Microbial colonization of mammals is an evolution-driven process that modulate host physiology, many of which are associated with immunity and nutrient intake. Here, we report that colonization by ...gut microbiota impacts mammalian brain development and subsequent adult behavior. Using measures of motor activity and anxiety-like behavior, we demonstrate that germ free (GF) mice display increased motor activity and reduced anxiety, compared with specific pathogen free (SPF) mice with a normal gut microbiota. This behavioral phenotype is associated with altered expression of genes known to be involved in second messenger pathways and synaptic long-term potentiation in brain regions implicated in motor control and anxiety-like behavior. GF mice exposed to gut microbiota early in life display similar characteristics as SPF mice, including reduced expression of PSD-95 and synaptophysin in the striatum. Hence, our results suggest that the microbial colonization process initiates signaling mechanisms that affect neuronal circuits involved in motor control and anxiety behavior.
Few population-based studies of cerebral palsy have been done in low-income and middle-income countries. We aimed to examine cerebral palsy prevalence and subtypes, functional impairments, and ...presumed time of injury in children in Uganda.
In this population-based study, we used a nested, three-stage, cross-sectional method (Iganga-Mayuge Health and Demographic Surveillance System HDSS) to screen for cerebral palsy in children aged 2–17 years in a rural eastern Uganda district. A specialist team confirmed the diagnosis and determined the subtype, motor function (according to the Gross Motor Function Classification System GMFCS), and possible time of brain injury for each child. Triangulation and interviews with key village informants were used to identify additional cases of suspected cerebral palsy. We estimated crude and adjusted cerebral palsy prevalence. We did χ2 analyses to examine differences between the group screened at stage 1 and the entire population and regression analyses to investigate associations between the number of cases and age, GMFCS level, subtype, and time of injury.
We used data from the March 1, 2015, to June 30, 2015, surveillance round of the Iganga-Mayuge HDSS. 31 756 children were screened for cerebral palsy, which was confirmed in 86 (19%) of 442 children who screened positive in the first screening stage. The crude cerebral palsy prevalence was 2·7 (95% CI 2·2–3·3) per 1000 children, and prevalence increased to 2·9 (2·4–3·6) per 1000 children after adjustment for attrition. The prevalence was lower in older (8–17 years) than in younger (<8 years) children. Triangulation added 11 children to the cohort. Spastic unilateral cerebral palsy was the most common subtype (45 46% of 97 children) followed by bilateral cerebral palsy (39 40% of 97 children). 14 (27%) of 51 children aged 2–7 years had severe cerebral palsy (GMFCS levels 4–5) compared with only five (12%) of 42 children aged 8–17 years. Few children (two 2% of 97) diagnosed with cerebral palsy were born preterm. Post-neonatal events were the probable cause of cerebral palsy in 24 (25%) of 97 children.
Cerebral palsy prevalence was higher in rural Uganda than in high-income countries (HICs), where prevalence is about 1·8–2·3 cases per 1000 children. Children younger than 8 years were more likely to have severe cerebral palsy than older children. Fewer older children than younger children with cerebral palsy suggested a high mortality in severely affected children. The small number of preterm-born children probably resulted from low preterm survival. About five times more children with post-neonatal cerebral palsy in Uganda than in HICs suggested that cerebral malaria and seizures were prevalent risk factors in this population.
Swedish Research Council, Promobilia.
Executive functions are frequently a weakness in children born preterm. We examined associations of executive functions and general cognitive abilities with brain structure in preterm born ...adolescents who were born with appropriate weight for gestational age and who have no radiological signs of preterm brain injury on neuroimaging.
The Stockholm Neonatal Project (SNP) is a longitudinal, population-based study of children born preterm (<36 weeks of gestation) with very low birth weight (<1501g) between 1988-1993. At age 18 years (mean 18 years, SD 2 weeks) 134 preterm born and 94 full term participants underwent psychological assessment (general intelligence, executive function measures). Of these, 71 preterm and 63 full term participants underwent Magnetic Resonance Imaging (MRI) at mean 15.2 years (range 12-18 years), including 3D T1-weighted images for volumetric analyses and Diffusion Tensor Imaging (DTI) for assessment of white matter microstructure. Group comparisons of regional grey and white matter volumes and fractional anisotropy (FA, as a measure of white matter microstructure) and, within each group, correlation analyses of cognitive measures with MRI metrics were carried out.
Significant differences in grey and white matter regional volumes and widespread differences in FA were seen between the two groups. No significant correlations were found between cognitive measures and brain volumes in any group after correction for multiple comparisons. However, there were significant correlations between FA in projection fibres and long association fibres, linking frontal, temporal, parietal, and occipital lobes, and measures of executive function and general cognitive abilities in the preterm born adolescents, but not in the term born adolescents.
