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CORONAVIRUS COVID-19 Global Cases by the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University (JHU) ...

domingo, 31 de marzo de 2019

Un exceso de televisión favorece el declive cognitivo

Television viewing and cognitive decline in older age: findings from the English Longitudinal Study of Ageing

Abstract

There has been significant interest in the effects of television on cognition in children, but much less research has been carried out into the effects in older adults. This study aimed to explore whether television viewing behaviours in adults aged 50 or over are associated with a decline in cognition. Using data from the English Longitudinal Study of Aging involving 3,662 adults aged 50+, we used multivariate linear regression models to explore longitudinal associations between baseline television watching (2008/2009) and cognition 6 years later (2014/2015) while controlling for demographic factors, socio-economic status, depression, physical health, health behaviours and a range of other sedentary behaviours. Watching television for more than 3.5 hours per day is associated with a dose-response decline in verbal memory over the following six years, independent of confounding variables. These results are found in particular amongst those with better cognition at baseline and are robust to a range of sensitivity analyses exploring reverse causality, differential non-response and stability of television viewing. Watching television is not longitudinally associated with changes in semantic fluency. Overall our results provide preliminary data to suggest that television viewing for more than 3.5 hours per day is related to cognitive decline.

Una alteración genética, asociada a epilepsias farmacorresistentes

Identification of a somatic mutation in the RHEB gene through high depth and ultra-high depth next generation sequencing in a patient with Hemimegalencephaly and drug resistant Epilepsy

Abstract

Malformations of cortical development are a frequent cause of drug-resistant Epilepsy and developmental delay. Hemimegalencephaly is a Malformation of cortical development characterized by enlargement of all or a part of one cerebral hemisphere. Germline and somatic mutation in genes belonging to the Mammalian Target of Rapamycin (mTOR) pathway has been identified in patients suffering from epilepsy secondary to Hemimegalencephaly and focal cortical dysplasia. We present here a patient suffering from severe neonatal Epilepsy since 3 h of life secondary to Hemimegalencephaly, requiring an anatomic hemispherectomy surgical procedure for seizure control, where by means of next-generation sequencing at an ultra-high depth coverage, we were able to identify a novel somatic mutation in the RHEB gene (NM_005614: c.119A > T: p. Glu40Val). The histopathological diagnosis was Cortical Dysplasia type IIB determined by the presence of dysmorphic neurons of variable size with nuclear alteration and balloon cells in the context of Hemimegalencephaly, which are similar to that have been demonstrated in hyperactivating RHEB models. This is the first report of a somatic mutation in RHEB gene in a patient suffering from Epilepsy secondary to Hemimegalencephaly. It highlights different current topics in the fields of genetics of Malformations of cortical development: a-somatic mosaicism is not uncommon in these neurodevelopmental disorders; b-the molecular diagnostic approach should involve the use of state-of-the-art methods and the sampling of different tissues; c-new findings might facilitate therapeutics discoveries while providing an improved understanding of normal brain development.

Keywords

Somatic mutation
RHEB gene
Hemimegalencephaly
Drug resistant Epilepsy

Un gen implicado en el TDAH podría relacionarse con el consumo de sustancias adictivas

ADGRL3 (LPHN3) variants predict substance use disorder

Abstract

Genetic factors are strongly implicated in the susceptibility to develop externalizing syndromes such as attention-deficit/hyperactivity disorder (ADHD), oppositional defiant disorder, conduct disorder, and substance use disorder (SUD). Variants in the ADGRL3 (LPHN3) gene predispose to ADHD and predict ADHD severity, disruptive behaviors comorbidity, long-term outcome, and response to treatment. In this study, we investigated whether variants within ADGRL3 are associated with SUD, a disorder that is frequently co-morbid with ADHD. Using family-based, case-control, and longitudinal samples from disparate regions of the world (n = 2698), recruited either for clinical, genetic epidemiological or pharmacogenomic studies of ADHD, we assembled recursive-partitioning frameworks (classification tree analyses) with clinical, demographic, and ADGRL3 genetic information to predict SUD susceptibility. Our results indicate that SUD can be efficiently and robustly predicted in ADHD participants. The genetic models used remained highly efficient in predicting SUD in a large sample of individuals with severe SUD from a psychiatric institution that were not ascertained on the basis of ADHD diagnosis, thus identifying ADGRL3 as a risk gene for SUD. Recursive-partitioning analyses revealed that rs4860437 was the predominant predictive variant. This new methodological approach offers novel insights into higher order predictive interactions and offers a unique opportunity for translational application in the clinical assessment of patients at high risk for SUD.

