Morphological Differences Among Eyeless Amphipods in the Genus Stygobromus Dwelling in Different Subterranean Habitats

The amphipod genus Stygobromus occurs in a variety of subterranean habitats in North America, including caves, phreatic (groundwater) lakes, and superficial subterranean habitats (seeps and epikarst). The habitats share the absence of light but differ in other features, such as pore size of the habitat, available food, and degree of seasonality. Measurements of body size, antennal size, and antennal segment number of type specimens were compared for 56 species occurring in the eastern United States. Except for differences in body size, differences among species in the four different habitats were not significant. Body size was related to relative pore size of the habitat, e.g., epikarst, with the smallest spaces, had the smallest species. However, in all habitats, there was one very large species (\u3e 15mm); these enigmatic species apparently occupy a distinct ecological niche, perhaps being more predatory. Differences in relative antennal size showed no significant differences among habitats, and differences in number of antennal segments were marginally significant (P = 0.06) among habitat types and not in the predicted pattern. Differences among habitats in seasonality and available food seemed to be a minor part of the selective environment; absence of light seemed to be a major part of the selective environment

Genomic analyses in Cornelia de Lange Syndrome and related diagnoses: Novel candidate genes, <scp>genotype–phenotype</scp> correlations and common mechanisms

Cornelia de Lange Syndrome (CdLS) is a rare, dominantly inherited multisystem developmental disorder characterized by highly variable manifestations of growth and developmental delays, upper limb involvement, hypertrichosis, cardiac, gastrointestinal, craniofacial, and other systemic features. Pathogenic variants in genes encoding cohesin complex structural subunits and regulatory proteins (NIPBL, SMC1A, SMC3, HDAC8, and RAD21) are the major pathogenic contributors to CdLS. Heterozygous or hemizygous variants in the genes encoding these five proteins have been found to be contributory to CdLS, with variants in NIPBL accounting for the majority (&gt;60%) of cases, and the only gene identified to date that results in the severe or classic form of CdLS when mutated. Pathogenic variants in cohesin genes other than NIPBL tend to result in a less severe phenotype. Causative variants in additional genes, such as ANKRD11, EP300, AFF4, TAF1, and BRD4, can cause a CdLS‐like phenotype. The common role that these genes, and others, play as critical regulators of developmental transcriptional control has led to the conditions they cause being referred to as disorders of transcriptional regulation (or “DTRs”). Here, we report the results of a comprehensive molecular analysis in a cohort of 716 probands with typical and atypical CdLS in order to delineate the genetic contribution of causative variants in cohesin complex genes as well as novel candidate genes, genotype–phenotype correlations, and the utility of genome sequencing in understanding the mutational landscape in this population

What's the temperature in tropical caves?

Hourly temperature was measured for approximately one year at 17 stations in three caves in Quintana Roo, Mexico. Thirteen of these stations were in the extensive twilight zones of all three caves. All seventeen stations showed seasonality in temperature with a 3°C drop during the Nortes season. Two of the caves, Muévelo Sabrosito and Muévelo Rico, showed greater variability during the winter months while in Río Secreto (Tuch) variability was greatest during the rainy season. Río Secreto is less open to the surface than the other two. All sites also showed a daily temperature cycle, although it was very faint in some Río Secreto (Tuch) sites. While temperature variability is diminished relative to surface variation, its temporal pattern is worthy of further study

Combined type versus ADHD predominantly hyperactive-impulsive type: is there a difference in functional impairment?

OBJECTIVE: The purpose of this study was to evaluate whether preschool children with attention-deficit/hyperactivity disorder predominantly hyperactive-impulsive type (ADHD-HI) and ADHD combined type (ADHD-C) have different levels of functional impairment in four domains: externalizing (oppositional and disruptive) behaviors, internalizing (anxious) behaviors, social skills, and preacademic functioning. METHODS: The subjects were 102 children 3 to 5 years of age, meeting DSM-IV criteria for ADHD. Children with ADHD-C versus ADHD-HI were compared across at least two measures for each of the four functional domains. Oppositional and anxious behaviors were assessed on the Conners Parent and Teacher Rating Scales. In addition, off-task and disruptive behaviors were assessed by direct observation in the preschool setting. Social skills were assessed on the parent and teacher versions of the Social Skills Rating System and preacademic skills were assessed on the letter word identification, passage comprehension, and applied problems subtests of the Woodcock-Johnson III Tests of Achievement and the initial sound fluency subtest of the Dynamic Indicators of Basic Early Literacy Skills 5th Edition. RESULTS: There were no significant differences between the groups on rating scale T scores for parent-reported oppositional symptoms (ADHD-C vs ADHD-HI; 66.7 +/- 13.5 vs 65.7 +/- 11.7; p = .73); parent-reported anxious symptoms (53.5 +/- 11.1 vs 53.2 +/- 9.7; p = .90); teacher-reported oppositional symptoms (70.9 +/- 15.6 vs 75.5 +/- 14.7; p = .17); or teacher reported anxious symptoms (59.2 +/- 11.6 vs 58.5 +/- 12.2; p = .77). No statistically significant differences were found between the groups when examining off-task and/or disruptive behavior during structured and free play observations at school. No significant differences between the subtypes were found for social skills or preacademic functioning. CONCLUSIONS: Across the four areas of functioning assessed in this study, preschool children with ADHD-HI and those with ADHD-C demonstrated similar levels of functioning. This study, in combination with data from longitudinal studies demonstrating that most children with ADHD-HI are later diagnosed with ADHD-C, suggests that ADHD-HI may represent an earlier form of ADHD-C as opposed to a distinct subtype

Body composition estimation using skinfolds in children with and without health conditions affecting growth and body composition.

Background: Body composition prediction equations using skinfolds are useful alternatives to advanced techniques, but their utility across diverse paediatric populations is unknown. Aim: To evaluate published and new prediction equations across diverse samples of children with health conditions affecting growth and body composition. Subjects and methods: Anthropometric and dual-energy X-ray absorptiometry (DXA) body composition measures were obtained in children with Down syndrome (n = 59), Crohn disease (n = 128), steroid-sensitive nephrotic syndrome (n = 67) and a healthy reference group (n = 835). Published body composition equations were evaluated. New equations were developed for ages 3–21 years using the healthy reference sample and validated in other groups and national survey data. Results: Fat mass (FM), fat-free mass (FFM) and percentage body fat (%BF) from published equations were highly correlated with DXA-derived measures (r = 0.71–0.98), but with poor agreement (mean difference = 2.4 kg, −1.9 kg and 6.3% for FM, FFM and %BF). New equations produced similar correlations (r = 0.85–1.0) with improved agreement for the reference group (0.2 kg, 0.4 kg and 0.0% for FM, FFM and %BF, respectively) and in sub-groups. Conclusions: New body composition prediction equations show excellent agreement with DXA and improve body composition estimation in healthy children and those with selected conditions affecting growth