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1.
ACS Appl Nano Mater ; 7(9): 10120-10129, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38752019

RESUMO

Nanostructured niobium-titanium carbonitrides, (Nb,Ti)C1-xNx, with the cubic-rock salt structure are prepared without the use of reactive gases via thermal treatment (700-1200 °C) under nitrogen of mixtures of guanidine carbonate and ammonium niobate (V) oxalate hydrate, with addition of ammonium titanyl oxalate monohydrate as a titanium source. The bulk structure and chemical composition of the materials are characterized using powder X-ray diffraction (XRD) and powder neutron diffraction, elemental homogeneity is studied using energy dispersive spectroscopy (EDS) mapping using transmission electron microscopy (TEM), and surface chemical analysis is examined using X-ray photoelectron spectroscopy (XPS). Nanoscale crystallites of between 10 and 50 nm are observed by TEM, where EDS reveals the homogeneity of metal distribution for the mixed-metal materials. Titanium carbonitrides are found to be air sensitive, reacting with air under ambient conditions, while titanium-niobium carbonitrides are found to degrade in aqueous sulfuric acid. The niobium carbonitrides, however, show some stability toward acidic solutions. Materials are produced with composition NbC1-xNx with x between 0.35 and 0.45, and more carbon-rich materials (x ≈ 0.35) are found as the synthesis temperature is increased, as proven by Rietveld refinement of crystal structure against powder neutron diffraction data. Despite phase purity seen by diffraction and negligible bulk carbon content, XPS shows a complex surface chemistry for the NbC1-xNx materials, with evidence for Nb2O5-like oxide species in a carbon-rich environment. The NbC1-xNx prepared at 900 °C has a surface area around 50 m2 g-1, making it suitable as a catalyst support. Loading with iridium provides a material active for the oxygen evolution reaction in 0.1 M sulfuric acid, with minimal leaching of either Nb or Ir after 1000 cycles.

2.
Cerebrovasc Dis ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38749409

RESUMO

BACKGROUND AND PURPOSE: We aimed to determine predictors of early (END) and delayed neurological deterioration (DND) and their association with functional outcome in patients with acute ischemic stroke (AIS) who participated in the international Enhanced Control of Hypertension and Thrombolysis Stroke Study (ENCHANTED). METHODS: END and DND were defined as scores of a ≥2 point increase on the National Institutes of Health Stroke Scale (NIHSS) or ≥1 point decrease on Glasgow coma scale, or death, from baseline to 24 hours and 24 hours to 72 hours, respectively. Multivariable logistic regression models were used to determine independent predictors of END and DND and their association with 90-day outcomes (dichotomous scores on the modified Rankin scale [mRS] of 2-6 vs 0-1 and 3-6 vs 0-2, and death). RESULTS: Of 4496 patients, 871 (19.4%) and 302 (8.4%) patients experienced END and DND, respectively. Higher baseline NIHSS score, older age, large artery occlusion due to significant atheroma, cardioembolic stroke subtype, hemorrhagic infarction and parenchymatous hematoma within 24 hours, were all independent predictors for both END (all P ≤0.01) and DND (all P ≤0.024). Moreover, higher baseline systolic blood pressure (BP) (odds ratio [OR] 1.07, 95% confidence interval [CI] 1.02-1.12), higher diastolic BP variability within 24 hours (OR 1.07, 95% CI 1.04-1.09), patients from Asia (OR 1.25, 95% CI 1.03-1.52) were the only independent predictors for END. However, Asian ethnicity was negatively associated with DND (OR 0.64, 95% CI 0.47-0.86). Hemorrhagic infarction and parenchymatous hematoma within 24 hours were the key predictor of END across all stroke subtypes. END and DND were all associated with a poor functional outcome at 90 days (all P<0.001). CONCLUSIONS: We identified overlapping and unique demographic and clinical predictors of END and DND after thrombolysis for acute ischemic stroke. Both END and DND predict unfavorable outcomes at 90 days.

