Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 4.812
Filtrar
Mais filtros








Intervalo de ano de publicação
1.
Nature ; 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39385030

RESUMO

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype and has the highest rate of recurrence1. The predominant standard of care for advanced TNBC is systemic chemotherapy with or without immunotherapy; however, responses are typically short lived1,2. Thus, there is an urgent need to develop more effective treatments. Components of the PI3K pathway represent plausible therapeutic targets; more than 70% of TNBCs have alterations in PIK3CA, AKT1 or PTEN3-6. However, in contrast to hormone-receptor-positive tumours, it is still unclear whether or how triple-negative disease will respond to PI3K pathway inhibitors7. Here we describe a promising AKT-inhibitor-based therapeutic combination for TNBC. Specifically, we show that AKT inhibitors synergize with agents that suppress the histone methyltransferase EZH2 and promote robust tumour regression in multiple TNBC models in vivo. AKT and EZH2 inhibitors exert these effects by first cooperatively driving basal-like TNBC cells into a more differentiated, luminal-like state, which cannot be effectively induced by either agent alone. Once TNBCs are differentiated, these agents kill them by hijacking signals that normally drive mammary gland involution. Using a machine learning approach, we developed a classifier that can be used to predict sensitivity. Together, these findings identify a promising therapeutic strategy for this highly aggressive tumour type and illustrate how deregulated epigenetic enzymes can insulate tumours from oncogenic vulnerabilities. These studies also reveal how developmental tissue-specific cell death pathways may be co-opted for therapeutic benefit.

2.
J Surg Educ ; 81(12): 103274, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39378674

RESUMO

OBJECTIVE: There is concern that current surgical residents are suboptimally prepared for autonomous practice. This qualitative study aimed to clarify perceptions of competency, autonomy and surgical training goals by Canadian cardiac surgery programs and trainees. DESIGN: This was a qualitative study using semistructured interviews. These were audio recorded and transcribed verbatim. We used thematic analysis and content analysis to deductively analyze interview transcripts. From this, we identified major themes describing competency, autonomy, and goals of surgical training. SETTING: All interviews were conducted online over Zoom. PARTICIPANTS: We interviewed 16 individuals (7 trainees and 9 program directors) from 10 Canadian cardiac surgery training programs. RESULTS: Both trainees and staff agreed that the goal of surgical residency is to produce competent, not autonomous, surgeons. When defining competency, both faculty and trainees identified the importance of technical skills and nontechnical skills, such as surgical decision-making. Both groups believed autonomy and competency to be different, wherein autonomy assumes competency and is distinguished by the ability to make decisions independently. Importantly, 81% (n=13) believed that nontechnical skills were more important for independent practice than technical skills. Only 57% (n=4) of trainees and 33% (n=3) of staff surgeons felt that the current RCPSC competencies were reasonable to achieve during residency training. CONCLUSION: We have identified several important discrepancies in the perceptions of competency, autonomy, and surgical training goals. The RCPSC (Royal College of Physicians and Surgeons of Canada) stated goal of producing trainees who are ready for independent practice is discordant with the perspective of Canadian cardiac surgery programs. Many staff and trainees do not feel that the currently espoused competencies are feasible to achieve by graduation. The results of our study will allow us to identify the barriers during training to produce trainees ready for independent practice.

3.
Phys Med Biol ; 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39378896

RESUMO

Objective.This study presents a universal phantom for positron emission tomography (PET) that allows arbitrary static and dynamic activity distributions of various complexities to be generated using a single PET acquisition. Approach.We collected a high-statistics dataset (with a total of 22.4×109prompt coincidences and an event density of 2.75×106events/mm3) by raster-scanning a single plane with a22Na point source mounted on a robotic arm in the field-of-view of the uEXPLORER PET/CT scanner. The source position was determined from the reconstructed dynamic frames. Uniquely, true coincidences were separated from scattered and random events based on the distance between their line-of-response and the known source location. Finally, we randomly sampled the dataset to generate the desired activity distributions modeling several different phantoms. Main results.Overall, the target and the reconstructed phantom images had good agreement. The analysis of a simple geometric distribution showed high quantitative accuracy of the phantom, with mean error of <-3.0% relative to the ground truth for activity concentrations ranging from 5.3 to 47.7 kBq/ml. The model of a high-resolution18F-fluorodeoxyglucose distribution in the brain illustrates the usefulness of the technique in simulating realistic static neuroimaging studies. A dynamic18F-florbetaben study was modeled based on a time-activity curve of a human study and a segmented brain phantom with no coincidences repeating between frames. For all time points, the mean voxel-wise errors ranged from -4.4% to -0.7% in grey matter and from -3.9% to +2.8% in white matter. Significance.The proposed phantom technique is highly flexible and allows modeling of static and dynamic brain PET studies with high quantitative accuracy. It overcomes several key limitations of the existing phantoms and has many promising applications for the purposes of image reconstruction, data correction methods, and system performance evaluation, particularly for new high-performance dedicated brain PET scanners. .

