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Long term results after multiple injuries including severe head injury.

OBJECTIVE: To describe the long term results in patients with multiple injuries including severe head injury. DESIGN: Retrospective and prospective clinical study. SETTING: Level I trauma centre, Germany. PATIENTS: Patients aged 16-60 years who had been injured more than 2 years before, whose Injury Severity Score was over 20 and whose cranial Abbreviated Injury Score (AIS) was over 3. MAIN OUTCOME MEASURES: Glasgow Outcome Scale (GOS), functional, neuropsychological, vocational and social outcomes. RESULTS: 58 patients, median age 24 (range 16-53, interquartile range (IQR) 21-32) years were investigated 5 (3-9; IQR 4-7) years after their injury. Median ISS was 34 (21-57; IQR 26-41) and GCS 6 (3-8; IQR 4-7). Duration of coma was 10 (2-51; IQR 7-22) days and neurological rehabilitation lasted 169 (10-830; IQR 80-300) days. Movements of the elbow and ankle was most impaired by injury. All psychometric tests showed deficits, particularly in speed of processing, concentration, recent memory, and learning performance. The social environment had been changed in half and vocational rehabilitation was dependent on age. 24 (42%) returned to their former profession, 18 (31%) were retrained to another profession, 16 (27%) were unemployed or retired on a pension. 31 (53%) made a good recovery with moderate disability, 19 (33%) had severe disability, and 8 (14%) remained in a persistent vegetative state assessed by the GOS. CONCLUSION: Early and concentrated rehabilitation facilitates functional, social, and neuropsychological reintegration.

Adolescent↗

Neuropsychological studies of mild traumatic brain injury: a meta-analytic review of research since 1995.

A meta-analysis conducted by Binder, Rohling and Larrabee established a relationship between mild traumatic brain injury (TBI) and small reductions in cognitive functioning in individuals assessed more than 3 months post-injury. As a follow-up, this study summarized similar research that (1) was published since the previous meta-analysis, and (2) included data collected at any stage post-injury. An extensive literature search revealed 17 suitable studies from which effect sizes were aggregated. The overall effect size was g = 0.32, p < .001. Speed of processing measures had the largest effect, g = 0.47, p < .001. The merging of post-acute effect sizes with those reported in Binder et al.'s review yielded a nonsignificant result, g = 0.11. Time since injury was found to be a significant moderator variable, with effect sizes tending to zero with increasing time post injury.

Brain Injuries↗

Cognitive functioning and everyday problem solving in older adults.

The relationship between cognitive functioning and a performance-based measure of everyday problem-solving, the Everyday Problems Test (EPT), thought to index instrumental activities of daily living (IADL), was examined in 291 community-dwelling non-demented older adults. Performance on the EPT was found to vary according to age, cognitive status, and education. Hierarchical regression analyses revealed that, after adjusting for demographic and health variables, measures of cognitive functioning accounted for 23.6% of the variance in EPT performance. In particular, measures of global cognitive status, cognitive decline, speed of processing, executive functioning, episodic memory, and verbal ability were significant predictors of EPT performance. These findings suggest that cognitive functioning along with demographic variables are important determinants of everyday problem-solving.

Activities of Daily Living↗

A meta-analysis of the neuropsychological effects of adjuvant chemotherapy treatment in women treated for breast cancer.

Given the improvement in mortality rates associated with breast cancer, the importance of understanding the long-term neuropsychological consequences of chemotherapy is becoming increasingly vital. This study applies meta-analytic techniques to the scant literature on the relationship between contemporary adjuvant chemotherapy treatment for breast cancer and cognitive dysfunction as examined through neuropsychological indices. Seven studies (involving more than 300 participants) were selected from over 200 potential articles, based on three inclusion criteria: presence of breast cancer, administration of chemotherapy treatment, and use of neuropsychological tests. From these, nine treatment-control comparisons were used to generate 129 Hedge's d effect sizes across the cognitive domains of simple attention, working memory short- and long-term memory, speed of processing, language, spatial abilities, and motor function. Small to medium cumulative effect sizes, showing diminished cognitive function for chemotherapy treatment groups compared to control groups, were obtained for each of the eight cognitive domains. Overall, these results suggest that women who undergo adjuvant chemotherapy as treatment for breast cancer may experience subtle yet consequential cognitive decline.

