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1.
Nature ; 629(8013): 927-936, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38588697

RESUMO

Broad-spectrum RAS inhibition has the potential to benefit roughly a quarter of human patients with cancer whose tumours are driven by RAS mutations1,2. RMC-7977 is a highly selective inhibitor of the active GTP-bound forms of KRAS, HRAS and NRAS, with affinity for both mutant and wild-type variants3. More than 90% of cases of human pancreatic ductal adenocarcinoma (PDAC) are driven by activating mutations in KRAS4. Here we assessed the therapeutic potential of RMC-7977 in a comprehensive range of PDAC models. We observed broad and pronounced anti-tumour activity across models following direct RAS inhibition at exposures that were well-tolerated in vivo. Pharmacological analyses revealed divergent responses to RMC-7977 in tumour versus normal tissues. Treated tumours exhibited waves of apoptosis along with sustained proliferative arrest, whereas normal tissues underwent only transient decreases in proliferation, with no evidence of apoptosis. In the autochthonous KPC mouse model, RMC-7977 treatment resulted in a profound extension of survival followed by on-treatment relapse. Analysis of relapsed tumours identified Myc copy number gain as a prevalent candidate resistance mechanism, which could be overcome by combinatorial TEAD inhibition in vitro. Together, these data establish a strong preclinical rationale for the use of broad-spectrum RAS-GTP inhibition in the setting of PDAC and identify a promising candidate combination therapeutic regimen to overcome monotherapy resistance.


Assuntos
Antineoplásicos , Carcinoma Ductal Pancreático , Guanosina Trifosfato , Neoplasias Pancreáticas , Proteínas Proto-Oncogênicas p21(ras) , Animais , Feminino , Humanos , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Variações do Número de Cópias de DNA , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Genes myc , Guanosina Trifosfato/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto , Mutação
2.
Nature ; 604(7906): 525-533, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35388223

RESUMO

Over the past few decades, neuroimaging has become a ubiquitous tool in basic research and clinical studies of the human brain. However, no reference standards currently exist to quantify individual differences in neuroimaging metrics over time, in contrast to growth charts for anthropometric traits such as height and weight1. Here we assemble an interactive open resource to benchmark brain morphology derived from any current or future sample of MRI data ( http://www.brainchart.io/ ). With the goal of basing these reference charts on the largest and most inclusive dataset available, acknowledging limitations due to known biases of MRI studies relative to the diversity of the global population, we aggregated 123,984 MRI scans, across more than 100 primary studies, from 101,457 human participants between 115 days post-conception to 100 years of age. MRI metrics were quantified by centile scores, relative to non-linear trajectories2 of brain structural changes, and rates of change, over the lifespan. Brain charts identified previously unreported neurodevelopmental milestones3, showed high stability of individuals across longitudinal assessments, and demonstrated robustness to technical and methodological differences between primary studies. Centile scores showed increased heritability compared with non-centiled MRI phenotypes, and provided a standardized measure of atypical brain structure that revealed patterns of neuroanatomical variation across neurological and psychiatric disorders. In summary, brain charts are an essential step towards robust quantification of individual variation benchmarked to normative trajectories in multiple, commonly used neuroimaging phenotypes.


Assuntos
Encéfalo , Longevidade , Estatura , Encéfalo/anatomia & histologia , Humanos , Imageamento por Ressonância Magnética/métodos , Neuroimagem
3.
Hum Brain Mapp ; 45(4): e26660, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38488444

RESUMO

The early life environment programmes cortical architecture and cognition across the life course. A measure of cortical organisation that integrates information from multimodal MRI and is unbound by arbitrary parcellations has proven elusive, which hampers efforts to uncover the perinatal origins of cortical health. Here, we use the Vogt-Bailey index to provide a fine-grained description of regional homogeneities and sharp variations in cortical microstructure based on feature gradients, and we investigate the impact of being born preterm on cortical development at term-equivalent age. Compared with term-born controls, preterm infants have a homogeneous microstructure in temporal and occipital lobes, and the medial parietal, cingulate, and frontal cortices, compared with term infants. These observations replicated across two independent datasets and were robust to differences that remain in the data after matching samples and alignment of processing and quality control strategies. We conclude that cortical microstructural architecture is altered in preterm infants in a spatially distributed rather than localised fashion.


