Biomedical subjects

Peter W Schofield

Publications and source records attributed to Peter W Schofield.

5 recordsLinked to original sources

PubMed2006

Neuropsychological health in F-111 aircraft maintenance workers.

OBJECTIVE: To contrast subjective and objective measures of neuropsychological health in F-111 aircraft Deseal/Reseal maintenance personnel, against two appropriate comparison groups. METHODS: Exposed and comparison participants completed a postal questionnaire which included a validated memory questionnaire and additional questions relating to possible cognitive symptoms. They also underwent a comprehensive neuropsychological assessment and screening for a past or current disturbance of mood. Multiple linear or logistic regression was conducted for each outcome using exposure group and potential confounders as explanatory variables. RESULTS: There was a strong and consistent excess of self-reported cognitive problems among the exposed group relative to the comparison groups including a 2.8-4.3-fold increase in self-reported symptoms of forgetfulness, loss of concentration and difficulty finding the right word. On detailed neuropsychological testing, the exposed group performed significantly worse than comparisons on tests of psychomotor speed, executive functioning, and new learning/memory. These findings could not be accounted for by disturbances of mood or other potential confounders. CONCLUSIONS: There was a strong and consistent increase in self-reported cognitive problems among the exposed, and small but significant exposure-specific differences on objective tests of cognitive functioning. The findings are consistent with the development of adverse neuropsychiatric changes related to occupational exposure to solvents.

Adult↗

PubMed2006

Traumatic brain injury among Australian prisoners: rates, recurrence and sequelae.

PRIMARY OBJECTIVE: To establish the prevalence, severity, recurrence and sequelae of past traumatic brain injury (TBI) among individuals recently received into custody. RESEARCH DESIGN: Cross-sectional random sample of men recently received into the New South Wales' (NSW) criminal justice system. PROCEDURES: Participants were screened for a history of TBI including the injury setting, severity, treatment and sequelae of up to five separate TBI episodes. OUTCOMES AND RESULTS: Of 200 study participants, 82% endorsed a history of at least one TBI of any severity and 65% a history of TBI with a loss of consciousness (LOC). Multiple past TBIs were common, as were ongoing sequelae. Treatment for the TBI was more common among those TBIs with a LOC compared with no LOC (66% vs. 39%). CONCLUSIONS: Among individuals entering the criminal justice system, past TBI is common and often associated with ongoing neuropsychiatric and social sequelae. Screening for TBI at the point of reception may be warranted to better understand and treat those with ongoing neuropsychiatric sequelae arising from the TBI.

Adolescent↗

PubMed2006

Mental health in F-111 maintenance workers: the study of Health Outcomes in Aircraft Maintenance Personnel (SHOAMP) general health and medical study.

OBJECTIVE: We sought to contrast mood disorder symptoms in F-111 aircraft Deseal/Reseal maintenance personnel with appropriate comparisons. METHODS: Participants completed a comprehensive health assessment, including measures of mood disorder, self-reported mood symptom questionnaire items, and review of anxiolytic and depression medication. Multiple logistic regression was conducted for each outcome using exposure group and potential confounders as explanatory variables. RESULTS: There was high agreement between self-reported mood disturbance and objective tests. The exposed group was more likely to self-report previous diagnoses of depression/anxiety, had higher use of antidepressant medications, and had increased risk of diagnosis of depression/anxiety. Results were consistently strong against both comparison groups, with the exposed more likely to have mental distress and social dysfunction when compared with the Australian population. CONCLUSIONS: There is robust evidence for an association between F-111 Deseal/Reseal exposure and impaired mental health.

Aircraft↗

PubMed2003

Cognitive screening using a tape recorder: a pilot study.

OBJECTIVES: To determine whether a tape recorder can be used to administer cognitive tests efficiently and yield valid results. DESIGN: Convenience sample. Administration of cognitive test materials by tape recorder and conventional technique. SETTING: Outpatient clinic. PARTICIPANTS: Subjects from memory disorder clinic, hostel accommodation, and community. MEASUREMENTS: Responses to Hopkins Verbal Learning Test-revised, verbal fluency items from the controlled oral word association test, 10-item naming task, a construction task, and speed writing task. RESULTS: Performances on the tape- and clinician-administered battery of tests were highly correlated. Memory impairment was accurately detected using the tape battery. Data from 30 minutes of testing via tape were obtained at the cost to the clinician of 2 to 3 minutes of scoring time. CONCLUSION: Tape-administration of cognitive test material warrants further study as an efficient means of cognitive screening.

Adult↗

PubMed2003

Mutations in the tau gene that cause an increase in three repeat tau and frontotemporal dementia.

The majority of cases with frontotemporal dementia (FTD) have no tau deposition in the brain, yet mutations in the tau gene lead to a similar clinical phenotype with insoluble tau depositing in neuropathological lesions. We report two tau gene mutations at positions +19 and +29, in the intronic sequences immediately following the stem loop structure in exon 10, which segregate with FTD. Exon-trapping experiments showed that these gene mutations alter the splicing out of exon 10 and produce an increase in tau isoforms with three microtubule binding domains (three repeat tau). Mutagenesis experiments demonstrated that the +19 mutation was responsible for the increase in three repeat tau, possibly by altering an intron silencer modulator sequence element found at this region of the gene. Microtubule binding experiments revealed a significant decrease in microtubule assembly with increasing amounts of three and decreasing amounts of four repeat tau. Brain autopsy was available in one case. Analysis of the type of soluble tau isoforms revealed an increase in three repeat tau and an absence of tau isoforms with exon 3 inserts. No insoluble tau was isolated in the tissue fractions, consistent with the absence of tau-positive histopathology. There was also an increase in tau degradation products suggestive of increased proteolysis. This increase in tau breakdown products was associated with TUNEL- and activated caspase-3-positive neurons identified histologically. These studies show that increases in soluble three repeat tau can be responsible for FTD in cases with tau gene mutations in the intronic region immediately adjacent to the stem loop in exon 10. These cases of FTD have tau isoforms (without exon 3 inserts) that do not form abnormal aggregates and appear more prone to proteolysis. The increase in tau proteolysis was associated with increased evidence of apoptosis. This mechanism of neurodegeneration may be more applicable to the majority of FTD cases, which do not accumulate insoluble tau deposits.

Alternative Splicing↗