Narrative language competence in children and adolescents with Down syndrome

This study was designed to examine the narrative language abilities of children and adolescents with Down syndrome in comparison to same-age peers with fragile X syndrome and younger typically developing children matched by nonverbal cognitive ability levels. Participants produced narrative retells from a wordless picture book. Narratives were analyzed at the macrostructural (i.e., their internal episodic structure) and the microstructural (i.e., rate of use of specific word categories) levels. Mean length of utterance, a microstructural metric of syntactic complexity, was used as a control variable. Participants with Down syndrome produced fewer episodic elements in their narratives (i.e., their narratives were less fully realized) than the typically developing participants, although mean length of utterance differences accounted for the macrostructural differences between participant groups. At the microstructural level, participants with Down syndrome displayed a lower rate of verb use than the groups with fragile X syndrome and typical development, even after accounting for mean length of utterance. These findings reflect both similarities and differences between individuals with Down syndrome or fragile X syndrome and contribute to our understanding of the language phenotype of Down syndrome. Implications for interventions to promote language development and academic achievement are discussed

Parasite Component Community of Smalltooth Sawfish Off Florida: Diversity, Conservation Concerns, and Research Applications

Compared with that of other charismatic elasmobranchs, the component community of metazoan parasites infecting endangered smalltooth sawfish Pristis pectinata is exceedingly poorly characterized: adults of Dermophthirioides pristidis and Neoheterocotyle inpristi (ectoparasitic flatworms of skin and gill, respectively) were the only confirmed parasites prior to the description, based on specimens reported herein, of Mycteronastes caalusi. Our opportune and directed parasitological examinations of 290 smalltooth sawfish (277 live inspections; 13 necropsies; 671 to 2640 mm stretch total length) in south Florida coastal waters revealed at least 8 species of Platyhelminthes, 9 of Arthropoda, 4 of Annelida, and 1 of Nematoda. This collection includes representatives of an undescribed species of Aporocotylidae (Digenea) and myriad new host records, considerably updating and advancing our understanding of smalltooth sawfish symbionts. We also confirm that D. pristidis and N. inpristi are extant and propose D. pristidis as a reliable biological tag. Some of these parasites are evidently highly host-specific and so vulnerable to extinction

Increased Inter-Colony Fusion Rates Are Associated with Reduced COI Haplotype Diversity in an Invasive Colonial Ascidian Didemnum vexillum

Considerable progress in our understanding of the population genetic changes associated with biological invasions has been made over the past decade. Using selectively neutral loci, it has been established that reductions in genetic diversity, reflecting founder effects, have occurred during the establishment of some invasive populations. However, some colonial organisms may actually gain an ecological advantage from reduced genetic diversity because of the associated reduction in inter-colony conflict. Here we report population genetic analyses, along with colony fusion experiments, for a highly invasive colonial ascidian, Didemnum vexillum. Analyses based on mitochondrial cytochrome oxidase I (COI) partial coding sequences revealed two distinct D. vexillum clades. One COI clade appears to be restricted to the probable native region (i.e., north-west Pacific Ocean), while the other clade is present in widely dispersed temperate coastal waters around the world. This clade structure was supported by 18S ribosomal DNA (rDNA) sequence data, which revealed a one base-pair difference between the two clades. Recently established populations of D. vexillum in New Zealand displayed greatly reduced COI genetic diversity when compared with D. vexillum in Japan. In association with this reduction in genetic diversity was a significantly higher inter-colony fusion rate between randomly paired New Zealand D. vexillum colonies (80%, standard deviation ±18%) when compared with colonies found in Japan (27%, standard deviation ±15%). The results of this study add to growing evidence that for colonial organisms reductions in population level genetic diversity may alter colony interaction dynamics and enhance the invasive potential of newly colonizing species

Patterns and predictors of adaptive skills in 2- to 7-year-old children with Down syndrome.

