Montserrat volcanic ash induces lymph node XXXX and @entity55 .

@entity32 @entity82 @entity738 @entity55 @entity1219 @entity3440 @entity35 @entity70967
OBJECTIVES: A substantial amount of Montserrat volcanic ash, containing up to 24% of @entity3440 (w/w), a fibrogenic crystalline @entity3440 , has been generated since the first documented eruption in 1995. The bioreactivity of the ash and its two major components: @entity3440 and anorthite have been studied in vivo for a year following intratracheal instillation into @entity35 . METHODS: The @entity35 (n=5) were instilled with a sterile vehicle solution (0.15 M @entity1219 ) and/or three doses (1.0, 2.5 or 5.0 mg) of each of the dust, and were sacrificed at 13, 25 or 49 weeks post-instillation for quantitative biochemical and histopathological analyses in the lung and lymph nodes. RESULTS: @entity3440 caused @entity32 in the lung and @entity738 in the hilar lymph nodes associated with significant size augmentation at 13 weeks post-instillation (P<0.05) and @entity3440 (5.0 mg) induced @entity82 in the lung at 49 weeks post-exposure. However, the Montserrat volcanic ash caused @entity32 in the lung at 49 weeks post-treatment without any fibrogenic response although the ash (5.0 mg) triggered significant lymph node enlargement without significant changes in the lung at 13 weeks post-treatment (P<0.05). Dose and time independent responses in the @entity70967 -exposed lung and lymph nodes suggest that a single instillation of 5.0 mg of poorly soluble mineral dust does not induce any change in the lung or lymph nodes. CONCLUSION: The ash produces inflammatory reactions in lymph nodes at 13 weeks post-instillation in @entity35 . These effects are seen much earlier than any inflammatory reaction in the lung. The onset of the @entity55 is delayed until 49 weeks post-exposure. Despite the high @entity3440 content of the ash, there is no evidence of any lung fibrogenic responses.