4.
Chem Soc Rev ; 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39356078

RESUMO

Supported metal catalysts are essential to a plethora of processes in the chemical industry. The overall performance of these catalysts depends strongly on the interaction of adsorbates at the atomic level, which can be manipulated and controlled by the different constituents of the active material (i.e., support and active metal). The description of catalyst activity and the relationship between active constituent and the support, or metal-support interactions (MSI), in heterogeneous (thermo)catalysts is a complex phenomenon with multivariate (dependent and independent) contributions that are difficult to disentangle, both experimentally and theoretically. So-called "strong metal-support interactions" have been reported for several decades and summarized in excellent review articles. However, in recent years, there has been a proliferation of new findings related to atomically dispersed metal sites, metal oxide defects, and, for example, the generation and evolution of MSI under reaction conditions, which has led to the designation of (sub)classifications of MSI deserving to be critically and systematically evaluated. These include dynamic restructuring under alternating redox and reaction conditions, adsorbate-induced MSI, and evidence of strong interactions in oxide-supported metal oxide catalysts. Here, we review recent literature on MSI in oxide-supported metal particles to provide an up-to-date understanding of the underlying physicochemical principles that dominate the observed effects in supported metal atomic, cluster, and nanoparticle catalysts. Critical evaluation of different subclassifications of MSI is provided, along with discussions on the formation mechanisms, theoretical and characterization advances, and tuning strategies to manipulate catalytic reaction performance. We also provide a perspective on the future of the field, and we discuss the analysis of different MSI effects on catalysis quantitatively.

5.
Health Qual Life Outcomes ; 22(1): 70, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39218951

RESUMO

BACKGROUND: Diabetes-specific quality of life (QoL) questionnaires are commonly used to assess the impact of diabetes and its management on an individual's quality of life. While several valid and reliable measures of diabetes-specific QoL exist, there is no consensus on which to use and in what setting. Furthermore, there is limited evidence of their acceptability to people with diabetes. Our aim was to explore perceptions of adults with type 1 diabetes (T1D) toward five diabetes-specific QoL measures. METHODS: Adults (aged 18 + years) with T1D living in Australia or the United Kingdom (UK) were eligible to take part in 'YourSAY: QoL', an online cross-sectional survey. Recruitment involved study promotion on diabetes-related websites and social media, as well as direct invitation of people with T1D via a hospital client list (UK only). In random order, participants completed five diabetes-specific QoL measures: Audit of Diabetes-Dependent Quality of Life (ADDQoL-19); Diabetes Care Profile: Social and Personal Factors subscale (DCP); DAWN Impact of Diabetes Profile (DIDP); Diabetes-Specific Quality of Life Scale: Burden Subscale (DSQoLS); Diabetes Quality of Life Questionnaire (Diabetes QOL-Q). They were invited to provide feedback on each questionnaire in the form of a brief free-text response. Responses were analysed using inductive, thematic template analysis. RESULTS: Of the N = 1,946 adults with T1D who completed the survey, 20% (UK: n = 216, Australia: n = 168) provided qualitative responses about ≥ 1 measure. All measures received both positive and negative feedback, across four themes: (1) clarity and ease of completion, e.g., difficulty isolating impact of diabetes, dislike of hypothetical questions, and preference for 'not applicable' response options; (2) relevance and comprehensiveness, e.g., inclusion of a wide range of aspects of life to improve personal relevance; (3) length and repetition, e.g., length to be balanced against respondent burden; (4) framing and tone, e.g., preference for respectful language and avoidance of extremes. CONCLUSIONS: These findings suggest opportunities to improve the relevance and acceptability of existing diabetes-specific QoL measures, and offer considerations for developing new measures, which need to be better informed by the preferences of people living with diabetes.


