Effect of clenbuterol on tracheal mucociliary transport in horses undergoing simulated long-distance transportation.

BACKGROUND: Pneumonia is observed in horses after long-distance transportation in association with confinement of head position leading to reduction in tracheal mucociliary clearance rate (TMCR). HYPOTHESIS/OBJECTIVES: Clenbuterol, a beta-2 agonist shown to increase TMCR in the horse, will ameliorate the effects of a fixed elevated head position on large airway contamination and inflammation in a model of long-distance transportation model. ANIMALS: Six adult horses. METHODS: A cross-over designed prospective study. Horses were maintained with a fixed elevated head position for 48 hours to simulate long-distance transport, and treated with clenbuterol (0.8 µg/kg PO q12h) or a placebo starting 12 hours before simulated transportation. TMCR was measured using a charcoal clearance technique. Data were collected at baseline and 48 hours, and included TMCR, tracheal wash cytology and quantitative culture, rectal temperature, CBC, fibrinogen, and serum TNFα, IL-10, and IL-2 levels. There was a 18-21 day washout between study arms, and data were analyzed using regression analysis and Wilcoxon rank-sum tests. RESULTS: Tracheal mucociliary clearance rate was significantly decreased after transportation in both treatment (P = .002) and placebo (P = .03) groups. There was a significant effect of treatment on TMCR, with the treatment group showing half the reduction in TMCR compared with the placebo group (P = .002). Other significant differences between before- and after-transportation samples occurred for serum fibrinogen, peripheral eosinophil count, quantitative culture, tracheal bacteria, and degenerate neutrophils, though no treatment effect was found. CONCLUSIONS AND CLINICAL IMPORTANCE: Treatment with clenbuterol modestly attenuates the deleterious effects of this long-distance transportation model on tracheal mucociliary clearance.

Clinical features of early-onset Alzheimer disease in a large kindred with an E280A presenilin-1 mutation.

OBJECTIVES: To characterize clinical features of a very large pedigree with early-onset Alzheimer disease (AD) in which all affected individuals carry the identical glutamic acid-to-alanine mutation at codon 280 in the presenilin-1 gene. DESIGN: Clinical histories were obtained by patient and family interviews and through medical or civil records. Using standard diagnostic criteria, a case series of 128 individuals was identified, of which 6 have definitive (autopsy-proven) early-onset AD, 93 have probable early-onset AD, and 29 have possible early-onset AD. SETTING: Community based in Antioquia, Colombia. PATIENTS: A population-based sample in which all members of 5 extended families (nearly 3000 individuals) were surveyed. Criteria for inclusion required obtaining sufficient information to categorize the individual as affected. MAIN OUTCOME MEASURES: Age at onset, neuropsychological profile, neurologic history, and examination. RESULTS: The patients had a mean age at onset of 46.8 years (range, 34-62 years). The average interval until death was 8 years. Headache was noted in affected individuals significantly more frequently than in those not affected. The most frequent presentation was memory loss followed by behavior and personality changes and progressive loss of language ability. In the final stages, gait disturbances, seizures, and myoclonus were frequent. CONCLUSIONS: Other than the early onset, this clinical phenotype is indistinguishable from sporadic AD except that affected individuals frequently complained of headache preceding and during the disease. Despite the uniform genetic basis for the disease, there was significant variability in the age at onset, suggesting an important role for environmental factors or genetic modifiers in determining the age at onset.

Oedema disease in chickens caused by Mexican poppy (Argemone mexicana) seed.

Ground Mexican poppy (Argemone mexicana) seed produced growth depression, oedema and death when fed at 1% and 3% of a basal ration to day-old, layer strain, cockerel chickens. The mortality rate was increased by raising the sodium chloride content of the basal ration from 0.18% to 1.68%. Clinical signs consisted of subcutaneous oedema, a high pitched chirp and terminal gasping. Hydropericardium, oedema of the lungs, and subcutaneous oedema of the thorax, abdomen, wings, neck and throat were the major lesions. Foci of calcificaton were present in the ventricular myocardium of some chickens fed 3% A. mexicana.