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Correlation of magnetic resonance imaging with neuropsychological testing in multiple sclerosis.

Previous research has suggested that cerebral lesions observed on magnetic resonance imaging (MRI) of MS patients are clinically "silent." We examined the validity of this assertion by correlating neuropsychological test performance with MRI findings in 53 MS patients. We used a semiautomated quantitation system to measure three MRI variables: total lesion area (TLA), ventricular-brain ratio (VBR), and size of the corpus callosum (SCC). Stepwise multiple regression analyses indicated that TLA was a robust predictor of cognitive dysfunction, particularly for measures of recent memory, abstract/conceptual reasoning, language, and visuospatial problem solving. SCC predicted test performance on measures on mental processing speed and rapid problem solving, while VBR did not independently predict cognitive test findings. These findings suggest that cerebral lesions in MS produce cognitive dysfunction and that MRI may be a useful predictor of cognitive dysfunction.

Brain

Signs of cognitive change in HIV disease: an event-related brain potential study.

We recorded event-related brain potentials (ERPs) from 2 groups of human immunodeficiency virus (HIV)-positive men with no physical illness or neurologic involvement: 9 asymptomatic (AS+) and 9 classified as having either acquired immunodeficiency syndrome (AIDS; 7) or AIDS-related complex (ARC; 2). In separate choice reaction time tasks, the subjects pressed buttons to randomly presented auditory or visual stimuli at probabilities of either 20/80 or 50/50. There were no group differences on any of the neuropsychological tests commonly used in screening batteries for HIV patients. In contrast, reduced P300 amplitudes and increased P300 latencies occurred in ARC/AIDS patients in response to both auditory and visual stimuli, while in AS+ patients such alterations occurred only in the visual modality. Significant delays in P2 latency were found only in the auditory modality and then only in ARC/AIDS patients. ARC/AIDS patients alone showed delayed response times, and only in the auditory modality. The P300 results demonstrate alterations in stimulus evaluation and processing speed in the earliest stages of HIV disease, even before cognitive deficits can be detected by more traditional measures.

AIDS-Related Complex

Molecular and prospective phenotypic characterization of a pedigree with familial Alzheimer's disease and a missense mutation in codon 717 of the beta-amyloid precursor protein gene.

We present prospective clinical and neuropathologic details of a pedigree segregating familial Alzheimer's disease (FAD) associated with a mutation (G----A substitution) at nucleotide 2149 in exon 17 of the amyloid precursor protein (APP) gene. This mutation, which is predicted to cause the missense substitution of isoleucine for valine at codon 717 of APP, cosegregated perfectly with the FAD trait (lod score = 3.49 at theta = 0.00). The earliest clinical manifestations of the disease relate to deficits in memory function, cognitive processing speed, and attention to complex cognitive sets. These changes occurred in the absence of changes in nonmemory language and visuospatial functions. The neuropathologic features of FAD associated with the APP717 mutation in this family include severe neuronal loss, abundant neurofibrillary tangles, amyloid plaques, and amyloid angiopathy. These results provide independent confirmation that mutations in the APP gene are linked to the FAD trait in some families.

Adult

Multifactorial assessment of reading disability: identifying the best predictors.

A multifactorial diagnostic assessment battery was evaluated using data obtained from 105 reading-disabled children and their matched controls (total N = 210). A stepwise discriminant function analysis selected five nonreading measures from among 16 as the best diagnostic predictors of reading disability. These measures included WISC-R Information and Digit Span, self-reported family histories of reading problems, and tests of symbol-processing speed and letter fluency.

Adolescent

Functional asymmetry for facial affect perception in high and low hostile men and women.