Assuntos
Diabetes Mellitus Tipo 1 , Pesquisa Qualitativa , Qualidade de Vida , Humanos , Diabetes Mellitus Tipo 1/psicologia , Diabetes Mellitus Tipo 1/terapia , Qualidade de Vida/psicologia , Masculino , Feminino , Adulto , Estudos Transversais , Inquéritos e Questionários , Pessoa de Meia-Idade , Austrália , Reino Unido , Adulto Jovem , Adolescente , Idoso , Percepção , Psicometria
7.
One Health ; 19: 100875, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39253387

RESUMO

Macaques (Macaca spp.) are reported in human-wildlife interaction in anthropogenic areas. The management of human-macaque interactions (HMI) requires an understanding of various perspectives and knowledge. One Health (OH) is a transdisciplinary approach to address the well-being and health of animals, humans, and ecosystems, which supports sustainable management through its three pillars: economy, ecology, and society. Thus, the OH approach could be applied to HMI management. To explore the HMI management within the context of the OH approach, we examined articles related to the management of HMI from 2013 to 2022 following the systematic review by PRISMA guidelines. Ninety-four publications were included in the study. Then, we extracted information on HMI framing, management activities, species, and location and categorized HMI framings and management activities into themes of three OH domains and three pillars of sustainability. We noticed an underrepresentation of the society and economy pillars in HMI management and the ecosystem health domain was the least explored in both the HMI and management activities. When we connected publications addressing all three pillars with OH domains in management activities, the number focused on ecosystem health (3/13) remained limited. The most frequently reported HMI theme was "crop feeding"(n=42) and management activities were "HMI management" (n=42). Most publications lacked any form of evaluation of the HMI management. The challenges to better consider ecosystem health in the HMI and to promote participatory governance present an opportunity to apply the OH approach in wildlife conservation and management.

8.
Br J Cancer ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251829

RESUMO

Breast cancer is the most common cancer in women, and incidence rates are rising, it is thought in part, due to increasing levels of obesity. Endocrine therapy (ET) remains the cornerstone of systemic therapy for early and advanced oestrogen receptor-positive (ER + ) breast cancer, but despite treatment advances, it is becoming more evident that obesity and insulin resistance are associated with worse outcomes. Here, we describe the current understanding of the relationship between both obesity and diabetes and the prevalence and outcomes for ER+ breast cancer. We also discuss the mechanisms associated with resistance to ET and the relationship to treatment toxicity.

9.
Cell Death Discov ; 10(1): 403, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39271670

RESUMO

Staphylococcus aureus is an important human commensal which persistently colonizes up to 30% of the human population, predominantly within the nasal cavity. The commensal lifestyle of S. aureus is complex, and the mechanisms underpinning colonization are not fully understood. S. aureus can induce an immunosuppressive environment in the nasal tissue (NT) by driving IL-10 and IL-27 to facilitate nasal colonization, indicating that S. aureus has the capacity to modulate the local immune environment for its commensal habitation. Mounting evidence suggests commensal bacteria drive type 1 interferons (IFN-I) to establish an immunosuppressive environment and whilst S. aureus can induce IFN-I during infection, its role in colonization has not yet been examined. Here, we show that S. aureus preferentially induces IFN signaling in macrophages. This IFN-I in turn upregulates expression of proapoptotic genes within macrophages culminating in caspase-3 cleavage. Importantly, S. aureus was found to drive phagocytic cell apoptosis in the nasal tissue during nasal colonization in an IFN-I dependent manner with colonization significantly reduced under caspase-3 inhibition. Overall, loss of IFN-I signaling significantly diminished S. aureus nasal colonization implicating a pivotal role for IFN-I in controlling S. aureus persistence during colonization through its ability to induce phagocyte apoptosis. Together, this study reveals a novel strategy utilized by S. aureus to circumvent host immunity in the nasal mucosa to facilitate nasal colonization.

