VALIDATION OF A SUBENDOCARDIAL ISCHAEMIC SHEEP MODEL BY INTRACORONARY FLUORESCENT MICROSPHERES

1. We evaluated the use of non-radioactive fluorescent-labelled microspheres (FM) for the measurement of regional myocardial blood flow (RMBF) in an ischaemic sheep model. 2. Injection of FM directly into the coronary artery was compared with left atrial injection. There was a good correlation in the measurement of RMBF between these two injection methods (r = 0.92; n= 107 data points). Injection into the coronary artery requires less FM (one twentieth of that required by atrial injection) and is more economical. 3. The use of a fluorescent technique without filtering myocardial tissue was investigated. Calibration curves from the fluorescence plus myocardial tissue samples were similar to those of the pure fluorescence samples and both showed a linear relationship between fluorescent intensity and the number of microspheres (r > 0.97). These results indicate that the extraction of six fluorescent dyes (blue-green, yellow-green, green, orange, red and crimson) directly from the aqueous solution using ethyl acetate is effective. 4. A subendocardial ischaemic model was produced by partially occluding the circumflex artery (CxA) with concomitant left atrium (LA) pacing. During ischaemia, the endocardium/epicardium (Endo/Epi) flow ratios in the ischaemic area changed from 1.04 ± 0.12 to 0.47 ± 0.17 (P < 0.05; CxA injection) and from 1.08 ± 0.12 to 0.51 ± 0.05 (P < 0.05; LA injection). The ratio in the non-ischaemic area remained unchanged (1.12 ± 0.26 to 1.01 ± 0.22; not significant). 5. RMBF calculation using coronary inflow as the reference flow was also compared with that using the traditional method. We found that, in this study in which a non-filtering technique was applied, using coronary inflow as the reference flow was superior to the conventional distal sampling method.     

柱前荧光标记高效液相色谱法对血浆中l-麻黄碱和d-伪麻黄碱的定量分析

l-麻黄碱和d-伪麻黄碱是生药麻黄中早为人知而至今仍被广泛用于临床的一对手性异构生物碱。由于二者为生药麻黄中的主要成分但药理活性不同,为便于临床监控及有效用药,高分辨高灵敏度的检测方法的开发迫在眉睫。本文以易于得到的dansylchloride为柱前荧光标识试剂,在确定了最佳衍生化及分离条件的基础上,建立了理想的色谱分析系统(线性检测范围1～800ng·ml^-1)。同时运用此方法,完成了对静注l-麻黄碱和d-伪麻黄碱后豚鼠血浆内该对手性异构体水平的考查,并且定量检测了服用中成药小青龙合剂后人血浆中的该对手性异构体。     

Pachygyriclike changes: topographic appearance at MR imaging and CT and correlation with neurologic status

Studies of 23 pediatric patients with pachygyriclike changes (PLCs) examined with computed tomography (CT) and magnetic resonance (MR) imaging were reviewed to determine topographic patterns and correlate them with various clinical syndromes and degrees of neurologic impairment. Three types of topographic distributions were identified: unilateral, diffuse, and bilateral nondiffuse (of which eight of 10 showed frontotemporal predominance). PLCs were an isolated finding in seven patients, were associated with various congenital syndromes in nine patients, and were associated with congenital infection in seven patients, six of whom showed marked white matter abnormalities. Although most patients had severe developmental delay, three with nondiffuse PLCs had less severe impairment, permitting less required care.     

Isolation of intestinal spirochaetes from homosexuals

Spirochaetes were isolated from rectal swabs of two homosexuals and the faeces of a third, using simple isolation techniques not previously applied to specimens of this type. The ease of culture of these organisms will enable their distribution and pathogenicity to be studied, particularly in relation to their significance in homosexuals.