Use of enzyme-linked immunoassays for antibody to types C and D botulinum toxins for investigations of botulism in cattle.

The development of specific enzyme-linked immunosorbent assays (ELISA) for antibody to types C and D Clostridium botulinum toxins for investigation of botulism in cattle is described. Partially purified type C and D toxins were used as antigens to develop these ELISAs. Specificity of the ELISAs was evaluated on sera from 333 adult beef and dairy cattle from areas with no history or evidence of botulism in animals or water birds. The test was also evaluated on sera from 41 herds that included herds vaccinated against botulism, confirmed botulism cases and herds from areas where the disease is considered endemic. The ELISAs detected the presence of antibody to botulinum toxins in samples from vaccinated cattle and both convalescent and clinically normal animals from unvaccinated herds with outbreaks of botulism. Antibody was also found in unvaccinated animals from herds in which there had been no diagnosed botulism cases in areas where botulism was considered endemic. Sera from some unvaccinated cattle with high ELISA reactivity was shown to be protective for mice in botulinum toxin neutralisation tests. The use of these tests in investigations of botulism in cattle is discussed.

18F positron emission computed tomography in closed head injury.

Locus and extent of cerebral dysfunction in five closed head injured patients as inferred from positron emission tomography (PET) and computed tomography (CT) scan studies were compared with locus and extent inferences made in the same five patients using three additional independent sources of data. These data included: (1) clinical neurologic examination findings, (2) an extensive battery of neuropsychologic tests (including WAIS, Wechsler Memory, Halstead Reitan procedures), and (3) a comprehensive speech and language assessment battery (including the Boston Diagnostic Aphasia Examination (BDAE) and the Token Test). Neurologic, psychologic, and speech examinations were conducted within one week of the PET and CT studies. Three patients were studied at three months, one patient at six months, and one patient at two years after head injury. Follow-up CT scans were done 14 months later on four of five patients. This study supported the following major conclusions: the PET findings closely correspond with the site and extent of cerebral dysfunction inferences derived from the neurologic and behaviorial examinations but the CT findings did not; the follow-up CT scans, however, showed structural abnormalities (ie, encephalomalacia and atrophy) that were consistent with the PET, neurologic examination, and behavioral assessment findings; the study strongly supports the validity and predictive utility of neurobehavioral data which are directly pertinent to rehabilitation planning/programming in patients with closed head injury.