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1.
J Autism Dev Disord ; 53(3): 1117-1129, 2023 Mar.
Article in English | MEDLINE | ID: mdl-35717449

ABSTRACT

The purpose of the present study was to evaluate the effects of multiple exemplar training and social reinforcement on the maintenance and generalization of joint attention initiations across toy classes. Three children with autism spectrum disorder (ASD) participated. After analyzing samples of joint attention initiations from neurotypical peers, a composite score was developed and used to evaluate joint attention initiations of the children with ASD. Gaze shifting and commenting were taught using social reinforcement in a multiple exemplar format. Training sessions were followed by probes of untrained stimuli both within and across toy classes. Results showed that the participants acquired both gaze shifting and commenting using social consequences as reinforcers. Following training, participants initiated joint attention with a frequency within the range of their typically developing peers. Multiple exemplar training was also effective in facilitating acquisition within classes and joint attention maintenance during follow-up probes. Additionally, all participants generalized the acquired skills to a class of untrained stimuli.


Subject(s)
Autism Spectrum Disorder , Child , Humans , Generalization, Psychological , Peer Group , Attention
2.
Rapid Commun Mass Spectrom ; 36(21): e9380, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-35986908

ABSTRACT

RATIONALE: The last decade has seen a dramatic increase in the application of serial sampling of human dentine in archaeology. Rapid development in the field has provided many improvements in the methodology, in terms of both time resolution as well as the ability to integrate more isotope systems in the analysis. This study provides a comparison of two common sampling approaches, allowing researchers to select the most suitable approach for addressing specific research questions. METHODS: Two common approaches for sequential sampling of human dentine (micro-punches and micro-slices) are compared in terms of viability and efficacy. Using archaeological deciduous second molars and permanent first molars, this study demonstrates how the two approaches capture aspects of the weaning process in different ways. In addition, different aspects related to the extraction protocols, such as the thickness of the central slide and the solubilisation step, are also evaluated. RESULTS: While both approaches show similar intra-tooth isotopic patterns, the micro-punches approach is preferable for research that requires a very fine temporal resolution, while the micro-slices approach is best for research where δ34 S values are needed, or when the samples are poorly preserved. In addition, the solubilisation step has a large effect on collagen yield, and, to a lesser extent, on isotopic compositions. Therefore, it is important to ensure that only samples that have undergone the same pre-treatment protocol are directly compared. CONCLUSIONS: We present the pros and cons of the two micro-sampling approaches and offer possible mitigation strategies to address some of the most important issues related to each approach.


Subject(s)
Dentin , Tooth , Collagen , Dentin/chemistry , Humans , Molar/chemistry , Nitrogen Isotopes/analysis , Tooth/chemistry
3.
Behav Anal Pract ; 9(4): 299-308, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27920961

ABSTRACT

The supervision of professionals in the field of behavior analysis is multifaceted. The BACB® Professional and Ethical Compliance Code for Behavior Analysis provides guidance for effective supervisory practices, as supervision impacts both the supervisee and the consumers. The purpose of this article is (1) to discuss rationales and consequences relative to supervision issues, (2) to provide directions for professional development in each of the seven identified supervisory areas within the code, and (3) to set the occasion for critical discourse relative to supervision. Case examples are used to illustrate each of the seven supervisory subcomponents of the "Behavior Analysts as Supervisors" section of the Code. A rationale is provided for each component, as well as a discussion of possible undesirable consequences resulting from not following the rule. While the code provides clear expectations of the desired behavior, this article explores more of the subtle nuances inherent in each section of the supervision code, with the goal of achieving a better understanding of the Code and enhancing supervisory skills.

4.
Sci Rep ; 6: 36249, 2016 11 08.
Article in English | MEDLINE | ID: mdl-27824097

ABSTRACT

Lake Ontario once supported a large complex of Atlantic Salmon (Salmo salar) populations that became extinct prior to scientific study. Since the 1860s, research efforts to conserve and reintroduce a sustainable population of Atlantic Salmon have focused on determining whether Lake Ontario's original salmon populations had migrated to the Atlantic Ocean as part of their lifecycle (anadromy), stayed in the lake year-round (potamodromy), or both. We used stable carbon, nitrogen, and sulfur isotope analyses of archaeological bones and historical museum-archived salmon scales to show that the original salmon populations from Lake Ontario completed their entire lifecycle without migrating to the Atlantic Ocean. With a time depth of more than 500 years, our findings provide a unique baseline with significant potential for informing modern restocking and conservation efforts.


