Brain injury as a result of violence: preliminary findings from the traumatic brain injury model systems

OBJECTIVES

To identify possible risk factors that may predispose individuals to violent traumatic brain injury (TBI) and to determine the effect of etiology of injury on outcomes.

STUDY DESIGN

Prospective, longitudinal multicenter study.

SETTING

TBI Model Systems (TBIMS) located at Wayne State University/Rehabilitation Institute of Michigan, Detroit, MI; The Institute for Rehabilitation and Research, Houston, TX; Medical College of Virginia, Richmond, VA; and Santa Clara Valley Medical Center, San Jose, CA.

SUBJECTS

Individuals treated in the four TBIMS programs between 3/89 and 9/96 who met the criteria for inclusion in the TBIMS National Database and for whom the etiology was known (n=812).

MAIN OUTCOME MEASURES

Functional Independence Measure, Alcohol Quantity Frequency Variability Index, Community Integration Questionnaire.

RESULTS

Individuals who incur violence-related TBI tend to be male, nonwhite, unmarried, living alone, less educated, and unemployed at time of injury. They tend to have less severe brain injuries and better motor function at the time of admission to inpatient rehabilitation. At 1 year postinjury, they score lower on community integration measures; however, no difference exists in functional status. Etiology of injury was found to only play a minor role in the prediction of social and productive integration at 1 year postinjury.

CONCLUSIONS

Survivors of violent and nonviolent TBI have similar functional outcomes; however, they differ in preinjury and postinjury socio-economic characteristics, injury severity, and postinjury community integration. Socio-economic factors appear to play a large role in the risk for violent injury and in community integration following injury.

Transition metals as protease inhibitors

An alternative approach to the development of clinically useful protease inhibitors was investigated. The approach utilized coordination chemistry of transition metal ions rather than substrate analogs to block active sites of these enzymes. In the case of serine proteases it was found that aqueous Ti(IV) is a potent inhibitor of the trypsin subclass, but not the chymotrypsin subclass. The direct binding of Ti(IV) to trypsin was made possible by the presence of a free carboxyl group at the bottom of the substrate binding pocket of the enzyme, and the five-coordinate geometry of TiO(SO4)(H2O). Although initial binding of Ti(IV) was reversible, it was followed in time by irreversible inhibition. Direct binding of octahedral or tetrahedral metal ion complexes was prevented by the inability of the enzyme active sites to promote formation of a five-coordinate transition state of the metal ion required for reaction. These studies demonstrate the ability of direct metal ion binding as a way to enhance blocking of enzyme active sites as compared with that of traditional organic inhibitors. Application of these findings was investigated by measuring the affect Ti(IV) had on growth of Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa. Five-coordinate titanyl sulfate completely inhibited the growth of these organisms. This suggests that five-coordinate titanyl sulfate, which is easier and less expensive to manufacture than conventional antibiotics, may be useful in controlling endemic infections of E. coli and S. typhimurium.

Pulmonary agenesis: a predictor of ipsilateral malformations

Pulmonary agenesis is a rare malformation that can be isolated or associated with other anomalies. We became interested in pulmonary agenesis after evaluation of a child with right pulmonary agenesis, an unlobed left lung, bilateral cleft lip and palate, maxillary and mandibular hypoplasia, bilateral microtia, bilateral radial ray hypoplasia, horseshoe kidney, and complex congenital heart disease. A review of the occurrence of pulmonary agenesis with other congenital anomalies uncovered a striking association with ipsilateral radial ray defects and/or hemifacial microsomia. The presence of bilateral facial or radial ray anomalies was indicative of bilateral pulmonary involvement. A review of the cases of pulmonary agenesis and associated anomalies at the Children's Hospital and Medical Center confirmed the association of pulmonary agenesis and ipsilateral involvement of face and/or radial ray. The association of pulmonary agenesis and ipsilateral malformations may shed light on its pathogenesis. Although the cause of these associated anomalies remains unclear, abnormalities in the development of the aortic arches during embryogenesis is an attractive hypothesis.

