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1.
Proc Natl Acad Sci U S A ; 121(8): e2308729121, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38354265

RESUMEN

On cooling from the melt, plutonium (Pu) undergoes a series of structural transformations accompanied by a ≈ 28% reduction in volume from its δ phase to its α phase at low temperatures. While Pu's partially filled 5f-electron shells are known to be involved, their precise role in the transformations has remained unclear. By using calorimetry measurements on α-Pu and gallium-stabilized δ-Pu combined with resonant ultrasound and X-ray scattering data to account for the anomalously large softening of the lattice with temperature, we show here that the difference in electronic entropy between the α and δ phases dominates over the difference in phonon entropy. Rather than finding an electronic specific heat characteristic of broad f-electron bands in α-Pu, as might be expected to occur within a Kondo collapsed phase in analogy with cerium, we find it to be indicative of flatter subbands. An important role played by Pu's 5f electrons in the formation of its larger unit cell α phase comprising inequivalent lattice sites and varying bond lengths is therefore suggested.

2.
Brain ; 146(1): 252-265, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-35136951

RESUMEN

Duchenne muscular dystrophy (DMD) is characterized by loss of dystrophin in muscle, however patients also have variable degree of intellectual disability and neurobehavioural co-morbidities. In contrast to muscle, in which a single full-length dystrophin isoform (Dp427) is produced, multiple isoforms are produced in the brain, and their deficiency accounts for the variability of CNS manifestations, with increased risk of comorbidities in patients carrying mutations affecting the 3' end of the gene, which disrupt expression of shorter Dp140 and Dp71 isoforms. A mouse model (mdx mouse) lacks Dp427 in muscle and CNS and exhibits exaggerated startle responses to threat, linked to the deficiency of dystrophin in limbic structures such as the amygdala, which normalize with postnatal brain dystrophin-restoration therapies. A pathological startle response is not a recognized feature of DMD, and its characterization has implications for improved clinical management and translational research. To investigate startle responses in DMD, we used a novel fear-conditioning task in an observational study of 56 males aged 7-12 years (31 affected boys, mean age 9.7 ± 1.8 years; 25 controls, mean age 9.6 ± 1.4 years). Trials of two neutral visual stimuli were presented to participants: one 'safe' cue presented alone; one 'threat' cue paired with an aversive noise to enable conditioning of physiological startle responses (skin conductance response and heart rate). Retention of conditioned physiological responses was subsequently tested by presenting both cues without the aversive noise in an 'Extinction' phase. Primary outcomes were the initial unconditioned skin conductance and change in heart rate responses to the aversive 'threat' and acquisition and retention of conditioned responses after conditioning. Secondary and exploratory outcomes were neuropsychological measures and genotype associations. The mean unconditioned skin conductance response was greater in the DMD group than controls [mean difference 3.0 µS (1.0, 5.1); P = 0.004], associated with a significant threat-induced bradycardia only in the patient group [mean difference -8.7 bpm (-16.9, -0.51); P = 0.04]. Participants with DMD found the task more aversive than controls, with increased early termination rates during the Extinction phase (26% of DMD group versus 0% of controls; P = 0.007). This study provides the first evidence that boys with DMD show similar increased unconditioned startle responses to threat to the mdx mouse, which in the mouse respond to brain dystrophin restoration. Our study provides new insights into the neurobiology underlying the complex neuropsychiatric co-morbidities in DMD and defines an objective measure of this CNS phenotype, which will be valuable for future CNS-targeted dystrophin-restoration studies.


Asunto(s)
Distrofina , Distrofia Muscular de Duchenne , Masculino , Ratones , Animales , Distrofina/genética , Distrofina/metabolismo , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/patología , Reflejo de Sobresalto , Ratones Endogámicos mdx , Encéfalo/patología , Biomarcadores/metabolismo , Isoformas de Proteínas/metabolismo
3.
Proc Natl Acad Sci U S A ; 118(7)2021 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-33563764

RESUMEN

A central question in the underdoped cuprates pertains to the nature of the pseudogap ground state. A conventional metallic ground state of the pseudogap region has been argued to host quantum oscillations upon destruction of the superconducting order parameter by modest magnetic fields. Here, we use low applied measurement currents and millikelvin temperatures on ultrapure single crystals of underdoped [Formula: see text] to unearth an unconventional quantum vortex matter ground state characterized by vanishing electrical resistivity, magnetic hysteresis, and nonohmic electrical transport characteristics beyond the highest laboratory-accessible static fields. A model of the pseudogap ground state is now required to explain quantum oscillations that are hosted by the bulk quantum vortex matter state without experiencing sizable additional damping in the presence of a large maximum superconducting gap; possibilities include a pair density wave.