3.
Diabet Med ; : e15332, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38751219

RESUMO

Diabetes is unique among chronic diseases because clinical outcomes are intimately tied to how the person living with diabetes reacts to and implements treatment recommendations. It is further characterised by widespread social stigma, judgement and paternalism. This physical, social and psychological burden collectively influences self-management behaviours. It is widely recognised that the individual's perspective about the impact of trying to manage the disease and the burden that self-management confers must be addressed to achieve optimal health outcomes. Standardised, rigorous assessment of mental and behavioural health status, in interaction with physical health outcomes is crucial to aid understanding of person-reported outcomes (PROs). Whilst tempting to conceptualise PROs as an issue of perceived quality of life (QoL), in fact health-related QoL is multi-dimensional and covers indicators of physical or functional health status, psychological and social well-being. This complexity is illuminated by the large number of person reported outcome measures (PROMs) that have been developed across multiple psychosocial domains. Often measures are used inappropriately or because they have been used in the scientific literature rather than based on methodological or outcome assessment rigour. Given the broad nature of psychosocial functioning/mental health, it is important to broadly define PROs that are evaluated in the context of therapeutic interventions, real-life and observational studies. This report summarises the central themes and lessons derived in the assessment and use of PROMs amongst adults with diabetes. Effective assessment of PROMs routinely in clinical research is crucial to understanding the true impact of any intervention. Selecting appropriate measures, relevant to the specific factors of PROs important in the research study will provide valuable data alongside physical health data.

4.
J Biol Chem ; : 107393, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38777143

RESUMO

Protein Tyrosine Phosphatase Non-receptor type 22 (PTPN22) is encoded by a major autoimmunity gene and is a known inhibitor of T cell receptor (TCR) signaling and drug target for cancer immunotherapy. However, little is known about PTPN22 post-translational regulation. Here we characterize a phosphorylation site at Ser325 situated C-terminal to the catalytic domain of PTPN22, and its roles in altering protein function. In human T cells, Ser325 is phosphorylated by Glycogen Synthase Kinase-3 (GSK3) following TCR stimulation, which promotes its TCR-inhibitory activity. Signaling through the major TCR-dependent pathway under PTPN22 control was enhanced by CRISPR/Cas9 mediated suppression of Ser325 phosphorylation and inhibited by mimicking it via glutamic acid substitution. Global phospho-mass spectrometry showed Ser325 phosphorylation state alters downstream transcriptional activity through enrichment of Swi3p, Rsc8p and Moira (SWIRM) domain binding proteins, and next-generation sequencing (NGS) revealed it differentially regulates the expression of chemokines and T cell activation pathways. Moreover, in vitro kinetic data suggest the modulation of activity depends on a cellular context. Finally, we begin to address the structural and mechanistic basis for the influence of Ser325 phosphorylation on the protein's properties by Deuterium Exchange Mass Spectrometry (DX/MS) and Nuclear Magnetic Resonance (NMR) spectroscopy. In conclusion, this study explores the function of a novel phosphorylation site of PTPN22 that is involved in complex regulation of TCR signaling and provides details that might inform the future development of allosteric modulators of PTPN22. Significance statement The tyrosine phosphatase PTPN22 serves as a negative regulator in T cells, and its phosphorylation is a major regulatory process for controlling its function. Here, we uncovered a novel phosphorylation site at Ser325 on PTPN22 that allosterically regulates its activity leading to impaired TCR-dependent pathways. Biophysical methods identify multiple regions affected upon Ser325 phosphorylation, which can be the basis for future mechanistic studies of PTPN22 activators or inhibitors.