Subject(s)
Animal Migration/physiology , Isotope Labeling/methods , Salmo salar/physiology , Animals , Atlantic Ocean , Behavior, Animal , Carbon Isotopes/analysis , Fossils , Nitrogen Isotopes/analysis , Sulfur Isotopes/analysis
5.
Res Dev Disabil ; 35(12): 3632-44, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25241118

ABSTRACT

Intensive behavioral intervention for young children diagnosed with autism can produce large gains in social, cognitive, and language development. Although several studies have identified behaviors that are possible indicators of best outcome, changes in performance are typically measured using norm-referenced standardized scores referencing overall functioning level rather than via repeated observational measures of autism-specific deficits (i.e., social behavior). In the current study, 83 children with autism (CWA), aged 1, 2 and 3 years, and 58 same-aged typically developing children (TDC) were directly observed in the areas of cognitive skills, joint attention (JA), play, and stereotypic behavior using a measure called the Early Skills Assessment Tool (ESAT; MacDonald et al., 2006). CWA were assessed at entry into an EIBI program and again after 1 year of treatment. Changes in performance were compared pre- and post-treatment as well as to the normative data by age. Results indicate significant gains on the ESAT across all age groups with the greatest gains seen in the children who entered treatment prior to their second birthday. Increases were seen on direct measures of JA, play, imitation and language while decreases were seen in stereotypy regardless of level of performance at entry into EIBI. The ESAT, a direct measurement tool, served as a sensitive tool to measure changes in autism symptomatology following EIBI treatment.


Subject(s)
Attention , Autistic Disorder/therapy , Behavior Therapy/methods , Cognition , Play and Playthings , Stereotyped Behavior , Age Factors , Autistic Disorder/diagnosis , Autistic Disorder/psychology , Case-Control Studies , Child, Preschool , Early Intervention, Educational , Humans , Infant , Reproducibility of Results , Treatment Outcome
6.
J Autism Dev Disord ; 44(1): 65-74, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23719854

ABSTRACT

We investigated the social validity of the NECC Core Skills Assessment (NECC-CSA) with parents and professionals as participants. The NECC-CSA is a measurement tool consisting of direct and indirect measures of skills important to all individuals with autism, across the lifespan. Participants (N = 245) were provided with a list of 66 skills, 47 of which were Core Skills from the NECC-CSA, and were asked to indicate which items they considered to be foundational. Participants endorsed items from the NECC-CSA as foundational skills, more than they endorsed the other items. Differences between parents and professionals are described and detailed with respect to individual assessment items. The NECC-CSA consists of socially validated skills that can be taken as a starting point for programs of instruction for individuals with ASDs.


Subject(s)
Child Development Disorders, Pervasive/psychology , Disability Evaluation , Social Behavior , Child , Female , Humans , Male , New England , Parents
7.
Bioorg Med Chem Lett ; 24(1): 353-9, 2014 Jan 01.
Article in English | MEDLINE | ID: mdl-24287381

ABSTRACT

The design, synthesis and structure-activity relationships of a series of oxazole-benzamide inhibitors of the essential bacterial cell division protein FtsZ are described. Compounds had potent anti-staphylococcal activity and inhibited the cytokinesis of the clinically-significant bacterial pathogen Staphylococcus aureus. Selected analogues possessing a 5-halo oxazole also inhibited a strain of S. aureus harbouring the glycine-to-alanine amino acid substitution at residue 196 of FtsZ which conferred resistance to previously reported inhibitors in the series. Substitutions to the pseudo-benzylic carbon of the scaffold improved the pharmacokinetic properties by increasing metabolic stability and provided a mechanism for creating pro-drugs. Combining multiple substitutions based on the findings reported in this study has provided small-molecule inhibitors of FtsZ with enhanced in vitro and in vivo antibacterial efficacy.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacterial Proteins/antagonists & inhibitors , Benzamides/pharmacology , Cytoskeletal Proteins/antagonists & inhibitors , Drug Design , Oxazoles/pharmacology , Staphylococcus aureus/drug effects , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Benzamides/chemistry , Dose-Response Relationship, Drug , Microbial Sensitivity Tests , Molecular Structure , Oxazoles/chemistry , Staphylococcus aureus/chemistry , Structure-Activity Relationship
8.
J Appl Behav Anal ; 46(3): 662-8, 2013.
Article in English | MEDLINE | ID: mdl-24114229