4.
Neuroimage ; 274: 120124, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37084927

RESUMEN

The brain has a unique macroscopic waste clearance system, termed the glymphatic system which utilises perivascular tunnels surrounded by astroglia to promote cerebrospinal-interstitial fluid exchange. Rodent studies have demonstrated a marked increase in glymphatic clearance during sleep which has been linked to a sleep-induced expansion of the extracellular space and concomitant reduction in intracellular volume. However, despite being implicated in the pathophysiology of multiple human neurodegenerative disorders, non-invasive techniques for imaging glymphatic clearance in humans are currently limited. Here we acquired multi-shell diffusion weighted MRI (dwMRI) in twenty-one healthy young participants (6 female, 22.3 ± 3.2 years) each scanned twice, once during wakefulness and once during sleep induced by a combination of one night of sleep deprivation and 10 mg of the hypnotic zolpidem 30 min before scanning. To capture hypothesised sleep-associated changes in intra/extracellular space, dwMRI were analysed using higher order diffusion modelling with the prediction that sleep-associated increases in interstitial (extracellular) fluid volume would result in a decrease in diffusion kurtosis, particularly in areas associated with slow wave generation at the onset of sleep. In line with our hypothesis, we observed a global reduction in diffusion kurtosis (t15=2.82, p = 0.006) during sleep as well as regional reductions in brain areas associated with slow wave generation during early sleep and default mode network areas that are highly metabolically active during wakefulness. Analysis with a higher-order representation of diffusion (MAP-MRI) further indicated that changes within the intra/extracellular domain rather than membrane permeability likely underpin the observed sleep-associated decrease in kurtosis. These findings identify higher-order modelling of dwMRI as a potential new non-invasive method for imaging glymphatic clearance and extend rodent findings to suggest that sleep is also associated with an increase in interstitial fluid volume in humans.


Asunto(s)
Encéfalo , Sistema Glinfático , Humanos , Femenino , Encéfalo/diagnóstico por imagen , Sistema Glinfático/diagnóstico por imagen , Sistema Glinfático/fisiología , Imagen por Resonancia Magnética/métodos , Sueño , Imagen de Difusión por Resonancia Magnética
5.
Brain Behav Immun ; 111: 320-327, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37105388

RESUMEN

BACKGROUND: Inflammation rapidly reorients motivational state, mood is impaired, pleasurable activities avoided and sensitivity to negative stimuli enhanced. When sustained, this can precipitate major depressive episodes. In humans, this has been linked to opposing actions of inflammation on striatal/insula reward/punishment learning signals while in rodents, motivational impairments can be attenuated with minocycline, implicating a mechanistic role for microglia. Here we investigated whether minocycline also inhibits the reorienting effects of lipopolysaccharide (LPS) on reward/punishment sensitivity in humans. Methods Using a crossover design, fifteen healthy volunteers underwent two experimental sessions in which they each received LPS (1 ng/kg) and placebo. Half (N = 8) received minocycline (100 mg bd) and half (N = 7) an identical looking placebo for 3½ days before each session. Six hours post-injection participants completed a probabilistic instrumental learning task in which they had to learn to select high probability reward (win £1) and avoid high probability punishment (lose £1) stimuli to maximise their gains and minimize losses. Physiological and sickness responses were sampled hourly and blood sampled at baseline, 3 and 6 h post-injection. Results LPS induced robust peripheral physiological: temperature, heart rate and immune: differential white cell, IL-6, TNF-α, IL-8, IL-10 responses (all condition × time interactions: p < 0.005), none were significantly modulated by minocycline (p > 0.1). LPS also biased behavior, enhancing punishment compared with reward sensitivity (F(1,13) = 6.10, p = 0.028). Minocycline significantly attenuated this inflammation-induced shift in reward versus punishment sensitivity (F(1,13) = 4.28, p = 0.033). Conclusions These data replicate the previous finding that systemic inflammation rapidly impairs sensitivity to rewards versus punishments in humans and extend this by implicating activated microglia in this acute motivational reorientation with implications for the development of microglial-targeted immune-modulatory therapies in depression.