Assuntos
Recém-Nascido Prematuro , Nascimento Prematuro , Lactente , Gravidez , Feminino , Recém-Nascido , Humanos , Nascimento Prematuro/diagnóstico por imagem , Encéfalo , Imageamento por Ressonância Magnética , Cognição
4.
J Pediatr ; 267: 113897, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38171471

RESUMO

OBJECTIVE: To assess the relationships between (1) environmental and demographic factors and executive function (EF) in preschool children with congenital heart disease (CHD) and controls and (2) clinical and surgical risk factors and EF in preschool children with CHD. STUDY DESIGN: At 4-6 years of age, parents of children with CHD (n = 51) and controls (n = 124) completed the Behavior Rating Inventory of Executive Function, Preschool Version questionnaire and the Cognitively Stimulating Parenting Scale (CSPS). Multivariable general linear modeling assessed the relationship between Behavior Rating Inventory of Executive Function, Preschool Version composite scores (Inhibitory Self-Control Index [ISCI], Flexibility Index [FI], and Emergent Metacognition Index [EMI]) and group (CHD/control), sex, age at assessment, gestational age, Index of Multiple Deprivation, and CSPS scores. The relationships between CHD type, surgical factors, and brain magnetic resonance imaging injury rating and ISCI, FI, and EMI scores were assessed. RESULTS: The presence of CHD, age at assessment, sex, and Index of Multiple Deprivation were not associated with EF scores. Lower gestational age was associated with greater ISCI and FI scores, and age at assessment was associated with lower FI scores. Group significantly moderated the relationship between CSPS and EF, such that CSPS significantly predicted EF in children with CHD (ISCI: P = .0004; FI: P = .0015; EMI: P = .0004) but not controls (ISCI: P = .2727; FI: P = .6185; EMI: P = .3332). There were no significant relationships between EF scores and surgical factors, CHD type, or brain magnetic resonance imaging injury rating. CONCLUSIONS: Supporting parents to provide a cognitively stimulating home environment may improve EF in children with CHD. The home and parenting environment should be considered when designing intervention studies aimed at improving EF in this patient group.


Assuntos
Função Executiva , Cardiopatias Congênitas , Humanos , Pré-Escolar , Ambiente Domiciliar , Poder Familiar , Pais , Cardiopatias Congênitas/complicações
5.
Cereb Cortex ; 33(9): 5585-5596, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-36408638

RESUMO

Formation of the functional connectome in early life underpins future learning and behavior. However, our understanding of how the functional organization of brain regions into interconnected hubs (centrality) matures in the early postnatal period is limited, especially in response to factors associated with adverse neurodevelopmental outcomes such as preterm birth. We characterized voxel-wise functional centrality (weighted degree) in 366 neonates from the Developing Human Connectome Project. We tested the hypothesis that functional centrality matures with age at scan in term-born babies and is disrupted by preterm birth. Finally, we asked whether neonatal functional centrality predicts general neurodevelopmental outcomes at 18 months. We report an age-related increase in functional centrality predominantly within visual regions and a decrease within the motor and auditory regions in term-born infants. Preterm-born infants scanned at term equivalent age had higher functional centrality predominantly within visual regions and lower measures in motor regions. Functional centrality was not related to outcome at 18 months old. Thus, preterm birth appears to affect functional centrality in regions undergoing substantial development during the perinatal period. Our work raises the question of whether these alterations are adaptive or disruptive and whether they predict neurodevelopmental characteristics that are more subtle or emerge later in life.


