[Lipid metabolism in idiopathic pulmonary fibrosis].

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease of unknown etiology, which was characterized by irreversible lung function decrease and high mortality. Up till now, only two drugs, i.e. Pirfenidone and Nintedanib,have been approved by Food and Drug Administration (FDA) for therapy of IPF, and the treatment is less effective. Therefore, it is urgent to develop new therapeutic drugs. In recent years, studies had paid attention to lipid metabolism in IPF. In this review, we discussed recent major advances of lipid metabolism, biomarkers and clinical trials in IPF.

Estimation of nitrification rates in flooded soils.

Three techniques for estimating nitrification rates in flooded soils were evaluated in short-term incubation experiments using three soils. The techniques were based on inhibition of either ammonium or nitrite oxidation and (13)N isotope dilution. Of four inhibitors of ammonium oxidation evaluated, one (allylthiourea) was ineffective and two (2-ethynylpyridine or phenyl acetylene dissolved in ethanol) promoted immobilization of ammonium. Emulsified 2-ethynylpyridine and acetylene were equally effective inhibitors of ammonium oxidation and had little or no effect on gross rates of N mineralization and immobilization. Four inhibitors of nitrite oxidation were evaluated, but this approach was compromised by the nonspecificity of three of the compounds-potassium cyanide, 2-ethylamino-4-isopropylamino-6-methylthio-s-triazine (ametryne) and 3-(3,4-dichlorophenyl)-1-methylurea (DMU)-and by the partial effectiveness of another (potassium chlorate). Two methods based on isotope dilution gave similar estimates of nitrification rates. These rates were similar to those estimated by inhibition of ammonium oxidation in one soil but were lower in the other two soils. In the latter two soils, nitrification of labeled ammonium derived from dissimilatory nitrate reduction resulted in underestimation of nitrification rates by isotope dilution.