ABSTRACT

Children with autism often engage in repetitive play with little variation in the actions performed or items used. This study examined the use of video modeling with scripted substitutable loops on children's pretend play with trained and untrained characters. Three young children with autism were shown a video model of scripted toy play that included a substitutable loop that allowed various characters to perform the same actions and vocalizations. Three characters were modeled with the substitutable loop during training sessions, and 3 additional characters were present in the video but never modeled. Following video modeling, all the participants incorporated untrained characters into their play, but the extent to which they did so varied.


Subject(s)
Autistic Disorder/rehabilitation , Imitative Behavior/physiology , Play and Playthings , Videotape Recording , Autistic Disorder/psychology , Child , Generalization, Psychological , Humans , Male , Social Behavior
9.
Plant Cell Physiol ; 54(6): 859-74, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23444302

ABSTRACT

Synechocystis sp. strain PCC 6803 grows photoautotrophically across a broad pH range, but wild-type cultures reach a higher density at elevated pH; however, photoheterotrophic growth is similar at high and neutral pH. A number of PSII mutants each lacking at least one lumenal extrinsic protein, and carrying a second PSII lumenal mutation, are able to grow photoautotrophically in BG-11 medium at pH 10.0, but not pH 7.5. We investigated the basis of this pH effect and observed no pH-specific change in variable fluorescence yield from PSII centers of the wild type or the pH-dependent ΔPsbO:ΔPsbU and ΔPsbV:ΔCyanoQ strains; however, 77 K fluorescence emission spectra indicated increased coupling of the phycobilisome (PBS) antenna at pH 10.0 in all mutants. DNA microarray data showed a cell-wide response to transfer from pH 10.0 to pH 7.5, including decreased mRNA levels of a number of oxidative stress-responsive transcripts. We hypothesize that this transcriptional response led to increased tolerance against reactive oxygen species and in particular singlet oxygen. This response enabled photoautotrophic growth of the PSII mutants at pH 10.0. This hypothesis was supported by increased resistance of all strains to rose bengal at pH 10.0 compared with pH 7.5.


Subject(s)
Autotrophic Processes/radiation effects , Bacterial Proteins/genetics , Environment , Mutation/genetics , Photosystem II Protein Complex/genetics , Synechocystis/growth & development , Autotrophic Processes/drug effects , Bacterial Proteins/metabolism , Buffers , Chlorophyll/metabolism , Chlorophyll A , Culture Media/pharmacology , Gene Expression Regulation, Bacterial/drug effects , Gene Expression Regulation, Bacterial/radiation effects , Genes, Bacterial/genetics , Heterotrophic Processes/drug effects , Heterotrophic Processes/radiation effects , Hydrogen-Ion Concentration/drug effects , Kinetics , Models, Biological , Oxidative Stress/drug effects , Oxidative Stress/genetics , Oxidative Stress/radiation effects , Photosystem II Protein Complex/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rose Bengal/pharmacology , Singlet Oxygen/pharmacology , Spectrometry, Fluorescence , Synechocystis/drug effects , Synechocystis/genetics , Synechocystis/metabolism , Transcription, Genetic/drug effects , Transcription, Genetic/radiation effects
10.
Antimicrob Agents Chemother ; 57(1): 317-25, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23114779

