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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.
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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 , PsicometriaRESUMO
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.
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Bacterial extracellular vesicles (BEVs) are nano-size vesicles containing a cargo of bioactive molecules that can play key roles in microbe-microbe and microbe-host interactions. In tracking their biodistribution in vivo, BEVs can cross several physical host barriers including the intestinal epithelium, vascular endothelium, and blood-brain-barrier (BBB) to ultimately accumulate in tissues such as the liver, lungs, spleen, and the brain. This tissue-specific dissemination has been exploited for the delivery of biomolecules such as vaccines for mucosal delivery. Although numerous strategies for labeling and tracking BEVs have been described, most have constraints that impact on interpreting in vivo bioimaging patterns. Here, we describe a general method for labeling BEVs using lipophilic fluorescent membrane stains which can be adopted by non-expert users. We also describe how the procedure can be used to overcome potential limitations. Furthermore, we outline methods of quantitative ex vivo tissue imaging that can be used to evaluate BEV organ trafficking.
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Vesículas Extracelulares , Corantes Fluorescentes , Vesículas Extracelulares/metabolismo , Animais , Distribuição Tecidual , Camundongos , Corantes Fluorescentes/química , Coloração e Rotulagem/métodos , Bactérias/metabolismoRESUMO
BACKGROUND AND OBJECTIVES: The aging population is growing faster than all other demographic strata. With older age comes a greater risk of health conditions such as obesity and high blood pressure (BP). These cardiometabolic risk factors (CMRs) exhibit prominent sex differences in midlife and aging, yet their influence on brain health in females vs males is largely unexplored. In this study, we investigated sex differences in relationships between BP, body mass index (BMI), and brain age over time and tested for interactions with APOE ε4 genotype (APOE4), a known genetic risk factor of Alzheimer disease. METHODS: The sample included participants from 2 United Kingdom-based longitudinal birth cohorts, the Lothian Birth Cohort (1936) and Insight 46 (1946). Participants with MRI data from at least 1 time point were included to evaluate sex differences in associations between CMRs and brain age. The open-access software package brainageR 2.1 was used to estimate brain age for each participant. Linear mixed-effects models were used to assess the relationships between brain age, BMI, BP, and APOE4 status (i.e., carrier vs noncarrier) in males and females over time. RESULTS: The combined sample comprised 1,120 participants (48% female) with a mean age (SD) of 73 (0.72) years in the Lothian Birth Cohort and 71 (0.68) years in Insight 46 at the time point 1 assessment. Approximately 30% of participants were APOE4 carriers. Higher systolic and diastolic BP was significantly associated with older brain age in females only (ß = 0.43-0.56, p < 0.05). Among males, higher BMI was associated with older brain age across time points and APOE4 groups (ß = 0.72-0.77, p < 0.05). In females, higher BMI was linked to older brain age among APOE4 noncarriers (ß = 0.68-0.99, p < 0.05), whereas higher BMI was linked to younger brain age among carriers, particularly at the last time point (ß = -1.75, p < 0.05). DISCUSSION: This study indicates sex-dependent and time-dependent relationships between CMRs, APOE4 status, and brain age. Our findings highlight the necessity of sex-stratified analyses to elucidate the role of CMRs in individual aging trajectories, providing a basis for developing personalized preventive interventions.