10.
Biomicrofluidics ; 18(5): 054105, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39280192

RESUMO

The death of dopamine-producing neurons in the substantia nigra in the base of the brain is a defining pathological feature in the development of Parkinson's disease (PD). PD is, however, a multi-systemic disease, also affecting the peripheral nervous system and gastrointestinal tract (GIT) that interact via the gut-brain axis (GBA). Our dual-flow GIT-brain microphysiological system (MPS) was modified to investigate the gut-to-brain translocation of the neurotoxin trigger of PD, 1-methyl-4-phenylpyridinium (MPP+), and its impact on key GIT and brain cells that contribute to the GBA. The modular GIT-brain MPS in combination with quantitative and morphometric image analysis methods reproduces cell specific neurotoxin-induced dopaminergic cytotoxicity and mitochondria-toxicity with the drug having no detrimental impact on the viability or integrity of cellular membranes of GIT-derived colonic epithelial cells. Our findings demonstrate the utility and capability of the GIT-brain MPS for measuring neuronal responses and its suitability for identifying compounds or molecules produced in the GIT that can exacerbate or protect against neuronal inflammation and cell death.

11.
BMJ Open ; 14(9): e085365, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39284691

RESUMO

INTRODUCTION: Preterm birth (PTB) is strongly associated with encephalopathy of prematurity (EoP) and neurocognitive impairment. The biological axes linking PTB with atypical brain development are uncertain. We aim to elucidate the roles of neuroendocrine stress activation and immune dysregulation in linking PTB with EoP. METHODS AND ANALYSIS: PRENCOG (PREterm birth as a determinant of Neurodevelopment and COGnition in children: mechanisms and causal evidence) is an exposure-based cohort study at the University of Edinburgh. Three hundred mother-infant dyads comprising 200 preterm births (gestational age, GA <32 weeks, exposed) and 100 term births (GA >37 weeks, non-exposed), will be recruited between January 2023 and December 2027. We will collect parental and infant medical, demographic, socioeconomic characteristics and biological data which include placental tissue, umbilical cord blood, maternal and infant hair, infant saliva, infant dried blood spots, faecal material, and structural and diffusion MRI. Infant biosamples will be collected between birth and 44 weeks GA.EoP will be characterised by MRI using morphometric similarity networks (MSNs), hierarchical complexity (HC) and magnetisation transfer saturation imaging (MTsat). We will conduct: first, multivariable regressions and statistical association assessments to test how PTB-associated risk factors (PTB-RFs) relate to MSNs, HC and or MTsat; second, structural equation modelling to investigate neuroendocrine stress activation and immune dysregulation as mediators of PTB-RFs on features of EoP. PTB-RF selection will be informed by the variables that predict real-world educational outcomes, ascertained by linking the UK National Neonatal Research Database with the National Pupil Database. ETHICS AND DISSEMINATION: A favourable ethical opinion has been given by the South East Scotland Research Ethics Committee 02 (23/SS/0067) and NHS Lothian Research and Development (2023/0150). Results will be reported to the Medical Research Council, in scientific media, via stakeholder partners and on a website in accessible language (https://www.ed.ac.uk/centre-reproductive-health/prencog).


Assuntos
Cognição , Nascimento Prematuro , Humanos , Feminino , Recém-Nascido , Estudos de Coortes , Gravidez , Reino Unido , Fatores de Risco , Masculino , Lactente , Desenvolvimento Infantil , Recém-Nascido Prematuro , Idade Gestacional , Transtornos do Neurodesenvolvimento/etiologia , Imageamento por Ressonância Magnética , Projetos de Pesquisa
12.
Clin Epigenetics ; 16(1): 124, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256775

RESUMO

BACKGROUND: Plasma growth differentiation factor 15 (GDF15) and N-terminal proB-type natriuretic peptide (NT-proBNP) are cardiovascular biomarkers that associate with a range of diseases. Epigenetic scores (EpiScores) for GDF15 and NT-proBNP may provide new routes for risk stratification. RESULTS: In the Generation Scotland cohort (N ≥ 16,963), GDF15 levels were associated with incident dementia, ischaemic stroke and type 2 diabetes, whereas NT-proBNP levels were associated with incident ischaemic heart disease, ischaemic stroke and type 2 diabetes (all PFDR < 0.05). Bayesian epigenome-wide association studies (EWAS) identified 12 and 4 DNA methylation (DNAm) CpG sites associated (Posterior Inclusion Probability [PIP] > 95%) with levels of GDF15 and NT-proBNP, respectively. EpiScores for GDF15 and NT-proBNP were trained in a subset of the population. The GDF15 EpiScore replicated protein associations with incident dementia, type 2 diabetes and ischaemic stroke in the Generation Scotland test set (hazard ratios (HR) range 1.36-1.41, PFDR < 0.05). The EpiScore for NT-proBNP replicated the protein association with type 2 diabetes, but failed to replicate an association with ischaemic stroke. EpiScores explained comparable variance in protein levels across both the Generation Scotland test set and the external LBC1936 test cohort (R2 range of 5.7-12.2%). In LBC1936, both EpiScores were associated with indicators of poorer brain health. Neither EpiScore was associated with incident dementia in the LBC1936 population. CONCLUSIONS: EpiScores for serum levels of GDF15 and Nt-proBNP associate with body and brain health traits. These EpiScores are provided as potential tools for disease risk stratification.