ABSTRACT

The bacterial cell division protein FtsZ is an attractive target for small-molecule antibacterial drug discovery. Derivatives of 3-methoxybenzamide, including compound PC190723, have been reported to be potent and selective antistaphylococcal agents which exert their effects through the disruption of intracellular FtsZ function. Here, we report the further optimization of 3-methoxybenzamide derivatives towards a drug candidate. The in vitro and in vivo characterization of a more advanced lead compound, designated compound 1, is described. Compound 1 was potently antibacterial, with an average MIC of 0.12 µg/ml against all staphylococcal species, including methicillin- and multidrug-resistant Staphylococcus aureus and Staphylococcus epidermidis. Compound 1 inhibited an S. aureus strain carrying the G196A mutation in FtsZ, which confers resistance to PC190723. Like PC190723, compound 1 acted on whole bacterial cells by blocking cytokinesis. No interactions between compound 1 and a diverse panel of antibiotics were measured in checkerboard experiments. Compound 1 displayed suitable in vitro pharmaceutical properties and a favorable in vivo pharmacokinetic profile following intravenous and oral administration, with a calculated bioavailability of 82.0% in mice. Compound 1 demonstrated efficacy in a murine model of systemic S. aureus infection and caused a significant decrease in the bacterial load in the thigh infection model. A greater reduction in the number of S. aureus cells recovered from infected thighs, equivalent to 3.68 log units, than in those recovered from controls was achieved using a succinate prodrug of compound 1, which was designated compound 2. In summary, optimized derivatives of 3-methoxybenzamide may yield a first-in-class FtsZ inhibitor for the treatment of antibiotic-resistant staphylococcal infections.


Subject(s)
Anti-Bacterial Agents/pharmacokinetics , Bacterial Proteins/antagonists & inhibitors , Benzamides/pharmacokinetics , Cytoskeletal Proteins/antagonists & inhibitors , Methicillin-Resistant Staphylococcus aureus/drug effects , Oxazoles/pharmacokinetics , Prodrugs/pharmacokinetics , Staphylococcal Infections/drug therapy , Staphylococcus epidermidis/drug effects , Succinates/pharmacokinetics , Administration, Oral , Animals , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Benzamides/chemical synthesis , Benzamides/chemistry , Benzamides/pharmacology , Biological Availability , Colony Count, Microbial , Cytokinesis/drug effects , Cytoskeletal Proteins/genetics , Drug Resistance, Multiple, Bacterial , Female , Injections, Intravenous , Methicillin-Resistant Staphylococcus aureus/genetics , Methicillin-Resistant Staphylococcus aureus/growth & development , Mice , Microbial Sensitivity Tests , Mutation , Oxazoles/chemical synthesis , Oxazoles/pharmacology , Prodrugs/chemical synthesis , Prodrugs/pharmacology , Staphylococcal Infections/microbiology , Staphylococcus epidermidis/growth & development , Succinates/chemical synthesis , Succinates/pharmacology , Succinic Acid/chemistry , Thigh/microbiology , Treatment Outcome
11.
Am J Respir Crit Care Med ; 185(8): 862-73, 2012 Apr 15.
Article in English | MEDLINE | ID: mdl-22323305

ABSTRACT

RATIONALE: Unrecognized airway infection and inflammation in young children with cystic fibrosis (CF) may lead to irreversible lung disease; therefore early detection and treatment is highly desirable. OBJECTIVES: To determine whether the lung clearance index (LCI) is a sensitive and repeatable noninvasive measure of airway infection and inflammation in newborn-screened children with CF. METHODS: Forty-seven well children with CF (mean age, 1.55 yr) and 25 healthy children (mean age, 1.26 yr) underwent multiple-breath washout testing. LCI within and between-test variability was assessed. Children with CF also had surveillance bronchoalveolar lavage performed. MEASUREMENTS AND MAIN RESULTS: The mean (SD) LCI in healthy children was 6.45 (0.49). The LCI was higher in children with CF (7.21 [0.81]; P < 0.001). The upper limit of normal for the LCI was 7.41. Fifteen (32%) children with CF had an elevated LCI. LCI measurements were repeatable and reproducible. Airway infection was present in 17 (36%) children with CF, including 7 (15%) with Pseudomonas aeruginosa. Polymicrobial growth was associated with worse inflammation. The LCI was higher in children with Pseudomonas (7.92 [1.16]) than in children without Pseudomonas (7.02 [0.56]) (P = 0.038). The LCI correlated with bronchoalveolar lavage IL-8 (R(2) = 0.20, P = 0.004) and neutrophil count (R(2) = 0.21, P = 0.001). An LCI below the upper limit of normality had a high negative predictive value (93%) in excluding Pseudomonas. CONCLUSIONS: The LCI is elevated early in CF, especially in the presence of Pseudomonas and airway inflammation. The LCI is a feasible, repeatable, and sensitive noninvasive marker of lung disease in young children with CF.


