Concordance of the Adaptive Behavior Assessment System, second and third editions.

BACKGROUND: Adaptive functioning is an important area of assessment with implications for differential diagnosis, educational placement, service eligibility and criminal sentencing. While periodic normative and content updates of adaptive functioning measures are necessary to keep measures relevant, knowledge of equivalence between versions is also required if adaptive measures are to be used to track the stability of adaptive functioning skills over time. METHOD: This paper presents two studies that used between-group and within-group comparison designs to examine the equivalence of the second and third editions of the Adaptive Behavior Assessment System (ABAS) in a mixed clinical sample. In study 1, ABAS-2 scores for children assessed between 2014 and 2015 (n = 1036; mean age = 10.24, SD = 3.44) were compared with ABAS-3 scores for children assessed between 2015 and 2016 (n = 1291; mean age = 10.51, SD = 3.70). Study 2 examined a separate sample of clinically referred children (n = 572) for whom parent ratings had been obtained on both the ABAS-2 (mean age = 9.65, SD = 2.80) and ABAS-3 (mean age = 13.33, SD = 2.95) in the course of repeated assessment. RESULTS: For Study 1, while no intelligence quotient score differences were observed between the ABAS-2 group (mean Verbal Comprehension Index = 93.67, SD = 16.95) and the ABAS-3 group (mean Verbal Comprehension Index = 93.08, SD = 17.42), ABAS-2 scores were lower than ABAS-3 scores on the Conceptual, Practical, and General Adaptive Composite scales. In study 2, a similar pattern was observed (ABAS-2 < ABAS-3 on the Conceptual, Practical, and General Adaptive Composite scales), and concordance correlation coefficients ranged from 0.54 [0.49, 0.58] (Practical composite) to 0.68 [0.64, 0.72] (Conceptual composite). The Practical composite had the lowest concordance correlation coefficient value and the largest mean score difference between ABAS versions. CONCLUSIONS: The ABAS-3 scores may be higher than ABAS-2 scores in clinical populations. Knowledge of these potential discrepancies will be critical when interpreting standard score changes across ABAS versions in the course of clinical, educational and forensic assessments.

Executive functions among youth with Down Syndrome and co-existing neurobehavioural disorders.

BACKGROUND: Executive function (EF) deficits are a recognised component of the cognitive phenotype of youth with Down Syndrome (DS). Recent research in this area emphasises the use of behaviour ratings, such as the Behavior Rating Inventory of Executive Functions-Preschool Version (BRIEF-P), to capture the real-world applications of executive functions. To account for the intellectual functioning of youth with DS, this measure is used out of age range; however, its psychometric properties when used in this fashion are unknown. The goals of this study are to evaluate psychometric characteristics of the BRIEF-P among youth with DS and to examine the pattern of EF strengths/weaknesses in children with DS and co-occurring psychiatric conditions. METHOD: A total of 188 clinically referred youth with DS, ages 3-13 were rated by their caregivers using the BRIEF-P. These youth were evaluated by a clinician with expertise in DS and were characterised as having no co-occurring behavioural disorder (Typical DS group), co-occurring Autism Spectrum Disorder (DS + ASD) or co-occurring Disruptive Behaviour Disorder (DS + DBD). RESULTS: An exploratory factor analysis of item-level BRIEF-P data from clinically referred youth with DS supported the theoretically derived three-factor structure originally proposed for the BRIEF-P (Emergent Metacognition, Flexibility and Inhibitory Self-Control); however, the item composition of each factor varied somewhat in comparison to the original structure of the measure. Group comparisons indicate that, while youth with typical DS evidence fewer executive function difficulties across all domains, youth with DS + ASD show the greatest weaknesses in Emergent Metacognition, and youth with DS + DBD show significant difficulties in both Emergent Metacognition and Inhibition. CONCLUSIONS: These findings offer preliminary support for use of the BRIEF-P with clinically referred youth with Down Syndrome. Some scoring modifications may be necessary if the theoretically derived index scores are to be used with this population. BRIEF-P scores may offer an empirical basis for differentiating DS youth with varying behavioural profiles.