Assuntos
Biomarcadores , Metilação de DNA , Diabetes Mellitus Tipo 2 , Fator 15 de Diferenciação de Crescimento , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Humanos , Fator 15 de Diferenciação de Crescimento/sangue , Fator 15 de Diferenciação de Crescimento/genética , Peptídeo Natriurético Encefálico/sangue , Peptídeo Natriurético Encefálico/genética , Fragmentos de Peptídeos/sangue , Fragmentos de Peptídeos/genética , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/genética , Metilação de DNA/genética , Biomarcadores/sangue , Escócia , Demência/sangue , Demência/genética , Epigênese Genética , AVC Isquêmico/sangue , AVC Isquêmico/genética , Teorema de Bayes , Estudos de Coortes
13.
Inorg Chem ; 63(40): 18981-18991, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39328180

RESUMO

Nickel phosphides are of particular interest because they are highly active and stable catalysts for petroleum/biorefinery and hydrogen production. Despite their significant catalytic potential, synthesizing various phase-pure nickel phosphide nanoparticles of uniform size remains a challenge. In this work, we develop a robust trioctylphosphine (TOP)-mediated route to make highly uniform phase-pure Ni12P5, Ni2P, and Ni5P4 nanoparticles. The synthetic route forms amorphous Ni70P30 nanoparticle intermediates. The reactions can be stopped at the amorphous stage when amorphous particles are desired. The amount of P incorporation can be controlled by varying the ratio of TOP to Ni(II). The mechanism for composition control involves the competition of the kinetics of two processes: the addition of the reduced Ni and the incorporation of P into Ni. Uniform Ni70P30 amorphous nanoparticles can be generated at a high TOP-to-Ni(II) ratio, where the P incorporation kinetics is made to dominate. Ni70P30 can later be transformed into phase-pure Ni12P5, Ni2P, and Ni5P4 nanocrystals of uniform size. The transformation can be controlled precisely by modulating the temperature. A UV-vis study coupled with theoretical modeling reveals Ni(0)-TOPx complexes along the synthetic path. This approach may be expanded to create other metal compounds, potentially enabling the synthesis of uniform nanoparticles of a greater variety.

14.
medRxiv ; 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39252929

RESUMO

Quantitative total-body PET imaging of blood flow can be performed with freely diffusible flow radiotracers such as 15O-water and 11C-butanol, but their short half-lives necessitate close access to a cyclotron. Past efforts to measure blood flow with the widely available radiotracer 18F-fluorodeoxyglucose (FDG) were limited to tissues with high 18F-FDG extraction fraction. In this study, we developed an early-dynamic 18F-FDG PET method with high temporal resolution kinetic modeling to assess total-body blood flow based on deriving the vascular transit time of 18F-FDG and conducted a pilot comparison study against a 11C-butanol reference. Methods: The first two minutes of dynamic PET scans were reconstructed at high temporal resolution (60×1 s, 30×2 s) to resolve the rapid passage of the radiotracer through blood vessels. In contrast to existing methods that use blood-to-tissue transport rate ( K 1 ) as a surrogate of blood flow, our method directly estimates blood flow using a distributed kinetic model (adiabatic approximation to the tissue homogeneity model; AATH). To validate our 18F-FDG measurements of blood flow against a flow radiotracer, we analyzed total-body dynamic PET images of six human participants scanned with both 18F-FDG and 11C-butanol. An additional thirty-four total-body dynamic 18F-FDG PET scans of healthy participants were analyzed for comparison against literature blood flow ranges. Regional blood flow was estimated across the body and total-body parametric imaging of blood flow was conducted for visual assessment. AATH and standard compartment model fitting was compared by the Akaike Information Criterion at different temporal resolutions. Results: 18F-FDG blood flow was in quantitative agreement with flow measured from 11C-butanol across same-subject regional measurements (Pearson R=0.955, p<0.001; linear regression y=0.973x-0.012), which was visually corroborated by total-body blood flow parametric imaging. Our method resolved a wide range of blood flow values across the body in broad agreement with literature ranges (e.g., healthy cohort average: 0.51±0.12 ml/min/cm3 in the cerebral cortex and 2.03±0.64 ml/min/cm3 in the lungs, respectively). High temporal resolution (1 to 2 s) was critical to enabling AATH modeling over standard compartment modeling. Conclusions: Total-body blood flow imaging was feasible using early-dynamic 18F-FDG PET with high-temporal resolution kinetic modeling. Combined with standard 18F-FDG PET methods, this method may enable efficient single-tracer flow-metabolism imaging, with numerous research and clinical applications in oncology, cardiovascular disease, pain medicine, and neuroscience.

