Hangman's fracture resulting from improper seat belt use.

Diagonal seat belt application without accompanying lap belt closure may produce severe cervical spine injuries, including hangman's fracture and decapitation. Seat belts are effective in reducing injury, but they must be worn properly to do so. Passive restraint systems involving a diagonal seat belt may be hazardous if the motorist does not use the accompanying lap belt. We have presented a case in which the driver in a motor vehicle accident sustained a hangman's fracture (bilateral fracture of the pedicles of C-2) caused by use of a diagonal seat belt without accompanying lap belt closure. The mechanism of injury, as classically described in judicial hanging, is hyperextension and distraction, which occurred when the victim "submarined" under the diagonal seat belt and was caught at the neck.

Current management of the poisoned patient.

Management of the poisoned patient is a common and difficult problem for many practitioners. I present a clinical approach to the management of these patients, with emphasis on recent advances and controversies. Efficacy of gastric emptying, activated charcoal, manipulation of urinary pH, and indications for dialysis are discussed. Poisonings for which specific antidotes are available are reviewed.

Long-term effect of 2-hydroxyethyl retinamide on urinary bladder carcinogenesis and tumor transplantation in Fischer 344 rats.

The effects of HER upon early and late stages of BBN-induced bladder cancer in rats were examined. Female Fischer 344 rats were administered HER in the diet either before and during or continuously after BBN administration and were monitored periodically for up to 2 years. The total dose of BBN was 600 mg administered over a 6-week period. In a separate experiment, the effects of HER administration to syngeneic recipients of a transplanted primary bladder cancer were examined. No effects on neoplastic development were observed as the result of HER treatment before and during carcinogen administration. However, at the 1-year sacrifice, there was a significant increase in bladder tumor incidence in the animals receiving BBN followed by continuous retinoid treatment versus animals receiving BBN only. At the 2-year sacrifice, there was a significant increase in tumor progression in the continuous retinoid group versus the animals receiving BBN alone, based upon grading and staging of tumors, although tumor incidences were not significantly different. In the transplantation experiment, more recipients (9/20 versus 2/20) receiving continuous HER had large, anaplastic tumors following 9 months of observation than did control animals. This study supports the view that retinoids should not be considered as only inhibitors of carcinogenesis, but rather as modifiers which vary in their effects depending upon factors yet to be understood.

Haematology and pathology of captive southern grasshopper mice (Onychomys torridus).

A colony of Onychomys torridus was evaluated for the prevalence of infectious, parasitic and congenital diseases. Multiple limb defects including brachydactyly, syndactyly, and hemimelia were observed in offspring from the colony. The colony was parasitized by Ornithonyssus bacoti (tropical rat mites) on 2 occasions. No infectious diseases were detected. Normal haematologic values were determined in healthy adult animals.

Severe central nervous system damage and profound acidosis in persons exposed to pentaborane.

Three cases of pentaborane intoxication resulting from a common exposure are presented. These cases were characterized by the rapid onset of seizures and opisthotonic spasms accompanied by severe metabolic acidosis without respiratory compensation. Rhabdomyolysis occurred, serum transaminase levels were elevated, and liver damage was demonstrated histologically. One patient died and another sustained severe neurologic damage. These poisonings are unique with respect to the rapid and devastating neurologic consequences. Pentaborane is an extremely toxic compound and a major hazard not only to exposed workers but also to the medical personnel dealing with them.

Intestinal parasites of the free-ranging Cayo Santiago rhesus monkeys (Macaca mulatta).

Free-ranging rhesus macaques on the island of Cayo Santiago, Puerto Rico, were surveyed for intestinal parasites for the first time in over 40 years. Results were compared with the only previous study, and the relationships between the prevalence of Strongyloides and dominance rank, body weight, age, and matriline examined in the sampled population.

Experience with a multidisciplinary emergency medicine clerkship.

In 1979 a required emergency medicine clerkship was added to the senior curriculum at the Medical College of Virginia. Coordinated by the Department of Surgery but receiving active support from other disciplines, the emergency medicine clerkship combined clinical participation in emergency care with a balanced academic program of lectures, conferences, and advanced cardiac life-support training. The program evolved into a popular and productive experience and stimulated positive changes in the emergency unit at other levels.

Isoniazid overdose treated with high-dose pyridoxine.

Large doses of pyridoxine recently have been shown to prevent the seizures and acidosis caused by ingestion of more than two to three grams of isoniazid. We present three cases of massive isoniazid ingestion, producing seizures and acidosis, that were treated successfully by administration of one gram of pyridoxine intravenously for each gram of isoniazid ingested.

Toxicity of cecal filtrates from guinea pigs with penicillin-associated colitis.

Lethal enterocolitis was induced in guinea pigs by intramuscular injection of penicillin. The presence of filterable toxic substance in the cecal contents of penicillin-treated guinea pigs was demonstrated. The toxin was heat-labile and produced enterosorption activity in rabbit intestinal loops and morphologic changes in Y-1 adrenal cell cultures. The cecal filtrates were lethal for mice when injected intraperitoneally and lethal for guinea pigs when injected intraperitoneally or intracecally. Cecal filtrates from saline-treated guinea pigs were not lethal to experimental animals. Filtrates prepared from broth cultures of cecal contents from penicillin or saline-treated guinea pigs also showed the presence of a lethal toxic substance. The study demonstrated that bacteremia is minimal, nonspecific and probably a terminal event in penicillin-associated deaths in guinea pigs.