White snakeroot poisoning in goats: Variations in toxicity with different plant chemotypes.

Tremetone and possibly other benzofuran ketones are believed to be the toxic compounds in white snakeroot. However, disease has not been reproduced with purified toxins and the concentrations of the benzofuran ketones in white snakeroot populations that cause toxicosis have not been documented. The objectives of this study were to compare the toxicity of seven plant populations, better characterize the clinical and pathologic changes of poisoning, and correlate intoxication with benzofuran ketone content. Four of the seven white snakeroot collections were toxic at the dose and duration used in the study. Affected goats became exercise intolerant, had significant serum enzyme changes and histological lesions in the large appendicular muscles. The incidence and severity of poisoning was not correlated with total doses of tremetone or total benzofuran ketone concentrations suggesting they may not be closely involved in producing toxicity and the possible involvement of an unidentified toxin. The results also demonstrate that white snakeroot populations vary chemically and toxicologically.

The role of the α7 subunit of the nicotinic acetylcholine receptor on motor coordination in mice treated with methyllycaconitine and anabasine.

The adverse effects of methyllycaconitine (MLA) have been attributed to competitive antagonism of nicotinic acetylcholine receptors (nAChR). Research has indicated a correlation between the LD50 of MLA and the amount of α7 nAChR in various mouse strains, suggesting that mice with more α7 nAChR require more MLA to be poisoned. However, recent research demonstrated that there was no difference in the acute lethality (LD50 ) to MLA in mice lacking the α7 nAChR subunit compared with wild-type mice. The objective of this study was to determine if the α7 nAChR subunit plays a role in motor coordination deficiencies that result from exposure to nAChR antagonists and agonists. We compared the motor function and coordination in wild-type mice to mice lacking the α7 subunit of the nAChR, after treating them with a non-lethal dose of MLA or anabasine, using the following tests: balance beam, grip strength, rotarod, open field and tremor monitor. Analysis of the data indicated that overall there was no difference between the wild-type and knockout mice (P = 0.39 for grip strength; P = 0.21 for rotarod; P = 0.41 for balance beam; P = 0.22 for open field; and P = 0.62 for tremors). Thus results from this study suggest that α7 nAChR does not play an integral role in the acute effects of MLA or anabasine on motor function/coordination. Consequently other subunits of nAChRs found in the neuromuscular junction are likely the primary target for MLA and anabasine resulting in motor coordination deficiencies and acute toxicosis.

Duodenal somatostatinoma presenting with complete somatostatinoma syndrome.

Somatostatinomas are the rarest pancreatic endocrine tumors and can arise in the pancreas or duodenum. Duodenal somatostatinomas are less common than, and are distinguished from, their pancreatic counterparts by a frequent association with type I neurofibromatosis, the presence of psammoma bodies, the less frequent presence of metastatic disease, and the absence of somatostatinoma syndrome (diabetes mellitus, steatorrhea, and cholelithiasis). We report a case of somatostatinoma with metastases and psammoma bodies presenting with all three features of the syndrome in a patient with neurofibromatosis. Although several reports have documented portions of the syndrome in patients with duodenal somatostatinomas, to our knowledge, this is the first report of the complete syndrome associated with a duodenal lesion.

Splenic abscess: report of six cases and review of the literature.

Splenic abscesses are rare but appear to be increasing in frequency. Recent advances in radiologic techniques have affected the diagnosis and management. The purpose of this study was to evaluate these effects. The medical records of one institution were retrospectively reviewed and six cases of splenic abscesses seen between 1989 and 1999 were identified. All patients had predisposing conditions with metastatic hematogenous infection in three and one each with trauma, immunodeficiency, and a contiguous site of infection. Fever was present in all patients with chills and vomiting in five and three patients, respectively. Left upper quadrant tenderness appeared in four patients and leukocytosis was found in every patient except one with the acquired immunodeficiency syndrome. Chest roentgenograms were abnormal in five patients with a left pleural effusion most common. Ultrasound revealed the defect in both patients it was utilized in and computed tomography was diagnostic in all cases. The causative organisms were anaerobes in two cases and Candida albicans, Streptococcus viridans, Escherichia coli, and Citrobacter freundii each present in one case. Radiology guided percutaneous drainage was attempted in four patients but was only successful in one. Splenectomy with antibiotics was curative in the remainder with a 100 per cent survival. These data suggest that percutaneous drainage may be appropriate for certain patients initially, but the high failure rate demonstrates that splenectomy remains the standard treatment.