Assuntos
Conectoma , Nascimento Prematuro , Lactente , Gravidez , Feminino , Recém-Nascido , Humanos , Imageamento por Ressonância Magnética , Encéfalo , Recém-Nascido Prematuro
6.
Proc Natl Acad Sci U S A ; 118(20)2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33972435

RESUMO

During the second and third trimesters of human gestation, rapid neurodevelopment is underpinned by fundamental processes including neuronal migration, cellular organization, cortical layering, and myelination. In this time, white matter growth and maturation lay the foundation for an efficient network of structural connections. Detailed knowledge about this developmental trajectory in the healthy human fetal brain is limited, in part, due to the inherent challenges of acquiring high-quality MRI data from this population. Here, we use state-of-the-art high-resolution multishell motion-corrected diffusion-weighted MRI (dMRI), collected as part of the developing Human Connectome Project (dHCP), to characterize the in utero maturation of white matter microstructure in 113 fetuses aged 22 to 37 wk gestation. We define five major white matter bundles and characterize their microstructural features using both traditional diffusion tensor and multishell multitissue models. We found unique maturational trends in thalamocortical fibers compared with association tracts and identified different maturational trends within specific sections of the corpus callosum. While linear maturational increases in fractional anisotropy were seen in the splenium of the corpus callosum, complex nonlinear trends were seen in the majority of other white matter tracts, with an initial decrease in fractional anisotropy in early gestation followed by a later increase. The latter is of particular interest as it differs markedly from the trends previously described in ex utero preterm infants, suggesting that this normative fetal data can provide significant insights into the abnormalities in connectivity which underlie the neurodevelopmental impairments associated with preterm birth.


Assuntos
Córtex Cerebral/fisiologia , Corpo Caloso/fisiologia , Desenvolvimento Fetal/fisiologia , Tálamo/fisiologia , Substância Branca/fisiologia , Anisotropia , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/diagnóstico por imagem , Conectoma , Corpo Caloso/anatomia & histologia , Corpo Caloso/diagnóstico por imagem , Imagem de Tensor de Difusão , Feminino , Feto , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Neurogênese/fisiologia , Neurônios/citologia , Neurônios/fisiologia , Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Tálamo/anatomia & histologia , Tálamo/diagnóstico por imagem , Útero/diagnóstico por imagem , Útero/fisiologia , Substância Branca/anatomia & histologia , Substância Branca/diagnóstico por imagem
7.
BMC Emerg Med ; 24(1): 75, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38679713

RESUMO

OBJECTIVE: Distribution of take-home naloxone (THN) by emergency services may increase access to THN and reduce deaths and morbidity from opioid overdose. As part of a feasibility study for a randomised controlled trial (RCT) of distribution of THN kits and education within ambulance services and Emergency Departments (EDs), we used qualitative methods to explore key stakeholders' perceptions of feasibility and acceptability of delivering the trial. METHODS: We undertook semi-structured interviews and focus groups with 26 people who use opioids and with 20 paramedics and ED staff from two intervention sites between 2019 and 2021. Interviews and focus groups were recorded, transcribed verbatim and analysed using Framework Analysis. RESULTS: People using opioids reported high awareness of overdose management, including personal experience of THN use. Staff perceived emergency service provision of THN as a low-cost, low-risk intervention with potential to reduce mortality, morbidity and health service use. Staff understood the trial aims and considered it compatible with their work. All participants supported widening access to THN but reported limited trial recruitment opportunities partly due to difficulties in consenting patients during overdose. Procedural problems, restrictive recruitment protocols, limited staff buy-in and patients already owning THN limited trial recruitment. Determining trial effectiveness was challenging due to high levels of alternative community provision of THN. CONCLUSIONS: Distribution of THN in emergency settings was considered feasible and acceptable for stakeholders but an RCT to establish the effectiveness of THN delivery is unlikely to generate further useful evidence due to difficulties in recruiting patients and assessing benefits.