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Envelhecimento , Apolipoproteína E4 , Índice de Massa Corporal , Encéfalo , Caracteres Sexuais , Humanos , Masculino , Feminino , Apolipoproteína E4/genética , Idoso , Estudos Longitudinais , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/crescimento & desenvolvimento , Envelhecimento/genética , Pressão Sanguínea/fisiologia , Imageamento por Ressonância Magnética , Estudos de Coortes , Reino Unido/epidemiologia , Fatores de Risco CardiometabólicoRESUMO
Aurora A kinase, a cell division regulator, is frequently overexpressed in various cancers, provoking genome instability and resistance to antimitotic chemotherapy. Localization and enzymatic activity of Aurora A are regulated by its interaction with the spindle assembly factor TPX2. We have used fragment-based, structure-guided lead discovery to develop small molecule inhibitors of the Aurora A-TPX2 protein-protein interaction (PPI). Our lead compound, CAM2602, inhibits Aurora A:TPX2 interaction, binding Aurora A with 19 nM affinity. CAM2602 exhibits oral bioavailability, causes pharmacodynamic biomarker modulation, and arrests the growth of tumor xenografts. CAM2602 acts by a novel mechanism compared to ATP-competitive inhibitors and is highly specific to Aurora A over Aurora B. Consistent with our finding that Aurora A overexpression drives taxane resistance, these inhibitors synergize with paclitaxel to suppress the outgrowth of pancreatic cancer cells. Our results provide a blueprint for targeting the Aurora A-TPX2 PPI for cancer therapy and suggest a promising clinical utility for this mode of action.
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Here, we employed the nudged elastic band (NEB) method to simulate the diffusion of ferrocene through vanadyl phosphate (VOPO4), with a focus on understanding the diffusion pathways arising from the complex structure of ferrocene. We systematically evaluated a total of 36 potential diffusion paths, categorizing them into three groups based on their directional orientation: 15 paths between V sites along the [110] direction, 15 paths from V to P sites along the [100] direction, and 6 paths between P sites also along the [110] direction. Our analysis revealed that the energy barriers for diffusion along the [110] direction typically ranged between 0.25 and 0.35 eV, which are notably higher than those observed for pathways along the [100] direction, where the energy barriers ranged from 0.11 to 0.20 eV. To further elucidate the complex deformation of ferrocene during diffusion, we established four key measures to characterize the structural conformation: the angle of the axis of the ferrocene molecule relative to the [010] direction within the (001) plane, the dihedral angle between the two cyclopentadienyl rings, the orientation angle of the -CH bonds with respect to the [001] direction, and the angle between two -CH bonds from the two cyclopentadienyl rings.
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Adolescent development of human brain structural and functional networks is increasingly recognized as fundamental to emergence of typical and atypical adult cognitive and emotional proodal magnetic resonance imaging (MRI) data collected from N [Formula: see text] 300 healthy adolescents (51%; female; 14 to 26 y) each scanned repeatedly in an accelerated longitudinal design, to provide an analyzable dataset of 469 structural scans and 448 functional MRI scans. We estimated the morphometric similarity between each possible pair of 358 cortical areas on a feature vector comprising six macro- and microstructural MRI metrics, resulting in a morphometric similarity network (MSN) for each scan. Over the course of adolescence, we found that morphometric similarity increased in paralimbic cortical areas, e.g., insula and cingulate cortex, but generally decreased in neocortical areas, and these results were replicated in an independent developmental MRI cohort (N [Formula: see text] 304). Increasing hubness of paralimbic nodes in MSNs was associated with increased strength of coupling between their morphometric similarity and functional connectivity. Decreasing hubness of neocortical nodes in MSNs was associated with reduced strength of structure-function coupling and increasingly diverse functional connections in the corresponding fMRI networks. Neocortical areas became more structurally differentiated and more functionally integrative in a metabolically expensive process linked to cortical thinning and myelination, whereas paralimbic areas specialized for affective and interoceptive functions became less differentiated, as hypothetically predicted by a developmental transition from periallocortical to proisocortical organization of the cortex. Cytoarchitectonically distinct zones of the human cortex undergo distinct neurodevelopmental programs during typical adolescence.
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Imageamento por Ressonância Magnética , Neocórtex , Humanos , Adolescente , Feminino , Masculino , Neocórtex/diagnóstico por imagem , Neocórtex/crescimento & desenvolvimento , Neocórtex/fisiologia , Adulto , Adulto Jovem , Mapeamento Encefálico/métodos , Desenvolvimento do Adolescente/fisiologia , Rede Nervosa/fisiologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/crescimento & desenvolvimento , Encéfalo/diagnóstico por imagem , Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiologiaRESUMO
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.
