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M D Bell

Publications and source records attributed to M D Bell.

At least 37 records · Page 2Linked to original sources
PubMed1999

Personality and psychopathology in schizophrenia: the association between personality traits and symptoms.

Research has indicated that stable individual differences in personality exist among persons with schizophrenia, and that they likely predate the onset of illness. Little is known, however, about whether individual differences in personality are related to levels of psychopathology. This study tested the hypotheses that levels of Extroversion, Neuroticism, and Psychoticism are associated with symptomatology. Accordingly, measures of these dimensions of personality and of symptomatology were obtained simultaneously for 113 male subjects with schizophrenia or schizoaffective disorder. Next, subjects were characterized as having high or low levels on each personality dimension and their scores on the five components of the Positive Negative Syndrome Scale were compared using multivariate and univariate procedures. Results indicate that extroverted subjects had lower levels of Positive, Negative, and Emotional Discomfort symptoms, and higher levels of Excitement symptoms than introverted subjects. Subjects with higher levels of Neuroticism had higher levels of Positive and Emotional Discomfort symptoms than subjects with lower levels of Neuroticism. No differences in symptoms were found among subjects with higher versus lower levels of Psychoticism. Results suggest individual differences in personality are associated with psychopathology in schizophrenia and may help further explain the heterogeneity widely observed in this disorder.

Adaptation, Psychological↗
PubMed1999

Diffuse axonal injury in infants with nonaccidental craniocerebral trauma: enhanced detection by beta-amyloid precursor protein immunohistochemical staining.

OBJECTIVE: Accurate identification of diffuse axonal injury is important in the forensic investigation of infants who have died from traumatic brain injury. beta-Amyloid precursor protein (beta-APP) immunohistochemical staining is highly sensitive in identifying diffuse axonal injury. However, the effectiveness of this method in brain-injured infants has not been well established. The present study was undertaken to assess the utility of beta-APP immunohistochemistry in detecting diffuse axonal injury in infants with either shaken baby syndrome or blunt head trauma. MATERIALS AND METHODS: Archival formalin-fixed, paraffin-embedded blocks from infants (<1 year old) with shaken baby syndrome (7 cases) and blunt head trauma (3) and blocks from 7 control cases that included nontraumatic cerebral edema (1), acute hypoxic-ischemic encephalopathy (1), and normal brain (5) were immunostained for beta-APP. A semiquantitative assessment of the severity of axonal staining was made. Corresponding hematoxylin-eosin-stained sections were examined for the presence of axonal swellings. RESULTS: Immunostaining for beta-APP identified diffuse axonal injury in 5 of 7 infants with shaken baby syndrome and 2 of 3 infants with blunt head trauma. Immunoreactive axons were easily identified and were present in the majority of the sections examined. By contrast, hematoxylineosin staining revealed axonal swellings in only 3 of 7 infants with shaken baby syndrome and 1 of 3 infants with blunt head trauma. Most of these sections had few if any visible axonal swellings, which were often overlooked on initial review of the slides. No beta-APP immunoreactivity was observed in any of the 7 control cases. CONCLUSIONS: Immunostaining for beta-APP can easily and reliably identify diffuse axonal injury in infants younger than 1 year and is considerably more sensitive than routine hematoxylin-eosin staining. We recommend its use in the forensic evaluation of infants with fatal craniocerebral trauma.

Adult↗
PubMed1999

Chronic hypertension with subsequent congestive heart failure in a western lowland gorilla (Gorilla gorilla gorilla).

Chronic severe subclinical systemic hypertension was diagnosed in a 28-yr-old male western lowland gorilla (Gorilla gorilla gorilla). Thoracic radiography, electrocardiography, and echocardiography revealed an enlarged heart with a hypertrophied left ventricle, mitral regurgitation, and a persistent left bundle branch block. Enalapril, later combined with nifedipine, was of some value in reducing the hypertension, with partial reversal of cardiac enlargement and resolution of the bundle branch block. Two years after initiation of treatment, the gorilla developed lethargy and dyspnea. The diagnosis of heart failure was confirmed under anesthesia; the gorilla did not recover and was euthanized. Postmortem examination confirmed congestive heart failure with chronic, fibrosing cardiomyopathy similar to that in other gorillas.