5.
Inorg Chem ; 63(20): 9184-9194, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38722234

RESUMO

We report a new nickel hydroxyfluoride diaspore Ni(OH)F prepared using hydrothermal synthesis from NiCl2·6H2O and NaF. Magnetic characterization reveals that, contrary to other reported transition-metal hydroxyfluoride diaspores, Ni(OH)F displays weak ferromagnetism below the magnetic ordering temperature. To understand this difference, neutron diffraction is used to determine the long-range magnetic structure. The magnetic structure is found to be distinct from those reported for other hydroxyfluoride diaspores and shows an antiferromagnetic spin ordering in which ferromagnetic canting is allowed by symmetry. Furthermore, neutron powder diffraction on a deuterated sample, Ni(OD)F, reveals partial anion ordering that is distinctive to what has previously been reported for Co(OH)F and Fe(OH)F. Density functional theory calculations show that OH/F ordering can have a directing influence on the lowest energy magnetic ground state. Our results point toward a subtle interplay between the sign of magnetic exchange interactions, the electronic configuration, and anion disordering.

6.
J Am Chem Soc ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38743719

RESUMO

Electrocatalytic water oxidation is a key transformation in many strategies designed to harness solar energy and store it as chemical fuels. Understanding the mechanism(s) of the best electrocatalysts for water oxidation has been a fundamental chemical challenge for decades. Here, we quantitate evolved dioxygen isotopologue composition via gas-phase EPR spectroscopy to elucidate the mechanisms of water oxidation on metal oxide electrocatalysts with high precision. Isotope fractionation is paired with computational and kinetic modeling, showing that this technique is sensitive enough to differentiate O-O bond-forming steps. Strong agreement between experiment and theory indicates that for the nickel-iron layered double hydroxide─one of the best earth-abundant electrocatalysts to be studied─water oxidation proceeds via a dioxo coupling mechanism to form a side-bound peroxide rather than a hydroxide attack to form an end-bound peroxide.

7.
Plant Commun ; : 100942, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38720463

RESUMO

Feralization is an important evolutionary process, but the mechanisms behind it remain poorly understood. Here, we use the ancient fiber crop, ramie (Boehmeria nivea (L.) Gaudich.) as a model to investigate genomic changes associated with both domestication and fertilization. We first produced a chromosome-scale de novo genome assembly of feral ramie and investigated structural variations between feral and domesticated ramie genomes. Next, 915 accessions from 20 countries were gathered, comprising cultivars, major landraces, feral populations and wild progenitor. Based on whole genome resequencing of these accessions, the most comprehensive ramie genomic variation map to date was constructed. Phylogenetic, demographic, and admixture signal detection analyses indicate that feral ramie is of exoferal or exo-endo origin, i.e., descended from hybridization between domesticated ramie and wild progenitor or ancient landraces. Feral ramie has greater genetic diversity than wild or domesticated ramie, and genomic regions affected by natural selection during feralization are different from those under selection during domestication. Ecological analyses showed that feral and domesticated ramie have similar ecological niches which are substantially different from the niche of the wild progenitor, and three environmental variables were associated with habitat-specific adaptation in feral ramie. Our findings advance our understanding of feralization, providing a scientific basis for the excavation of new crop germplasm resources and offering novel insights into the evolution of feralization in nature.

8.
Nat Genet ; 56(5): 925-937, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38658794

RESUMO

CRISPR base editing screens enable analysis of disease-associated variants at scale; however, variable efficiency and precision confounds the assessment of variant-induced phenotypes. Here, we provide an integrated experimental and computational pipeline that improves estimation of variant effects in base editing screens. We use a reporter construct to measure guide RNA (gRNA) editing outcomes alongside their phenotypic consequences and introduce base editor screen analysis with activity normalization (BEAN), a Bayesian network that uses per-guide editing outcomes provided by the reporter and target site chromatin accessibility to estimate variant impacts. BEAN outperforms existing tools in variant effect quantification. We use BEAN to pinpoint common regulatory variants that alter low-density lipoprotein (LDL) uptake, implicating previously unreported genes. Additionally, through saturation base editing of LDLR, we accurately quantify missense variant pathogenicity that is consistent with measurements in UK Biobank patients and identify underlying structural mechanisms. This work provides a widely applicable approach to improve the power of base editing screens for disease-associated variant characterization.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Genótipo , Fenótipo , RNA Guia de Sistemas CRISPR-Cas , Humanos , Edição de Genes/métodos , RNA Guia de Sistemas CRISPR-Cas/genética , Teorema de Bayes , Receptores de LDL/genética , Células HEK293
9.
Learn Health Syst ; 8(2): e10401, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38633027

