

5.
Front Oncol ; 12: 982914, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36267979
6.
Med Leg J ; 90(4): 182-188, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36138565

RESUMO

We write as experienced paediatric practitioners who have been involved in medico-legal proceedings where cases related to childhood cancer practice have featured frequently. We will use the service evaluation of Professor David A Walker's last 35 cases, where all but seven concerned children with tumours of the brain or spine to illustrate the concerns that families raise. We refer to the evidence from the HeadSmart programme (www.headsmart.org.uk), which seeks to accelerate diagnosis by raising awareness of the disease and symptoms. We use the experience of Dr Jonathan AG Punt to illustrate the legal issues that apply and explain the way that significant quantum calculations are applied to cases of this type. The current move by NHS Resolution to explore the expanded role of mediation will be discussed and the need for research to explore the precise way that mediation could be developed to offer an alternative approach to conflict resolution.


Assuntos
Neoplasias , Criança , Humanos , Negociação , Inquéritos e Questionários
7.
Radiol Technol ; 93(3): 255-267, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35017269

RESUMO

PURPOSE: The purpose of the study was to examine mean differences between intrapersonal and institutional variables and the overall perception of radiation safety (OPRS) among U.S. radiologic technologists. The study also sought to demonstrate the applicability of the socioecological model for radiation safety decision-making. METHODS: A quantitative, cross-sectional design with the Radiation Actions and Dimensions of Radiation Safety survey instrument was used to collect data and guide hypotheses testing. The 425 research participants included radiologic technologists working in radiography, mammography, computed tomography, and radiology management. Categorical and descriptive data were calculated, and 1-way analysis of variance tests were used to analyze hypotheses. RESULTS: Seven main effects demonstrated mean differences between groups for the OPRS, including age (F5,419 = 2.55, P = .03), years of experience (F5,419 = 4.27, P = .001), primary employed imaging modality (F2,422 = 9.04, P < .001), primary role (F2,422 = 4.58, P = .01), shift length (F3,421 = 10.33, P < .001), primary practice facility (F4,404 = 5.00, P = .001), and work shift (F3,405 = 4.14, P = .007), with shift length having the largest effect. Level of education, employment status, number of imaging credentials, gender, patient population, and practice location were not significant at the level of P ≤ .05. DISCUSSION: Radiation safety culture is a multidimensional topic that requires consideration of several intervening influences, making the socioecological model well aligned when considering radiation safety culture and radiation safety perception in medical imaging. Previous research on radiation safety perception among radiologic technologists demonstrated that leadership actions, teamwork across imaging stakeholders, organizational learning, and questioning behavior are drivers of OPRS. However, this study's findings demonstrate that radiologic technologist scheduling practices and primary employed imaging modalities also should be considered when seeking to improve OPRS. CONCLUSION: This study presents an extensive examination of intrapersonal and institutional variables on OPRS among U.S.-based radiologic technologists and provides findings to support radiation safety culture decision-making in medical imaging, particularly for shift length considerations.


Assuntos
Gestão da Segurança , Tecnologia Radiológica , Estudos Transversais , Humanos , Percepção , Inquéritos e Questionários , Tecnologia Radiológica/educação
8.
SN Soc Sci ; 2(1): 1, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34934956

RESUMO

The present study examined the 2015 Trends in international mathematics and science study "Advanced" data to examine how both the type of homework assigned and how that homework was used were related to advanced mathematics achievement and attitudes toward advanced mathematics among 12th grade students in the USA. Additionally, students' use of the internet was examined as a predictor of these outcomes. Results showed that the use of homework assignments that required students to find one or more applications of the content covered in class was a statistically significant positive predictor of both Students like learning advanced mathematics and students value advanced mathematics, while discussing homework in class was a significant, negative predictor of Students like learning advanced mathematics. Additionally, using the internet to discuss math topics with other students and to find information was significantly, positively associated with both attitudinal outcomes. Using the internet to communicate with the teacher was positively associated with Students like learning advanced mathematics scores.