If Opportunity Knocks: Understanding Contextual Factors' Influence on Cognitive Systems.

Central to the Research Domain Criteria (RDoC) framework is the idea that RDoC constructs, which vary dimensionally by individual, are heavily influenced by contextual factors. Perhaps chief among these contextual factors is structural opportunity - the quality of resources available to a child as they grow. The aim of this study is to understand the impact of access to opportunity during childhood on three central RDoC cognitive systems constructs: language, visual perception, and attention. These constructs were measured using clinical data from psychological evaluations of youth ages 4-18 years (N = 16,523; Mage = 10.57, 62.3% male, 55.3% White). Structural opportunity was measured using the geocoded Child Opportunity Index 2.0 (COI), a composite score reflecting 29 weighted indicators of access to the types of neighborhood conditions that help children thrive. Findings indicate that, controlling for demographic and socioeconomic factors, greater access to opportunity is associated with significantly stronger cognitive skills across all three constructs. However, opportunity uniquely explains the largest proportion of the variance in language skills (8.4%), compared to 5.8% of the variance in visual processing skills and less than 2% of the variance in attention. Further, a moderating effect of age was found on the relation between COI and language skills, suggesting that the longer children remain exposed to lower levels of opportunity, the lower their language skills tend to be. Understanding how opportunity impacts cognitive development allows clinicians to offer better tailored recommendations to support children with cognitive systems deficits, and will support policy recommendations around access to opportunity.

Pre-appointment online assessment of patient complexity: Towards a personalized model of neuropsychological assessment.

Recent events such as the global pandemic of COVID-19 have challenged neuropsychologists to scale up their capacity to conduct portions of their assessment remotely. While more complex patients will likely continue to require on-site, office-based interaction and assessment, the current emergency-based expansion of online and telehealth evaluation practices may ultimately lay the groundwork for more routine, online assessment of patients with less complex presentations in the future. To this end, the current study evaluated a pre-appointment, online methodology for differentiating referred pediatric patients based upon the scope and severity of their caregiver-reported adaptive, academic, attentional, behavioral, and emotional impairment. Prior to on-site assessment, parents/caregivers of 2197 children (Mean age = 10.0y, range = 4-19y, 62% male) completed an online developmental history form screening for symptoms of adaptive, attentional, learning, affective, and behavioral impairment; 71% of those children eventually underwent assessment. Using latent class analysis, the data supported a reproducible 4-class model consisting of groups of children at increased risk for: 1) severe multi-domain dysfunction; the "High Complexity" group, 30%, 2) behavioral-affective (but not academic) dysregulation; the "Behavioral Focus" group, 13%, 3) academic (but not behavioral-affective) problems; the "Academic and Inattention" group, 37%, and 4) patients with minimal clinical complexity; the "Low Complexity" group, 20%. Comparison of pre-visit classification with day-of-assessment standardized test scores supported the validity of patient subtypes. Moving forward, pre-appointment clarification of patient complexity may support efficient patient triage with regard to assessment modality (e.g., on-site or online) and length of appointment (e.g., comprehensive or targeted).

Caregiver Perspectives on Informed Consent for a Pediatric Learning Healthcare System Model of Care.

BACKGROUND: Data is needed to provide insight into the issue of preference around consent for use of pediatric clinical data for research. This study evaluated caregivers' preferences concerning use of their child's clinical information. METHODS: Caregivers of children (n = 101; response rate 81.5% of n = 124) presenting for psychological evaluation at an urban medical center viewed a video regarding how the information contained in their child's medical record could be used for research. RESULTS: An anonymous survey following the video indicated that: 1) >90% of caregivers felt comfortable with their child's information being used; 2) >90% of caregivers felt their child's privacy would be adequately protected; 3) 98% of caregivers reported themselves to be as or more likely to return to the institution after viewing the video; 4) 60% of caregivers felt no additional consent procedures beyond viewing the video were needed, while 20% preferred an opt-out and 20% preferred a traditional consent procedure. Caregiver demographic variables were largely unrelated to consent preferences. DISCUSSION: Overall, caregivers reported strong support for use of their child's clinical data for research purposes.

