Search

Computerized cognitive testing with software programs such as the Automated Neuropsychological Assessment Metrics (ANAM) have long been used to assess cognition in military samples. This study describes demographic influences on computerized testing performance in a large active duty military sample (n = 2366). Performance differences between men and women were minimal on most ANAM subtests, but there was a clear speed/accuracy trade-off, with men favoring speed and women favoring accuracy on the Continuous Performance Test (CPT) subtest. As expected, reaction time increased with age on most subtests, with the exception of Mathematical Processing Test (MTH). Higher education resulted in significant but minimal performance increases on Code Substitution (CDS), Matching to Sample (MSP), and Memory Search (STN) subtests. In contrast, substantial performance differences were seen between education groups on the MTH subtest. These data reveal that it is important to consider demographic factors, particularly age, when using ANAM to draw conclusions about military samples. These results also point to the importance of exploring demographic influences for all reaction time–based computerized assessment batteries.

To compare the efficacy and safety of rivastigmine (3 to 6 mg/day) vs placebo over 12 weeks in patients with traumatic brain injury and persistent cognitive impairment.

APOEhas been demonstrated to influence traumatic brain injury (TBI) outcome. The relationship between APOEgenotype and memory following TBI was examined in 110 participants in the Defense and Veterans’ Head Injury Program. Memory performance was worse in those who had an APOE4 allele (n 30) than those who did not (n 80), whereas genotype groups did not differ on demographic or injury variables or on measures of executive functioning. These data support a specific role for the APOE protein in memory outcome following TBI, and suggest an APOE isoform–specific effect on neuronal repair processes.

Turkey poults possessing maternally-derived antibody to Newcastle disease respond poorly, in terms of haemagglutination inhibiting (HAI) antibody response, to vaccination within the first 4 weeks of life. This unsatisfactory effect occurs both with live La Sota vaccine administered by intraocular/intranasal instillation or with killed oil emulsion adjuvant vaccine given by intramuscular injection. Re-vaccination of these birds with killed emulsion vaccine at 4 or 6-weeks-old indicates that they have become sensitised by either method of primary vaccination and results in the establishment within 4 weeks of high (8-9 log2) and prolonged HAI antibody levels. Further vaccination at 29-weeks-old raises the levels from 5 log2 to 10-11 log2.

Concurrent vaccination of one-day-old chicks with 2 x 105 50% embryo infectious doses of live B1 Newcastle disease virus and 0.25 ml killed oil emulsion Newcastle disease vaccine produced satisfactory levels of circulating haemagglutination inhibiting antibody although the recipient chicks possessed titres of maternally derived antibody as high as 10 log2. This effect was also seen when the chicks were given turkey herpesvirus for immunisation against Marek's disease. The satisfactory Newcastle disease antibody levels achieved by the vaccination programme did not fall below 5 log2 during the first 20 weeks of the birds' 40 week life span. Re-vaccination with live B1 vaccine at 17-days-old did not boost antibody levels, but re-vaccination with oil emulsion vaccine at 9 weeks-old produced a rise from 7 log2 to 11 log2. These findings are considered to be significant in establishing and maintaining immunity to Newcastle disease for both broilers and laying hens, particularly in areas where the disease is endemic.

We have previously demonstrated that the Na(+)-K+ pump on the basolateral membrane of the rabbit cortical collecting duct can function in the K+/K+ exchange mode. Increasing intracellular phosphate in red blood cells inhibits the Na+ pump and increases K+/K+ exchange. We found that maneuvers designed to increase intracellular phosphate in collecting duct cells caused an increase in K+/K+ exchange. Subjecting the cells to a metabolic insult (cyanide) increased K+/K+ exchange by the pump as judged by its ouabain sensitivity and lack of electrogenic or conductive characteristics. The results demonstrate that the rate of K+/K+ exchange by the Na(+)-K+ pump can be altered by changes in intracellular phosphate over a range that is physiologically or pathologically achievable. The results also suggest a mechanism for inhibition of vectorial Na+ transport during metabolic stress.

