Parathyroid adenomas evaluated by Tl-201/Tc-99m pertechnetate subtraction scintigraphy and high-resolution ultrasonography

Thallium-201/technetium-99m pertechnetate subtraction scintigraphy of the parathyroid glands was performed in a prospective study of 33 patients who had undergone bilateral neck exploration for elevated serum calcium and serum parathyroid hormone levels. In 31 cases, the Tl-201/Tc-99m subtraction technique yielded an overall sensitivity of 81%, specificity of 99%, and accuracy of 94% for identifying solitary parathyroid adenomas. Tl-201/Tc-99m subtraction scintigraphy correctly identified 73% of parathyroid adenomas weighing less than 499 mg, 79% of those weighing 500-1,499 mg, and 100% of adenomas weighing more than 1,500 mg. In a subgroup of 24 patients with solitary parathyroid adenomas who underwent both scintigraphy and high-resolution sonography, the sensitivity, specificity, and accuracy of both procedures were similar.     

Norovirus and foodborne disease, United States, 1991-2000

Efforts to prevent foodborne illness target bacterial pathogens, yet noroviruses (NoV) are suspected to be the most common cause of gastroenteritis. New molecular assays allow for better estimation of the role of NoV in foodborne illness. We analyzed 8,271 foodborne outbreaks reported to the Centers for Disease Control and Prevention from 1991 to 2000 and additional data from 6 states. The proportion of NoV-confirmed outbreaks increased from 1% in 1991 to 12% in 2000. However, from 1998 to 2000, 76% of NoV outbreaks were reported by only 11 states. In 2000, an estimated 50% of foodborne outbreaks in 6 states were attributable to NoV. NoV outbreaks were larger than bacterial outbreaks (median persons affected: 25 versus 15), and 10% of affected persons sought medical care; 1% were hospitalized. More widespread use of molecular assays will permit better estimates of the role of NoV illness and help direct efforts to control foodborne illness.     

The Effects of Propranolol and Amitriptyline on Vascular and EMG Biofeedback Training

SYNOPSIS
Biofeedback training for vascular and neuromuscular (EMG) control has been used for the treatment of migraine, chronic muscle contraction headaches, and myofascial pain syndromes. Many patients undergoing this training are concurrently taking propranolol, a beta blocker, and/or amitriptyline, a tricyclic antidepressant which inhibits re-uptake of serotonin. There is an extreme paucity of information delineating the effects and interactions of these medications in patients learning autonomically mediated vascular control through biofeedback. In this pilot study we examined the ability of patients to learnvascular control and neuromuscular control. Four groups of patients were used: those taking no medication, those taking propranolol or amitriptyline alone, and patients using both medications. Results indicate the use of propranolol in patients learning vascular control produces a markedly increased variability in the ability of patients to control physiological parameters; this difficulty is also manifested in EMG training of patients taking only amitriptyline. Those within group variances were found to be negated by the use of both medications together. In spite of these findings, all groups did reach training criterion. In some patients the inability to easily control baseline physiological parameters may induce enough frustration to cause premature termination of training. It is postulated that the effectiveness of biofeedback training might be enhanced in patients not concurrently taking medications with autonomic effects.     

Biological transmission of vesicular stomatitis virus (New Jersey serotype) by Simulium vittatum (Diptera: Simuliidae) to domestic swine (Sus scrofa)

The role of hematophagous arthropods in vesicular stomatitis virus (New Jersey serotype; VSV-NJ) transmission during epizootics has remained unclear for decades in part because it has never been shown that clinical or subclinical disease in a livestock host results from the bite of an infected insect. In this study, we investigated the ability of VSV-NJ-infected black flies (Simulium vittatum Zetterstedt) to transmit the virus to domestic swine, Sus scrofa L. Experimental evidence presented here clearly demonstrates that VSV-NJ was transmitted from black flies to the swine. Transmission was confirmed by seroconversion or by the presence of clinical vesicular stomatitis followed by seroconversion. Our results represent the first report of clinical vesicular stomatitis in a livestock host after virus transmission by an insect.