Breast Neoplasms↗

A Dictyostelium mutant deficient in severin, an F-actin fragmenting protein, shows normal motility and chemotaxis.

A severin deficient mutant of Dictyostelium discoideum has been isolated by the use of colony immunoblotting after chemical mutagenesis. In homogenates of wild-type cells, severin is easily detected as a very active F-actin fragmenting protein. Tests for severin in the mutant, HG1132, included viscometry for the assay of F-actin fragmentation in fractions from DEAE-cellulose columns, labeling of blots with monoclonal and polyclonal antibodies, and immunofluorescent-labeling of cryosections. Severin could not be detected in the mutant using these methods. The mutation in HG1132 is recessive and has been mapped to linkage group VII. The mutant failed to produce the normal severin mRNA, but small amounts of a transcript that was approximately 100 bases larger than the wild-type mRNA were detected in the mutant throughout all stages of development. On the DNA level a new Mbo II restriction site was found in the mutant within the coding region of the severin gene. The severin deficient mutant cells grew at an approximately normal rate, aggregated and formed fruiting bodies with viable spores. By the use of an image processing system, speed of cell movement, turning rates, and precision of chemotactic orientation in a stable gradient of cyclic AMP were quantitated, and no significant differences between wild-type and mutant cells were found. Thus, under the culture conditions used, severin proved to be neither essential for growth of D. discoideum nor for any cell function that is important for aggregation or later development.

Actins↗

Breathing down the neck of Unc104.

The Unc104/Kif1A class of kinesins transports synaptic vesicle precursors along microtubules with high speed and processivity that has been proposed to depend on reversible dimerization between two poorly motile monomers. In this issue, Al-Bassam et al. (2003) discover a structural basis for regulation of motility by reversible dimerization.

Animals↗

A novel algorithm for non-bonded-list updating in molecular simulations.

Simulations of molecular systems typically handle interactions within non-bonded pairs. Generating and updating a list of these pairs can be the most time-consuming part of energy calculations for large systems. Thus, efficient non-bonded list processing can speed up the energy calculations significantly. While the asymptotic complexity of current algorithms (namely O(N), where N is the number of particles) is probably the lowest possible, a wide space for optimization is still left. This article offers a heuristic extension to the previously suggested grid based algorithms. We show that, when the average particle movements are slow, simulation time can be reduced considerably. The proposed algorithm has been implemented in the DistanceMatrix class of the molecular modeling package MESHI. MESHI is freely available at .

Algorithms↗

In vivo characterization of traumatic brain injury neuropathology with structural and functional neuroimaging.

Quantitative neuroimaging is increasingly used to study the effects of traumatic brain injury (TBI) on brain structure and function. This paper reviews quantitative structural and functional neuroimaging studies of patients with TBI, with an emphasis on the effects of diffuse axonal injury (DAI), the primary neuropathology in TBI. Quantitative structural neuroimaging has evolved from simple planometric measurements through targeted region-of-interest analyses to whole-brain analysis of quantified tissue compartments. Recent studies converge to indicate widespread volume loss of both gray and white matter in patients with moderate-to-severe TBI. These changes can be documented even when patients with focal lesions are excluded. Broadly speaking, performance on standard neuropsychological tests of speeded information processing are related to these changes, but demonstration of specific brain-behavior relationships requires more refined experimental behavioral measures. The functional consequences of these structural changes can be imaged with activation functional neuroimaging. Although this line of research is at an early stage, results indicate that TBI causes a more widely dispersed activation in frontal and posterior cortices. Further progress in analysis of the consequences of TBI on neural structure and function will require control of variability in neuropathology and behavior.

Brain Injuries↗

The effects of age, glucose ingestion and gluco-regulatory control on episodic memory.