Subject(s)
Bronchoalveolar Lavage Fluid/microbiology , Cystic Fibrosis/diagnosis , Lung Diseases/diagnosis , Pulmonary Gas Exchange/physiology , Australia , Case-Control Studies , Child, Preschool , Cystic Fibrosis/complications , Early Diagnosis , Female , Forced Expiratory Volume , Humans , Infant , Lung Diseases/etiology , Lung Diseases/microbiology , Male , Pseudomonas Infections/diagnosis , Pseudomonas Infections/etiology , Pseudomonas aeruginosa/isolation & purification , ROC Curve , Reference Values , Retrospective Studies , Severity of Illness Index , Statistics, Nonparametric
12.
J Med Chem ; 53(10): 3927-36, 2010 May 27.
Article in English | MEDLINE | ID: mdl-20426423

ABSTRACT

3-Methoxybenzamide (1) is a weak inhibitor of the essential bacterial cell division protein FtsZ. Alkyl derivatives of 1 are potent antistaphylococcal compounds with suboptimal drug-like properties. Exploration of the structure-activity relationships of analogues of these inhibitors led to the identification of potent antistaphylococcal compounds with improved pharmaceutical properties.


Subject(s)
Anti-Bacterial Agents/chemical synthesis , Bacterial Proteins/antagonists & inhibitors , Cytoskeletal Proteins/antagonists & inhibitors , Pyridines/chemical synthesis , Staphylococcus aureus/drug effects , Thiazoles/chemical synthesis , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Biological Availability , Blood Proteins/metabolism , Caco-2 Cells , Cell Division/drug effects , Cell Membrane Permeability , Hepatocytes/metabolism , Humans , Mice , Microbial Sensitivity Tests , Models, Molecular , Protein Binding , Pyridines/chemistry , Pyridines/pharmacology , Staphylococcal Infections/drug therapy , Staphylococcus aureus/cytology , Structure-Activity Relationship , Thiazoles/chemistry , Thiazoles/pharmacology
13.
J Appl Behav Anal ; 42(1): 43-55, 2009.
Article in English | MEDLINE | ID: mdl-19721729

ABSTRACT

The purpose of the present study was to use video modeling to teach children with autism to engage in reciprocal pretend play with typically developing peers. Scripted play scenarios involving various verbalizations and play actions with adults as models were videotaped. Two children with autism were each paired with a typically developing child, and a multiple-probe design across three play sets was used to evaluate the effects of the video modeling procedure. Results indicated that both children with autism and the typically developing peers acquired the sequences of scripted verbalizations and play actions quickly and maintained this performance during follow-up probes. In addition, probes indicated an increase in the mean number of unscripted verbalizations as well as reciprocal verbal interactions and cooperative play. These findings are discussed as they relate to the development of reciprocal pretend-play repertoires in young children with autism.


Subject(s)
Autistic Disorder/psychology , Education, Special/methods , Play and Playthings/psychology , Videotape Recording/methods , Child , Child, Preschool , Female , Humans , Imitative Behavior , Male , Observer Variation , Peer Group , Social Behavior
14.
Res Autism Spectr Disord ; 3(1): 42-49, 2009 Jan 01.
Article in English | MEDLINE | ID: mdl-20046922

ABSTRACT

Three young children diagnosed with autism did not reliably locate objects in the environment on the basis of an adult's gaze shifts. A training program designed to teach gaze following used the activation of remote controlled mechanical toys as both prompts and consequences. Over several training sessions, toy activation was progressively delayed following the adult's gaze-shift cues. All of the children eventually came to anticipate the toy activation and locate the target object on the basis of the adult's gaze-shift cue alone. Discrimination of another person's gaze direction is discussed in relation to joint attention deficits in children with autism.

