Developmental Coordination Disorder before the Age of Three: A Longitudinal Retrospective Study in a Belgian Center for Developmental Disabilities.

This study aimed to explore the association between developmental coordination disorder (DCD) diagnosed after the age of three and both a standardized motor test­the Alberta Infant Motor Scale (AIMS)­and non-standardized observation of movement quality carried out before the age of three. Children at risk or with developmental concerns were studied retrospectively. Children were excluded in case of a diagnosis, excluding DCD, e.g., cerebral palsy, or IQ < 70. Of the 503 included children, 246 were diagnosed with (at-risk) DCD. Multivariate binary logistic regression revealed a significant association between DCD diagnosis after the age of three and male gender and with different aspects of poor movement quality in different age groups before the age three. Univariate analyses revealed an association between DCD diagnosis and the number of poor movement-quality descriptions at 0−6 months, 6−12 months, and 18 months−3 years but not with the AIMS scores. The MABC-2 scores after the age of three were significantly correlated with the number of poor movement-quality descriptions in age groups 0−6 months and 18 months−3 years and with the AIMS scores in age groups 6−12 months and 12−18 months. The results suggest that DCD can be associated with poor movement quality before the age of three.

Chemoenzymatic Approach toward the Synthesis of 3-O-(α/ß)-Glucosylated 3-Hydroxy-ß-lactams.

Glycosylation significantly alters the biological and physicochemical properties of small molecules. ß-Lactam alcohols comprise eligible substrates for such a transformation based on their distinct relevance in the chemical and medicinal community. In this framework, the unprecedented enzymatic glycosylation of the rigid and highly strained four-membered ß-lactam azaheterocycle was studied. For this purpose, cis-3-hydroxy-ß-lactams were efficiently prepared in three steps by means of a classical organic synthesis approach, while a biocatalytic step was implemented for the selective formation of the corresponding 3-O-α- and -ß-glucosides, hence overcoming the complexities typically encountered in synthetic glycochemistry and contributing to the increasing demand for sustainable processes in the framework of green chemistry. Two carbohydrate-active enzymes were selected based on their broad acceptor specificity and subsequently applied for the α- or ß-selective formation of ß-lactam-sugar adducts, using sucrose as a glucosyl donor.

Effectiveness of a self-regulated remedial program for handwriting difficulties.

BACKGROUND: Handwriting difficulties may have pervasive effects on a child's school performance. I Can! is a remedial handwriting program with a focus on self-regulated learning and applying motor learning principles combined with a behavioural approach. It is developed for typically developing children with handwriting problems. OBJECTIVE: The study aim was to evaluate the program's effectiveness. MATERIALS AND METHODS: Thirty-one children aged 7-8 year participated in a cross-over study. Handwriting quality and speed were repeatedly assessed by means of the Systematic Screening of Handwriting Difficulties test. Difficulties addressed were fluency in letter formation, fluency in letter connections, letter height, regularity of letter height, space between words, and line path. RESULTS: Mixed model analysis revealed improved quality of writing and speed for all children but significantly more improvement in handwriting quality for the children participating in the program. Although writing speed improved over time, no additional effects of the program occurred. CONCLUSIONS AND SIGNIFICANCE: 'I Can!' is found to be an effective instructive program to ameliorate handwriting quality in typically developing children with handwriting difficulties. The program's success was by a therapy burst of only 7 weeks focusing on the child's self-regulated learning capacities, within an individualized education plan according to their needs and goals.

Sequence determinants of nucleotide binding in Sucrose Synthase: improving the affinity of a bacterial Sucrose Synthase for UDP by introducing plant residues.

Sucrose Synthase (SuSy) catalyzes the reversible conversion of sucrose and a nucleoside diphosphate (NDP) into NDP-glucose and fructose. Biochemical characterization of several plant and bacterial SuSys has revealed that the eukaryotic enzymes preferentially use UDP whereas prokaryotic SuSys prefer ADP as acceptor. In this study, SuSy from the bacterium Acidithiobacillus caldus, which has a higher affinity for ADP as reflected by the 25-fold lower Km value compared to UDP, was used as a test case to scrutinize the effect of introducing plant residues at positions in a putative nucleotide binding motif surrounding the nucleobase ring of NDP. All eight single to sextuple mutants had similar activities as the wild-type enzyme but significantly reduced Km values for UDP (up to 60 times). In addition, we recognized that substrate inhibition by UDP is introduced by a methionine at position 637. The affinity for ADP also increased for all but one variant, although the improvement was much smaller compared to UDP. Further characterization of a double mutant also revealed more than 2-fold reduction in Km values for CDP and GDP. This demonstrates the general impact of the motif on nucleotide binding. Furthermore, this research also led to the establishment of a bacterial SuSy variant that is suitable for the recycling of UDP during glycosylation reactions. The latter was successfully demonstrated by combining this variant with a glycosyltransferase in a one-pot reaction for the production of the C-glucoside nothofagin, a health-promoting flavonoid naturally found in rooibos (tea).

Screening of recombinant glycosyltransferases reveals the broad acceptor specificity of stevia UGT-76G1.