Identification of the acidic residues in the active site of DNA polymerase III.

The mechanism of nucleotide addition by DNA polymerases involves two metal ions that are coordinated in the active site by conserved acidic residues. The three acidic residues that chelate Mg2+ in the active site of Escherichia coli DNA polymerase III have been identified as Asp401, Asp403, and Asp555 by site-directed mutagenesis. Candidates for mutagenesis were initially chosen based on absolute conservation of acidic residues in an alignment of more than 20 diverse DnaE sequences. Conservative Asp to Glu mutations at positions 401 and 403 reduced the activities of the mutant polymerases 2000 and 333-fold, respectively, from that of the wild-type. The third carboxylate was identified by a series of mutations for each critical candidate. With the exception of Glu, all of the mutations at Asp555 led to severely diminished polymerase activity, while each of the other candidates exhibited several relatively active mutant polymerases. Moreover, only the identified active site mutant polymerases displayed a significant enhancement of activity in Mn2+ compared with Mg2+. These data suggest a direct involvement of the mutated amino acid in metal ion binding.

Inter-species sequence diversity in the replication initiation region of Paramecium mitochondrial DNA.

Mitochondrial DNA from Paramecium aurelia is a linear molecule. Replication is initiated at a unique cross-linked molecular terminus. During replication dimer length molecules, consisting of two head-to-head monomers, are generated. We have cloned the head-to-head dimer initiation region from five different species and several stocks (or races) within species and determined its DNA sequence. For all species, this dimer initiation region consists of a central non-palindromic sequence containing almost exclusively A and T, arranged in an array of direct tandem repeats. In an intra-species comparison, the sequences of the repeat units are relatively homogeneous; inter-species comparisons, however, show diversity except for a conserved "Goldberg-Hogness box", T-A-T-A-A-A-T-A. The size of a repeat unit and the number of repeats within a molecule can vary over a wide range, even in an intra-species comparison. Because of these wide inter-species variations observed, it is likely that the function of this region imposes few constraints on the sequence other than its high A + T content and possibly a Goldberg-Hogness box. The array of direct tandem repeats may have arisen from unequal recombination or crossover within this region. Adjacent to the non-palindromic region is a transcribed sequence which is highly conserved for all species and presumably represents a gene coding region.

Cloning and characterization of Paramecium mitochondrial DNA replication initiation regions.

Fragments containing the replication-initiation region of mitochondrial (mt) DNA from four species of Paramecium aurelia were ligated to the pBR322 plasmid and used to transform Escherichia coli. The criteria for identifying the desired mitochondrial DNA restriction fragments were based on the palindromic dimer structure of the replicative intermediate of this DNA. The nature of the cloned sequences was verified by hybridization to mitochondrial DNA fragments containing the initiation region, by determining the size of snapback renaturation products, and by determining the symmetry of restriction-endonuclease sites within the clones. Heterologous hybridization experiments showed that one species' initiation region is not homologous to the other three. Cleavage patterns of each of the clones by 18 different restriction enzymes were determined. There are no sites within approx. 250 bp of the center of the insert of any clone although there are numerous cleavages in more distal regions. These sites are generally symmetric about the center of the insert as expected for a palindromic structure. The characteristics of the cloned sequences support a proposed replication model for all four species studied.

Paramecium mitochondrial DNA sequences and RNA transcripts for cytochrome oxidase subunit I, URF1, and three ORFs adjacent to the replication origin.