15.
Acta Biomater ; 4(6): 1583-92, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18706876

ABSTRACT

Carbon nanotubes are attractive as additives in fiber-reinforced composites due to their high aspect ratio, strength and electrical conductivity. In the present study, solubilized collagen Type I was polymerized in the presence of dispersed single-walled carbon nanotubes (SWNT) and human dermal fibroblast cells (HDF) to produce collagen-SWNT composite biomaterials with HDF embedded directly in the matrix. The resulting constructs, with SWNT loadings of 0 (control), 0.8, 2.0 and 4.0 wt.% SWNT, were cultured and electrical properties were evaluated in the frequency range 5-500 kHz at days 3 and 7. All collagen-SWNT hydrogel matrices underwent HDF-mediated gel compaction over time in culture, but the presence of SWNT significantly decreased the rate and extent of gel compaction. Viability of HDF in all constructs was consistently high and cell morphology was not affected by the presence of SWNT. However, cell number at day 7 in culture decreased with increasing SWNT loading. Electrical conductivity of the constructs varied from 3 to 7 mS cm(-1), depending on SWNT loading level. Conductivity increased uniformly with increasing wt.% of SWNT (R=0.78) and showed a modest frequency dependence, suggesting that the electrical percolation threshold had not been reached in these materials. These data demonstrate that the electrical conductivity of cell-seeded collagen gels can be increased through the incorporation of carbon nanotubes. Protein-SWNT composite materials may have application as scaffolds for tissue engineering, as substrates to study electrical stimulation of cells, and as transducers or leads for biosensors.


Subject(s)
Electric Conductivity , Fibroblasts/metabolism , Hydrogels/chemistry , Nanotubes, Carbon/chemistry , Biocompatible Materials/chemistry , Cell Line , Cell Survival , Collagen/chemistry , Equipment Design , Humans , Materials Testing , Models, Biological , Nanotechnology/methods , Tissue Engineering/methods
16.
J Biomed Mater Res A ; 86(1): 269-77, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18428799

ABSTRACT

Composite biomaterials incorporating fibroblast cells, collagen Type I, fibrin, and 2 wt % carboxylated SWNT were created, and their properties were compared with similar control constructs without SWNT. Alignment of the matrix was stimulated by application of 8% cyclic strain for three 12-h periods over three days. All constructs underwent cell-mediated gel compaction to 15-20% of their initial volume, which was not affected by SWNT loading. Mechanical strain increased the rate of compaction, and strained constructs were significantly more compacted than unstrained controls by day 3. Cell viability and morphology were similar in both control and SWNT-loaded constructs, but unstrained samples exhibited a more stellate appearance with more numerous cellular projections. Application of mechanical strain caused clear alignment of both the cells and matrix in the direction of the applied strain. Bioimpedance measurements showed that SWNT loading increased the electrical conductivity of composite constructs, and that mechanically-induced alignment of the matrix/SWNT caused a further increase in conductivity. These results demonstrate that SWNT can be used to augment the electrical properties of 3D protein hydrogels, and that anisotropy in the matrix further enhances these properties. Such electrically conductive biopolymers may have a variety of applications in tissue engineering and biosensor development.


Subject(s)
Biocompatible Materials/chemistry , Collagen/chemistry , Fibrin/chemistry , Nanotechnology/methods , Nanotubes, Carbon/chemistry , Bioreactors , Cell Survival , Cells, Cultured , Electric Conductivity , Electric Impedance , Equipment Design , Humans , Hydrogels/chemistry , Skin/cytology , Stress, Mechanical
17.
J Appl Behav Anal ; 40(2): 263-75, 2007.
Article in English | MEDLINE | ID: mdl-17624067

ABSTRACT

Previous research implies that stereotypic behavior tends to be maintained by the sensory consequences produced by engaging in the response. Few investigations, however, have focused on vocal stereotypy. The current study examined the noncommunicative vocalizations of 4 children with an autism spectrum disorder. First, functional analyses were conducted in an attempt to identify the function of each child's behavior. For each of the participants, it was found that vocal stereotypy was likely not maintained by the social consequences. Following assessment, response interruption and redirection (RIRD) was implemented in an ABAB design to determine whether vocal stereotypy could be successfully redirected. RIRD involved a teacher issuing a series of vocal demands the child readily complied with during regular academic programming. Vocal demands were presented contingent on the occurrence of vocal stereotypy and were continuously presented until the child complied with three consecutively issued demands without emitting vocal stereotypy. For each child, RIRD produced levels of vocal stereotypy substantially lower than those observed in baseline. For 3 of the children, an increase in appropriate communication was also observed. The children's teachers were trained to implement RIRD. Brief follow-up probes and anecdotal information implied that the treatment had a positive impact in the natural environment.