BACKGROUND: Previous research has been inconclusive regarding the impact of glucose ingestion and gluco-regulatory control on cognitive performance in healthy older adults. The aim of this research was to determine whether glucose specifically enhanced episodic memory in an older population. In addition, the link between individual differences in glucose regulation and the magnitude of the enhancement effect was examined. DESIGN AND SUBJECTS: A within subjects, counterbalanced, crossover design was used with 20 participants (60-80 year olds), each serving as his/her control. METHODS: Episodic memory was tested by presenting unrelated paired associates followed by immediate and delayed cued recall, and delayed recognition, under single and dual task conditions. In addition, a battery of cognitive tests was administered, including tests of semantic memory, working memory and speed of processing. RESULTS: Glucose ingestion was found to largely facilitate performance of episodic memory. Furthermore, subsidiary analyses found that gluco-regulatory efficiency predicted episodic memory performance in both control and glucose conditions. CONCLUSIONS: A boost in performance after glucose ingestion was particularly seen in the episodic memory domain. Notably, strong evidence was provided for the utility of gluco-regulatory control measures as indicators of cognitive decline in the elderly.

Aged↗

Processing control and cost in bacteriology.

Controlled processing was applied to lower respiratory, wound, and cervicovaginal exudates, and urine. The extent of processing was determined by assessment of quality in direct smears and/or by limits placed on complete identification and antimicrobial susceptibility testing of isolates in mixed cultures. Some specimens were not cultured; others were cultured, but certain isolates were identified by colonial morphologic features only. The time in minutes for performing 22 processing operations was determined. The average number of operations performed with processing control was established along with the total cost per minute of labor expended. A 19% reduction was observed in the time expended with controlled processing relative to projected time expended without processing controls. Urine specimens yielded the greatest saving. Processing control speeds recollection of poor-quality specimens, provides reporting of results of examination of all Gram-stained direct smears, minimizes reporting of information potentially misleading to physicians, and may reduce other health-care costs through improved patient care.

Bacteria↗

The evolution of restricted recombination and the accumulation of repeated DNA sequences.

We suggest hypotheses to account for two major features of chromosomal organization in higher eukaryotes. The first of these is the general restriction of crossing over in the neighborhood of centromeres and telomeres. We propose that this is a consequence of selection for reduced rates of unequal exchange between repeated DNA sequences for which the copy number is subject to stabilizing selection: microtubule binding sites, in the case of centromeres, and the short repeated sequences needed for terminal replication of a linear DNA molecule, in the case of telomeres. An association between proximal crossing over and nondisjunction would also favor the restriction of crossing over near the centromere. The second feature is the association between highly repeated DNA sequences of no obvious functional significance and regions of restricted crossing over. We show that highly repeated sequences are likely to persist longest (over evolutionary time) when crossing over is infrequent. This is because unequal exchange among repeated sequences generates single copy sequences, and a population that becomes fixed for a single copy sequence by drift remains in this state indefinitely (in the absence of gene amplification processes). Increased rates of exchange thus speed up the process of stochastic loss of repeated sequences.

Animals↗

Age differences in the speed of a spatial cognitive process.

Older subjects responded slower than younger subjects on a spatial task which required them to rotate mentally a perspectively drawn figure in order to judge whether it was congruent with a second figure. Decision time was partitioned into two components: (1) the time taken for the "mental rotation" process, (2) the time taken for the remaining processes such as stimulus encoding and motor output. Both components required more time in the elderly group. The increase with age in the component of decision time representing rotational processes was similar to those increases seen by other investigators examining age-dependent differences in time required for memory-scanning processes using verbal stimuli.

Adolescent↗

Report of the International Workshop on Screening for Breast Cancer.

BACKGROUND: Over the past 30 years, eight major randomized controlled trials of breast cancer screening--with mammography and/or clinical breast examination--have been conducted. Results from several trials have been updated during the past year, and initial results of three other trials have been reported. PURPOSE: The National Cancer Institute held an International Workshop on Screening for Breast Cancer in February 1993 to conduct a thorough and objective critical review of the world's most recent clinical trial data on breast cancer screening, consider the new evidence, assess the current state of knowledge, and identify issues needing further research. METHODS: Investigators representing the eight randomized controlled trials of breast cancer screening in women aged 40-74 presented published and unpublished data. Evidence relating to the effectiveness of breast cancer screening in different age groups, especially women aged 40-49, was presented. RESULTS: For women aged 40-49, randomized controlled trials consistently demonstrated no benefit from screening in the first 5-7 years after study entry. A meta-analysis of six trials found a relative risk of 1.08 (95% confidence interval = 0.85-1.39) after 7 years' follow-up. After 10-12 years of follow-up, none of four trials have found a statistically significant benefit in mortality; a combined analysis of Swedish studies showed a statistically insignificant 13% decrease in mortality at 12 years. Only one trial (Health Insurance Plan) has data beyond 12 years of follow-up, and results show a 25% decrease in mortality at 10-18 years. Statistical significance of this result is disputed, however. In women aged 50-69, all studies show mortality reductions; three of four studies show reductions of about 30% at 10-12 years after study entry. Results from two of these trials were statistically significant. Too few women over age 70 have been included in studies for adequate analysis. CONCLUSIONS: For women aged 40-49, randomized controlled trials of breast cancer screening show no benefit 5-7 years after entry. At 10-12 years, benefit is uncertain and, if present, marginal; thereafter, it is unknown. For women aged 50-69, screening reduces breast cancer mortality by about a third. Currently available data for women age 70 or older are inadequate to judge the effectiveness of screening. IMPLICATIONS: Randomized trials have provided stronger scientific evidence regarding the effectiveness of screening for breast cancer than for any other cancer. However, much still needs to be learned. Periodic gatherings of scientists in the field should speed the process.

