Biomedical subjects

F O'brien

Publications and source records attributed to F O'brien.

8 recordsLinked to original sources

PubMed2001

Basophil recruitment and IL-4 production during human allergen-induced late asthma.

BACKGROUND: Basophils represent an important source of inflammatory mediators and cytokines after IgE-dependent activation in human beings. OBJECTIVE: To assess the role of basophils in allergic asthma, we measured the number of basophils in the bronchial mucosa and their capacity to express IL-4 mRNA and protein during allergen-induced late asthmatic responses. METHODS: Fiberoptic bronchoscopic bronchial biopsies were obtained at 24 hours from sites of segmental bronchial allergen challenge and control sites in 19 patients with atopic asthma and 6 nonatopic healthy volunteers. Basophil numbers were assessed by immunohistochemistry through use of mAb 2D7. IL-4 mRNA--positive cells were detected through use of in situ hybridization and colocalized to basophils through use of sequential immunohistochemistry/in situ hybridization. IL-4 protein was detected and colocalized to basophils through use of dual immunohistochemistry. RESULTS: After allergen challenge, there was an increase in the median number of 2D7-positive basophils per square millimeter in the bronchial mucosa in patients with asthma (0.9 cells/mm(2) at baseline to 8.8 cells/mm(2) after challenge; P =.002), which also was significantly higher than what was seen in nonasthmatic controls (P =.01). Similarly, IL-4 mRNA--positive cells were increased at 24 hours in patients with asthma (1.4 to 14) in comparison with controls (0 to 0; P =.02). Colocalization studies revealed that 15% and 41% of the basophil population in patients with asthma after allergen-challenge expressed, respectively, IL-4 mRNA and protein. Conversely, 19% of IL-4 mRNA-positive cells and 72% of IL-4 protein--positive cells were accounted for by basophils. CONCLUSION: After allergen provocation in sensitive patients with atopic asthma, basophils are recruited to the bronchial mucosa and express IL-4 mRNA and protein, which might contribute to local IgE synthesis and/or tissue eosinophilia or other aspects of allergic inflammation during late responses and ongoing asthma.

Adult↗

PubMed1972

Training profoundly retarded children to stop crawling.

Many profoundly retarded children continue to crawl even though they can walk. Crawling and walking were viewed as two alternative response modes, both reinforced by movement. Children choose the one mode that is easier and faster for them. A training program was designed to increase the ease and speed of walking relative to that of crawling, and consisted of restraint-for-crawling and priming-of-walking. With the program, four retarded children reduced crawling and began to walk instead. When training was discontinued, two children with moderate walking impairment continued to walk rather than crawl. Two children with severe impairment of walking, however, required the occasional use of the restraint procedure to maintain walking as the dominant mode of locomotion. The program was easily administered, required little time, and was effective for all four children.

Journal Article↗

PubMed1972

Developing proper mealtime behaviors of the institutionalized retarded.

The institutionalized mentally retarded display a variety of unsanitary, disruptive, and improper table manners. A program was developed that included (1) acquisition-training of a high standard of proper table manners and (2) maintenance procedures to provide continued motivation to maintain proper mealtime behaviors and decrease improper skills. Twelve retardates received acquisition training, individually, by a combination of verbal instruction, imitation, and manual guidance. The students then ate in their group dining arrangement where the staff supervisor provided continuing approval for proper manners and verbal correction and timeout for improper manners. The results were: (1) the trained retardates showed significant improvement, whereas those untrained did not; (2) the trained retardates ate as well in the institution as non-retarded customers did in a public restaurant; (3) proper eating was maintained in the group dining setting; (4) timeout was rarely needed; (5) the program was easily administered by regular staff in a regular dining setting. The rapidity, feasibility, and effectiveness of the program suggests the program as a solution to improper mealtime behaviors by the institutionalized mentally retarded.

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PubMed1972

Training and maintaining a retarded child's proper eating.