Assuntos
Grupos Focais , Naloxona , Antagonistas de Entorpecentes , Pesquisa Qualitativa , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Overdose de Drogas/prevenção & controle , Overdose de Drogas/tratamento farmacológico , Serviços Médicos de Emergência , Serviço Hospitalar de Emergência , Estudos de Viabilidade , Entrevistas como Assunto , Naloxona/administração & dosagem , Naloxona/uso terapêutico , Antagonistas de Entorpecentes/uso terapêutico , Antagonistas de Entorpecentes/administração & dosagem , Overdose de Opiáceos , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Reino Unido , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Microbiology (Reading) ; 169(1)2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36748549

RESUMO

While recent efforts to catalogue Earth's microbial diversity have focused upon surface and marine habitats, 12-20 % of Earth's biomass is suggested to exist in the terrestrial deep subsurface, compared to ~1.8 % in the deep subseafloor. Metagenomic studies of the terrestrial deep subsurface have yielded a trove of divergent and functionally important microbiomes from a range of localities. However, a wider perspective of microbial diversity and its relationship to environmental conditions within the terrestrial deep subsurface is still required. Our meta-analysis reveals that terrestrial deep subsurface microbiota are dominated by Betaproteobacteria, Gammaproteobacteria and Firmicutes, probably as a function of the diverse metabolic strategies of these taxa. Evidence was also found for a common small consortium of prevalent Betaproteobacteria and Gammaproteobacteria operational taxonomic units across the localities. This implies a core terrestrial deep subsurface community, irrespective of aquifer lithology, depth and other variables, that may play an important role in colonizing and sustaining microbial habitats in the deep terrestrial subsurface. An in silico contamination-aware approach to analysing this dataset underscores the importance of downstream methods for assuring that robust conclusions can be reached from deep subsurface-derived sequencing data. Understanding the global panorama of microbial diversity and ecological dynamics in the deep terrestrial subsurface provides a first step towards understanding the role of microbes in global subsurface element and nutrient cycling.


Assuntos
Gammaproteobacteria , Microbiota , Microbiologia da Água , Bactérias/genética , Microbiota/genética , Biomassa , Metagenômica , RNA Ribossômico 16S
9.
Magn Reson Med ; 89(3): 1016-1025, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36372971

RESUMO

PURPOSE: Ultralow-field (ULF) point-of-care MRI systems allow image acquisition without interrupting medical provision, with neonatal clinical care being an important potential application. The ability to measure neonatal brain tissue T1 is a key enabling technology for subsequent structural image contrast optimization, as well as being a potential biomarker for brain development. Here we describe an optimized strategy for neonatal T1 mapping at ULF. METHODS: Examinations were performed on a 64-mT portable MRI system. A phantom validation experiment was performed, and a total of 33 in vivo exams were acquired from 28 neonates with postmenstrual age ranging from 31+4 to 49+0  weeks. Multiple inversion-recovery turbo spin-echo sequences were acquired with differing inversion and repetition times. An analysis pipeline incorporating inter-sequence motion correction generated proton density and T1 maps. Regions of interest were placed in the cerebral deep gray matter, frontal white matter, and cerebellum. Weighted linear regression was used to predict T1 as a function of postmenstrual age. RESULTS: Reduction of T1 with postmenstrual age is observed in all measured brain tissue; the change in T1 per week and 95% confidence intervals is given by dT1  = -21 ms/week [-25, -16] (cerebellum), dT1  = -14 ms/week [-18, -10] (deep gray matter), and dT1  = -35 ms/week [-45, -25] (white matter). CONCLUSION: Neonatal T1 values at ULF are shorter than those previously described at standard clinical field strengths, but longer than those of adults at ULF. T1 reduces with postmenstrual age and is therefore a candidate biomarker for perinatal brain development.


Assuntos
Encéfalo , Substância Branca , Adulto , Recém-Nascido , Humanos , Lactente , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Cerebelo , Modelos Lineares , Mapeamento Encefálico/métodos
10.
PLoS Biol ; 18(11): e3000976, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33226978