Animals↗
PubMed1998

Personality and psychosocial dysfunction in schizophrenia: the association of extraversion and neuroticism to deficits in work performance.

Research on vocational dysfunction in schizophrenia has as yet only examined associated features of illness. We hypothesized that personality variables may be also associated with work function. We reasoned that higher levels of extraversion and neuroticism would predict poor function by virtue of the social support seeking and passive/avoidant coping styles associated with each. To test this, multiple regressions were conducted in which measures of extraversion and neuroticism predicted work performance among 43 subjects with schizophrenia or schizoaffective disorder. Higher levels of extraversion and neuroticism significantly predicted poorer function, accounting for between 7% and 27% of the variance in global cooperativeness, work quality, work habits and personal presentation measures of work behavior. The potential importance of assessing personality in rehabilitation is discussed.

Adult↗
PubMed1998

Insight and interpersonal function in schizophrenia.

Research has linked impaired insight in schizophrenia to poorer medication compliance and treatment outcome. It is unclear, however, whether poorer interpersonal function is also associated with impaired insight. To examine this question, subjects with schizophrenia or schizoaffective disorder were classified as having unimpaired (N = 44) or impaired (N = 57) insight, and their scores on Heinrichs et al.'s Quality of Life (QOL) Scale were compared. Multiple regressions were conducted to determine the relationship between individual components and social function. Results indicate that subjects with impaired insight had significantly poorer QOL interpersonal relation and intrapsychic foundation scores than unimpaired subjects, despite having equivalent deficit symptoms. Unawareness of the social consequences of illness was found to be the component of insight more closely linked to social dysfunction. This suggests that impairments in insight may be uniquely associated with social dysfunction.

Adult↗
PubMed1998

The functional consequences of memory impairments on initial work performance in people with schizophrenia.

Exploring the link between cognitive impairments and domains of function is a new trend in schizophrenia research. This study reports on the association of verbal memory impairment and initial work function for a group of 87 individuals diagnosed with either schizophrenia or schizoaffective disorder. Multiple regression analyses were used to predict the degree of association between verbal memory variables and ratings on the Work Behavior Inventory (WBI) in the initial week of a vocational rehabilitation program. Results indicated that verbal memory scores predicted 20% of the WBI total score. Results also indicated strong relationships with the individual work domains of work habits and work quality and weaker relationships with the domains of cooperativeness and personal presentation. No significant relationship was found between verbal memory variables and social skills at the job site. Verbal memory impairment is discussed as a rate limiting factor in rehabilitation.

Adult↗
PubMed1998

Neurocognitive function and insight in schizophrenia: support for an association with impairments in executive function but not with impairments in global function.

It remains unclear how impaired insight and neurocognitive impairment are related to one another in schizophrenia. In order to examine this relationship, subjects with schizophrenia or schizoaffective disorder were classified as having 'impaired' (n=38) or 'unimpaired' (n=43) insight based on their insight rating on the Positive and Negative Syndrome Scale (PANSS). Their performance on neuropsychological tests of global function, executive function, memory and vigilance was then compared. Multivariate analyses followed by Scheffe tests indicated that subjects with impaired insight performed less well on the Wisconsin Card Sorting Test, demonstrating poorer abstract flexibility and heightened perseveration. No differences were found between the groups with regard to global cognitive function, memory or vigilance. This suggests that insight is closely linked to deficits in executive function, and that it may be associated with the compromise of frontal lobe function.

Adult↗
PubMed1997

Wisconsin Card Sorting Test dimensions in schizophrenia: factorial, predictive, and divergent validity.