In persons born preterm, in the absence of perinatal brain injury on visual inspection of MRI, widespread alterations in regional brain tissue volumes and microstructure are present in adolescence/young adulthood. Importantly, these alterations in WM tracts are correlated with measures of executive function and general cognitive abilities. Our findings suggest that disturbance of neural pathways, rather than changes in regional brain volumes, are involved in the impaired cognitive functions.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Using diffusion tensor imaging, we investigated effects of piano practicing in childhood, adolescence and adulthood on white matter, and found positive correlations between practicing and fiber tract ...organization in different regions for each age period. For childhood, practicing correlations were extensive and included the pyramidal tract, which was more structured in pianists than in non-musicians. Long-term training within critical developmental periods may thus induce regionally specific plasticity in myelinating tracts.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Cerebral palsy (CP) is one of the most common childhood-onset motor disabilities, attributed to injuries of the immature brain in the foetal or early postnatal period. The underlying mechanisms are ...poorly understood, rendering prevention and treatment strategies challenging. The aim of the present study was to establish a mouse model of CP for preclinical assessment of new interventions. For this purpose, we explored the impact of a double neonatal insult (i.e. systemic inflammation combined with hypoxia) on behavioural and cellular outcomes relevant to CP during the prepubertal to adolescent period of mice. Pups were subjected to intraperitoneal lipopolysaccharide (LPS) injections from postnatal day (P) 3 to P6 followed by hypoxia at P7. Gene expression analysis at P6 revealed a strong inflammatory response in a brain region-dependent manner. A comprehensive battery of behavioural assessments performed between P24 and P47 showed impaired limb placement and coordination when walking on a horizontal ladder in both males and females. Exposed males also displayed impaired performance on a forelimb skilled reaching task, altered gait pattern and increased exploratory activity. Exposed females showed a reduction in grip strength and traits of anxiety-like behaviour. These behavioural alterations were not associated with gross morphological changes, white matter lesions or chronic inflammation in the brain. Our results indicate that the neonatal double-hit with LPS and hypoxia can induce subtle long-lasting deficits in motor learning and fine motor skills, which partly reflect the symptoms of children with CP who have mild gross and fine motor impairments.
Studies from high-income countries reported reduced life expectancy in children with cerebral palsy (CP), while no population-based study has evaluated mortality of children with CP in sub-Saharan ...Africa. This study aimed to estimate the mortality rate (MR) of children with CP in a rural region of Uganda and identify risk factors and causes of death (CODs).
This population-based, longitudinal cohort study was based on data from Iganga-Mayuge Health and Demographic Surveillance System in eastern Uganda. We identified 97 children (aged 2-17 years) with CP in 2015, whom we followed to 2019. They were compared with an age-matched cohort from the general population (n = 41 319). MRs, MR ratios (MRRs), hazard ratios (HRs), and immediate CODs were determined. MR was 3952 per 100 000 person years (95% CI 2212-6519) in children with CP and 137 per 100 000 person years (95% CI 117-159) in the general population. Standardized MRR was 25·3 in the CP cohort, compared with the general population. In children with CP, risk of death was higher in those with severe gross motor impairments than in those with milder impairments (HR 6·8; p = 0·007) and in those with severe malnutrition than in those less malnourished (HR = 3·7; p = 0·052). MR was higher in females in the CP cohort, with a higher MRR in females (53·0; 95% CI 26·4-106·3) than in males (16·3; 95% CI 7·2-37·2). Age had no significant effect on MR in the CP cohort, but MRR was higher at 10-18 years (39·6; 95% CI 14·2-110·0) than at 2-6 years (21·0; 95% CI 10·2-43·2). Anaemia, malaria, and other infections were the most common CODs in the CP cohort.
Risk of premature death was excessively high in children with CP in rural sub-Saharan Africa, especially in those with severe motor impairments or malnutrition. While global childhood mortality has significantly decreased during recent decades, this observed excessive mortality is a hidden humanitarian crisis that needs to be addressed.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Evidence from cross-sectional human studies, and preliminary microbial-based intervention studies, have implicated the microbiota-gut-brain axis in the neurobiology of autism spectrum disorder (ASD). ...Using a prospective longitudinal study design, we investigated the developmental profile of the fecal microbiota and metabolome in infants with (n = 16) and without (n = 19) a family history of ASD across the first 36 months of life. In addition, the general developmental levels of infants were evaluated using the Mullen Scales of Early Learning (MSEL) test at 5 and 36 months of age, and with ADOS-2 at 36 months of age. At 5 months of age, infants at elevated-likelihood of ASD (EL) harbored less Bifidobacterium and more Clostridium and Klebsiella species compared to the low-likelihood infants (LL). Untargeted metabolic profiling highlighted that LL infants excreted a greater amount of fecal γ-aminobutyric acid (GABA) at 5 months, which progressively declined with age. Similar age-dependent patterns were not observed in the EL group, with GABA being consistently low across all timepoints. Integrated microbiome-metabolome analysis showed a positive correlation between GABA and Bifidobacterium species and negative associations with Clostridium species. In vitro experiments supported these observations demonstrating that bifidobacteria can produce GABA while clostridia can consume it. At the behavioral level, there were no significant differences between the EL and LL groups at 5 months. However, at 36 months of age, the EL group had significantly lower MSEL and ADOS-2 scores compared to the LL group. Taken together, the present results reveal early life alterations in gut microbiota composition and functionality in infants at elevated-likelihood of ASD. These changes occur before any behavioral impairments can be detected, supporting a possible role for the gut microbiota in emerging behavioral variability later in life.