RESUMO

Introduction: Rapid translation of research findings into clinical practice through innovation is critical to improve health systems and patient outcomes. Access to efficient systems of learning underpinned with real-time data are the future of healthcare. This type of health system will decrease unwarranted clinical variation, accelerate rapid evidence translation, and improve overall healthcare quality. Methods: This paper aims to describe The HARMONY model (acHieving dAta-dRiven quality iMprovement to enhance frailty Outcomes using a learNing health sYstem), a new frailty learning health system model of implementation science and practice improvement. The HARMONY model provides a prototype for clinical quality registry infrastructure and partnership within health care. Results: The HARMONY model was applied to the Western Sydney Clinical Frailty Registry as the prototype exemplar. The model networks longitudinal frailty data into an accessible and useable format for learning. Creating local capability that networks current data infrastructures to translate and improve quality of care in real-time. Conclusion: This prototype provides a model of registry data feedback and quality improvement processes in an inpatient aged care and rehabilitation hospital setting to help reduce clinical variation, enhance research translation capacity, and improve care quality.

10.
Elife ; 122024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38648100

RESUMO

Genome-wide association studies have revealed >270 loci associated with schizophrenia risk, yet these genetic factors do not seem to be sufficient to fully explain the molecular determinants behind this psychiatric condition. Epigenetic marks such as post-translational histone modifications remain largely plastic during development and adulthood, allowing a dynamic impact of environmental factors, including antipsychotic medications, on access to genes and regulatory elements. However, few studies so far have profiled cell-specific genome-wide histone modifications in postmortem brain samples from schizophrenia subjects, or the effect of antipsychotic treatment on such epigenetic marks. Here, we conducted ChIP-seq analyses focusing on histone marks indicative of active enhancers (H3K27ac) and active promoters (H3K4me3), alongside RNA-seq, using frontal cortex samples from antipsychotic-free (AF) and antipsychotic-treated (AT) individuals with schizophrenia, as well as individually matched controls (n=58). Schizophrenia subjects exhibited thousands of neuronal and non-neuronal epigenetic differences at regions that included several susceptibility genetic loci, such as NRG1, DISC1, and DRD3. By analyzing the AF and AT cohorts separately, we identified schizophrenia-associated alterations in specific transcription factors, their regulatees, and epigenomic and transcriptomic features that were reversed by antipsychotic treatment; as well as those that represented a consequence of antipsychotic medication rather than a hallmark of schizophrenia in postmortem human brain samples. Notably, we also found that the effect of age on epigenomic landscapes was more pronounced in frontal cortex of AT-schizophrenics, as compared to AF-schizophrenics and controls. Together, these data provide important evidence of epigenetic alterations in the frontal cortex of individuals with schizophrenia, and remark for the first time on the impact of age and antipsychotic treatment on chromatin organization.


Assuntos
Antipsicóticos , Epigênese Genética , Lobo Frontal , Esquizofrenia , Humanos , Esquizofrenia/genética , Esquizofrenia/tratamento farmacológico , Esquizofrenia/metabolismo , Antipsicóticos/farmacologia , Antipsicóticos/uso terapêutico , Lobo Frontal/metabolismo , Lobo Frontal/efeitos dos fármacos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Epigenômica , Idoso , Histonas/metabolismo
11.
Environ Res ; 252(Pt 2): 118912, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38615789

