Estimated compliance for removal of specified risk materials from 18 U.S. beef packing plants.

The removal of 18,345 specified risk materials was observed during audits of 18 U.S. beef processing facilities that, in total, account for over 90% of total U.S. beef slaughtered. Audited plants varied in capacity (280 to 6,000 head per day) and processed both "fed (young cattle)" and "nonfed (mature cows/bulls)" cattle. When all observations for removal of specified risk materials were combined from plants and adjusted for type of cattle processed, overall compliance with specified risk material removal regulations was 98.08%. A 100% compliance rate for removal of brains and distal ileums was recorded based on a total of 600 observations for removal of brains and a total of 2,400 observations for removal of distal ileums. Observations for removal of dorsal root ganglia were collected from 16 of the 18 plants, and overall compliance for dorsal root ganglia removal was 99.6% (4,783 of 4,800). Fifteen of the 16 plants were 100% compliant. For tonsils, data from 18 plants were collected, and tonsils were correctly removed from 92.8% (4,777 of 5,145) of tongues and heads. Data for spinal cord removal were collected from 18 plants, and the spinal cord was removed completely in line with U.S. Department of Agriculture-Food Safety and Inspection Service regulations for 99.43% of the observations. Based on the results of this study, packing plants have demonstrated that they are complying with regulations for removal of specified risk materials from beef meat products intended for human consumption greater than 98% of the time. To continue to assure food safety and consumer confidence, continued vigilance and provision of training programs for plant workers are essential.

Rupture of the aorta following road traffic accidents in the United Kingdom 1992-1999. The results of the co-operative crash injury study.

OBJECTIVE: The true incidence and survivability of blunt traumatic aortic rupture following road traffic accidents in the UK is unclear. The objective of this study was to determine the extent of blunt traumatic aortic rupture in the UK after road traffic accidents and the conditions under which it occurs. METHODS: Data for the study was obtained from the Co-operative Crash Injury Study database. Road traffic accidents that happened between 1992 and 1999 and included in the Co-operative Crash Injury Study database were retrospectively investigated. RESULTS: A total of 8285 vehicles carrying 14,435 occupants were involved in 7067 accidents. There were 132 cases of blunt traumatic aortic rupture, of which the scene survival was 9% and the overall mortality was 98%. Twenty-one percent of all fatalities had blunt traumatic aortic rupture (130/613). Twenty-nine percent were due to frontal impacts and 44% were due to side impacts. Twelve percent of the blunt traumatic aortic rupture cases in frontal vehicle impacts were wearing seat belts and had airbag protection and 19% had no restraint mechanism. The Equivalent Test Speed of the accident vehicles, (where equivalent test speed provides an estimate of the vehicle impact severity and not an estimate of the vehicle speed at the time of the accident), ranged from 30 to 110 km/h in frontal impacts and from 15 to 82 km/h in side impacts. CONCLUSION: Blunt traumatic aortic rupture carries a high mortality and occurred in 21% of car occupant deaths in this sample of road traffic accidents. Impact scenarios varied but were most common from the side. The use of an airbag or seat belt does not eliminate risk. The injury can occur at low severity impacts particularly in side impact.

An oligopeptide of the feline leukemia virus envelope glycoprotein is associated with morphological changes and calcium dysregulation in neuronal growth cones.

Neuropathogenic processes that affect the pathfinding properties of neuronal growth cones could account for many of the dysfunctions unique to retroviral infection of developing nervous systems. Pediatric HIV-1 infection, for example, is associated with a distinctive neuropathogenesis that includes marked cortical atrophy, cognitive disorders, and pyramidal dysfunction. The ability of HIV's envelope glycoprotein, gp120, to produce increased intracellular free calcium ([Ca2+]i) leading to neuronal death has been documented. We hypothesize that gp120 and the envelope glycoproteins of other retroviruses may have similar calcium-increasing effects in advancing growth cones, a property which could disrupt the orderly development of the nervous system. To explore this possibility, we exposed chick ciliary ganglion neurons in culture to a known cytopathic region (CVR5) of the feline leukemia virus' envelope glycoprotein. CVR5 produced [Ca2+]i increases and dose-dependent morphological changes in growth cones isolated from their cell bodies by axotomy. These responses of growth cones to CVR5 suggest that the neurotoxic effects of retroviruses could be mediated at the level of the individual growth cone through exposure to envelope glycoproteins and could constitute one mechanism by which these viruses perturb the normal development of the nervous system.

Statistical comparison of power spectra: a computer program.

A general computer program, of interest to neurobiologists, for comparison of uncorrelated power spectra is presented. The program, ALPHAF, is written in Fortran V language and is easily compiled and executed in any computer with a Fortran software package. The purpose of the program is to read power spectral density (PSD) values into a computer from digital tape and then perform the following functions: (1) compute and report power; (2) compute and report averages of the computed power values over selected frequency bands and (3) compute and report statistical standardised normal distributions for a frequency spectrum of interest. The standardised normal distribution statistic is derived by using equation 7.20, page 250 of Random data: Analysis and measurement procedures (Bendat and Piersol, 1971).