The present study was designed to explore whether motivational procedures are needed to maintain a retardate's continued use of previously trained eating skills. A profoundly retarded child who ate food with her hands was trained by a manual guidance procedure to eat properly with a spoon, but the child still did not use the spoon after having learned to do so. When a motivational-maintenance procedure was applied, the child did begin to eat properly. When maintenance was discontinued, the child returned to eating with her hands. Proper eating returned when maintenance was applied again; when discontinued, the child returned to eating with her hands. These results demonstrate that continued motivational procedures are needed after training to maintain the retardate's continued use of proper eating skills.

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PubMed1971

Behavioral engineering: two apparatuses for toilet training retarded children.

Daytime incontinence is a major problem for retarded children. A training procedure for eliminating this problem should be facilitated by an apparatus that provided the trainer with an immediate signal when the child voided so that the trainer could react immediately. Two apparatuses were developed for this purpose: a toilet-chair apparatus to signal proper toileting and a portable pants-alarm apparatus to signal wetting of the pants. A reprimand was given when pants wetting occurred whereas positive reinforcement was given for proper toileting. Results with four profoundly retarded children indicated the reliability of the apparatuses in practice and the effectiveness of a toilet training program that used the two apparatuses.

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PubMed1970

Behavioral engineering: control of posture by informational feedback.

The effects of informational feedback on a socially undesirable behavior were studied. The feedback was a mild vibrotactile stimulus and the response was slouching. When subjects slouched, a behavioral engineering apparatus provided vibrotactile stimulation to the shoulder. All subjects slouched less when stimulation was provided. A procedural control revealed that slouching will decrease because of the informational aspect of the stimulus consequence and not because of its aversive properties. When the subjects were instructed to slouch, the effects of feedback were reversed: feedback increased, rather than decreased, slouching. These results indicate that the effect of feedback for a response depends on the subject's motivation to perform that response. It is suggested that informational feedback could be used more widely as a therapeutic procedure to modify human behaviors, but only those behaviors that a patient is strongly motivated to change.

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PubMed1969

Increased communications of chronic mental patients by reinforcement and by response priming.

An attempt was made to increase the frequency with which chronic schizophrenic patients suggested feasible improvements in their treatment. A response priming procedure was devised that was comparable to a previously developed reinforcer exposure procedure. The patients were required to attend a structured meeting during which they were prompted to make suggestions. This priming procedure was compared with the more usual procedure of "welcoming" attendance and suggestions. It was found that more suggestions were made when attendance was required, rather than optional. This increase occurred during a group as well as a private meeting. An attempt was then made to analyze the probable reinforcer for the suggestions by experimentally varying the percentage of suggestions followed. Different staff members served as the discriminative stimuli within a multiple schedule. It was found that the number of suggestions was a direct function of the percentage followed. These results demonstrate the effectiveness of the priming procedure as an adjunct to reinforcement procedures for increasing desired behaviors of mental patients. Few suggestions were made when reinforcement or priming were used alone.

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PubMed1968

Behavioral engineering: postural control by a portable operant apparatus.

Recent studies suggested a general behavioral engineering approach to behavioral disorders by portable operant treatment instruments. The approach was applied to the problem of poor posture, specifically rounding of the back or slouching. An apparatus was developed that provided a warning stimulus followed by an aversive tone for the duration of slouching. Slouching was thereby punished by onset of the tone, and non-slouching was reinforced by tone termination and postponement. Twenty-five adults wore the apparatus during their normal working day during alternate periods in which the aversive tone was connected and disconnected experimentally. A miniature time-meter recorded the duration of slouching. The results showed that slouching decreased for each subject during each period in which slouching produced the aversive tone. For two subjects, a second control procedure was applied in which slouching terminated the tone. The result was an increase of slouching, demonstrating that the postural changes were controlled by the scheduled relation between the aversive tone and the response, and not by other factors such as simple response feedback. The substantial changes in posture indicate that the present procedure may prove to be an effective treatment alternative and suggests the general value of the behavioral engineering approach.

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