Outcome of severe brain injury: a multimodality neurophysiologic study

We screened all head-injured trauma patients admitted to Lehigh Valley Hospital during a 2-year period. From 725 screened patients, 69 patients in a coma on the second day after trauma were entered into this study. During the first week, these patients underwent electroencephalography (EEG), evoked potentials, ocular pneumoplethysmography, and transcranial Doppler (TCD) sonography. Clinical examinations were undertaken 2 and 7 days after trauma. Test results were correlated with functional clinical outcome at 6 months. In a multiple regression analysis, EEG was the major independent variable that significantly predicted 6-month outcome based on Glasgow Outcome Scale score. Transcranial Doppler sonography contributed a small additional component. Though EEG was the most significant predictive factor in this neurophysiological battery, it did not add significantly to the predictive power of Glasgow Coma Scale score determined at day 7. These findings suggest that in neurophysiologic testing in this type of patient is not useful in improving predictive outcome data.     

US national survey of physician practices for the secondary and tertiary prevention of ischemic stroke. Design, service availability, and common practices

BACKGROUND AND PURPOSE: Stroke is largely a preventable disease. However, there are little data available concerning the use of stroke prevention diagnostic and treatment modalities by practicing physicians. These data are critical for the rational allocation of resources and targeting of educational efforts. The purposes of this national survey were to gather information about physicians' stroke prevention practice patterns and their attitudes and beliefs regarding secondary and tertiary stroke prevention strategies. METHODS: We conducted a national survey of stroke prevention practices among a stratified random sample of 2000 physicians drawn from the American Medical Association's Physician Masterfile. The survey focused on the availability of services and the use of diagnostic and preventive strategies for patients at elevated risk of stroke. RESULTS: Sixty-seven percent (n = 1006) of eligible physicians completed the survey. Diagnostic studies considered readily available by at least 90% of physicians included carotid ultrasonography, transthoracic echocardiography, Holter monitoring, and brain CT and MRI scans. MR angiography was perceived as being readily available by 68% and transesophageal echocardiography by 74% of respondents. Twelve percent of physicians reported cerebral arteriography and 10% reported carotid endarterectomy as not being readily available. Multiple logistic regression analyses showed that the availability of services varied with physician specialty (noninternist primary care, internal medicine, neurology, surgery), practice setting (nonmetropolitan versus small metropolitan or large metropolitan areas), and for carotid endarterectomy, region of the country (South, Central, Northeast, and West). The odds of carotid endarterectomy being reported as readily available were approximately 2.5 to 3.5 times greater for physicians practicing in the central, northeastern, and western regions compared with those practicing in the South, independent of practice setting and specialty. With regard to stroke prevention practices, 61% of physicians reported prescribing 325 mg of aspirin for stroke prevention, while 33% recommend less than 325 mg and 4% use doses of 650 mg or more. Seventy-one percent of physicians using warfarin reported monitoring anticoagulation with international normalized ratios, and 78% reported monitoring anticoagulated patients at least once a month. Fewer than 20% of physicians reported knowing the perioperative carotid endarterectomy complication rates at the hospital where they perform the operation themselves or refer patients to have the procedure done. CONCLUSIONS: Although all routine and most specialized services for secondary and tertiary stroke prevention are readily available to most physicians, variation in availability exists. The use of international normalized ratios for monitoring warfarin therapy has not yet become universal. Physician knowledge of carotid endarterectomy complication rates is generally lacking. Depending on their causes, these problems may be addressed through targeted physician education efforts and systematic changes in the way in which services are provided.     

Stacking interactions of ApA analogues with modified backbones

CD spectra have been measured as a function of temperature for a number of ApA analogues with modified backbones. Oligonucleotides with these modified backbones are being used as antisense agents having potential as viral therapeutics. Results of these studies show that when a carbonyl is substituted for the phosphate to produce an uncharged backbone, the analogues that have either sugar or morpholino substitution do not stack. In contrast, when a morpholino group is substituted for the sugar and the phosphate is modified so as to be uncharged, there is strong base stacking. Stacking interactions in the phosphorus-linked morpholino analogues are at least as strong as those found in d(ApA). The stacking interactions in ApA are weak by comparison. Singular value decomposition demonstrates that the stacking is two state, and Taylor series decomposition yields a coefficient that measures base stacking interactions. The van't Hoff equation is applied to the base stacking coefficient from the Taylor series fitting to give thermodynamic parameters.