RESUMO

BACKGROUND: Polychlorinated biphenyls (PCBs), extensively used in various products, prompt ongoing concern despite reduced exposure since the 1970s. This systematic review explores prenatal PCB and hydroxylated metabolites (OH-PCBs) exposure's association with child neurodevelopment. Encompassing cognitive, motor development, behavior, attention, ADHD, and ASD risks, it also evaluates diverse methodological approaches in studies. METHODS: PubMed, Embase, PsycINFO, and Web of Science databases were searched through August 23, 2023, by predefined search strings. Peer-reviewed studies published in English were included. The inclusion criteria were: (i) PCBs/OH-PCBs measured directly in maternal and cord blood, placenta or breast milk collected in the perinatal period; (ii) outcomes of cognitive development, motor development, attention, behavior, attention-deficit/hyperactivity disorder (ADHD), and autism spectrum disorder (ASD) among children≤18 years old. Quality assessment followed the National Heart, Lung, and Blood Institute's tool. RESULTS: Overall, 87 studies were included in this review. We found evidence for the association between perinatal PCB exposure and adverse cognitive development and attention issues in middle childhood. There appeared to be no or negligible link between perinatal PCB exposure and early childhood motor development or the risk of ADHD/ASD. There was an indication of a sex-specific association with worse cognition and attention scores among boys. Some individual studies suggested a possible association between prenatal exposure to OH-PCBs and neurodevelopmental outcomes. There was significant heterogeneity between the studies in exposure markers, exposure assessment timing, outcome assessment, and statistical analysis. CONCLUSIONS: Significant methodological, clinical and statistical heterogeneity existed in the included studies. Adverse effects on cognitive development and attention were observed in middle childhood. Little or no apparent link on both motor development and risk of ADHD/ASD was observed in early childhood. Inconclusive evidence prevailed regarding other neurodevelopmental aspects due to limited studies. Future research could further explore sex-specific associations and evaluate associations at lower exposure levels post-PCB ban in the US. It should also consider OH-PCB metabolites, co-pollutants, mixtures, and their potential interactions.

12.
J Clin Med ; 13(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38610721

RESUMO

In hyperglycemia, the serum sodium concentration ([Na]S) receives influences from (a) the fluid exit from the intracellular compartment and thirst, which cause [Na]S decreases; (b) osmotic diuresis with sums of the urinary sodium plus potassium concentration lower than the baseline euglycemic [Na]S, which results in a [Na]S increase; and (c), in some cases, gains or losses of fluid, sodium, and potassium through the gastrointestinal tract, the respiratory tract, and the skin. Hyperglycemic patients with hypernatremia have large deficits of body water and usually hypovolemia and develop severe clinical manifestations and significant mortality. To assist with the correction of both the severe dehydration and the hypovolemia, we developed formulas computing the fractional losses of the body water and monovalent cations in hyperglycemia. The formulas estimate varying losses between patients with the same serum glucose concentration ([Glu]S) and [Na]S but with different sums of monovalent cation concentrations in the lost fluids. Among subjects with the same [Glu]S and [Na]S, those with higher monovalent cation concentrations in the fluids lost have higher fractional losses of body water. The sum of the monovalent cation concentrations in the lost fluids should be considered when computing the volume and composition of the fluid replacement for hyperglycemic syndromes.

13.
Sci Rep ; 14(1): 9013, 2024 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641713

RESUMO

Deep learning algorithms have demonstrated remarkable potential in clinical diagnostics, particularly in the field of medical imaging. In this study, we investigated the application of deep learning models in early detection of fetal kidney anomalies. To provide an enhanced interpretation of those models' predictions, we proposed an adapted two-class representation and developed a multi-class model interpretation approach for problems with more than two labels and variable hierarchical grouping of labels. Additionally, we employed the explainable AI (XAI) visualization tools Grad-CAM and HiResCAM, to gain insights into model predictions and identify reasons for misclassifications. The study dataset consisted of 969 ultrasound images from unique patients; 646 control images and 323 cases of kidney anomalies, including 259 cases of unilateral urinary tract dilation and 64 cases of unilateral multicystic dysplastic kidney. The best performing model achieved a cross-validated area under the ROC curve of 91.28% ± 0.52%, with an overall accuracy of 84.03% ± 0.76%, sensitivity of 77.39% ± 1.99%, and specificity of 87.35% ± 1.28%. Our findings emphasize the potential of deep learning models in predicting kidney anomalies from limited prenatal ultrasound imagery. The proposed adaptations in model representation and interpretation represent a novel solution to multi-class prediction problems.