Asunto(s)
Trastorno Depresivo Mayor , Castigo , Humanos , Minociclina/farmacología , Lipopolisacáridos/farmacología , Recompensa , Inflamación/tratamiento farmacológico
6.
Proc Natl Acad Sci U S A ; 117(9): 4480-4485, 2020 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-32071232

RESUMEN

Plutonium metal exhibits an anomalously large softening of its bulk modulus at elevated temperatures that is made all the more extraordinary by the finding that it occurs irrespective of whether the thermal expansion coefficient is positive, negative, or zero-representing an extreme departure from conventional Grüneisen scaling. We show here that the cause of this softening is the compressibility of plutonium's thermally excited electronic configurations, which has thus far not been considered in thermodynamic models. We show that when compressible electronic configurations are thermally activated, they invariably give rise to a softening of the bulk modulus regardless of the sign of their contribution to the thermal expansion. The electronically driven softening of the bulk modulus is shown to be in good agreement with elastic moduli measurements performed on the gallium-stabilized δ phase of plutonium over a range of temperatures and compositions and is shown to grow rapidly at small concentrations of gallium and at high temperatures, where it becomes extremely sensitive to hydrostatic pressure.

7.
Proc Natl Acad Sci U S A ; 117(18): 9782-9786, 2020 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-32317380

RESUMEN

High magnetic fields have revealed a surprisingly small Fermi surface in underdoped cuprates, possibly resulting from Fermi-surface reconstruction due to an order parameter that breaks translational symmetry of the crystal lattice. A crucial issue concerns the doping extent of such a state and its relationship to the principal pseudogap and superconducting phases. We employ pulsed magnetic-field measurements on the cuprate [Formula: see text]Cu[Formula: see text] to identify signatures of Fermi-surface reconstruction from a sign change of the Hall effect and a peak in the temperature-dependent planar resistivity. We trace the termination of Fermi-surface reconstruction to two hole concentrations where the superconducting upper critical fields are found to be enhanced. One of these points is associated with the pseudogap endpoint near optimal doping. These results connect the Fermi-surface reconstruction to both superconductivity and the pseudogap phenomena.

8.
Med Teach ; 45(12): 1349-1356, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37210674

RESUMEN

It is recognised that simulation-based education can be stressful, and this can impact negatively on learning. A fundamental aspect of facilitating simulation is creating a safe educational environment. Edmondson's seminal work on creating psychological safety among interpersonal teams has been embraced by the healthcare simulation community. Psychological safety is an underpinning philosophy for creating simulation experiences in which learners can develop within a stimulating and challenging yet supportive social atmosphere. Through careful design and thoughtful delivery, the introductory phase of simulation, the pre-briefing, can effectively prepare learners for simulation, reduce learner anxiety, and promote psychological safety, to enhance learning experiences. These twelve tips provide guidance for conducting a pre-brief and promoting a psychologically safe environment for simulation-based education.


Asunto(s)
Educación Médica , Seguridad Psicológica , Humanos , Aprendizaje , Escolaridad , Educación Médica/métodos , Atención a la Salud
9.
Psychol Med ; 52(14): 3289-3296, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-33731235

RESUMEN

BACKGROUND: Depression and overweight are each associated with abnormal immune system activation. We sought to disentangle the extent to which depressive symptoms and overweight status contributed to increased inflammation and abnormal cortisol levels. METHODS: Participants were recruited through the Wellcome Trust NIMA Consortium. The sample of 216 participants consisted of 69 overweight patients with depression; 35 overweight controls; 55 normal-weight patients with depression and 57 normal-weight controls. Peripheral inflammation was measured as high-sensitivity C-Reactive Protein (hsCRP) in serum. Salivary cortisol was collected at multiple points throughout the day to measure cortisol awakening response and diurnal cortisol levels. RESULTS: Overweight patients with depression had significantly higher hsCRP compared with overweight controls (p = 0.042), normal-weight depressed patients (p < 0.001) and normal-weight controls (p < 0.001), after controlling for age and gender. Multivariable logistic regression showed that comorbid depression and overweight significantly increased the risk of clinically elevated hsCRP levels ⩾3 mg/L (OR 2.44, 1.28-3.94). In a separate multivariable logistic regression model, overweight status contributed most to the risk of having hsCRP levels ⩾3 mg/L (OR 1.52, 0.7-2.41), while depression also contributed a significant risk (OR 1.09, 0.27-2). There were no significant differences between groups in cortisol awakening response and diurnal cortisol levels. CONCLUSION: Comorbid depression and overweight status are associated with increased hsCRP, and the coexistence of these conditions amplified the risk of clinically elevated hsCRP levels. Overweight status contributed most to the risk of clinically elevated hsCRP levels, but depression also contributed to a significant risk. We observed no differences in cortisol levels between groups.