Knowledge stored in the human prefrontal cortex may exert control over more primitive behavioral reactions to environmental provocation. Therefore, following frontal lobe lesions, patients are more likely to use physical intimidation or verbal threats in potential or actual confrontational situations. To test this hypothesis, we examined the relationship between frontal lobe lesions and the presence of aggressive and violent behavior. Fifty-seven normal controls and 279 veterans, matched for age, education, and time in Vietnam, who had suffered penetrating head injuries during their service in Vietnam, were studied. Family observations and self-reports were collected using scales and questionnaires that assessed a range of aggressive and violent attitudes and behavior. Two Aggression/Violence Scale scores, based on observer ratings, were constructed. The results indicated that patients with frontal ventromedial lesions consistently demonstrated Aggression/Violence Scale scores significantly higher than controls and patients with lesions in other brain areas. Higher Aggression/Violence Scale scores were generally associated with verbal confrontations rather than physical assaults, which were less frequently reported. The presence of aggressive and violent behaviors was not associated with the total size of the lesion nor whether the patient had seizures, but was associated with a disruption of family activities. These findings support the hypothesis that ventromedial frontal lobe lesions increase the risk of aggressive and violent behavior.

Recent amendments to the law allow video recordings of initial interviews with children to be used as evidence in court. In order that children may benefit fully from this change it is crucial that these interviews are of as high a quality as possible and are conducted in a way that is acceptable to the courts. Recently published recommendations for interviewing advocate the use of general, open-ended questions wherever possible (Home Office, 1992) as this technique tends to result in accurate statements. However, recent research has shown that young children questioned in this way are unlikely to report all the relevant information they have. The present recommendations as they stand may in fact discriminate against the very children they are designed to help. This paper demonstrates that the present recommendations are not optimal for interviewing five to six-year-old children and suggests that the use of non-suggestive visual cues may be a way of increasing the overall quality of children's reports.

The uptake of 32P-labeled polyoma virus deoxyribonucleic acid (DNA) (I and II + III) by mouse embryo cells was increased from two- to fivefold in the presence of 500 µg of diethylaminoethyl-dextran (DEAE-D) per ml. This concentration of DEAE-D gives maximal enhancement of infectivity; however, the increase is many thousand-fold. As the DEAE-D concentration was increased from 0 µg/ml, uptake and infectivity increased to flat maxima and then decreased in a similar manner, except that at low DEAE-D concentrations uptake was relatively much greater than infectivity. Several other polycations also increased DNA uptake but did not enhance infectivity, and uptake of viral DNA was unaffected by the presence of mouse DNA, although infectivity was reduced. Thus, increased uptake is not the sole basis for the enhancement of infectivity produced by DEAE-D. The possibilities that DNA complexed with DEAE-D penetrates more rapidly or is stabilized against degradation do not completely account for enhancement since complexes formed in mixtures of DNA and DEAE-D, which sedimented heterogeneously from 40 to 60S, were infectious only for monolayers treated with DEAE-D. A more likely factor in enhancement is inhibition of the cellular nuclease activity detected, since virus DNA exposed to cells was much more degraded in the absence than in the presence of DEAE-D. The nuclease activity produced single-strand breaks in double-stranded DNA. Treatment of monolayers with deoxyribonuclease after adsorption of DNA in the presence of DEAE-D reduced cell-associated radioactivity by about 70%, although the number of plaques formed was not affected. In the absence of DEAE-D, 90 to 100% was removed by deoxyribonuclease. Thus, in both cases most of the DNA was adsorbed extracellularly. The greater deoxyribonuclease-resistant fraction in the presence of DEAE-D would be consistent with another possibility: that enhancement results from an increase in DNA penetration rate due to some action of DEAE-D on the cell.

A baseline computerized cognitive assessment was completed by 483 military cadets before their initial school year. Fourteen cadets concussed during physical education boxing were retested <1 hour after injury and again on return to full activity 4 days later. Compared with baseline testing, postinjury performance on simple reaction time and continuous performance tests was significantly slowed, even after cadets experienced resolution of physical symptoms and were cleared to resume full activity. These findings may be relevant to current concussion management guidelines.

ALTHOUGH the presence of defective mutants has been demonstrated in several animal virus systems1–3the isolation in a pure form of corresponding virions or viral nucleic acid molecules has not proved generally possible so far. It is important, however, for oncogenic virus systems to isolate such mutants to test the hypothesis that defective viruses, similar to or identical with those already recognized, are active in initiating oncogenic processes.