UDP-glycosyltransferases (UGTs) are a promising class of biocatalysts that offer a sustainable alternative for chemical glycosylation of natural products. In this study, we aimed to characterize plant-derived UGTs from the GT-1 family with an emphasis on their acceptor promiscuity and their potential application in glycosylation processes. Recombinant expression in E. coli provided sufficient amounts of enzyme for the in-depth characterization of the salicylic acid UGT from Capsella rubella (UGT-SACr) and the stevia UGT from Stevia rebaudiana (UGT-76G1Sr). The latter was found to have a remarkably broad specificity with activities on a wide diversity of structures, from aliphatic and branched alcohols, over small phenolics to larger flavonoids, terpenoids and even higher glycoside compounds. As an example for its industrial potential, the glycosylation of curcumin was thoroughly evaluated. Under optimized conditions, 96% of curcumin was converted within 24h into the corresponding curcumin ß-glycosides. In addition, the reaction was performed in a coupled system with sucrose synthase from Glycine max, to enable the cost-efficient (re)generation of UDP-Glc from sucrose as abundant and renewable resource.

Enzymatic Glycosylation of Phenolic Antioxidants: Phosphorylase-Mediated Synthesis and Characterization.

Although numerous biologically active molecules exist as glycosides in nature, information on the activity, stability, and solubility of glycosylated antioxidants is rather limited to date. In this work, a wide variety of antioxidants were glycosylated using different phosphorylase enzymes. The resulting antioxidant library, containing α/ß-glucosides, different regioisomers, cellobiosides, and cellotriosides, was then characterized. Glycosylation was found to significantly increase the solubility and stability of all evaluated compounds. Despite decreased radical-scavenging abilities, most glycosides were identified to be potent antioxidants, outperforming the commonly used 2,6-bis(1,1-dimethylethyl)-4-methylphenol (BHT). Moreover, the point of attachment, the anomeric configuration, and the glycosidic chain length were found to influence the properties of these phenolic glycosides.

Neonatal and neurodevelopmental outcome of children aged 3-10 years born following assisted oocyte activation.

Assisted oocyte activation (AOA) using a calcium ionophore has been used for more than a decade following intracytoplasmic sperm injection (ICSI) fertilization failure. However, since AOA does not mimic precisely the physiological fertilization process, concerns exist about its use in human assisted reproduction. This study assessed the neonatal and neurodevelopmental outcome of children aged ≥ 3 years who had been born following AOA in our centre. Twenty-one children participated in the study (81% response rate; mean age 63.6 ± 21.07 months). Neonatal data were collected via questionnaires. Neurodevelopmental outcome was tested using the Reynell Developmental Language Scales or Clinical Evaluation of Language Fundamentals, Wechsler Preschool and Primary Scale of Intelligence or Wechsler Intelligence Scale for Children, and the Movement Assessment Battery for Children III. Behaviour was scored by the Social Communication Questionnaire, the Child Behaviour Checklist and the Teachers Report Form. For all tests and questionnaires, the mean outcomes lay within the expected ranges. These are first data on the developmental outcome of AOA children. The high response rate and the robustness of the tests support the data, which are reassuring although still considered preliminary. Therefore, AOA should still be performed only in selected couples.

Stability of motor problems in young children with or at risk of autism spectrum disorders, ADHD, and or developmental coordination disorder.

AIM: The aim of this study was to investigate the stability of motor problems in a clinically referred sample of children with, or at risk of, autism spectrum disorders (ASDs), attention-deficit-hyperactivity disorder (ADHD), and/or developmental coordination disorder (DCD). METHOD: Participants were 49 children (39 males, 10 females; mean age 5y 6 mo, SD 10 mo) with various developmental problems, a Movement Assessment Battery for Children (M-ABC) score on or below the 15th centile, and an IQ of 70 or more. Sixteen children were at risk of developing ADHD, 15 children had a diagnosis of, or were at risk of developing ASD, and 18 children had neither diagnosis. Children were reassessed 2 to 3 years later. RESULTS: At follow-up (mean age 7y 11 mo; SD 1y), the mean M-ABC score was significantly increased, and in 22 children was no longer below the 15th centile. A general linear model to compare the difference in M-ABC scores in the three groups of children demonstrated a significant difference between groups (p=0.013), with the age at the initial assessment as a significant covariate (p=0.052). The group of children with or at risk of ASD showed less improvement in motor performance. INTERPRETATION: Motor problems among preschool age children are not always stable, but appear to be so in most children with ASDs.

Sensory contributions to balance in boys with developmental coordination disorder.

This study examined and compared the control of posture during bilateral stance in ten boys with Developmental Coordination Disorder (DCD) of 6-8 years old and ten matched typically developing boys in four sensory conditions (with or without vision, on a firm or complaint surface). In all conditions mean postural sway velocity was larger for the boys with DCD, in spite of a normal score on the balance items of the Movement Assessment Battery for Children. A Group X Condition interaction revealed a larger dependency on vision in the boys with DCD when standing on a firm surface. These results suggest that in this specific subgroup of boys with DCD with predominantly problems in fine motor and ball skills postural control problems may still be prevalent and may possibly be associated with difficulties to re-weight sensory information in response to environmental demands.

Differences in gait between children with and without developmental coordination disorder.

In the present study the walking pattern of 10 children with developmental coordination disorder (DCD) was investigated and compared to that of 10 typically developing, matched control children. All children walked at a similar velocity that was scaled to the length of the leg on a motor-driven treadmill. Three-dimensional kinematics were recorded with a motion capture digital camera system. The spatiotemporal parameters of the gait pattern revealed that children with DCD walked with shorter steps and at a higher frequency than the typically developing children. In addition, the children with DCD exhibited a body configuration that demonstrated increased trunk inclination during the entire gait cycle and enhanced during the entire gait cycle. At toe-off a less pronounced plantar flexion of the ankle was observed in children with DCD. In conclusion, it appeared that children with DCD make adaptations to their gait pattern on a treadmill to compensate for problems with neuromuscular and/or balance control. These adaptations seem to result in a safer walking strategy where the compromise between equilibrium and propulsion is different compared to typically developing children.