Child characteristics associated with child quality of life and parenting stress in Angelman syndrome.

BACKGROUND: Angelman syndrome (AS) is a rare neurodevelopmental disorder characterised by severe intellectual disability, movement disorder, epilepsy, sleeping problems, and behavioural issues. Little is known on child health-related quality of life (HRQoL) in AS. AS family studies have reported elevated parenting stress and a high impact of the child's syndrome on the parent. It is unclear which factors influence child HRQoL and parenting stress/impact in AS. METHODS: We collected data prospectively through standardised clinical assessments of children with AS at the ENCORE Expertise centre for Angelman Syndrome at the Erasmus MC Sophia Children's Hospital. A linear regression analysis was conducted for the following outcome variables: (1) child HRQoL (Infant and Toddler Quality of Life Questionnaire); (2) the impact of the child's syndrome on the parent (Infant and Toddler Quality of Life Questionnaire); and (3) parenting stress (Parenting Stress Index). Predictor variables were child genotype, epilepsy, sleeping problems (Sleep Disturbance Scale for Children), cognitive developmental level (Bayley Cognition Scale), autistic features (Autism Diagnostic Observation Schedule) and emotional/behavioural problems (Child Behaviour Checklist). Covariates were sex, age and socio-economic status. RESULTS: The study sample consisted of 73 children with AS, mean age = 9.1 years, range = 2-18 years. Emotional/behavioural problems were the strongest significant predictor of lowered child HRQoL. Internalising problems were driving this effect. In addition, having the deletion genotype and higher age was related to lower child HRQoL. Sleeping problems were related to a higher impact of the child's syndrome on the parent. Finally, emotional/behavioural problems were associated with higher parenting stress. Cognitive developmental level, autistic features and epilepsy were not a significant predictor of child HRQoL and parenting stress/impact. CONCLUSIONS: These results suggest that interventions aimed at increasing child HRQoL and decreasing parenting stress/impact in AS should focus on child emotional/behavioural problems and sleeping problems, using a family-centred approach.

Growing up with Fragile X Syndrome: Concerns and Care Needs of Young Adult Patients and Their Parents.

Little is known about care needs of young adults with Fragile X Syndrome (FXS). Patient-driven information is needed to improve understanding and support of young adults with FXS. A qualitative study was performed in 5 young adult patients (aged 18-30), and 33 parents of young adults. Concerns and care needs were categorized using the International Classification of Functioning, Disability, and Health. Results indicated concerns on 14 domains for males, and 13 domains for females, including physical, psychological and socio-economical issues. In both groups parents reported high stress levels and a lack of knowledge of FXS in adult care providers. This study revealed concerns on various domains, requiring gender-specific, multidisciplinary transitional care and adult follow-up for patients with FXS.

[Fragile X syndrome: new therapeutic strategies]. / Fragiele-X-syndroom: nieuwe therapeutische strategieën.

BACKGROUND: Fragile X syndrome (fxs) is the most common hereditary cause of intellectual disability and autism spectrum disorders. Targeted treatment is currently lacking. In the past decades an enormous amount of knowledge has been obtained concerning the involved molecular pathways, introducing potential targets for disease modifying therapy.
AIM: To present an overview of the development of targeted treatment for fxs.
METHOD: Several important publications were collected and indexed.
RESULTS: While preclinical animal model studies with targeted interventions are promising, the translation to the clinic has been disappointing.
CONCLUSION: Targeted treatment for fxs is necessary and could be applied in other causes of autism spectrum disorders and intellectual disability. Factors relating to translation, study design and outcome measures are possibly contributing to the disappointing results. The clustering of patient care in a center of expertise is required to clinically implement future therapeutic strategies and to facilitate research. In addition, this improves patient care, one example being the recent medical guideline for children with fxs.

Chloride-depletion of photosynthetic water oxidase. No proton release during the second oxidation step, S2*==>S3*, and a transmembrane radical pair recombination from the third on.

Chloride depletion blocks the normal four-step progress of photosynthetic water oxidation. We studied proton release in chloride-depleted thylakoids which were dark-adapted and excited by flashing light. Proton release was blocked from the second flash on, possibly leaving an uncompensated positive charge in the catalytic centre. The reduction of P+680 by Tyrz was still very rapid (<< 10 microseconds). From the third flash on, P+680 was reduced more slowly (70 microseconds/200 microseconds), and by an electrogenic back-reaction. The uncompensated positive charge may be the reason why the rapid reduction of P+680 by Tyrz is prevented and the transmembrane charge-pair recombination is facilitated.