Pulmonary agenesis: a predictor of ipsilateral malformations

Pulmonary agenesis is a rare malformation that can be isolated or associated with other anomalies. We became interested in pulmonary agenesis after evaluation of a child with right pulmonary agenesis, an unlobed left lung, bilateral cleft lip and palate, maxillary and mandibular hypoplasia, bilateral microtia, bilateral radial ray hypoplasia, horseshoe kidney, and complex congenital heart disease. A review of the occurrence of pulmonary agenesis with other congenital anomalies uncovered a striking association with ipsilateral radial ray defects and/or hemifacial microsomia. The presence of bilateral facial or radial ray anomalies was indicative of bilateral pulmonary involvement. A review of the cases of pulmonary agenesis and associated anomalies at the Children's Hospital and Medical Center confirmed the association of pulmonary agenesis and ipsilateral involvement of face and/or radial ray. The association of pulmonary agenesis and ipsilateral malformations may shed light on its pathogenesis. Although the cause of these associated anomalies remains unclear, abnormalities in the development of the aortic arches during embryogenesis is an attractive hypothesis.

The effect of short-term diets rich in fish, red meat, or white meat on thromboxane and prostacyclin synthesis in humans

Foods which increase tissue arachidonic acid levels have been proposed to increase thrombosis tendency, presumably through increased platelet aggregation. This study examined the effect of doubling the dietary arachidonic acid (20:4n-6) using meat- or fish-based diets on the systemic production of prostacyclin (PGI2) and thromboxane (TXA2) in 29 healthy, nonsmoking adults. There were three, 3-wk low-fat dietary periods (< 15% energy as fat) in which subjects consumed a vegetarian diet for 1 wk followed by 2 wk on diets containing meat or fish as sources of 20:4n-6. Between each diet period, there was a 3-wk washout period, during which subjects returned to their normal diets. The level of 20:4n-6 consumed during the last 2 wk of each study was approximately double the usual intake (mean 140 mg/d), while the mean eicosapentaenoic acid (20:5n-3) content of the diets varied from 1 mg/d on the white meat diet to 70 mg/d on the red meat diet and to 847 mg/d on the fish diet. The serum phospholipid (PL) 20:4n-6/20:5n-3 ratios were 11:1 on the vegetarian diet, 15:1 on the white meat diet, 8:1 on the red meat diet, and 2:1 on the fish diet (P < 0.001). Neither white nor red meat diets affected platelet 20:4n-6 levels, platelet aggregation, ex vivo platelet TXB2 production, or the systemic PGI2 or TXA2 production as measured by gas chromatography-mass spectrometry analysis of the excretion levels of the principal urinary metabolites 2,3-dinor-6-keto-PGF1 alpha (PGI2-M) and 11-dehydro-TXB2 (TXA2-M), respectively. The fish diet decreased the 20:4n-6/20:5n-3 ratio in platelet PL from the baseline level of 45:1 to 13:1 (P < 0.001), had no effects on platelet aggregation, but significantly decreased platelet TXB2 production (collagen-stimulated) and TXA2-M production, while PGI2-M levels were unaltered. These results indicate that short-term diets which double the usual 20:4n-6 intake using white meat (175-330 g/d) or red meat (275-530 g/d) are not associated with an increased TXA2 production, but this does not rule out the adverse effects of 20:4n-6 at higher levels in the diet, or for more prolonged periods. Short-term diets containing fish (100-200 g/d with 90-210 mg/d 20:4n-6 and approximately 650-1000 mg/d 20:5n-3) led to significant increases in platelet 20:5n-3 levels and a decrease in the ex vivo and systemic TXA2 production.

Telecommunications role evolves beyond mere utility

A more regionalized healthcare delivery system has expanded the role of the telecommunications department. Applications such as teleradiology and telemedicine are making increasingly sophisticated demands on communications systems and their managers.