RESUMO

Interruption to gestation through preterm birth can significantly impact cortical development and have long-lasting adverse effects on neurodevelopmental outcome. We compared cortical morphology captured by high-resolution, multimodal magnetic resonance imaging (MRI) in n = 292 healthy newborn infants (mean age at birth = 39.9 weeks) with regional patterns of gene expression in the fetal cortex across gestation (n = 156 samples from 16 brains, aged 12 to 37 postconceptional weeks [pcw]). We tested the hypothesis that noninvasive measures of cortical structure at birth mirror areal differences in cortical gene expression across gestation, and in a cohort of n = 64 preterm infants (mean age at birth = 32.0 weeks), we tested whether cortical alterations observed after preterm birth were associated with altered gene expression in specific developmental cell populations. Neonatal cortical structure was aligned to differential patterns of cell-specific gene expression in the fetal cortex. Principal component analysis (PCA) of 6 measures of cortical morphology and microstructure showed that cortical regions were ordered along a principal axis, with primary cortex clearly separated from heteromodal cortex. This axis was correlated with estimated tissue maturity, indexed by differential expression of genes expressed by progenitor cells and neurons, and engaged in stem cell differentiation, neuron migration, and forebrain development. Preterm birth was associated with altered regional MRI metrics and patterns of differential gene expression in glial cell populations. The spatial patterning of gene expression in the developing cortex was thus mirrored by regional variation in cortical morphology and microstructure at term, and this was disrupted by preterm birth. This work provides a framework to link molecular mechanisms to noninvasive measures of cortical development in early life and highlights novel pathways to injury in neonatal populations at increased risk of neurodevelopmental disorder.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/metabolismo , Feto/anatomia & histologia , Feto/metabolismo , Encéfalo/diagnóstico por imagem , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/metabolismo , Feminino , Maturidade dos Órgãos Fetais/genética , Feto/diagnóstico por imagem , Neuroimagem Funcional , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Imageamento por Ressonância Magnética Multiparamétrica , Neurogênese/genética , Gravidez , Nascimento Prematuro , Análise Espaço-Temporal
12.
Clin Radiol ; 78(4): e313-e318, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36754714

RESUMO

AIM: To investigate the real-world clinical performance of the decision-support software "e-CTA" (e-Stroke Suite, Brainomix Limited, Oxford UK) for the detection of acute intracranial large-vessel occlusion (LVO) on computed tomography (CT) angiography at a UK district general hospital. MATERIALS AND METHODS: The retrospective study included 300 consecutive CT angiograms of the head and neck performed between 8 March 2021 and 20 May 2021. e-CTA findings were recorded and compared with the radiologist report. Cases in which there was disagreement between e-CTA and the radiologist were reviewed by a sub-specialist vascular radiologist as the reference standard. RESULTS: The incidence of intracranial LVO was 7%. e-CTA correctly identified 18 of 21 intracranial proximal LVOs (86%). There were 34 false positives. The sensitivity was 0.86 (95% confidence interval [CI], 0.64-0.97), with specificity of 0.88 (95% CI, 0.83-0.91). The positive predictive value was 0.35 (95% CI, 0.27-0.43). The negative predictive value was 0.99 (95% CI, 0.96-1.00). CONCLUSION: Sensitivity, specificity, and negative predictive values were similar to those reported in the literature (Seker et al., Int J Stroke. 2021; 17:77-82); however, the positive predictive value for e-CTA was significantly lower. In practice, this meant that over half of all reported occlusions by the software were false positives. Radiologists should be aware of these metrics in order to assign appropriate weight to software findings when formulating a report. Differences in population demographics, scanners, CT protocols, and incidence are all factors potentially influencing software accuracy. Local validation testing may help provide accuracy metrics more relevant to individual institutions.


Assuntos
Angiografia por Tomografia Computadorizada , Acidente Vascular Cerebral , Humanos , Angiografia por Tomografia Computadorizada/métodos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Software , Angiografia , Angiografia Cerebral/métodos , Sensibilidade e Especificidade
13.
Health Educ Res ; 38(3): 241-253, 2023 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-36715722

RESUMO

Early intervention to support mental health and well-being of school-aged children may be of significant benefit in preventing escalation of mental health problems in later life. While there are limitations to current understanding of the best ways for schools to support mental well-being, a whole school approach (WSA), involving all those who are part of the school system in creating and sustaining a supportive environment where health is prioritized, may be effective. This research explored stakeholder views of this approach, as part of a contract commissioned by the Welsh Government to conduct an evaluability assessment of a WSA. Semistructured focus groups and interviews were completed with stakeholders from the health and education sectors, as well as parents, to explore how a WSA may operate in a Welsh context and barriers and facilitators to potential implementation and outcomes. Findings suggest that existing pressures on schools may impact implementation of a WSA, with school staff already time poor and many staff experiencing their own mental well-being challenges. Implementation may be supported by clear guidance at local and national levels, funding for staff time and training and stakeholder involvement at all stages. Long-term monitoring and evaluation are also needed to understand system changes.