15.
Int J Geriatr Psychiatry ; 39(9): e6151, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39297868

RESUMO

OBJECTIVES: To explore the strength of the association between cognitive functioning and depression and anxiety in older people without dementia. METHODS: An exploratory, cross-sectional analysis of Wave 1 (2004-2007) data from the Lothian Birth Cohort 1936 dataset. Three subgroups were based on Hospital Anxiety and Depression Scale (HADS) subscales: no probable anxiety or depression (N = 592), probable anxiety no depression (N = 122), probable depression with/without anxiety (depression) (N = 30). Regression analyses determined relationships between subgroups and identified cognitive test variables. RESULTS: Participants were 744 individuals (male = 385 [51.5%]; mean [M] age = 69.5 years [Standard deviation = 0.83]); characteristics for subgroups were similar. Participants with probable depression had slower simple reaction time scores than those with no anxiety or depression (regression slope [ß] on the log10 scale = 0.05, 95% Confidence Interval [0.03, 0.08], p ≤ 0.001). Those with probable anxiety had significantly worse scores on other tests: Spatial span (ß = -0.80 [-1.36, -0.25], p ≤ 0.005), Symbol Search (ß = -1.67 [-2.90, -0.45], p ≤ 0.01), Matrix Reasoning (ß = -1.58 [-2.55, -0.60], p ≤ 0.005) and Block Design (ß = -3.33 [-5.29, -1.37], p ≤ 0.001), than those without probable anxiety or depression. CONCLUSION: Probable depression and anxiety were found to be associated with lower cognitive function in those without evidence of dementia. People with probable anxiety showed poorer performance in tests that concerned making decisions. People with probable depression showed slower processing speed.


Assuntos
Transtorno Depressivo , Humanos , Feminino , Masculino , Idoso , Estudos Transversais , Escócia/epidemiologia , Transtorno Depressivo/epidemiologia , Transtorno Depressivo/psicologia , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/psicologia , Transtornos de Ansiedade/epidemiologia , Transtornos de Ansiedade/psicologia , Cognição/fisiologia , Testes Neuropsicológicos , Depressão/epidemiologia , Depressão/psicologia , Idoso de 80 Anos ou mais , Ansiedade/epidemiologia , Ansiedade/psicologia , Escalas de Graduação Psiquiátrica , Análise de Regressão , Estudos de Coortes , Tempo de Reação
16.
Sci Rep ; 14(1): 19348, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39164431

RESUMO

3D printing technologies such as fused filament fabrication (FFF) offer great opportunities to enable the fabrication of complex geometries without access to a workshop or knowledge of machining. By adding filler materials to the raw filaments used for FFF, the material properties of the plastic can be adapted. With the addition of neutron absorbing particles, filaments can be created that enable 3D printing of neutron shielding with arbitrary geometry. Two materials for FFF are presented with different mixing ratios of hexagonal Boron nitride (h-BN) and Polylactic acid (PLA). BNPLA25 with 25 %wt h-BN and BNPLA35 with 35 %wt h-BN are compared to the commercially available Addbor N25 material. To qualify the applicability of BNPLA25 and BNPLA35 as shielding material for neutron instrumentation, such as neutron imaging, we investigated the overall neutron attenuation, the influence of non-optimized print settings, as well as characterized the incoherent neutron scattering and the microstructure using neutron imaging, and time-of-flight small-angle-neutron-scattering. Finally, the tensile strength of the material was determined in standardized tensile tests. The measured neutron attenuation shows excellent agreement with analytical calculations, thus validating both the material composition and the calculation method. Approximately 6 mm (8 mm) BNPLA35 are needed for 1 × 10 - 3 transmission of a cold (thermal) neutron beam. Lack of extrusion due to suboptimal print settings can be compensated by increased thickness, clearly visible defects can be mitigated by 11-18% increase in thickness. Incoherent scattering is shown to be strongly reduced compared to pure PLA. The tensile strength of the material is shown not to be impacted by the h-BN filler. The good agreement between the measured attenuation and calculation, combined with the adoption of safety factor enables the quick and easy development as well as the performance estimation of shielding components. BNPLA is uniquely suited for 3D printing neutron shielding because of the combination of non-abrasive h-BN particles in standard PLA, which results in a filament that can be printed with almost any off-the-shelf printer and virtually no prior experience in 3D printing. This mitigates the slightly lower attenuation observed as compared to filaments containing B 4 C , which is highly abrasive and requires extensive additive manufacturing experience.