9.
Small ; 17(28): e2100662, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34110664

RESUMO

The development of a massively parallel lithographic technique called electrochemical polymer pen lithography is reported. Pyramidal pen arrays, consisting of more than 10 000 hydrogel pens loaded with metal salts, are integrated into a three-electrode cell and used to locally reduce ions at each pen tip. This system enables high-throughput patterning of a variety of metallic inks (e.g., Ni2+ , Pt2+ , Ag+ ) on the nanometer to micrometer length scale. By incorporating a z-direction piezo actuator, the extension length and dwell time can be used to precisely define feature dimensions (210 to 10 µm in width, and up to 900 nm in height, thus far). Furthermore, by controlling the potential and precursor concentrations, more than one element can be simultaneously deposited, creating a new tool for the synthesis of alloy features, such as NiCo, which are relevant for catalysis. Importantly, this methodology enables fine control over feature size and composition in a single pattern, which may make it ultimately useful for rapid, high-throughput combinatorial screening of metallic features.


Assuntos
Nanotecnologia , Polímeros , Catálise , Tinta , Impressão
10.
Br J Gen Pract ; 71(705): 151-152, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33619048
11.
J Appl Stat ; 48(16): 3208-3219, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35707262

RESUMO

This study introduces a coefficient of discrimination for use with nominal and ordinal regression models. Computation of the coefficient is demonstrated with data from the Pew Research Center's 25th Anniversary of the Web Omnibus Survey pertaining to cell/home phone ownership, where the coefficient of discrimination indicates that respondent age and gender increased the probability of a correct versus incorrect classification by 13.9%. Additionally, the coefficient is compared to existing coefficients.

12.
Neuro Oncol ; 23(1): 100-111, 2021 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-32628746

RESUMO

BACKGROUND: The aim of the project was to identify risk factors associated with visual progression and treatment indications in pediatric patients with neurofibromatosis type 1 associated optic pathway glioma (NF1-OPG). METHODS: A multidisciplinary expert group consisting of ophthalmologists, pediatric neuro-oncologists, neurofibromatosis specialists, and neuro-radiologists involved in therapy trials assembled a cohort of children with NF1-OPG from 6 European countries with complete clinical, imaging, and visual outcome datasets. Using methods developed during a consensus workshop, visual and imaging data were reviewed by the expert team and analyzed to identify associations between factors at diagnosis with visual and imaging outcomes. RESULTS: Eighty-three patients (37 males, 46 females, mean age 5.1 ±â€…2.6 y; 1-13.1 y) registered in the European treatment trial SIOP LGG-2004 (recruited 2004-2012) were included. They were either observed or treated (at diagnosis/after follow-up).In multivariable analysis, factors present at diagnosis associated with adverse visual outcomes included: multiple visual signs and symptoms (adjusted odds ratio [adjOR]: 8.33; 95% CI: 1.9-36.45), abnormal visual behavior (adjOR: 4.15; 95% CI: 1.20-14.34), new onset of visual symptoms (adjOR: 4.04; 95% CI: 1.26-12.95), and optic atrophy (adjOR: 3.73; 95% CI: 1.13-12.53). Squint, posterior visual pathway tumor involvement, and bilateral pathway tumor involvement showed borderline significance. Treatment appeared to reduce tumor size but improved vision in only 10/45 treated patients. Children with visual deterioration after primary observation are more likely to improve with treatment than children treated at diagnosis. CONCLUSIONS: The analysis identified the importance of symptomatology, optic atrophy, and history of vision loss as predictive factors for poor visual outcomes in children with NF1-OPG.


Assuntos
Neurofibromatose 1 , Glioma do Nervo Óptico , Criança , Pré-Escolar , Estudos de Coortes , Europa (Continente) , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Neurofibromatose 1/complicações , Neurofibromatose 1/epidemiologia , Neurofibromatose 1/terapia , Glioma do Nervo Óptico/complicações , Glioma do Nervo Óptico/epidemiologia , Glioma do Nervo Óptico/terapia , Fatores de Risco
14.
Int J Clin Oncol ; 25(10): 1763-1773, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32642850