Asunto(s)
Hidrocortisona , Sobrepeso , Humanos , Sobrepeso/epidemiología , Hidrocortisona/metabolismo , Proteína C-Reactiva/análisis , Depresión/epidemiología , Inflamación , Sistema Hipófiso-Suprarrenal/metabolismo , Saliva/química , Sistema Hipotálamo-Hipofisario/metabolismo
10.
Brain Behav Immun ; 99: 256-265, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34673176

RESUMEN

BACKGROUND: Low-dose lipopolysaccharide (LPS) is a well-established experimental method for inducing systemic inflammation and shown by microscopy to activate microglia in rodents. Currently, techniques for in-vivo imaging of glia in humans are limited to TSPO (Translocator protein) PET, which is expensive, methodologically challenging, and has poor cellular specificity. Diffusion-weighted magnetic resonance spectroscopy (DW-MRS) sensitizes MR spectra to diffusion of intracellular metabolites, potentially providing cell-specific information about cellular morphology. In this preliminary study, we applied DW-MRS to measure changes in the apparent diffusion coefficients (ADC) of glial and neuronal metabolites to healthy participants who underwent an LPS administration protocol. We hypothesized that the ADC of glial metabolites will be selectively modulated by LPS-induced glial activation. METHODS: Seven healthy male volunteers, (mean 25.3 ± 5.9 years) were each tested in two separate sessions once after LPS (1 ng/Kg intravenously) and once after placebo (saline). Physiological responses were monitored during each session and serial blood samples and Profile of Mood States (POMS) completed to quantify white blood cell (WBC), cytokine and mood responses. DW-MRS data were acquired 5-5½ hours after injection from two brain regions: grey matter in the left thalamus, and frontal white matter. RESULTS: Body temperature, heart rate, WBC and inflammatory cytokines were significantly higher in the LPS compared to the placebo condition (p < 0.001). The ADC of the glial metabolite choline (tCho) was also significantly increased after LPS administration compared to placebo (p = 0.008) in the thalamus which scaled with LPS-induced changes in POMS total and negative mood (Adj R2 = 0.83; p = 0.004). CONCLUSIONS: DW-MRS may be a powerful new tool sensitive to glial cytomorphological changes in grey matter induced by systemic inflammation.


Asunto(s)
Imagen de Difusión por Resonancia Magnética , Lipopolisacáridos , Encéfalo/metabolismo , Colina/metabolismo , Colina/farmacología , Imagen de Difusión por Resonancia Magnética/métodos , Humanos , Lipopolisacáridos/metabolismo , Lipopolisacáridos/farmacología , Espectroscopía de Resonancia Magnética/métodos , Masculino , Neuroglía/metabolismo , Receptores de GABA/metabolismo
11.
Mol Psychiatry ; 26(9): 5150-5160, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-32457424