Engineered immunoglobulin molecules as vehicles for T cell epitopes

The variable regions (V) of immunoglobulins (Ig) bear antigenic determinants that can stimulate both humoral and cellular immune responses subsequent to hetero, allo or iso-immunization. The expression of these determinants by Igs usually correlates with the presence of specific amino acid residues within the CDR loops of the V regions. Since the CDR loops varies in length, we reasoned that they would represent permissive sites to insert foreign peptides and create antigenized Igs expressing selected determinants. Taking advantage of these properties and the fact that Igs are self and long-lived molecules, we expressed a CTL and a helper epitope of influenza virus nucleoprotein and hemagglutinin respectively, within the heavy chain CDR3 loop of an anti-arsonate antibody. We found that foreign peptides comprised of 11 to 15 amino acid residues can be expressed within the V region of the heavy chain without alteration of pairing with the light chain. More striking, the cellular processing machinery is able to generate the peptides from the Ig context which were then recognized by specific T cells. Furthermore, the engineered Igs are able to induce T cell responses specific for the inserted peptide and for influenza virus. The use of engineered Ig molecules as vehicles for T and B cell peptides might represent a valuable strategy to generate safe, long lived reagents able to stimulate strong specific immune responses. This would then overcome the short half life of synthetic peptides based vaccines and the side effects seen in case of recombinant viral proteins or inactivated viruses based vaccines.

Description and interobserver reliability of the Tufts Assessment of Motor Performance

This paper describes the conceptual basis for the development of a new clinical evaluation instrument, the Tufts Assessment of Motor Performance (TAMP). The TAMP is a 32-item, diagnosis-independent, criterion-referenced test that samples physical performance items in the areas of mobility, activities of daily living and physical aspects of communication. The administrative and scoring criteria of the TAMP are presented, and the multiple measurement dimensions are described. The documentation of patient status and progress, as described in the functional and performance profiles, is outlined. The paper also reports initial interobserver reliability on the intraitem tasks and the summary indexes of the two profiles. Forty individuals (20 adults and 20 children) with neurologic and musculoskeletal disorders comprised the reliability sample. Kappa and intraclass correlations were used to estimate the reliability of three independent raters on individual tasks and aggregate scores, respectively. Task reliability for the assistance and approach measurement dimensions were generally higher than for the more qualitative pattern and proficiency dimensions. Yet over 90% of all the tasks had acceptable reliability, while all the summary indexes had high interobserver reliability. Determination of interobserver reliability data is the initial phase of defining the most appropriate and technically valuable items, and will serve as a basis for item revision and reduction to enhance the clinical utility of the test.

Survey of computer-assisted electrocardiography in the United States

The purpose of this study was to update a 1976 study by Arthur D. Little, Inc., on the use of automatic ECG analysis systems. Thirteen vendors of computerized ECG systems received survey forms in 1987 and a follow-up telephone survey was completed in early 1988. The vendors surveyed included service bureaus and providers of computer-based data management and analysis systems and analysis carts. Analysis carts were subdivided into standard-sized and portable analysis carts. The technical specifications used by the respondents varied from 3 simultaneous leads to 14 simultaneous leads. The standards used were AHA, AAMI, and ANSI. Various compression techniques were used. The method of testing adult, pediatric, and serial comparison programs varied from the use of expert electrocardiographers to non-ECG data bases. Service bureau customers consisted mainly of general practitioners and primary care physicians' offices, with an estimated 1.2 million ECGs processed in 1987. Analysis and data management systems mainly serviced large hospitals, with an estimated 15 million ECGs processed in 1987. Standard-sized analysis carts used in hospitals and physicians' offices were estimated to process over 31 million ECGs in 1987. Portable analysis carts installed in hospitals, primary care, and general practitioners' offices and clinics processed almost 7 million ECGs in 1987. Computerized ECG analysis has been one of the most rapidly and widely adopted computer applications in medicine; its potential benefits in improving quality and consistency of interpretations has long been recognized. This study indicates that additional information on accuracy of current ECG software is needed to ensure that the technology is optimally applied in patient care.

The distribution of lung damage in children with cystic fibrosis and its relationship to colonisation with Pseudomonas aeruginosa

Ventilation-perfusion lung scans were performed with 81mKr inhalation and 99mTc-albumin injection in 33 children with cystic fibrosis. It was found that both ventilation and perfusion scans yielded more information than radiographs of the chest in assessing lung damage. Using a scoring system, it was demonstrated by statistical methods that in the worst affected patients the disease was worse in the upper zones of the lungs, which changes were not detectable on chest radiographs. Pseudomonas was present in the sputum of these patients.

The child health clinic: results of a new strategy of community care in a deprived area

Substantial changes were made in the organisation of a child health clinic serving an underprivileged population in Nottingham. A community paediatric team approach was adopted, routine medical checks were reduced, and referrals from elsewhere (including parents) were encouraged. The changes resulted in an older and more deprived population of preschool children being seen by the clinic doctors. More treatable medical disorders were detected with this approach.

