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J H Dowson

Publications and source records attributed to J H Dowson.

11 recordsLinked to original sources
PubMed1992

The morphology of lipopigment in rat Purkinje neurons after chronic acetyl-L-carnitine administration: a reduction in aging-related changes.

The aging-related accumulation of neuronal lipopigment is considered to be cellular debris from processes of renewal of cellular constituents, but it can also reflect cell damage and certain diseases. Acetyl-L-carnitine (AC) has been reported to reduce some morphological and behavioral associations of brain aging and the present study investigated the effects of 37 weeks of AC administration on lipopigment in rat Purkinje neurons. Lipopigment was identified by fluorescence microscopy and the area enclosed by an outline of each discrete region of lipopigment was measured. Acetyl-L-carnitine was associated with a significant (p = 0.05) reduction in the number of discrete lipopigment regions and there was a significant (p = 0.001) association of AC administration with numbers of lipopigment regions in various size categories. As AC administration was associated with a reduction in some of the aging-related morphological changes in lipopigment, this compound is a candidate for evaluation as a long-term prophylactic agent for the adverse effects of cerebral aging.

Acetylcarnitine↗
PubMed1992

Lipopigment in rat hippocampal and Purkinje neurones after chronic phenytoin administration.

The accumulation of lipopigment may indicate ageing, certain diseases and cellular damage, while phenytoin, which has been claimed to cause selective clinical cerebellar dysfunction and degeneration, has been reported to produce increased lipopigment accumulation in rat Purkinje neurones. In the present study, 8 rats received phenytoin, 300 mg/kg/day for 20 weeks, and were compared with a control group of 9 rats in respect of lipopigment in Purkinje and hippocampal neurones. Neuronal lipopigment was identified by fluorescence microscopy. The results did not indicate that phenytoin administration was associated with an increase in the area corresponding to (i.e. within the outlines of) neuronal lipopigment in Purkinje neurones, although the relatively small number of animals limits the power of the study. However, in hippocampal neurones, a two-way analysis of variance for numbers of discrete regions of lipopigment demonstrated a significant interaction (P = 0.003) between, firstly, size categories of discrete regions of lipopigment and, secondly, phenytoin administration or a control procedure. In hippocampal neurones, phenytoin administration was accompanied by a decrease in the numbers of discrete lipopigment regions in the smaller size categories and an increase in the numbers in the larger size categories. This finding indicates the need for further investigation into the effects of phenytoin on brain regions other than the cerebellum, as intellectual deterioration may be related to chronic use of this drug.

Aging↗
PubMed1992

Associations between self-induced vomiting and personality disorder in patients with a history of anorexia nervosa.

Fifty-five patients of an eating disorders service with a history of anorexia nervosa (AN), defined by a history of refusal to maintain body weight above a level of 15% below that expected, completed a modified version of the revised Personality Diagnostic Questionnaire (PDQ-R) based on DSM-III-R personality disorders (PD). The subjects were divided into 2 groups based on AN subtypes: vomiters, defined by a history of self-induced vomiting, and non-vomiters, who had maintained low weight mainly or only by diet +/- excessive exercise. Vomiters showed significantly higher scores on self-report measures of borderline and antisocial PD criteria. Discriminant analysis based on PD scores for all 13 DSM-III-R PD categories correctly predicted AN subtype membership based on vomiting history in 85.5% of patients. The implications of PD comorbidity for the development and management of eating disorders are discussed.

Adolescent↗
PubMed1992

Assessment of DSM-III-R personality disorders by self-report questionnaire: the role of informants and a screening test for co-morbid personality disorders (STCPD)

A modified version of the revised Personality Diagnostic Questionnaire (PDQ-R), based on DSM-III-R personality disorders (PDs), was completed by 60 psychiatric patients. An informant's version was also completed by 60 relatives or friends nominated by each subject. Discrete DSM-III-R PDs were rare; the mean number of PDs per subject was 4.5. Cluster analysis showed that only antisocial PD was a basis for classification of patients, while most patients formed two groups which were mainly distinguished by quantitative differences related to the total scores of positive PD criteria. A shorter version of the questionnaire can be used as a screening test for co-morbid PDs (STCPD) which can predict the number of co-morbid DSM-III-R PDs. The total scores of positive PD criteria from the STCPD were usually (and significantly) higher than the corresponding scores from informants' questionnaires, but when an informant's total score exceeded that of the patient, this indicated a subject's under-reporting.

