Broad-beta disease versus endogenous hypertriglyceridemia: levels and lipid composition of chylomicrons and very low density lipoproteins during fat-free feeding and alimentary lipemia.

To assess the roles of endogenous and exogenous lipid in the production of the abnormal lipoprotein patterns characteristic of broad-beta desease (with a type IVIII lipoprotein pattern) and endogenous hypertriglyceridemia (with a type IV pattern), oral fat loads (50 g/M-2) were administered to six subjects with broad-beta disease and to eight with endogenous hypertriglyceridemia following at leat 72 hr of 0% fat, 85% carbohydrate isocaloric formula feeding. Total plasma and Sf greater than 400, 100-400, 60-100, 30-60, and 20-30 lipoprotein cholesterol, triglyceride, and phospholipid levels were measured at 0 hr, 6 hr (at or before the peak of alimentary lipemia), and 24 hr following the fat load. Following fat-free feeding the levels and composition of the endogenous Sf greater than 400 lipoproteins were similar in both disorders; whereas total Sf20-400, and most notably, Sf 30-60 and 20-30 levels were increased and enriched in cholesterol in the subjects with broad-beta disease.     

Perfusion of the cervical spinal cord in situ of adult rats using a perfluorocarbon emulsion

A method was developed for the perfusion of the cervical spinal cord of adult rats through the supplying arteries. A medium containing perfluorotributylamine as an oxygen carrier was used. The electrophysiological responsiveness was continuously monitored; pO₂, pCO₂, pH, Na⁺ and K⁺ were intermittently measured in the medium. The perfused cord maintained its responsiveness for more than 5 h. No changes in its structure became apparent in electron micrographs.     

Differences in tocopherol-lipid ratios in ARDS and non-ARDS patients

Plasma tocopherol, plasma total lipid levels and tocopherol-lipid ratio were measured every 6 h during 48 h in 12 critically ill patients and compared with those of a control group. The patients were divided into two groups. Group I comprised 6 critically ill patients with ARDS and group II comprised 6 severely ill patients without ARDS. The means for all observations of plasma tocopherol, total lipid levels and tocopherol-lipid ratio in groups I and II were significantly depressed relative to a control group (p<0.0001). The difference in the average tocopherol-lipid ratio between the three groups (p<0.0001) and between the groups I and II was statistically significant (p<0.0001). Our results indicated: (1) a decrease of vitamin E concentrations in the critically ill patients, particularly in ARDS patients; (2) the importance of the relationship between plasma tocopherol and plasma lipids levels in evaluating the deficiency in vitamin E which was evident in ARDS patients.     

In vivo evidence for alpha 2-adrenergic-dependent inhibition of lipid mobilization in the rabbit

Both alpha- and beta-agonists were infused i.v. in unanesthetized rabbits. The alpha-adrenergic effect on lipid mobilization was investigated by comparing the modifications of blood glycerol levels induced by clonidine (alpha 2-agonist) and amidephrine (alpha 1-agonist) alone or in combination with isoprenaline (beta-agonist). Clonidine (2 micrograms X kg-1 X min-1) was found to significantly reduce the basal or isoprenaline-stimulated glycerol levels whereas amidephrine (10 micrograms X kg-1 X min-1) was without any effect. Plasma IRI levels were also reduced by clonidine. The results suggest that the reduction of lipid mobilization produced by clonidine could have been the consequence of the stimulation of the alpha 2-adrenergic antilipolytic receptors previously shown to be present in isolated fat cell membranes.     

牛初乳脂质营养液用于严重烫伤大鼠的研究

目的：探索牛初乳脂质营养液用作烫伤病人营养增补剂的可能性。方法：分析了烫伤大鼠服用牛初乳脂质营养液第９天和２５天时血浆中脂溶性维生素、β－胡萝卜素、ＳＯＤ和ＬＰＯ的水平，作了烫伤动物的常规观察和存活率测定。结果：服用营养液能显著升高与生物体内抗氧化作用有关的脂溶性维生素，β－胡萝卜素和ＳＯＤ的水平，降低对生物体有害的ＬＰＯ的含量，明显提高烫伤动物的存活率。结论：该营养液可用作烫伤病人综合治疗的营养增补剂。     

Colour Doppler signal enhancement of intrarenal vasculature of the rabbit with Perflubron