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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 ComputadorizadaRESUMO
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.
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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.
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Standard Patlak plot is widely used to describe FDG kinetics for dynamic PET imaging. Whole-body Patlak parametric imaging remains constrained due to the need for a full-time input function. Here, we demonstrate the Relative Patlak (RP) plot, which eliminates the need for the early-time input function, for total-body parametric imaging and its application to clinical 20-min scan acquired in list-mode. We demonstrated that the RP intercept b' is equivalent to a ratio of standardized uptake value relative to the blood, while the RP slope Ki' is equal to the standard Patlak Ki multiplied by a global scaling factor for each subject. One challenge in applying RP to a short scan duration (20 min) is the high noise in parametric images. We applied a deep kernel method for noise reduction. Using the standard Patlak plot as the reference, the RP method was evaluated for lesion quantification, lesion-to-background contrast, and myocardial visualization in total-body parametric imaging with uEXPLORER in 22 human subjects who underwent a 1-h dynamic 18F-FDG scan. The RP method was also applied to the dynamic data regenerated from a clinical standard 20-min scan either at 1-h or 2-h post-injection for two cancer patients. We demonstrated that it is feasible to obtain high-quality parametric images from 20-min dynamic scans using the RP plot with a self-supervised deep-kernel noise reduction strategy. The RP Ki' highly correlated with Ki in lesions and major organs, demonstrating its quantitative potential across subjects. Compared to conventional SUVs, the Ki' images significantly improved lesion contrast and enabled visualization of the myocardium for potential cardiac assessment. The application of RP parametric imaging to two clinical scans also showed similar benefits. Total-body PET with the RP plot is feasible to generate parametric images from the dynamic data of a 20-min clinical scan.
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OBJECTIVE: To provide detailed guidance on the administration of systemic bevacizumab in patients with recurrent respiratory papillomatosis (RRP) based on a detailed review of the scientific literature and a consensus of experts with real-world clinical experience. METHODS: A bevacizumab consensus working group (N = 10) was composed of adult and pediatric otolaryngologists, adult and pediatric oncologists, and a representative from the RRP Foundation (RRPF), all with experience administering systemic bevacizumab in patients with RRP. After extensive review of the medical literature, a modified Delphi method-based survey series was utilized to establish consensus on the following key areas: clinical and patient characteristics ideal for treatment candidacy, patient perspective in treatment decisions, treatment access, initial dosing, monitoring, guidelines for tapering and discontinuation, and reintensifying therapy. RESULTS: Seventy-nine statements were identified across nine critical domains, and 45 reached consensus [clinical benefits of bevacizumab (3), patient and disease characteristics for treatment consideration (7), contraindications for treatment (3), shared decision-making (incorporating the patient perspective) (5), treatment access (3), initial dosing and administration (8), monitoring (7), tapering and discontinuation (6), and reintensification (3)]. CONCLUSION: This consensus statement provides the necessary guidance for clinicians to initiate systemic administration of bevacizumab and represents a potential paradigm shift toward nonsurgical treatment options for patients with RRP. LEVEL OF EVIDENCE: 5 Laryngoscope, 2024.
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An alternative method for characterizing optical propagation in waveguide structures based on scattered light imaging is presented and demonstrated for the spectral range of 450-980 nm. Propagation losses as low as 1.40 dB/cm are demonstrated in alumina spiral waveguides. AlGaAs-on-insulator waveguides are measured using a tunable laser and compared to cut-back measurements. On AlGaAs, a one-sigma uncertainty of 1.40 and 2.23 dB/cm for TE and TM polarizations is obtained for repetitions of measurements conducted on the same waveguide, highlighting the approach's reproducibility. An open-source toolbox is introduced, allowing for reliable processing of data and estimation of optical propagation losses.