We used functional magnetic resonance imaging (fMRI) to identify brain areas involved in auditory rhythm perception. Participants listened to three rhythm sequences that varied in temporal ...predictability. The most predictable sequence was an isochronous rhythm sequence of a single interval (ISO). The other two sequences had nine intervals with unequal durations. One of these had interval durations of integer ratios relative to the shortest interval (METRIC). The other had interval durations of non-integer ratios relative to the shortest interval (NON-METRIC), and was thus perceptually more complex than the other two. In addition, we presented unpredictable sequences with randomly distributed intervals (RAN). We tested two hypotheses. Firstly, that areas involved in motor timing control would also process the temporal predictability of sensory cues. Therefore, there was no active task included in the experiment that could influence the participant perception or induce motor preparation. We found that dorsal premotor cortex (PMD), SMA, preSMA, and lateral cerebellum were more active when participants listen to rhythm sequences compared to random sequences. The activity pattern in supplementary motor area (SMA) and preSMA suggested a modulation dependent on sequence predictability, strongly suggesting a role in temporal sensory prediction. Secondly, we hypothesized that the more complex the rhythm sequence, the more it would engage short-term memory processes of the prefrontal cortex. We found that the superior prefrontal cortex was more active when listening to METRIC and NON-METRIC compared to ISO. We argue that the complexity of rhythm sequences is an important factor in modulating activity in many of the rhythm areas. However, the difference in complexity of our stimuli should be regarded as continuous.
Although, there is no population-level data in Ethiopia, a previous retrospective hospital-based study identified CP as the most common developmental disability in children. The overall aim of this ...study is to describe the clinical spectrum of CP in Tikur Anbessa Specialized Hospital in Addis Ababa, including CP subtype, gross and fine motor function, presence and pattern of associated impairments, and possible risk factors in children aged 2 to 18 years.
A hospital-based descriptive cross-sectional study conducted- July - September of 2018 among 207 children with suspected motor symptoms. The Surveillance of CP in Europe (SCPE) decision tree was used as a guideline for inclusion and evaluation was by standardized questionnaire and clinical examination. Descriptive, bivariate and multivariate statistical analyses, Chi-square test, crudes association and adjusted odds ratio with 95% confidence interval employed.
One hundred seventy four children who fulfilled the clinical criteria were included. Half (50.6%) were under the age of 5 years with a mean age of 5.6 (SD 3.6) years; 55.2 were male. The majority had bilateral spastic CP (60.4%) followed by unilateral spastic CP 21.8%, dyskinetic CP 10.4%, and ataxic CP 3.4%; 4% were unclassifiable. Of the children, 95.4% had speech difficulty, 87.4% learning disabilities, 60.9% epilepsy, 24.7% visual impairment and 8.6% hearing impairment. On gross motor function (GMFCS) and manual ability (MACS) classification systems, 75.3% of the children had level IV and V functional impairment. More than 80% of the mothers had complications during delivery Half of the neonates did not cry immediately after birth,44% were resuscitated with bag mask ventilation at birth and 64% immediately admitted to NICU. During the first month of life, 50% had infection, 62% had trouble feeding, 49.4% had difficulty breathing, 35% had seizure and 13.8% had jaundice.
The severe forms of CP predominate; most children are dependent on their parents for routine activities of daily living and cannot communicate well. Multidisciplinary care approaches and focused functional habilitation services are needed. Causal relationships cannot be drawn from these data but findings make a strong argument for improving maternal and child health care.
The aim of this study was to identify changes in brain activity associated with the increase in working memory (WM) capacity that occurs during childhood and early adulthood. Functional MRI (fMRI) ...was used to measure brain activity in subjects between 9 and 18 years of age while they performed a visuospatial WM task and a baseline task. During performance of the WM task, the older children showed higher activation of cortex in the superior frontal and intraparietal cortex than the younger children did. A second analysis found that WM capacity was significantly correlated with brain activity in the same regions. These frontal and parietal areas are known to be involved in the control of attention and spatial WM. The development of the functionality in these areas may play an important role in cognitive development during childhood.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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