The influence of cerebral asymmetry in the perception of affect on Type A behaviour was examined. Twenty-five men and 25 women classified as Type A or Type B, using the Framingham Type A Scale (FTAS) and the Cook-Medley Hostility Inventory (CMHO), participated. Subjects were required to identify the facial affect depicted in Ekman and Friesen's (1978) angry, happy, and neutral stimuli using a forced-choice reaction-time paradigm with only angry or happy alternatives signified by the respective response manipulanda. Stimuli were presented within the left or right visual fields tachistoscopically. The results showed faster affect perception by right hemisphere (LVF), hemispheric differences related to affective valence, and sex differences in affect asymmetry. Type A and Type B groups differed in the forced identification of neutral stimuli revealing affective bias but not processing speed differences on this perceptual task.

Adolescent

An electron microscopic study of the vascular factor in hemorrhagic diathesis.

Experimental diapedetic hemorrhage (oozing) was produced by streptokinase in rabbits and the fine structures of mesenterial microvessels were observed. Diapedesis of erythrocytes was seen in the venular side of microcirculation. On the contrary, no diapedesis was seen in true capillary on the arteriolar side. Sticking of erythrocytes to venular wall prior to diapedesis was proved, electron microscopically, to be the state in which red blood cells were trapped in the gaps on the endothelial junction. It was considered to be the morphological findings of the prediapedetic state. Erythrocytes passed through gaps on the endothelial junctions with high plasticities under any diapedetic conditions mentioned above. Furthermore, in author's experiments by ruthenium red staining, erythrocytes were observed just passing through the basement membrane under electron microscopy, in spite of its high speed process. It was found that the basement membrane is a very important barrier in erythrocyte diapedesis.

Animals

A system for rapid analysis of long-term recordings of heart rate and other physiological parameters.

Using miniature cassette tape recorders, measurement of ECG and other physiological measures is possible in industrial or working situations. The development of a semi-automatic high speed processing system for analysis of the tape recorded data is described. This system decodes the signals on the tape, converts ECG to heart rate and presents a listing of the heart rate variation over the recording period, which may be up to 24 hours. A punched paper tape copy of the listing is used for input into a mainframe computer for subsequent analysis. The recorders and processing system have been used extensively for three years on a study of industrial work stress, and have proved reliable, accurate, and of sufficient sensitivity for in-depth analysis. They allow considerable data to be collected, permitting the thorough statistical analysis necessary for the interpretation of complex physiological responses.

Computers

[Paced addition. A neuropsychological test for assessment of divided attention].

The Pasat (Paced auditory serial addition task) is a test requiring addition of simple digits presented auditorily in several series of a successively higher pace of presentation. The task reflects the capacity for divided attention, is a measure of information processing speed and has appeared to be sensitive to minor attention deficits. We made a Dutch version characterized by longer time intervals between digits, for use in a study among (altogether 130) middle-aged and elderly persons. This modified version was evaluated with respect to feasibility. It appeared to be fairly feasible, provided sufficient opportunity for practice is given. Two series with inter-stimulus intervals of 4 and 3 seconds respectively were then evaluated with respect to validity and reliability in subjects of 48 to 74 years. Both Pasat series correlated well with two tests of attention: Digit Symbol (WAIS) and d2-test (r = 0.53-0.67), the relation with reaction decision speed being generally weak (r = 0.29-0.33) and weak to absent with a number of memory tests (r = -0.04-0.29). The Pasat performance shows a positive relationship with educational level and intelligence (inter-stimulus interval 4 seconds: r = 0.28 and 0.33 resp.; inter-stimulus interval 3 seconds: r = 0.40, 0.57 resp.). The stability of test performance over a period of about two months is moderate (r = 0.54, 0.61 resp.). In view of the excellent inter-observer reliability (r = 0.99) and the good parallel-test reliability (r = 0.79, 0.68 resp.), this might be explained by fluctuations in the capacity measured, rather than measurement error.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged

Antiepileptic drugs and memory.

Assessing the effects of medication on cognitive functions including memory is fraught with methodological problems. This article illustrates the range of approaches that have been employed. Medication effects have been more readily demonstrated in patients with intractable epilepsy, in whom drug dosages are higher and the risk of polytherapy is greater. Newly diagnosed cases and individuals treated with monotherapy show fewer effects. Evaluation of memory functions in most studies has been very limited, and where effects have been recorded these may well be secondary to changes in attentional level or mental processing speed.