This study explored the factor structure of the Wisconsin Card Sorting Test (WCST). Scores from 197 participants with schizophrenia or schizoaffective disorder were subjected to an exploratory factor analysis that yielded three factors: Perseveration, Nonperseverative Error, and Inefficient Sorting. Comparison with two previous factor analyses revealed remarkable factorial invariance. Correlations with subject and illness characteristics, symptom dimensions, and work performance demonstrated predictive and divergent validity for the three factors. However, a representative item from each factor yielded similar correlations with very little loss of power suggesting that the factors are composed of highly redundant items. When data reduction is necessary, schizophrenia researchers are justified in using three variables: perseverative error, nonperseverative error, and failure to maintain set, to represent WCST performance.

Adult↗
PubMed1997

Clinical benefits of paid work activity in schizophrenia: 1-year followup.

In a previous article in the Schizophrenia Bulletin (Vol. 22, No. 1, 1996), we presented findings of a study on the clinical and rehabilitative effects of work activity on 150 subjects diagnosed with schizophrenia or schizoaffective disorder. Subjects were randomly assigned to either a Pay ($3.40/hr) or No-Pay group and given 6-month work placements in a Department of Veterans Affairs medical center. At the 5-month followup, Pay subjects had worked more hours and earned more money (from any employment) than No-Pay subjects. Pay subjects also had significantly greater improvement in symptoms and lower rehospitalization rates. Clinical improvement was closely linked to amount of participation. We concluded that pay increased participation. The current study examined clinical and rehabilitative outcomes at 1-year followup, 6 months after the conclusion of the work program. Results indicated that the Pay subjects had a significant decrease in work activity once they had completed the work program. However, 75 percent of those who had fully participated in the program continued working during the subsequent 6 months, either as volunteers or for pay. Clinical outcomes for subjects in the Pay condition were attenuated at 1-year followup but still significantly better than for subjects in the No-Pay condition. More than 40 percent of participants continued to be "much improved" on total symptoms, and more than 50 percent were "much improved" on positive symptoms. Discussion focuses on the importance and limitations of work for pay as a clinical intervention and concludes that continuous work services are necessary and beneficial for many people with schizophrenia.

Adult↗
PubMed1997

Cognitive impairment and substance abuse history as predictors of the temporal stability of negative symptoms in schizophrenia.

Research has not consistently indicated that negative symptoms in schizophrenia are temporally stable. One possible explanation for this is that stable negative symptoms are a characteristic of only some individuals with schizophrenia. The current study explored whether cognitive impairment and stimulant abuse history were associated with amount of change in negative symptom level over a 1-year period. Results indicated that among 72 subjects with schizophrenia, performance on the Wisconsin Card Sorting Test and history of stimulant abuse significantly accounted for 18% of the variance in symptom variability after age, intelligence quotient, and initial symptom severity were controlled. As hypothesized, poorer performance on the Wisconsin Carding Sorting Test was associated with less symptom variability, whereas a more extensive stimulant abuse history was associated with greater variability. A discriminant function analysis was able to correctly classify 96% of subjects as having stable symptoms but only 30% as having unstable symptoms indicating a sensitive, but not specific, classification. This finding suggests that cognitive deficits may be a necessary but insufficient condition for temporal stability of negative symptoms and that negative symptoms in schizophrenia are a complex phenomenon best understood in the context of other features of illness and psychosocial variables.

Adult↗
PubMed1996

Overriding the brain's intrinsic resistance to leukocyte recruitment with intraparenchymal injections of recombinant chemokines.

