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C Pert

Publications and source records attributed to C Pert.

11 recordsLinked to original sources

Contingent reinforcement or defending the self? A review of evolving models of aggression in people with mild learning disabilities.

This paper examines the changing approaches to working with people with a moderate to mild learning disability, who are frequently aggressive. Long-held assumptions about the lack of inter-personal understanding and impulsiveness continue to play a central role in clinical assessment and intervention for this group. Yet, there is a lack of controlled studies indicating the influence of such factors in frequent aggression. The dominant behavioural tradition has long encouraged such assumptions, but has focused on people with more severe disabilities where such assumptions are arguably more appropriate. The current review of the literature shows a clear evolution away from a strict behavioural approach towards cognitive-behavioural therapy (CBT) approaches that take account of the heterogeneous psychosocial causes of aggression. We find support for CBT in the child-development literature, which examines inter-personal difficulties from an information-processing perspective. Finally, we argue that much of the literature implicitly utilizes the concept of self, and we suggest that this should be made explicit in a reformulated theory of the 'person', incorporating the self concept and embedding individual cognitive processes and behaviour in a social context.

Aggression↗

Attribution of intent and role-taking: cognitive factors as mediators of aggression with people who have mental retardation.

An assessment task was devised to explore the attributional style and role-taking ability of 22 aggressive and 22 nonaggressive adults with moderate to mild mental retardation. Aggressive participants showed a hostile bias in their interpretation of others' intentions towards themselves within ambiguous interpersonal situations, although no difference was found across groups within clearly provocative situations. Furthermore, the role-taking ability of the aggressive participants was superior to the nonaggressive group, undermining the focus on global problems of interpersonal understanding as a causal factor of aggression for people with mental retardation.

Adolescent↗

Facing stress and conflict: a comparison of the predicted responses and self-concepts of aggressive and non-aggressive people with intellectual disability.

The present research consisted of two studies. A total of 44 participants were involved in the first study: 22 individuals with problems of aggression (Ag) and 22 non-aggressive (NAg) individuals. A sentence completion test was used to explore whether there were differences between the two groups' predicted coping responses in stressful situations. While the Ag group provided most aggressive responses, the NAg participants were more assertive. However, gender differences also emerged, with women proving to be less aggressive. A high number of passive answers were given across all the groups, suggesting that background experience could have influenced the participants' sense of efficacy in stressful situations. In the second study, a subsample of the participants were interviewed. The aim was to explore whether particular background experience coloured their perceptions of self and others, in situations of conflict. While nine out of the 10 Ag participants described incidents where they felt treated in a derogatory manner which could be linked to their disability, only two out of the nine NAg participants felt slighted in this fashion. Hence, a vulnerable sense of self could contribute to greater sensitivity in interpersonal situations, increasing the likelihood of an aggressive response. The clinical relevance of this work is discussed, alongside the possibilities for future research in this area.

Adolescent↗

Peptide T and glucose metabolism in AIDS dementia complex.

AIDS dementia complex (ADC) is the most common presenting neurologic manifestation of human immunodeficiency virus (HIV)-1 infection. We report FDG-PET studies in a 39-year-old man who had ADC and completed a 12-wk treatment protocol with 1.2 mg/day of intranasal peptide T, one before and one after 12 wk of treatment with peptide T. Peptide T is an octapeptide under investigation for treatment of ADC patients. Values of rCMRglc were converted to Z scores using the mean and standard deviation of values of rCMRglc in three HIV-seronegative matched controls, each of which was studied twice, at the beginning and end of a 12-wk interval. Thirty-five of 60 regions assayed showed Z scores with absolute values > or = 3 (considered abnormal) in the baseline study. Regions with high absolute values of Z scores were located in subcortical areas and in the limbic system, and to a lesser degree in the frontal, temporal and parietal lobes. Thirty-four of these 35 regions showed remission (decrease in the absolute values of Z scores) after treatment. Only one region showed no improvement in the second study. Three regions with absolute values of Z scores < 3 in the baseline study manifested Z scores with magnitudes > or = 3 in the second study. These preliminary observations suggest that functional neuroimaging techniques provide a useful tool in the evaluation of the response to treatment in ADC patients.

AIDS Dementia Complex↗

Calcitonin inhibits the phosphorylation of various proteins in rat brain synaptic membranes.

The present report examines the effect of different calcitonins and analogs on the in vitro phosphorylation of brain synaptic membrane proteins. The findings demonstrate that calcitonin is a potent inhibitor of several brain synaptic proteins and that salmon and eel calcitonins are considerably more potent than thyrocalcitonin in eliciting this effect. Deletion of leucine from position 16 in salmon calcitonin sequence resulted in a drastic loss of inhibitory activity, indicating the importance for a hydrophobic residue at position 16 in the intact calcitonin molecule. The mechanism of calcitonin inhibition of protein phosphorylation was likely due to the blockade of stimulation of protein kinases by calmodulin.

Animals↗

Characterization and autoradiographic distribution of the beta-adrenergic receptor in the rat lung.

An unexpected distribution of the beta-adrenergic receptor in the rat lung was revealed by an autoradiographic technique. [3H]-Dihydroalprenolol binding was stereoselective. L-propranolol was 300 times more potent than D-propranolol in competition experiments. Scatchard analysis revealed a Kd of 1.1 nM and Bmax of 14 fmol/mg wet weight. Relative potencies of beta-adrenergic ligands were: propranolol greater than alprenolol greater than timolol greater than pindolol greater than isoproterenol greater than epinephrine greater than soterenol greater than metoprolol greater than terbutaline greater than norepinephrine. The autoradiograms generated revealed a diffuse pattern with binding always associated with tissue structures. We conclude that beta-adrenergic receptors are extensively distributed in the lung, being present in large and small airways and blood vessels.

Animals↗

Interaction of bombesin and litorin with specific membrane receptors on pancreatic acinar cells.

We have prepared (125)I-labeled [Tyr(4)]bombesin and have examined the kinetics, stoichiometry, and chemical specificity with which the labeled peptide binds to dispersed acini from guinea pig pancreas. Binding of (125)I-labeled [Tyr(4)]-bombesin was saturable, temperature-dependent, and reversible and reflected interaction of the labeled peptide with a single class of binding sites on the plasma membrane of pancreatic acinar cells. Each acinar cell possessed approximately 5000 binding sites, and binding of the tracer to these sites could be inhibited by [Tyr(4)]bombesin [concentration for half-maximal effect (Kd), 2 nM], bombesin (Kd, 4 nM), or litorin (Kd, 40 nM) but not by eledoisin, physalemin, somatostatin, carbachol, atropine, secretin, vasocative intestinal peptide, neurotensin, or bovine pancreatic polypeptide. At high concentrations (>0.1 muM), cholecystokinin and caerulein each caused a small (15-20%) reduction in binding of lableled [Tyr(4)]bombesin. With bombesin, litorin, and [Tyr(4)]bombesin, there was a close correlation between the relative potency for inhibition of binding of labeled [Tyr(4)]bombesin and that for stimulation of amylase secretion. For a given peptide, however, a 10-fold higher concentration was required for half-maximal inhibition of binding than for half-maximal stimulation of amylase secretion, calcium outflux, or cyclic GMP accumulation. These results indicate that dispersed acini from guinea pig pancreas possess a single class of receptors that interact with [Tyr(4)]bombesin, bombesin, and litorin and that occupation of 25% of these receptors will cause a maximal biological response.

Amylases↗