Adult↗
PubMed1991

Factor structure of DSM-III-R personality disorders shown by self-report questionnaire: implications for classifying and assessing personality disorders.

A modified version of the revised Personality Diagnostic Questionnaire (PDQ-R), based on DSM-III-R personality disorders (PD), was completed by 74 psychiatric patients. A factor analysis of the scores for each of the PD (i.e. of the number of positive DSM-III-R criteria for each of the PD) yielded 3 factors that defined 3 PD clusters. These were similar to the 3 DMS-III-R PD clusters for 7 of the 11 PD categories. The 3-group solution of a cluster analysis of the patients (using their scores of positive criteria for each of the PD) did not reflect these factors; the main discriminating variable between the 3 groups of patients was the total number of positive PD criteria. It is suggested that, for the routine assessment of patients, the most important derivative of the DSM-III-R classification of PD is the total score of positive PD criteria.

Adult↗
PubMed1977

The phenomenology of severe obsessive-compulsive neurosis.

The case histories are examined of 41 patients who were admitted to hospital for the first time with a diagnosis of obsessive-compulsive neurosis. Aspects of the phenomenology are reported which presented between the first appearance of obsessive-compulsive symptoms and discharge from the first admission. The mean age for admission was 31-6 years (SD 14-3) and 68 per cent of the sample were women. The women showed significantly higher incidences of contamination phobia and of compulsive cleaning behaviour than did the men. Cleaning behaviour and avoidance of feared stimuli were the most frequently encountered manifestations of compulsive behaviour.

Adult↗
PubMedDate not supplied

DSM-III-R narcissistic personality disorder evaluated by patients' and informants' self-report questionnaires: relationships with other personality disorders and a sense of entitlement as an indicator of narcissism.

Modified versions of the revised Personality Diagnostic Questionnaire (PDQ-R) for DSM-III-R personality disorders (PDs) were completed by 60 patients and their informants. Patients' ratings gave a mean number of 4.5 PDs per subject and narcissistic (NAR) PD in 42%. Informants' ratings gave NAR PD in 38%. For patients and informants, NAR PD scores (i.e., the number of positive NAR PD criteria for each subject) were significantly correlated with histrionic (HIS) and borderline (BOR) PD scores and with scores of some PDs outside DSM-III-R's "cluster B." Also, there were significant correlations between patients' and informants' NAR PD scores and between NAR PD scores and total number of positive criteria (i.e., for all 13 PDs) for patients and informants. For patients' ratings, there were significant associations between NAR PD and HIS, BOR, and passive-aggressive (PAG) PDs and, for informants' ratings, between NAR and HIS PDs. There was no significant association between patients' and informants' diagnoses of NAR PD. Grandiosity, the most characteristic feature of narcissism, is related to NAR PD criteria 3 through 6. The patients' evaluation of criterion 6 (i.e., "Has a sense of entitlement ...") shows satisfactory item-total correlation and endorsement frequency, together with "fair to good" reliability when patients' and informants' ratings are compared (kappa = 0.62). The identification of a sense of entitlement by the patient may be a relatively reliable and valid indicator of narcissism.

Adult↗
PubMedDate not supplied

Changes in intraneuronal lipopigment in Alzheimer's disease.

Brains were examined from 22 patients with Alzheimer's disease (AD) (mean age 80.5, S.D. 11.5) and were compared with brains from 20 nondiseased subjects (mean age 81.1, S.D. 10.2). Intraneuronal lipopigment in all layers of a region of the superior frontal cortex was identified by fluorescence microscopy. The areas enclosed by the outlines of discrete regions of lipopigment autofluorescence were measured and assigned to a range of size categories. AD was associated with significant (p less than 0.05) decreases in the mean number (per neuron) of discrete regions of yellow lipopigment autofluorescence in the three smallest size categories and a significant increase in one of the larger size categories. Also, AD was associated with a significant decrease in the mean number (per neuron) of discrete regions of lipopigment autofluorescence (p less than 0.001). Significant (p less than 0.05) correlations were obtained between the Blessed dementia score (obtained within 2 years of death) and these lipopigment variables. The changes in neuronal lipopigment in AD may reflect an increased rate of lipopigment formation related to membrane and lysosomal abnormalities.

Aged↗