Assuntos
Aprendizado Profundo , Nefropatias , Sistema Urinário , Gravidez , Feminino , Humanos , Ultrassonografia Pré-Natal/métodos , Diagnóstico Pré-Natal/métodos , Nefropatias/diagnóstico por imagem , Sistema Urinário/anormalidades
14.
Hypertension ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38660784

RESUMO

BACKGROUND: Chronic hypertension is an established long-term risk factor for major adverse cardiovascular events (MACEs). However, little is known about short-term MACE risk after hypertensive urgency, defined as an episode of acute severe hypertension without evidence of target-organ damage. We sought to evaluate the short-term risk of MACE after an emergency department (ED) visit for hypertensive urgency resulting in discharge to home. METHODS: We performed a case-crossover study using deidentified administrative claims data. Our case periods were 1-week intervals from 0 to 12 weeks before hospitalization for MACE. We compared ED visits for hypertensive urgency during these case periods versus equivalent control periods 1 year earlier. Hypertensive urgency and MACE components were all ascertained using previously validated International Classification of Diseases, Tenth Revision Clinical Modification codes. We used McNemar test for matched data to calculate risk ratios. RESULTS: Among 2 225 722 patients with MACE, 1 893 401 (85.1%) had a prior diagnosis of hypertension. There were 4644 (0.2%) patients who had at least 1 ED visit for hypertensive urgency during the 12 weeks preceding their MACE hospitalization. An ED visit for hypertensive urgency was significantly more common in the first week before MACE compared with the same chronological week 1 year earlier (risk ratio, 3.5 [95% CI, 2.9-4.2]). The association between hypertensive urgency and MACE decreased in magnitude with increasing temporal distance from MACE and was no longer significant by 11 weeks before MACE (risk ratio, 1.2 [95% CI, 0.99-1.6]). CONCLUSIONS: ED visits for hypertensive urgency were associated with a substantially increased short-term risk of subsequent MACE.

15.
Radiographics ; 44(5): e230087, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38573816

RESUMO

Monogenic cerebral vasculopathy is a rare but progressively recognizable cause of pediatric cerebral vasculopathy manifesting as early as fetal life. These monogenic cerebral vasculopathies can be silent or manifest variably as fetal or neonatal distress, neurologic deficit, developmental delay, cerebral palsy, seizures, or stroke. The radiologic findings can be nonspecific, but the presence of disease-specific cerebral and extracerebral imaging features can point to a diagnosis and guide genetic testing, allowing targeted treatment. The authors review the existing literature describing the frequently encountered and rare monogenic cerebral vascular disorders affecting young patients and describe the relevant pathogenesis, with an attempt to categorize them based on the defective step in vascular homeostasis and/or signaling pathways and characteristic cerebrovascular imaging findings. The authors also highlight the role of imaging and a dedicated imaging protocol in identification of distinct cerebral and extracerebral findings crucial in the diagnostic algorithm and selection of genetic testing. Early and precise recognition of these entities allows timely intervention, preventing or delaying complications and thereby improving quality of life. It is also imperative to identify the specific pathogenic variant and pattern of inheritance for satisfactory genetic counseling and care of at-risk family members. Last, the authors present an image-based approach to these young-onset monogenic cerebral vasculopathies that is guided by the size and predominant radiologic characteristics of the affected vessel with reasonable overlap. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.