La liberación de BDNF mejora déficits de memoria en un modelo animal de enfermedad de Alzheimer

Conditional BDNF Delivery from Astrocytes Rescues Memory Deficits, Spine Density, and Synaptic Properties in the 5xFAD Mouse Model of Alzheimer Disease

Abstract

It has been well documented that neurotrophins, including brain-derived neurotrophic factor (BDNF), are severely affected in Alzheimer's disease (AD), but their administration faces a myriad of technical challenges. Here we took advantage of the early astrogliosis observed in an amyloid mouse model of AD (5xFAD) and used it as an internal sensor to administer BDNF conditionally and locally. We first demonstrate the relevance of BDNF release from astrocytes by evaluating the effects of coculturing WT neurons and BDNF-deficient astrocytes. Next, we crossed 5xFAD mice with pGFAP:BDNF mice (only males were used) to create 5xFAD mice that overexpress BDNF when and where astrogliosis is initiated (5xF:pGB mice). We evaluated the behavioral phenotype of these mice. We first found that BDNF from astrocytes is crucial for dendrite outgrowth and spine number in cultured WT neurons. Double-mutant 5xF:pGB mice displayed improvements in cognitive tasks compared with 5xFAD littermates. In these mice, there was a rescue of BDNF/TrkB downstream signaling activity associated with an improvement of dendritic spine density and morphology. Clusters of synaptic markers, PSD-95 and synaptophysin, were also recovered in 5xF:pGB compared with 5xFAD mice as well as the number of presynaptic vesicles at excitatory synapses. Additionally, experimentally evoked LTP in vivo was increased in 5xF:pGB mice. The beneficial effects of conditional BDNF production and local delivery at the location of active neuropathology highlight the potential to use endogenous biomarkers with early onset, such as astrogliosis, as regulators of neurotrophic therapy in AD.
SIGNIFICANCE STATEMENT Recent evidence places astrocytes as pivotal players during synaptic plasticity and memory processes. In the present work, we first provide evidence that astrocytes are essential for neuronal morphology via BDNF release. We then crossed transgenic mice (5xFAD mice) with the transgenic pGFAP-BDNF mice, which express BDNF under the GFAP promoter. The resultant double-mutant mice 5xF:pGB mice displayed a full rescue of hippocampal BDNF loss and related signaling compared with 5xFAD mice and a significant and specific improvement in all the evaluated cognitive tasks. These improvements did not correlate with amelioration of β amyloid load or hippocampal adult neurogenesis rate but were accompanied by a dramatic recovery of structural and functional synaptic plasticity.

sábado, 23 de marzo de 2019

El trastorno obsesivo compulsivo se debería a un bucle de errores del cerebro

Error Processing and Inhibitory Control in Obsessive-Compulsive Disorder: A Meta-analysis Using Statistical Parametric Maps

Abstract


Error processing and inhibitory control enable the adjustment of behaviors to meet task demands. Functional magnetic resonance imaging studies report brain activation abnormalities in patients with obsessive-compulsive disorder (OCD) during both processes. However, conclusions are limited by inconsistencies in the literature and small sample sizes. Therefore, the aim here was to perform a meta-analysis of the existing literature using unthresholded statistical maps from previous studies.

Methods

A voxelwise seed-based d mapping meta-analysis was performed using t-maps from studies comparing patients with OCD and healthy control subjects (HCs) during error processing and inhibitory control. For the error processing analysis, 239 patients with OCD (120 male; 79 medicated) and 229 HCs (129 male) were included, while the inhibitory control analysis included 245 patients with OCD (120 male; 91 medicated) and 239 HCs (135 male).

Results

Patients with OCD, relative to HCs, showed longer inhibitory control reaction time (standardized mean difference = 0.20, p = .03, 95% confidence interval = 0.016, 0.393) and more inhibitory control errors (standardized mean difference = 0.22, p = .02, 95% confidence interval = 0.039, 0.399). In the brain, patients showed hyperactivation in the bilateral dorsal anterior cingulate cortex, supplementary motor area, and pre-supplementary motor area as well as right anterior insula/frontal operculum and anterior lateral prefrontal cortex during error processing but showed hypoactivation during inhibitory control in the rostral and ventral anterior cingulate cortices and bilateral thalamus/caudate, as well as the right anterior insula/frontal operculum, supramarginal gyrus, and medial orbitofrontal cortex (all seed-based d mapping z value >2, p < .001).

Conclusions

A hyperactive error processing mechanism in conjunction with impairments in implementing inhibitory control may underlie deficits in stopping unwanted compulsive behaviors in the disorder.

El eje microbiota-intestino-cerebro y sus grandes proyecciones

The microbiota-gut-brain axis and its great projections

Introducción. Se denomina microbiota al conjunto de millones de microorganismos que conviven de manera simbiótica en nuestro organismo. Este conjunto bacteriano, que se localiza principalmente en el tracto digestivo, se distribuye a lo largo de los diferentes órganos en función de las propiedades químicas. Los factores que influyen en su composición son múltiples (dieta, hábitos individuales, fármacos). La microbiota colabora en varias funciones, como pueden ser el metabolismo o la inmunidad. 

Desarrollo. En los últimos años se ha puesto de relieve el papel bidireccional de la microbiota del tracto digestivo y del sistema nervioso central, es el denominado eje intestino-cerebro. En lo que a este eje se refiere, se cree que la ‘comunicación’ se produce a través de tres vías: el nervio vago, la vía sistémica (mediante la liberación de hormonas, metabolitos y neurotransmisores) y el sistema inmune (por la acción de las citocinas). 

Conclusiones. Aunque aún quedan muchas incógnitas por esclarecer, este eje se postula como una posible base patógena para numerosos trastornos neurológicos de gran impacto sanitario, como la enfermedad de Alzheimer, la enfermedad de Parkinson o la esclerosis múltiple. En el momento actual se están llevando a cabo estudios que intentan evaluar el impacto de los probióticos sobre algunas de estas enfermedades neurológicas.

Eje intestino-cerebroEnfermedad de AlzheimerEnfermedad de ParkinsonEpilepsiaEsclerosis múltipleMicrobiota






Un estudio muestra que la dasotralina sería eficaz para tratar el TDAH

Dasotraline in Children with Attention-Deficit/Hyperactivity Disorder: A Six-Week, Placebo-Controlled, Fixed-Dose Trial

Abstract

Objective: Dasotraline is a potent inhibitor of presynaptic dopamine and norepinephrine reuptake with a pharmacokinetic profile characterized by slow absorption and a long elimination half-life. The aim of this study was to evaluate the efficacy and safety of dasotraline in children with attention-deficit/hyperactivity disorder (ADHD).
Methods: Children aged 6–12 years with a Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) diagnosis of ADHD were randomized to 6 weeks of double-blind once-daily treatment with dasotraline (2 or 4 mg) or placebo. The primary efficacy endpoint was change from baseline in the ADHD Rating Scale Version IV–Home Version (ADHD RS-IV HV) total score at week 6.
Results: A total of 342 patients were randomized to dasotraline or placebo (mean age 9.1 years, 66.7% male). Treatment with dasotraline was associated with significant improvement at study endpoint in the ADHD RS-IV HV total score for the 4 mg/day dose versus placebo (−17.5 vs. −11.4; p < 0.001; effect size [ES], 0.48), but not for the 2 mg/day dose (−11.8 vs. −11.4; ns; ES, 0.03). A regression analysis confirmed a significant linear dose–response relationship for dasotraline. Significant improvement for dasotraline 4 mg/day dose versus placebo was also observed across the majority of secondary efficacy endpoints, including the Clinical Global Impression (CGI)–Severity score, the Conners Parent Rating Scale-Revised scale (CPRS-R) ADHD index score, and subscale measures of hyperactivity and inattentiveness. Discontinuation rates due to adverse events (AEs) were higher in the dasotraline 4 mg/day group (12.2%) compared with the 2 mg/day group (6.3%) and placebo (1.7%). The most frequent AEs associated with dasotraline were insomnia, decreased appetite, decreased weight, and irritability. Psychosis-related symptoms were reported as AEs by 7/219 patients treated with dasotraline in this study. There were no serious AEs or clinically meaningful changes in blood pressure or heart rate on dasotraline.
Conclusion: In this placebo-controlled study, treatment with dasotraline 4 mg/day significantly improved ADHD symptoms and behaviors, including attention and hyperactivity, in children aged 6–12 years. The most frequently reported AEs observed on dasotraline included insomnia, decreased appetite, decreased weight, and irritability.

Una mutación genética, causa de una nueva miopatía congénita

Recessive mutations in muscle-specific isoforms of FXR1 cause congenital multi-minicore myopathy

Abstract

FXR1 is an alternatively spliced gene that encodes RNA binding proteins (FXR1P) involved in muscle development. In contrast to other tissues, cardiac and skeletal muscle express two FXR1P isoforms that incorporate an additional exon-15. We report that recessive mutations in this particular exon of FXR1 cause congenital multi-minicore myopathy in humans and mice. Additionally, we show that while Myf5-dependent depletion of all FXR1P isoforms is neonatal lethal, mice carrying mutations in exon-15 display non-lethal myopathies which vary in severity depending on the specific effect of each mutation on the protein.

Fig. 1



Fig. 1
Clinical features and mutations. a Pedigree of Family 1 showing the proband (arrow), similarly affected older female sibling and affected fetus. DNA-sequencing chromatograms demonstrate a homozygous four nucleotide deletion at the 3′-end of FXR1 exon-15 in the proband, which is in the heterozygous state in his mother (carrier). Carrier chromatogram shows normal (top) and mutant (underneath) nucleotide sequences. b Proband of family 1 at the age of 2.5 months with inserted Ryle tube for feeding, short neck, short hands and digits, lateral rotation of right upper and lower limbs and medial rotation of left upper and lower limbs due to severe hypotonia. The picture also shows bilateral low inserted thumbs with dorsi-flexion of both feet, no obvious demarcation of large joints with transverse crease on the left knee and ankles and genital hypoplasia. c X-rays (AP view) showing bilateral mid fractures of humeri (upper panel, arrow) and femora (lower panel, arrow). d Pedigree of family 2 and DNA-sequencing chromatograms corresponding to the 5′-end of FXR1 exon-15 of the mother (carrier) and one of the affected siblings showing a single adenine deletion from a run of eight-adenines in the homozygous state in the patient. The father was not available for carrier testing. Only nucleotide sequence of the wt allele is written on the chromatogram of the mother. e–h Representative photomicrographs of H-E staining. Scale bar 60 µm (e), Masson trichrome staining. Scale bar 500 µm (f), ATPase pH4.3 histochemistry. Scale bar 200 µm (g), and TEM. Scale bar 10 µm (h) from a right triceps biopsy of individual II-4 of family 2. Arrows indicate internalized nuclei, fatty infiltration, and areas of Z-streaming and minicores in e, f and h, respectively. Different fibers in TEM images are numbered

Voz y habla de los niños con síndrome de deleción de 22q11

Voice and speech of children with 22q11 deletion syndrome


INTRODUCTION:


The 22q11 deletion syndrome (S22q11) is a genetic disorder caused by the loss of a fragment of the chromosome 22. The clinical manifestations associated with the syndrome are diverse, including learning difficulties and alterations in voice, speech and language. However, to date we have not found any study that evaluates these aspects in the Spanish population with S22q11.

PATIENTS AND METHODS:


We evaluate the voice and speech of a sample of 10 boys and 7 girls, aged 3 years and 3 months to 13 years and 9 months old (mean age: 9,4 ± 3,5 years old) with S22q11, with voice recordings and a phonological and phonetic evaluation. Also, semistructured type interview is administered to parents.

RESULTS:


Most children of our series, both male and female, with S22q11 have a deeper voice than expected by gender and age, except for male children over 12 years. In terms of intensity, all of them are within the parameters of normality in spontaneous conversation. Almost all of them showed alterations in voice quality, mainly due to hypernasality. Regarding the speech, there are major difficulties in the articulation of fricatives, affricates and vibrant rhotic consonant clusters + /r/. Likewise, children, especially the youngest ones, make use of glottal stops to replace consonants.

CONCLUSIONS:


In the studied sample, most of the children with S22q11 have specific voice and speech alterations.

El sistema endocannabinoide, posible diana para mejorar las alteraciones cognitivas en el síndrome de Down

Cannabinoid type-1 receptor blockade restores neurological phenotypes in two models for Down syndrome

Abstract

Intellectual disability is the most limiting hallmark of Down syndrome, for which there is no gold-standard clinical treatment yet. The endocannabinoid system is a widespread neuromodulatory system involved in multiple functions including learning and memory processes. Alterations of this system contribute to the pathogenesis of several neurological and neurodevelopmental disorders. However, the involvement of the endocannabinoid system in the pathogenesis of Down syndrome has not been explored before. We used the best-characterized preclinical model of Down syndrome, the segmentally trisomic Ts65Dn model. In male Ts65Dn mice, cannabinoid type-1 receptor (CB1R) expression was enhanced and its function increased in hippocampal excitatory terminals. Knockdown of CB1R in the hippocampus of male Ts65Dn mice restored hippocampal-dependent memory. Concomitant with this result, pharmacological inhibition of CB1R restored memory deficits, hippocampal synaptic plasticity and adult neurogenesis in the subgranular zone of the dentate gyrus. Notably, the blockade of CB1R also normalized hippocampal-dependent memory in female Ts65Dn mice. To further investigate the mechanisms involved, we used a second transgenic mouse model overexpressing a single gene candidate for Down syndrome cognitive phenotypes, the dual specificity tyrosine-phosphorylation-regulated kinase 1A (DYRK1A). CB1R pharmacological blockade similarly improved cognitive performance, synaptic plasticity and neurogenesis in transgenic male Dyrk1A mice. Our results identify CB1R as a novel druggable target potentially relevant for the improvement of cognitive deficits associated with Down syndrome.

    Ciertas características de la personalidad afectan a la intensidad del dolor neuropático crónico

    Influence of behavioral traits in the inter-individual variability of nociceptive, emotional and cognitive manifestations of neuropathic pain

    Abstract

    Neuropathic pain is a complex disorder associated with emotional and cognitive deficits that may impair nociceptive manifestations. There is high inter-individual variability in the manifestations of human neuropathic pain, which largely depends on personality traits. We aim to identify the influence of different behavioral traits in the inter-individual vulnerability to neuropathic pain manifestations using behavioral, electrophysiological and genetic approaches. We first selected mice with extreme social and emotional traits and look for correlation with the spontaneous neuronal activity in the central amygdala. Neuropathic pain was induced to these mice to evaluate the influence of behavioral traits on nociceptive manifestations and gene expression profiles in the amygdala. Our results show an association of the spontaneous central amygdala neuronal activity with the sociability behavior. We demonstrate that low sociable, high anxious and low depressive phenotypes develop enhanced nociceptive hypersensitivity after nerve injury. However, greater emotional alterations and cognitive impairment are observed in high sociable, anxious-like and depressive-like mice, indicating that nociceptive, emotional and cognitive manifestations of neuropathic pain do not correlate with each other. Gene analyses identify high Pdyn and Il6levels in the amygdala as indicative of enhanced nociceptive hypersensitivity and reveal an association between high Gadd45 expression and attenuated emotional and cognitive manifestations of neuropathic pain.

    domingo, 17 de marzo de 2019

    Problemas del sueño en niños con autismo

    Sleep Problems in 2- to 5-Year-Olds With Autism Spectrum Disorder and Other Developmental Delays

    BACKGROUND: Sleep problems can impact daytime behavior, quality of life, and overall health. We compared sleep habits in young children with autism spectrum disorder (ASD) and other developmental delays and disorders and in children from the general population (POP).
    METHODS: We included 2- to 5-year-old children whose parent completed all items on the Children’s Sleep Habits Questionnaire (CSHQ) in a multisite case-control study: 522 children with ASD; 228 children with other developmental delays and disorders with autism spectrum disorder characteristics (DD w/ASD); 534 children with other developmental delays and disorders without autism spectrum disorder characteristics (DD w/o ASD); and 703 POP. Multivariable analysis of variance compared CSHQ mean total score (TS) and subscale scores between groups. Logistic regression analysis examined group differences by using TS cutoffs of 41 and 48. Analyses were adjusted for covariates.
    RESULTS: Mean CSHQ TS for children in each group: ASD (48.5); DD w/ASD (50.4); DD w/o ASD (44.4); and POP (43.3). Differences between children with ASD and both children with DD w/o ASD and POP were statistically significant. Using a TS cutoff of 48, the proportion of children with sleep problems was significantly higher in children in the ASD group versus DD w/o ASD and POP groups (adjusted odds ratios [95% confidence intervals]: 2.12 [1.57 to 2.87] and 2.37 [1.75 to 3.22], respectively).
    CONCLUSIONS: Sleep problems are more than twice as common in young children with ASD and DD w/ASD. Screening for sleep problems is important in young children to facilitate provision of appropriate interventions.


    Video Abstract

    Los oyentes se hacen una idea de la personalidad del hablante a través de su voz, con independencia del idioma

    Forming social impressions from voices in native and foreignlanguages

    Abstract 

    We form very rapid personality impressions about speakers on hearing a single word. This implies that the acoustical properties of the voice (e.g., pitch) are very powerful cues when forming social impressions. Here, we aimed to explore how personality impressions for brief social utterances transfer across languages and whether acoustical properties play a similar role in driving personality impressions. Additionally, we examined whether evaluations are similar in the native and a foreign language of the listener. In two experiments we asked Spanish listeners to evaluate personality traits from different instances of the Spanish word “Hola” (Experiment 1) and the English word “Hello” (Experiment 2), native and foreign language respectively. The results revealed that listeners across languages form very similar personality impressions irrespective of whether the voices belong to the native or the foreign language of the listener. A social voice space was summarized by two main personality traits, one emphasizing valence (e.g., trust) and the other strength (e.g., dominance). Conversely, the acoustical properties that listeners pay attention to when judging other’s personality vary across languages. These results provide evidence that social voice perception contains certain elements invariant across cultures/languages, while others are modulated by the cultural/linguistic background of the listener.


    Biomarcador y algoritmo para detectar la fase inicial de la enfermedad de Parkinson

    Longitudinal Connectomes as a Candidate Progression Marker for Prodromal Parkinson’s Disease

    Abstract 
    Parkinson’s disease is the second most prevalent neurodegenerative disorder in the Western world. It is estimated that the neuronal loss related to Parkinson’s disease precedes the clinical diagnosis by more than 10 years (prodromal phase) which leads to a subtle decline that translates into non-specific clinical signs and symptoms. By leveraging diffusion magnetic resonance imaging brain (MRI) data evaluated longitudinally, at least at two different time points, we have the opportunity of detecting and measuring brain changes early on in the neurodegenerative process, thereby allowing early detection and monitoring that can enable development and testing of disease modifying therapies. In this study, we were able to define a longitudinal degenerative Parkinson’s disease progression pattern using diffusion magnetic resonance imaging connectivity information. Such pattern was discovered using a de novo early Parkinson’s disease cohort (n = 21), and a cohort of Controls (n = 30). Afterward, it was tested in a cohort at high risk of being in the Parkinson’s disease prodromal phase (n = 16). This progression pattern was numerically quantified with a longitudinal brain connectome progression score. This score is generated by an interpretable machine learning (ML) algorithm trained, with cross-validation, on the longitudinal connectivity information of Parkinson’s disease and Control groups computed on a nigrostriatal pathway-specific parcellation atlas. Experiments indicated that the longitudinal brain connectome progression score was able to discriminate between the progression of Parkinson’s disease and Control groups with an area under the receiver operating curve of 0.89 [confidence interval (CI): 0.81–0.96] and discriminate the progression of the High Risk Prodromal and Control groups with an area under the curve of 0.76 [CI: 0.66–0.92]. In these same subjects, common motor and cognitive clinical scores used in Parkinson’s disease research showed little or no discriminative ability when evaluated longitudinally. Results suggest that it is possible to quantify neurodegenerative patterns of progression in the prodromal phase with longitudinal diffusion magnetic resonance imaging connectivity data and use these image-based patterns as progression markers for neurodegeneration.
    Keywords: longitudinal connectomes, machine learning, neurodegeneration, prodromal Parkinson’s disease, diffusion magnetic resonance imaging

    Un reloj biológico coordina la defensa inmune y la protección vascular

    A Neutrophil Timer Coordinates Immune Defense and VascularProtection

    Abstract 

    Neutrophils eliminate pathogens efficiently but can inflict severe damage to the host if they over-activate within blood vessels. It is unclear how immunity solves the dilemma of mounting an efficient anti-microbial defense while preserving vascular health. Here, we identify a neutrophil-intrinsic program that enabled both. The gene Bmal1 regulated expression of the chemokine CXCL2 to induce chemokine receptor CXCR2-dependent diurnal changes in the transcriptional and migratory properties of circulating neutrophils. These diurnal alterations, referred to as neutrophil aging, were antagonized by CXCR4 (C-X-C chemokine receptor type 4) and regulated the outer topology of neutrophils to favor homeostatic egress from blood vessels at night, resulting in boosted anti-microbial activity in tissues. Mice engineered for constitutive neutrophil aging became resistant to infection, but the persistence of intravascular aged neutrophils predisposed them to thrombo-inflammation and death. Thus, diurnal compartmentalization of neutrophils, driven by an internal timer, coordinates immune defense and vascular protection.

    Graphical Abstract
    Figure thumbnail fx1

    Nuevo biosensor ultrasensible para la detección precoz del lupus eritematoso sistémico

      Abstract
      The mechanism of self-recognition of the autoantigen TROVE2, a common biomarker in autoimmune diseases, has been studied with a quartz crystal microbalance with dissipation monitoring (QCM-D) and dual polarization interferometry (DPI). The complementarity and remarkable analytical features of both techniques has allowed new insights into the onset of systemic lupus erythematosus (SLE) to be achieved at the molecular level. The in vitro study for SLE patients and healthy subjects suggests that anti-TROVE2 autoantibodies may undergo an antibody bipolar bridging. An epitope-paratope-specific binding initially occurs to activate a hidden Fc receptor in the TROVE2 tertiary structure. This bipolar mechanism may contribute to the pathogenic accumulation of anti-TROVE2 autoantibody immune complex in autoimmune disease. Furthermore, the specific calcium-dependent protein-protein bridges point out at how the TRIM21/TROVE2 association might occur, suggesting that the TROVE2 protein could stimulate the intracellular immune signaling via the TRIM21 PRY-SPRY domain. These findings may help to better understand the origins of the specificity and affinity of TROVE2 interactions, which might play a key role in the SLE pathogenesis. This manuscript gives one of the first practical applications of two novel functions (−df/dD and Δh/molec) for the analysis of the data provided by QCM-D and DPI. In addition, it is the first time that QCM-D has been used for mapping hidden Fc receptors as well as linear epitopes in a protein tertiary structure.

    sábado, 9 de marzo de 2019

    La dopamina modula la experiencia de recompensa provocada por la música

    Dopamine modulates the reward experiences elicited by music

    Abstract

    Understanding how the brain translates a structured sequence of sounds, such as music, into a pleasant and rewarding experience is a fascinating question which may be crucial to better understand the processing of abstract rewards in humans. Previous neuroimaging findings point to a challenging role of the dopaminergic system in music-evoked pleasure. However, there is a lack of direct evidence showing that dopamine function is causally related to the pleasure we experience from music. We addressed this problem through a double blind within-subject pharmacological design in which we directly manipulated dopaminergic synaptic availability while healthy participants (n = 27) were engaged in music listening. We orally administrated to each participant a dopamine precursor (levodopa), a dopamine antagonist (risperidone), and a placebo (lactose) in three different sessions. We demonstrate that levodopa and risperidone led to opposite effects in measures of musical pleasure and motivation: while the dopamine precursor levodopa, compared with placebo, increased the hedonic experience and music-related motivational responses, risperidone led to a reduction of both. This study shows a causal role of dopamine in musical pleasure and indicates that dopaminergic transmission might play different or additive roles than the ones postulated in affective processing so far, particularly in abstract cognitive activities.

    La falta de sueño incrementa la experiencia de dolor

    The pain of sleep loss: A brain characterization in humans

    Abstract

    Sleep loss increases the experience of pain. However, the brain mechanisms underlying altered pain processing following sleep deprivation are unknown. Moreover, it remains unclear whether ecologically modest night-to-night changes in sleep, within an individual, confer consequential day-to-day changes in experienced pain. Here, we demonstrate that acute sleep-deprivation amplifies pain reactivity within human (male and female) primary somatosensory cortex yet blunts pain-reactivity in higher-order valuation and decision-making regions of the striatum and insula cortex. Consistent with this altered neural signature, we further show that sleep deprivation expands the temperature range for classifying a stimulus as painful, specifically through a lowering of pain thresholds. Moreover, the degree of amplified reactivity within somatosensory cortex following sleep deprivation significantly predicts this expansion of experienced pain across individuals. Finally, outside of the laboratory setting, we similarly show that even modest nightly changes in sleep quality (increases and decreases) within an individual determine consequential day-to-day changes in experienced pain (decreases and increases, respectively). Together, these data provide a central brain framework underlying the impact of sleep loss on pain, and furthermore, establish that the association between sleep and pain is expressed in a night-to-day, bidirectional relationship within a sample of the general population. More broadly, our findings highlight sleep as a novel therapeutic target for pain management within and outside the clinic, including circumstances where sleep is frequently short yet pain is abundant (e.g. the hospital setting).

    Un control estricto de la presión arterial podría reducir el riesgo de deterioro cognitivo leve

    Effect of Intensive vs Standard Blood Pressure Control on Probable Dementia

    A Randomized Clinical Trial

    Abstract

    Importance  There are currently no proven treatments to reduce the risk of mild cognitive impairment and dementia.

    Objective.

    To evaluate the effect of intensive blood pressure control on risk of dementia.

    Design, Setting, and Participants.

    Randomized clinical trial conducted at 102 sites in the United States and Puerto Rico among adults aged 50 years or older with hypertension but without diabetes or history of stroke. Randomization began on November 8, 2010. The trial was stopped early for benefit on its primary outcome (a composite of cardiovascular events) and all-cause mortality on August 20, 2015. The final date for follow-up of cognitive outcomes was July 22, 2018.

    Interventions. 

    Participants were randomized to a systolic blood pressure goal of either less than 120 mm Hg (intensive treatment group; n = 4678) or less than 140 mm Hg (standard treatment group; n = 4683).

    Main Outcomes and Measures.

    The primary cognitive outcome was occurrence of adjudicated probable dementia. Secondary cognitive outcomes included adjudicated mild cognitive impairment and a composite outcome of mild cognitive impairment or probable dementia.

    Results.

    Among 9361 randomized participants (mean age, 67.9 years; 3332 women [35.6%]), 8563 (91.5%) completed at least 1 follow-up cognitive assessment. The median intervention period was 3.34 years. During a total median follow-up of 5.11 years, adjudicated probable dementia occurred in 149 participants in the intensive treatment group vs 176 in the standard treatment group (7.2 vs 8.6 cases per 1000 person-years; hazard ratio [HR], 0.83; 95% CI, 0.67-1.04). Intensive BP control significantly reduced the risk of mild cognitive impairment (14.6 vs 18.3 cases per 1000 person-years; HR, 0.81; 95% CI, 0.69-0.95) and the combined rate of mild cognitive impairment or probable dementia (20.2 vs 24.1 cases per 1000 person-years; HR, 0.85; 95% CI, 0.74-0.97).

    Conclusions and Relevance.

    Among ambulatory adults with hypertension, treating to a systolic blood pressure goal of less than 120 mm Hg compared with a goal of less than 140 mm Hg did not result in a significant reduction in the risk of probable dementia. Because of early study termination and fewer than expected cases of dementia, the study may have been underpowered for this end point.