RESUMEN

A third of patients receiving Interferon-α (IFN-α) treatment for Hepatitis-C develop major depressive disorder (MDD). Conversely, anti-Tumor Necrosis Factor (TNF) therapies improve depression providing key empirical support for the "inflammatory theory" of depression. Heightened amygdala reactivity (particularly to negatively valanced stimuli) is a consistent finding within MDD; can predict treatment efficacy and reverses following successful treatment. However, whether IFN-α and anti-TNF enhance/attenuate depressive symptoms through modulation of amygdala emotional reactivity is unknown. Utilizing a prospective study design, we recruited 30 patients (mean 48.0 ± 10.5 years, 21 male) initiating IFN-α treatment for Hepatitis-C and 30 (mean 50.4 ± 15.7 years, 10 male) anti-TNF therapy for inflammatory arthritis. All completed an emotional face-processing task during fMRI and blood sampling before and after their first IFN-α (4-h) or anti-TNF (24-h) injection and follow-up psychiatric assessments for 3 months of treatment. IFN-α significantly increased depression symptoms (Hamilton Depression Rating Scale HAM-D) at 4 weeks (p < 0.001) but not 4-h after first dose (p > 0.1). Conversely, anti-TNF significantly improved depressive symptoms (Hospital Anxiety and Depression Rating Scale HADS) at both 24-h (P = 0.015) and 12 weeks (p = 0.018). In support of our a-priori hypothesis, both IFN-α and anti-TNF significantly modulated amygdala reactivity with IFN-α acutely enhancing right amygdala responses to sad (compared with neutral) faces (p = 0.032) and anti-TNF conversely decreasing right amygdala reactivity (across emotional valence) (p = 0.033). Furthermore, these changes predicted IFN-induced increases in HAM-D 4 weeks later (R2 = 0.17, p = 0.022) and anti-TNF-associated decreases in HADS at 24-h (R2 = 0.23, p = 0.01) suggesting that actions of systemic inflammation on amygdala emotional reactivity play a mechanistic role in inflammation-associated depressive symptoms.


Asunto(s)
Depresión , Trastorno Depresivo Mayor , Amígdala del Cerebelo , Depresión/tratamiento farmacológico , Humanos , Interferón-alfa , Masculino , Estudios Prospectivos , Inhibidores del Factor de Necrosis Tumoral
12.
Mol Psychiatry ; 26(12): 7346-7354, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34535766

RESUMEN

Inflammation is associated with depressive symptoms and innate immune mechanisms are likely causal in some cases of major depression. Systemic inflammation also perturbs brain function and microstructure, though how these are related remains unclear. We recruited N = 46 healthy controls, and N = 83 depressed cases stratified by CRP (> 3 mg/L: N = 33; < 3 mg/L: N = 50). All completed clinical assessment, venous blood sampling for C-reactive protein (CRP) assay, and brain magnetic resonance imaging (MRI). Micro-structural MRI parameters including proton density (PD), a measure of tissue water content, were measured at 360 cortical and 16 subcortical regions. Resting-state fMRI time series were correlated to estimate functional connectivity between individual regions, as well as the sum of connectivity (weighted degree) of each region. Multiple tests for regional analysis were controlled by the false discovery rate (FDR = 5%). We found that CRP was significantly associated with PD in precuneus, posterior cingulate cortex (pC/pCC) and medial prefrontal cortex (mPFC); and with functional connectivity between pC/pCC, mPFC and hippocampus. Depression was associated with reduced weighted degree of pC/pCC, mPFC, and other nodes of the default mode network (DMN). Thus CRP-related increases in proton density-a plausible marker of extracellular oedema-and changes in functional connectivity were anatomically co-localised with DMN nodes that also demonstrated significantly reduced hubness in depression. We suggest that effects of peripheral inflammation on DMN node micro-structure and connectivity may mediate inflammatory effects on depression.


Asunto(s)
Encéfalo , Depresión , Mapeo Encefálico , Humanos , Inflamación , Imagen por Resonancia Magnética/métodos , Vías Nerviosas
13.
High Educ (Dordr) ; 83(2): 357-378, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33362292

RESUMEN

Life outcomes for people who spent time in the care of the state as children ('care-experienced') are known to be significantly lower, on average, than for the general population. The reasons for this are complex and multidimensional, relating to social upheaval, disrupted schooling, mental and physical health issues and societal stigmatisation. Previous studies across several countries have demonstrated that they are significantly less likely to participate in higher education and more likely to withdraw early. However, little is currently known about their outcomes after graduation. This paper therefore explores the initial outcomes for the 1,010 full-time students identified as care-experienced within the cohort graduating from an undergraduate degree programme in the UK in 2016/17-the most recent year for which data are available. They were found to be slightly more likely to be unemployed and less likely to be in work (and particularly professional work) than their peers, but, conversely, more likely to be studying. These differences largely disappeared once background educational and demographic factors were controlled. The paper discusses the relationship between care-experience and other sites of inequality, concluding that care-experienced graduates are crucially over-represented in groups that are disadvantaged in the graduate labour market-e.g. by ethnicity, disability or educational history. This intersectional inequality largely explains their lower graduate outcomes. While there are important limitations with the data available, this speaks for the transformational potential of higher education in enabling care-experienced graduates to transcend childhood adversity. Recommendations for national policy and local practices conclude the paper.