17.
Eur Respir J ; 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39209479

RESUMO

The global impacts of pulmonary hypertension (PH) were formally recognised in 1973 at the 1st World Health Organization meeting dedicated to primary pulmonary hypertension, held in Geneva. Investigations into disease pathogenesis and classification led to the development of numerous therapies over the ensuing decades. While the impacts of the disease have been lessened due to treatments, the symptoms and adverse effects of PH and its therapies on patients' wellbeing and mental health remain significant. As such, there is a critical need to enhance understanding of the challenges patients face on a global scale with respect to care access, multidimensional patient support and advocacy. In addition, thoughtful analysis of the potential benefits and utilisation of mechanisms for the incorporation of patient-reported outcomes into diagnosis and treatment plans is needed. A summary of these areas is included here. We present a report of global surveys of patient and provider experiences and challenges regarding care access and discuss possible solutions. Also addressed is the current state of PH patient associations around the world. Potential ways to enhance patient associations and enable them to provide the utmost support are discussed. A summary of relevant patient-reported outcome measures to assess health-related quality of life in PH is presented, with suggestions regarding incorporation of these tools in patient care and research. Finally, information on how current global threats such as pandemics, climate change and armed conflict may impact PH patients is offered, along with insights as to how they may be mitigated with advanced contingency planning.

18.
J Med Genet ; 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39209702

RESUMO

BACKGROUND: Most schwannomas are isolated tumours occurring in otherwise healthy people. However, bilateral vestibular schwannomas (BVS) or multiple non-vestibular schwannomas indicate an underlying genetic predisposition. This is most commonly NF2-related schwannomatosis (SWN), but when BVS are absent, this can also indicate SMARCB1-related or LZTR1-related SWN. METHODS: We assessed the variant detection rates for the three major SWN genes (NF2, LZTR1 and SMARCB1) in 154 people, from 150 families, who had at least one non-vestibular schwannoma, but who did not meet clinical criteria for NF2-related SWN at the time of genetic testing. RESULTS: We found that 17 (11%) people from 13 families had a germline SMARCB1 variant and 19 (12%) unrelated individuals had a germline LZTR1 variant. 19 people had an NF2 variant, but 18 of these were mosaic and 17 were only detected when 2 tumours were available for testing. The overall detection rate was 25% using blood alone, but increased to 36% when tumour analysis was included. Another 12 people had a germline variant of uncertain significance (VUS). CONCLUSIONS: There were similar proportions of LZTR1, SMARCB1 or mosaic NF2. However, since an NF2 variant was detected in tumours from 103 people, it is likely that further cases of mosaicism would be detected if more people had additional tumours available for analysis. In addition, if further evidence becomes available to show that the VUSs are pathogenic, this would significantly increase the proportion of people with a genetic diagnosis. Our results indicate the importance of comprehensive genetic testing and improved variant classification.