Assuntos
Qualidade de Vida , Acidente Vascular Cerebral , Recém-Nascido , Humanos , Criança , Diagnóstico por Imagem , Testes Genéticos
17.
Br J Cancer ; 130(10): 1659-1669, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38480935

RESUMO

BACKGROUND: Vestibular schwannomas (VSs) remain a challenge due to their anatomical location and propensity to growth. Macrophages are present in VS but their roles in VS pathogenesis remains unknown. OBJECTIVES: The objective was to assess phenotypic and functional profile of macrophages in VS with single-cell RNA sequencing (scRNAseq). METHODS: scRNAseq was carried out in three VS samples to examine characteristics of macrophages in the tumour. RT-qPCR was carried out on 10 VS samples for CD14, CD68 and CD163 and a panel of macrophage-associated molecules. RESULTS: scRNAseq revealed macrophages to be a major constituent of VS microenvironment with three distinct subclusters based on gene expression. The subclusters were also defined by expression of CD163, CD68 and IL-1ß. AREG and PLAUR were expressed in the CD68+CD163+IL-1ß+ subcluster, PLCG2 and NCKAP5 were expressed in CD68+CD163+IL-1ß- subcluster and AUTS2 and SPP1 were expressed in the CD68+CD163-IL-1ß+ subcluster. RT-qPCR showed expression of several macrophage markers in VS of which CD14, ALOX15, Interleukin-1ß, INHBA and Colony Stimulating Factor-1R were found to have a high correlation with tumour volume. CONCLUSIONS: Macrophages form an important component of VS stroma. scRNAseq reveals three distinct subsets of macrophages in the VS tissue which may have differing roles in the pathogenesis of VS.


Assuntos
Macrófagos , Neuroma Acústico , Análise de Sequência de RNA , Análise de Célula Única , Humanos , Neuroma Acústico/genética , Neuroma Acústico/patologia , Neuroma Acústico/metabolismo , Análise de Célula Única/métodos , Macrófagos/metabolismo , Macrófagos/patologia , Microambiente Tumoral/genética , Feminino , Masculino , Pessoa de Meia-Idade , Antígenos CD/genética , Antígenos de Diferenciação Mielomonocítica/genética , Antígenos de Diferenciação Mielomonocítica/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo
18.
Chem Sci ; 15(12): 4374-4385, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38516069

RESUMO

We report the first synthesis of the mixed-metal chabazite-type AlxGa1-xPO4-34(mim) solid solution, containing 1-methylimidazolium, mim, as structure directing agent (SDA), from the parent mixed-metal oxide solid solution, γ-(AlxGa1-x)2O3. This hitherto unreported family of materials exhibits complex disorder, arising from the possible distributions of cations over available sites, the orientation of the SDA and the presence of variable amounts of water, which provides a prototype for understanding structural subtleties in nanoporous materials. In the as-made forms of the phosphate frameworks, there are three crystallographically distinct metal sites: two tetrahedral MO4 and one octahedral MO4F2 (M = Al, Ga). A combination of solid-state NMR spectroscopy and periodic DFT calculations reveals that the octahedral site is preferentially occupied by Al and the tetrahedral sites by Ga, leading to a non-random distribution of cations within the framework. Upon calcination to the AlxGa1-xPO4-34 framework, all metal sites are tetrahedral and crystallographically equivalent in the average R3̄ symmetry. The cation distribution was explored by 31P solid-state NMR spectroscopy, and it is shown that the non-random distribution demonstrated to exist in the as-made materials would be expected to give remarkably similar patterns of peak intensities to a random distribution owing to the change in average symmetry in the calcined materials.