Assuntos
Saúde Mental , Instituições Acadêmicas , Criança , Humanos , País de Gales , Grupos Focais , Emoções
14.
Public Health ; 218: 12-20, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36933354

RESUMO

INTRODUCTION: The UK shielding policy intended to protect people at the highest risk of harm from COVID-19 infection. We aimed to describe intervention effects in Wales at 1 year. METHODS: Retrospective comparison of linked demographic and clinical data for cohorts comprising people identified for shielding from 23 March to 21 May 2020; and the rest of the population. Health records were extracted with event dates between 23 March 2020 and 22 March 2021 for the comparator cohort and from the date of inclusion until 1 year later for the shielded cohort. RESULTS: The shielded cohort included 117,415 people, with 3,086,385 in the comparator cohort. The largest clinical categories in the shielded cohort were severe respiratory condition (35.5%), immunosuppressive therapy (25.9%) and cancer (18.6%). People in the shielded cohort were more likely to be female, aged ≥50 years, living in relatively deprived areas, care home residents and frail. The proportion of people tested for COVID-19 was higher in the shielded cohort (odds ratio [OR] 1.616; 95% confidence interval [CI] 1.597-1.637), with lower positivity rate incident rate ratios 0.716 (95% CI 0.697-0.736). The known infection rate was higher in the shielded cohort (5.9% vs 5.7%). People in the shielded cohort were more likely to die (OR 3.683; 95% CI: 3.583-3.786), have a critical care admission (OR 3.339; 95% CI: 3.111-3.583), hospital emergency admission (OR 2.883; 95% CI: 2.837-2.930), emergency department attendance (OR 1.893; 95% CI: 1.867-1.919) and common mental disorder (OR 1.762; 95% CI: 1.735-1.789). CONCLUSION: Deaths and healthcare utilisation were higher amongst shielded people than the general population, as would be expected in the sicker population. Differences in testing rates, deprivation and pre-existing health are potential confounders; however, lack of clear impact on infection rates raises questions about the success of shielding and indicates that further research is required to fully evaluate this national policy intervention.


Assuntos
COVID-19 , Humanos , Feminino , Masculino , COVID-19/epidemiologia , COVID-19/prevenção & controle , Estudos Retrospectivos , País de Gales/epidemiologia , Pandemias/prevenção & controle , Saúde Pública , Web Semântica , Política Pública
15.
Neuroimage ; 257: 119319, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35589001

RESUMO

The development of perinatal brain connectivity underpins motor, cognitive and behavioural abilities in later life. Diffusion MRI allows the characterisation of subtle inter-individual differences in structural brain connectivity. Individual brain connectivity maps (connectomes) are by nature high in dimensionality and complex to interpret. Machine learning methods are a powerful tool to uncover properties of the connectome which are not readily visible and can give us clues as to how and why individual developmental trajectories differ. In this manuscript we used Deep Neural Networks and Random Forests to predict demographic and neurodevelopmental characteristics from neonatal structural connectomes in a large sample of babies (n = 524) from the developing Human Connectome Project. We achieved an accurate prediction of post menstrual age (PMA) at scan in term-born infants (mean absolute error (MAE) = 0.72 weeks, r = 0.83 and p < 0.001). We also achieved good accuracy when predicting gestational age at birth in a cohort of term and preterm babies scanned at term equivalent age (MAE = 2.21 weeks, r = 0.82, p < 0.001). We subsequently used sensitivity analysis to obtain feature relevance from our prediction models, with the most important connections for prediction of PMA and GA found to predominantly involve frontal and temporal regions, thalami, and basal ganglia. From our models of PMA at scan for infants born at term, we computed a brain maturation index (predicted age minus actual age) of individual preterm neonates and found a significant correlation between this index and motor outcome at 18 months corrected age. Our results demonstrate the applicability of machine learning techniques in analyses of the neonatal connectome and suggest that a neural substrate of brain maturation with implications for future neurodevelopment is detectable at term equivalent age from the neonatal connectome.