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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.
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Blood-brain barrier (BBB) disruption is involved in the pathogenesis and progression of many neurological and systemic diseases. Non-invasive assessment of BBB permeability in humans has mainly been performed with dynamic contrast-enhanced magnetic resonance imaging, evaluating the BBB as a structural barrier. Here, we developed a novel non-invasive positron emission tomography (PET) method in humans to measure the BBB permeability of molecular radiotracers that cross the BBB through different transport mechanisms. Our method uses high-temporal resolution dynamic imaging and kinetic modeling to jointly estimate cerebral blood flow and tracer-specific BBB transport rate from a single dynamic PET scan and measure the molecular permeability-surface area (PS) product of the radiotracer. We show our method can resolve BBB PS across three PET radiotracers with greatly differing permeabilities, measure reductions in BBB PS of 18F-fluorodeoxyglucose (FDG) in healthy aging, and demonstrate a possible brain-body association between decreased FDG BBB PS in patients with metabolic dysfunction-associated steatotic liver inflammation. Our method opens new directions to efficiently study the molecular permeability of the human BBB in vivo using the large catalogue of available molecular PET tracers.
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BACKGROUND: Pulmonary fibrosis results from alveolar injury, leading to extracellular matrix remodelling and impaired lung function. This study aimed to classify patients with pulmonary fibrosis according to blood biomarkers to differentiate distinct disease patterns, known as endotypes. METHODS: In this cluster analysis, we first classified patients from the PROFILE study, a multicentre, prospective, observational cohort of individuals with incident idiopathic pulmonary fibrosis or non-specific interstitial pneumonia in the UK (Nottingham University Hospitals, Nottingham; and Royal Brompton Hospital, London). 13 blood biomarkers representing extracellular matrix remodelling, epithelial stress, and thrombosis were measured by ELISA in the PROFILE study. We classified patients by unsupervised consensus clustering. To evaluate generalisability, a machine learning classifier trained on biomarker signatures derived from consensus clustering was applied to a replication dataset from the Australian Idiopathic Pulmonary Fibrosis Registry (AIPFR). Biomarker associations with mortality and change in percentage of predicted forced vital capacity (FVC%) were assessed, adjusting for age, gender, baseline FVC%, and antifibrotic treatment and steroid treatment before and after baseline. Mortality risk associated with the clusters in the PROFILE cohort was evaluated with Cox proportional hazards models, and mixed-effects models were used to analyse how clustering was associated with longitudinal FVC% in the PROFILE and AIPFR cohorts. FINDINGS: 455 of 580 participants from the PROFILE study (348 [76%] men and 107 [24%] women; mean age 72·4 years [SD 8·3]) were included in the analysis. Within this group, three clusters were identified based on blood biomarkers. A basement membrane collagen (BM) cluster (n=248 [55%]) showed high concentrations of PRO-C4, PRO-C28, C3M, and C6M, whereas an epithelial injury (EI) cluster (n=109 [24%]) showed high concentrations of MMP-7, SP-D, CYFRA211, CA19-9, and CA-125. The third cluster (crosslinked fibrin [XF] cluster; n=98 [22%]) had high concentrations of X-FIB. In the replication dataset (117 of 833 patients from AIPFR; 87 [74%] men and 30 [26%] women; mean age 72·9 years [SD 7·9]), we identified the same three clusters (BM cluster, n=93 [79%]; EI cluster, n=8 [7%]; XF cluster, n=16 [14%]). These clusters showed similarities with clusters in the PROFILE dataset regarding blood biomarkers and phenotypic signatures. In the PROFILE dataset, the EI and XF clusters were associated with increased mortality risk compared with the BM cluster (EI vs BM: adjusted hazard ratio [HR] 1·88 [95% CI 1·42-2·49], p<0·0001; XF vs BM: adjusted HR 1·53 [1·13-2·06], p=0·0058). The EI cluster showed the greatest annual FVC% decline, followed by the BM and XF clusters. A similar FVC% decline pattern was observed in these clusters in the AIPFR replication dataset. INTERPRETATION: Blood biomarker clustering in pulmonary fibrosis identified three distinct blood biomarker signatures associated with lung function and prognosis, suggesting unique pulmonary fibrosis biomarker patterns. These findings support the presence of pulmonary fibrosis endotypes with the potential to guide targeted therapy development. FUNDING: None.
