Identification of geranic acid, a tyrosinase inhibitor in lemongrass (Cymbopogon citratus).

Lemongrass is a popular Asian herb having a lemon-like flavor. Very recently, potent tyrosinase inhibitory activity has been found in lemongrass in addition to various biological activities reported in the literature. The aim of the present study is to identify the active compounds in the lemongrass. An assay-guided purification revealed that one of the active substances was geranic acid. Geranic acid has two stereoisomers, which are responsible for the trans and cis geometry on the conjugated double bond. Both isomers are present in the active ethyl acetate-soluble extract of the lemongrass, and their IC50 values were calculated to be 0.14 and 2.3 mM, respectively. The structure requirement of geranic acid for the potent tyrosinase inhibitory activity was investigated using geranic acid-related compounds.

IgA-associated glomerulonephritis with membranoproliferative glomerulonephritis-like pattern in two children.

In this article, we report two patients with IgA-associated glomerulonephritis with a membranoproliferative glomerulonephritis (MPGN) -like pattern. Both patients had nephrotic syndrome at onset. One patient was treated with high-dose alternate-day prednisolone (PSL), and the other with indomethacin and low-dose PSL. One lost the urinary abnormalities 3 years after starting treatment. The other lost the nephrotic state and hematuria over a 5-year period, but proteinuria persisted until the last follow-up. Both patients had diffuse proliferative changes with mesangial interposition and subendothelial deposits, associated with strongly positive deposits of C3 and IgA along the capillary walls of the glomeruli. These two patients showed histological changes compatible with type-I MPGN, but the pattern of IgA deposits was not typical of idiopathic MPGN or IgA nephropathy. We assume this is a rare form of MPGN, not associated with liver disease or other systemic diseases.

Transthoracic Doppler assessment of coronary flow velocity reserve in children with Kawasaki disease: comparison with coronary angiography and thallium-201 imaging.

OBJECTIVES: The purpose of this study was to determine the feasibility of coronary flow velocity reserve (CFVR) measurement by transthoracic Doppler echocardiography (TTDE) in children with Kawasaki disease (KD). BACKGROUND: Doppler-derived CFVR is a reliable marker predicting the presence of myocardial ischemia. METHODS: We studied 49 patients (median age 11 years) with KD. The CFVR was calculated as the ratio of hyperemic to basal peak (peak CFVR) and mean (mean CFVR) diastolic flow velocities in the posterior descending coronary artery (PD) and left anterior descending coronary artery (LAD). The CFVR measurements by TTDE were compared with the results of coronary angiography, thallium-201 (Tl-201) single-photon emission computed tomography (SPECT), and intracoronary Doppler study. RESULTS: The CFVR measurements by TTDE were obtained in 92 (94%) of 98 vessels of the PD and LAD in 49 study patients. Both peak and mean CFVRs for 21 stenotic vessels were significantly smaller than those for 35 normal vessels and for 20 vessels with aneurysmal lesions (p < 0.0001). Peak and mean CFVR <2.0 predicted significant coronary stenosis, as determined by coronary angiography, with sensitivities and specificities of 89% and 96% and 89% and 97%, respectively. Also, both peak and mean CFVRs were correlated with reversible perfusion defects on Tl-201 SPECT (agreement 80%; kappa 0.4). The correlation between peak and mean CFVRs determined by the TTDE and intracoronary Doppler studies in 36 vessels of 23 patients were 0.76 and 0.80, respectively. CONCLUSIONS: The CFVR measured by TTDE predicts the presence of significant coronary stenosis of either the right coronary artery or LAD, as well as myocardial ischemia of these territories in children with KD.