Assuntos
Conectoma , Encéfalo/diagnóstico por imagem , Conectoma/métodos , Imagem de Difusão por Ressonância Magnética , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Imageamento por Ressonância Magnética , Gravidez
16.
Hum Brain Mapp ; 43(7): 2249-2261, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35088920

RESUMO

In the mature human brain, the neural processing related to different body parts is reflected in patterns of functional connectivity, which is strongest between functional homologs in opposite cortical hemispheres. To understand how this organization is first established, we investigated functional connectivity between limb regions in the sensorimotor cortex in 400 preterm and term infants aged across the equivalent period to the third trimester of gestation (32-45 weeks postmenstrual age). Masks were obtained from empirically derived functional responses in neonates from an independent data set. We demonstrate the early presence of a crude but spatially organized functional connectivity, that rapidly matures across the preterm period to achieve an adult-like configuration by the normal time of birth. Specifically, connectivity was strongest between homolog regions, followed by connectivity between adjacent regions (different limbs but same hemisphere) already in the preterm brain, and increased with age. These changes were specific to the sensorimotor network. Crucially, these trajectories were strongly dependent on age more than age of birth. This demonstrates that during the perinatal period the sensorimotor cortex undergoes preprogrammed changes determining the functional movement organization that are not altered by preterm birth in absence of brain injury.


Assuntos
Nascimento Prematuro , Córtex Sensório-Motor , Adulto , Encéfalo/fisiologia , Mapeamento Encefálico , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Vias Neurais/fisiologia , Córtex Sensório-Motor/diagnóstico por imagem
17.
Hum Brain Mapp ; 43(5): 1577-1589, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34897872

RESUMO

Infants born in early term (37-38 weeks gestation) experience slower neurodevelopment than those born at full term (40-41 weeks gestation). While this could be due to higher perinatal morbidity, gestational age at birth may also have a direct effect on the brain. Here we characterise brain volume and white matter correlates of gestational age at birth in healthy term-born neonates and their relationship to later neurodevelopmental outcome using T2 and diffusion weighted MRI acquired in the neonatal period from a cohort (n = 454) of healthy babies born at term age (>37 weeks gestation) and scanned between 1 and 41 days after birth. Images were analysed using tensor-based morphometry and tract-based spatial statistics. Neurodevelopment was assessed at age 18 months using the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III). Infants born earlier had higher relative ventricular volume and lower relative brain volume in the deep grey matter, cerebellum and brainstem. Earlier birth was also associated with lower fractional anisotropy, higher mean, axial, and radial diffusivity in major white matter tracts. Gestational age at birth was positively associated with all Bayley-III subscales at age 18 months. Regression models predicting outcome from gestational age at birth were significantly improved after adding neuroimaging features associated with gestational age at birth. This work adds to the body of evidence of the impact of early term birth and highlights the importance of considering the effect of gestational age at birth in future neuroimaging studies including term-born babies.


Assuntos
Imagem de Tensor de Difusão , Substância Branca , Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Gravidez , Substância Branca/diagnóstico por imagem
18.
J Neuroinflammation ; 19(1): 265, 2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36309753