The colour Doppler signal enhancement of the intrarenal vasculature of the kidney was studied after intravenous infusion of Perflubron. This enhancement was evaluated qualitatively and semi-quantitatively. Nine rabbits received 1 g/kg of a 100% w/v Perflubron emulsion [perfluorooctylbromide (PFOB), Alliance Pharmaceutical] intravenously. Then, two groups of 2 rabbits received 2 and 3 g/kg respectively, and 1 rabbit received 4 g/kg. The kidneys were imaged longitudinally on a colour Doppler unit with a 7.5 MHz transducer. Signal enhancement was evaluated semi-quantitatively by counting the levels of signal threshold that had to be subtracted to reproduce the baseline image. This measurement was performed 1, 3, 5, 10, 30, 45, 60, 90 and 120 min after infusion. We found that detection of very small vessels deep into the parenchyma was possible with Perflubron. In the group that received 1 g/kg Perflubron significant variations in signal enhancement were noted. The curve of mean signal enhancement showed a maximum Doppler signal at about 15 min, which slightly and progressively decreased during the next hour. With the 2, 3 and 4 g/kg doses, enhancement was constant and proportional to the infused dose. Perflubron emulsion allows significant Doppler enhancement on colour flow imaging, providing better visualisation of deep parenchymal small vessels. A dose of 1 g/kg seems adequate for this purpose.Correspondence to: N. Grenier     

抗氧化酶及脂质过氧化物在肾移植中的意义

检测同种异体肾移植患者的血清抗氧化酶，包括超氧化物歧化酶和谷胱甘肽过氧化物酶及脂质过氧化物的降解产物丙二醛的动态变化。以了解了其在肾缺血－再灌注损伤中的作用。     

ATP-MgCl_2对烫伤大鼠肠粘膜保护作用的实验观察

为研究 ATP-MgCl_2对创伤应激动物肠粘膜的保护作用,采用30%TBSAⅢ度烫伤大鼠模型,观察了腹腔注射 ATP-MgCl_2复合液对回肠粘膜丙二醛(MDA)含量及回肠组织形态学改变的影响。结果显示:烫伤后6～24小时,MDA 含量明显升高,并伴有形态学病理改变。经 ATP-MgCl_2注射治疗的大鼠伤后24小时内 MDA 含量维持于正常对照水平,且回肠粘膜病理改变减轻。提示:ATP-MgCl_2能够保护烫伤大鼠肠粘膜,其作用机理可能与降低肠粘膜的脂质过氧化反应有关。     

Pergolide scavenges both hydroxyl and nitric oxide free radicals in vitro and inhibits lipid peroxidation in different regions of the rat brain

The free radical hypothesis for the pathogenesis and/or progression of Parkinson's disease (PD) has gained wide acceptance in recent years. Although it is clear that dopamine (DA) agonists cannot completely replace levodopa therapy, they can be beneficial early in the course of PD by reducing the accumulation of DA which undergoes auto-oxidation and generates cytotoxic free radicals. In the present study we demonstrate that pergolide, a widely used DA agonist, has free radical scavenging and antioxidant activities. Using a direct detection system for nitric oxide radical (NO·) by electron spin resonance (ESR) spectrometry in an in vitro ·NO-generating system, we examined the quenching effects of pergolide on the amount of NO· generated. Pergolide dose-dependently scavenged NO·. In the competition assay, the IC₅₀ value for pergolide was estimated to be about 30 μM. Pergolide also dose-dependently attenuated the hydroxyl radical (·OH) signal in an in vitro FeSO₄–H₂O₂ ESR system with an approximate IC₅₀ value of 300 μM. Furthermore, this agent significantly inhibited phospholipid peroxidation of rat brain homogenates in in vitro experiments and after repeated administration (0.5 mg/kg/24 h, i.p. for 7 days). Our findings suggest a neuroprotective role for pergolide on dopaminergic neurons due to its free radical scavenging and antioxidant properties.     

Quantitative determination of pentane in exhaled air correlates with colonic inflammation in the rat colitis model

Oxygen radicals play a key role in inflammation and inflammatory tissue damage. Quantitative determination of pentane, a hydrocarbon generated by membrane lipid peroxidation initiated by oxygen radicals, in expired air has been used as a noninvasive determinant or index of inflammation in various conditions. Herein we report the first examination of the relationship between exhaled pentane and colonic inflammation in a rodent model of colitis. Colitis was induced in rats (n=33) using the trinitrobenzene-sulfonic acid (TNB) model of colitis. Exhaled air was collected in a closed chamber on randomly selected animals on days 1, 2, 4, 7, 11, 13, 15, 20, and 25 post-TNB treatment, and pentane was assayed by means of gas chromatography. Gross and microscopic evidence of inflammation was compared with exhaled pentane levels. Pentane levels varied from 0.0 to 14.6 nmol/l of air and were significantly increased in TNB-treated rats compared with control rats only on days 7 to 15 after treatment (P<0.05). Gross inspection showed severe colonie inflammation through the first week (mean score =4.7 out of a possible 5), persistent inflammation on days 7 to 15 (3.2), and healing and fibrosis from the end of week two until day 25 (1.9 to 0). Histologic evaluation confirmed a progression of inflammation from acute ulceration to chronic inflammation to fibrosis and scarring. We have demonstrated that pentane exhalation is increased after the induction of colonie inflammation, with a seven-day lag time, and returns rapidly to normal as acute inflammation resolves. This suggests that pentane exhalation can be used as a noninvasive measure of colonic inflammation in rodent models of colitis and perhaps clinically in humans.