BackgroundThere is substantial variability in adaptive skills among individuals with Down syndrome. Few studies, however, have focused on the early developmental period or on the potential sources of variability in adaptive skills. This study characterizes adaptive skills in young children with Down syndrome and investigates child characteristics associated with adaptive skills.MethodsParticipants were 44 children with Down syndrome ranging in age from 2.50 to 7.99 years (M = 4.66 years, SD = 1.46). The Vineland Adaptive Behavior Scales-3 (VABS-3) Comprehensive Interview Form was used to assess adaptive behavior in the three core domains: socialization, daily living, and communication skills. Caregivers also reported on motor skills and autism spectrum disorder symptoms. Child cognitive abilities were assessed.ResultsAnalyses comparing mean standard score performance across the three VABS-3 core domains demonstrated significant differences between all pairs of domains, resulting in a group-level pattern of socialization > daily living > communication skills. At the individual level, 10 different patterns of relative strength and weakness were identified, with only 18% of participants evidencing significant differences between adaptive skill domain standard scores corresponding to the group-level pattern of significant differences. Child characteristics (cognitive abilities, motor skills, and autism spectrum disorder symptoms) were significantly associated with VABS-3 adaptive domain standard scores.ConclusionThese findings underscore the importance of individualizing intervention programs focused on improving the adaptive skills of young children with Down syndrome based on consideration of the child's relative adaptive strengths and weaknesses

Preventing Hepatitis B Reactivation During Anti‐CD20 Antibody Treatment in the Veterans Health Administration

Hepatitis B virus (HBV) reactivation may occur with high risk immunosuppression, such as anti‐cluster of differentiation (CD)20 antibodies (Abs). Appropriate HBV prophylaxis during anti‐CD20 Ab therapy averts hepatitis, chemotherapy disruption, and death. Serologic evidence of prior HBV exposure is present in one in nine veterans in the Veterans Health Administration (VHA). In 2014, most (61%‐73%) patients in the VHA who were receiving anti‐CD20 Ab treatment underwent HBV testing, yet 90% and antiviral prophylaxis to >80%

Defining Expressive Language Benchmarks for Children with Down Syndrome

Establishing expressive language benchmarks (ELBs) for children with Down syndrome (DS), as developed by Tager-Flusberg et al. for children with autism, is critically needed to inform the development of novel treatments, identify individualized treatment targets, and promote accurate monitoring of progress. In the present study, we assessed ELB assignments in three language domains (phonology, vocabulary, and grammar) for 53 young children with DS (CA range: 2.50–7.99 years) using standardized assessments. The participants were classified into one of four ELB levels (preverbal, first words, word combinations, and sentences) in each language domain. Associations with additional measures of language, chronological age, nonverbal cognition, and verbal short-term memory were considered. Analyses of individual ELB profiles indicated substantial variability across the three language domains, with six different patterns of variation across domains emerging. At the same time, the ELB categories were significantly associated with independent language measures and broader developmental domains. Moreover, ELB changes were observed in a small sample of children with DS reassessed 18–24 months after the initial visit. Results from the present study suggest the procedures outlined by Tager-Flusberg et al. for defining ELBs are a potentially useful tool for describing the language abilities of children with DS

Defining Expressive Language Benchmarks for Children with Down Syndrome.

Establishing expressive language benchmarks (ELBs) for children with Down syndrome (DS), as developed by Tager-Flusberg et al. for children with autism, is critically needed to inform the development of novel treatments, identify individualized treatment targets, and promote accurate monitoring of progress. In the present study, we assessed ELB assignments in three language domains (phonology, vocabulary, and grammar) for 53 young children with DS (CA range: 2.50-7.99 years) using standardized assessments. The participants were classified into one of four ELB levels (preverbal, first words, word combinations, and sentences) in each language domain. Associations with additional measures of language, chronological age, nonverbal cognition, and verbal short-term memory were considered. Analyses of individual ELB profiles indicated substantial variability across the three language domains, with six different patterns of variation across domains emerging. At the same time, the ELB categories were significantly associated with independent language measures and broader developmental domains. Moreover, ELB changes were observed in a small sample of children with DS reassessed 18-24 months after the initial visit. Results from the present study suggest the procedures outlined by Tager-Flusberg et al. for defining ELBs are a potentially useful tool for describing the language abilities of children with DS

Distance delivery of a spoken language intervention for school-aged and adolescent boys with fragile X syndrome

A small randomized group design (N = 20) was used to examine a parent-implemented intervention designed to improve the spoken language skills of school-aged and adolescent boys with FXS, the leading cause of inherited intellectual disability. The intervention was implemented by speech-language pathologists who used distance video-teleconferencing to deliver the intervention. The intervention taught mothers to use a set of language facilitation strategies while interacting with their children in the context of shared story-telling. Treatment group mothers significantly improved their use of the targeted intervention strategies. Children in the treatment group increased the duration of engagement in the shared story-telling activity as well as use of utterances that maintained the topic of the story. Children also showed increases in lexical diversity, but not in grammatical complexity