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Biomarcadores , Fibrose Pulmonar Idiopática , Humanos , Biomarcadores/sangue , Masculino , Feminino , Estudos Prospectivos , Idoso , Análise por Conglomerados , Fibrose Pulmonar Idiopática/sangue , Fibrose Pulmonar Idiopática/mortalidade , Fibrose Pulmonar Idiopática/diagnóstico , Fibrose Pulmonar Idiopática/fisiopatologia , Pessoa de Meia-Idade , Capacidade Vital , Reino UnidoRESUMO
Examining underlying neurostructural correlates of specific cognitive abilities is practically and theoretically complicated by the existence of the positive manifold (all cognitive tests positively correlate): if a brain structure is associated with a cognitive task, how much of this is uniquely related to the cognitive domain, and how much is due to covariance with all other tests across domains (captured by general cognitive functioning, also known as general intelligence, or 'g')? We quantitatively address this question by examining associations between brain structural and diffusion MRI measures (global tissue volumes, white matter hyperintensities, global white matter diffusion fractional anisotropy and mean diffusivity, and FreeSurfer processed vertex-wise cortical volumes, smoothed at 20mm fwhm) with g and cognitive domains (processing speed, crystallised ability, memory, visuospatial ability). The cognitive domains were modelled using confirmatory factor analysis to derive both hierarchical and bifactor solutions using 13 cognitive tests in 697 participants from the Lothian Birth Cohort 1936 study (mean age 72.5 years; SD = .7). Associations between the extracted cognitive factor scores for each domain and g were computed for each brain measure covarying for age, sex and intracranial volume, and corrected for false discovery rate. There were a range of significant associations between cognitive domains and global MRI brain structural measures (r range .008 to .269, p < .05). Regions implicated by vertex-wise regional cortical volume included a widespread number of medial and lateral areas of the frontal, temporal and parietal lobes. However, at both global and regional level, much of the domain-MRI associations were shared (statistically accounted for by g). Removing g-related variance from cognitive domains attenuated association magnitudes with global brain MRI measures by 27.9-59.7% (M = 46.2%), with only processing speed retaining all significant associations. At the regional cortical level, g appeared to account for the majority (range 22.1-88.4%; M = 52.8% across cognitive domains) of regional domain-specific associations. Crystallised and memory domains had almost no unique cortical correlates, whereas processing speed and visuospatial ability retained limited cortical volumetric associations. The greatest spatial overlaps across cognitive domains (as denoted by g) were present in the medial and lateral temporal, lateral parietal and lateral frontal areas.
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Encéfalo , Cognição , Inteligência , Humanos , Feminino , Inteligência/fisiologia , Masculino , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/anatomia & histologia , Cognição/fisiologia , Testes Neuropsicológicos , Coorte de Nascimento , Substância Branca/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Estudos de CoortesRESUMO
Metal phosphide-containing materials have emerged as a potential candidate of nonprecious metal-based catalysts for alkaline oxygen evolution reaction (OER). While it is known that metal phosphide undergoes structural evolution, considerable debate persists regarding the effects of dynamics on the surface activation and morphological stability of the catalysts. In this study, we synthesize NiP x -FeO x core-shell nanocatalysts with an amorphous NiP x core designed for enhanced OER activity. Using ex situ X-ray absorption spectroscopy, we elucidate the local structural changes as a function of the cyclic voltammetry cycles. Our studies suggest that the presence of corner-sharing octahedra in the FeO x shell improves structural rigidity through interlayer cross-linking, thereby inhibiting the diffusion of OH-/H2O. Thus, the FeO x shell preserves the amorphous NiP x core from rapid oxidation to Ni3(PO4)2 and Ni(OH)2. On the other hand, the incorporation of Ni from the core into the FeO x shell facilitates absorption of hydroxide ions for OER. As a result, Ni/Fe(OH) x at the surface oxidizes to the active γ-(oxy)hydroxide phase under the applied potentials, promoting OER. This intriguing synergistic behavior holds significance as such a synthetic route involving the FeO x shell can be extended to other systems, enabling manipulation of surface adsorption and diffusion of hydroxide ions. These findings also demonstrate that nanomaterials with core-shell morphologies can be tuned to leverage the strength of each metallic component for improved electrochemical activities.
