Biomedical subjects

J Cooley

Publications and source records attributed to J Cooley.

22 records · Page 2Linked to original sources

PubMed1975

Behavioral similarity as a reinforcer for preschool children.

Three experiments evaluated whether behavioral similarity provided by an adult could serve as a reinforcer for the modelling behavior of four preschoolers. In each experiment, sessions consisted of two kinds of trials: (1) experimenter-modelled trials, when the child's imitation of modelled motor responses was reinforced with praise and tokens, and (2) child-modelled trials when experimenter imitation of child-modelled responses was contingent upon the child's modelling one of three alternative responses: operation of a ball, horn, or clicker. Experiment I showed that the children consistently modelled whichever responses the experimenter imitated. Experiment II determined whether that performance was due to differences in the amount of experimenter behavior following imitated versus nonimitated child models or to experimenter imitation. Neither reducing nor increasing the amount of experimenter behavior following the children's nonimitated models altered their modelling of imitated responses. Experiment III evaluated whether experimenter imitation of child models was a reinforcer because the child's imitative responses were reinforced on experimenter-modelled trials. In Experiment III, the children's nonimitation of experimenter-models was reinforced with praise and tokens on a schedule of differential reinforcement of other behavior, yet they continued to model experimenter-imitated responses on child-modelled trials. These results indicate behavioral similarity was reinforcing, though no conditioning history through which it acquired that function was demonstrated.

Journal Article↗

PubMedDate not supplied

A novel protocol to identify mutations in patients with wiskott-Aldrich syndrome.

Mutations of WASP (Wiskott-Aldrich syndrome protein) underlie the severe immunodeficiency/platelet disorder Wiskott-Aldrich syndrome (WAS) and its milder variant X-linked thrombocytopenia (XLT). The affected gene, a 12-exon structure on the X-chromosome, is expressed exclusively in blood cells. The encoded product WASP is a 502-amino-acid scaffolding protein that functions in stimulus-induced nucleation of actin filaments to form dynamic cell surface projections. To date, more than 150 mutations have been identified in 300 WAS/XLT kindred worldwide, generally through methodologies that include sophisticated exon screening steps such as single-strand conformation analysis. We report here a simpler protocol, which was designed for use in clinical settings to identify the mutations of newly diagnosed patients. The approach relies on directly sequencing amplified exons according to a staggered schedule based on statistical evaluation of previous cases. In a 2 1/2-year trial, samples from 28 consecutive patients were analyzed; these included 3 "blindly labeled" previously studied cases. The mutations that were identified include a broad spectrum (8 missense, 3 nonsense, 5 splice site mutations, 11 small insertion/deletions, 1 large deletion) and were broadly distributed (in 10 of the 12 exons). All mutations were verified and no discrepancies were encountered. Per patient, a mean of six DNA sequencing reactions and 6-7 h of staff effort sufficed for mutation identification and verification, indicating that the protocol is cost-effective. This cumulative experience demonstrates the suitability, reliability, and versatility of the new protocol.

Child, Preschool↗

PubMedDate not supplied

Technical note: a compact data logger for ambulatory skin temperature measurement.

A miniature, body-worn data logger has been developed for multi-channel recording of small changes in skin surface temperature. The unit has been designed for small size, long battery life and high accuracy together with full programmability and an infra-red (contactless) transfer of parameters and data. Temperature is measured using thermistors with a resolution of 0.005 degrees C and an absolute accuracy of better than 0.05 degrees C. A comprehensive software package running on a laptop PC is used for initial setting of the logger parameters and downloading and displaying the temperature data. The present system records eight channels of temperature at intervals from 30 seconds to 99 minutes. It contains 64 K bytes of non-volatile memory allowing 3274 sets of readings including subject identification, battey status, date and time. The logger size is 55 mm x 31 mm x 9.5 mm and weighs 20 g.

Calibration↗

PubMedDate not supplied

Methotrexate in Crohn's disease: results of a randomized, double-blind, placebo-controlled trial.

BACKGROUND/AIMS: Immunosuppression with methotrexate may be useful in the treatment of Crohn's disease. We tested the efficacy of methotrexate in refractory Crohn's disease in a randomized, controlled trial. METHODOLOGY: Randomized, double-blind placebo-controlled trial of methotrexate in 33 patients with steroid-dependent Crohn's disease, 33% of whom had previously failed therapy with 6-mercaptopurine. Patients were given placebo or oral methotrexate 15 mg/week, or adjusted up to 22.5 mg/week, for up to 1 year or until treatment failure. Outcome was assessed by reduction in prednisone dosage, Crohn's Disease Activity Index, hospital admission, and laboratory parameters. RESULTS: Four patients were dropped from the study for non-compliance and one because of intercurrent illness, and 28 patients could be evaluated. Fewer methotrexate-treated patients (6/13 or 46%) had flares of Crohn's disease as compared to placebo-treated patients (12/15 or 80%), but this did not achieve statistical significance (p<0.1). There was a non-significant trend toward an increased number of significant side effects in the methotrexate-treated patients (3/13 or 23%) as compared to the placebo-treated patients (0/15 or 0%) (p<0.2). Laboratory indices of inflammation did not differ between the two groups. CONCLUSIONS: The methotrexate-treated group showed a trend toward fewer Crohn's disease flares, balanced by an increased number of significant side effects.

Administration, Oral↗