A 2-kb region adjacent to the replication origin (ori) and a 3-kb region located between the small and large ribosomal RNAs of Paramecium mitochondrial (mt) DNA have been sequenced and the locations of their transcripts determined. The ori segment contains four transcripts, some of which are overlapping, which encode a known protein and two other open reading frames. The other segment encodes, on separate transcripts, the cytochrome c oxidase subunit one gene (COI) and the URF1 gene (ND1) common to most mt genomes. All these genes have the same orientation and do not contain introns. The COI gene is the most divergent of those known and has an internal 108 amino acid 'insert' not found in COI genes from other organisms. With these data it is possible to define a probable Paramecium mt genetic code. With the exception that TGA codes for tryptophan and the use of different start codons, Paramecium mtDNA appears to follow the universal code. GTA possibly can be used as a start codon.

Identification of Paramecium mitochondrial proteins using antibodies raised against fused mitochondrial gene products.

Paramecium aurelia mitochondrial (mt) DNA fragments carrying the coding regions for two proteins, P1 (in the region adjacent to the origin of replication) and COII (subunit II of cytochrome oxidase), were used to study mt gene expression. The sequence for the portion of mtDNA containing P1 has already been described [Pritchard et al., Gene 44 (1986) 243-253]. The complete nucleotide sequence of the portion containing the COII gene is presented here. An 18.5-kDa protein was produced in maxicells when a fragment containing a major portion of the sequence coding for P1 was used. This fragment and a fragment carrying the COII gene were cloned into the expression vector pTRPLE', and antibodies were raised against the resulting fusion proteins in an Escherichia coli lysate. Western blots of Paramecium mt extracts identified two proteins, one 21 kDa (COII) and the other 23.5 kDa (P1). The size of the P1 protein is in agreement with the size of the open reading frame in that region of mitochondrial DNA. Based on extensive amino acid homology to the Paramecium gene and limited homology to COII genes from other organisms, the COII gene in another ciliate, Tetrahymena pyriformis, was identified just upstream of the small subunit rDNA in previously published sequences (Schnare et al., 1986). The size of the COII gene and the homology with the COII gene from Tetrahymena suggest that ATC, ATT, GTG and GTC could be used as translational initiators in Paramecium mitochondria.

An unusual region of Paramecium mitochondrial DNA containing chloroplast-like genes.

Based on DNA and amino acid comparisons with known genes and their products, a region of the Paramecium aurelia mitochondrial (mt) genome has been found to encode the following gene products: (1) photosystem II protein G (psbG); (2) a large open reading frame (ORF400) which is also found encoded in the chloroplast (cp) DNA of tobacco (as ORF393) and liverwort (as ORF392), and in the kinetoplast maxicircle DNA of Leishmania tarentolae (as ORFs 3 and 4); (3) ribosomal protein L2 (rpl2); (4) ribosomal protein S12 (rps12); (5) ribosomal protein S14 (rps14); and (6) NADH dehydrogenase subunit 2 (ndh2). All of these genes have been found in cp DNA, but the psbG gene has never been identified in a mt genome, and ribosomal protein genes have never been located in an animal or protozoan mitochondrion. The ndh2 gene has been found in both mitochondria and plastids. The Paramecium genes are among the most divergent of those sequenced to date. Two of the genes are encoded on the strand of DNA complementary to that encoding all other known Paramecium mt genes. No gene contains an identifiable intron. The rps12 and psbG genes are probably overlapping. It is not yet known whether these genes are transcribed or have functional gene products. The presence of these genes in the mt genome raises interesting questions concerning their evolutionary origin.

Phonophoretic delivery of 10% hydrocortisone through the epidermis of humans as determined by serum cortisol concentrations.