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Objective: To investigate the ventilatory and circulatory differences between eccentric (ECC) and concentric (CON) cycling exercise at submaximal, low-dose intensity from onset to end-exercise in healthy middle-aged participants. Design: Randomized controlled crossover trial. Setting: The participants underwent 1 ECC and 1 CON test according to stepwise incremental exercise protocols at identical, submaximal intensities. Breath-by-breath analyses of ventilatory gas exchange and echocardiography were used to assess cardiopulmonary function during exercise. Participants: 24 healthy middle-aged, untrained participants (14 women, 10 men, 50±14 years) were included. Interventions: 1 ECC and 1 CON test at submaximal intensities. Main Outcome Measure: The main outcome was oxygen uptake (V'O2). Results: The V'O2 increase was reduced by -422 mL/min (-52%, 95% confidence interval: -513 to -292, P<.001) during ECC, as well as the ventilatory drive. Echocardiographic parameters, heart rate (-14%), cardiac output (-21%), stroke volume (-15%), and pulmonary artery pressure by tricuspid regurgitation pressure gradient (TRPG) (-26%) were also significantly reduced during ECC compared with CON at identical intensities. Participants reported significantly less dyspnea and unchanged perceived leg fatigue in ECC. Conclusion: ECC was well tolerated, and significant reductions were observed in V'O2, ventilation, and right ventricular load compared with CON, even at low intensity levels. This study, conducted on healthy middle-aged participants, did not raise concerns that would hinder further investigation of the effects of ECC in patients with severely limited cardiopulmonary disease, and it calls for further research on this topic.
RESUMO
Participant motion in brain magnetic resonance imaging is associated with processing problems including potentially non-useable/incomplete data. This has implications for representativeness in research. Few large studies have investigated predictors of increased motion in the first instance. We exploratively tested for association between multiple psychological and physical health traits with concurrent motion during T1 structural, diffusion, average resting-state and task functional magnetic resonance imaging in N = 52 951 UK Biobank imaging subsample participants. These traits included history of cardiometabolic, inflammatory, neurological and psychiatric conditions, as well as concurrent cognitive test scores and anthropometric traits. We tested for stability in motion in participants with longitudinal imaging data (n = 5305, average 2.64 years later). All functional and T1 structural motion variables were significantly intercorrelated (Pearson r range 0.3-0.8, all P < 0.001). Diffusion motion variables showed weaker correlations around r = 0.1. Most physical and psychological phenotypes showed significant association with at least one measure of increased motion including specifically in participants with complete useable data (highest ß = 0.66 for diabetes versus resting-state functional magnetic resonance imaging motion). Poorer values in most health traits predicted lower odds of complete imaging data, with the largest association for history of traumatic brain injury (odds ratio = 0.720, 95% confidence interval = 0.562 to 0.923, P = 0.009). Worse psychological and physical health are consistent predictors of increased average functional and structural motion during brain imaging and associated with lower odds of complete data. Average motion levels were largely consistent across modalities and longitudinally in participants with repeat data. Together, these findings have implications for representativeness and bias in imaging studies of generally healthy population samples.