RESUMO

PURPOSE: Posterior fossa brain tumours (PFT) and their treatment in young children are often associated with subsequent cognitive impairment. However, reported follow-up periods rarely exceed 10 years. This study reports very long-term cognitive consequences of surviving an early childhood PFT. METHODS: 62 adult survivors of a PFT, ascertained from a national register, diagnosed before 5 years of age, and a sibling control, received a single IQ assessment an average of 32 years (range 18-53) after initial diagnosis, using the Weschler Abbreviated Scale of Intelligence. Regression models were fitted to survivor-sibling pair differences on verbal and performance IQ (VIQ and PIQ) scores to investigate whether increasing time between PFT diagnosis and follow-up IQ assessment contributed to survivor-sibling IQ differences. RESULTS: At follow-up, survivors had, on average, VIQ 15 points and PIQ 19 points lower than their siblings. There was no significant effect of time since diagnosis on survivor-sibling VIQ difference. Survivors who received radiotherapy showed no significant effect of time since diagnosis on survivor-sibling PIQ difference. Survivors who did not receive radiotherapy demonstrated a trend for it to reduce. CONCLUSIONS: VIQ and PIQ deficits persist in adulthood, suggesting the effect of a fixed injury imposing on cognitive development, rather than an ongoing pathological process. IMPLICATIONS FOR CANCER SURVIVORS: The findings will help parents and others supporting survivors of an early life PFT to identify and plan for possible cognitive outcomes, and highlight the importance of early interventions to optimize cognitive function during the developmental period.


Assuntos
Neoplasias Encefálicas/psicologia , Sobreviventes de Câncer/psicologia , Cognição/fisiologia , Adolescente , Adulto , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Pré-Escolar , Feminino , Humanos , Testes de Inteligência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Irmãos , Adulto Jovem
15.
Neurooncol Pract ; 7(3): 277-287, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32537177

RESUMO

BACKGROUND: Survivors of childhood brain tumors or other acquired brain injury (ABI) are at risk of poor health-related quality of life (HRQoL); its valid and reliable assessment is essential to evaluate the effect of their illness on their lives. The aim of this review was to critically appraise psychometric properties of patient-reported outcome measures (PROMs) of HRQoL for these children, to be able to make informed decisions about the most suitable PROM for use in clinical practice. METHODS: We searched MEDLINE, EMBASE, and PsycINFO for studies evaluating measurement properties of HRQoL PROMs in children treated for brain tumors or other ABI. Methodological quality of relevant studies was evaluated using the consensus-based standards for the selection of health status measurement instruments checklist. RESULTS: Eight papers reported measurement properties of 4 questionnaires: Health Utilities Index (HUI), PedsQL Core and Brain Tumor Modules, and Child and Family Follow-up Survey (CFFS). Only the CFFS had evidence of content and structural validity. It also demonstrated good internal consistency, whereas both PedsQL modules had conflicting evidence regarding this. Conflicting evidence regarding test-retest reliability was reported for the HUI and PedsQL Core Module only. Evidence of measurement error/precision was favorable for HUI and CFFS and absent for both PedsQL modules. All 4 PROMs had some evidence of construct validity/hypothesis testing but no evidence of responsiveness to change. CONCLUSIONS: Valid and reliable assessment is essential to evaluate impact of ABI on young lives. However, measurement properties of PROMs evaluating HRQoL appropriate for this population require further evaluation, specifically construct validity, internal consistency, and responsiveness to change.

16.
Mol Pharm ; 17(6): 2083-2098, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32348676

RESUMO

Key challenges hindering the clinical translation of the use of nanoparticles (NP) for delivery of drugs to tumors are inadequate drug loading and premature drug release. This study focused on understanding the conditions required to produce nanoparticles that can reach their target site with sufficient drug loading and drug retention for effective pharmacological action. Etoposide, etoposide phosphate, and teniposide were screened against modified poly(glycerol) adipate (PGA) based polymers by monitoring drug release from 40% drug in polymer films and using Fourier transform infrared spectroscopy (FTIR) and contact angle measurements to help understand the release results. Polymers were matched with the specific drugs based on the interactions observed. NP were then prepared by an interfacial deposition method. NPs were characterized and resulted in drug loadings ranging from 3.5% and 5%, respectively, for etoposide phosphate and etoposide with PGA modified with stearate (PGA85%C18) up to 13.4% for teniposide with PGA modified with tryptophan (PGA50%Try) and drug release of just 22-35% over 24 h. Assessment of cytotoxicity showed that etoposide nanoparticles with PGA85%C18 were more potent than an equivalent amount of free drug. This screening method to match polymers to drugs to monitor based drug and polymer interactions thus resulted in the formulation of nanoparticles with higher drug loading and slower release and potential for further development for clinical applications.