RESUMO

Encephalopathy of prematurity (EoP) affects approximately 30% of infants born < 32 weeks gestation and is highly associated with inflammation in the foetus. Here we evaluated the efficacy of montelukast, a cysteinyl leukotriene receptor antagonist widely used to treat asthma in children, to ameliorate peripheral and central inflammation, and subsequent grey matter neuropathology and behaviour deficits in a mouse model of EoP. Male CD-1 mice were treated with intraperitoneal (i.p.) saline or interleukin-1beta (IL-1ß, 40 µg/kg, 5 µL/g body weight) from postnatal day (P)1-5 ± concomitant montelukast (1-30 mg/kg). Saline or montelukast treatment was continued for a further 5 days post-injury. Assessment of systemic and central inflammation and short-term neuropathology was performed from 4 h following treatment through to P10. Behavioural testing, MRI and neuropathological assessments were made on a second cohort of animals from P36 to 54. Montelukast was found to attenuate both peripheral and central inflammation, reducing the expression of pro-inflammatory molecules (IL-1ß, IL-6, TNF) in the brain. Inflammation induced a reduction in parvalbumin-positive interneuron density in the cortex, which was normalised with high-dose montelukast. The lowest effective dose, 3 mg/kg, was able to improve anxiety and spatial learning deficits in this model of inflammatory injury, and alterations in cortical mean diffusivity were not present in animals that received this dose of montelukast. Repurposed montelukast administered early after preterm birth may, therefore, improve grey matter development and outcome in EoP.


Assuntos
Encefalopatias , Nascimento Prematuro , Quinolinas , Recém-Nascido , Humanos , Feminino , Masculino , Animais , Camundongos , Substância Cinzenta , Nascimento Prematuro/tratamento farmacológico , Acetatos/uso terapêutico , Acetatos/farmacologia , Quinolinas/uso terapêutico , Quinolinas/farmacologia , Modelos Animais de Doenças , Inflamação/tratamento farmacológico
19.
FASEB J ; 35(10): e21881, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34478587

RESUMO

Group IIA secreted phospholipase A2 (PLA2G2A) hydrolyzes glycerophospholipids at the sn-2 position resulting in the release of fatty acids and lysophospholipids. C57BL/6 mice do not express Pla2g2a due to a frameshift mutation (wild-type [WT] mice). We previously reported that transgenic expression of human PLA2G2A in C57BL/6 mice (IIA+ mice) protects against weight gain and insulin resistance, in part by increasing total energy expenditure. Additionally, we found that brown and white adipocytes from IIA+ mice have increased expression of mitochondrial uncoupling markers, such as uncoupling protein 1 (UCP1), peroxisome proliferator-activated receptor-gamma coactivator, and PR domain containing 16, suggesting that the energy expenditure phenotype might be due to an increased thermogenic capacity in adipose tissue. Here, we further characterize the impact of PLA2G2A on thermogenic mechanisms in adipose tissue. Metabolic analysis of WT and IIA+ mice revealed that even when housed within their thermoneutral zone, IIA+ mice have elevated energy expenditure compared to WT littermates. Increased energy expenditure in IIA+ mice is associated with increased citrate synthase activity in brown adipose tissue (BAT) and increased mitochondrial respiration in both brown and white adipocytes. We also observed that direct addition of recombinant PLA2G2A enzyme to in vitro cultured adipocytes results in the marked induction of UCP1 protein expression. Finally, we report that PLA2G2A induces the expression of numerous transcripts related to energy substrate transport and metabolism in BAT, suggestive of an increase in substrate flux to fuel BAT activity. These data demonstrate that PLA2G2A enhances adipose tissue thermogenesis, in part, through elevated substrate delivery and increased mitochondrial content in BAT.


Assuntos
Tecido Adiposo Marrom/fisiopatologia , Metabolismo Energético , Fosfolipases A2 do Grupo II/fisiologia , Mitocôndrias/patologia , Termogênese , Proteína Desacopladora 1/metabolismo , Tecido Adiposo Branco/fisiopatologia , Animais , Transporte Biológico , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/metabolismo
20.
Org Biomol Chem ; 20(37): 7458-7466, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36094013

RESUMO

Herein, we introduce the first diphenylalanine dipeptide hydrogelator capped with the cinnamoyl functional group (Cin-L-F-L-F). We evaluate the effects of the cinnamoyl moiety on molecular self-assembly events and resultant physical properties of the hydrogel formed. In addition, we report our preliminary results of this dipeptide's cytotoxicity against glioblastoma (GBM) cancer cells.


Assuntos
Dipeptídeos , Hidrogéis , Dipeptídeos/química , Dipeptídeos/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Fenilalanina/química , Fenilalanina/farmacologia
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