14.
J Physiol ; 599(11): 2851-2868, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33709461

RESUMEN

KEY POINTS: We report a novel method for the transient expression of SARS-CoV-2 envelope (E) protein in intracellular organelles and the plasma membrane of mammalian cells and Xenopus oocytes. Intracellular expression of SARS-CoV-2 E protein increases intra-Golgi pH. By targeting the SARS-CoV-2 E protein to the plasma membrane, we show that it forms a cation channel, viroporin, that is modulated by changes of pH. This method for studying the activity of viroporins may facilitate screening for new antiviral drugs to identify novel treatments for COVID-19. ABSTRACT: The envelope (E) protein of coronaviruses such as SARS-CoV-1 is proposed to form an ion channel or viroporin that participates in viral propagation and pathogenesis. Here we developed a technique to study the E protein of SARS-CoV-2 in mammalian cells by directed targeting using a carboxyl-terminal fluorescent protein tag, mKate2. The wild-type SARS-CoV-2 E protein can be trafficked to intracellular organelles, notably the endoplasmic reticulum-Golgi intermediate complex, where its expression increases pH inside the organelle. We also succeeded in targeting SARS-CoV-2 E to the plasma membrane, which enabled biophysical analysis using whole-cell patch clamp recording in a mammalian cell line, HEK 293 cells, and two-electrode voltage clamp electrophysiology in Xenopus oocytes. The results suggest that the E protein forms an ion channel that is permeable to monovalent cations such as Na+ , Cs+ and K+ . The E current is nearly time- and voltage-independent when E protein is expressed in mammalian cells, and is modulated by changes of pH. At pH 6.0 and 7.4, the E protein current is activated, whereas at pH 8.0 and 9.0, the amplitude of E protein current is reduced, and in oocytes the inward E current fades at pH 9 in a time- and voltage-dependent manner. Using this directed targeting method and electrophysiological recordings, potential inhibitors of the E protein can be screened and subsequently investigated for antiviral activity against SARS-CoV-2 in vitro and possible efficacy in treating COVID-19.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , Cationes , Células HEK293 , Humanos , Concentración de Iones de Hidrógeno
15.
Rheumatology (Oxford) ; 60(12): 5843-5853, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33605409

RESUMEN

OBJECTIVE: Cartilage and bone damage in RA are associated with elevated IL-1ß. The effects of IL-1ß can be reduced by biological therapies that target IL-1ß or TNF-α. However, the mechanisms responsible for increased IL-1ß and the effect of anti-TNF-α have not been fully elucidated. Recently, sterile-α and armadillo motif containing protein (SARM) was identified as a negative regulator of toll-like receptor (TLR) induced IL-1ß secretion through an interaction with the inflammasome. This study set out to investigate SARM during TLR-induced IL-1ß secretion in RA peripheral blood monocytes and in patients commencing anti-TNF-α treatment. METHODS: Monocytes were isolated from RA patients and healthy controls; disease activity was measured by DAS28. IL-1ß secretion was measured by ELISA following TLR1/2, TLR4 and TLR7/8 stimulation. The mRNA expression of SARM1, IL-1ß and the components of the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome were measured by quantitative PCR. SARM protein expression was measured by western blotting. RESULTS: TLR1/2 activation induced elevated IL-1ß in RA monocytes compared with healthy controls (P = 0.0009), which negatively correlated with SARM1 expression (P = 0.0086). Lower SARM expression also correlated with higher disease activity (P = 0.0246). Additionally, patients responding to anti-TNF-α treatment demonstrated a rapid upregulation of SARM, which was not observed in non-responders. CONCLUSION: Together, these data highlight a potential contribution from SARM to RA pathophysiology where decreased SARM may lead to elevated IL-1ß associated with RA pathogenesis. Furthermore, the data additionally present a potential mechanism by which TNF-α blockade can modify IL-1ß secretion.