Differentiation of granule cells in relation to GABAergic neurons in the rat fascia dentata. Combined Golgi/EM and immunocytochemical studies.

Golgi impregnation was used to study the dendritic differentiation of granule cells in the rat fascia dentata. The impregnated granule cells were gold-toned allowing for a fine structural study of the same identified neurons and of the input synapses onto their cell bodies and dendrites. Due to the long postnatal formation of these cells it was possible to describe a sequence of maturational stages coexisting on the same postnatal day (P5). Characteristic features of the dendritic development of granule cells were i) occurrence of varicose swellings along the dendrites, ii) growth cones on dendritic tips, iii) transient formation of basal dendrites, and iv) progressive development of dendritic spines. Incoming synapses on the differentiating granule cells were mainly found on dendritic shafts. Their membrane specializations were symmetric. At least some of these symmetric synapses were GABAergic because immunostaining of Vibratome sections from the same postnatal stage (P5) demonstrated a well-developed GABAergic axon plexus in the fascia dentata (antibodies against glutamate decarboxylase (GAD), the GABA synthesizing enzyme). Electron microscopy of the immunostained axon plexus revealed numerous GABAergic terminals that formed symmetric synaptic contacts, mainly on shafts of differentiating dendrites but also on cell bodies of granule cells. Our results thus indicate that the plexus of inhibitory GABAergic axons is already well developed at a stage when the target neurons, the granule cells, are still being formed.

Fine structure and synaptic connections of identified neurons in the rat fascia dentata.

A survey is given of the synaptic connections of identified neurons in the rat fascia dentata based on our own Golgi/electron microscopic and light and electron microscopic immunocytochemical findings as well as on results obtained from the literature. The report largely deals with the dominating cell type in the region, the dentate granule cell. Of the various types of hilar cells, the GABAergic neurons, particularly the inhibitory basket cells, are taken into account. Differences in fine structure between granule cells and basket cells as well as mutual synaptic connections between these two types of dentate neurons are elaborated. This survey may provide a basis for further neurophysiological and pharmacological studies on these cells.

Neurogenesis of GABAergic neurons in the rat dentate gyrus: a combined autoradiographic and immunocytochemical study.

Neurogenesis of GABAergic neurons in the rat area dentata was studied combining [3H]thymidine autoradiography with immunostaining for glutamate decarboxylase (GAD), the gamma-aminobutyric acid (GABA) synthesizing enzyme. GAD immunocytochemistry stained many neurons located mainly in the hilar region but also in the granular and molecular layers. Granule cells were not immunoreactive. On embryonic day (E) 14, [3H]thymidine injection labelled 12.8% of GAD-positive (+) neurons in sections of the area dentata processed at an age of 40 days postnatally. This proportion decreased to 1.8% on E17 and to 1% on E18. No GAD (+) neurons were labelled by thymidine injection on E19, while non-immunoreactive granule cells and CA4 pyramids were still labelled, indicating persisting neurogenesis of those cells.

Commissural afferents innervate glutamate decarboxylase immunoreactive non-pyramidal neurons in the guinea pig hippocampus.

The innervation of GABAergic hippocampal neurons by commissural fibers was investigated in the guinea pig by a combined anterograde degeneration - immunocytochemical technique. Presumed GABAergic neurons were identified by immunocytochemistry for glutamate decarboxylase (GAD) and the commissural fibers by electron-dense degeneration following contralateral transection of the fimbria. Commissural afferents were found to establish asymmetric synaptic contacts with non-pyramidal GAD-immunoreactive neurons located in subpyramidal and suprapyramidal zones of region CA1. The observed connection suggests that inhibition of pyramidal cells may occur in a feed-forward manner as postulated by electrophysiological studies.

A comparative study of four sublines of mouse fibroblast cells.

Cell doubling time, DNA distribution pattern, frequency distribution of chromosome numbers per cell and degree of synchrony obtained after mitotic selection were studied in 4 different sublines of mouse fibroblast cells, NCTC L-929, in culture. The 4 sublines did not differ with respect to their cell kinetic data but showed changes of the chromosome pattern compared to the stemline and compared to each other suggesting that chromosome analysis provides a very sensitive means to detect evolutianary changes of a permanent cell line.