Subject(s)
Autistic Disorder/psychology , Phonation , Psychomotor Disorders/diagnosis , Psychomotor Disorders/therapy , Stereotyped Behavior , Child , Extinction, Psychological , Female , Humans , Male , Reinforcement, Psychology , Severity of Illness Index
18.
Res Dev Disabil ; 28(3): 266-77, 2007.
Article in English | MEDLINE | ID: mdl-16814515

ABSTRACT

Although stereotypy is one of the key diagnostic features of autism, few studies have compared stereotypic behavior in children with autism and typically developing children. The present study employed direct observational measurement methods to assess levels of stereotypic behavior in 2-, 3- and 4-year-old children with autism or pervasive developmental disorder - not otherwise specified (PDD-NOS) and age-matched typically developing peers. Thirty children with autism or PDD-NOS and 30 typically developing children participated. Each child's performance of several early learning and play skills was assessed using a direct observational assessment protocol developed for children with autism who were entering early intensive behavioral treatment. Duration of episodes of vocal and motor stereotypy was recorded from a videotaped 10 min portion of that assessment session. Results indicated that the 2-year-old children with autism or PDD-NOS had somewhat higher levels of stereotypic behavior than the typically developing 2-year-olds, while the 3- and 4-year-old children with autism or PDD-NOS displayed substantially higher levels stereotypic behavior than their same-age peers.


Subject(s)
Autistic Disorder/diagnosis , Child Development Disorders, Pervasive/diagnosis , Stereotyped Behavior , Age Factors , Autistic Disorder/psychology , Autistic Disorder/therapy , Behavior Therapy , Child Development Disorders, Pervasive/psychology , Child Development Disorders, Pervasive/therapy , Child, Preschool , Early Intervention, Educational , Female , Humans , Male , Reference Values
19.
Res Dev Disabil ; 27(2): 138-50, 2006.
Article in English | MEDLINE | ID: mdl-15979843

ABSTRACT

This paper describes a highly structured assessment protocol with objective behavioral measures for joint attention responding and initiation. The assessment was given to 26 children diagnosed with autism spectrum disorders and 21 typically developing children, aged two to four years. Interobserver agreement was high for all behavioral measures. Children with autism had relatively minor deficits in joint attention responding and more severe deficits in joint attention initiation, relative to typically developing children. These results replicate those reported in previous research. The protocol can be used reliably to assess behavior indicative of joint attention responding and initiation in typically developing children and children with autism.


Subject(s)
Attention , Autistic Disorder/psychology , Mental Disorders/etiology , Child , Child, Preschool , Female , Gestures , Humans , Male , Mental Disorders/diagnosis , Mental Disorders/epidemiology , Observer Variation , Verbal Behavior
20.
J Biomed Mater Res A ; 74(3): 489-96, 2005 Sep 01.
Article in English | MEDLINE | ID: mdl-15973695

ABSTRACT

Carbon nanotubes (CNT) are attractive for use in fiber-reinforced composite materials due to their very high aspect ratio, combined with outstanding mechanical and electrical properties. Composite materials comprising a collagen matrix with embedded CNT were prepared by mixing solubilized Type I collagen with solutions of carboxylated single-walled carbon nanotubes (SWNT) at concentrations of 0, 0.2, 0.4, 0.8, and 2.0 weight percent. Living smooth muscle cells were incorporated at the time of collagen gelation to produce cell-seeded collagen-CNT composite matrices. Constructs containing 2.0 wt % CNT exhibited delayed gel compaction, relative to lower concentrations that compacted at the same rate as pure collagen controls. Cell viability in all constructs was consistently above 85% at both Day 3 and Day 7, whereas cell number in CNT-containing constructs was lower than in control constructs at Day 3, though statistically unchanged by Day 7. Scanning electron microscopy showed physical interactions between CNT and collagen matrix. Raman spectroscopy confirmed the presence of CNT at the expected diameter (0.85-1.30 nm), but did not indicate strong molecular interactions between the collagen and CNT components. Such collagen-CNT composite matrices may have utility as scaffolds in tissue engineering, or as components of biosensors or other medical devices.


Subject(s)
Biocompatible Materials , Collagen , Nanotubes, Carbon , Tissue Engineering , Animals , Cells, Cultured , Microscopy, Electron, Scanning , Models, Biological , Myocytes, Smooth Muscle/ultrastructure , Nanotubes, Carbon/ultrastructure , Rats , Spectrum Analysis, Raman
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