Assuntos
Portadores de Fármacos/química , Polímeros/química , Liberação Controlada de Fármacos , Nanopartículas/química , Poliésteres/química
17.
Sci Rep ; 10(1): 3344, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-32094393

RESUMO

Optic Pathway Glioma (OPG) is a relatively common brain tumour in childhood; however, there is scarce understanding of neuropsychological sequelae in these survivors. In this study, 12 children with diagnosis of OPG before 6 years of age received a comprehensive standardised assessment of visual perception, general intelligence and academic achievement, using adjustments to visual materials of the tests, to examine the extent of concurrent impairment in these functional domains. Information about vision, clinical and socio-demographic factors were extracted from medical records to assess the associations of neuropsychological outcomes with clinical and socio-demographic factors. Children with OPG exhibited high within-patient variability and moderate group-level impairment compared to test norms. Visual perception was the most impaired domain, while scholastic progression was age-appropriate overall. For cognition, core verbal and visuo-spatial reasoning skills were intact, whereas deficits were found in working memory and processing speed. Visual function was associated with tasks that rely on visual input. Children with OPG are at moderate risk of neuropsychological impairment, especially for visual perception and cognitive proficiency. Future research should elucidate further the relative contribution of vision loss and neurofibromatosis type 1 co-diagnosis within a large sample.


Assuntos
Glioma/psicologia , Testes Neuropsicológicos , Vias Visuais/patologia , Adolescente , Criança , Cognição , Feminino , Glioma/fisiopatologia , Humanos , Masculino , Resultado do Tratamento , Acuidade Visual , Vias Visuais/fisiopatologia
18.
Lancet Child Adolesc Health ; 4(3): 242-250, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31958415

RESUMO

Leptomeningeal malignancy complicates childhood cancers, including leukaemias, brain tumours, and solid tumours. In leukaemia, such malignancy is thought to invade leptomeninges via the vascular route. In brain tumours, dissemination from the primary tumour, before or after surgery, via CSF pathways is assumed; however, evidence exists to support the vascular route of dissemination. Success in treating leptomeningeal malignancy represents a rate-limiting step to cure, which has been successfully overcome in leukaemia with intensified systemic therapy combined with intra-CSF therapy, which replaced cranial radiotherapy for many patients. This de-escalated CNS-directed therapy is still associated with some neurotoxicity. The balanced benefit justifies exploration of ways to further de-escalate CNS-directed therapy. For primary brain tumours, standard therapy is craniospinal radiotherapy, but attendant risk of acute and delayed brain injury and endocrine deficiencies compounds post-radiation impairment of spinal growth. Alternative ways of treating leptomeninges by intensifying drug therapy delivered to CSF are being investigated-preliminary evidence suggests improved outcomes. This Review seeks to describe methods of intra-CSF drug delivery and drugs in use, and consider how the technique could be modified and additional drugs might be selected for this route of administration.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Sistemas de Liberação de Medicamentos/tendências , Leucemia/tratamento farmacológico , Neoplasias Meníngeas/tratamento farmacológico , Encéfalo/efeitos da radiação , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/patologia , Ensaios Clínicos como Assunto , Radiação Cranioespinal/efeitos adversos , Radiação Cranioespinal/normas , Quimioterapia Combinada/métodos , Sistema Endócrino/efeitos da radiação , Humanos , Leucemia/complicações , Leucemia/patologia , Neoplasias Meníngeas/irrigação sanguínea , Neoplasias Meníngeas/líquido cefalorraquidiano , Neoplasias Meníngeas/patologia , Síndromes Neurotóxicas/epidemiologia , Coluna Vertebral/efeitos da radiação
19.
Science ; 366(6463): 360-364, 2019 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-31624211

RESUMO

We report a stereolithographic three-dimensional printing approach for polymeric components that uses a mobile liquid interface (a fluorinated oil) to reduce the adhesive forces between the interface and the printed object, thereby allowing for a continuous and rapid print process, regardless of polymeric precursor. The bed area is not size-restricted by thermal limitations because the flowing oil enables direct cooling across the entire print area. Continuous vertical print rates exceeding 430 millimeters per hour with a volumetric throughput of 100 liters per hour have been demonstrated, and proof-of-concept structures made from hard plastics, ceramic precursors, and elastomers have been printed.


Assuntos
Impressão Tridimensional , Elastômeros , Oxigênio , Poliuretanos , Impressão Tridimensional/instrumentação , Temperatura
20.
Nanoscale ; 11(6): 3029, 2019 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-30675617

RESUMO

Correction for 'Electrostatics at the nanoscale' by David A. Walker et al., Nanoscale, 2011, 3, 1316-1344.

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