Adult↗

New techniques for physical mapping of the human genome.

We describe improvements in techniques and strategies used for making maps of the human genome. The methods currently used are changing and evolving rapidly. Today's techniques can produce ordered arrays of DNA fragments and overlapping sets of DNA clones covering extensive genomic regions, but they are relatively slow and tedious. Methods under development will speed the process considerably. New developments include a range of applications of the polymerase chain reaction, enhanced procedures for high resolution in situ hybridization, and improved methods for generating, manipulating, and cloning large DNA fragments. More detailed genetic and physical maps will be useful for finding genes, including those associated with human diseases, long before the complete DNA sequence of the human genome is available.

Base Sequence↗

Porcine xenografts in the treatment of pressure ulcers.

Porcine heterografts are effective in the treatment of cutaneous ulcers as biological bandages that promote healing by: speeding the processes of granulation and epithelialization; maintaining a clean covering over the wound; reducing loss of fluid and protein; and preventing bacterial encroachment.

Animals↗

Neuropsychological impairments, vocational outcomes, and financial costs for individuals with traumatic brain injury receiving state vocational rehabilitation services.

OBJECTIVE: To determine the relationship among neuropsychological variables, vocational outcomes, and vocational costs for Missouri Division of Vocational Rehabilitation (MO-DVR) clients with traumatic brain injury (TBI). DESIGN: Clients referred for neuropsychological evaluations were followed until DVR case closure. Subjects were grouped according to the following DVR status at case closure: Successfully Employed, Services Interrupted, and No Services Provided. Spearman correlations with Bonferroni corrections were calculated to determine relationships among variables, and Kruskal-Wallis nonparametric one-way analyses of variance (ANOVAs) were conducted to evaluate differences in DVR group status in terms of neuropsychological variables and DVR costs. SETTING: All evaluations were completed through a Midwestern university neuropsychology laboratory. PATIENTS: 110 consecutively referred DVR clients with nonacute TBI referred for neuropsychological evaluation. MAIN OUTCOME MEASURES: Absolute level (ie, raw/standard scores) of neuropsychological functioning and relative degree of decline in: intelligence (WAIS-R), memory (WMS-R General and Delayed Memory Indices), attention (WMS-R Attention Index), speed of processing (Trails A), and cognitive flexibility (Trails B); DVR costs at closure. RESULTS: 1) Surprisingly, the Successfully Employed group had significantly greater neuropsychological impairments; 2) Greater decline in delayed memory was associated with higher DVR costs (r = -0.30, P <.05); and 3) More indices of relative decline were significantly correlated with vocational outcomes (5/6) than were indices of absolute functioning (3/6). CONCLUSIONS: DVR is effective in providing services to individuals with the most significant neuropsychological deficits; it is important to consider both absolute level of functioning and relative decline in functioning when evaluating TBI.

Adolescent↗

Rule #1: Don't reinvent the wheel.

These are the things we recommend to speed the process along: Ask for input from key decision makers at the outset. Ask for input from the people who will be using the form, particularly patients. Highlight on the revised form the content that is different from the previous version. This way it is quicker for the decision-makers to read and they don't have to rehash what is already successfully in use. "Hand-walk" the form from person to person to obtain approval signatures. There are few things that are worse to lose in interoffice mail!

Ambulatory Surgical Procedures↗