Animals

[Prospective follow-up of neuropsychological deficits after cervicocephalic acceleration trauma].

30 patients with acute cervico-cephalic syndrome following whiplash injury (neck and head pain, vegetative symptoms and subjective complaints of impaired mental functions) without neurological deficits were investigated in a prospective follow-up of 3 months with neuropsychological examination in the acute phase (x = 5.7 days) and again 6 and 12 weeks after the accident. Attention, concentration, cognition and verbal and visual memory functions were quantified by neuropsychological tests, and changes over the observation period were analysed. In the acute phase all neuropsychological functions were below the individual's normal level. Deficits in attention and concentration recovered within the first 6 weeks. Further recovery within the following 6 weeks were observed in visual memory, imagination and analytic capacity. The capability of verbal memory and abstraction, cognitive selectivity and information processing speed was impaired for a longer time and first recovered after 12 weeks. In conclusion, intraindividual neuropsychological deficits following whiplash injury can be quantified and monitored to show the time course of recovery. Thus in clinical and forensic practice the diagnosis of a pseudoneurasthenic or even "neurotic" syndrome in acute whiplash injury should be made with caution.

Accidents, Traffic

Neurobehavioral recovery.

This review discusses recent programs in early and late neurobehavioral recovery from closed head injury (CHI). The research on early recovery has encompassed the relationship of localized brain lesions to the duration of impaired consciousness and features of posttraumatic amnesia. Of the research on late neurobehavioral outcome of CHI, studies emanating from the Traumatic Coma Data Bank are reviewed in detail, including analysis of acute neurologic indices in relation to recovery of memory, information processing speed, and other cognitive measures. Recent studies concerning the neurobehavioral outcome of CHI in children are discussed as are investigations of behavioral disturbance, psychosocial outcome, and family variables. The review concludes with an assessment of recent studies concerning the efficacy of rehabilitation directed toward the cognitive sequelae of CHI and preliminary trials to evaluate the potential use of psychoactive drugs in the postacute management of head injured patients.

Amnesia

[The dental profession in The Netherlands before 1865].

The dental profession before 1865 has been described with the help of sources from the 19th century, in combination with prosopographical research. During this period, dentists had no exclusive rights in dentistry: other surgical professions were also involved both with its theory and practice. Their specialised colleagues comprised a group of 137 dentists, largely related to a few Jewish families. This characteristic, underlined by their intensive migration and training within the family, had been responsible for the divergent position of the dentists in Dutch medical legislature of the 19th century. While in the medical profession the organisation and structure (1865) was the first te be revised, followed by a reorganisation of education (1876); in dentistry the recruitment and education had to be reformed (1865-1876) before the building up of a new professional structure. This process speeded up by the rapid mortification of the ancient group of dentists.

History of Dentistry

[Psychophysical prerequisites and mental performance of school children].

By extensive investigations and statistical calculations it is possible to establish the psychophysical prerequisites for performance, which consist of "mental processing speed" and "vegetative reactivity". These can be developed by training and thus contribute to improved mental performance.

Achievement

Central nervous system effects of antihistamines on evoked potentials.

Sedation is the most common side effect of antihistamine therapy. As with many behavioral constructs, attempts at quantification are difficult, and consequently, subjective reports of antihistamine sedation are frequently relied upon. Evoked potential activity is one method to quantitate the brain's response to subtle cognitive change. Evoked potentials are characteristic shifts in the brain's electrical activity that are obtained by time-locking the ongoing EEG to a stimulus over repeated trials. A late positive component of the evoked potential (P3) has been related to various psychologic properties including expectation, selective attention, and information processing speed. Because of this relationship, we employed the latency of the P3 evoked potential to measure the cognitive effects of chlorpheniramine and terfenadine. In healthy young subjects, we observed that terfenadine produces significantly less cognitive slowing of the P3 potential than chlorpheniramine. This finding supports the subjective findings of reduced sedative side effects of terfenadine.

