RESUMEN
Eight compounds were isolated from the ethyl acetate fraction of the 80% aqueous ethanol extract of the roots and stems of Rubus pirifolius Smith by AB-8 macroporous resin, silica gel, ODS, Sephadex LH-20 column chromatography, and semi-preparative HPLC. Their structures were identified by spectral analysis such as 1D/2D NMR, MS, UV, IR and by comparison with literature information as rubussecotriterpene A (1), rubussecotriterpene B (2), cecropiacic acid (3), cecropiacic acid 3-methyl ester (4), alphitolic acid (5), betulinic acid (6), betulin (7), and obtusalin (8). Compounds 1 and 2 are new compounds, and compounds 3-8 were isolated from this plant for the first time.
RESUMEN
<p><b>OBJECTIVE</b>To elucidate the molecular mechanism of X-linked adrenoleukodystrophy(ALD) in Chinese.</p><p><b>METHODS</b>Polymerase chain reaction in exon 1, exon 5 and their flanking sequences and direct DNA sequencing of ALD gene were performed in four patients, their mothers and twenty normal individuals as controls.</p><p><b>RESULTS</b>A splice mutation was identified in the interface of exon 5 and intron 5 (1875 G-->A). This splice mutation in 5' end of intron 5 might lead to abnormal splice in exon 5 and exon 6 and bring about unstable and abnormal ALD protein; the lignoceryl CoA ligase could not transport very long chain fatty acids (VLCFA) into peroxisome and could not function normally; consequently, defective beta-oxidation of VLCFA in peroxisome could result in an accumulation of VLCFAS in the central nervous system, adrenal gland and blood.</p><p><b>CONCLUSION</b>The splice mutation in 5' end of intron 5 leading to abnormal splice in exon 5 and exon 6 appears to be one of the causes of X-linked recessive adrenoleukodystrophy.</p>