BACKGROUND AND PURPOSE: The purpose of this investigation was to determine whether application of hydrocortisone phonophoresis enhances transcutaneous delivery of topically applied hydrocortisone in humans, as determined by blood cortisol levels. SUBJECTS: The subjects were 16 men and women, between the ages of 18 and 33 years (X = 25, SD = 2.74), without symptoms of any ongoing inflammatory condition. METHODS: A gel coupling medium containing 10% hydrocortisone acetate was used. Ultrasound was delivered over a 50-cm2 area for 5 minutes at an intensity of 1.0 W/cm2 and a frequency of 1.0 MHz. Each subject received a control treatment (ultrasound alone) and an experimental treatment (hydrocortisone phonophoresis) on the volar aspect of the forearm 1 week apart. Blood was drawn, under both control and experimental conditions, from a cubital vein just proximal to the treatment site prior to each treatment and 0,5, and 15 minutes posttreatment. Serum cortisol concentrations were measured using a fluorescence polarization immunoassay. RESULTS: No rise in serum cortisol concentrations following hydrocortisone phonophoresis was detected. CONCLUSION AND DISCUSSION: These findings suggest that there was no penetration of hydrocortisone through the epidermis and into the underlying vasculature. Clinical implications regarding hydrocortisone levels within the subcutaneous tissues are discussed, and further research is suggested.

Specific cleavages inflicted by venom phosphodiesterase on superhelical phiX174 DNA.

A single strand specific endonuclease, venom phosphodiesterase, acting on superhelical phiX174 DNA, inflicts at least seven specific cleavages. Six of these were located to within approximately +/-40 base-pairs by mapping with restriction endonucleases. They are at 12%, 27.4%, 42.7%, 47.5%, 76.1%, and 82.5%. All of these sites lie within regions containing runs of 16 or more base-pairs, of which 12 or more are A and T. Other similarly (A + T)-rich regions in the genome are not cleaved by the enzyme. Increasing the superhelical density of the substrate did not alter the locations of the cleavage sites. There is no correlation between the locations of the cleavage sites and the three known major promoter sites. Only two of five postulated transcription termination sites are cleaved by phosphodiesterase even though all of these terminators contain (A + T)-rich regions. The area containing the origin of viral DNA replication, which includes an (A + T)-rich sequence, is not cleaved.

Possible insertion sequences in a mosaic genome organization upstream of the exotoxin A gene in Pseudomonas aeruginosa.

Nucleotide sequence and Southern hybridization data revealed a mosaic genome organization in a region that extends several thousand base pairs upstream of the exotoxin A (toxA) gene in Pseudomonas aeruginosa. An interstrain comparison of DNA in this region showed a pattern of alternating segments of homologous and nonhomologous sequences. Two nonhomologous elements, approximately 1 kilobase pair upstream of the gene in strains PA103 and Ps388, were characterized in more detail. The sequence elements, denoted IS-PA-1 and IS-PA-2 for the different strains, are about 1,000 and 785 base pairs long, respectively, and have 5-base-pair direct repeats at their boundaries, consistent with their being DNA insertion sequences. The distribution of these elements in 34 different strains was determined. IS-PA-1 was found in a single copy upstream of toxA in half of the strains and was found in two copies in four of the strains. Some strains contained neither element, and one strain carried both. The genome of another strain, WR5, which lacks toxA, was shown to contain a 350-base-pair region that was highly homologous to DNA sequences located just upstream of toxA in other strains. The WR5 genome lacked several kilobase pairs of DNA that was found both upstream and downstream of this homologous region in the other strains.

Nucleotide sequence and expression of a phosphate-regulated gene encoding a secreted hemolysin of Pseudomonas aeruginosa.

A 3.3-kilobase-pair fragment of Pseudomonas aeruginosa DNA containing the phospholipase C (heat-labile hemolysin) gene was sequenced, and the location of the gene was determined. The gene product contains at its NH2 terminus a 38-amino acid sequence which structurally resembles the signal peptides of other secreted proteins but is unusually long and positively charged (6+). The location of the translation start codon was determined by constructing a series of plasmids in which the promoter of a transcription vector was ligated to Pseudomonas DNA containing deletions at the 5' end of the gene. The plasmids were used to transform Escherichia coli, and the resulting clones were assayed for hemolysin activity. In addition, sizes of truncated proteins produced by mutants with translation terminators introduced at specific sites were analyzed in E. coli maxicells. The gene is transcribed, starting just upstream of the hemolysin gene, as an mRNA of approximately 2,800 bases. Analysis of the nucleotide sequence, analysis of mutants in maxicells, and transcriptional studies indicate that the hemolysin is part of an operon composed of two genes. Phosphate regulation of the operon is at the transcriptional level. The location of the 5' end of the transcript was determined by S1 mapping.