Prevalence of morning hyperglycaemia: determinants of fasting blood glucose concentrations in insulin-treated diabetics

A rise in blood glucose concentration at the end of the night, and consequent morning hyperglycaemia, are well recognized events in some diabetic patients. In 94 patients on twice daily insulin injections we have examined the prevalence and extent of morning hyperglycaemia, and its relation to control, insulin therapy, and insulin antibody levels. Blood glucose reached the highest level of the day before or after breakfast in 83% of patients, and in 50% this value was 2 mmol/l greater than any other time of day. Patients with higher fasting concentrations did not have worse blood glucose control over the rest of the day. No correlation was found between fasting blood glucose concentrations and the evening dose of intermediate acting insulin or the level of insulin antibodies. No consistent change in fasting blood glucose concentrations occurred with changes in antibody levels in patients switched between pork and beef insulin. Morning hyperglycaemia was as common with both insulin species. Pre- and post-breakfast hyperglycaemia is common and significant in insulin-treated diabetic patients. It is not directly related to diabetic control at other times of the day, and is independent of insulin species and insulin antibody levels.

Ultrastructure of Nocardia-like variants of Mycobacterium smegmatis and chemical composition of the basal cell wall layer

Mycobacterium smegmatis, its orange-red--pigmented (OR) variants, and back mutant strains were examined by electron microscopy using ultrathin sectioning, negative or positive staining, and freeze-fracture-etching methods. The parental and back mutant strains showed almost identical ultrastructures. Specifically, thick ramified fibers measuring about 15 nm in diameter were always visible in the positively stained cell wall, although they were not readily visualized with negative staining or freeze-fracture-etching. In contrast, the cell walls of OR variants contained fibrous networks measuring about 11 nm in diameter, which could be observed by positive and negative staining as well as freeze-fracture-etching. Although cytoplasmic structures appeared similar among the four strains examined, mesosomes were significantly more abundant in the OR variants. The basal layer of the cell wall obtained as a phenol residue consisted of a dense membranous matrix containing scattered fibrous structures in the parental and back mutant strains, and fibrous networks in the OR variants. Chemical analyses showed that the basal layers of all four strains contained the same neutral sugars, amino sugars, and amino acids, i.e., arabinose, galactose, muramic acid, glucosamine, alanine, glutamic acid, and diaminopimelic acid. The alpha-branched, beta-hydroxylated fatty acids contained in the basal layers differ among the four strains, however, with nocardomycolic acids being present in the OR variants and mycolic acids in the parental and back mutant strains. Our previous conclusion that OR variants of M. smegmatis have characteristics similar to those of nocardia is supported by the present study.

Coupling between the initiation of DNA replication and cell division in the blue-green alga Anacystis nidulans

The effect of mitomycin C on cell mass increase, cell division, RNA synthesis and DNA synthesis in the blue-green alga Anacystis nidulans has been examined. Data suggests that the initiation of DNA replication, rather than its termination was the necessary event for cell division to occur.

Isolation and characterization of nocardia-like variants of Mycobacterium smegmatis

Orange-red-pigmented (OR) colonies were isolated from cream-yellow-pigmented Mycobacterium smegmatis after exposure to either mycobacteriophage MC4 or ultraviolet light; these variant strains were designated OR4 and ORuv, respectively. Early subculture of OR-colonies did not show any segregation of parental-type cells. However, colonies resembling the parental strains, possibly representing a back mutant (REV-OR4), were occasionally found during subculture of established OR-colonies or upon treatment with N-nitrose-N'-nitro-N-methylguanidine. The OR-variants were characterized by their lytic response to nocardiophage, but not to mycobacteriophages, presence of alpha-branched, beta-hydroxylated fatty acids of the Nocardia-type, and a guanine plus cytosine value of deoxyribonucleic acid (DNA) between 62 and 64 mol%. They were more resistant to the lethal action of both ultraviolet light and mitomycin C treatment than the parental and back mutant strains. Although the OR-variants in this study possess characteristics common to the genus Nocardia or some of the 'rhodochrous' mycobacteria, evidence is presented that they form a new class of mycobacterial variants.