Adult

[Design and application of laser-disk for clinical pulmonary data base system using the personal computer].

A database system is described for managing the information on pulmonary function test (PFT) measured by three different PFT devices. The data is transmitted into a personal computer, FM-11AD2+ (FUJITSU CO., LTD.) with a 20 MB hard disk and a 800 MB laser disk. Multitasking OS, OS-9/6809, is used to operate the software. PFT data of about 15,000 cases may be stored, which can be easily retrieved for research and discussions on a case study. Despite the present limitation of the processing speed and the capacity of the hard disk, this system is useful because it allows to provide reports readily.

Database Management Systems

Effect of maternal antibody on timing of initial vaccination of young white leghorn chickens against infectious bursal disease virus.

Maternal antibody titers in white leghorn chicks against infectious bursal disease virus (IBDV) were measured by a computer-assisted, single-serum-dilution, indirect kinetic-based enzyme-linked immunosorbent assay (KELISA) and by a virus-neutralization (VN) test in order to predict the timing of initial vaccination. Day-old white leghorns were from unvaccinated pullets or from pullets vaccinated either four times or twice with IBDV commercial vaccines. The chicks were immunized once via the drinking water with a commercial "intermediate" live IBDV vaccine at 1, 15, or 28 days of age. Effective initial immunization was confirmed by an increase in antibody to IBDV (serologic conversion) that occurred when maternal antibody decreased to 8 and 9 on a log2 scale. This concentration of antibody was detected between 24 and 28 days of age. The computer-assisted IBDV-KELISA increased the sample processing speed for detecting IBDV antibody, and it was as sensitive as the VN test for predicting the timing of initial IBDV vaccination.

Animals

The physician data query (PDQ) cancer information system.

PDQ is an online database that provides information about the prognosis and treatment of all major types of cancer. It represents a major effort by the NCI to communicate advances in cancer treatment using computer technology, and serves as a major component of the Institute's program to reduce cancer mortality nationwide. PDQ utilizes a modern large-scale computer to provide processing speed, a general purpose database management system to provide retrieval and display functions, and commercial telecommunication networks to provide online access to up-to-date information on cancer treatment. A series of user-friendly menus allow searching, browsing, and displaying without having to learn a specialized search language. PDQ is accessible through the National Library of Medicine's computer system via a computer terminal or personal computer and is available to the medical community at over 6,000 medical libraries and centers and through individual access codes. PDQ is also available as an online database under a special license agreement with NCI through two medical information systems produced by commercial database vendors: BRS/Saunders' COLLEAGUE Mead Data Central's MEDIS, and Telmed, a Swiss database.

Clinical Trials as Topic

The Edinburgh-Helsinki study: a comparison of dental care for children.

A comparison was undertaken of dental care for children in Edinburgh and Helsinki. The evaluation centred upon an epidemiological investigation of the dental health of children in the 5-, 12- and 15-year age groups. This was performed by examiners using standardized procedures who were drawn from both countries. They employed an established system of data recording and processing (SPEED). Using these data, and background information from official and other sources, an assessment was made of the effectiveness, adequacy, efficiency and appropriateness of the services. Children's dental health, particularly in the youngest age group, was generally better in Helsinki than in Edinburgh as were both the population coverage and extent to which disease was controlled. However, the services in Edinburgh were marginally the more economically efficient. This arose from their being provided mainly by independent contractors working under a fee per item of service rather than by a public salaried system. In neither city was the delivery of dental services supplemented by water fluoridation nor was extensive use made of auxiliary personnel. The decrease in caries prevalence in recent years has profound implications for the dental services in both countries. It calls for continuing re-appraisal of present policies on expenditure, manpower, dental education and ways of delivering dental care.

Adolescent