19.
Neurology ; 102(8): e209204, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38531010

RESUMO

BACKGROUND AND OBJECTIVES: To determine the prevalence of silent brain infarction (SBI) and cerebral small vessel disease (CSVD) in adults with atrial fibrillation (AF), coronary artery disease, heart failure or cardiomyopathy, heart valve disease, and patent foramen ovale (PFO), with comparisons between those with and without recent stroke and an exploration of associations between heart disease and SBI/CSVD. METHODS: Medline, Embase, and Cochrane Library were systematically searched for hospital-based or community-based studies reporting SBI/CSVD in people with heart disease. Data were extracted from eligible studies. Outcomes were SBI (primary) and individual CSVD subtypes. Summary prevalence (95% confidence intervals [CIs]) were obtained using random-effects meta-analysis. Pooled prevalence ratios (PRs) (95% CI) were calculated to compare those with heart disease with available control participants without heart disease from studies. RESULTS: A total of 221 observational studies were included. In those with AF, the prevalence was 36% (31%-41%) for SBI (70 studies, N = 13,589), 25% (19%-31%) for lacune (26 studies, N = 7,172), 62% (49%-74%) for white matter hyperintensity/hypoattenuation (WMH) (34 studies, N = 7,229), and 27% (24%-30%) for microbleed (44 studies, N = 13,654). Stratification by studies where participants with recent stroke were recruited identified no differences in the prevalence of SBI across subgroups (phomogeneity = 0.495). Results were comparable across participants with different heart diseases except for those with PFO, in whom there was a lower prevalence of SBI [21% (13%-30%), 11 studies, N = 1,053] and CSVD. Meta-regressions after pooling those with any heart disease identified associations of increased (study level) age and hypertensives with more SBIs and WMH (pregression <0.05). There was no evidence of a difference in the prevalence of microbleed between those with and without heart disease (PR [95% CI] 1.1 [0.7-1.7]), but a difference was seen in the prevalence of SBI and WMH (PR [95% CI] 2.3 [1.6-3.1] and 1.7 [1.1-2.6], respectively). DISCUSSION: People with heart disease have a high prevalence of SBI (and CSVD), which is similar in those with vs without recent stroke. More research is required to assess causal links and implications for management. TRIAL REGISTRATION INFORMATION: PROSPERO CRD42022378272 (crd.york.ac.uk/PROSPERO/).


Assuntos
Doenças de Pequenos Vasos Cerebrais , Cardiopatias , Acidente Vascular Cerebral , Adulto , Humanos , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Infarto Encefálico/etiologia , Doenças de Pequenos Vasos Cerebrais/complicações , Cardiopatias/complicações , Hemorragia Cerebral/complicações
20.
Br J Clin Pharmacol ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38509766

RESUMO

With population ageing, drug trials are increasingly turning their attention to including older, frailer people. This review aimed to provide an overview of how frailty was assessed in published studies related to clinical pharmacological trials, and on the interaction of frailty on the efficacy of the treatments. We searched MEDLINE, EMBASE and Cochrane for clinical drug trials in older people. A total of 4031 abstracts were screened and 17 relevant studies were included in this review. We summarized the findings of these 17 trials into five main clinical areas: cardiovascular (eight studies), cognition (one study), vaccination (two studies), cancer (four studies) and other (two studies). Frailty was assessed retrospectively in most of the studies. Frailty was treated as an ordinal variable (with different levels of frailty) or binary variable (frail/non-frail) using cut-offs in some studies, and as a continuous in some other studies. The effect of frailty on the treatment efficacy was not consistent among the studies. While several trials, such as the Action in Diabetes and Vascular Disease-Preterax and Diamicron Modified Release Controlled Evaluation trials, the Systolic Blood Pressure Intervention Trial and the Aspirin in Reducing Events in the Elderly trial, showed some reduced effects of the treatment in frail patients, most of the trials showed that the benefits of the treatment are not affected by frailty. Some trials even showed that the benefits of the treatment were more significant in frailer patients (the Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure and the Dapagliflozin Evaluation to Improve the Lives of Patients with Preserved Ejection Fraction Heart Failure trials). The results of this review suggest that routine measurement of frailty in participants in clinical drug trials would improve our knowledge of the effect of treatment in the frail and identify those who have more or least to gain from treatment.

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