Asunto(s)
Proteínas del Dominio Armadillo/genética , Artritis Reumatoide/genética , Proteínas del Citoesqueleto/genética , Regulación de la Expresión Génica , Inflamasomas/genética , Interleucina-1beta/genética , ARN/genética , Receptor Toll-Like 2/genética , Adulto , Proteínas del Dominio Armadillo/biosíntesis , Artritis Reumatoide/sangre , Artritis Reumatoide/diagnóstico , Proteínas del Citoesqueleto/biosíntesis , Femenino , Humanos , Inflamasomas/metabolismo , Interleucina-1beta/biosíntesis , Masculino , Receptor Toll-Like 2/biosíntesis
16.
Brain Behav Immun ; 98: 299-309, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34450247

RESUMEN

OBJECTIVE: There is increasing evidence for a subgroup of major depressive disorder (MDD) associated with heightened peripheral blood inflammatory markers. In this study, we aimed to understand the mechanistic brain-immune axis in inflammation-linked depression by investigating associations between functional connectivity (FC) of brain networks and peripheral blood immune markers in depression. METHODS: Resting-state functional magnetic resonance imaging (fMRI) and peripheral blood inflammatory markers (C-reactive protein; CRP, interleukin-6; IL-6 and immune cells) were collected on N = 46 healthy controls (HC; CRP ≤ 3 mg/L) and N = 83 cases of depression, stratified further into low CRP cases (loCRP cases; ≤ 3 mg/L; N = 50) and high CRP cases (hiCRP cases; > 3 mg/L; N = 33). In a two-part analysis, network-based statistics (NBS) was firstly used to ascertain whole-brain FC differences in HC vs hiCRP cases. Secondly, we investigated the association between this network of interconnected brain regions and continuous measures of peripheral CRP (N = 83), IL-6 (N = 72), neutrophils and CD4+ T-cells (N = 36) in depression cases only. RESULTS: Case-control NBS testing revealed a single network of abnormally attenuated FC in the high CRP depression cases compared to healthy controls. Connections within this network were mainly between brain regions located in the left insula/frontal operculum and posterior cingulate cortex, which were assigned to ventral attention and default mode canonical fMRI networks respectively. Within-group analysis across all depression cases, secondarily demonstrated that FC within the identified network significantly negatively scaled with CRP, IL-6 and neutrophils. CONCLUSIONS: The findings suggest that inflammation is associated with disruption of functional connectivity within a brain network deemed critical for interoceptive signalling, e.g. accurate communication of peripheral bodily signals such as immune states to the brain, with implications for the pathogenesis of inflammation-linked depression.


Asunto(s)
Trastorno Depresivo Mayor , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Depresión , Trastorno Depresivo Mayor/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética
17.
J Child Psychol Psychiatry ; 62(10): 1202-1219, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33748971

RESUMEN

OBJECTIVE: Some studies have suggested alterations of structural brain asymmetry in attention-deficit/hyperactivity disorder (ADHD), but findings have been contradictory and based on small samples. Here, we performed the largest ever analysis of brain left-right asymmetry in ADHD, using 39 datasets of the ENIGMA consortium. METHODS: We analyzed asymmetry of subcortical and cerebral cortical structures in up to 1,933 people with ADHD and 1,829 unaffected controls. Asymmetry Indexes (AIs) were calculated per participant for each bilaterally paired measure, and linear mixed effects modeling was applied separately in children, adolescents, adults, and the total sample, to test exhaustively for potential associations of ADHD with structural brain asymmetries. RESULTS: There was no evidence for altered caudate nucleus asymmetry in ADHD, in contrast to prior literature. In children, there was less rightward asymmetry of the total hemispheric surface area compared to controls (t = 2.1, p = .04). Lower rightward asymmetry of medial orbitofrontal cortex surface area in ADHD (t = 2.7, p = .01) was similar to a recent finding for autism spectrum disorder. There were also some differences in cortical thickness asymmetry across age groups. In adults with ADHD, globus pallidus asymmetry was altered compared to those without ADHD. However, all effects were small (Cohen's d from -0.18 to 0.18) and would not survive study-wide correction for multiple testing. CONCLUSION: Prior studies of altered structural brain asymmetry in ADHD were likely underpowered to detect the small effects reported here. Altered structural asymmetry is unlikely to provide a useful biomarker for ADHD, but may provide neurobiological insights into the trait.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Trastorno del Espectro Autista , Adolescente , Adulto , Encéfalo/diagnóstico por imagen , Núcleo Caudado , Niño , Humanos , Imagen por Resonancia Magnética
18.
J Vasc Interv Radiol ; 32(7): 1011-1015.e1, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33831561