19.
J Nucl Med ; 65(9): 1481-1488, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39089813

RESUMO

Immunotherapies, especially checkpoint inhibitors such as anti-programmed cell death protein 1 (anti-PD-1) antibodies, have transformed cancer treatment by enhancing the immune system's capability to target and kill cancer cells. However, predicting immunotherapy response remains challenging. 18F-arabinosyl guanine ([18F]F-AraG) is a molecular imaging tracer targeting activated T cells, which may facilitate therapy response assessment by noninvasive quantification of immune cell activity within the tumor microenvironment and elsewhere in the body. The aim of this study was to obtain preliminary data on total-body pharmacokinetics of [18F]F-AraG as a potential quantitative biomarker for immune response evaluation. Methods: The study consisted of 90-min total-body dynamic scans of 4 healthy subjects and 1 non-small cell lung cancer patient who was scanned before and after anti-PD-1 immunotherapy. Compartmental modeling with Akaike information criterion model selection was used to analyze tracer kinetics in various organs. Additionally, 7 subregions of the primary lung tumor and 4 mediastinal lymph nodes were analyzed. Practical identifiability analysis was performed to assess the reliability of kinetic parameter estimation. Correlations of the SUVmean, the tissue-to-blood SUV ratio (SUVR), and the Logan plot slope (K Logan) with the total volume of distribution (V T) were calculated to identify potential surrogates for kinetic modeling. Results: Strong correlations were observed between K Logan and SUVR with V T, suggesting that they can be used as promising surrogates for V T, especially in organs with a low blood-volume fraction. Moreover, practical identifiability analysis suggested that dynamic [18F]F-AraG PET scans could potentially be shortened to 60 min, while maintaining quantification accuracy for all organs of interest. The study suggests that although [18F]F-AraG SUV images can provide insights on immune cell distribution, kinetic modeling or graphical analysis methods may be required for accurate quantification of immune response after therapy. Although SUVmean showed variable changes in different subregions of the tumor after therapy, the SUVR, K Logan, and V T showed consistent increasing trends in all analyzed subregions of the tumor with high practical identifiability. Conclusion: Our findings highlight the promise of [18F]F-AraG dynamic imaging as a noninvasive biomarker for quantifying the immune response to immunotherapy in cancer patients. Promising total-body kinetic modeling results also suggest potentially wider applications of the tracer in investigating the role of T cells in the immunopathogenesis of diseases.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Imunoterapia , Neoplasias Pulmonares , Receptor de Morte Celular Programada 1 , Humanos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/tratamento farmacológico , Cinética , Masculino , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Imagem Corporal Total , Feminino , Modelos Biológicos , Pessoa de Meia-Idade , Adulto , Idoso , Inibidores de Checkpoint Imunológico/uso terapêutico
20.
Phys Med Biol ; 69(18)2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39168154

RESUMO

Objective.Penalty parameters in penalized likelihood positron emission tomography (PET) reconstruction are typically determined empirically. The cross-validation log-likelihood (CVLL) method has been introduced to optimize these parameters by maximizing a CVLL function, which assesses the likelihood of reconstructed images using one subset of a list-mode dataset based on another subset. This study aims to validate the efficacy of the CVLL method in whole-body imaging for cancer patients using a conventional clinical PET scanner.Approach.Fifteen lung cancer patients were injected with 243.7 ± 23.8 MBq of [18F]FDG and underwent a 22 min PET scan on a Biograph mCT PET/CT scanner, starting at 60 ± 5 min post-injection. The PET list-mode data were partitioned by subsampling without replacement, with 20 minutes of data for image reconstruction using an in-house ordered subset expectation maximization algorithm and the remaining 2 minutes of data for cross-validation. Two penalty parameters, penalty strengthßand Fair penalty function parameterδ, were subjected to optimization. Whole-body images were reconstructed, and CVLL values were computed across various penalty parameter combinations. The optimal image corresponding to the maximum CVLL value was selected by a grid search for each patient.Main results.Theδvalue required to maximize the CVLL value was notably small (⩽10-6in this study). The influences of voxel size and scan duration on image optimization were investigated. A correlation analysis revealed a significant inverse relationship between optimalßand scan count level, with a correlation coefficient of -0.68 (p-value = 3.5 × 10-5). The optimal images selected by the CVLL method were compared with those chosen by two radiologists based on their diagnostic preferences. Differences were observed in the selection of optimal images.Significance.This study demonstrates the feasibility of incorporating the CVLL method into routine imaging protocols, potentially allowing for a wide range of combinations of injected radioactivity amounts and scan durations in modern PET imaging.


Assuntos
Processamento de Imagem Assistida por Computador , Neoplasias Pulmonares , Tomografia por Emissão de Pósitrons , Imagem Corporal Total , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imagem Corporal Total/métodos , Funções Verossimilhança , Masculino , Feminino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA