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1.
Proc Natl Acad Sci U S A ; 121(23): e2318641121, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38814872

RESUMEN

A balanced excitation-inhibition ratio (E/I ratio) is critical for healthy brain function. Normative development of cortex-wide E/I ratio remains unknown. Here, we noninvasively estimate a putative marker of whole-cortex E/I ratio by fitting a large-scale biophysically plausible circuit model to resting-state functional MRI (fMRI) data. We first confirm that our model generates realistic brain dynamics in the Human Connectome Project. Next, we show that the estimated E/I ratio marker is sensitive to the gamma-aminobutyric acid (GABA) agonist benzodiazepine alprazolam during fMRI. Alprazolam-induced E/I changes are spatially consistent with positron emission tomography measurement of benzodiazepine receptor density. We then investigate the relationship between the E/I ratio marker and neurodevelopment. We find that the E/I ratio marker declines heterogeneously across the cerebral cortex during youth, with the greatest reduction occurring in sensorimotor systems relative to association systems. Importantly, among children with the same chronological age, a lower E/I ratio marker (especially in the association cortex) is linked to better cognitive performance. This result is replicated across North American (8.2 to 23.0 y old) and Asian (7.2 to 7.9 y old) cohorts, suggesting that a more mature E/I ratio indexes improved cognition during normative development. Overall, our findings open the door to studying how disrupted E/I trajectories may lead to cognitive dysfunction in psychopathology that emerges during youth.


Asunto(s)
Corteza Cerebral , Cognición , Imagen por Resonancia Magnética , Humanos , Cognición/fisiología , Cognición/efectos de los fármacos , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/crecimiento & desarrollo , Corteza Cerebral/metabolismo , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/fisiología , Masculino , Imagen por Resonancia Magnética/métodos , Femenino , Adolescente , Niño , Conectoma/métodos , Alprazolam/farmacología , Receptores de GABA-A/metabolismo , Adulto Joven
2.
Psychol Med ; : 1-12, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38314509

RESUMEN

BACKGROUND: Screen time in infancy is linked to changes in social-emotional development but the pathway underlying this association remains unknown. We aim to provide mechanistic insights into this association using brain network topology and to examine the potential role of parent-child reading in mitigating the effects of screen time. METHODS: We examined the association of screen time on brain network topology using linear regression analysis and tested if the network topology mediated the association between screen time and later socio-emotional competence. Lastly, we tested if parent-child reading time was a moderator of the link between screen time and brain network topology. RESULTS: Infant screen time was significantly associated with the emotion processing-cognitive control network integration (p = 0.005). This network integration also significantly mediated the association between screen time and both measures of socio-emotional competence (BRIEF-2 Emotion Regulation Index, p = 0.04; SEARS total score, p = 0.04). Parent-child reading time significantly moderated the association between screen time and emotion processing-cognitive control network integration (ß = -0.640, p = 0.005). CONCLUSION: Our study identified emotion processing-cognitive control network integration as a plausible biological pathway linking screen time in infancy and later socio-emotional competence. We also provided novel evidence for the role of parent-child reading in moderating the association between screen time and topological brain restructuring in early childhood.

3.
Brain Behav Immun ; 119: 781-791, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38677627

RESUMEN

There are inter-individual differences in susceptibility to the influence of early life experiences for which the underlying neurobiological mechanisms are poorly understood. Microglia play a role in environmental surveillance and may influence individual susceptibility to environmental factors. As an index of neurodevelopment, we estimated individual slopes of mean white matter fractional anisotropy (WM-FA) across three time-points (age 4.5, 6.0, and 7.5 years) for 351 participants. Individual variation in microglia reactivity was derived from an expression-based polygenic score(ePGS) comprised of Single Nucleotide Polymorphisms (SNPs) functionally related to the expression of microglia-enriched genes.A higher ePGS denotes an increased genetic capacity for the expression of microglia-related genes, and thus may confer a greater capacity to respond to the early environment and to influence brain development. We hypothesized that this ePGS would associate with the WM-FA index of neurodevelopment and moderate the influence of early environmental factors.Our findings show sex dependency, where a significant association between WM-FA and microglia ePGS was only obtained for females.We then examined associations with perinatal factors known to decrease (optimal birth outcomes and familial conditions) or increase (systemic inflammation) the risk for later mental health problems.In females, individuals with high microglia ePGS showed a negative association between systemic inflammation and WM-FA and a positive association between more advantageous environmental conditions and WM-FA. The microglia ePGS in females thus accounted for variations in the influence of the quality of the early environment on WM-FA.Finally, WM-FA slopes mediated the association of microglia ePGS with interpersonal problems and social hostility in females. Our findings suggest the genetic capacity for microglia function as a potential factor underlying differential susceptibility to early life exposuresthrough influences on neurodevelopment.


Asunto(s)
Microglía , Polimorfismo de Nucleótido Simple , Sustancia Blanca , Humanos , Microglía/metabolismo , Femenino , Masculino , Niño , Preescolar , Encéfalo/crecimiento & desarrollo , Encéfalo/metabolismo , Factores Sexuales , Herencia Multifactorial
4.
Phys Chem Chem Phys ; 26(3): 2291-2303, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38165716

RESUMEN

In the present work, a theoretical design for the viability of bilayer C4N3 (bi-C4N3) as a promising host material for Li-Se battery was conducted utilizing first-principles calculations. The AA- and AB-stacking configurations of bilayer C4N3 can effectively inhibit the shuttling of high-order polyselenides through the synergistic effect of physical confinement and strong Li-N bonds. Compared to conventional electrolytes, the AA- and AB-stacking bilayer C4N3 demonstrate enhanced adsorption capabilities for the polyselenides. The anchored structures of Se8 or Li2Sen (n = 1, 2, 4, 6, 8) molecules within the bilayer C4N3 exhibit high electrical conductivities, which are beneficial for enhancing the electrochemical performance. The catalytic effects of AA- and AB-stacking bilayer C4N3 were investigated by the reduction of Se8 and the energy barrier associated with the decomposition of Li2Se. The AA- and AB-stacking bilayer C4N3 can significantly decrease the activation barrier and promote the decomposition of Li2Se. The mean square displacement (MSD) curves reveal the pronounceably sluggish Li-ions diffusions in polyselenides within the AA- and AB-stacking bilayer C4N3, which in turn demonstrates the notable prospects in mitigating the shuttle effect.

5.
Neuroimage ; 278: 120273, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37473977

RESUMEN

BACKGROUND: Metabolic syndrome score in children assesses the risk of developing cardiovascular disease in future. We aim to probe the role of the caudate in relation to the metabolic syndrome score. Furthermore, using both functional and structural neuroimaging, we aim to examine the interplay between functional and structural measures. METHODS: A longitudinal birth cohort study with functional and structural neuroimaging data obtained at 4.5, 6.0 and 7.5 years and metabolic syndrome scores at 8.0 years was used. Pearson correlation and linear regression was used to test for correlation fractional anisotropy (FA) and fractional amplitude of low frequency fluctuations (fALFF) of the caudate with metabolic syndrome scores. Mediation analysis was used to test if later brain measures mediated the relation between earlier brain measures and metabolic syndrome scores. Inhibitory control was also tested as a mediator of the relation between caudate brain measures and metabolic syndrome scores. RESULTS: FA at 4.5 years and fALFF at 7.5 years of the left caudate was significantly correlated with metabolic syndrome scores. Post-hoc mediation analysis showed that fALFF at 7.5 years fully mediated the relation between FA at 4.5 years and metabolic syndrome scores. Inhibitory control was significantly correlated with fALFF at 7.5 years, but did not mediate the relation between fALFF at 7.5 years and metabolic syndrome scores. CONCLUSIONS: We found that variations in caudate microstructure at 4.5 years predict later variation in functional activity at 7.5 years. This later variation in functional activity fully mediates the relation between microstructural changes in early childhood and metabolic syndrome scores at 8.0 years.


Asunto(s)
Imagen por Resonancia Magnética , Síndrome Metabólico , Preescolar , Niño , Humanos , Imagen por Resonancia Magnética/métodos , Estudios de Cohortes , Síndrome Metabólico/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Mapeo Encefálico/métodos
6.
Neuroimage ; 273: 120010, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36918136

RESUMEN

Resting-state fMRI is commonly used to derive brain parcellations, which are widely used for dimensionality reduction and interpreting human neuroscience studies. We previously developed a model that integrates local and global approaches for estimating areal-level cortical parcellations. The resulting local-global parcellations are often referred to as the Schaefer parcellations. However, the lack of homotopic correspondence between left and right Schaefer parcels has limited their use for brain lateralization studies. Here, we extend our previous model to derive homotopic areal-level parcellations. Using resting-fMRI and task-fMRI across diverse scanners, acquisition protocols, preprocessing and demographics, we show that the resulting homotopic parcellations are as homogeneous as the Schaefer parcellations, while being more homogeneous than five publicly available parcellations. Furthermore, weaker correlations between homotopic parcels are associated with greater lateralization in resting network organization, as well as lateralization in language and motor task activation. Finally, the homotopic parcellations agree with the boundaries of a number of cortical areas estimated from histology and visuotopic fMRI, while capturing sub-areal (e.g., somatotopic and visuotopic) features. Overall, these results suggest that the homotopic local-global parcellations represent neurobiologically meaningful subdivisions of the human cerebral cortex and will be a useful resource for future studies. Multi-resolution parcellations estimated from 1479 participants are publicly available (https://github.com/ThomasYeoLab/CBIG/tree/master/stable_projects/brain_parcellation/Yan2023_homotopic).


Asunto(s)
Mapeo Encefálico , Encéfalo , Humanos , Encéfalo/fisiología , Mapeo Encefálico/métodos , Imagen por Resonancia Magnética/métodos , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/fisiología , Descanso
7.
Neuropathol Appl Neurobiol ; 49(2): e12894, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36843390

RESUMEN

AIMS: Glioneuronal tumours (GNTs) are poorly distinguished by their histology and lack robust diagnostic indicators. Previously, we showed that common GNTs comprise two molecularly distinct groups, correlating poorly with histology. To refine diagnosis, we constructed a methylation-based model for GNT classification, subsequently evaluating standards for molecular stratification by methylation, histology and radiology. METHODS: We comprehensively analysed methylation, radiology and histology for 83 GNT samples: a training cohort of 49, previously classified into molecularly defined groups by genomic profiles, plus a validation cohort of 34. We identified histological and radiological correlates to molecular classification and constructed a methylation-based support vector machine (SVM) model for prediction. Subsequently, we contrasted methylation, radiological and histological classifications in validation GNTs. RESULTS: By methylation clustering, all training and 23/34 validation GNTs segregated into two groups, the remaining 11 clustering alongside control cortex. Histological review identified prominent astrocytic/oligodendrocyte-like components, dysplastic neurons and a specific glioneuronal element as discriminators between groups. However, these were present in only a subset of tumours. Radiological review identified location, margin definition, enhancement and T2 FLAIR-rim sign as discriminators. When validation GNTs were classified by SVM, 22/23 classified correctly, comparing favourably against histology and radiology that resolved 17/22 and 15/21, respectively, where data were available for comparison. CONCLUSIONS: Diagnostic criteria inadequately reflect glioneuronal tumour biology, leaving a proportion unresolvable. In the largest cohort of molecularly defined glioneuronal tumours, we develop molecular, histological and radiological approaches for biologically meaningful classification and demonstrate almost all cases are resolvable, emphasising the importance of an integrated diagnostic approach.


Asunto(s)
Neoplasias Encefálicas , Neoplasias del Sistema Nervioso Central , Neoplasias Neuroepiteliales , Radiología , Humanos , Neoplasias Encefálicas/patología , Metilación de ADN , Neoplasias Neuroepiteliales/genética , Neoplasias del Sistema Nervioso Central/genética
8.
J Child Psychol Psychiatry ; 64(3): 426-436, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36331294

RESUMEN

BACKGROUND: Experiences of early life adversity pose significant psychological and physical health risks to exposed individuals. Emerging evidence suggests that these health risks can be transmitted across generations; however, the mechanisms underlying the intergenerational impacts of maternal early-life trauma on child health remain unknown. METHODS: The current study used a prospective longitudinal design to determine the unique and joint contributions of maternal childhood trauma (neglect and abuse) and maternal prenatal and postnatal mental health (anxiety and depressive symptoms) (N = 541) to children's resting frontoamygdala functional connectivity at 6 years (N = 89) and emotional health at 7-8 years, as indexed by parent-reported internalizing problems and child self-reported anxiety and depressive symptoms (N = 268-418). RESULTS: Greater maternal childhood neglect was indirectly associated with greater internalizing problems serially through a pathway of worse maternal prenatal and postnatal mental health (greater maternal anxiety and depressive symptoms). Worse maternal postnatal mental health was also uniquely associated with more negative child frontoamygdala resting-state functional connectivity, over and above maternal childhood trauma (both neglect and abuse) and prenatal mental health. More negative frontoamygdala functional connectivity was, in turn, associated with poorer child emotional health outcomes. CONCLUSIONS: Findings from the current study provide support for the existence of intergenerational influences of parental exposure to childhood trauma on childhood risk for psychopathology in the next generation and point to the importance of maternal factors proximal to the second generation (maternal prenatal and postnatal mental health) in determining the intergenerational impact of maternal early experiences.


Asunto(s)
Experiencias Adversas de la Infancia , Salud Mental , Femenino , Embarazo , Niño , Humanos , Estudios Prospectivos , Salud Infantil , Madres/psicología
9.
Br J Neurosurg ; 37(5): 986-999, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33960863

RESUMEN

Lesions of the paediatric cranial vault are diverse both in their presentation and aetiology. As such, they pose a diagnostic challenge to the paediatric neurosurgeon and neuroradiologist. In this article, we delineate the spectrum of paediatric calvarial pathology into four distinct groups: (1) lytic lesion(s); (2) focal sclerotic lesion(s); (3) diffuse cranial vault sclerosis; and (4) abnormal shape of the cranial vault. It is our aim that this more pragmatic, algorithmic approach may mitigate diagnostic uncertainty and aid the more accurate diagnosis of paediatric calvarial lesions.


Asunto(s)
Craneosinostosis , Niño , Humanos , Lactante , Craneosinostosis/patología , Craneosinostosis/cirugía , Cráneo/diagnóstico por imagen , Cráneo/cirugía
10.
Mol Psychiatry ; 26(8): 3956-3969, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-31772302

RESUMEN

Social interaction and communication are evolutionary conserved behaviours that are developed in mammals to establish partner cognition. Deficit in sociability has been represented in human patients and animal models of neurodevelopmental disorders, which are connected with genetic variants of synaptic glutamate receptors and associated PDZ-binding proteins. However, it remains elusive how these key proteins are specialized in the cellular level for the initial social behaviour during postnatal developmental stage. Here we identify a hippocampal CA3 specifically expressed PDZ scaffold protein Lnx1 required for initial social behaviour. Through gene targeting we find that Lnx1 deficiency led to a hippocampal subregional disorder in neuronal activity and social memory impairments for partner discrimination observed in juvenile mice which also show cognitive defects in adult stage. We further demonstrate that Lnx1 deletion causes NMDA receptor (NMDAR) hypofunction and this is attributable to decreased GluN2B expression in PSD compartment and disruption of the Lnx1-NMDAR-EphB2 complex. Specific restoration of Lnx1 or EphB2 protein in the CA3 area of Lnx1-/- mice rescues the defective synaptic function and social memory. These findings thus reveal crucial roles of postsynaptic NMDAR multiprotein complex that regulates the formation of initial social memory during the adolescent period.


Asunto(s)
Región CA3 Hipocampal/fisiología , Memoria , Receptores de N-Metil-D-Aspartato , Conducta Social , Ubiquitina-Proteína Ligasas , Animales , Trastornos de la Memoria/genética , Ratones , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/metabolismo , Transducción de Señal , Ubiquitina-Proteína Ligasas/metabolismo
11.
Exp Cell Res ; 405(2): 112707, 2021 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-34153301

RESUMEN

Aberrant NF-κB activation and neutrophil extracellular traps (NETs) are associated with breast cancer progression. How NF-κB and NETs modulate each other in breast cancer development remains unclear. Here, we found that NETs induced by phorbol 12-myristate 13-acetate promote breast cancer cell progression. In turn, cancer cells-derived factors, such as IL-8 and granulocyte colony-stimulating factor, stimulate neutrophils to form NETs. Mechanistically, NETs increased the interaction of NF-κB essential modifier (NEMO) with IκB kinase (IKK)α/ß and enhanced NF-κB activation. We then employed a cell-permeable peptide corresponding to the NEMO-binding domain (NBD) of IKKα/ß, termed NBD peptide, which disrupts NETs-mediated NEMO interaction with IKKα/ß and abolished NF-κB activation in vitro. NBD peptide also reduced IL-8 level and NETs formation, and suppressed primary tumor growth and/or lung metastasis in human breast cancer mouse xenograft models and mouse spontaneous breast cancer model. Blockade of NET formation using a peptidylarginine deiminase 4 (PAD4) pharmacologic inhibitor decreased NF-κB activation and tumor metastasis. Collectively, these data suggest that NF-κB associates with NETs to form a positive loop facilitating breast tumor progression and metastasis, and that selective inhibition of NF-κB and PAD4-dependent NETs provides an effective therapeutic approach for treating breast cancer.


Asunto(s)
Neoplasias Pulmonares/patología , FN-kappa B/metabolismo , Metástasis de la Neoplasia/patología , Neutrófilos/metabolismo , Trampas Extracelulares/metabolismo , Xenoinjertos/patología , Humanos , Transducción de Señal/fisiología , Trasplante Heterólogo/métodos
12.
Eur J Neurosci ; 54(2): 4621-4637, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34125467

RESUMEN

The complex interaction between brain and behaviour in language disorder is well established. Yet to date, the imaging literature in the language disorder field has continued to pursue heterogeneous and relatively small clinical cross-sectional samples, with emphasis on cortical structures and volumetric analyses of subcortical brain structures. In our current work, we aimed to go beyond this state of knowledge to focus on the microstructural features of subcortical brain structures (specifically the caudate nucleus) in a large cohort of neonates and study its association with emerging language skills at 24 months. Variations in neonatal brain microstructure could be interpreted as a proxy for in utero brain development. As language development is highly dependent on cognitive function and home literacy environment, we also examined their effect on the caudate-language function relationship utilizing a conditional process model. Our findings suggest that emerging language development at 24 months is influenced by the degree of left lateralization of neonatal caudate microstructure, indexed by diffusion tensor imaging (DTI)-derived fractional anisotropy (FA). FA is an indirect measure of neuronal and dendritic density within grey matter structures. We also found that the caudate-language function relationship is partially mediated by cognitive function. The conditional indirect effect of left caudate FA on language composite score through cognitive function was only statistically significant at low levels of home literacy score (-1 standard deviation [SD]). The authors proposed that this may be related to 'compensatory' development of cognitive skills in less favourable home literacy environments.


Asunto(s)
Imagen de Difusión Tensora , Sustancia Blanca , Encéfalo/diagnóstico por imagen , Estudios Transversales , Sustancia Gris , Humanos , Recién Nacido , Desarrollo del Lenguaje
13.
Biochem Biophys Res Commun ; 565: 64-71, 2021 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-34098313

RESUMEN

Neutrophil extracellular traps (NETs) are extracellular webs of DNA, histones and granular contents that are released by neutrophils to control infections. However, NETs that is not properly regulated can propagate inflammation and thrombosis. It was recognized that viruses can induce NETs. As a synthetic analog of viral double-stranded (ds) RNA, polyinosinic-polycytidylic acid [poly(I:C)] is known to induce inflammation and thrombosis. However, whether and how poly(I:C) modulates NETs remains unclear. Here, we have demonstrated that poly(I:C) induced extracellular DNA traps in human neutrophils in a dose-dependent manner. Further, poly(I:C) or dsRNA virus elevated the levels of myeloperoxidase-DNA complexes and citrullinated histone H3, which are specific markers of NETs, in both neutrophil supernatants and mouse plasma. Interestingly, a potent peptidylarginine deiminase 4 (PAD4) inhibitor, BB-CL-Amidine (BB-CLA) or PAD4 knockdown effectively prevented poly(I:C)-induced NETs formation and release. In addition, BB-CLA abrogated poly(I:C)-triggered neutrophil activation and infiltration, and vascular permeability in lungs. BB-CLA also attenuated poly(I:C)-induced thrombocytopenia in circulation, fibrin deposition and thrombus formation in tissues. Taken together, these results suggest that viral mimetic poly(I:C) may induce NETs-dependent inflammation and thrombosis through PAD4, and that inhibiting PAD4 may become a good strategy to protect against viral infection-caused inflammation/thrombosis-related pathological conditions of diseases.


Asunto(s)
Trampas Extracelulares/efectos de los fármacos , Inflamación/metabolismo , Neutrófilos/efectos de los fármacos , Poli I-C/farmacología , Arginina Deiminasa Proteína-Tipo 4/metabolismo , Trombosis/metabolismo , Amidinas/farmacología , Animales , Células Cultivadas , Chlorocebus aethiops , Humanos , Inflamación/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Activación Neutrófila/efectos de los fármacos , Neutrófilos/metabolismo , Arginina Deiminasa Proteína-Tipo 4/antagonistas & inhibidores , Trombosis/patología
14.
Int J Obes (Lond) ; 45(11): 2396-2403, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34282269

RESUMEN

BACKGROUND: Neonatal adiposity is associated with a higher risk of obesity and cardiometabolic risk factors in later life. It is however unknown if central food intake regulating networks in the ventral striatum are altered with in-utero abdominal growth, indexed by neonatal adiposity in our current study. We aim to examine the relationship between striatal microstructure and abdominal adipose tissue compartments (AATCs) in Asian neonates from the Growing Up in Singapore Toward healthy Outcomes mother-offspring cohort. STUDY DESIGN: About 109 neonates were included in this study. Magnetic resonance imaging (MRI) was performed for the brain and abdominal regions between 5 to 17 days of life. Diffusion-weighted imaging of the brain was performed for the derivation of caudate and putamen fractional anisotropy (FA). Abdominal imaging was performed to quantify AATCs namely superficial subcutaneous adipose tissue (sSAT), deep subcutaneous adipose tissue (dSAT), and internal adipose tissue (IAT). Absolute and percentage adipose tissue of total abdominal volume (TAV) were calculated. RESULTS: We showed that AATCs at birth were significantly associated with increased FA in bilateral ventral caudate heads which are part of the ventral striatum (sSAT: ßleft = 0.56, p < 0.001; ßright = 0.65, p < 0.001, dSAT: ßleft = 0.43, p < 0.001; ßright = 0.52, p < 0.001, IAT: ßleft = 0.30, p = 0.005; ßright = 0.32, p = 0.002) in neonates with low birth weights adjusted for gestational age. CONCLUSIONS: Our study provides preliminary evidence of a potential relationship between neonatal adiposity and in-utero programming of the ventral striatum, a brain structure that governs feeding behavior.


Asunto(s)
Grasa Abdominal/metabolismo , Peso al Nacer/fisiología , Núcleo Caudado/anomalías , Grasa Abdominal/diagnóstico por imagen , Grasa Abdominal/fisiopatología , Índice de Masa Corporal , Núcleo Caudado/fisiopatología , Femenino , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Recién Nacido , Imagen por Resonancia Magnética/métodos , Masculino , Singapur
15.
Acta Neurochir (Wien) ; 163(7): 1935-1939, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33999264

RESUMEN

Gamma knife radiosurgery (GKS), a technique which involves delivery of a high dose of radiation to a precisely defined target, has become the predominant treatment option for brain metastases (BM) because of its high effectiveness and relatively minimal toxicity. Herein, we report a case of late-onset radiation-induced edema around an asymptomatic cyst, more than 20 years after salvage GKS, with 27 years of imaging follow-up, allowing the description of the evolutionary trajectory of these relatively rare complications. Our reported case also demonstrated the benign nature of delayed cyst formation (DCF), emphasizing that observation alone is reasonable for asymptomatic patients.


Asunto(s)
Neoplasias Encefálicas , Radiocirugia , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirugía , Quistes/diagnóstico por imagen , Quistes/etiología , Estudios de Seguimiento , Humanos , Radiocirugia/efectos adversos , Estudios Retrospectivos , Terapia Recuperativa , Resultado del Tratamiento
16.
Physiol Mol Biol Plants ; 27(7): 1455-1468, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34366589

RESUMEN

DNA methylation is the most important epigenetic modification involved in many essential biological processes. MET1 is one of DNA methyltransferases that affect the level of methylation in the entire genome. To explore the effect of MET1 gene silencing on gene expression profile of Chrysanthemum × morifolium 'Zijingling'. The stem section and leaves at the young stage were taken for transcriptome sequencing. MET1-RNAi leaves had 8 differentially expressed genes while 156 differentially expressed genes were observed in MET1-RNAi stem compared with control leaves and stem. These genes encode many key proteins in plant biological processes, such as transcription factors, signal transduction mechanisms, secondary metabolite synthesis, transport and catabolism and interaction. In general, 34.58% of the differentially expressed genes in leaves and stems were affected by the reduction of the MET1 gene. The differentially expressed genes in stem and leaves of transgenic plants went through significant changes. We found adequate amount of candidate genes associated with flowering, however, the number of genes with significant differences between transgenic and control lines was not too high. Several flowering related genes were screened out for gene expression verification and all of them were obseved as consistent with transcriptome data. These candidate genes may play important role in flowering variation of chrysanthemum. This study reveals the mechanism of CmMET1 interference on the growth and development of chrysanthemum at the transcriptional level, which provides the basis for further research on the epigenetic regulation mechanism in flower induction and development. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12298-021-01022-1.

17.
Plant Biotechnol J ; 18(3): 814-828, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31479566

RESUMEN

The diploid wild cotton species Gossypium australe possesses excellent traits including resistance to disease and delayed gland morphogenesis, and has been successfully used for distant breeding programmes to incorporate disease resistance traits into domesticated cotton. Here, we sequenced the G. australe genome by integrating PacBio, Illumina short read, BioNano (DLS) and Hi-C technologies, and acquired a high-quality reference genome with a contig N50 of 1.83 Mb and a scaffold N50 of 143.60 Mb. We found that 73.5% of the G. australe genome is composed of various repeat sequences, differing from those of G. arboreum (85.39%), G. hirsutum (69.86%) and G. barbadense (69.83%). The G. australe genome showed closer collinear relationships with the genome of G. arboreum than G. raimondii and has undergone less extensive genome reorganization than the G. arboreum genome. Selection signature and transcriptomics analyses implicated multiple genes in disease resistance responses, including GauCCD7 and GauCBP1, and experiments revealed induction of both genes by Verticillium dahliae and by the plant hormones strigolactone (GR24), salicylic acid (SA) and methyl jasmonate (MeJA). Experiments using a Verticillium-resistant domesticated G. barbadense cultivar confirmed that knockdown of the homologues of these genes caused a significant reduction in resistance against Verticillium dahliae. Moreover, knockdown of a newly identified gland-associated gene GauGRAS1 caused a glandless phenotype in partial tissues using G. australe. The G. australe genome represents a valuable resource for cotton research and distant relative breeding as well as for understanding the evolutionary history of crop genomes.


Asunto(s)
Resistencia a la Enfermedad , Gossypium/genética , Australia , Diploidia , Regulación de la Expresión Génica de las Plantas , Técnicas de Silenciamiento del Gen , Morfogénesis , Enfermedades de las Plantas/genética
18.
Pediatr Blood Cancer ; 67(11): e28635, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32770654

RESUMEN

BACKGROUND: The advent of chimeric antigen receptor (CAR) T-cell therapy has created a paradigm shift in the management of patients with refractory B-cell acute lymphocytic leukaemia (ALL). The aim of this study is to correlate imaging findings of CAR T-cell therapy related neurotoxicity with clinical course and eventual clinical outcome, with the hope that it will bring us a step closer to the identification of potential imaging biomarkers that may allow more accurate prognostication and risk stratification of patients. PROCEDURE: Our imaging database was queried from January 2018 to April 2020 to identify paediatric patients who fulfil the following criteria: (a) diagnosed with ALL, (b) underwent CAR T-cell therapy, and (c) had magnetic resonance imaging (MRI) brain studies performed before and after CAR T-cell therapy. A total of seven patients were included and all MRI studies were analysed by a paediatric neuroradiologist for the presence of acute neuroimaging findings post CAR T-cell infusion. Acute neuroimaging findings are defined as new imaging findings detected within 28 days of CAR T-cell infusion. RESULTS: Three out of four patients with acute neuroimaging findings had sustained complete remission for more than 6 months, while all three patients without acute neuroimaging findings had positive minimal residual disease (MRD) within 1 month. Both patients with acute diffuse leptomeningeal enhancement showed clinical improvement within 1-2 days. CONCLUSIONS: Acute neuroimaging findings may be a potential imaging biomarker for peak neurotoxicity and treatment response, and it is not necessarily associated with poor outcome, as previously reported.


Asunto(s)
Inmunoterapia Adoptiva/efectos adversos , Síndromes de Neurotoxicidad/etiología , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Receptores de Antígenos de Linfocitos T/inmunología , Niño , Estudios de Seguimiento , Humanos , Neuroimagen/métodos , Síndromes de Neurotoxicidad/diagnóstico por imagen , Síndromes de Neurotoxicidad/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Pronóstico , Estudios Retrospectivos
19.
Neuropediatrics ; 51(1): 6-21, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31634934

RESUMEN

Inherited neurotransmitter disorders are rare neurometabolic conditions which encompass genetic disorders of neurotransmitter metabolism or transport. The clinical manifestations of these rare disorders are often nonspecific, ranging from encephalopathies and seizures to movement disorders. As a consequence, neurotransmitter disorders are underrecognized and often misdiagnosed. Accurate and timely diagnosis is, however, of utmost importance, given the availability of therapeutic strategies. A high index of clinical suspicion and familiarity with the neuroimaging phenotypes is therefore crucial. While the imaging features of various neurotransmitter disorders often overlap and are nonspecific, imaging can be helpful in providing useful clues to guide the diagnostic algorithm for uncommon conditions in a neonate presenting with nonspecific neurological symptoms. In this review paper, we aim to bring together current knowledge of neuroimaging phenotypes associated with inherited (primary) disorders of neurotransmitter biosynthesis. Magnetic resonance imaging phenotypes of disorders of monoamine biosynthesis, primary cerebral folate deficiency, disorders of pyridoxine metabolism, disorders of gamma-aminobutyric acid metabolism, nonketotic hyperglycinemia (glycine encephalopathy), disorders of serine biosynthesis, and cerebral creatine deficiency syndrome will be discussed and illustrated with case examples.


Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos , Monoaminas Biogénicas , Encefalopatías Metabólicas , Neuroimagen , Errores Innatos del Metabolismo de los Aminoácidos/diagnóstico por imagen , Errores Innatos del Metabolismo de los Aminoácidos/metabolismo , Errores Innatos del Metabolismo de los Aminoácidos/patología , Errores Innatos del Metabolismo de los Aminoácidos/fisiopatología , Monoaminas Biogénicas/metabolismo , Encefalopatías Metabólicas/diagnóstico por imagen , Encefalopatías Metabólicas/metabolismo , Encefalopatías Metabólicas/patología , Encefalopatías Metabólicas/fisiopatología , Humanos
20.
Neuroradiology ; 62(7): 903, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32424710

RESUMEN

The original version of this article unfortunately contained a referencing omission. Figure 11 is reused from the original publication of Figure 10 of Gunny and Lin [1].

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