RESUMEN

PURPOSE: To evaluate the utility of computed tomography (CT) angiography before transarterial embolization (TAE) in predicting TAE's technical success for type II endoleaks (T2ELs). MATERIALS AND METHODS: Fifty-eight patients (mean age, 74.4 years; range, 46-89 years) who underwent attempted TAE for T2EL from July 2014 to August 2019 and underwent CT angiography before the procedure were included. Each CT angiography result was assessed for a feeding artery that was traceable over its entire course from either the superior mesenteric artery or the internal iliac artery to the endoleak cavity. TAE was performed using coils and was considered technically successful if embolization of the endoleak cavity and feeding artery was performed. The technical success rates were compared between patients with and without traceable feeding arteries. RESULTS: A fully traceable feeding artery supplying 75% (44/59) of endoleaks in the cohort was identified. TAE was technically successful in 95% (42/44) of these cases but only in 13% (2/15) of the cases without a fully traceable feeding artery (P < .001). When the inferior mesenteric artery was the feeding artery, it was always fully traceable, and TAE was technically successful in 100% (33/33) of the cases. When a lumbar artery was the feeding artery, it was fully traceable in only 42% (11/26) of the cases. When the lumbar artery was not fully traceable, TAE was technically successful in only 13% (2/15) of the cases. CONCLUSIONS: The traceability of a feeding artery over its entire course to an endoleak cavity using CT angiography was associated with TAE's technical success. Lumbar feeding arteries were less likely to be fully traceable. TAE's high failure rate when the feeding artery was not fully traceable suggests that translumbar embolization can be considered as an initial approach for theses patients.


Asunto(s)
Aneurisma de la Aorta Abdominal , Implantación de Prótesis Vascular , Embolización Terapéutica , Procedimientos Endovasculares , Anciano , Angiografía , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/cirugía , Angiografía por Tomografía Computarizada , Embolización Terapéutica/efectos adversos , Endofuga/diagnóstico por imagen , Endofuga/etiología , Endofuga/terapia , Procedimientos Endovasculares/efectos adversos , Humanos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
20.
Brain Behav Immun ; 87: 229-237, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31794798

RESUMEN

Childhood trauma is among the most potent contributing risk factors for depression and is associated with poor treatment response. Hypothalamic-pituitary-adrenal (HPA) axis abnormalities have been linked to both childhood trauma and depression, but the underlying mechanisms are poorly understood. The present study aimed to investigate the link between childhood trauma, HPA axis activity and antidepressant response in patients with depression. As part of the Wellcome Trust NIMA consortium, 163 depressed patients and 55 healthy volunteers were included in this study. Adult patients meeting Structured Clinical Interview for Diagnostic and Statistical Manual Version-5 criteria for major depression were categorised into subgroups of treatment responder (n = 42), treatment non-responder (n = 80) and untreated depressed (n = 41) based on current depressive symptom severity measured by the 17-item Hamilton Rating Scale for Depression and exposure to antidepressant medications established by Antidepressant Treatment Response Questionnaire. Childhood Trauma Questionnaire was obtained. Baseline serum C-reactive protein was measured using turbidimetric detection. Salivary cortisol was analyzed at multiple time points during the day using the ELISA technique. Glucocorticoid resistance was defined as the coexistence of hypercortisolemia and inflammation. Our results show that treatment non-responder patients had higher exposure to childhood trauma than responders. No specific HPA axis abnormalities were found in treatment non-responder depressed patients. Untreated depressed showed increased diurnal cortisol levels compared with patients on antidepressant medication, and higher prevalence of glucocorticoid resistance than medicated patients and controls. The severity of childhood trauma was associated with increased diurnal cortisol levels only in individuals with glucocorticoid resistance. Therefore, our findings suggest that the severity of childhood trauma experience contributes to a lack of response to antidepressant treatment. The effects of childhood trauma on increased cortisol levels are specifically evident in patients with glucocorticoid resistance and suggest glucocorticoid resistance as a target for the development of personalized treatment for a subgroup of depressed patients with a history of childhood trauma rather than for all patients with resistance to antidepressant treatment.


Asunto(s)
Depresión , Sistema Hipotálamo-Hipofisario , Adulto , Antidepresivos/uso terapéutico , Niño , Depresión/tratamiento farmacológico , Humanos , Hidrocortisona , Sistema Hipófiso-Suprarrenal
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