Assembly of DNA polymerase III holoenzyme: co-assembly of gamma and tau is inhibited by DnaX complex accessory proteins but stimulated by DNA polymerase III core.

Although the two alternative Escherichia coli dnaX gene products, tau and gamma, are found co-assembled in purified DNA polymerase III holoenzyme, the pathway of assembly is not well understood. When the 10 subunits of holoenzyme are simultaneously mixed, they rapidly form a nine-subunit assembly containing tau but not gamma. We developed a new assay based on the binding of complexes containing biotin-tagged tau to streptavidin-coated agarose beads to investigate the effects of various DNA polymerase III holoenzyme subunits on the kinetics of co-assembly of gamma and tau into the same complex. Auxiliary proteins in combination with delta' almost completely blocked co-assembly, whereas chipsi or delta' alone slowed the association only moderately compared with the interaction of tau with gamma alone. In contrast, DNA polymerase III core, in the absence of deltadelta' and chipsi, accelerated the co-assembly of tau and gamma, suggesting a role for DNA polymerase III' [tau(2)(pol III core)(2)] in the assembly pathway of holoenzyme.

Replication of linear mitochondrial DNA from Paramecium: sequence and structure of the initiation-end crosslink.

Replication of the 14-micrometer linear Paramecium mitochondrial DNA is initiated by a crosslinking of the duplex strands at the initiation end of the molecule. As a consequence of the crosslink, a head-to-head dimer molecule, or palindrome, is a replicative intermediate. The central region of the dimer molecules of two species was cloned and sequenced, In the distal regions, the sequence is palindromic as expected; however, in the central region, there is a nonpalindromic sequence that is rich in A + T and contains direct tandem repeats. It is proposed that the nonpalindromic sequence constitutes the crosslink. Implications for the replication scheme are discussed. The model is unlike any other for a linear DNA.

Structural and functional analysis of the origin of replication of mitochondrial DNA from Paramecium aurelia : I. Inverted complements form the terminal loop.

Initiation of replication of the linear mitochondrial DNA from Paramecium occurs at a unique cross-linked terminus of the monomer molecule. Dimer length molecules, containing head-to-head monomers, are replicative intermediates. Previous studies have been with cloned dimer initiation region fragments but here we have isolated and sequenced isomeric forms of restriction fragments located at the initiation end of the monomer. The sequence isomers are inverted complements of each other in the region identified as the single-stranded DNA terminal loop. The unusual electrophoretic behaviour of these terminal restriction fragments supports the sequence data result that the loop is single stranded. These structural features are discussed in regard to mechanisms for the processing of dimer to monomer molecules.

Nucleotide sequence identifies Vilyuisk virus as a divergent Theiler's virus.

The Vilyuisk virus, originally thought to be the cause of a degenerative neurological disease of inhabitants of Siberia, has been characterized by sequence analysis of its 5' noncoding and coat protein coding regions. In the 5' noncoding, leader, and VP4 regions, the nucleotide identity between the sequences of known strains of Theiler's virus and Vilyuisk virus is about 90%. In the VP1-encoding region, the similarity drops to about 66% compared to the 50% similarity between sequences of Theiler's virus and encephalomyocarditis virus. Using the known crystal structure of one Theiler's virus strain, it is shown that the sequence heterogeneities generally occur at exposed surface residues. Vilyuisk virus is the most divergent Theiler's virus known. A tissue culture-adapted isolate has been propagated and found to exhibit low neurovirulence in CD-1 mice.