Following the intracranial injection of lipopolysaccharide or during acute neuronal degeneration, there is a paucity of polymorphonuclear leukocyte recruitment to the brain parenchyma and a delay in monocyte recruitment. The present study investigates whether the injection of specific leukocyte chemoattractants into the murine central nervous system can override this intrinsic resistance. Recombinant alpha-(IL-8/NAP-1 MIP-2, IP-10) and beta-chemokines (MCP-1, RANTES) were injected into the murine hippocampus and leukocyte recruitment was assessed histologically. Injections were also made into the dermis of the hind flank for comparison. At doses of 1 microgram, MCP-1 was found to be the most potent monocyte chemoattractant in the brain parenchyma and skin with IP-10 and RANTES producing minimal monocyte recruitment to both sites. In contrast IL-8, and MIP-2 provoked dramatic polymorphonuclear leukocyte recruitment in both the central nervous system and skin. The polymorphonuclear leukocyte recruitment was associated with a breaching of the blood brain barrier that was particularly severe after MIP-2. Both L-8 and MIP-2 induced blood brain barrier breakdown could be attenuated by prior depletion of the circulating leukocytes. The regulation of polymorphonuclear leukocyte chemoattractants in the brain parenchyma during injury and infection is an important area for future studies.

Animals↗
PubMed1996

Clinical benefits of paid work activity in schizophrenia.

Although indirect support can be found for the clinical benefits of work, it has not been studied in randomized designs, nor have critical variables been manipulated. One such variable is pay incentive. The authors present a study of 150 subjects with schizophrenia or schizoaffective disorder who were randomized into Pay ($3.40/hour) and No-Pay conditions and offered 6-month work placements within a Department of Veterans Affairs medical center. Subjects participated in a work-related support group and were evaluated weekly on symptom measures. Results indicated that Pay subjects worked more hours and earned more money than No-Pay subjects. Pay subjects showed more total symptom improvement at followup, and more improvement, particularly on positive and emotional discomfort symptoms. They also had a significant lower rate of rehospitalization than No-Pay subjects. Participation in work activity was closely associated with symptom improvement. Participators showed more total symptom improvement at followup than partial participators or nonparticipators, and more improvement, particularly on positive, hostility, and emotional discomfort symptoms. We concluded that pay increased participation and that, in this study, participation in work activity was primarily responsible for symptom reduction.

Adult↗
PubMed1996

Homicide in homosexual victims: a study of 67 cases from the Broward County, Florida, Medical Examiner's office (1982-1992), with special emphasis on "overkill".

Forensic pathologists often state that homosexual homicides are more violent than those with heterosexual victims. Overkill or wounding far beyond that required to cause death is a frequently used descriptor of these deaths. We quantified the number and extent of injuries between homosexual and heterosexual homicide victims to determine whether one group suffered more violence than the other. This case-control study involved 67 homosexual homicide victims and 195 age, race, and gender-matched heterosexual (control) homicide victims from the Broward County Medical Examiner's Office in Fort Lauderdale, Florida, between 1982 and 1992. The sexual preference of the victims was determined by police and medical examiner investigation. We compared the percentage of cases with multiple causes of death, mean number of injuries/case, and the mean number of different body sites with injuries/case between the two groups. The percentage of cases with multiple causes was 12% (n = 8) and 5% (n = 10) in the homosexual and heterosexual victims, respectively, with no significant statistical difference detected (Fisher exact test, two-tail, p = 0.088). The mean number of fatal sharp (5.4 vs 3.3, p < 0.05), blunt (9.0 vs 6.5, p < 0.05), and total (14.5 vs 6.5, p < 0.001) injuries/case was greater among the homosexual victims than among the heterosexual group. These differences were all statistically significant using the Mann-Whitney rank sum test. The mean number of different body sites with injuries/case was also greater (3.5 vs 2.4, p < 0.001) among the homosexual victims than among the heterosexual group. This difference was statistically significant using the Mann-Whitney rank sum test. Homosexual homicides are more violent than heterosexual homicides when one compares the mean number of injuries (fatal sharp, blunt, and total)/case and the extent of injuries on the body. The mean number of stab wounds wounds/case and percentage of cases with multiple causes of death were also greater among the homosexual group, but the differences were not statistically significant.

Adult↗